US20130343906A1

US20130343906A1 - Starter system for an engine

Info

Publication number: US20130343906A1
Application number: US13/913,326
Authority: US
Inventors: Scott A. Funke; Robert Koenen; David W. Procknow; Jason A. Hansen; Stephen J. Lavender; Jason D. Elvers; Ramidu Mirissage; James Nommensen
Original assignee: Briggs and Stratton Corp
Current assignee: Briggs and Stratton Corp
Priority date: 2011-11-04
Filing date: 2013-06-07
Publication date: 2013-12-26
Also published as: US8857138B2; US9759175B2; US20150053164A1; US20130111865A1; US20160146174A1; US9267482B2

Abstract

A pressure washer includes an engine, a water pump driven by the engine, a starter motor coupled to the engine to start the engine, an energy storage device electrically coupled to the starter motor, a spray device including an activation device for starting and stopping a flow of water from the spray device, a pressure sensor, and a flow sensor. The water pump has a low pressure side and a high pressure side. The high pressure side provides pressurized water. The pressure sensor is located at the low pressure side and is configured to indicate a water pressure relative to a threshold pressure. The flow sensor is located at the low pressure side and is configured to indicate a water flow relative to a threshold flow. With the engine off, the starter motor starts the engine when the pressure sensor indicates the water pressure is above the threshold pressure and the flow sensor indicates the water flow is above the threshold flow.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 61/657,607, filed Jun. 8, 2012, which is incorporated herein by reference in its entirety. This application is a continuation-in-part of International Application No. PCT/US2013/035623, filed Apr. 8, 2013, which claims the benefit of U.S. Provisional Application No. 61/625,437, filed Apr. 17, 2012, and the benefit of U.S. application Ser. No. 13/692,739, filed Dec. 3, 2012, which is a continuation-in-part of U.S. application Ser. No. 13/289,613, filed Nov. 4, 2011, all of which are incorporated herein by reference in their entireties.

BACKGROUND

The present invention generally relates to internal combustion engines and outdoor power equipment powered by such engines, such as lawn mowers, snow throwers, portable generators, etc. More specifically, the present invention relates to a starter system and energy storage system for an engine.
Outdoor power equipment may use an internal combustion engine to drive a tool of the equipment, such as a rotary blade of a lawn mower or an axial cam pump of a pressure washer. Typically the outdoor power equipment includes a brake mechanism that selectively prevents or stops rotation of the tool. The brake may stop a flywheel of the engine, correspondingly stopping the crankshaft and rotating tool coupled to the power takeoff of the crankshaft.
Starting the braked outdoor power equipment may be cumbersome, requiring release of the brake followed by activation of the engine. For lawn mowers and other types of outdoor power equipment, release of the brake may include rotating a bail to draw an inner-wire of a Bowden cable that lifts the brake mechanism. Then, activation of the engine typically further includes manually pulling a recoil starter rope or activating an electric starter for the engine. A need exists for a less-cumbersome and faster process to start the outdoor power equipment.
Furthermore, the outdoor power equipment may include the engine mounted to a frame or a base plate. If an electric starter is included, the starter motor is typically connected to an interface on the handle of the outdoor power equipment so that the operator may activate the starter motor while standing in an operational position, such as behind the handle. During assembly of the outdoor power, a power source, control circuitry, and wiring associated with the starter motor are coupled to the handle, the frame, and the engine, the attachment of which may be a time-consuming and labor-intensive process. A need exists for an engine having a starter motor that facilitates efficient assembly of the outdoor power equipment.

SUMMARY

One embodiment of the invention relates to a pressure washer including an engine, a water pump driven by the engine, a starter motor coupled to the engine to start the engine, an energy storage device electrically coupled to the starter motor, a spray device including an activation device for starting and stopping a flow of water from the spray device, a pressure sensor, and a flow sensor. The water pump has a low pressure side and a high pressure side. The high pressure side provides pressurized water. The pressure sensor is located at the low pressure side and is configured to indicate a water pressure relative to a threshold pressure. The flow sensor is located at the low pressure side and is configured to indicate a water flow relative to a threshold flow. With the engine off, the starter motor starts the engine when the pressure sensor indicates the water pressure is above the threshold pressure and the flow sensor indicates the water flow is above the threshold flow.
Another embodiment of the invention relates to a pressure washer including an engine, a water pump driven by the engine and providing pressurized water, a starter motor coupled to the engine to start the engine, an energy storage device electrically coupled to the starter motor, a spray device including an activation device for starting and stopping a flow of water from the spray device, a pressure sensor configured to indicate a water pressure relative to a threshold pressure, a flow sensor configured to indicate a water flow relative to a threshold flow, and a controller configured to control the operation of the engine. With the engine off, the controller activates the starter motor to start the engine when the pressure sensor indicates the water pressure is above the threshold pressure and the flow sensor indicates the water flow is above the threshold flow.
Another embodiment of the invention relates to a pressure washer including an engine, a water pump driven by the engine, the water pump providing pressurized water, a starter motor coupled to the engine to start the engine, an energy storage device electrically coupled to the starter motor, a spray device including an activation device for starting and stopping a flow of water from the spray device, a sensor configured to indicate a water flow or a water pressure relative to a threshold, and non-programmable circuitry configured to control the operation of the engine. The non-programmable circuitry includes a starter motor activation circuit configured to activate the starter motor to start the engine when the sensor indicates the water flow above the threshold or the water pressure above the threshold.
Another embodiment of the invention relates to method of controlling an engine of a pressure washer, where, with the engine off, a starter motor is turned on to start the engine in response to a detected water pressure above a threshold pressure and a detected water flow above a threshold flow. In a further embodiment, the method also includes, with the engine on, implementing an off delay timer for tracking, up to a predetermined amount of time, a time for which the detected water flow is below the threshold flow, and turning the engine off when the predetermined amount of time is met. In a further embodiment, the method also includes reducing an engine speed while the off delay timer is tracking the time. In a further embodiment, the method also includes determining if the starter motor has successfully started the engine, and if the engine is successfully started, turning off the starter motor, and if the engine is not successfully started, implementing a starter motor cranking timer, for tracking, up to a predetermined amount of time, a time for which the engine is not successfully started and turning off the starter motor when the predetermined amount of time is met.
Alternative exemplary embodiments relate to other features and combinations of features as may be generally recited in the claims.

BRIEF DESCRIPTION OF THE FIGURES

The disclosure will become more fully understood from the following detailed description, taken in conjunction with the accompanying figures, in which:

FIG. 1 is a perspective view of a lawn mower according to an exemplary embodiment of the invention.

FIG. 2 is a perspective view of a handle for outdoor power equipment according to an exemplary embodiment of the invention.

FIG. 3 is a perspective view of a handle for outdoor power equipment according to another exemplary embodiment of the invention.

FIG. 4 is a schematic diagram of a starter system for an engine according to an exemplary embodiment of the invention.

FIG. 5 is a perspective view of components of a starter system for outdoor power equipment according to an exemplary embodiment of the invention.

FIG. 6 is a perspective view of an engine assembly according to an exemplary embodiment of the invention.

FIG. 7 is a perspective view of a battery charging station according to an exemplary embodiment of the invention

FIG. 8 is a perspective view of a battery being coupled to an engine according to an exemplary embodiment of the invention.

FIG. 9 is a perspective view of a starter for the engine assembly of FIG. 6 according to an exemplary embodiment of the invention.

FIG. 10 is a circuit diagram of a controller for a starter of an engine according to an exemplary embodiment of the invention.

FIG. 11 is a circuit diagram of a controller for a starter of an engine according to another exemplary embodiment of the invention.

FIG. 12 is a perspective view of a pressure washer according to an exemplary embodiment of the invention.

FIG. 13 is a circuit diagram for a starter system of an engine according to another exemplary embodiment of the invention.

FIG. 13A is a circuit diagram for a starter system of an engine according to another exemplary embodiment of the invention.

FIG. 14 a schematic diagram of the pressure washer of FIG. 12.

FIG. 15 is a flowchart of a method for controlling the engine of the pressure washer of FIG. 12.

FIG. 16 is a schematic diagram of outdoor power equipment according to an exemplary embodiment of the invention.

FIG. 17 is a front view of a control module of the outdoor power equipment of FIG. 16.

