RU2812833C1 - Coffee machine, closing and/or tamping system and valve device suitable for use in coffee machine - Google Patents

Abstract

FIELD: coffee machines.

SUBSTANCE: invention is related to a coffee machine, a closing and/or tamping system and valve devices suitable for use in such machines. The coffee machine contains a water tank (30), a water heater (34), a water pump (36), a coffee vessel (16) configured to receive freshly ground coffee, a water supply system having a water supply head (40) for supplying heated water to coffee container. The coffee machine includes a closing and/or tamping system for closing the coffee container and/or compacting ground coffee in the coffee container by allowing relative movement between the water supply head and the coffee container. The closing and/or tamping system contains a hydraulic actuator (42). The water outlet from the water pump is connected to the hydraulic actuator through a first fluid connection (44). The water outlet from the water pump (36) is connected to the water supply head through a second fluid connection (46) that includes a passive inline valve (48). The passive inline valve is configured to open when the pressure reaches a desired level.

EFFECT: automation of pressure control for closing and/or tamping and brewing coffee, as well as preventing steam from entering the grinder and container, thereby preserving the freshness of coffee beans.

15 cl, 19 dwg

Description

TECHNICAL FIELD

The present invention relates to coffee or espresso coffee machines and a closing and/or tamping system and valve devices suitable for use in such machines.

BACKGROUND OF THE ART

It is well known that coffee made from freshly ground beans produces better quality than pre-ground coffee. Often fresh beans are used to make espresso coffee.

There are many different types of commercially available espresso machines for use at home or in bars, restaurants and hotels. The type of machine that is suitable for a particular application, for example, depends on the volume of use and budget.

In a manual espresso machine, the user fills a coffee receptacle, known as a carafe, with ground coffee. The user must then tamp the ground coffee inside the cone with sufficient force, for example about 200 N, to create a so-called tablet. The cone is then installed into the coffee machine, usually using a bayonet connection. Next, the coffee machine forces hot water through a tablet in a cone, and the resulting coffee is dispensed through a spout, which is usually built into the cone. After brewing, the user must remove and empty the carafe, discarding the used coffee grounds.

In a bar setting, the manual process is carried out by a barista. In a home setting, manual process steps can make the user feel more involved in the coffee making process, and therefore can create a sense of fulfilling the role of a barista.

There are also manual espresso machines with a built-in grinder. The user switches the horn between the first position, in which it receives ground coffee, and the second position, in which the coffee is brewed. Tamping can be done manually or using a hand-operated lever.

In a fully automatic espresso machine, all the above steps are done automatically in the same machine. The machine contains a container for beans and a grinder for preparing ground coffee. This ground coffee is transported into the brewing chamber and compacted automatically by means of a piston, which can be driven hydraulically or by an electric motor. Hot water is then passed through the ground coffee in the brewing chamber, the coffee is brewed and poured, and the used coffee grounds are thrown out of the brewing chamber into a trash can inside the machine.

This process eliminates the manual steps required for a manual espresso machine and therefore saves time as well as providing more uniform results.

A manual espresso machine can be manufactured at a lower cost than a fully automated espresso machine since many of the transport steps do not need to be automated. However, results may be less uniform due to the user's involvement in the filling and tamping process, particularly the user's involvement in setting the volume or weight of the ground coffee, and the force and uniformity (straightness) of tamping the ground coffee into the tablet. A manual espresso machine requires less maintenance since the coffee tablet is removed after each brew by the consumer as part of the brewing process.

A fully automatic machine gives more consistent results but is more expensive. It also relieves the barista of the feeling of using a manual espresso machine. A fully automatic coffee machine also requires more maintenance (filling with coffee beans, dispensing water, removing waste water, and disposing of coffee waste in the trash can). A fully automatic coffee machine can also be more bulky.

A third type of coffee machine has been proposed that combines elements of the two types described above. This type is described in this document as a hybrid espresso machine.

For example, US 9,125,519 discloses a coffee machine with a removable cone used in a manual espresso machine, but which also includes a bean container and a coffee grinder for delivering coffee powder to the inserted cone. The horn acts as a brewing chamber, and the dispensing filter (forming a piston) is used to automatically tamp and thus compact the coffee powder in the horn before releasing pressurized hot water into the horn.

Thus, this hybrid espresso machine combines the elements of a manual espresso machine and a fully automatic espresso machine. Thus, in this type of machine, the user only needs to connect the empty horn to the machine. Grinding, dosing of ground coffee in the cone, tamping of ground coffee, supply of hot water and dispensing of coffee are then automated as in a fully automatic machine. After brewing, the user must detach the brewer and empty the coffee waste in the same way as when using a manual espresso machine.

Some examples in this document may apply to a manual, fully automatic, and/or hybrid espresso machine or coffee machine. Other examples relate more specifically to the hybrid type of coffee machine, including a removable coffee carafe or vessel that functions as a brewing chamber, a container for coffee beans, a grinder, and provision of automatic tamping.

