Untitled record

COFFEE MACHINE USING A HEAT PUMP AND MEANS FOR CONTROLLING THE SUPPLY TIME OF A HEATING ELEMENT OF A BOILER

Technical area

The present invention relates to the field of coffee machines of the filter coffee type.

The object of the present invention is more particularly to design a coffee machine of the filter coffee type comprising means for producing from the same filter holder and the same stop-drop:

(a) small amounts of coffee directly into a small cup, bowl or mug container,

or (b) large quantities of coffee in a large jug-type container.

By small container in the sense of the present invention is meant here a container such as for example a cup, a bowl or a mug that is able to contain a volume of coffee for individual consumption.

The small container opposes the large container which is intended for collective consumption and which is in the form of for example a jug.

It is understood here that small containers such as large containers are food containers sized to be positioned under the filter holder and able to withstand high temperatures.

State of the art

In the state of the art, coffee machines of the filter coffee type are known comprising means for detecting the presence or absence of a container under the filter holder in order to determine the quantity of coffee to be prepared.

Document NL1000322 thus discloses a coffee maker comprising a filter holder provided with a stop-drop constituted by a metal ball.

In this document, the coffee maker has an automatic stop-drop control device comprising an optical detector for the presence of a jug which is configured to manage the stop-drop position: when a carafe is detected, the stop-drop is in the open position otherwise it remains in the closed position. The automatic control device proposed in this document includes an electromagnet for moving the ball according to the information provided by the presence detector.

The document US7231870 discloses another solution with a coffee maker also having a filter holder provided with a stop-drop.

There is also in this document an automatic stop-drop control device comprising a jug presence detector configured to manage two stop-drop positions: an open position when a carafe is detected and a closed position otherwise.

The automatic control device proposed in this document comprises an electromagnet which cooperates with a magnetic part of the stop-drop. It is then provided means for driving the electromagnet and allow opening and / or closing of the stop-drop according to different scenarios programmed according to the type of container detected under the filter holder.

In "mug" cycle for example: the tank is filled with a cup. The stopgoutte is in the closed position and the water heater is started for a predetermined time corresponding to a given size of mug.

It will be noted here that the predetermined heating time can be modified by the user.

It is therefore provided in this document to determine the amount of coffee to prepare for the mug according to a predetermined heating time. When all the water has been heated, a temperature sensor in the boiler detects the increase in temperature and opens the stop-drip for a pre-programmed time that can be variable depending on the heating time.

The Applicant observes, however, that in this document, it is expected the implementation of an electric pump to heat the water in the tank.

This electric pump that is coupled to the boiler is configured to push the water into the boiler at a predetermined flow rate that allows the water that comes out to be hot.

Such an electric pump is expensive and complex to implement. It requires replacing boilers conventionally used on traditional coffee machines.

Summary of the invention

The present invention aims to improve the situation described here.

One of the objectives of the present invention is to overcome the various disadvantages mentioned above by providing a coffee machine that has a simple design and is economical to implement, especially to achieve different volumes of coffee.

For this purpose, the object of the present invention relates to a coffee machine comprising:

- a water tank,

a boiler comprising a water tube and a heating element configured to heat the water circulating in the tube,

a filter holder intended to receive, in particular, ground coffee, the machine being characterized in that it further comprises:

a non-return valve arranged between said water tank and said water tube for the implementation of a heat pump ensuring a flow of hot water from said tube to said filter holder,

control means configured to electronically control the power supply of the heating element, said control means implementing a management algorithm configured to trigger the power supply of said heating element during a heating period determined so as to provide said filter holder a volume of hot water corresponding to a predetermined proportion of a capacity of a container positioned under the filter holder to receive the coffee.

Once the control means activated, it then becomes possible to provide the filter holder with a volume of hot water corresponding to a predetermined proportion of the capacity of the container positioned under the filter holder to receive the coffee.

Advantageously, the proportion of the capacity of the container is between 60% and 95%, preferably equal to 80%. Thus, once the coffee has passed into the container, it is not completely filled with coffee and can therefore be handled easily, without risk of spilling coffee.