DETAILED DESCRIPTION

Before turning to the figures, which illustrate the exemplary embodiments in detail, it should be understood that the present application is not limited to the details or methodology set forth in the description or illustrated in the figures. It should also be understood that the terminology is for the purpose of description only and should not be regarded as limiting.
Referring to FIG. 1, outdoor power equipment, in the form of a lawn mower 110, includes an internal combustion engine 112 coupled to a rotary tool, such as the blade in a deck 114 of the lawn mower 110, an auger, a saw, tines, a drill, a pump, or other rotary tools. In some embodiments, the lawn mower 110 further includes wheels 116 and a rearward extending handle 118 designed to be pushed by an operator walking behind the lawn mower 110. In other contemplated embodiments, the outdoor power equipment may be in the form of a rotary tiller, a pressure washer, a snow thrower, a lawn tractor or riding mower, an edger, a portable generator, or other equipment, with a corresponding powered tool, such as tines, a pump, an auger and impeller, an alternator, a drive train, or other tools.
Still referring to FIG. 1, the lawn mower 110 includes a starter system. According to an exemplary embodiment, the starter system includes an electric motor 120 that is selectively coupled to the engine 112 such that the electric motor 120 is configured to rotate the crankshaft of the engine 112 to start the engine 112, and is then configured to disengage once the engine 112 is running. In some embodiments, the motor 120 is fastened to the engine 112, such as being mounted on top of or to a side of the engine 112. Gearing (e.g., gear reduction, transmission) may extend between the motor 120 and the crankshaft of the engine 112, or the motor 120 may be connected directly to the crankshaft of the engine 112.
According to an exemplary embodiment, an operator may engage the starter system via the handle 118 of the lawn mower 110. In some embodiments, the handle 118 includes a lever 122, button, toggle, or other interface that the operator may use to command the starter system to start the engine 112. In some embodiments, the command is relayed from the handle 118 via a linkage 124, such as an electric wire transmitting an electrical signal, a Bowden cable communicating a mechanical signal, or another type of linkage. In contemplated embodiments, a transmitter and start button are coupled to the handle (e.g., clipped on, integrally mounted with), and the starter system includes an integrated receiver configured to receive commands wirelessly provided by the transmitter to start the engine. According to an exemplary embodiment, the command from the operator is received directly or indirectly by the motor 120, and the motor 120 rotates the crankshaft to start the engine 112.
In some embodiments, the starter system is integrated with a bail 126 of the lawn mower 110. A brake mechanism (e.g., friction brake, ignition interrupt switch or circuit, etc.) may be holding the blade or other tool, locking the crankshaft of the engine 112, or otherwise preventing operation of the power equipment. When the operator actuates the bail 126 to release the brake mechanism from rotating members (e.g., blade, crankshaft, power takeoff, flywheel) of the lawn mower 110, the action simultaneously actuates the motor 120 to start the engine 112. As such, releasing of the brake mechanism synergistically also starts the engine 112, easing operation of the lawn mower 110 or other outdoor power equipment by reducing the steps necessary for activation.
In some embodiments, the lawn mower 110 includes an interlock 128 (e.g., lock-out device, signal interrupt) to prevent release of the brake and engagement of the motor 120. According to an exemplary embodiment, the operator must release the interlock 128 before the bail 126 can be operated to engage the motor 120 to start the engine 112. Different types of mechanical and electrical interlocks may be used in varying contemplated embodiments to prevent inadvertent release of the brake and starting of the engine, such as when a user moves the power equipment into or out of a garage or storage shed by grabbing the handle, or if the bail is unintentionally bumped. Furthermore, engagement of the interlock 128, in some embodiments, is also configured to prevent inadvertent release of the brake when the handle 118 is being folded over the deck 114 to put the lawn mower 110 in a storage configuration.
In some embodiments, the interlock 128 may prevent a signal from being sent via the linkage 124 to engage the motor 120 and release the brake. The interlock 128 may physically disconnect the linkage 124 from the bail 126, such as by removing a linking pin that joins the bail 126 to the linkage 124, removing a clamp that holds the linkage 124 to the bail 126, or otherwise physically separating the bail 126 and linkage 124. Release of the interlock 128 then physically or electrically connects the bail 126 (or other brake release) to the controller 132 (e.g., control system, control circuit, computerized controller) such that operation of the bail 126 is communicated to the controller 132 to simultaneously start the engine 112.
In other embodiments, the interlock 128 physically prevents (e.g., blocks, holds, jams) rotation of the bail 126 when the interlock 128 is engaged. In some such embodiments, a cam may be rotated into or out of the path of the bail 126, optionally preventing rotation of the bail 126. In other such embodiments, a clamp of the interlock 128 may bind the bail 126 to the handle 118, preventing rotation of the bail 126 until released. In still other such embodiments, a sleeve or latch may slide over the bail 126, holding the bail at a fixed angle until released. The mechanical interlock described in this paragraph may be used in an embodiment where no electrical wiring harness on the handle 118 is required to support the starting of the electric motor 120 and engine 112.
In contemplated embodiments, an electrical signal may indicate to the controller 132 that the interlock 128 has been released, such as a signal communicated via the linkage 124, via radio frequency communication, hardwired, or otherwise. The signal is provided in addition to a separate signal associated with movement of the bail 126. Without the signal indicating release of the interlock, the signal associated with movement of the bail will not be sufficient to instruct the controller to start the engine. The electrical signal may be associated with a pass code, a key, a scanned finger print, or other access-limiting device.
According to an exemplary embodiment, the lever 122 (e.g., interface, release mechanism, trigger) may serve to release the interlock 128, allowing operation of the bail 126 to release the brake and to start the motor 120. In some embodiments, pulling of the lever 122 may move a physical obstacle out of the rotational path of the bail 126. In other embodiments, pulling of the lever 122 may mechanically or electrically connect the bail 126 and the linkage 124. Other mechanisms, such as buttons, switches, toggles, dials, etc., may serve as release mechanisms to release the interlock 128. In some embodiments, conventional mechanical rotational interlocks or electrical switches (e.g., signal disconnects) are used as the interlock.
In general, integration of the starter system with a handle of outdoor power equipment allows the operator to start the engine from the rear of the outdoor power equipment, such as several feet from the powered tool of the outdoor power equipment (e.g., snow thrower auger, lawn mower blades). Further, the integration supports an electric starting system for a walk behind mower that can be engaged by a user without actuation of a key or push-button. In other embodiments, the starter system may include a start button or other interface to engage the starter system that is located on the engine or elsewhere. For example, in contemplated embodiments, such an interface may include a smart phone application or remote control that wirelessly provides a start command or authorization code to a receiver coupled to the outdoor power equipment.
According to an exemplary embodiment, the starter system further includes an energy storage device 130 (e.g., electrical storage device) and a controller 132. The energy storage device 130 may include one or more batteries, capacitors, or other devices. When the operator engages the starter system, the linkage 124 communicates the command to start the engine directly or indirectly to the controller 132, which electrically connects the energy storage device 130 to power the motor 120. In some embodiments, the controller 132 is coupled to a governor of the engine 112 (see, e.g., speed sensor 420 as shown in FIG. 4), and disengages the motor 120 (e.g., cuts power to the motor 120, high-side switching of the battery power source, low-side switching of the ground side of the circuit) when the engine 112 is running at a sufficient speed.
In some embodiments, the motor 120, the energy storage device 130, and the controller 132 are fastened directly to the engine 112, which may be configured for efficient assembly of outdoor power equipment using the engine 112. As such, the starter system in some embodiments may come fully assembled with the engine 112 and ready for connection to a linkage configured to provide a signal from the handle (e.g., linkage 124). In some embodiments, an interface (e.g., start button, toggle, switch) for starting the engine is positioned on the engine itself, and no additional connections are necessary—the manufacturer need only attach the engine to the deck or corresponding feature and attach the tool to the power takeoff of the engine. In any such case, considerable time and effort may be saved during the manufacturing process and a potential source of manufacturing difficulty may be removed (i.e., that associated with the fastening and electrical connection of the components of the starter system during assembly of the outdoor power equipment). In still other embodiments, some or all of the starter assembly may be fastened to the deck of a lawn mower or corresponding feature of other power equipment.
Referring to FIGS. 2-3, handles 210, 310 for outdoor power equipment, such as a lawn mower, rotary tiller, snow thrower, etc., each include a bail 212, 312 and an interlock 214, 314 with a release button 216, 316. In contemplate embodiments, the release button 216, 316 may release the bail 212, 312 from being interlocked by allowing the bail 212, 312 to move, or by coupling the bail 212, 312 and linkage 124. In FIG. 2, the release button 216 is to the side of the bail 212, while in FIG. 3, the release button 316 for the interlock 314 is on top of the bail 312. The release button 216 of FIG. 2 may disengage a member from blocking movement of the bail, while the release button 316 may connect the bail 312 and linkage 124. In other contemplated embodiments, release buttons or other release mechanisms may be positioned elsewhere on the handle, the engine, or on another component of the outdoor power equipment.
Still referring to FIGS. 2-3, in other contemplated embodiments, the buttons 216, 316 may be used to provide a signal directly or indirectly to a motor to start an engine, without regard to the bail 212, 312. However, integrating the buttons 216, 316 with the bail 212, 312 allows for a two-step process to start the engine (i.e., release interlock and operate bail), while synergistically using the operation of the bail 212, 312 to both release the brake as well as to engage the starter. In still other embodiments, other forms of interlocks and release mechanisms for the interlocks may be used, such as a biased lever (see lever 122 of interlock 128 as shown in FIG. 1), latch, thumb-print reader, etc.
In some embodiments, a three-step process is used to engage the power equipment, such as first disabling or releasing an interlock; second presenting a key, a code, or other device to release an access-control mechanism (e.g., lock out, lock); and third pulling the bail. In alternate embodiments, the key hole or interface for the access-control mechanism may be positioned on the handle or on the engine.
Referring to FIG. 4, outdoor power equipment 410 (shown schematically) includes an engine 412 and a powered tool 414 (e.g., rotary blade) driven by the engine 412. In some embodiments, a motor 416 is coupled to the engine 412, and the powered tool 414 is coupled to a power takeoff 418 of the engine 412. A speed sensor 420 (e.g., governor) may be coupled to the engine 412 to regulate the speed of the engine 412. Also, a brake 422 may be coupled to a rotary member of the outdoor power equipment 410, such as the flywheel of the engine, the power takeoff 418 of the engine, etc., to stop the engine as well as the associated powered tool.
In some embodiments, the outdoor power equipment 410 includes a handle 424 having a release mechanism 426, where the release mechanism 426 is configured to allow a user to release the brake 422 from the handle 424. The release mechanism 426 may allow a user to release the brake 422 by engaging the bail (or other element) with a linkage connected to the brake 422, or by disengaging an element blocking movement of the bail. The handle 424 may be coupled to the engine 412 and tool 414 directly, or via an intermediary member (e.g., deck 114 as shown in FIG. 1). The engine 412 may further include a battery 428 for powering the motor 416 and a control system 430 for operating the motor 416.
According to an exemplary embodiment, the control system 430 is configured to receive inputs associated with the release mechanism 426. In some embodiments, when the release mechanism 426 is actuated to release the brake 422, the release mechanism 426 triggers a switch 432, which provides to the control system 430 a signal that is indicative of the release of the brake 422. The signal may be provided via a mechanical linkage, wirelessly, a hardwired electrical connection, or otherwise. In some embodiments, the control system 430 then actuates the motor 416 to start the engine 412 or uses the information in control logic configured to start the engine as a function of the status of the brake and other factors. As such, operation of the release mechanism 426 may simultaneously provide a start signal to the control system 430 as well as release the brake 422. No additional operations to start the engine 412 may be required.