While a hybrid coffee machine may be much less complex than a fully automatic coffee machine, the process of closing and/or tamping still adds complexity to the machine's design, particularly with a piston that must be inserted into the mounted coffee mug or container. It is also desirable to simplify the designs of both manual and fully automatic machines.

DISCLOSURE OF THE INVENTION

The invention is defined by the claims.

In the examples, in accordance with an aspect of the invention, there is provided a coffee machine comprising:

water tank;

water heater;

water pump;

a coffee vessel for receiving ground coffee;

a water supply system having a water supply head for supplying heated water to the coffee vessel; And

a closing and/or tamping system for closing the coffee container and/or compacting ground coffee in the coffee container by allowing relative movement between the water supply head and the coffee container;

wherein:

the closing and/or tamping system contains a hydraulic actuator;

a water outlet from the water pump is connected to the hydraulic drive through a first fluid connection; And

a water outlet from the water pump is connected to the water supply head through a second fluid connection that includes a passive integral valve, the passive integral valve being configured to open when the pressure reaches a desired pressure, such as a closing pressure or a tamping pressure.

This coffee machine uses a water pump to both supply water (for brewing) and to apply pressure during the closing and/or tamping process. This reduces the number of components and therefore reduces costs. This can also reduce the size of the machine.

A passive inline valve is a valve that opens only when the desired pressure is reached. It remains closed until the desired pressure is reached. The desired pressure can be selected, for example, so that it corresponds to the closing pressure, i.e. pressure required to close the coffee container. If the coffee machine has a tamping function, the desired pressure can be selected to match the desired tamping pressure.

Thus, the passive built-in valve can act as a pressure-controlled switch to automatically switch at the desired pressure between closing and/or tamping on the one hand and brewing coffee on the other hand. In other words, the passive valve opens when the desired pressure is reached, such as the desired closing or tamping pressure. Then water is supplied. The passive built-in valve eliminates the need for user interaction to switch when needed. It also avoids the need for complex and/or expensive controlled devices, (pressure) sensors, active valves, etc. However, it allows you to use the same pump for brewing and closing/tamping. It also allows for pressure adjustment, which can promote reliable and repeatable brewing results because the correct tamping and brewing pressure will be set automatically, regardless of the amount of ground coffee in the coffee vessel and/or the type of coffee, grind size, etc.

This concept can be applied to any coffee machine with an automatic closing and/or tamping function and thus can be applied to manual, fully automatic or hybrid types of espresso or coffee machines.

In one example, the first fluid connection may be between a water reservoir, or more specifically a water pump, and a hydraulic actuator, bypassing the water heater. In this way, cold water can be used for closing and/or compaction, which can help reduce the energy consumption of the machine.

The second fluid connection may be through a water heater so that hot water can be used for brewing. The second fluid connection may, for example, be located between the water reservoir or, more specifically, the water pump and the water supply head. In such a case, there may be two parallel channels from the water tank, or more specifically the water pump, only one of which includes the water heater. The water pump is used in both fluid connections, and this common connection branches into two parallel connections at a branch point downstream of the water pump but upstream of the water heater.

In another example, the second fluid connection may be located between the hydraulic actuator and the water supply head. Heating may then occur between the hydraulic actuator and the water supply head, or in other words, the water heater may be included in a second fluid connection downstream of the hydraulic actuator. This helps avoid cooling the water during the closing and/or compaction process and can reduce energy consumption.

In another example, the branch point of the first and second fluid connections may be located downstream of the water heater. In this case, preferably the water heater is controlled so that cold water is used for closing and/or tamping, and hot water is used for brewing.

In all embodiments, the coffee machine may further comprise a controller. The controller may be configured to turn off the water heater during activation of the hydraulic drive and turn on the water heater while supplying water to the water supply head. In general, this can save energy. In examples where both the first and second fluid connections pass through the water heater, the controller may prevent heating of the water used to control the hydraulic actuator. This can also prevent the water inside the water heater from turning into steam. For example, if a water heater is left on while water is not passing through it, it can become so hot that the water that does eventually pass through it will reach boiling point, even at high pressure, and turn to steam. Using steam to brew coffee should be avoided because it usually reduces the quality of the coffee. This may also cause steam to be blown out of the dispensing spout.

A passive valve may have a status detection system to determine whether the valve is open or closed. In such a case, the controller can obtain valve status information from the status detection system. This valve status information can be used to control water heater and/or pump operating time and/or other control functions.

In addition, the coffee machine may further comprise a stabilization system configured to maintain closing and/or tamping pressure while delivering water to the water supply head. In this way, a predetermined pressure or brewing pressure can be maintained in the coffee vessel (ie, brewing chamber) during brewing.

The stabilization system may comprise, for example, a shut-off valve or a mechanical lock.