Advantageously, the coffee machine comprises at least one function key connected to the control circuit characterizing a type of container, including its capacity, the activation by the user of the at least one function key determining the heating period corresponding to the type of container. Electronically controlling the power supply time of the heating element allows precise control of the volume of hot water discharged into the filter holder.

The present invention thus makes it possible to pass on the same machine coffee for individual use directly in a cup, a mug or a bowl without using a carafe.

Of course, it will be understood here that the object of the present invention retains the use of the jug for non-individual uses.

Advantageously, the filter holder has a shutter valve movable between an open position in which the brewed coffee can flow into the container and a closed position in which the brewed coffee is retained in the filter holder.

Such a shutter valve therefore allows the flow of coffee brewed into the carafe in the open position (passage opening of the free filter holder) and allows the brewing of coffee in the filter holder when the door opening orifice -filter is closed by the valve.

Preferably, the filter holder comprises means for closing and opening the valve ensuring the passage from the open position to the closed position, and vice versa.

In an alternative embodiment, the closing and opening means of the valve are able to be controlled manually by the user.

Manually actuable means may be provided for this purpose to allow the opening or closing of the valve. The user can then himself manage the infusion time of his coffee to control the taste and intensity.

In an alternative embodiment, the control means are configured to electronically control the closing and opening means so that the opening of the valve is performed after an infusion period correlated with the heating period of the heating element.

In this case, it is called automatic opening and closing of the valve. This feature allows you to have programmed preparation modes.

Preferably, an embodiment is provided in which the closing and opening means of the valve comprise an electromagnet.

Alternatively, one can provide an engine or any other means for the automatic opening and closing of the valve.

Advantageously, the coffee machine according to the present invention comprises a presence detection sensor; this sensor is configured to detect the presence of a carafe under the filter holder.

Alternatively, it can be provided that the sensor is configured to detect the presence of a mug, a cup or a bowl under the filter holder.

In an advantageous embodiment, the presence detection sensor comprises an electric contactor.

Preferably, the contactor is able to transmit a detection signal to the control means in case of detection of the presence of a carafe under the filter holder.

Advantageously, the management algorithm implemented by the control means is configured to determine, as a function of the information provided by the presence detection sensor (for example: the reception of a presence detection signal of a carafe emitted by the contactor), the heating time required for the heating element to heat the volume of water that substantially corresponds to the capacity of the container positioned under the filter holder.

It then becomes possible to automatically manage the heating time of the heating element as a function of the container detected under the filter holder, which makes it possible to heat the volume of water required to fill the container positioned under the filter holder. .

It will be noted here that in case of scaling the heating time which is initially defined for the container is no longer correct. Indeed, if the machine (the tube) is scaled, it takes a longer heating time to heat the entire volume of water needed.

In case of scaling, there is therefore less hot water in the container at the end of the preparation cycle.

We therefore see with the solution proposed here that the user can detect more easily and early the scaling of the machine because its mug is no longer filled as desired in case of scaling.

In an advantageous embodiment, the management algorithm implemented by the control means is configured to determine the duration of infusion according to the information provided by the presence detection sensor.

This infusion time which triggers the opening of the shutter valve, for example by means of an electromagnet, is here a function of the container detected under the filter holder.

It thus becomes possible to correlate the infusion time according to the container detected under the filter holder.

In an advantageous embodiment, the control means are configured to implement a calibration phase. This calibration phase is able to determine the heating time required for the heating element to heat a specific volume of water such as for example a volume of water substantially corresponding to the capacity of the container positioned under the filter holder.

It thus becomes possible to calibrate the coffee machine so that it records the water volume of the container, for example a mug.

Once calibrated, the user can use the coffee machine and position his mug under the filter holder.

When the presence of the mug is detected, the management algorithm automatically controls the power supply of the heating element so that the heating time of the heating element heats the entire volume of water corresponding to the volume of the heating element. container according to the calibration initially performed.

An automatic (semi-automatic) calibration of the machine can be provided.

