WO2011000611A1 - Starting device for an internal combustion engine and method for operating a starting device - Google Patents

Abstract

The invention describes a starting device (1) for an internal combustion engine, in particular of a vehicle, having a starter motor (2), a switching relay (3), a starter controller (5) for the switching relay (3) and an energy source. In order to use a starting device (1) so as to conserve resources and obtain a longer life cycle, the starting device (1) is constructed with a power regulating device for the starter motor (2).

Description

 description

title

 Starting device for an internal combustion engine and method for operating a

Startvorrichtunq

State of the art

The invention relates to a starting device for an internal combustion engine, in particular of a vehicle, with a starter motor, a switching relay, a

Starter control for the switching relay and a power source. The invention further relates to a method for operating a starting device with a starter motor for starting an internal combustion engine, in particular a vehicle, wherein the starter motor is switched on and off by a starter control for starting the internal combustion engine.

There are known starting devices with a starter motor for starting an internal combustion engine. The starting devices are either actuated in a defined manner by an ignition switch or controlled by a control activated by an activation button by the driver. It is also known, in vehicles with a start-stop device to control the starting device defined by a controller, for example, after a stop of the internal combustion engine to start this again for driving recording. DE 102 31 0 88 A1 describes a switching device for switching on a

Starter motor with two transistors and each with a means of checking the functionality.

It is an object of the invention to provide a starting device, a method for its operation and a computer program product of the type mentioned in the introduction. terzubilden that a starting device is resource-saving with a longer life can be used.

Disclosure of the invention

According to the invention the object is achieved by the subject matter of claims 1 and 8. The dependent claims define preferred embodiments of the invention. It is an idea of the invention to provide only as much electric power to the starter motor for a starting operation of the starting device as is actually required for starting the engine. This has the advantage that electrical power is handled efficiently and resource-conserving the components are claimed and acted upon. It is thus a performance surplus avoided on the part of the starter motor when the

 Starter motor is just loaded with as much electrical power as is required for starting the internal combustion engine. This leads to a significant reduction in the wear on the starter pinion, which is meshed into a ring gear of the internal combustion engine for starting. The reduction of electrical

Performance on the actually required power also protects the carbon brushes in the electrical machine and the bearings, as well as in the switching relay for controlling the starter motor contact pieces.

The object is thus achieved in that the starting device is formed with a power regulating device for the starter motor. The power regulation device thus adapts the electrical power to the corresponding operating requirements. The power regulation device may be, for example, an electronic starter control, which reduces the current.

For example, the power can be regulated by placing resistors in front of it. However, this has the disadvantage that such power resistors are high electrical consumers and thus do not work resource-conserving with respect to the electrical energy.

According to a preferred embodiment of the invention, the power regulating device is provided with a starter control having at least one power switch and in each case a separately assigned energy source for increasing the formed on the starter motor available electrical power. This has the advantage that the starter control by at least one additional circuit breaker with the associated energy source, for example in the form of a battery, the electric power switches on. To simplify the power regulation, the power is switched in discrete values and not variable.

A variable increase of the electrical power is more expensive to implement and therefore more expensive in contrast to a simple connection of a discrete electrical power in the form of a battery. Therefore, the preferred embodiment is the connection of energy sources, each with a discrete energy output. The more circuit breakers are available with each associated energy source, the more differentiated the electrical power can be adapted to the operating requirements. Conveniently, in a simple embodiment, three power switches are provided with three associated power sources. Thus, the operating range of the starting device can be subdivided into three subareas, a first subarea with a minimum required electrical power and a second subarea with an average required electrical power and a third subarea with a maximum required electrical power. According to a further preferred embodiment, the power regulating device has at least one control part, in particular a temperature sensor. By means of the control part, the power range of the starter motor can be divided into operating ranges. By means of the temperature sensor, the operating range of the starter motor can be divided depending on the temperature. The control part measures variable values, while the power regulating device evaluates the values of the control part by means of the starter control and the power regulating device controls the starter motor in certain operating ranges. According to a further preferred embodiment, the power regulating device comprises a time-dependent control part, in particular a timer. By means of a time-dependent control part, the starter motor can be subjected to different powers by the power regulation device in a time-dependent manner during the starting process. Thus, the starter motor can be controlled efficiently, without the on-board network is stressed too much or too much power is unnecessarily withdrawn from the electrical system. - A -

The starter control can also be designed with discrete electrical switching elements or small electromechanical relays and a temperature sensor in bimetal design. Advantageously, the power regulation device is arranged on the positive pole side of the starter motor. Thus, the electrical energy is supplied to the starter motor from the positive pole side.

