RU2819707C2 - Improved device and method for milk foaming - Google Patents

Abstract

FIELD: food industry.

SUBSTANCE: disclosed is an assembly unit for measuring temperature of a milk foaming device. Assembly includes: a temperature sensor element and a resilient supporting element, comprising a temperature sensor element, and also displaces it in the direction of thermal contact with the lower part of the reservoir; wherein the assembly unit is located in the direction of the end of the protruding portion, which protrudes from the body of the milk foaming device; and the upper surface of the temperature measurement sensor assembly is configured to facilitate the movement of the liquid into the moisture-collecting tray reservoir. Device may include: a steam source; an air source connected to the air introduction module for mixing air and steam; user interface for receiving input commands from a user; wherein the device can be configured by receiving input parameters through the user interface, and parameters include final milk temperature and indication of foaming value.

EFFECT: improved device and method for milk foaming are proposed.

20 cl, 19 dwg, 1 tbl

Description

Field of technology to which the invention relates

The present invention relates to milk frothing, and more specifically to methods and apparatus for frothing milk in an espresso coffee machine having a steam probe.

State of the art

Any discussion of prior art in this specification should in no way be construed as an assumption that such prior art is generally known or forms part of the general general knowledge in this field.

Steamed milk is used to make drinks such as café lattes, cappuccinos and other hot drinks. When steamed milk is prepared in a jug, steam or a mixture of steam and air is generally introduced into the milk through a probe. However, the design of the probe, which includes a temperature sensor such as a thermistor, also adapted to carry steam or a mixture of steam and air, is quite complex; however, a system incorporating such a probe will benefit from simplified design.

The steam probe has an end that can be dipped into the milk tank. The probe introduces steam or a mixture of steam and air into the milk. The final product is milk foam. Milk foam has a target temperature and foam structure. Different drinks require different milk foam structures. Structure refers to the air content and bubble size distribution of milk foam. Achieving the correct temperature and structure in the final foamed product requires either the presence of an experienced operator or the presence of a foaming device that is at least partially automated. The contents of applicant's PCT patent application as well as World Intellectual Property Organization (WIPO) publication number WO 2012/151629 are incorporated herein by reference.

Disclosure of the invention

According to an aspect of the technology, a milk frothing device is provided.

According to an aspect of the technology, a coffee preparation device and/or a milk frothing device is provided, which includes: a steam source and an air source connected to an air introduction module for mixing air and steam.

In accordance with an aspect of the technology, there is provided an espresso coffee machine including a milk frothing device, as further disclosed in this specification.

The milk frothing device may be configured by a user by receiving input parameters via user input. Parameters may include the final temperature of the milk, an indication of the type of milk, and/or an indication of the amount of foam. The milk type indication may include a representative example of milk types for the user to select. The indication of the amount of foaming may be presented in the form of a scale (eg, numbered) for selection by the user.

According to an aspect of the technology, a milk frothing device is provided, the device includes:

a steam channel to provide heated steam to heat the milk;

an air passage including an air pump;

an air introduction module to direct air from the air passage to the steam passage, thereby forming an air-steam mixture;

steam output to provide passage of the air-steam mixture to heat the milk;

a plurality of sensors including a milk temperature sensor and a steam/air pressure sensor; And

a controller in communication with a memory device storing operational parameters and foaming parameters, wherein the controller is configured to: receive operational parameters and received signals from a plurality of sensors; calculating the pressure setpoint from operating parameters and signals; and providing control signals for controlling the operation of the steam path and the air path to froth the milk according to operating parameters.

The milk frothing device may further include a user interface for receiving one or more foam parameters from user input. The foaming parameters may include the final temperature of the milk, the type of milk, and/or the amount of foaming.

The foaming parameters that characterize different types of milk may dictate different milk consistencies, and/or range of milk ingredients (eg, fat content or additive content), and/or commercial range of milk. The milk type foaming parameter allows you to search and select associated operating parameters for foaming a certain type of milk to a certain consistency.

Foaming parameters, which characterize different amounts of foaming, can indicate the selected foaming consistency. This foam quantity input parameter allows the search and selection of an associated operational parameter to froth the milk to a specific foam consistency. This foam amount input parameter can be used with the milk type input parameter to allow the search and selection of an operational parameter for foaming a specific milk type to a specific foam consistency.

The controller may be further configured to record the received pressure signal over time during the foaming process, as well as determine whether the received pressure signal exceeds a maximum pressure threshold.

The controller may be further configured to sense a control signal for the air pump in the air passage and determine whether the power of the air pump exceeds a maximum power threshold for the air pump.

The controller may be further configured to provide a signal indicating for display by the user interface a blocked steam probe, as well as a signal indicating the probable cause of a blocked steam probe based on the fact that a maximum pressure threshold, and/or a maximum pump power threshold has been exceeded.

In accordance with an aspect of the technology, there is provided an espresso coffee machine including a testing means or method for indicating whether a steam probe is blocked or not, as disclosed herein.

In accordance with an aspect of the technology, a method for frothing milk is provided, as disclosed in this specification.

The milk frothing method may include the step of receiving input parameters via user input in order to be configurable by the user. Parameters may include the final temperature of the milk, an indication of the type of milk, and/or an indication of the amount of foam. The milk type indication may include a representative example of milk types for the user to select. The indication of the amount of foaming may be presented in the form of a scale (eg, numbered) for selection by the user.

The method of foaming milk includes the following steps:

accepts user input parameters including final milk temperature, foam level and milk type;

accepts an intermediate threshold value and offsets the air pressure based on user parameters;

heating the milk to an intermediate temperature while at the same time applying bias air pressure to the air pump;

reducing the pump power or turning off the air pump and heating the milk to the final temperature.

The method may further include monitoring the air pressure in the steam probe as well as monitoring the power of the air pump. The method may further include determining whether the air pressure exceeds a maximum pressure threshold, and/or whether the power of the air pump exceeds a maximum power threshold.

The method may further include determining a probable cause of the steam probe being blocked based on exceeding a maximum air pressure threshold, and/or a maximum power threshold, and providing a corresponding indication on a user interface.

In accordance with an aspect of the technology, a machine for making espresso coffee and/or frothing milk is provided including a drip tray and/or a temperature sensor as disclosed herein.

According to an aspect of the technology, a milk frothing device is provided, the device includes:

steam source;

an air source connected to the air introduction module for mixing air and steam;

user interface for receiving input commands from the user; And

whereby the device can be configured using input parameters received through a user interface, these parameters include the final temperature of the milk and an indication of the amount of foam produced.

An indication of the amount of foaming may be provided in the user interface using a scale for user selection. The input parameter may further include a type of milk.

The device may additionally include:

Steam channel to provide heated steam to heat the milk;

An air passage including an air pump;

Air injection module to direct air from the air channel into the steam channel, resulting in an air-steam mixture;

Steam extraction to ensure the passage of the air-steam mixture to heat the milk;

Multiple sensors including milk temperature sensor and steam/air pressure sensor; And

A controller in communication with a storage device storing operational parameters and foaming parameters, wherein the controller is configured to: receive operational parameters and received signals from a plurality of sensors; calculating the pressure setpoint from operating parameters and signals; and providing control signals for controlling the operation of the steam path and the air path to froth the milk according to operating parameters.

The foam consistency input parameter can be used with the milk type input parameter to allow the search and selection of an operational parameter for frothing a specific type of milk to a specific foam consistency.

The controller may be configured to record the sensed pressure signal over time during the foaming process, as well as determine whether the sensed pressure signal exceeds a maximum pressure threshold.

The controller may be configured to sense a control signal for the air pump in the air passage, as well as determine whether the air pump power exceeds a maximum threshold value for the air pump power.

The controller may be configured to provide a signal indicating a blocked steam probe to a user interface for display, as well as a signal indicating the probable cause of a blocked steam probe based on the fact that a maximum pressure threshold, and/or a maximum pump power threshold has been exceeded.