According to an advantageous variant embodiment, the boiler comprises a first temperature sensor. In this variant, provision may be made for the control means to be configured, during the calibration phase, to determine the end of the heating period when a rise in temperature above a first determined threshold is detected in the boiler.

In this variant, it is sufficient for the user during calibration of the machine to fill the water tank with a volume of water corresponding to the volume of the container, for example mug. When the tank is filled, the water in the tank passes into the tube and is heated to supply the filter holder.

When the tank empties (ie when the entire volume of water is heated), the temperature sensor detects a rise in temperature indicating that the tank is empty and that there is no more water. 'water.

The intelligence embedded in the coffee machine then deduces the heating time necessary to heat the entire volume of water of the container selected by the user. It records this heating time; the machine is then calibrated.

In the next use, the heating time corresponding to the time to heat the volume of the container will be known. The user will only have to position his mug so that it fills automatically with the right volume of coffee.

Alternatively, an embodiment can be provided with manual calibration.

According to an advantageous variant of embodiment, it can be envisaged that the control means comprise a manual control member, and that the control means are configured for, during the calibration phase, to determine the end of the heating period when the user activation of the controller is detected.

The heating period of the heating element can therefore be parameterized:

- with a factory setting,

- either automatically (or semi-automatically),

- either manually.

This period can therefore be predetermined at the factory with a predetermined heating time corresponding to a mug of conventional capacity.

Alternatively, the user can fill the water tank with the desired quantity.

Then, using a parameterizing function, the program records the time required between the start of the calibration cycle and the rise in temperature of the heating element indicating that the water tank is empty.

This time is then stored in memory for the following "mug" cycles.

The user can thus set the heating time of his mug which allows him to define the desired volume of water without being dependent on a factory setting. This also allows the user to fill his tank without worrying about a surplus volume compared to the volume of his mug: the heating cycle is cut at the end of the heating period.

According to another alternative, the user himself indicates the end of the heating cycle when the mug is filled as desired. The time is then stored in memory for the following "mug" cycles.

Advantageously, the boiler comprises a second temperature sensor. In this case, the management algorithm implemented by the control means is configured to cut off the power supply to the heating element when a rise in temperature above a second determined threshold is detected in the boiler.

This constitutes a means of securing the machine.

Preferably, the first and / or second temperature sensors comprise a negative temperature coefficient resistor of the CTN type or a thermostat.

It will be understood here that the first and second temperature sensors can be one and the same sensor.

Thus, thanks to the various structural and functional characteristics described above, the present invention makes it possible to overcome the disadvantages of the state of the art by proposing a management and control of the heating time of the heating element to heat the water. of the boiler according to the type of container positioned under the filter holder to heat a volume of water corresponding to the volume of the container.

Brief description of the figures

The features and advantages of the invention will appear on reading the following description based on figures, among which:

- Figure 1 shows a schematic perspective view of a coffee machine according to an exemplary embodiment of the present invention;

- Figure 2 shows a schematic perspective view of the closure and opening means of the valve and the presence detector present on a coffee machine according to Figure 1.

detailed description

A coffee machine implementing a heat pump and allowing the preparation of different volumes of coffee will now be described in what follows with reference to Figures 1 and 2.

The current use of coffee machines like filter coffee requires the coffee to pass into a carafe before serving it in a cup-type container, mug or bowl.

This makes several manipulations for individual use of a small amount of coffee.

In addition, in the case of a small amount of coffee, the hot water does not have time to be properly brewed with the coffee grounds; the coffee flows from the filter holder into the cup without delay, which alters the taste and intensity.

One of the objectives of the present invention is to design a coffee machine adapted to facilitate the individual use of a filter coffee machine for consumption of a small amount of coffee. By small amount of coffee is meant here an amount corresponding to the volume of a bowl, a cup or a coffee mug.

Another objective of the present invention is to be able to keep the hot water to be infused into the coffee ground before automatically pouring it into the cup, this to improve the taste and intensity.

This is made possible in the following example.