 Usually starting systems are connected to the ground with the negative pole of the battery. This existing interconnection can thus be accepted without restriction. Alternatively, the power regulator may be located on the negative pole side of

Starter motor can be arranged. The circuit breakers are thus arranged on the negative pole side of the starter motor and cause when closing the circuit breaker, the total resistance is reduced in the main circuit of the starter motor and increases the electrical power by each of the closing of the circuit breaker another energy source in the form of, for example, a battery is switched on. When using a starter with insulated mass, starter housing, engine block of the engine, vehicle frame are arranged isolated. It may be advantageous to arrange the power regulating device on the negative pole side, since on the positive pole side additional switching elements such as e.g. Battery disconnector, line branches to generators and large consumers, etc. are present. These might have to be changed with great effort in order to represent the same function, therefore, here offers the negative pole side.

Preferably, the starting device is connectable to a start-stop control. Thus, the starting device is efficiently supplied with electrical energy, both for a start-up operation in cold, when the starting of the internal combustion engine requires a higher electrical power, since the internal combustion engine has a greater engine torque, when the internal combustion engine is still cold and the engine torque due to the viscosity of in the internal combustion engine engine oil is increased. In a restart in the start-stop operation, the internal combustion engine is already heated, so that the viscosity of the engine oil is significantly improved, so that the engine torque is significantly reduced and the starter motor only a lower electrical power required for starting the internal combustion engine, which is provided and made possible by the power regulating device.

The object is also achieved by a method for operating a starting device, characterized in that the starter motor in the starting process of the power regulated by the

Starter control is controlled. For example, as described earlier, the starter control distinguishes whether the engine has a low engine torque and a medium or increased engine torque to start. Accordingly, the starter control controls the starter motor in a power-regulated manner.

According to a method which further develops the invention, the starter motor is acted upon by the starter control with a defined maximum electrical power depending on, preferably in three, divided operating ranges. The maximum power is limited by the starter, the battery and the line resistance, and the state of charge so here max. 100%, which is not sensed here. The applied to the engine torque, which is referred to as engine torque, is dependent on temperature to a significant extent. It is therefore appropriate to adjust the power of the starter motor accordingly, thus efficiently to provide the starter motor with electrical power. Excessive power leads to unnecessarily high wear on the carbon brushes, in bearings and on the contact pieces on the starter relay. The operating ranges are divided depending on the predetermined number of circuit breakers with associated operating sources. In a threefold division, the following temperature ranges are preferably provided: a first temperature range> 20 ^° C., a second temperature range between 0 ^° C. and 20 ^° C. and a lower temperature range <0 ^° C. The higher the temperature, the lower the required electrical power the electric machine, ie the starter motor. The temperature ranges are specific to the type of vehicle and can be variably adjusted to specific climatic conditions.

According to an alternative or additional method, it may be provided that the starter motor is supplied with electrical power in a regulated manner during the starting process by starter control in time stages. Due to a time-delayed connection by circuit breakers of electrical energy Energy sources, for example in the form of a battery or battery groups, thus a relatively gentle turning is possible, so that the components of the starter, in particular those of the starter, ie the carbon brushes, electrical contacts and the roller freewheel and the teeth are claimed protected.

The object is achieved by a computer program product in that it can be loaded into a program memory with program instructions in order to execute all the steps of a method described above when the computer program product is executed in a starter controller. The computer program product has the advantage that operating ranges are simple, variable and type-specific adjustable. A resource-saving optimization with regard to component wear and electrical power can be calculated and / or determined from empirical values. The computer program product can be adapted to the specific values.

It goes without saying that the features mentioned above and those yet to be explained below can be used not only in the respectively specified combination but also in other combinations.

Brief description of the drawings

The invention will be explained in more detail below with reference to the drawings. Show it:

1 is a schematic circuit diagram of a starting device according to a first embodiment,

2 shows a schematic circuit diagram of a starting device according to a second embodiment,

3 is a table with three different operating ranges,

4 shows a table with three operating ranges dependent on operating times, 5a-c are timing diagrams relating to operating values in the starting operation of the starting device,

6 is a flow chart of a method according to the invention.