According to an aspect of the technology, a method for frothing milk is provided, including the following steps:

reception of user parameters, including the final temperature of the milk, the amount of foaming and the type of milk;

accepting an intermediate temperature threshold and shifting the air pressure value based on user parameters;

heating the milk to an intermediate temperature while at the same time applying an air pressure bias to the air pump;

reducing the pump power or turning off the air pump and heating the milk to the final temperature.

The method may further include the step of monitoring air pressure in the steam probe as well as monitoring the power of the air pump. The method may further include the step of determining whether the air pressure exceeds a maximum pressure threshold, and/or whether the power of the air pump exceeds a maximum power threshold. The method may further include the step of determining a probable cause of blockage of the steam probe based on exceeding a maximum air pressure threshold, and/or a maximum power threshold, and providing an appropriate indication in the user interface. The method may further include the step of providing a device for frothing milk, as previously described herein.

According to the technology aspect, a milk frothing device temperature measurement assembly is provided, the assembly includes:

A temperature sensing element and an elastic support element that receives the temperature sensing element and biases it toward thermal contact with the bottom of the reservoir;

In this case, the assembly unit is located towards the end of the protruding portion, which protrudes from the body of the milk frothing device; And

The upper surface of the temperature sensor assembly is configured to facilitate the movement of liquid into the moisture collection pan reservoir.

The support may form a seal between the protruding portion and the top surface defined by the individual element.

The top surface member may have an opening such that the elastic support member forms a seal to restrict liquid penetration through the opening.

The elastic support member may be held in compression between the body extension or frame and the top surface member to create a watertight seal.

The top surface feature may be attached to the projection portion by one or more clips extending from the underside of the top surface feature that engage corresponding recesses in the projection portion.

The shoulder of the projection portion may support the elastic support member, whereby the elastic support member is captured and held in an abutting position by the projection portion and the top surface member.

The protruding portion may have an opening for receiving a temperature sensor, which is covered by an elastic support member.

The temperature sensing element may be retained within the elastic support member and the U-shaped retainer may engage both the temperature sensing member and the elastic support member. The U-shape retainer can prevent the temperature sensing member from being pulled upward and also prevent the temperature sensing member from being deflected too far downward due to engagement with the frame.

A stiffener in a milk frother may limit the downward deflection of the temperature sensing element.

The sleeve defined by the protruding portion may engage the downwardly extending outer wall of the resilient support member.

Free space below the elastic support element may allow downward movement of the elastic support element.

The temperature sensing element may be in thermal contact with the reservoir, wherein the temperature sensing element is further coupled to a processor module that receives the temperature signal and controls the steam generation module to generate steam delivered to the reservoir.

The assembly may include a milk frothing device as previously described.

Brief description of drawings

A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

fig. 1 is a schematic diagram of an embodiment of an espresso coffee machine;

fig. 2 is a schematic diagram of another embodiment of the invention of an espresso coffee machine;

fig. 3 is a flowchart for an embodiment of the invention of a milk frothing method;

fig. 4A is a graph showing a portion of the control cycles of an embodiment of the milk frothing method according to FIG. 3;

fig. 4B is a graph showing control cycles of an embodiment of the milk frothing method according to FIG. 3;

fig. 5A is a graph depicting controlled pump power and measured temperature during a milk frothing cycle, showing typical results for the device without a blocked steam probe;

fig. 5B is a graph depicting controlled pump power and measured temperature during a milk frothing cycle, showing typical results for the device with the steam probe blocked;

fig. 6A is a graph depicting measured air pressure and measured temperature during a milk frothing cycle, showing typical results for a device without a blocked steam probe;

fig. 6B is a graph depicting measured air pressure and measured temperature during a milk frothing cycle, showing typical results for a device with the steam probe blocked;

fig. 7 shows an exemplary embodiment of the invention of a drip tray having a built-in temperature sensor;

fig. 8A and 8B show an exemplary embodiment of the invention of a device having a built-in temperature sensor and a cooperating drip tray;

fig. 9A-9C show cross-sectional views of an exemplary embodiment of a device having a built-in temperature sensor and a drip tray cooperating therewith, the figures depicting the sequence of steps involved in engaging the drip tray cooperating with the device and the temperature sensor;

fig. 10 shows an embodiment of the invention of a milk frothing device;

fig. 11 shows an embodiment of the invention of a removable drip tray for the milk frother shown in FIG. 10;

fig. 12A and 12B show a milk frothing device according to FIG. 10, wherein the moisture collection pan is attached or removed;

fig. 13A to 13C show sectional views of a milk frothing device according to FIGS. 10, wherein the moisture collection pan is attached or removed;

fig. 14 shows a view of a temperature sensor assembly of a milk frothing device;

fig. 15A is a sectional view of a temperature sensor assembly of a milk frothing device;

fig. 15B shows an enlarged cutaway view of the temperature sensor assembly shown in FIG. 15A;

fig. 16 is a partial sectional view of a milk frothing device having a temperature sensor thermally connected to the jug;

fig. 17 is a schematic diagram of an embodiment of the milk frothing apparatus;

fig. 18 is a flowchart for an embodiment of the milk frothing method;

fig. 19 is a graph depicting control cycles for an embodiment of the inventive method according to FIG. 17.

Carrying out the invention

Apparatus and methods for improved milk frothing have been described in PCT patent publication PCT/AU2014/000947, published as WO/2015/042652. The contents of this patent publication WO/2015/042652 are incorporated herein by reference.

Air flow controlled milk frother

In existing automatic milk frothing systems, it is difficult to achieve high-quality frothed milk consistency and good reliability. Cleaning is an issue with the current design of the temperature sensor inside the vapor probe tip.

In an exemplary embodiment of the invention, an air stream from a precisely controlled compressed air source may be combined with a steam path to allow controlled frothing and structuring of milk. The mixture of steam and air is released through a steam probe, which can be immersed in the milk jug. The heating and frothing cycle may be affected by temperature feedback to the milk as measured by a temperature sensor (eg, at the base of the jug or at the base of the milk frother itself). The user can select or program profiles for different types of milk (i.e. non-skimmed milk, skim milk, soy milk, UHT milk, etc.). The resulting steam/air mixture is then combined with the milk in the jug via a submersible steam probe. The addition of air cycle steps is dependent on feedback from, for example, the jug temperature sensor, since, as further described later, air is added during the frothing process until the milk reaches an intermediate temperature.

In some embodiments of the invention, a cleaning cycle is selectively and/or automatically initiated. A cleansing steam pulse can be used when the steam probe returns to its original position (for example, automatically using a spring-loaded and damping mechanism). Cleaning can be automated using an offset steam probe and a cleaning steam pulse. Probe position feedback and/or previous cycle data can also be used as input to the cleaning process (i.e. cleaning may not be necessary if the milk is not heated).

In an embodiment of the invention, the milk frothing device has a steam source, a compressed air source, one or more air pressure sensors interacting with inlets on the mixing component (i.e., Venturi flow meter, jet pump or T-function component), and a control module , connected to an air pressure sensor to control the air source so that the air pressure applied to the mixing device is sufficient to provide a pressure difference. The controlled pressure difference allows for variable air flow into the steam channel.

A temperature sensor for measuring the temperature of the milk in the jug (eg, interacting with the base of the frothing jug) may be attached to the control module to allow control of steam and air sources, as further described below.

In some embodiments of the invention, the control module receives sensor signals that measure operating conditions and calculate parameters for controlling, respectively, the air source and/or the steam source. Controlled components such as the steam source and air pressure can be continuously adjusted throughout the steam cycle using a control logic loop.

It should be appreciated that an embodiment of the invention, by way of example only, may provide one or more of the following advantages:

- providing more precise control of the introduction of air into the steam channel, allowing for improved quality of milk foaming;

- providing automatic adjustment of air pump parameters to compensate for variations associated with operating conditions (i.e. steam flow, steam generator pressure, air pump pulses and probe back pressure);

- providing the ability to use different control profiles based on the type of milk (ie soy, skim, non-skim milk, etc.). This can be achieved by adjusting operational parameters that may influence the final outcome of dairy products;

- making it possible to reduce the cost of a small pump configuration compared to existing competitive systems.