The water supply head, for example, contains a water distribution disc. The water distribution disc provides a water supply area for the ground and possibly pressed coffee. The water supply head may also contain a filter. The filter allows water to pass through and also holds the ground coffee so it can be compacted.

The water supply head, for example, is fixedly fixed relative to the main body of the coffee machine, and the hydraulic actuator of the closing and/or tamping system is designed to displace the coffee container relative to the fixed water supply head so as to ensure the closing of the coffee container and/or tamping of the contents therein. ground coffee.

This feature can advantageously be applied to any coffee machine with a closing and/or tamping system without limiting claim 1 of the present invention. Thus, according to an aspect of the invention, a coffee machine may be provided comprising:

coffee container;

water heater;

a water supply system having a water supply head for supplying heated water to the coffee vessel; And

closing and/or compaction system;

wherein the water supply head is positionally stationary, for example, relative to the body of the coffee machine, and the closing and/or tamping system contains a drive device for displacing the coffee vessel or part of the coffee vessel relative to the water supply head in such a way as to ensure closing of the coffee vessel and/or tamping the ground coffee contained in the coffee container.

In this way, the coffee vessel, rather than the water supply head, is moved to realize the coffee vessel closing process and tamping process. This means that there is no need to move the fluid passages in the machine, simplifying the design.

Preferably, the displacement of the coffee vessel or part thereof is visible, so that the closing and/or tamping process becomes a visible part of the coffee preparation process.

The displacement of the coffee vessel or part thereof may be an upward or downward displacement. This can be as simple as linear movement of the coffee container to and from a stationary water dispensing head. However, other displacements are also possible, such as rotational movement or even lateral movement. The drive device may be any suitable drive device, for example an electric motor or a hydraulic drive as described above.

In all examples, the coffee machine may include a main body having an external mounting hole, wherein the coffee container is designed to be releasably secured to the external mounting hole.

The coffee vessel functions as a brewing chamber, but is external to the machine (see below for details). It can be filled by the machine (in a hybrid type machine) or by the user (in a manual type machine). It is removed and emptied by the user after brewing. Thus, the coffee machine may be a manual or hybrid machine as explained above, but with an integrated closure and/or tamping system, so that closure and/or tamping can be reliably and repeatably accomplished by relative movement between the water head and the coffee receptacle . In this way, the critical steps (tamping, brewing and, if necessary, grinding) are carried out automatically by the machine. Only the non-critical step of unloading used coffee grounds must be performed manually by the user. As a result, good, consistent quality coffee can be prepared reliably, but with a less complex and therefore more affordable machine than a fully automatic espresso machine, because the user unloads the coffee waste himself. Thus, there is no need for a complex unloading device or automatic movement of the brewing chamber.

A coffee container, for example, contains a filter or filter basket. The coffee container may further comprise a support for placing a filter or filter basket. The filter or filter basket may be offset from the support, or they may be offset together.

The support may have a handle. It can facilitate the connection of the coffee container to the installation hole.

Another option is to have the filter or filter basket separated from the coffee receptacle, for example inserted into the machine body before installing the coffee receptacle. Thus, there are various options for the coffee container. It defines the brewing chamber and holds the ground coffee to be compacted and brewed, but it may or may not contain a filter.

In all embodiments, the coffee machine may further comprise a container for beans and a grinder having an outlet for ground coffee.

The drive device, or more specifically the hydraulic actuator, may be configured to move the coffee receptacle between a first position during ground coffee dispensing below the ground coffee outlet and a second position with the top of the coffee receptacle above the ground coffee outlet during supplying heated water to the coffee container.

Thus, the steam rising from the coffee vessel during the brewing process does not enter the grinder and container, thereby maintaining the freshness of the coffee beans. By providing this function as part of the upward movement of the coffee vessel for the closing and/or tamping process, moving the coffee vessel provides many advantages.

The coffee receptacle or drive device may, for example, physically block or otherwise obstruct the ground coffee outlet while heated water is being supplied to the coffee receptacle. This further insulates the coffee in the grinder and container from the steam generated during brewing.

The above-mentioned passive inline valve with status detection may include:

input channel;

output channel;

a valve element between the inlet and outlet channels, which is offset to isolate the inlet and outlet channels and configured to connect the inlet and outlet channels in response to pressure present in the inlet channel; And

Built-in valve status detector to provide feedback on valve status.

This provides a passive valve for use in the hydraulic circuit of a coffee machine with an integrated, and therefore compact and inexpensive, valve status detector. This allows the status of the valve to be monitored so that control actions that depend on the condition of the valve can be performed.

A passive valve (hereinafter also referred to as a passive valve device) may include first and second sensor terminals configured to move toward and away from each other in response to movement of the valve element. This allows the formation of a contact sensor or a capacitive sensor.