Embodiments of the invention

Fig. 1 shows a schematic circuit diagram of a starting device 1 according to the invention for an internal combustion engine, not shown, of a vehicle. The starting device 1 comprises a starter motor 2, which is acted upon by a switching relay 3 with electrical power from a battery 4 as an electrical energy source switchable. The switching relay 3 with a first switching contact Sk1 is controlled by a starter control 5. The shift relay 3 can be referred to as a so-called starter relay, or also as an engagement relay, which includes the function of meshing a starter pinion into the ring gear of the internal combustion engine. The starter relay can be configured in one or two stages. Conventionally, the starter control 5 is, for example, an ignition switch on the ignition lock of a vehicle or an electronic circuit with a switch button. For a start-stop operation is the starter control

5 complex and is in contact with the engine control of the internal combustion engine.

According to the invention, the starting device 1 comprises at least one further second power switch, which is preferably designed as a second switching relay 6 and can also be controlled by the starter control 5. The second switching relay 6 switches with a second switching contact Sk2 to another energy source in the form of a battery 7 and thus reduces the total resistance in the main circuit of the starter motor 2. Thus, a higher power for the starter motor 2 is available, so that the starter motor 2, a higher torque can give, which is required for example due to a higher engine torque of the internal combustion engine.

According to the invention, any further third, fourth, etc., power switches 8 are connected in series behind the first and second power switches 3, 6, each of which switches on an associated energy source, for example in the form of a battery and be controlled by the starter control 5. In the preferred embodiment, a third switching relay 8 with a third switching contact Sk3 is controlled by the starter control 5 and switches a third battery 10 to. The lines each have resistors marked and represented by R _LH i, Rι_ _H2 and R _LH3 . The return on the negative pole side of the starter motor 2 has a resistance R _L R and is represented by a resistance symbol.

 According to an embodiment not shown, the switching contacts 6 and 8 need not be connected in series. In such an embodiment, the batteries via parallel arranged switching contacts 6 and 8 with a common neutral point on the Schaltkontatk 3 can be switched.

The starter controller 5 is connected to a temperature sensor 9 to detect the temperature of the engine to derive therefrom a possible, actual engine torque of the internal combustion engine. The

Motor torque can be calculated either by a temperature dependent formula or by a look-up table, whereby the intermediate values can be interpolated. As an alternative to the temperature sensor 9, the values can be transmitted via an interface, for example from the engine control to the starter control 5, so that an additional temperature sensor 9 in a vehicle is not necessary.

Furthermore, the starter control 5 has a time-dependent control part, preferably in the form of a timer 13, to carry out the method according to the invention, as described below. The starter controller 5 further includes a

Microcomputer with a CPU 1 1 and with a program memory 12.

Fig. 1 shows the arrangement of the first switching relay 3, second switching relay 6 and third switching relay 8, each with the associated power source and the starter control 5 for driving on the positive pole side of the starter motor. The

Starter control 5, together with the switching relays 3, 6, 8 and the batteries 4, 7, 10, a power regulating means for supplying the starter motor 2 defined according to the requirements for starting the internal combustion engine with an electric power. This has the advantage that a considerably higher power surplus is not activated and thus unnecessarily high wear on a starter pinion of the starter motor 2 and on the ring gear of a Internal combustion engine and on the carbon brushes in the starter motor 2 and contact pieces in the switching relay 3, 6 and 8 and unnecessarily high load on the roller freewheel / overrunning clutch are also reduced by the supply of the electrical system from the batteries 4 or 7, the voltage drop during a startup reduced be because the line resistance Rι_m in this

Case only for starter current is effective, but not for the significantly lower power for the remaining consumers, but only the line resistance RI_H2 _, or Rι_ _H3, depending on the interconnection. With this, possibly necessary DC / DC converters for stabilizing the vehicle electrical system voltage can be designed significantly more cheaply, possibly even completely eliminated.

2 shows a schematic circuit diagram of the starting device 1 according to the invention according to FIG. 1, with the difference that the first switching relay 3 and the further switching relays 6 and 8 are arranged as power regulating device on the negative pole side of the starter motor 2. This is a variant of FIG. 1. When using insulated mass start-up systems, i. Starter housing, engine block of the internal combustion engine, vehicle frame, ... are electrically not connected to the negative pole of the battery, such as in construction machinery, marine propulsion, stationary engines, rail vehicles, is advantageous to arrange the power control device on the negative pole side, as on the positive pole side often additional switching elements such eg Battery disconnector, line branches to generators and large consumers, etc. are present. These would u.U. be changed with greater effort to represent the same function, therefore, offers the minus side.