Fig. 1 and 2 show an example of piping and control circuitry for illustrative embodiments of the invention.

Shown in FIG. 1, an example of an espresso coffee brewing machine 100 includes a steam generator 120, a pressure transducer 154, and a milk temperature sensor 156 (eg, using a negative temperature coefficient "NTC" sensing element) interacting with the base of the espresso coffee brewing machine 100.

This exemplary embodiment of the device 100 includes a water source 110 to provide the device with water, typically through a filter cartridge 112, which is moved by a pump 114 to the steam generator 120. The supply line 115 leading to the steam generator has a relief valve 116, and leads to an overflow a passage 117 leading to a moisture collection pan 118. The steam generator also has a vacuum breather valve 119 which is in fluid communication with the moisture collection pan.

The processor module 130 monitors the operation of the steam generator 120 through a level sensor 121 and/or a pressure sensor 122 (e.g., a piezoresistive strain gauge pressure transducer) and/or a thermal fuse 123 and/or a thermostat 124. The water tank 110 may further include itself a water level sensor 113 attached to the processor module 130 to monitor water availability.

The solenoid 140 controls the release of steam flow to the steam probe 142 through an air injection module 144 and an optional static mixer 149. The air injection module includes a primary steam flow path 145, an air injection path 146, and an exhaust flow path 147. For example, the air introduction module may include a Venturi flow meter. The air injection passage 146 may receive compressed air supplied by the air pump 150, typically through a one-way valve 152. A pressure sensor 154 is coupled to the air injection passage 146. Pressure sensor 154 provides pressure measurements for processor module 130 .

It should be appreciated that with the air pump 150 disabled (faulty), the pressure sensor can monitor the baseline pressure level provided by the air injection module under the influence of the air-steam flow and any back pressure provided by the vapor probe. With the air pump 150 activated and operating at variable power levels (0% - 100%), the pressure sensor monitors the level of pressure in the air flow injection port to allow control of the pump.

It should be additionally taken into account that with the air pump activated (power can be 0% - 100%), if the measured pressure is greater than the residual pressure measured when the air pump is switched off, then air will be introduced into the steam flow channel, then mix and apply to the steam probe.

Temperature sensor 156 monitors the temperature of the milk and provides a temperature-related signal to processor module 130 .

The processor module 130 is coupled to a user interface 160 including a display element 162 and a plurality of user input elements 164 .

In an embodiment of the invention, the descaling valve 170 may allow flow from the steam generator to be directed to the drip tray.

In some embodiments of the invention, the milk frothing device described herein optionally cooperates with or is integrated with an espresso coffee machine.

As shown in FIG. 2, an exemplary milk frothing device 200 includes a heating element transducer system 222, 223, 224, a pressure transducer 254, and a milk temperature sensor 256 (negative temperature coefficient “NTC”) in communication with the jug. Fig. 2 shows an embodiment of the invention using flow through a steam element 220 (eg, a fuser) instead of the steam generator of embodiment 100 of the invention. The temperature sensor may be removable and removed from the jug, as described in more detail below.

The milk frothing device 200 includes a water source 210 for providing water, optionally through a filter cartridge 212, wherein the water is moved by a pump 214 to the steam element 220. The supply line 215 leading to the steam element has a relief valve 216 , and leads to an overflow channel 217 leading to a moisture collection pan 218.

Processor module 230 monitors the operation of steam element 220 through a pressure sensor (e.g., a piezoresistive strain gauge pressure transducer) (not shown) and/or a temperature sensor 222 (e.g., an NTC thermistor), and/or a thermal fuse 223, and/or thermostat 224. Water tank 210 may further include a water level sensor 213 coupled to processor module 230 to monitor water availability.

Solenoid 240 controls the release of steam flow to steam probe 242 through air injection module 244 and an optional static mixer 249. The static mixer may allow additional fluid to combine with the steam, making it more uniform. The air introduction module includes a primary vapor flow passage 245, an air introduction passage 246, and an exhaust flow passage 247. For example, the air introduction module may include a Venturi flow meter. The air injection passage 246 may receive compressed air supplied by the air pump 250, typically through a one-way valve 252. A pressure sensor 254 is coupled to the air injection passage 246. Pressure sensor 254 provides pressure measurements for processor module 230.

It should be appreciated that with the air pump disabled (faulty), the pressure sensor can monitor the baseline pressure level provided by the air injection module under the influence of the air-steam flow and any back pressure provided by the steam probe. With the air pump activated (unlocked), the pressure sensor monitors the pressure level in the airflow duct.

It should be further taken into account that with the air pump activated, if the measured pressure is greater than the residual pressure measured with the air pump disabled, then air will be introduced into the steam flow path, then mixed and supplied to the steam probe.

In this exemplary embodiment of the invention, a temperature sensor 256 interacting with the jug monitors the temperature of the milk and provides a temperature-related signal to the processor module 230.

Processor module 230 is coupled to a user interface 260 including a display element 262 and a plurality of user input elements 264.

Fig. 3 shows an embodiment of the invention of a flowchart 300 performed by a processor module for providing and monitoring production of frothed milk.

At the beginning of the method 300, the user may determine the type of milk, typically by selecting from a list including a variety of known types of milk, for example, selected from a set containing whole milk, skim (low fat), soy milk, and UHT milk.

At the beginning of the method 300, the user can determine the degree of milk froth or foam volume, typically by selecting from a list including a plurality of preset values indicating the corresponding froth or foam volume, for example, being selected from a low value to a high value.

At the start of method 300, the user can determine the final temperature of the milk. Alternatively, the final milk temperature may be preconfigured and/or adjustable (or adjustable during use, or stored).

Method 300 may use the selected milk type and milk froth level/foam volume to configure the device. Table 1, as an example only, shows a matrix that is determined by the type of milk and the degree of milk froth/foam volume. The matrix can be used to search for and select parameters used in the method, as discussed below. For example, the user selected the milk type "skim milk" with a froth/foam volume of 4. This would mean that the parameters for the method are: a pressure offset of 35 units and an intermediate stage temperature of 45 °C.

The terms “intermediate stage” and “stage 2” are used interchangeably when referring to the method described herein.

Table 1

Volume of frothed milk/foam 1 2 3 4 5 6 Milk type Whole milk 40°C/0 pressure difference 40°C/5 pressure difference 40°C/15 pressure difference 40°C/35 pressure difference 40°C/60 pressure difference 40°C/100 pressure difference skimmed milk 45°C/0 pressure difference 45°C/0 pressure difference 45°C/0 pressure difference 45°C/0 pressure difference 45°C/0 pressure difference 45°C/0 pressure difference Soy milk 45°C/0 pressure difference 45°C/0 pressure difference 45°C/0 pressure difference 45°C/0 pressure difference 45°C/0 pressure difference 45°C/0 pressure difference Ultra pasteurized milk (UHT) 45°C/0 pressure difference 45°C/10 pressure difference 45°C/20 pressure difference 40°C/35 pressure difference 40°C/60 pressure difference 40°C/100 pressure difference

Fig. 3A and 3B show, by way of example only, a method 300 including any one or more of the following steps:

Step 302: Begins upon receiving user input to activate the automatic frothing cycle (at step 301) and proceeds to step 304.

Stage 1 is a preparatory stage in which the method checks that the milk has not yet reached the final temperature and, if the temperature has not yet been reached, begins heating for a short initial period without adding air.

Step 304: Steam flow to the probe is activated and the status is presented to the user display; this action begins the first stage of heating for the first period of time (for example, the initial two seconds), using only steam; the process proceeds to step 306.

Step 306: Compares the measured milk temperature with a first target or threshold temperature (e.g., 60/65 °C, which typically constitutes the final temperature), where if the measured milk temperature is less than the threshold temperature, the process proceeds to step 308, otherwise If so, the process proceeds to step 334 where the steam supply is deactivated and the foaming process is completed.