The valve element, for example, includes a valve membrane between an inlet port and an outlet port and has an open state and a closed state, wherein the passive valve device further comprises:

a drive element driven along the axis of the drive element by the displacement of the spring to drive the valve membrane to a closed state, the valve membrane being movable to an open state against the displacement of the spring in response to pressure present in the inlet passage;

cam on the drive element;

first and second sensor terminals, each of which is installed in the same position along the axis of the drive element, wherein one of the first and second sensor terminals is configured to be deformed or moved by a cam perpendicular to the axis of the drive element, thereby changing the distance between the first and second sensor terminals, wherein the first and second sensor terminals together form a valve condition detector.

The cam allows the valve condition detector to operate with lateral movement, thereby limiting the space occupied by the detector.

An alternative is a differential pressure sensor, in which the sensor pins are moved by two different drive elements.

In this way, the cam provides an external drive that moves with the operation of the valve, so that adding a valve condition detector does not disrupt the internal operation of the valve. The sensor leads are outside the fluid paths.

Each of the first and second sensor leads, for example, is mounted in a fixed position along the axis of the drive element. This ensures a compact design.

For example, the first and second terminals of the sensor are configured to make and open a contact through the action of a cam. Thus, the valve status detector is a contact/non-contact sensor that provides a binary output representing the status of the valve. An alternative is to provide an analog signal, for example based on a change in capacitance or resistance as a function of bias.

The first and second terminals of the sensor, for example, are configured to close the contact in the open state and open the contact in the closed state. Thus, the valve is normally closed (i.e. when there is no inlet pressure). The open contact ensures zero current consumption in this normally closed state and also protects the contacts from corrosion.

The first sensor terminal may include a contact arm that is biased inwardly to contact the second sensor terminal when the contact arm is not engaged with the cam, and moved outward from the second sensor terminal against the displacement of the contact arm when the contact arm is engaged with the cam. Thus, the cam moves the contact arm against displacement as the tongue is pushed outward, and the contact arms spring back when the cam is removed.

For example, the first terminal of the sensor includes a main lever connected to the contact lever by a spring bend. Thus, the cam moves both arms together against the bending displacement as the tongue is pushed outward, and both arms spring away from each other as the cam is removed. This provides a single component for each sensor pin. The same terminals may form a male connector on the lateral outer edge of the valve device.

The contact lever may include an inclined tongue for engaging with the cam to push the contact lever outward.

In all of the above examples, the coffee machine may include a controller configured to control at least one of:

heating water;

grinding coffee beans;

dispensing ground coffee into the coffee container;

displacement of the coffee container relative to the water supply head and

hot water supply.

Thus, the coffee preparation process can be fully or partially automated. In particular, critical stages (tamping, brewing and, if necessary, grinding) can be automated.

Some of the examples above use an external mounting hole for the coffee receptacle. The coffee container is attached to the outer mounting hole and removed from the mounting hole by the user, so the coffee container can be considered an external part of the coffee machine. By this we mean that the coffee container can be inserted and removed from the main body of the coffee machine manually and without any tools. Inserting and removing the coffee receptacle thereafter is a normal part of the user's process in operating the coffee machine for each brewing operation.

These and other aspects of the invention will be obvious and explained with reference to the embodiment(s) described below.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention and a clearer idea of how it may be practiced, reference will now be made, by way of example only, to the accompanying drawings, in which:

in FIG. 1 shows the general design of a coffee machine to which various embodiments of the invention can be applied;

in FIG. 2A-2C show three examples of possible hydraulic circuits;

in FIG. Figure 3 shows the stages of the closing and compaction process;

in FIG. Figure 4 shows an example of an alternative closing and compaction movement;

in FIG. 5-8 show how the closing and compaction approach of FIG. 3 is implemented using the hydraulic circuit of FIG. 2;

in FIG. 9 is a schematic view of a passive valve with a valve status detector;

in FIG. 10 shows the design of the passive valve in more detail;

in FIG. 11 shows the sensor outputs;

in FIG. 12 shows how the contact occurs (left image) and breaks (right image);

in FIG. 13 shows three possible designs of the contact protrusion in a top view and in section;

in FIG. 14 shows the cam of the drive element;

in FIG. 15 is a top view of the valve body and shows the lateral male connector formed by the two sensor terminals;

in FIG. 16 shows the male connector in more detail; And

in FIG. 17 shows how the sensor leads are pushed through the holes to form a male connector.

IMPLEMENTATION OF THE INVENTION

The invention is described below with reference to the drawings.

It should be understood that the detailed description and specific examples indicating exemplary embodiments of the apparatus, systems and methods are presented for purposes of illustration only and are not intended to limit the scope of the invention. These and other features, aspects and advantages of the apparatus, systems and methods of the present invention will become more apparent from the following description, the appended claims and the accompanying drawings. It should be understood that the drawings are schematic only and are not depicted to scale. In addition, it should be understood that the same reference symbols are used throughout the figures to designate the same or similar parts.