The electrical line to the positive pole of the starter motor 2 has an internal resistance RLH- three lines on the negative pole side of the starter motor 2 have an internal resistance RI_RI _, RLR2 and R | _ _R3 . The starter controller 5 has been omitted for the sake of simplicity. FIG. 3 shows a table with a division of the operating range from the starter motor 2 into three operating ranges B i, n, i n dependent on the temperature. A first temperature range B i comprises a temperature greater than 20 ^° C. of the internal combustion engine. In the first temperature range B i, which is detected via the temperature sensor 9 and detected by the starter controller 5 as such, only the first power switch 3 with the switching contact Sk1 by means of the first according to the stored in the program memory 12 method Switching relay 3 is closed, so that the starter motor 2 is acted upon by a minimal electrical power from the battery 4 and thus protects the starter pinion the ring gear. In this temperature range B i over 20 ⁰ C, the engine torque is lower than at lower temperatures. Thus, electrical power is saved and load on the components is reduced, so that a

Wear is reduced.

A second temperature range B n, in which the starter motor 2 can work in the starting process, for example, between 0 ⁰ C to 20 ⁰ C. Here, according to the table of FIG. 3, the switching contacts Sk1 and Sk2 on the circuit breaker from the first switching relay 3 and second switching relay 6 each closed and the switching contact Sk3 on the third switching relay 8 open. This results in an average power that is higher than in the temperature range> 20 ⁰ C. The starter motor 2 thus outputs an increased torque for increased engine torque due to increased electrical power, characterized in that a second battery 7 parallel to the first Battery 4 is switched by the switch 6.

The table according to FIG. 3 shows a third temperature range B i n with a temperature of less than 0 ° C., in which the starter motor 2 operates. In this third

Temperature range B i n, the switching contact Sk1, Sk2, Sk3 from the first switching relay 3, the second switching relay 6 and the third switching relay 8 are each closed. Thereby, three batteries 4, 7, 10 are connected in parallel as an energy source, which together provide an increased electrical power to the starter motor 2, so that this due to the increased viscosity of the engine oil in the

Internal combustion engine can also start this fast. In addition, the performance of electric batteries in temperature ranges below 0 ⁰ C is greatly reduced, so that also for this reason, the batteries are connected in parallel.

4 shows a further table, according to which the switching contacts Sk1, Sk2, Sk3 are actuated by the switching relays 3, 6, 8 and activated by the starter control 5 as a power regulating device according to a defined program. Table 4 again shows three operating ranges B i, i i, i n, which, like the table according to FIG

Switch contacts in the open and closed state shows, in which case the crisis the timing of the startup process is. In a first time period from t1 to t2, the starter motor 2 is subjected to a low power, which is increased with increasing time from the starting process by connecting the second switching contact Sk2 from a time t2 and from a time t3 by switching a third switching contact Sk3 , Thus, the starter motor 2 is gently turnable and the speed of the starter motor 2 increases slower, the current spike is initially significantly lower, so that the components such as toothing, overrunning clutch, switching contacts including the carbon brushes of the starter motor 2 are claimed much less. Wear is thus clearly reduced.

FIG. 5a shows the switch-on states of the switches 3, 6 and 8 with the switch contacts Sk1, Sk2, Sk3 with increasing time t in the starting process. At time t1, the first switch 3 is closed. At time t2, the second switch 6 is closed and at time t3, the third switch 8 is closed with the switching contact Sk3.

Table 5b shows in accordance with the falling in stages total resistance R ₁ in the main circuit of the starter motor 2 in parallel with the connection of the switching contacts Sk1 to Sk3 at the times t1, t2 and t3.