Step 308: If the no-air timer has exceeded the first predetermined period of time (eg, 2 seconds), then the process proceeds to step 310, otherwise the process proceeds to step 306; this allows the first stage to continue for the first specified period of time, assuming that the temperature threshold has not yet been reached.

Stage 2 is the foaming stage, in which air is added to the steam channel in order to add air to the milk to foam. Stage 2 ends when the intermediate temperature is reached, as shown in Table 1.

Step 310: At the beginning of step 2, the pressure setpoint is calculated; for example, requiring the air pump to be turned off, the air pressure is measured using a pressure transducer (e.g., pressure sensor 154 or 254), resulting in a baseline pressure measurement in some unit (not requiring calibration); for example, the pressure set point can be calculated by combining the base air pressure and the pressure offset in the same units based on the user's selected milk type and froth/foam volume using the table above; for example, the pressure setpoint may also add additional offset based on the rate of change in the pressure calculation, as discussed below; the process then proceeds to step 311.

Step 311: turning on the air pump (for example, 50% or higher); the process proceeds to step 312.

Step 312: If the measured milk temperature is less than the set point or user-selected intermediate stage threshold temperature (e.g., 40/45 °C), the process proceeds to step 314, otherwise the process proceeds to step 322; this allows the second stage to continue until the intermediate stage threshold temperature is reached.

Step 314: If the air pump timer exceeds a second predetermined time (e.g., 1 second), the process proceeds to step 310 (allowing the base pressure to be remeasured and then the next pressure set point calculated), otherwise the process proceeds to step 316 and controls the air pressure. pump to achieve the set pressure value.

Step 316: If the measured air pressure is less than the minimum threshold value (for example, 5 psi, pounds per square inch), then the air pump is turned off (during step 317) and the process proceeds to step 312, otherwise the process moves to step 318 This step is a safety step to ensure that the foaming device is functioning properly and that the pressure does not fall below normal operating values.

Step 318: If the measured air pressure is less than the set value, then the air pump power is increased (during step 319) and the process moves to step 320.

Step 320: If the measured air pressure is greater than the set value, then the air pump power is reduced (during step 321) and the process proceeds to step 312, otherwise the process moves to step 312.

Stage 3: The milk is further heated to a final temperature that is set by the user (or the final default temperature) without further adding foaming air.

Step 322: turning off the air pump, the process goes to step 324; The steam remains active to continue heating.

Step 324: If the milk temperature exceeds the target temperature (eg, 60/65 °C), then the process proceeds to step 326, otherwise waits at step 324 until the milk temperature exceeds the target temperature.

Step 326: Steam flow is deactivated, status is presented to the user display, and the process proceeds to step 328.

Step 328: receiving measured or calculated data related to air pressure and pump power (during step 329); enabling the determination of operating parameters to determine whether there is a limitation in the steam tip or probe that degrades the performance or consistency of the system; if a blockage is detected, the process proceeds to step 330, otherwise the process proceeds to step 332; for example, if the desired air pressure profile exceeds a predetermined maximum (block) pressure threshold, a blockage may be detected, and/or if the desired airflow power profile exceeds a predetermined maximum (block) power threshold, a blockage may be detected.

Step 330: The status presented to the user indicates that the vapor probe may be blocked, and the process proceeds to step 332. Additionally, the status information may provide details about the likely source of the vapor probe being blocked, as further described below.

Step 332: End of the automatic foaming cycle.

It should be appreciated that in this embodiment of the flowchart 300, each temperature and timer value is provided as an example only and may be adjustable and/or calculated by the processor module, and/or may have different set values. Since the process provides continuous monitoring of temperature and pressure provided by the steam probe, the user can adjust the set temperature and/or frothing settings and/or milk type at any time during the cycle. The user can also stop the loop at any point.

It should also be appreciated that during the foaming cycle, the air pressure control loop may cause the air pressure set point to increase over time using rate change calculation, which provides an estimate/prediction of the air pressure set point during the pump time cycle based on previously read values air pressure.

It should also be appreciated that steps 316, 317, 318, 319, 320, 321 operate as feedback control 315. Pressure feedback control 315 may be employed using any conventional or known feedback methods and includes, but is not limited to, On-Off Control, Proportional Control, Proportional Derivative Control, Proportional Integral Control, proportional-integral-derivative control (PID control) and third-order control systems.

During step 328, it is determined whether blockage has occurred, where the determination may include identifying whether the desired pressure profile exceeds a predetermined maximum (blockage) pressure threshold, and/or blockage may be detected if the desired pump power profile exceeds a predetermined maximum (blockage). blocking) power threshold. It should be taken into account that:

(a) if the pressure increases above the pressure threshold due to the generation of steam by the steam generator, blockage may occur, and/or

(b) If the required pump power during the second stage is equal to or approximately equal to the pump capacity (no set point is higher than the measured base pressure), blockage may occur.

By monitoring both air pump power and base pressure, if the air pump power required during the second stage is equal to or approximately equal to the pump output and the pressure is not outside the threshold, there may be an air pump failure.

Monitoring blockages and air pump status will be further discussed later.

During the air pump control process, a certain residual or base pressure exists in the steam channel due to the steam used to heat the milk. This pressure is measured using pressure sensors 154, 254. The behavior of this residual pressure (or vapor pressure) can be predicted by measuring the pressure at sampling time t _n (i.e. P _n ) and calculating the rate of change of pressure (i.e. ΔP/Δt or ΔP _n ) after some that time using the latest pressure values, using traditional averaging or modeling methods. This makes it possible to predict the pressure at a subsequent point in time (i.e. P' _n+1 ), for example, P' _n+1 = P _n + ΔP _n .

Measuring and characterizing the residual or base pressure is important because the air pump pressure set point (i.e. P _set ) for adding air pressure in the steam path (i.e. P _offset ) is based on the residual pressure (either measured or estimated ). In particular, P _set = P' _n+1 + P _offset . Alternatively, P _set = P _n + P _offset without using prediction.

It should be appreciated that _Pn may be further simulated or averaged to remove distortions from the measurement results.

The pressure offset value provided in the above table can be used as P _offset . In other words, frothing milk requires a little more air (“a bit more air”) in the steam channel (in addition to the pressure that already results from the steam that heats the milk). So "a little more air" is the offset value that is provided in the table.

In the above method, the air pump is turned on at a predetermined required amount to turn on the pump (for example, 50%), and each time its turn on is followed by a pressure measurement (during which the pump turns off). Pressure measurements can be taken periodically (eg every 1 or 2 seconds). Once the air pump is turned on by the set amount to ensure starting, the pump is controlled through the feedback control loop shown in the process sequence diagram to increase/decrease the pump power by 1% to achieve the set point P _set . The control circuit operates in such a way as to quickly reach the set pressure.

If the control loop detects that the pressure is too low, this may indicate a malfunction of the steam path from the steam generator to the probe, during which the air pump is not activated to improve safety. This is shown at step 316 in FIG. 3A.

Fig. 4A is an exemplary graph 400 that displays pressure measurements during a portion of the foaming cycle.

The graph 400 shows a line 410 that depicts the measured air pressure and a line 420 that depicts the control pressure setpoint versus time. This line intersects with line 430, which plots pump power versus time.

It should be appreciated that line 420 in this example is linear and fragmented or step-continuous to provide a given controlled pressure.

In this example, the air pump is periodically turned off (eg, for tx seconds during step 412, where tx is in the range between 0.5 and 3 seconds) to allow the pressure transducer to measure the base pressure. After the base pressure is measured, an offset is set to provide the control pressure target for the sampling time period (at 422), allowing the control loop to control the air pump to provide a pressure measured at the pressure transducer that is approximately equal to the control pressure target.

From graph 400 it can be seen that the base pressure varies over time due to, for example, back pressure provided by the milk during the process, steam generator pressure and any blockages in the steam probe. By periodically monitoring the back pressure and reapplying and/or calculating the appropriate bias pressure, the air pump can be controlled to counteract any back pressure fluctuations and thus provide a more reliable mixing ratio between the steam stream and the air stream. It will be appreciated that plot 400 depicts a stepwise approximation to a control pressure target value, which may vary in accordance with a linear prediction.