The present invention particularly relates to a coffee machine that includes a water tank, a water heater, a water pump, a coffee vessel for receiving ground coffee, and a water supply system having a water supply head for supplying heated water to the coffee vessel. The closing and/or tamping system is designed to close the coffee receptacle and/or compact ground coffee in the coffee receptacle by allowing relative movement between the water supply head and the coffee receptacle. The closing and/or tamping system comprises a hydraulic actuator, wherein a water outlet from the water pump is connected to the hydraulic actuator through a first fluid connection, and a water outlet from the water pump is connected to the water supply head through a second fluid connection , which includes a passive built-in valve. The passive built-in valve opens when the pressure reaches the desired tamping pressure.

In FIG. 1 shows the general structure of a coffee machine to which the invention can be applied. The example of FIG. 1 can be a manual espresso machine or a hybrid espresso-espresso machine, depending on how the grind is done. Alternatively, the invention may be applied to a fully automatic machine (not shown).

The coffee machine 10 includes a main body 12 having an outer mounting hole 14 for receiving a coffee container 16. The shown machine further includes a steam nozzle 24.

The coffee container 16 may include a filter or filter basket 17 (see FIGS. 2 and 3). It may also include a support 18 for housing a filter or filter basket. The coffee container 16 may further include a lower spout 20 for dispensing brewed coffee. It may further include a handle 19. Thus, the coffee receptacle 16 may correspond to a conventional coffee cone, as shown in the drawings. In use, the coffee container 16 may be installed in the outer mounting hole 14, for example, by means of a bayonet connection.

The term "coffee vessel" as used herein is generally used to refer to a container that is filled with ground coffee and then closed to form a brewing chamber in which coffee is brewed.

In the case of a manual machine, this brewing chamber can be considered "external" since it is formed by the outer part, i.e. a removable coffee container (which can be shaped like a regular cone). In the case of a hybrid type machine, the brewing chamber can be considered at least partially external, since it is formed by an external removable part. However, the ground coffee is delivered internally. For both types of machines, unloading of the tablet after brewing is done externally by the user. In the case of a fully automatic machine, the brewing chamber can be considered internal. The coffee vessel is an internal part of the machine that is not removed before and after each brew cycle.

The term "coffee vessel" is intended to cover all of these possibilities, so the actual name of the component depends on the type of machine used. The coffee container may include a portion that already contains coffee. This may include, for example, a filter or filter basket.

The main body 12 includes a hydraulic circuit providing fluid connections between a water source (typically a water tank), an internal water heater, and a water supply system having a water supply head for supplying heated water to the coffee vessel 16.

In FIG. 2A-2C show three examples of possible hydraulic circuits. Throughout the various drawings, the same reference symbols are used to identify the same components. In FIG. 2A-2C show examples of hydraulic circuits with an internal grinder but an external coffee container, and are thus all suitable for use in a hybrid coffee machine.

In FIG. 2A shows a water tank 30, a flow meter 32 (to control flow and dosing), a water heater 34, a water pump 36, and a controller 38. The flow meter 32 may provide flow measurement to the controller 38, and the controller 38 may control the heater and pump to perform the coffee brewing process. . The water heater can be, for example, a flow-through heater, for example a thermoblock. Flow meter 32 is optional. Alternatively, dosing and flow control may be accomplished by suitable control of pump 36 (eg, power level and pump run time).

The water supply system includes a fluid passage for supplying heated water to the water supply head 40, which in turn supplies the heated water to the coffee vessel 16. The water supply head contains a water distribution disc. The water distribution disc provides a water supply area for the ground coffee. The water supply head may additionally contain a filter that allows water to pass through and also retains the ground coffee so that it can be compacted during tamping.

A closing and tamping system is provided to compact the ground coffee in the coffee container by allowing relative movement between the water supply head 40 and the coffee container 16. This relative displacement closes the coffee container to form a closed chamber, i.e. brewing chamber. Additionally, it applies force to the ground coffee to perform tamping. In the specific example shown, the relative movement is achieved by moving the coffee container 16 instead of moving the water supply head 40.

The closing and tamping system includes a hydraulic actuator 42 including a piston that is actuated by hydraulic pressure. The hydraulic actuator may also include a return spring (not shown) to assist in retracting the piston after brewing.

The water outlet from the water pump 36 is connected to the hydraulic actuator 42 through a first fluid connection 44. The water outlet of the water pump is also connected to the water supply head 40 through a second fluid connection 46. The second fluid connection includes a passive integral valve 48. The passive integral valve opens when the pressure on the inlet side of the hydraulic actuator (ie, at the branch point 50A) reaches a desired pressure, such as a desired ramming pressure.

Below this pressure, valve 48 remains closed. In this case, hysteresis may occur such that valve 48 opens at a first threshold pressure (opening pressure) but only closes again when a lower second threshold pressure (closing pressure) is reached. Alternatively, there may be only one threshold pressure.