According to an exemplary embodiment, the control system 430 is configured to receive additional inputs from the speed sensor 420 or another component of the engine 412 (e.g., ignition circuit). The speed sensor 420 or other component provides the control system 430 with information associated with the speed of the engine 412. When the engine 412 is running at a sufficient speed, the control system 430 then disengages the motor 416 (e.g., turns off, disconnects, cuts power to, etc.).
In contemplated embodiments, the control system 430 associated with the start system may receive additional or different inputs used to control starting of the engine, such input from a sensor configured to indicate whether the outdoor power equipment has moved recently. Movement of an axle or wheels of such outdoor power equipment may trigger a sensor that provides a signal to the control system. The signal, in combination with an electric timer providing time-related context for the movement, may serve as an additional indicator that the operator intends to activate the engine. In contemplated embodiments, the control system 430 includes a timer and is configured to deactivate the motor if the engine has not started within a predetermined amount of time. In some contemplated embodiments, the control system 430 includes a temperature sensor and is configured to prime the engine with an automated primer pump or adjust the choke or throttle plate if ambient temperature is above or below a predetermined temperature, if a portion of the engine is above or below a predetermined temperature, or if the difference between ambient and engine temperature is above or below a predetermined amount. In contemplated embodiments, the control system 430 may also provide a signal output to the operator, such as a visible indicator on a display coupled to the handle or engine, or an audible alert. In some such embodiments, the signal output may include as an error message, a low-fuel message, a replace-oil message, or another such message.
Referring to FIG. 5, components of a system 510 include a brake cable 512 (e.g., Bowden cable) and a brake pad 514 for an associated engine of outdoor power equipment. According to an exemplary embodiment, the brake cable 512 is configured to be coupled to the bail of a handle of outdoor power equipment (see, e.g., bails 126, 212, and 312 as shown in FIGS. 1-3). When an operator activates the bail, the brake cable 512 moves a pivot 516 coupled to the brake pad 514. The brake pad 514 then releases, allowing the engine associated with the system 510 to drive a powered tool of the outdoor power equipment.
According to an exemplary embodiment, the engine associated with the system 510 further includes a starter system including a switch 518, an electronic control 520, a battery 522, and an electric starter motor 524. When the operator activates the bail to lift the brake pad 514, the pivot 516 simultaneously activates the switch 518. The switch 518 then provides a signal to the electronic control 520 that the brake pad 514 has been lifted and that the electronic control 520 may start the engine associated with the system 510 with the electric starter 524. The electronic control 520 then connects the electric starter 524 to the battery 522. The switch 518 may be a switch already associated with the brake, but used to provide signals to both an actuator of the brake and the starter system (e.g., ignition ground), or the switch 518 may be an additional switch solely used for the starter system.
Still referring to FIG. 5, the electronic control 520 includes hard-wired circuitry and is configured to receive additional inputs from the engine associated with the system 510. In some embodiments, the additional inputs include an indication of the speed of the engine associated with the system 510 from a governor or other component of the engine (e.g., electrical pulses from the ignition system). The additional inputs may include a current state of the engine associated with the system 510, such as whether the engine associated with the system 510 is running, etc. The starter system is also coupled to a ground 526.
Referring to FIGS. 6-9, an engine 610 includes an exhaust 612, a fuel tank 614, an engine cover 616, an air intake 618 for combustion processes, an air intake 620 for cooling the engine, and a starter system having an energy storage device, such as a battery 622 (e.g., lithium-ion, lead-acid, etc.), a capacitor, multiple batteries or capacitors, or another energy storage device. Applicants note that the engine 610 of FIGS. 6-9 mirrors the engine 112 of FIG. 1, and both are single-cylinder, four-stroke cycle, vertically-shafted, small engines. Other engine types and designs may be used, such as engines that are horizontally-shafted, two- or more cylindered, diesel powered, cold-weather structured, etc.
Although shown as proximate to the fuel tank 614 and exhaust 612 in FIGS. 6 and 8-9, the energy storage device may be positioned elsewhere on the exterior and/or in an internal port of the engine 610. In some embodiments, where the energy storage device is sensitive to high temperature, it may be preferred to position the energy storage device away from the exhaust 612, which may become hot during operation of the engine 610.
According to an exemplary embodiment, the energy storage device 622 is configured to power a starter motor (see, e.g., motor 120 as shown in FIG. 1) integrated with the engine 610. In some embodiments, the energy storage device may be further configured to power other systems of the engine 610, such as an engine control unit (ECU) having control circuitry coupled to sensors or detectors integrated with the engine (e.g., brake release, fuel-level detector, ignition-fouling detector, governor, etc.).
According to an exemplary embodiment, the energy storage device is the battery 622, which is rechargeable. As shown in FIG. 7, the battery 622 may be charged at a charging station 624 or may include a charging port integrated with the battery (e.g., battery pack with charging port to receive a connection from a wire coupled to an outlet or the charging station). The battery 622, in other embodiments, may alternatively plug directly into a wall outlet, or the charging station may be wall mounted or plug directly into a wall outlet.
In some embodiments, the energy storage device is or includes a bank of capacitors, where the capacitors are configured to charge and release electrical energy in a relatively short (e.g., less than 10 seconds), high-powered output. In some such embodiments, some of the capacitors of the bank are coupled with one another in groups (e.g., series or parallel), and the groups are configured to output sequentially in time with respect to one another. Accordingly, the capacitors are specifically configured to be able to power the motor to start the engine 610 without much additional energy storage capacity so as to be relatively compact in size and inexpensive. Use of capacitors may also allow for faster charging when compared to batteries, such as faster charging on the charging station 624 (FIG. 7).
In contemplated embodiments, the starter motor is configured to draw power from the engine 610, such as during periods of lesser loads on the engine. The starter motor is then driven by the engine 610 to provide an electric output. The electric output may then be routed by the ECU or otherwise to charge the energy storage device. Such a system may be particularly useful for an engine driving an alternator of a portable generator, where the alternator may temporarily be powered by the energy storage device to start the engine and then, once the engine has started, the alternator may be used to recharge the energy storage device.
Referring to FIG. 8, the battery is configured to be inserted (e.g., dropped, lowered, placed) into a receiving port 626 integrated with the engine. Integrating the receiving port with the engine reduces the assembly burdens for manufacturing outdoor power equipment, as disclosed above. However in contemplated embodiments, the receiving port may not be integrated with the engine. For example, FIG. 7 shows a charging station 624 or charging port, which may be similar to such a port on a deck of the engine.
In some embodiments, the battery 622 has a cross section forming an isosceles trapezoid, triangle, diamond, or other wedge shape, or shape having a narrower lower portion 628 relative to an upper portion 630 in contact with the receiving port 626. The receiving port 626 is contoured (e.g., V-shaped, U-shaped, etc.) to receive the battery 622, which may be guided into position by interfacing with the contours of the receiving port 626 and gravity.
In some embodiments, the battery 622 includes slots or grips 632 for lifting and holding the battery 622. A locking mechanism, such as a hook or latch may snap into place when the battery 622 is inserted into the receiving port 626 and hold the battery 622 in the receiving port 626. Pinching the grips 632 together may release the locking mechanism to allow removal of the battery 622 from the receiving port 626.
According to an exemplary embodiment, the starter system further includes a switch 636 (e.g., toggle, lever, key) that is integrated with the battery 622, the receiving port 626, or elsewhere on the engine 610. As shown in FIGS. 8-9, the switch 636 may rotate from an off position (FIG. 8), where the battery 622 is not electrically connected to components of the engine 610 (e.g., starter motor, ECU), to an on position (FIG. 9), where the battery 622 is electrically connected to the components. In other embodiments, rotation of the switch 636 also or alternatively engages the locking mechanism to hold the battery 622 in the receiving port 626. In various contemplated embodiments, the switch 636 may be configured to interrupt electrical connectivity of the battery, the control circuit, or both.
According to an exemplary embodiment, the starter system includes an interface, shown as a button 634 on the receiving port 626. In other exemplary embodiments, the starter system may include another type of interface, such as a toggle switch, a rocker switch, a capacitive switch, etc. The interface, such as the button 634, may be located on the engine 610 and face outward and is accessible when the battery 622 is seated in the receiving port 626. In some embodiments, the interface allows the operator to start the engine via the starter system. In other embodiments, the interface may be used to initiate charging of the battery or another function.
Referring now to FIGS. 12 and 14, a pressure washer 710 includes a frame 711 supporting an engine (e.g., the engine 610 shown in FIGS. 6-9), and a water pump 713 (e.g., positive displacement pump, piston water pump, axial cam pump) configured to be connected to a spray gun 714 (e.g., spray gun, spray wand, brush, other spray device, etc.) with a delivery hose or conduit 715 (e.g., a high-pressure hose). In some embodiments, the engine 610 is fastened to the top of a base plate of the frame 711 and the water pump 713 is mounted below the base plate and connected to the engine 610 via a hole through the base plate. In other embodiments, the water pump 713 is directly coupled to and supported by the engine 610. The water pump 713 is coupled (e.g., directly coupled, indirectly coupled by a transmission, belts, gears, or other drive system) to the engine 610 to be driven by the engine 610. In some embodiments, the pressure washer 710 is portable and includes wheels 717 and a handle 718. In other embodiments, the pressure washer 710 may be stationary. In other embodiments, the pressure washer 710 is mounted to a trailer or other vehicle. The water pump 713 includes a pump inlet 719 and a pump outlet 721. The pump inlet 721 is configured to be coupled to a supply conduit or hose 723, which is in turn connected to a fluid supply 725 (e.g., a spigot connected to a municipal water supply or well). In some embodiments, the pump inlet 719 includes a low-pressure, garden-hose style fitting for coupling a garden hose to the pump inlet 719. The pump outlet 721 includes a high-pressure fitting (e.g., an M22 fitting) for coupling the pump outlet 721 to the delivery hose 715 or other device including an appropriate high pressure fitting. As shown in FIGS. 12 and 14, pressure washer 710 uses a vertical shaft engine. According to an alternative embodiment, the engine may be a horizontal shaft engine.
In some embodiments, an operator may press the button 634 to start the engine 610. In some embodiments, the motor 120 is a motor/generator that may provide power to charge the battery 622 of the starter system when operating in the generator mode. According to an exemplary embodiment shown in FIG. 12, the battery 622 is coupled to the engine 610. According to another exemplary embodiment, the battery 622 is coupled to the frame 711 or other location on the pressure washer 710 other than the engine 610.
As pressure washer 710 does not have a bail similar to bails 126, 212, 312 shown in FIGS. 1-3, the electrical switch associated with the button 634 may be more complex than that used in lawnmower applications utilizing a bail. That is, in some of the lawnmower configurations described herein, a single-pole-single-throw switch is used to send power (e.g., 12 volts) to power up and start the engine when the user pulls the bail, and then removes the power (e.g., 12 volts) and shorts the ignition to ground when the user releases the bail, thus stopping the engine. However, on non-mower applications that do not use a bail, either a double-pole-double-throw switch or other solid state electronics may be used to ground the ignition on one pole when in the OFF position, and sends power (e.g., 12 volts) to the second pole when in the ON position. In this way, one position removes the power (e.g., 12 volts) and shorts the ignition (OFF), while the other position un-shorts the ignition and applies the power (e.g., 12 volts) (ON).