In an alternative embodiment of the invention, by way of example only, the pressure control set point may also vary over time during (or within) a sampling period by simulating or predicting the base pressure during that sampling period (based on past samplings) . It should be appreciated that interpolation (eg, during step 424) may be performed based on past samples (eg, during step 426). Any suitable modeling/interpolation technology may be used.

By monitoring changes in pressure, the inlet airflow can be adjusted for individual milk type and froth amount settings, and can also allow detection of blockages in the steam probe or flow path. The operation of the vapor probe may be substantially automatic or semi-automatic.

Fig. 4B shows another example of the foaming process, this time from start to finish.

The steam generator pressure 451 is a measure of the pressure that is present in the steam channel (used to heat the milk). It should be taken into account that fluctuations in steam generator pressure over time can affect the pressure in the steam flow path, and therefore the control of steam probe pressure and steam output.

The air pressure 452 is the measured pressure in the flow path to the steam foam probe. The pressure control signal 453 is a selective air pressure setpoint for controlling the pressure in the air flow passage. This sampled air pressure, along with the offset, is used to determine or calculate the control target pressure 454. In general, the measured back pressure increases over time as air is added and/or milk is heated.

Pump power 455 is a control signal for the air pump and is indicative of pump power.

The two signals that are monitored to detect steam probe blockages are the air pressure 452 and pump power 455 signals.

The milk temperature 460 begins at ambient temperature 461 and is heated until the final temperature 462 is reached when the frothing process is complete. It will be appreciated that when the temperature of the milk reaches an intermediate value (during step 463), the process continues and moves to the next step.

Lock detection

Fig. 5A and 5B show graphs of pump power and temperature as a function of time. In accordance with the method 300 described with reference to FIGS. 3A and 3B, the pump is controlled during the second stage of the milk frothing process, which ends when the temperature of the milk reaches an intermediate value (for example, 45 °C). Please note that this graph is only indicative of expected measurements as a function of time.

Fig. 5A shows a graph 500 that includes indicative values of pump power and temperature versus time during the period of operation of the device, in accordance with the milk frothing method disclosed herein (eg, method 300).

In this example, pump power 510 is varied in accordance with the air pressure control loop described during step 2 of method 300. Air pump power is varied over time to maintain a pressure setpoint actively set by the method. Control continues to adjust the set point and control pump power until the temperature 520 reaches an intermediate target temperature (eg, 45°C) during step 522, at which point the pump is turned off. In this example, the air pump power does not reach 100% or whatever the 530 rated maximum power expected for the milk frothing process.

When determining the maximum power, the amount of the specified limit time or time exceeding this value can be calculated based on the pump running time and then compared with the threshold value. In this example, the pump power does not reach the specified threshold and the pump appears to be operating normally.

Fig. 5B shows a graph 550 that includes indicative values of pump power and temperature versus time during the period of operation of the device, in accordance with the milk frothing method disclosed herein (eg, method 300).

The control method continues to adjust the set point and control pump power 510 until the temperature 570 reaches an intermediate target temperature (eg, 45°C) during step 572, at which point the pump is turned off.

In this example, the pump power 560 is controlled in accordance with the method that is required for the pump power to reach the maximum power value 580 for a greater period of time than the time threshold during step 562. It should be appreciated that this may be an indicator that the pump is not operating correctly, or at full capacity, or the nozzle is blocked, causing the measured pressure to increase, and thus requiring an increased pressure set point, according to the method.

When determining whether or not a pump has reached a maximum threshold value, and/or has exceeded that maximum threshold value for a given time, it is possible to record (typically using time sampling) the times when the pump meets or exceeds a given threshold value, thereby calculating the length of time the pump operates above expected parameters. Alternatively, the time-weighted average can be calculated such that if the time-weighted average exceeds a predetermined threshold value, then the pump is assumed to have operated outside of expected parameters.

Fig. 6A and 6B show measured baseline air pressure and temperature as a function of time (eg, when measured by pressure transducer 154 and temperature sensor 156 in FIG. 1).

In these examples, and in accordance with method 300, it will be appreciated that the device is operated until the temperature of the milk reaches a final target temperature (eg, 65°C), by which air pressure and temperature can be monitored.

Fig. 6A shows a graph 600 depicting air pressure 610 and temperature 620 versus time, by way of example only, in which the pressure is adjusted in accordance with the pressure calculation (see step 310 in FIG. 3A) until the temperature of the milk reaches an intermediate temperature value (e.g., 45°C), in which case the baseline pressure may continue to be monitored until the process terminates when the milk reaches a final temperature (e.g., 65°C) during step 622.

In this example, the air pressure is monitored and recorded to show that the air pressure does not exceed the maximum expected operating pressure 630, or at any time point, or time-weighted average. Please note that pressure measurements are sized according to whatever transducer and A/D converter is used to make the measurement (however, the units are the same as displacement measurements as shown in Table 1 used for calculating the target setpoint). Accordingly, the maximum expected operating pressure is a value in accordance with the expected measurement range determined by the associated transmitter and analog-to-digital conversion circuitry.

Fig. 6A shows pressure fluctuations but continues to be subject to the maximum expected operating pressure 630. Accordingly, it is expected that when the pressure is maintained at the maximum expected operating pressure, the steam probe will not become blocked.

Fig. 6B shows a plot 650 of air pressure 660 and temperature 670 versus time, which is indicative of a blocked vapor probe.

The control method continues to adjust the set point and control pump power 510 until the temperature 670 reaches an intermediate target temperature (e.g., 45°C) during step 672.

In this example, air pressure 660 continues to be monitored and recorded so that it does not exceed the maximum expected operating pressure during step 662.

Obviously, with a blocked steam probe or nozzle, the pressure can continue to increase due to the pressure provided by the steam generator or steam generating unit. The measured pressure can be recorded (usually using time sampling) to record the duration of time when the measured air pressure exceeds the maximum expected operating pressure 680 (usually predetermined). Alternatively, a time-weighted average of the air pressure measurements may be used, such that if the time-weighted average exceeds the maximum expected operating pressure, then the device is assumed to be overpressurized for a specified time or average.

If the measured air pressure does not exceed the threshold value, but the pump power does, then it can be concluded that there is no blockage in the steam probe, but the pump may not be operating correctly (for example, if the pump has deteriorated due to aging or requires maintenance).

On the other hand, if both parameters, i.e. pump power and pressure exceed their respective threshold values, then it can be concluded that the steam probe is blocked. In this case, the user interface may display instructions for the user to clean the probe.

Temperature sensor and interaction with the moisture collection pan

Fig. 7 shows an exemplary embodiment of a moisture collection pan 700 having a built-in temperature sensor.

In this exemplary embodiment of the invention, the drip tray provides a support surface 710 for placing a jug upon during the milk frothing operation. The temperature sensing assembly 720 is associated with an expanded configuration whereby a temperature sensing surface 721 extends through (and above) the support surface 710 to allow the sensor to contact and thermally couple with the supported jug. Placing the jug on the temperature sensor causes the sensor to be lowered and compressed, thus maintaining a thermal connection.

In this embodiment, the temperature measurement assembly 720 includes a negative temperature coefficient (NTC) sensor 722 that is electrically coupled to the female connector portion 723. The moisture collection pan defines a reservoir portion 712 around the temperature measurement assembly 720 . The temperature measurement assembly 720 has a frame 724 that is slidably engaged through the tank bottom 714 and is biased by a compression spring 725 into a protruding configuration. An O-ring 726 and a flexible cover 727 are provided to seal the temperature sensing assembly 720 from the reservoir 712. The temperature sensing assembly 720 may include a support surface 728 that engages a drip tray support surface 710 to limit the height of the temperature sensing surface 721 , when it is in a protruding configuration. The support surface 710 is typically provided in the form of a perforated platform that can be removed for cleaning. It should be appreciated that the moisture collection pan provides a reservoir 712 around the temperature measurement assembly 720 .