Thus, the water pump 36 is used to both supply water for brewing and supply water for closing and tamping. The passive inline valve 48 automatically switches between these two water supply functions without the need for user interaction or electrical actuators. The passive valve 48 opens, for example, when the tamping pressure is reached, i.e. upon completion of compaction. Then, water is supplied to the water supply head through the open valve 48. While water is supplied to the water supply head, tamping pressure is maintained.

In cases where tamping of ground coffee is not required, the same system can be used for a simple coffee vessel 16. In such a case, the passive integral valve 48 may open when the closing pressure is reached.

It is also possible to close the coffee container using another mechanism, for example manually. In such a case, the above system can only be used for tamping ground coffee. The passive integral valve 48 can then be opened again when a suitable tamping pressure is reached, i.e. upon completion of compaction.

Passive valve 48 operates as a pressure-controlled system in that it responds to prevailing pressure. In this way, closing and/or compaction is reliable and repeatable. With pressure control, the desired closing and/or tamping pressure can be applied to any volume of coffee in the coffee container, which is difficult to achieve if position control is used.

In the example shown in FIG. 2A, the first and second fluid connections 44, 46 meet at a branch point 50A downstream of the heater 34. Water is directed from the same branch point 50A to either the hydraulic actuator 42 or the water supply head 40. To avoid using hot water for the closing and/or tamping process, the controller 38 may turn off the water heater 34 while operating the hydraulic actuator 42 and turn on the water heater while supplying water to the water supply head 40.

To know when to turn the heater on and off, the passive valve 48 may include an open/closed state detection system, and the controller 38 may receive valve state (open/closed) information 52 from the state determination system. A suitable example of a passive valve with a status detection system is described below. Alternatively, the hydraulic actuator 42 may be provided with detection means for determining the difference between closing/ramming on the one hand and sealing on the other hand, for example based on the position of the piston within the hydraulic actuator.

In FIG. 2B shows a modification of the hydraulic circuit of FIG. 2A, in which the first fluid connection 44, instead of the position shown, is between the water reservoir 30 (or more specifically, the water pump 36) and the hydraulic actuator 42, bypassing the water heater 34, since hot water is not required to operate the hydraulic actuator 42. However, the second fluid connection 46 is located between the water reservoir 30 (or more specifically, the water pump 36) and the water delivery head 40 through the water heater 34.

Thus, in FIG. 2B water is directed from various points in the hydraulic circuit. The first fluid connection 44 includes the pump 36, but is located between the water reservoir 30 and the hydraulic actuator 42 without passing through the water heater 34. The second fluid connection 46 also includes the pump 36, but is located between the water reservoir 30 and the delivery head 40 water and passes through the water heater 34. Thus, there are two parallel fluid connections from the water tank 30, only one of which includes the water heater 34. A water pump 36 is used in both fluid connections, and this common portion of the fluid connection the fluid bifurcates into two parallel fluid connections at branch point 50B downstream of the water pump but upstream of the water heater.

In FIG. 2C, the first fluid connection 44 is located between the water reservoir 30 and the hydraulic actuator 42 without passing through the water heater 34 and turns on the pump 36. The second fluid connection 46 is located between the hydraulic actuator 42 and the water supply head 40 and passes through the water heater 34 Thus, two fluid connections are located in series, one on each side of the hydraulic actuator 42. The pump 36 is located in the first fluid connection 44, and the heater 34 is located in the second fluid connection 46.

Cold water can be used again for capping and/or tamping, and hot water can be used for brewing. Heating is carried out between the hydraulic actuator and the water supply head. This avoids cooling the water during the closing and/or compaction process and reduces energy consumption.

As mentioned above, after opening the valve 48, it is necessary to maintain the closing or tamping pressure while supplying water to the water supply head 40. A stabilization system can be used for this purpose. As will be explained in more detail below, this stabilization system may include various active and/or passive flow components, such as a check valve, a mechanical lock, a check valve 51, and/or a flow restrictor 53. Additionally, the piston area ratio may play a role, as will be explained below. All stabilizing components can be adjusted to maintain, for example, the desired tamping (or closing) force while allowing sufficient water to flow into and through the brew chamber. Some of the above valves may be implemented as an overpressure valve to act as a safety device and limit the amount of force applied during closing, tamping and/or brewing.

When water is pumped into the hydraulic actuator 42, the actuator closes so that pressure can build up and move the piston upward. At the end of the brew cycle, this water must be drained from the actuator to allow the piston to retract. If necessary, a return spring (not shown) may be provided to assist in retracting the piston.

To drain water from the hydraulic actuator, a return path may be provided between the hydraulic actuator 42 and the water reservoir 30, as shown in FIG. 2A-2C. A valve 60 may be provided to open or close the return path. The valve 60 may comprise, for example, an electronic shut-off valve. However, such a valve is relatively expensive. Therefore, preferably the valve 60 is implemented as a mechanical lock, which can be actuated either by a separate handle or by attaching/detaching the coffee container 16. More specifically, the valve 60 may be closed when the coffee container 16 is attached and open when the coffee container is detached. Thus, the opening and closing of valve 60 can be controlled in response to or during attachment/detachment of the coffee container by the user. Since this user action is already a required part of the coffee brewing process in any case, no additional action is actually required from the user.