As an alternative or in addition to the button 634 or other interface of the starter systems described above, and in accordance with another exemplary embodiment, engine 610 of pressure washer 710 may be started via actuation of a trigger 712 on the spray gun 714 shown in FIG. 12. Such trigger-start control systems and other control systems described herein (e.g., the circuits shown in FIGS. 10-11, 13, and 13A and the method shown in FIG. 15) may be implemented as “non-programmable circuitry” that consists of analog or digital hard circuitry that does not utilize a microcontroller or software. It is believed that embodiments in which the controls are implemented as non-progammable circuitry including discrete components may be less expensive than embodiments implemented with microcontrollers or using software. Such non-programmable circuitry embodiments do not include a microcontroller.
An example circuitry schematic in accordance with the proposed embodiment is illustrated in FIG. 13. Block 734 shown in FIG. 13 represents the same starter system circuitry as is illustrated in FIG. 11. The present embodiment related to pressure washer 710 requires additional circuitry to function effectively. For instance, block 735 acts as a starter motor cranking limiter, which limits the amount of time the starter motor 120 can crank without the engine 610 starting. Block 736 represents a flow sensor and/or a pressure sensor, which senses water flow or pressure, respectively, through the system, as will be discussed further herein. Block 737 represents an ON time delay circuit, which detects the amount of time that a user has actuated trigger 712 and prevents starting of the engine 610 if a predetermined time period has not elapsed (e.g., during incidental user contact with trigger 712). Block 743, on the other hand, represents an OFF time delay circuit, which allows the engine to continue running for a predetermined period of time after the user has released trigger 712. Following the expiration of this timer, the engine 610 is turned off. Block 743 may contain a connection to a device (e.g., a potentiometer, dial, keypad, touchscreen, other user input device) which allows for user customization of the OFF time delay. The user-set OFF time delay may be infinitely variable across a range of values or variable in preset units (e.g., 1 second, 5 seconds, 10 seconds, 15, seconds, 30 seconds, 1 minute). Block 739 represents a manual stop override input (e.g., via an enable key insert, button, keyswitch, toggle switch, other user input device) for the OFF time delay, which allows a user to deactivate the OFF time delay and immediately disable the engine by grounding the ignition. Finally, block 741 represents circuitry that detects when the starter motor is turning, but there is no indication from the engine (e.g., the flywheel or ignition) that the engine is turning. This condition may indicate that the pinion gear has improperly disengaged from the engine's flywheel gear (i.e., a pinion gear “kickout”) or that something is preventing the engine from turning. After detecting this condition, the circuitry may be configured to either automatically reinitialize the starting process or stop the starting process until the user reinitializes the starting process. The overall operation of the starter system represented by the circuitry shown in FIG. 13 will be discussed below. Although FIG. 13 illustrates a circuit for use with a specific type of ignition coil, the circuit may be modified to accept universal ignition coils or any other appropriate type of ignition coil. Additionally, the electric starter system shown in FIG. 13 or any of the other electric starter systems described herein may include provisions allowing for the use of a manual starter. The manual starter (e.g., a recoil starter, a rope-pull starter, etc.) allows the user to manually start the engine in the event of insufficient battery voltage to power the starter motor or if a removable battery cannot be located for use with the outdoor power equipment.
FIG. 13A illustrates an alternative version of non-programmable circuitry for implementing a trigger-start operation of a pressure washer. The non-programmable circuitry include multiple discrete components that implement the various operations described in more detail below and elsewhere in the application. A starter motor activation circuit (block 900) allows for trigger starting a pressure washer based on inputs from a flow sensor and a pressure sensor (block 905). Alternatively, a flow sensor is used alone or a pressure sensor is used alone as explained elsewhere. The flow sensor and the pressure sensor provide signals that indicate when the detected flow and pressure, respectively, are above a threshold. The flow sensor and the pressure sensor may be arranged in series or in parallel. An on delay timer circuit (block 910) requires that the flow sensor detects flow above the threshold and the pressure sensor detects pressure above the threshold for a predetermined amount of time before the starter motor activation circuit provides a signal to crank (e.g., start, turn on, etc.) the starter motor. Crank limiting timer circuit (block 915) allows the starter to crank for a predetermined amount of time (e.g., 10 seconds). When the timer expires, cranking is stopped (e.g., the starter motor is stopped, turned off, etc.). Crank limiting timer reset circuit (block 920) resets the timer of the off time delay circuit (block 925) when the user stops the cranking operation (e.g., by releasing the trigger on the spray gun) while the timer of crank limiting reset circuit (block 920) is running. This helps to ensure that the timer of the crank limiting timer circuit (block 920) is able to run for the full amount of time each time the user initiates the process to crank the starter motor.
An off time delay circuit (block 925) stops the engine following the expiration of a predetermined amount of time. The timer begins to run when the detected flow drops below the threshold, stops when the detected flow rises above the threshold, and restarts when the detected flows drops below the threshold before the predetermined amount of time is met. In some embodiments, pressure sensing is used in addition to or in place of flow sensing, with the timer started, stopped, and reset in response to changes in detected pressure and/or detected pressure relative to one or more threshold pressures. Engine stop circuit (block 930) stops the engine by shorting the ignition. Engine stop circuit (block 930) may receive inputs to stop the engine from the off time delay circuit (block 925), a user interface (e.g., button, switch, etc., like the rocker switch associated with off timer bypass circuit 940), or from the starter motor lockout circuit (block 960). Off time reset circuit (block 935) resets the timer of the off time delay circuit (block 925) when the user releases the trigger while the starter motor is cranking, but the engine is not yet running. An off timer bypass circuit (block 940) allows the user to manually stop the engine without waiting for the timer of the off time delay circuit (block 925) to expire. The off timer bypass circuit (block 940) also resets the timer of the off time delay circuit (block 925) to allow the user to initialize a restart without having to wait for this timer to expire. In some embodiments, a rocker switch having three positions (i.e., trigger start, manual start, off) provides the input to the off timer bypass circuit 940.
Ignition speed sensing circuit (block 945) converts an output from any appropriate type of ignition coil to a signal usable as engine speed indication. The ignition speed sensing circuit (block 945) allows multiple types of ignition coils to be used with pressure washers or engines equipped with the circuitry of FIG. 13A without having to modify the circuitry to accommodate each type of ignition coil. Cranking may be stopped (i.e., the starter motor is turned off) when the engine reaches a threshold speed.
Power for the starting system is supplied by a rechargeable battery. In some embodiments, the battery is removable from the pressure washer or engine. The rechargeable battery can be recharged by a charging unit (block 950) or by trickle charging with excess or waste energy from the ignition coil (block 955). Starter motor lockout circuit (block 960) prevents the starter motor from cranking under three conditions. First, it prevents the starter motor from restarting until the engine has come to a stop (e.g., the flywheel has stopped spinning). Second, it prevents the starter motor from cranking when the charging unit is charging the battery (e.g., plugged in). Third, it shuts off the running engine when the charging unit is plugged in to charge the battery. This helps to prevent damage to the charging unit. An LED, light, or other indicator (block 965) is activated when the engine is running.
Referring to FIG. 14, which shows pressure washer 710 schematically, spray gun 714 is connected to the outlet 721 of the water pump 713 via hose 715 (i.e., fluidly coupled), wherein the inlet 719 of the water pump 713 is connected to a fluid supply 725 via another hose 723 (i.e., fluidly coupled). The spray gun 714 includes a trigger 712 that actuates a valve in the spray gun 714 to control the flow of fluid through the spray gun 714. Although illustrated as a lever, the trigger 712 encompasses all types of appropriate activation devices, including buttons, switches, knobs, dials, touch pads, touch screens, touch sensors, etc. In a first position of the trigger 712, the valve is open, and in a second position, the valve is closed. With the fluid supply 725 connected to the water pump 713, actuation of trigger 712 allows at least a small amount of water to flow through the spray gun 714 and the water pump 713, even when the engine 610 and the water pump 713 are not operating. A flow sensor 727 (e.g., flow sensor, flow switch, flow transducer, etc.) and a pressure sensor 729 (e.g., pressure sensor, pressure switch, pressure transducer, etc.) are used to sense the flow and pressure, respectively, within the fluid system. A manual starter 730 (e.g., a recoil starter, a pull-rope starter, etc.) allows the user to manually start the engine 610 if desired. In some embodiments, the manual starter 730 is omitted.
In some embodiments, the flow or pressure sensor comprises a sensor or transducer that generates a variable signal (e.g., resistance, current, voltage, etc.) in proportion to the sensed value of flow or pressure (e.g., an analog sensor). Such an analog sensor may be used to compare the detected flow or pressure to a threshold flow or pressure. In some embodiments, the flow or pressure sensor comprises a binary switch that turns on and off in response to a comparison of the detected flow or pressure to a predetermined threshold. When the trigger 712 is actuated, the flow sensor 727 detects a flow of fluid through the fluid system relative to a threshold flow (e.g., above a threshold flow, below a threshold flow, etc.) at the flow sensor location and the pressure sensor 729 detects a pressure of the fluid relative to a threshold pressure (e.g., above a threshold pressure, below a threshold pressure, etc) at the pressure sensor location. The flow sensor 727 and the pressure sensor 729 communicate with the starter system (e.g., control circuitry and starter motor) to start the engine 610 when the threshold flow and pressure are detected. Alternatively, rather than both flow and pressure being used as inputs to the starter system, flow alone (e.g., via one or more flow sensors) or pressure alone (e.g., via one or more pressure sensors) may be used as inputs to the starter system for initializing the starting process and/or the stopping process.
The fluid system includes the supply hose 723, the pump inlet 719, the water pump 713, the pump outlet 721, the delivery hose 715, and the spray gun 714. The flow sensor 727 and the pressure sensor 729 may be positioned at any appropriate location within the fluid system. In some embodiments, the flow sensor 727 (e.g., either self-contained or integrated within the water pump 713) may be placed between the fluid supply 725 and the pumping mechanism (i.e., the low pressure side) or between the pumping mechanism and the spray gun 714 (i.e., the high pressure side). In other embodiments, one or both of the flow sensor 727 and the pressure sensor is included in the spray gun 714. As illustrated in FIG. 14, the flow sensor 727 and the pressure sensor 729 are located on the low pressure side of the fluid system (e.g., at or near the pump inlet 719). In some embodiments, the flow sensor 727 and the pressure sensor 729 are located on the high pressure side of the fluid system. In other embodiments, one of the flow sensor 727 and the pressure sensor 729 is located on the low pressure side and the other is located on the high pressure side.
In some embodiments, once the pressure sensor 729 detects the threshold pressure and the flow sensor 727 detects the threshold flow, the engine 610 can be started using the same logic as the push-button starter system described in previous embodiments. For example, the starter system may be arranged so that the pressure sensor 729 checks for a pressure above a threshold pressure (e.g., 20 psi, 25 psi, 30 psi, 35 psi, 40 psi, or other expected pressure from the fluid supply) indicative of sufficient fluid being available to run the water pump 713 and then, after checking for the threshold pressure, starts the engine 610 in response to the flow sensor 727 detecting a fluid flow above the threshold flow (e.g., 0.1 gpm, 0.2 gpm, 0.3 gpm, 0.4 gpm, 0.5 gpm, or other expected flows from the fluid supply when the fluid is allowed to flow through the spray gun 714) indicative of fluid flow through the spray gun 714.