It should be taken into account that an embodiment of the invention of the device for preparing coffee and/or for frothing milk can be connected with the possibility of subsequent removal to a drip tray, which makes it possible to discharge water/steam that penetrates into the drip tray. When a drip tray is attached to a device that requires the discharge of water that permeates from the device onto the drip pan, the drip pan may be further configured with a separate inlet typically interacting with or located around the connection.

By way of example only, a coffee brewing apparatus or a milk frothing apparatus may have a steam/waste water passage that fluidly connects the drip tray to an inlet (not shown). This fluid flow connection can be made with or without an electrical connection for the temperature sensor. A one-way valve may be provided to limit splashing of water held in the drip pan when the drip pan is removed from the apparatus. The one-way valve can open automatically when the drip tray is attached to the device, and automatically close when the drip tray is removed or separated from the device. This connection may be provided with a liquid seal (eg, using an O-ring or other sealing means).

By way of example only, an embodiment of the moisture collection pan may include a connection member having an inlet passage for receiving discharged water/steam and an electrical connection for receiving and transmitting a temperature signal from a temperature sensor.

Fig. 8A and 8B show an alternative embodiment of a device 800 that includes a drip pan 810 operative with a temperature sensing device 820.

It should be appreciated that the primary components of the temperature measuring device 820 may substantially correspond to the components of the temperature measuring device 720 as shown in FIG. 7.

In this example, the temperature measuring device 820 is attached to the body of the milk frother or espresso coffee machine, and is separated from the moisture collection tray 810. By way of example only, the temperature measuring device 820 may be attached to the bottom of a recess defined to receive the moisture collection tray. tray 810, and/or may be attached to the side of a recess defined to receive the moisture collection tray 810.

During use, the drip pan 810 may be moved by sliding into a recess of a milk frother or espresso coffee machine, in which a portion 812 of the upper surface of the drip tray slides over the temperature sensing device 820, with the device exiting through the opening 814.

It should be appreciated that the temperature sensing device 820 may be configured in an extended configuration in which the temperature sensor extends above the top surface of the drip tray 816.

Sliding of the drip tray 810 may be further assisted by initially pressing downwardly on the temperature measuring device against an upward bias (either manually or by application of a support surface defined by the drip pan), causing it to move beneath the upper portion 812 of the drip tray 810. Alternatively, the drip pan 810 may be lowered from an upper position over the temperature measuring device 820 such that it is received through the opening 814.

Fig. 9A-9C show a cross-sectional view of an embodiment of a device 800 that includes a drip pan 810 operative with a temperature sensing device 820.

In this example, the drip pan 810 is slidably moved into position away from the front of the milk frother or espresso machine (as best shown in FIG. 9A), such that the upper drip pan portion 812 slides over the temperature sensing device 820. causing it to lower against the upward biasing force as it contacts the support surface 813 (as best shown in FIG. 9B), until the device reaches the hole 814 and is again installed in the upper configuration through the hole (as best shown in Fig. 9C).

Temperature Sensor Assembly

Fig. 10-15 show an embodiment of a milk frothing device 1000 having a removable drip tray 1010 and/or a temperature sensor assembly 1020.

The temperature sensor assembly 1020 is positioned toward the end of the protruding portion 1021 that extends from the body of the device 1001. The temperature sensor assembly 1020 includes a temperature sensor element 1022 that moves upward to engage the underside of the jug (for example, as shown in Fig. 16).

Fig. 11 shows an embodiment of the invention of a removable moisture collection tray 1010 for the milk frothing device 1000. The drip pan 1010 has a reservoir 1011. The drip tray 1010 has a raised front lip 1012 such that when it is inserted into engagement with the body of the device 1001, a temperature sensor can pass through it and enter the hole 1013. In this embodiment, the hole 1013 extends upward from the raised collar to provide clearance for the temperature sensor when it is in the offset raised position. In an alternative embodiment of the invention, the drip pan may have a raised front collar 1012 such that when it is inserted to engage the body of the device 1001, the collar directs the temperature sensor downward (against its bias voltage) and into the hole 1013 that accommodates temperature sensor assembly 1020. To support the jug during use, a grid 1014 is formed as the upper surface of the moisture collection tray. The through passage 1015 is in fluid communication with the reservoir 1011 and cooperates with the body of the device 1001 to receive the overflowing liquid.

Fig. 12A and 12B show a milk frothing device 1000 in which the moisture collection pan 1010 is attached or detached from the device body 1001. It will be appreciated that the temperature sensor assembly 1020 is received by the moisture collection pan 1010, resulting in the top surface 1023 of the sensor assembly 1020 temperature substantially covers the hole 1013 in the upper surface of the moisture collection pan.

Fig. 13A - 13C further show sectional views of the milk frothing device 1000 in which the moisture collection pan 1010 is attached or detached from the device body.

Fig. 14 shows a line drawing view of a temperature sensor assembly 1020 for a milk frothing device.

The temperature sensor assembly 1020 includes a temperature sensor element 1022 and a resilient support element 1024 that receives the temperature sensor element 1022 and biases it toward a thermal connection with the underside of the vessel or jug used for structuring.

The support member may also form a seal between the protruding portion 1021 and the discrete top surface member 1023. It will be appreciated that the protruding portion 1021 has an opening 1026 for receiving a temperature sensor, which is covered by an elastic support member 1024. A top surface member 1023 having an opening 1027 is then positioned over the resilient support member 1024 to form a seal to restrict liquid penetration. through hole 1027 (or 1026). The top surface member 1023 is deflected toward the edge to help direct liquid into the sump assembly and may have an overhanging sump edge 1025 to further direct liquid into the sump reservoir. The top surface of the temperature sensor assembly 1020 is convex to facilitate movement of liquid or liquid into the sump tank.

The resilient support member 1024 is held in a compressed state between the body or frame extension portion 1021 and the top surface member 1023 to create a watertight seal. The top surface member 1023 is securely attached to the projecting portion 1021 of the housing or frame. For example, the top surface member 1023 may be securely attached to the body or frame extension 1021 by one or more clamping clips 1030 extending from the underside that engage cooperating recesses 1032 in the extension.

The temperature sensor element 1022 is held within the resilient support element 1024 through a small stable fixture and a U-shaped clamp 1028 that engages both elements and which prevents the temperature sensor element 1022 from being removed. The U-shaped clamp prevents the temperature sensor element 1022 from being pulled upward and prevents the temperature sensor element 1022 from being pulled down too far by engaging the frame. For example, a rib 1029 on the frame may prevent the temperature sensor element 1022 from being deflected excessively downwards.

Fig. 15A shows a sectional view of a temperature sensor assembly for a milk frothing device. Fig. 15B shows an enlarged cross-sectional view of a temperature sensor assembly.

It should be taken into account that in accordance with FIG. 15B, the shoulder 1041 of the projection portion 1021 supports the elastic support member 1024, so that the elastic support member is grasped and supported by the shoulder around the holes of the projection portion 1021 and the top surface member 1023; a sleeve 1042 defined by the protruding portion 1021 engages from below the protruding outer wall 1043 of the elastic support member 1024; free space 1045 below the elastic support element allows sufficient downward movement of the elastic support element.

Fig. 16 shows a partial cross-sectional view of a milk frothing device having a temperature sensor element 1021 thermally coupled to a vessel or jug 1050 (at a location designated 1051). A temperature sensor element 1021 is further coupled to a processor module 1060 that receives a temperature signal. The processor module controls the steam generation module 1070, which generates steam delivered to the steam probe 1080 positioned in the vessel or jug 1050. The processor module may perform a method of frothing milk.

Steam algorithm

Fig. 17 is a schematic diagram of an embodiment of the milk frothing device 1100.

For example, device 1100 includes a control module or processor module 1110, a low thermal mass heating module 1120, a water pump 1130 coupled to a reservoir 1135 to supply water to the heating module and to provide a steam source, a low volume variable air pump 1140 for creating an air source, and an ejector module 1150 (eg, Venturi/T-junction), which allows the combination of a steam source 1151 and an air source 1152.