In all examples of FIGS. 2A-2C, in addition to the passive integral valve 48, there is only one active valve 60. This active valve can be actuated by insertion and removal of the coffee receptacle as described above. Hydraulic diagrams according to FIG. 2A-2C may further include one or more passive parts, in particular one or more check valves (one-way valves) 51 and/or flow restrictors 53, as indicated by the dotted lines.

The check valves 51 shown are configured to prevent backflow from the hydraulic actuator 42. Such backflow would otherwise cause the piston to lower and open the brew chamber. Backflow can occur, for example, in coffee machines that include a pre-brewing step. During this pre-brewing phase, the water pump 36 is turned on briefly to dispense a small amount of water onto the ground coffee, then turned off to allow the ground coffee to dissolve, and then turned on again to begin the actual brewing process. While the pump is turned off, the pressure may drop and backflow from the hydraulic actuator 42 may occur. In the examples shown, this is prevented by the check valve(s) 51.

The check valve(s) 51 may also provide an advantage if the piston area ratio is not optimal, i.e. the ratio between the cross-sectional area of the interior of the hydraulic actuator 42, which is subject to the water pressure supplied by the pump, and the cross-sectional area of the interior of the brewing chamber, which is subject to the brewing pressure during brewing. If this area ratio is not suitable, the force applied to the piston by the brew pressure (and, if necessary, the return spring) may be greater than the force applied to the piston by the water pressure supplied by the pump. By preventing any water from escaping from the hydraulic actuator 42 by the check valve 51 as described above, the piston can be prevented from retracting. In such a case, an overpressure valve may also advantageously be provided to act as a safety valve to prevent the pressure inside the hydraulic actuator 42 from reaching too high values.

Alternatively or additionally, the area ratio can be optimized. The significance of this area ratio is explained below. During tamping, the ground coffee is compressed. The more compressed the coffee is, the more back pressure it generates when water is pumped through it. Since the entire system is connected to the same pump, increasing the brewing pressure (created by the ground coffee as the water flows through) also increases the pressure in the hydraulic drive used to tamp the coffee. This causes more force to be applied to the ground coffee, compressing it even more. This in turn increases brewing pressure, resulting in increased tamping pressure, etc. This may lead to the system itself being locked after enough time has passed.

By adjusting the area ratio, the ratio of the aforementioned opposing forces can be adjusted, allowing the piston to move slightly during brewing. This is one way to prevent the system from locking up. In such a case, a safety device may also preferably be provided to prevent accidental opening of the brewing chamber caused by movement of the piston.

Alternatively or additionally, a hydraulic limiter (resistance) 53 may be added to the circuit, as shown in FIG. 2B with dotted lines. This restrictor 53 creates a pressure difference depending on the amount of water flowing through it. The higher the flow rate, the greater the pressure difference between the pressure in the brewing chamber and the pressure in the hydraulic drive 42 (the pressure in the hydraulic drive 42 is higher). If the piston areas are equal, the force exerted by the water pressure in the hydraulic drive will become greater than the force exerted by the pressure in the brewing chamber. This will create a net upward movement of the piston, further compressing the ground coffee. This in turn will increase the pressure in the hydraulic drive and brew chamber as the pump has to work harder to push the water through the ground coffee. Since pumps in a coffee machine have lower flow rates at higher pressures (and vice versa), increasing the pressure will result in lower flow rates. As a result, the flow through restrictor 53 will also be lower, which will reduce the pressure drop and the resulting force acting on the piston. Thus, the flow restrictor 53 can help balance the pressure differential that may exist across the piston with a given area ratio.

It is clear from the above that the pressures and forces exerted on the piston during use, if not well balanced, can cause the brew chamber to inadvertently open during brewing or cause the piston to create such a tamping force that water cannot pass through the ground coffee, thereby thereby blocking the system. The pressures, forces and flow rates prevailing in the system may also depend on the amount of ground coffee in the brewing chamber and/or the grind size.

Pressures, forces and flow rates can be balanced by adjusting the piston area ratio, piston return spring force (if present), and/or size of restrictor 53. Additionally, check valves 51 can be added to prevent backflow from the actuator.

In FIG. 2A-2C also show a bean container 54 and a bean grinder 56 having an outlet 58 for ground coffee. Thus, in FIG. 2A-2C show a hybrid type design with an internal bean grinder and a brewing chamber in the form of a coffee vessel 16 that is removably mounted in an external mounting hole 14 and emptied externally by the user as part of the normal operation of the coffee machine.

In FIG. Figure 3 shows the stages of the closing and compaction process.