As illustrated in FIG. 1, a conventional coffee machine 100 is provided with a water tank (not shown) connected to a boiler 10 comprising a water tube 12 and a heating element 11 for heating the boiler. water circulating in the water tube 12.

In this example, the tank is positioned above the water tube 12 (for example at the same level as a filter holder 20) so as to allow a water supply of the water tube 12 which is naturally by gravity. It suffices to manage the opening of the tank from below to ensure the supply of water to the water tube 12.

The reservoir water therefore descends through a first portion of water tube 12 and arrives in a so-called heating zone corresponding to a median portion 12b of the water tube 12.

In this zone, the water circulating in the portion 12b is heated by the heating element 11.

In the example described here, this heating element 11 is a resistor which also serves to heat a plate 14 on which the carafe 30 or the mug is placed. It is therefore understood here that the median portion 12b passes in the immediate vicinity of this resistance, which ensures the heating of the water.

In this example and as illustrated in Figure 1, there is provided a non-return valve 13 between the first portion 12a of the water tube 12 and the middle portion 12b.

This non-return valve 13 is characteristic of the present invention.

Hot water boiling in the heating zone tries to leave this zone (by a physical phenomenon of pressure / temperature). However, this water can not go back to the first portion 12a of the water tube 12 because of the non-return valve 13; this hot water then naturally rises to a second portion 12c of the water tube 12 towards the filter holder 20.

The non-return valve 13 combined with the heating element 11 thus plays the function of heat pump and thus ensures a natural and unidirectional flow of the hot water to the filter holder 20.

At the end of the water tube 12, there is a spout 12d pouring hot water into the filter holder 20.

In this example, the filter holder 20 comprises the filter as such and the ground coffee. The ground coffee can then infuse into the hot water from the water tube 12.

As indicated above, one of the objectives of the present invention is to design a coffee machine facilitating the individual use of a filter coffee machine for consumption of a small amount of coffee.

The concept underlying the present invention is to adapt the water heating time according to the desired use, for example for the preparation of a complete carafe of coffee or for a simple mug (not shown). right here).

In the example described here, it then provides control means (not shown) for electronically controlling the power supply of the heating element 11.11 may be for example a microcontroller.

These control means are also characteristic of the present invention.

Indeed, it is provided according to the invention that these control means implement a management algorithm configured to trigger and control the power supply of the heating element 11 during a so-called heating period.

This heating period is programmed so as to heat a volume of hot water corresponding to 80% of the capacity of the carafe 30 or mug.

Controlling the heating time of the heating element 11 makes it possible to heat the volume of water necessary to fill the receptacle positioned under the filter holder 20.

In the example described here, the filter holder 20 has under its hole 20a for coffee passage a shutter valve 21 of the filter holder 20 which is movable between:

an open position in which the brewed coffee can flow through the orifice 20a into the container, and

- A closed position in which the orifice 20a is closed and the brewed coffee is retained in the filter holder 20.

In this example, the filter holder 20 further comprises means for closing and opening 22 of the shut-off valve 21 ensuring the passage from the open position to the closed position, and vice versa.

The use of an electromagnet 23 may be provided.

Thus, the electromagnet 23 acts as an actuator that pushes vertically on a rotating part 22a causing the opening of the shut-off valve 21.

Here, it is provided in this example that the electromagnet 23 is electronically controlled by the control means.

The Applicant has found that in the case of a small amount of coffee, the hot water does not have time to brew for a long time with the coffee grounds because usually the coffee flows directly from the filter holder 20 into the mug. without delay.

The fact of being able to electronically control the opening and closing of the shut-off valve 21 makes it possible to keep the hot water to be infused in the coffee grounds according to a programmed brewing period before pouring it into the mug. Thanks to the electronic control, it becomes possible to control the opening of the shut-off valve 21 so that it is achieved after a sufficient infusion period which is correlated to the heating period of the element. heating 11.

This example of implementation is particularly advantageous because it allows to delay the infusion to have a good coffee, even in a mug.

For a small amount of coffee, this makes it possible to have a better temperature of the coffee when it flows directly into the mug without passing through the carafe, the mug being preheated by the hotplate 14.