Fig. 18 is a flowchart for an embodiment of a milk frothing method 1200 using a multi-phase structuring cycle. The method is performed using a device. For example, the method may be performed by device 1100, as shown in FIG. 15, or other device disclosed in this specification.

By way of example only, method 1200 comprises the following steps:

Step 1210: “Phase 1” includes initializing steam generation.

Phase 1 usually operates with a fixed duration. Heating modules can operate at full or high power (eg 1500 W). The water pump is started after the heater reaches a temperature of 110°C (eg measured by a temperature sensor) to ensure that steam is created and injected into the steam flow channel. For example, this phase may last for 5 seconds, and after 5 seconds the heater operates at a reduced power (for example, 900 W). An air pump is not required at this stage.

Step 1220: “Phase 2” includes introducing air.

During Phase 2, the heater is operated at low power (eg 900 W) and the steam pressure is kept low (eg approximately 0.8-0.9 Bar). This allows for the cost-effectiveness of the air pump used to supply air to the air injection module. The duration of Phase 2 is based on the user-selected foam level.

Step 1230: "Phase 3" involves stirring the steam at high power

The heater operates during phase 3 at a given power setting, which, for example, may be the same power level as during phase 2, or higher than that used during phase 2, or the maximum power setting. During this phase the air pump does not operate. The low thermal mass heater allows for a rapid increase in temperature and steam pressure to the desired level, while achieving the highest back pressure (eg 2 Bar). This high pressure steam mixes the milk and air bubbles that were introduced during phase 2. The duration of phase 3 may be temperature dependent and based on the user selected milk temperature, or otherwise configurable by the user. When the milk reaches the selected milk temperature, the method moves to phase 4.

Stage 1240: "Phase 4" soft stop

When the milk temperature reaches the desired value (for example, the user selects 65°C with an offset of 10°C), Phase 4 starts (for example, at 55°C). The hydraulic steam line maintains the steam pressure, if the steam supply is suddenly turned off, the pressure will be released into the frothed milk, creating unwanted bubbles. Reducing the heater temperature may help reduce the extent of this bubble buildup. The power decreases from 1500 W to 900 W and then to 300 W after a fixed duration of 5 seconds.

Step 1250: "Phase 5" steam line cleaning

While the heater is not powered, the water pump pulses (for example, on 4 times for 0.5 seconds and off for 0.5 seconds). This can further reduce the heater temperature to 60°C, which is best suited to prevent scale deposits from water.

By way of example only, foam level settings can be assigned with the following duration for phase 2.

Foam Level Settings Duration of phase 2 1 5 sec 2 8 sec 3 12 sec 4 15 sec 5 20 sec 6 25 sec

A pressure transducer (eg, indicated at 1153 in FIG. 17) may be used to control or maintain an appropriate pressure during phase 2 (step 1220). Due to manufacturing tolerances, system dimensions may vary. For example, if the steam tip opening is slightly larger or smaller, this will cause the back pressure to decrease or increase accordingly. The pressure transducer can sense the back pressure of the steam and accordingly will be used in controlling the power of the air pump so that the volume of air introduced is at the desired or controlled level(s).

A pressure transducer (eg, indicated at 1153 in FIG. 17) can be used to monitor pressure and detect blockages. While the heating module is operating at high or full power during stage 3, the temperature and steam pressure may be high or at maximum levels. In cases such as: blocked steam probe, blocked solenoid valve, broken steam tube, the pressure transmitter can be used to quickly detect a sudden increase in pressure or decrease in pressure, and allow the controller to take the appropriate action.

Step 1250 can be skipped if the vapor probe is raised (prior to step 1255 in FIG. 18).

During a multi-phase structuring cycle, the controller initiates the air injection phase (phase 2) by controlling a low power heating source ( ̴ 900 W) to reduce the steam pressure ( ̴ 0.8-0.9 Bar) in the ejector (e.g. Venturi/T -shaped branching). The air pump is controlled by the controller for a given time (determined by the duration of the phase), in accordance with the user-selected structuring level (foam volume). The pressure transducer is located downstream of the air pump and, by monitoring back pressure in real time, adjusts the power supplied to the pump (power adjustment) to maintain an optimized volume of air and structured mixture integration.

During a multi-phase structuring cycle, the controller receives a signal from a temperature sensor in thermal communication with the liquid being structured (eg milk) to determine when it reaches the desired temperature offset, determined by the user's desired temperature. When the desired temperature offset is achieved, the controller reduces the power supplied to the low thermal mass heater in increments from a high % of its maximum power until a low % of its maximum power is reached for a specified duration.

During a multi-phase structuring cycle, the controller will receive a signal indicating that the structuring cycle has completed or has been limited (end of phase 4, or 3, where there is no slow stop), and that the power supply to the heating source has been turned off, and activates the water pump to pulse water (for example, a cycle of four pulses of 0.5 seconds duration) through the heating source to the outlet.

It should be appreciated that the advantages of this method and system may include:

(a) Low thermal mass heater ensures quick transition from coffee to steam mode. After the milk frothing cycle, the heater is temporarily kept at a low temperature (60°C) to reduce the formation of scale on the heater.

(b) the ability to monitor and vary steam pressure while using a smaller air pump volume. High pressure steam ensures optimal results when mixing milk and air bubbles. The soft stop at the end of the cycle reduces the steam pressure towards the end of the milk frothing cycle to eliminate the formation of unwanted bubbles.

Fig. 19 is a graph 1300 that depicts the phases of the method 1100 when it is used to froth milk. This figure plots the steam temperature during the milk frothing cycle recorded at the heater outlet 1301 and upstream of the Venturi flow meter 1302.

The drawing shows the transitions between phases: phase 1 (at step 1310), phase 2 (at step 1320), phase 3 (at step 1330), phase 4 (at step 1340) and phase 5 (at step 1350). It should be further appreciated that an espresso coffee machine, by way of example only, may comprise a frothing device that is configured in accordance with embodiments of the invention provided herein.

It will be appreciated that the temperature sensing assembly of the milk frother may include:

A temperature sensor element 1022 and an elastic support element 1024 that receives and biases the temperature sensor element 1022 toward a thermal connection with the underside of the vessel;

Here, the assembly 1020 is positioned towards the end of the protruding portion 1021, which protrudes from the body of the milk frothing device 1001; And

The upper surface 1023 of the temperature sensor assembly is configured to facilitate the movement of liquid into the drip pan reservoir.

The support may form a seal between the protruding portion 1021 and the top surface defined by the individual member 1023.

The top surface member 1023 may have an opening 1027, wherein the resilient support member 1024 forms a seal to restrict fluid flow through the opening 1027.

The resilient support member may be held in a compressed state between the protruding portion 1021 and the top surface member 1023 to create a watertight seal.

The top surface feature 1023 may be attached to the raised portion 1021 by one or more clamping clips 1030 extending from the underside of the top surface feature that engage cooperating recesses 1032 in the raised portion.

The shoulder 1041 of the projection portion 1021 may support the elastic support member 1024, so that the elastic support member is engaged and held in an abutting position by the projection portion 1021 and the top surface member 1023.

The protruding portion 1021 may have an opening 1026 for receiving a temperature sensor, which is covered by an elastic support member 1024.

Temperature sensor element 1022 may be retained within resilient support member 1024, and U-shaped bracket 1028 engages both temperature sensor element 1022 and elastic support member 1024. U-shaped clamp 1028 may prevent upward pull on the element. 1022 temperature sensor and prevents the temperature sensor element 1022 from deflecting too much downwards due to its engagement with the frame.

The milk frother rib 1029 may limit excessive downward deflection of the temperature sensor element 1022.

The sleeve 1042, which is defined by the protruding portion 1021, can engage the downwardly extending outer wall 1043 of the elastic support element 1024.

Free space 1045 below the resilient support member may allow downward movement of the resilient support member.

The temperature sensor element 1021 may be in thermal contact with the reservoir 1050, wherein the temperature sensor element 1021 is further coupled to a processor module 1060 that receives the temperature signal and controls the steam generation module 1070 to generate steam delivered to the reservoir.