In some embodiments, the pressure sensor 729 is omitted and only flow sensing is used. In some of these embodiments, one or more flow sensors 727 detect fluid flow relative to a threshold flow at the flow sensor location. Alternatively, one or more analog flow sensors are used that provide a signal indicative of an actual flow value (e.g., in gpm), rather than detecting flow using a binary on/off-style flow switch. For example, in some embodiments, a single flow sensor 727 on the low pressure side of the fluid system is used to detect flow relative to a threshold flow so that the engine 610 is started when the detected flow is above the threshold and the engine 610 is stopped when the detected flow is below the threshold and/or at zero flow. In some embodiments, a start delay timer is included that requires the detected flow to be above the threshold for a predetermined amount of time (0.5 seconds, 1 second, 1.5 seconds, 2 seconds, etc.) before starting the engine 610. Alternatively, a single flow sensor 727 on the high pressure side could be used, but a flow sensor suitable for use at higher pressures would typically need to be more robust, and therefore more complex and/or expensive, than a flow sensor suitable for use at lower pressures. In some embodiments, the flow sensor 727 is omitted and only pressure sensing is used. If pressure sensing is used, two pressure sensors 729 may be used, one located at the pump inlet 719 and the other at the pump outlet 721. In some of these embodiments, one or more pressure sensors 729 detect fluid pressure relative to a threshold pressure. For example, in some embodiments, pressure sensor 729 is used to detect fluid pressure so that engine 610 is started when the detected pressure is below a first threshold pressure (i.e., in response to the drop in pressure caused when the valve in the spray gun 714 is opened) and stopped when the pressure sensor 729 detects a pressure above a second threshold pressure (i.e., in response to a pressure spike indicative of the valve in the spray gun 714 being closed). Such pressure sensing could occur on either the low pressure side or the high pressure side. Depending on the location of the pressure sensor 729, the pressure drop or spike to be sensed, may be relatively large, small, or tiny. For example, implementing this sensing on the low pressure side typically would require a sophisticated pressure sensor capable of detecting relatively small changes in pressure. Alternatively, a pressure differential sensor may be used to measure the pressure difference across the water pump 713 (e.g., between the pump inlet 719 and the pump outlet 721) and to provide inputs to the starter system to start and stop the engine 610 in response to the detected pressure differential.
Alternatively, a switch could be directly engaged by actuation of the trigger 712 to start the engine 610, wherein an electrical connection (e.g., wires) runs between the switch and the starter system (e.g., control circuitry and starter motor) for the engine 610 along or through the delivery hose 715. Alternatively, a switch could be directly engaged by actuation of the trigger 712 to start the engine 610, wherein wireless communication (e.g., radio frequency (RF), Infrared (IR), Bluetooth, or other form of wireless communication) is used between the switch and the starter system (e.g., control circuitry and starter motor) of the engine 610.
During connection of the fluid supply 725 to the water pump 713 and subsequent filling of the water pump 713, the flow sensor 727 and/or the pressure sensor 729 may sense a short-duration flow of water or a pressure change before the trigger 712 is actuated. Therefore, in some embodiments, the engine 610 does not start immediately upon sensing flow or pressure change. Instead, a timed delay start (e.g., 0.5-3 seconds) could be provided by the starter system circuitry described above. For example, the timed delay start could be established via a timer, resistor-capacitor circuit (RC circuit), or equivalent. The timed delay start would eliminate the possibility of unintentional engine starting. In some embodiments, the duration of the timed delay start is adjustable by the user (e.g., via a user input device).
Similarly, it may not be desirable for engine 610 to stop (i.e., turn off) immediately upon user release of trigger 712. Instead, a timed delay stop (e.g., 1-2 minutes) could be provided by the starter system circuitry described above. For example, the timed delay stop could be determined by a timer, counting engine ignition pulses after release of trigger 712, or established via a resistor-capacitor circuit (RC circuit) or equivalent. If an RC circuit is used, a user-adjustable timed delay stop could be provided if a variable resistor (i.e., rheostat) is used. In this way, engine 610 is not unnecessarily shut down when the user only briefly releases trigger 712, thereby avoiding overly-frequent restarts of engine 610 during operation. Such a timed delay stop could also be used in combination with an automatic throttle control mechanism to lower engine speed and reduce noise and fuel consumption during the timed delay. If the user wishes to shut down engine 610 before the timed delay period expires, a manual stop button 731 (e.g. push button, toggle switch, other user interface) is provided. Similarly, a manual start switch (e.g., button 634) could also be added to engine 610 to serve as an optional or back-up start system to the trigger-actuated engine starting system.
In some embodiments, the engine 610 is stopped in response to a detected change in engine load and/or speed, rather than, or in addition to, a detected change in flow and/or pressure. For example, when the engine 610 is running and the trigger 712 is pulled to allow flow through the spray gun 714, the engine load increases and the engine speed decreases due to the increased load (restriction) on the pump 713. The increased engine load results in increasing the throttle (e.g., opening the throttle valve). When the trigger 712 is subsequently released, the engine load decreases and the engine speed increases due to decreased load (restriction) on the pump 713. The decreased engine load results in decreasing the throttle (e.g. closing the throttle valve). Because of the changes in throttle position, engine load, and engine speed in response to the trigger state (i.e., open or closed), the change in engine load and/or engine speed can be used as an input for turning off the engine 610. This can be accomplished by detecting movement of the throttle valve or an associated throttle linkage and/or detecting the change in engine speed with a speed sensor (e.g., via ignition pulses, speed sensor 820 described below, or other appropriate sensor for detecting engine speed). The detection can be accomplished by various types of switches, including proximity switches, limit switches, magnetic reed switches, snap action switches, etc. Detecting the movement of the throttle from open to closed with a switch or detecting the change in engine speed with a speed sensor could either directly turn off the engine 610 or start an off delay timer similar to those described elsewhere in the application. A flow sensor 727 indicating that the detected flow is below the threshold flow, a switch detecting the movement of the throttle from open to closed, a speed sensor detecting the change in engine speed, and/or a pressure sensor 729 detecting an appropriate change in pressure (e.g., above or below a threshold) are ways of detecting a stopped flow or zero flow condition. A running engine 610 may be stopped in response to detecting a stopped flow condition with any of these methods.
An additional advantage of the timed delay stop feature is potential elimination of the need for a thermal bypass system in the pump. In conventional pressure washer systems, when the trigger is released while the engine is running, the water in the pump recirculates under pressure. This condition causes the recirculating water in the pump to become increasingly hot over time. Excessively hot water may cause permanent damage to the pump components. To resolve this problem, most conventional pressure washers are equipped with a thermal bypass system. When the water temperature reaches a critical temperature (typically 140° F.), the thermal bypass system bleeds the high temperature water out of the pump and to the ground. After cool water enters the pump and reduces the recirculating water temperature, the thermal bypass system halts the hot water bleed-off. If the timed delay stop described above is set shorter than the time required for the recirculating water in the pump to reach critical bleed-off temperature (typically 90 seconds), then a thermal bypass system would not necessarily be required.
Another advantage of the trigger-actuated engine starting system described above may be a decreased reliance on a pressure-relieving unloader valve during engine start-up. In conventional pressure washer systems, water is provided to the water pump prior to engine start-up and before the spray gun's trigger is actuated, creating a pressure within the water pump that must be relieved by an unloader valve in order to ease engine starting. However, with the trigger-actuated engine system described above, this unloader valve could be eliminated, as the trigger actuation itself relieves the water pressure built up within the water pump (via initiating water flow) prior to the engine being started.
Yet another advantage of the trigger-actuated engine starting system described above may be decreased pump damage caused by a user manually starting the pump without the water source connected to the pump inlet. In conventional pressure washer systems, the engine can be manually started regardless of whether the operator has connected the water source to the pump inlet. If the pump is run without a water supply, the pump may be permanently damaged in a short period of time (e.g., 30 seconds) due to high internal friction and temperatures. Using the trigger-actuated starting system described above, the engine cannot be started unless a water source is connected to the pump inlet, as water flow (and/or pressure) must be sensed by a flow sensor (and/or pressure sensor) to enable starting.
In accordance with the embodiments described above, a trigger-actuated engine starting system may reduce fuel consumption and eliminate noise generated by a gas pressure washer system when not in use, as needless engine operation can be avoided when the user is not directly activating the trigger to spray water.
Referring to FIG. 14, in some embodiments, the trigger-actuated engine starting system may further include a removable disable device 733. The removable disable device 733 is configured to disable (e.g., stop, turn off, etc.) operation of the engine 610 if the user is not in proximity to the pressure washer 710. For example, the removable disable device 733 may be provided in the form of a card, medallion, fob, or other device held or otherwise attached to the user (e.g., with a wrist band, clip, etc.). The removable disable device 733 is coupled to a socket or port 735. This coupling can be physical (e.g. by a tether, cable, cord, chain, etc.) or electronic (e.g., by a wired conductor or wirelessly). The port 735 may be located on the body of the pressure washer 710 (e.g., on the frame 711 or the engine 610) or on the spray gun 714. If the user moves far enough away from the port 735 to decouple the removable disable device 733 from the port 735, an electric circuit is broken to turn off the engine 610 or a signal is generated to turn off the engine 610.
Referring again to FIG. 13, block 744 allows for an outlet capable of trickle charging battery 622 through the use of excess ignition energy may be included. According to one exemplary embodiment, the battery 622 may be charged through the use of ignition primary pulses. The running state/engine speed/rpms of engine 610 are conventionally monitored by reading ignition primary pulses, wherein each ignition primary has a sequence of positive and negative pulses. The excess ignition energy (e.g., positive primary pulses) is not needed/used for production of a spark to fire the engine, so the energy/current from the positive primary pulses may be used for other uses (e.g., monitoring the rpms). In this instance, there is enough energy from the positive primary pulses to both monitor the engine's rpms and trickle charge battery 622. Thus, after the engine 610 has run for a certain period of time (e.g., 12-15 minutes, more or less time as appropriate), the positive primary pulses provide enough energy to replenish the energy used during one starting/cranking cycle, thereby eliminating the need for the user to recharge battery 622 via other means. Alternatively, the battery 622 may be charged by the engine alternator, the starter motor running in a generator mode, or harvesting energy from engine vibration or thermal energy created by operation of the engine and/or pressure washer.
FIG. 15 illustrates an exemplary method 740 for controlling the engine of a pressure washer. With the engine (e.g., engine 610) and the water pump (e.g. water pump 713) off (step 745) and the pressure washer (e.g., pressure washer 710) not connected to a fluid supply (e.g., fluid supply 725), there is no water flow (e.g., substantially no flow) in the fluid system (e.g., supply hose 723, water pump 713, delivery hose 715, and spray gun 714) and the water pressure in the fluid system is zero (e.g., substantially zero). After the pressure washer is connected to the fluid source, and if necessary, the fluid source is turned on, the fluid source fills the fluid system and water pressure in the system builds. A pressure sensor (e.g., pressure sensor 729) detects the water pressure (e.g., pressure differential, static pressure, dynamic pressure, fluid pressure, etc.) and provides a signal that indicates when threshold water pressure is reached (e.g., when the water pressure is above a threshold pressure or when the pressure differential meets a threshold differential) (step 750) in the fluid system (e.g., at or near the line pressure provided by the fluid supply 725). When a user actuates the trigger, water is allowed to flow from the spray gun and through the other components of the fluid system. A flow sensor (e.g., flow sensor 727) detects the water flow (e.g., flow rate, flow volume) and provides a signal that indicates threshold water flow is present in the system (e.g., when the water flow is above a threshold flow) (step 755). The threshold flow may be set at a value where that water flow at the threshold is sufficient to supply the water pump with sufficient water to run. Steps 750 and 755 can be considered to be in series, such that threshold pressure in the system must be achieved before flow in the system is considered. Although illustrated and described with the pressure sensor checked first and the flow sensor checked second, the order may be reversed. Alternatively, steps 750 and 755 can be performed in parallel to each other so that only one needs to be satisfied to indicate the engine is ready to start. In some embodiments, only one of the flow sensor and the pressure sensor is used.