It is desirable to determine the nature of the container positioned under the filter holder 20 so that the control means can engage the right programs (heating time, infusion time, etc.) according to the container under the filter holder 20.

In the example described here, a presence detection sensor 24 is then provided. This sensor 24 is able to detect the presence of a carafe 30 under the filter holder 20.

In the example described here, the sensor 24 comprises a movable member 24a mounted in pivot connection with the machine 100 just below the filter holder 20. This movable member 24a is adapted to have two positions including a lowered position and a raised position. Thus, when positioning a carafe 30 under the filter holder 20, the carafe 30 pushes the movable member 24a and causes the pivoting thereof which moves from the lowered position to the raised position.

This passage from one position to the other operates an electric contactor 25 which emits a so-called detection signal indicating to the control means the presence of a carafe 30 under the filter holder 20.

It will be noted here that there is no direct mechanical interaction between the lid of the carafe 30 and the filter holder 20. It is indeed the sensor 24 which connects the two elements of the coffee machine. .

It is therefore possible in the context of the present invention to detect the presence of a carafe 30 or a mug. It is understood here that the mug is dimensioned so as not to come into contact with the sensor 24 when it is positioned under the filter holder 20. Thus, by default, when the electric switch 25 is not actuated, the means control consider that a mug is positioned under the filter holder 20.

In this example, the management algorithm implemented by the control means is configured to determine, based on the information provided by the presence detection sensor 24, the heating period required for the heating element 11 for the heating element. heating the volume of water corresponding to 80% of the capacity of the container positioned under the filter holder 20:

a first heating period determined for a jug 30, and

a second heating period determined for a mug.

It will be understood here that the machine 100 is configured to store several programs; it is therefore possible to determine several heating times for example for several possible mug capacities.

In the same way, the management algorithm implemented by the control means is thus configured to determine the brewing period to be provided according to the container under the filter holder 20. This infusion period is directly calculated in depending on the heating period.

The coffee machine can therefore include a function key or two separate keys corresponding to a mode "mug" and a mode "jug" (jug in English).

When the "jug" button is activated and a carafe 30 is detected, a "jug" cycle is started by the control means and the electromagnet opens the shut-off valve 21.

Conversely, when the "mug" key is activated and if no carafe is detected: a "mug" cycle is started by the control means and the electromagnet opens the shutter valve 21 with a programmed delay time (corresponding at the time of infusion).

In the "jug" or "mug" cycle, the control means are configured to control the opening / closing electromagnet of the valve according to various programmed scenarios.

In "mug" cycle: the tank is filled with a mug. The shut-off valve 21 is closed and the heating of the water begins. When all the water has been heated, the temperature sensor of the boiler detects the increase in temperature and opens the shut-off valve 21 for a preprogrammed time that may be variable depending on the heating time.

Thus, the coffee machine 100 according to the present invention makes it possible, from the same filter holder 20 and the same shut-off valve 21, the preparation of different volumes of coffee depending on the container positioned under the filter holder 20 .

The implementation of a heat pump combined with the on-board electronics makes it possible to manage the power supply times of the heating element 11 to supply the filter holder 20 with the volume of hot water necessary to fill a predetermined proportion of the capacity of the mug or jug ​​type container.

The on-board electronics can also manage the different cycles of preparation and calibration of the machine.

The different functionalities implemented on the machine remain simple for the user since the coffee machine 100 proposed in the context of the present invention operates from the point of view of this one as a conventional filter coffee maker whether in " jug "or in" mug "mode.

Finally, note that the solution provided here is simple and economical: it adapts to existing coffee makers and requires only a few minor design adjustments.

It should be observed that this detailed description relates to a particular embodiment of the present invention, but in no case this description is of any limiting nature; on the contrary, its purpose is to remove any imprecision or misinterpretation of the claims that follow.

It should also be observed that the reference signs in parentheses in the following claims are in no way limiting in nature; these signs are only intended to improve the intelligibility and understanding of the following claims as well as the scope of the protection sought.