5c shows a time-current diagram with a current characteristic IE according to the invention corresponding to the switching states as shown in FIGS. 5a and 5b. The switching states produce in the starting process upon execution of the procedure according to the table of FIG. 4 an increase in the starter current IE in stages with significantly lower peak currents l _{e i,} Iε ₂ and I _E3 respectively shortly after switching on at the times t1, t2 and t3 in the power grid. As a result, the electrical system is less loaded overall, so that a start of the internal combustion engine, for example, in a start-stop operation and a simultaneous operation of other electrical consumers is not detected. In addition, the characteristic IH is displayed, which is shown in relation to the characteristic IE. The speed n of the starter motor 2 increases according to the characteristic curve n _E slower compared to the speed characteristic n _H , according to which the starter motor 2 has been charged immediately with maximum electrical power as conventionally according to characteristic I _H. FIG. 6 shows a flow chart according to a preferred embodiment, such as the method in the starter control 5, which is stored in the program memory 12 in the form of a computer program. At a certain time, a start signal, for example, by an ignition switch activated by the driver, which is symbolized by a step S10.

Thereafter, the starter control 5 asks the temperature sensor 9 or via a bus system or via the engine control, the current engine temperature of

Internal combustion engine in a step 20 from.

In a step S30, the temperature of the starter control 5 is notified, so that the starter control 5 makes an evaluation in step S40 and in step S50, according to the table of FIG. 3, decides which switches 3, 6,

8 are closed to start the internal combustion engine.

In a step S60, a first power switch is closed via the switching relay, for example via the first switching relay 3, and the starter motor 2 is started.

In a query step A1 it is checked whether the internal combustion engine is started. If this is the case, which is determined via the control part, the starter motor 2 is switched off by the starter control 5 in a step S70. If the internal combustion engine has not yet started, then a clock starts to run in the query step A1.

If, within a specific time, the internal combustion engine has not yet accelerated to a predefined minimum rotational speed, the method according to the table from FIG. 4 is selected, for example, according to a preferred embodiment. It is thus determined in a step S80 that another, for example a second switch, should be closed. The process returns to the starter control of step 50 and a second switch is closed so that the engine is cranked at an increased power on the starter motor 2. The method continues through steps 60 and query A1. Is the engine still not on one accelerated high speed required so it can be closed by triggering the starter control 5 after a second timeout of another, third power switch 3. This process can be run through within a second, so that a driver takes almost no notice of it.

The starter controller 5 may also include a self-learning function so that it learns independently at which temperatures the engine can be started quickly and with what combination of closed switches, and how many switches can remain open to still successfully start the engine. It is understood that the method shown combined in FIG. 6 in dependence on temperatures and times for switching the switching contacts Sk1 to Sk3 can also be performed separately from a method sequence. The figures show schematic, not to scale representations. Incidentally, reference is made in particular to the drawings of the invention as being similar.

Claims

claims 1 . Starting device (1) for an internal combustion engine, in particular a vehicle, with a starter motor (2), a switching relay (3), a starter (5) for the switching relay (3) and an energy source, characterized in that the starting device (1 ) is designed with a power regulation device for the starter motor (2). 2. Starting device according to claim 1, characterized in that the power Regulation device is a starter control (5) with at least one circuit breaker and each a separate associated energy source for increasing the starter motor (2) available electrical power is formed. 3. Starting device according to claim 1 or 2, characterized in that the power regulating device has at least one control part, in particular a temperature sensor (9). 4. Starting device according to one of claims 1 to 3, characterized marked, that the power regulating device comprises a time-dependent control part. 5. Starting device according to one of claims 1 to 4, characterized in that the power regulating device is arranged on the positive pole side of the starter motor (2). 6. Starting devices according to one of claims 1 to 4, characterized in that the power regulating device is arranged on the negative pole side of the starter motor (2). 7. Starting device according to one of claims 1 to 6, characterized in that the starting device (1) with a start-stop control is connectable. 8. A method for operating a starting device (1) with a starter motor (2) for starting an internal combustion engine, in particular a motor vehicle zeugs, wherein the starter motor (2) by a starter control (5) is switched to start the internal combustion engine, characterized in that the starter motor (2) in the starting process is controlled by the power control of the starter control (5). 9. The method according to claim 8, characterized in that the starter motor (2) is acted upon by the starter control (5) depending on divided operating temperature ranges with a defined maximum electric power. 10. The method according to claim 8 or 9, characterized in that the Starter motor (2) in the starting process by the starter control (5) in power stages with regulated power is applied to electrical power. A computer program product loadable into a program memory (12) with program instructions for carrying out all the steps of a method according to at least one of claims 6 to 9 when the computer program product of a starter controller (5) is executed.