When the flow sensor indicates threshold flow and the pressure sensor indicates threshold water pressure, the engine is ready to be started. In some embodiments, an on delay timer is provided to ensure that accidental or unintended actuation of the trigger does not start the engine (step 760). The on delay timer requires the flow sensor to indicate threshold water flow for a predetermined amount of time (e.g., 0.5, seconds, 1 second, 1.5 seconds, 3 seconds, 5 seconds, other greater or lesser values) before the starter motor (e.g., starter motor 120) is turned on to start the engine. In some embodiments, the on delay timer requires both the flow sensor to indicate threshold water flow and the pressure sensor to indicate threshold water pressure for the predetermined amount of time. Once the predetermined amount of time is met, the starter motor is turned on (step 765). In other embodiments, the on delay timer is omitted and the starter motor is turned on (step 765) as soon as the flow sensor indicates threshold flow and the pressure sensor indicates threshold pressure. In embodiments in which pressure sensing is omitted and only flow sensing is used, the use of the on delay timer helps to ensure that inadvertent or unintentional actuation of the trigger does not start the engine.
The starter motor rotates the crankshaft of the engine to start the engine. Next, whether the engine is successfully started is detected (step 770). This can be done in one or more appropriate ways. For example, a speed sensor (e.g., a governor) can detect when the engine speed meets a threshold speed indicative of the engine being started. As another example, ignition pulses can be used to determine if the engine speed meets the threshold speed. When a successful engine start is detected, the starter motor is turned off (step 780).
In some embodiments, a starter motor cranking timer is provided to ensure that the starter motor is not running for more than a predetermined time (e.g., 5 seconds, 10 seconds, other greater or lesser values) in an unsuccessful attempt to start the engine (step 775). If the predetermined time elapses before the engine start is detected, the starter motor cranking timer turns the starter motor off (step 781). After the starter motor is turned off, the off delay timer is reset (step 782). Next, the flow sensor is checked to compare the detected flow to the threshold hold flow (step 783). Step 783 is dwelled on until the detected flow is below the threshold flow, at which point the starting sequence can be reinitialized from step 745. Steps 781-783 ensure that the user fully releases the trigger, allowing the flow to drop below the threshold flow, before being able to reinitialized the starting process. In some embodiments, pressure sensing is used in place of or in addition to flow sensing. In other embodiments, the starter motor cranking timer is omitted and the starter motor will run until the engine start is detected.
Once the engine is started, the engine will drive the water pump to provide pressurized water to the spray gun. When the user releases the trigger of the spray gun with the engine on, the flow through the system will decrease and stop. When the flow sensor detects flow below the threshold flow (e.g., a no flow condition) (step 785), the engine is turned off. In some embodiments, pressure sensing is used in addition to or in place of flow sensing. For example, in some embodiments, the engine is turned off in response to the pressure sensor detecting pressure below a threshold pressure (e.g., if the pump inlet is disconnected from the fluid supply). In some embodiments, as illustrated in FIG. 15, an off delay timer is provided to allow the user to interrupt use of the spray gun without turning off the engine (step 790). The off delay timer requires the flow sensor to detect flow below the threshold water flow (step 785) for a predetermined amount of time (e.g., 5 seconds, 10 seconds, 15 seconds, other greater or lesser values) before turning off the engine. The predetermined amount of time for the off delay timer may be set by the user. Once the predetermined amount of time is met, the engine is turned off (step 745). In some embodiments, the off delay timer is reset when the flow sensor detects flow above the threshold water flow while the off delay timer is running (step 787). In this way, the user can reset the timer by re-actuating the trigger and restarting fluid flow and continue to use the pressure washer without having to restart the engine. In some embodiments, pressure sensing is used in addition to or in place of flow sensing, with the timer started, stopped, and reset in response to changes in detected pressure and/or detected pressure relative to one or more threshold pressures. In some embodiments, the engine speed is reduced (e.g., by an automatic throttle system), while the off delay timer is running (step 791). This reduces noise and fuel consumption while the off delay timer is running.
A manual stop (e.g., manual stop button 731) is provided so that the user may always manually stop the engine (step 795).
According to an exemplary embodiment, the electrical control circuits shown in FIGS. 10-11, 13, and 13A and the method shown in FIG. 15 are contained on or implemented by non-programmable circuitry, circuit boards, or a processing circuit. The hard-wired logic, circuitry, and processing circuit are collectively referred to as a “controller” (e.g., controller 132 shown in FIG. 14). A processing circuit can include a processor and memory device. Processor can be implemented as a general purpose processor, an application specific integrated circuit (ASIC), one or more field programmable gate arrays (FPGAs), a group of processing components, or other suitable electronic processing components. Memory device (e.g., memory, memory unit, storage device, etc.) is one or more devices (e.g., RAM, ROM, Flash memory, hard disk storage, etc.) for storing data and/or computer code for completing or facilitating the various processes, layers and modules described in the present application. Memory device may be or include volatile memory or non-volatile memory. Memory device may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described in the present application. According to an exemplary embodiment, memory device is communicably connected to processor via processing circuit and includes computer code for executing (e.g., by processing circuit and/or processor) one or more processes described herein. In some embodiments, each circuit or another such circuit is configured to detect when the bail closes (or opens) a switch (see, e.g., switch 518 as shown in FIG. 5). In other embodiments, a circuit is configured to sense when the brake is pulled (see, e.g., brake pad 514 as shown in FIG. 5), and then to enable ignition of the engine. In other contemplated embodiments, a circuit may be further configured to sense vibration of the engine or Venturi vacuum strength in the carburetor, and cut power to the motor when the associated information indicates that the engine is running.
According to an exemplary embodiment, the circuits shown in FIGS. 10-11, 13, and 13A and the method shown in FIG. 15 are contained on or implemented by non-programmable circuitry, circuit boards, or a processing circuit (e.g., controller 132) that are integrated with a component of the engine, and may be fully powered by the energy storage device 130 or 622 or other on-board source. The various ways of implementing these controls (e.g., hard-wired logic, non-programmable circuitry, and processing circuit) are collectively referred to as a “controller.” Accordingly, the controller may require no electrical interface or connection to components of the lawn mower or other outdoor power equipment aside from those carried by or integrated with the engine. No additional wiring or hook ups are required. Accordingly, the assembly process for the associated outdoor power equipment may be improved, as discussed above.
Alternatively, in accordance with another exemplary embodiment, the circuits shown in FIGS. 10-11, 13, and 13A and the method shown in FIG. 15 may be contained on or implemented by non-programmable circuitry, circuit boards, or a processing circuit within the housing of the energy storage device (see, e.g., energy storage device 130 and removable energy storage device 622), and may be fully powered by the energy storage device (e.g., battery or other power source). The various ways of implementing these controls (e.g., hard-wired logic, non-programmable circuitry, and processing circuit) are collectively referred to as a “controller.” As is known, energy storage devices generally have integrated circuitry contained therein that is configured to monitor operating variables of the energy storage device (current, voltage, etc.) related to its charge state. Thus, the addition of the circuits of FIGS. 10-11, 13, and 13A or the method of FIG. 15 to the existing circuit board(s) or on an additional circuit board within the housing of the energy storage device is possible. The controller also receives an existing engine speed sensor input. In this way, the controller may require no electrical interface to components of the lawn mower or other outdoor power equipment, and no additional wiring or hook ups are necessary.
Alternatively, in accordance with another exemplary embodiment, the circuits shown in FIGS. 10-11, 13, and 13A and the method shown in FIG. 15 may be contained on or implemented by non-programmable circuitry, circuit boards, or a processing circuit within the housing of the receiving port 626 that receives the removable energy storage device 622. The various ways of implementing these controls (e.g., hard-wired logic, non-programmable circuitry, and processing circuit) are collectively referred to as a “controller.” This eliminates the need to include the circuitry or controller in each removable energy storage device 622 that may be used with the outdoor power equipment. Also, this provides original equipment manufacturers (“OEMs”) with a modular electric start system where the receiving port 626 can be incorporated into the final product at location of the OEM's choosing and not be limited to a location on the engine 610.
Accordingly, the assembly process for the associated outdoor power equipment may be simplified and improved. Furthermore, the circuits of FIGS. 10-11, 13, and 13A and the method of FIG. 15 are only exemplary, and the specifics of the non-programmable circuitry may be altered to optimize the integration of their functionality onto the existing circuit board(s) or additional circuit board(s) within the energy storage device.
Referring now to FIG. 16, outdoor power equipment 810 is illustrated schematically. Outdoor power equipment 810 is similar to outdoor power equipment 410 described above.
Outdoor power equipment 810 includes an engine 812 and an implement 814 (e.g., mower blade, pump, auger, tiller, alternator, brush, log-splitter, etc.) driven by the engine 812. In some embodiments, an electric motor 816 (e.g., a starter motor) is coupled to the engine 812, and the implement 814 is coupled to a power takeoff 818 of the engine 812. A speed sensor 820 may be coupled to the engine 812 to detect the speed of the engine 812. A run sensor 822 is configured to detect when the implement 814 is in a ready-to-run condition. Depending on the type of outdoor power equipment 810, the run sensor 822 can take different forms. For example, the run sensor 822 may be a switch configured to detect the state (e.g., engaged or disengaged) of a brake or clutch (e.g., for a lawn mower), a switch configured to detect operator presence in the operating position (e.g., a seat switch on a tractor or a hand-actuated switch or bail on a handle), an enable fob or key configured to allow the engine 812 to start when actuated or present and prevent the engine 812 from starting when not actuated or present, a switch configured to sense water or another fluid (e.g., a capacitive water detection sensor, a pressure sensor, a flow sensor) to ensure that a pump has sufficient fluid to operate safely (e.g., for a pressure washer or waste pump).
For example, in a lawn mower including a mower blade as the implement 814, the run sensor 822 detects when a brake that selectively prevents the blade from rotating is in a released position so that the blade is allowed to rotate. The mower blade is in the ready-to-run condition when the brake is released. In another example, in a pressure washer including a fluid pump as the implement 814, the run sensor 822 detects a threshold fluid flow through the fluid pump to a spray gun. The fluid pump is in the ready-to-run condition when the threshold fluid flow is detected (e.g., by flow rate, by flow volume, by fluid pressure, etc.) that is indicative of sufficient fluid supplied to the fluid pump to allow for operation of the fluid pump. In another example of a pressure washer including a fluid pump as the implement 814, the fluid pump is in the ready-to-run condition when the run sensor 822 detects the presence or actuation of an enable key or fob. In some embodiments, the outdoor power equipment 810 includes more than one run sensor 822 and all the run sensors 822 must be satisfied before the implement 814 is considered to be in the ready-to-run condition.