The milk frothing device may include: a steam source; an air source connected to the module for introducing air to mix air with steam; user interface for receiving input commands from the user; whereby the device can be configured by receiving input parameters through a user interface, the parameters including the final temperature of the milk and an indication of the amount of froth. The milk frothing device may further comprise any of the features described by the embodiment of the invention.

Explanation

It will be appreciated that the illustrated embodiments of the invention provide a device for frothing milk.

Although the invention has been described with reference to specific examples, those skilled in the art will appreciate that the invention may be embodied in many other forms.

Reference throughout the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, the phrases "in one embodiment of the invention" or "in an embodiment of the invention" appearing in various places throughout this description do not necessarily all refer to the same embodiment of the invention, but may. In addition, individual features, structures or characteristics may be combined in any suitable manner, as will be apparent from this description to one skilled in the art in one or more embodiments of the invention.

In the following claims and description, any of the terms includes, is made up of, or which contains is a non-limiting term intended to include at least the elements/features that are monitored, but does not exclude others . Thus, the term “comprising” when used in the claims should not be interpreted as being limiting with respect to the means or elements or steps listed hereinafter. For example, the scope of the expression "device containing A and B" should not be limited to devices consisting only of elements A and B. Any of the terms including, or which includes, or which includes, as used herein context, is also an open term, which also means that it includes at least the elements/features that accompany this term, but does not exclude others. Thus, includes synonyms and means containing.

Likewise, it should be noted that the term “coupled”, when used in claims, should not be interpreted as limited only to direct connections. Along with other derivatives, the terms “coupled” and “connected” may also be used. Please note that these terms are not intended to be used as synonyms with respect to each other. Thus, the scope of the expression "device A connects to device B" is not limited to devices or systems in which the output signal from device A is directly connected to the input of device B. This means that there is a path between the output of device A and the input of device B, and this the path may include other devices or means. The term “coupled” can mean that two or more elements are either in direct physical connection, or that two or more elements are not in direct contact with each other but still interact or influence each other.

In the context used here, unless otherwise specified, the use of the simple numerals "first", "second", "third", etc. to describe a general object, only shows that various examples of similar objects refer to something, and they are not intended to infer from them that the objects so described must be given in sequence, either temporally or spatially , or with ranking, or in any other way.

As used herein, unless otherwise specified, the use of the terms "horizontal", "vertical", "left", "right", "up", "down", as well as their adjective and adverb derivatives (e.g., "horizontal", "right", "up", etc.) simply refer to the orientation of the illustrated structure in which an individual drawing figure faces the reader, or reference is made to the orientation of the structure during nominal use as appropriate . Likewise, the terms “inwardly” and “outwardly” generally refer to the orientation of a surface relative to the longitudinal axis or rotation axis as appropriate.

Likewise, it should be appreciated that in the above description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure of the invention, as well as to assist in understanding one or more different inventive inventions. aspects. However, this manner of disclosure should not be interpreted as reflective of the invention because the claimed invention requires more features than those briefly cited in each claim. Moreover, as the following claims reflect, inventive aspects are not found in all features of a single embodiment of the invention disclosed hereinafter. Thus, the claims that follow the Detailed Description are incorporated into this Detailed Description, with each claim to be considered as a separate embodiment of the present invention.

In addition, while some embodiments of the invention described herein include some, but not other, features included in other embodiments of the invention, it is intended that combinations of features of various embodiments of the invention should be within the scope of the invention, as will be appreciated by those skilled in the art. in this field of technology. For example, in the following claims, any of the claimed embodiments of the invention may be used in any configuration.

In addition, some of the embodiments of the invention are disclosed herein as a method or combination of method elements that can be implemented by a computer system processor or other means of performing a function. Thus, a processor with the necessary instructions for executing such a method or method element forms means for executing the method or method element. In addition, an element of an embodiment of the device described herein is an example of a means for performing a function performed by the element for the purpose of carrying out the invention.

Numerous specific details are set forth in the description provided herein. However, it should be understood that embodiments of the present invention may be practiced without these specific details. In other examples, well-known methods, structures and technologies have not been shown in detail so as not to obscure the understanding of this description.

Thus, while it is believed that preferred embodiments of the present invention have been described, those skilled in the art will appreciate that other additional modifications may be made without departing from the spirit of the invention, and all such modifications are intended to be claimed. and modifications that fall within the scope of the invention. For example, any formulas given above are only representative of procedures that may be used. Functionality can be added or removed from block diagrams, and operations on function blocks can be interchanged. Steps may be added to or removed from the methods described within the scope of the present invention.

It should be appreciated that an embodiment of the invention may consist substantially of the features disclosed herein. Alternatively, an embodiment of the invention may consist of the features disclosed herein. Illustratively, the invention disclosed herein may be suitably practiced in the absence of any element not specifically disclosed in this specification.

Claims (40)

1. A method for frothing milk, implemented by a milk frothing device, containing a step in which: receiving one or more user inputs including a desired final milk temperature; determining a temperature offset to which the milk is desired to be heated based on said one or more user input parameters; heating the milk to a certain temperature offset using steam generated by the heater; And lowering at least one of a power level or a temperature of the heater, in the process of implementing a soft stop step, once the temperature of the milk reaches a certain temperature offset. 2. The method of claim 1, wherein the heater is a low heat capacity heater. 3. The method according to claim 1 or 2, further comprising the step of: heat the heater for a specified time to generate steam from the water tank. 4. The method according to claim 3, further comprising the step of: introducing and mixing air with steam over a period of time determined based on at least one user input parameter. 5. The method of claim 4, wherein the air pump is operable to introduce and mix air with steam. 6. The method according to claim 5, further comprising the step of: Set or increase the heater power level over a period of time to increase the temperature and steam pressure to froth the milk. 7. The method according to claim 6, further comprising the step of: stopping the operation of said air pump. 8. The method according to claim 7, further comprising the step of: gradually reduce the heater power level during the soft stop phase time period. 9. The method of claim 8, wherein the heater power level is gradually decreased from the first power level to the second power level and to the third power level during the time period of the soft stop step. 10. The method of claim 9, wherein the first level is 1500 W, the second level is 900 W, the third level is 300 W, and the time period is 5 seconds. 11. Method according to any one of paragraphs. 1-10, wherein said one or more user input parameters further include a frothing amount and a milk type. 12. The method according to claim 11, in which the temperature shift is 10 °C less than the final temperature of the milk. 13. A method of operating a coffee making machine containing a milk frothing device, comprising the steps of: receiving user input parameters including a final milk temperature and a frothing amount; determining a temperature offset to which the milk is desired to be heated based on the specified user input parameters; heating the milk to a certain temperature offset using steam generated by the heater; lowering at least one of the power level or temperature of the heater, in the process of implementing a soft stop step, as soon as the temperature of the milk reaches a certain temperature offset; And wash the steam channel of the device by supplying, in pulse mode, water through the steam channel. 14. Milk frothing device containing: heater; And controller configured to: receiving user input parameters including final milk temperature and foaming amount; determining a temperature offset to which the milk is required to be heated based on specified user input parameters; controlling a heater to generate steam to heat the milk to a specified temperature offset; lowering at least one of the power level or temperature of the heater, in the process of implementing a soft stop step, once the temperature of the milk reaches a certain temperature offset. 15. The milk frothing device according to claim 14, wherein the heater is a low heat capacity heater. 16. The milk frothing device according to claim 14 or 15, in which the controller is additionally configured to: heat the heater for a predetermined time to generate heated steam from the water tank. 17. The milk frothing device according to claim 16, wherein the controller is further configured to provide an air pump for introducing and mixing air with steam. 18. The milk frothing device of claim 17, wherein the controller is further configured to set or increase the power level of the heater over a period of time to increase the temperature and steam pressure for frothing the milk. 19. The milk frothing device according to claim 18, wherein the controller is further configured to gradually decrease the power level of the heater during the time period of the soft stop step. 20. The milk frothing device according to claim 19, wherein the power level of the heater is gradually decreased from the first power level to the second power level and to the third power level during the time period of the soft stop step.