A release mechanism 826 (e.g., a bail for a lawn mower, a spray gun trigger for a pressure washer, a start button or switch, etc.) is movable to an engaged position to put the implement 814 in the ready-to-run condition. In a lawn mower example, the release mechanism 826 can be a bail connected to a handle 824 and the bail is configured to allow a user to release the brake by moving the bail to the engaged position. The run sensor 822 detects that the brake is released, thereby putting the mower blade into the ready-to-run condition. If the bail is not moved to the engaged position (e.g., when the bail is blocked by an interlock as described above), the brake is not released and the mower blade will not be put in the ready-to-run condition.
In a pressure washer example, the release mechanism can be the trigger of a spray gun fluidly connected to a fluid pump. The trigger is configured to allow fluid to flow through the spray gun when the trigger is moved to the engaged or open position. The trigger in the open position allows a threshold fluid flow through the fluid pump that is indicative of the fluid pump in the ready-to-run condition. The run sensor 822 detects the threshold fluid flow. If the threshold fluid flow is not established, the fluid pump is not in the ready-to-run condition and the ready-to-run condition is not detected by the run sensor 822. For example, this may happen if the pressure washer is not connected to a fluid supply (e.g., a water faucet or outlet), or there is a leak or loose connection between the pressure washer and a fluid supply. Alternatively, in some embodiments, the release mechanism 826 can be a start actuator (e.g., a start push-button or key-switch).
Outdoor power equipment 810 also includes a battery 828 for powering the motor 816 and other components of the outdoor power equipment 810 and an electric start control module 830 for operating the motor 816. As illustrated in FIG. 16, the control module 830 is spaced apart from (separate from, distinct from) the engine 812. The control module 830 is configured to receive inputs associated with the release mechanism 826 and the run sensor 822. In some embodiments, when the release mechanism 826 is moved to the engaged position, the release mechanism 826 actuates a switch 832, which provides a signal to the control module 830. The signal may be provided via a mechanical linkage, wirelessly, a hardwired electrical connection, or otherwise. The control module 830 checks the run sensor 822 to determine if the implement 814 is in the ready-to-run condition. When both the switch 832 and the run sensor 822 provide signals or inputs indicating the implement 814 is in the ready-to-run condition, the control module 830 then actuates the motor 816 to start the engine 812. Additional information or control logic may also be configured to start the engine in combination with the status of the switch 832, the run sensor 822 and/or other factors. Movement of the release mechanism 826 to the engaged position can simultaneously provide a start signal to the control module 830 via the switch 832 as well as put the implement 814 in the ready-to-run condition as detected by the run sensor 822, such that no additional user operations are required to start the engine 812.
According to an exemplary embodiment, the control module 830 is configured to receive additional inputs from the speed sensor 820. The speed sensor 820 provides the control module 830 with information associated with the speed of the engine 812. In some embodiments, the speed sensor 820 is configured to detect when the engine 812 is running at a threshold speed. When the engine 812 is running at the threshold speed, the control module 830 then turns off the motor 816 (e.g., disengages, disconnects, cuts power to, etc.). In some embodiments, the speed sensor 820 is a component of or otherwise coupled to an ignition coil of the engine to detect the engine speed. In other embodiments, the speed sensor 820 is a component of or otherwise coupled to a governor to detect the engine speed.
In contemplated embodiments, the control module 830 associated with the start system may receive additional or different inputs used to control starting of the engine, such input from a sensor configured to indicate whether the outdoor power equipment has moved recently. Movement of an axle or wheels of such outdoor power equipment may trigger a sensor that provides a signal to the control module. The signal, in combination with an electric timer providing time-related context for the movement, may serve as an additional indicator that the operator intends to activate the engine. In contemplated embodiments, the control module 830 includes a timer and is configured to deactivate the motor if the engine has not started within a predetermined amount of time. In some contemplated embodiments, the control module 830 includes a temperature sensor and is configured to prime the engine with an automated primer pump or adjust the choke or throttle plate if ambient temperature is above or below a predetermined temperature, if a portion of the engine is above or below a predetermined temperature, or if the difference between ambient and engine temperature is above or below a predetermined value. In contemplated embodiments, the control module 830 may also provide a signal output to the operator, such as a visible indicator on a display coupled to the handle or engine, or an audible alert. In some such embodiments, the signal output may include as an error message, a low-fuel message, a replace-oil message, or another such message.
Referring now to FIG. 17, the control module 830 is illustrated according to an exemplary embodiment. The control module 830 includes a housing 834, a controller 836 configured to implement control logic for operation of the outdoor power equipment 810, a connector 838 configured to be electrically coupled to a release assembly wiring harness 840, and a connector 842 configured to be electrically coupled to the electric motor 816. The connectors 838 and 842 are located on opposite sides of the housing 834 to accommodate connecting the control module 830 inline with one or more wiring harnesses. The controller 836 is positioned within the housing 834. In some embodiments, the control module 830 includes a connector 844 configured to be electrically coupled to the speed sensor 820. The connector 844 is located on an opposite side of the housing 834 from one of the connectors 838 and 842. In some embodiments, the switch 832 is a component of the control module 830 and is positioned within the housing 834.
In some embodiments, the control module 830 also includes one or more connectors 846 and 848 configured to be electrically coupled to a run sensor 822 to provide inputs from the run sensor 822 to the controller 836. The run sensors 822 are considered to be connected in parallel to the control module 830. Alternatively, more than one run sensor 822 can be connected to a single connector 846 so that the controller 836 receives a single run sensor input, but only when all of the run sensors 822 are satisfied that the implement 814 is in the ready-to-run condition. In such an embodiment, the run sensors 822 are considered to be connected in series to the control module 830. In some embodiments, the input from the run sensor is provided via a wiring harness (e.g., the release assembly wiring harness 840), electrically coupled to connectors 838 or 842, so no separate connector for a run sensor is required to provide a run sensor input to the controller 836. Each connector 846 and 848 is located on an opposite side of the housing 834 from one of the connectors 838 and 842.
The controller 836 may include components configured to implement hard wired control logic or a processing circuit. The processing circuit can include a processor and memory device. The processor can be implemented as a general purpose processor, an application specific integrated circuit (ASIC), one or more field programmable gate arrays (FPGAs), a group of processing components, or other suitable electronic processing components. The memory device (e.g., memory, memory unit, storage device, etc.) is one or more devices (e.g., RAM, ROM, Flash memory, hard disk storage, etc.) for storing data and/or computer code for completing or facilitating the various processes, layers and modules described in the present application. The memory device may be or include volatile memory or non-volatile memory. The memory device may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described in the present application. According to an exemplary embodiment, the memory device is communicably connected to the processor via the processing circuit and includes computer code for executing (e.g., by processing circuit and/or processor) one or more processes described herein.
The release assembly wiring harness 840 electrically couples the electric motor 816, the run sensor 822, and the battery 828 together. For example, in the lawn mower example, the release assembly wiring harness is the bail wiring harness electrically connecting the release assembly including the release mechanism or bail 826 to the electric motor 816 and the motor 816. By connecting the connector 838 to the release assembly wiring harness 840 (e.g., the bail wiring harness of a lawn mower) and connecting the connector 842 to the electric motor 816, the control module 830 is electrically coupled to the release assembly wiring harness 840.
By connecting the control module 830 to existing wiring, outdoor power equipment configured to be pull started (e.g., by a recoil starter) is converted to electric start. The control module 830 is easily connected inline with existing wiring, thereby eliminating the need for adding additional wiring or significantly rerouting wiring for an electric start outdoor power equipment model as compared to a pull start outdoor power equipment model. The control module 830 is relatively small in size and light weight. This allows the control module 830 to be connected to existing wiring and not physically mounted to any other component of the outdoor power equipment. That is, once connected to the existing wiring, the control module 830 is free to remain otherwise unsupported (e.g. dangle with the existing wiring harnesses) by a mount, bracket, or other physical support structure on the outdoor power equipment. The control module 830 allows a manufacturer to provide an outdoor power equipment product available as either a pull start model or an electric start model while simplifying the manufacturing process. The manufacturing process is simplified because the control module 830 that converts the outdoor power equipment to electric start is connected to existing components (i.e., the release assembly wiring harness 840 and the electric motor 816) of the pull start outdoor power equipment and does not require a separate physical mounting structure.
Alternatively, in accordance with another exemplary embodiment, the circuits shown in FIGS. 10-11 and 13 and the method shown in FIG. 15 may be contained on or implemented by an electric start control module 830 as described above. The hard-wired logic, circuitry, and processing circuit are collectively referred to as a “controller.”
The construction and arrangements of the starter system for an engine, as shown in the various exemplary embodiments, are illustrative only. Although only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter described herein. Some elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. The order or sequence of any process, logical algorithm, or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes and omissions may also be made in the design, operating conditions and arrangement of the various exemplary embodiments without departing from the scope of the present invention.
The present disclosure contemplates methods, systems and program products on any machine-readable media for accomplishing various operations. The embodiments of the present disclosure may be implemented using existing computer processors, or by a special purpose computer processor for an appropriate system, incorporated for this or another purpose, or by a hardwired system. Embodiments within the scope of the present disclosure include program products comprising machine-readable media for carrying or having machine-executable instructions or data structures stored thereon. Such machine-readable media can be any available media that can be accessed by a general purpose or special purpose computer or other machine with a processor. By way of example, such machine-readable media can comprise RAM, ROM, EPROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store desired program code in the form of machine-executable instructions or data structures and which can be accessed by a general purpose or special purpose computer or other machine with a processor. When information is transferred or provided over a network or another communications connection (either hardwired, wireless, or a combination of hardwired or wireless) to a machine, the machine properly views the connection as a machine-readable medium. Thus, any such connection is properly termed a machine-readable medium. Combinations of the above are also included within the scope of machine-readable media. Machine-executable instructions include, for example, instructions and data which cause a general purpose computer, special purpose computer, or special purpose processing machines to perform a certain function or group of functions.
Although the figures may show or the description may provide a specific order of method steps, the order of the steps may differ from what is depicted. Also two or more steps may be performed concurrently or with partial concurrence. Such variation will depend on various factors, including software and hardware systems chosen and on designer choice. All such variations are within the scope of the disclosure. Likewise, software implementations could be accomplished with standard programming techniques with rule based logic and other logic to accomplish the various connection steps, processing steps, comparison steps and decision steps.

Claims

What is claimed is:

1. A pressure washer comprising:

an engine;

a water pump driven by the engine, the water pump having a low pressure side and a high pressure side, the high pressure side providing pressurized water;

a starter motor coupled to the engine to start the engine;

an energy storage device electrically coupled to the starter motor;

a spray device including an activation device for starting and stopping a flow of water from the spray device;

a pressure sensor located at the low pressure side, the pressure sensor configured to indicate a water pressure relative to a threshold pressure;

a flow sensor located at the low pressure side, the flow sensor configured to indicate a water flow relative to a threshold flow; and

wherein, with the engine off, the starter motor starts the engine when the pressure sensor indicates the water pressure is above the threshold pressure and the flow sensor indicates the water flow is above the threshold flow.

2. The pressure washer of claim 1, wherein, with the engine on, the engine is stopped when the flow sensor indicates the water flow is below the threshold flow.

3. The pressure washer of claim 1, wherein, with the engine on, when the flow sensor indicates the water flow is below the threshold flow for a predetermined amount of time, the engine is stopped when the predetermined amount of time is met.

4. The pressure washer of claim 3, wherein the engine speed is reduced during the predetermined amount of time.

5. A pressure washer comprising:

an engine;

a water pump driven by the engine, the water pump providing pressurized water;

a starter motor coupled to the engine to start the engine;

an energy storage device electrically coupled to the starter motor;

a pressure sensor configured to indicate a water pressure relative to a threshold pressure;

a flow sensor configured to indicate a water flow relative to a threshold flow; and

a controller configured to control the operation of the engine, wherein, with the engine off, the controller activates the starter motor to start the engine when the pressure sensor indicates the water pressure is above the threshold pressure and the flow sensor indicates the water flow is above the threshold flow.

6. The pressure washer of claim 5, wherein with the engine on, the controller is configured to stop the engine when a stopped flow condition is detected.

7. The pressure washer of claim 5, wherein the controller is configured to implement an off delay timer set for a predetermined amount of time, the off delay timer runs when the flow sensor indicates the water flow is below the threshold flow; and

wherein the controller is configured to stop the engine when the predetermined amount of time is met.

8. The pressure washer of claim 7, wherein the off delay timer is reset when the flow sensor indicates the water flow is above the threshold flow before the predetermined amount of time is met.

9. The pressure washer of claim 5, wherein the controller is incorporated into the engine.

10. The pressure washer of claim 5, wherein the controller is incorporated into the energy storage device.

11. The pressure washer of claim 5, wherein the energy storage device is removably coupled to a receiving port and the controller is incorporated into a housing of the receiving port.

12. The pressure washer of claim 11, wherein the energy storage device is rechargeable.

13. The pressure washer of claim 5, wherein the controller is incorporated into an electric start control module separate from the engine and the energy storage device.

14. The pressure washer of claim 5, wherein the controller comprises non-programmable circuitry having discrete components.

15. The pressure washer of claim 14, wherein the discrete components include:

a starter motor activation circuit configured to activate the starter motor to start the engine when the pressure sensor indicates the water pressure is above the threshold pressure and the flow sensor indicates the water flow is above the threshold flow; and

an off time delay circuit configured to implement a timer that runs when the flow sensor indicates the water flow is below the threshold flow and to stop the engine when the timer expires.

16. The pressure washer of claim 5, wherein the controller does not include a microcontroller.

17. The pressure washer of claim 5, wherein the controller is configured to implement an off delay timer set for a predetermined amount of time;

wherein the off delay timer is started in response to a change in pressure indicated by the pressure sensor; and

18. A pressure washer comprising:

an engine;

a water pump driven by the engine, the water pump providing pressurized water;

a starter motor coupled to the engine to start the engine;

an energy storage device electrically coupled to the starter motor;

a sensor configured to indicate a water flow or a water pressure relative to a threshold; and

non-programmable circuitry configured to control the operation of the engine, the non-programmable circuitry including a starter motor activation circuit configured to activate the starter motor to start the engine when the sensor indicates the water flow above the threshold or the water pressure above the threshold.

19. The pressure washer of claim 18, wherein the sensor comprises a flow sensor configured to indicate the water flow relative to the threshold; and

wherein the non-programmable circuitry further includes an off time delay circuit configured to implement a timer that runs when the flow sensor indicates the water flow is below the threshold flow and to stop the engine when the timer expires.

20. The pressure washer of claim 19, wherein the non-programmable circuitry further includes an on delay timer circuit configured to implement a timer that delays activation of the starter motor until the flow sensor indicates the water flow is above the threshold flow for a predetermined amount of time.

21. The pressure washer of claim 18, wherein the non-programmable circuitry further includes a crank limiting timer circuit configured to implement a timer that runs while the starter motor is activated and to stop the starter motor when the timer expires.