In FIG. 3A, the coffee receptacle 16 is shown in the form of a cone with a support 18, a filter 17, and a handle 19. The coffee receptacle 16 is installed by the user in the installation hole 14. The ground coffee is then fed into the coffee receptacle by a grinder 56, which can be controlled by a controller 38.

In FIG. 3B, the drive device moves the coffee container 16 towards the water supply head 40. This ensures the coffee container is closed and the ground coffee is compacted. At a minimum, filter 17 is shifted, i.e. a container immediately surrounding the retained coffee, as shown in FIG. 3. However, alternatively the entire coffee container 16 (corresponding to the horn in the case of FIG. 3) can be displaced.

The water supply head 40 may include an inlet filter for the coffee vessel, and the filter 17 forms or contains an outlet filter. Tamping occurs between these two filters. The coffee container may not even include a filter, since both filters may be provided as separate elements, for example separately installed in the main body of the machine. Thus, many different configurations are possible.

In FIG. 3C, coffee is brewed using hot water supplied to the water supply head 40 under pressure.

In FIG. The 3D drive device returns the filter 17 to its original position so that the coffee container 16 can be removed to remove the coffee tablet.

By moving the coffee vessel instead of the water head to perform the closing and/or tamping process, no movement of the fluid passages in the machine is required, which simplifies the design. In the case where the coffee receptacle is visible from the outside, as is typically the case in a hybrid and manual espresso machine, the closing and/or tamping process may become a visible part of the coffee brewing process since movement of the outer coffee receptacle may be visible or nearly visible.

In the example shown, the drive device moves the coffee container up and down. This is shown as a simple linear movement of the coffee container to and from the stationary water supply head 40. However, other displacements are also possible, such as rotational movement or even lateral movement.

In FIG. Figure 4 shows an example of an alternative movement with a rotary device. Other movements are possible, including horizontal and vertical.

However, there is an additional benefit that can be achieved by moving the coffee container up and down. This additional advantage can be seen from FIG. 3, in particular from FIG. 3B and 3C.

The drive device moves the coffee container between the first and second positions. In the first position, ground coffee is supplied, as shown in FIG. 3A. At this time, the top of the coffee vessel 16 is under the ground coffee outlet 58 so that the ground coffee can be delivered by gravity. In the second position, heated water is supplied to the coffee vessel through the water supply head, as shown in FIG. 3C. At this time, the top of the coffee vessel is above the ground coffee outlet 58.

Thus, the steam rising from the coffee vessel during the brewing process of FIG. 3C, cannot enter the coffee in the grinder 56 or the coffee bean container, thereby maintaining the freshness of the coffee beans. This also prevents blockage that can occur as a result of the coffee beans becoming hydrated. Thus, moving the coffee vessel during closing and/or tamping provides many advantages.

The coffee container or drive device may also be configured to physically close the ground coffee outlet 58 while heated water is supplied to the coffee container through the water supply head. This further insulates the coffee in the grinder and container from steam generated during brewing.

In FIG. 5-8 show how the closing and compacting step is implemented using the hydraulic circuit of FIG. 2A is for example only.

In FIG. 5 shows the insert of a coffee container 16. There is no fluid flow in the circuit and valve 60 is closed.

In FIG. Figure 6 shows the process of closing and compacting. The hydraulic actuator 42 in this example lifts the entire coffee container 16. The pump operates to pressurize the hydraulic actuator 42, but the heater 34 remains off. Valve 60 remains closed.

In FIG. 7 Tamping pressure has been reached. Passive valve 48 opens, the heater is turned on (eg, based on detection that valve 48 has opened), and brewing occurs. This way the cup of coffee is filled.

In FIG. 8 valve 60 is open. This may be accomplished by manual action by the user, for example using a manually operated switch, or by performing the initial step of removing the coffee container 16, for example rotating in its bayonet connection, as described above. Thus, water from the hydraulic actuator 42 can flow back into the water tank 30 through the valve 60. Draining the water from the hydraulic actuator causes the piston and coffee container 16 to lower and the brewing chamber to open. In this case, some water vapor may leak. This water vapor moves upward from the remaining ground coffee in the grinder.

Once completely lowered, the user can remove the coffee container and empty it.

In all of the above examples, the water supply head 40 is fixed relative to the main body 12, and the hydraulic closing and/or tamping system actuator 42 displaces the coffee container 16 (or part thereof) relative to the water supply head 40 to ensure the closure of the brewing chamber and tamping. In other examples (not shown), the coffee receptacle 16 may be fixed or stationary, and the hydraulic actuator 42 may be configured to move the water supply head 40 or a portion thereof (e.g., an inlet filter) relative to the coffee receptacle 16 to provide closure. and/or tampers.

In other examples, the coffee machine may be a manual type coffee machine without bean container 54 and grinder 56.

In other examples, the coffee machine may be a fully automatic coffee machine with a coffee receptacle that is mounted internally instead of being removably attached to the outer mounting hole 14.

In FIG. 9 is a schematic illustration of a passive valve with a valve status detector suitable for use as valve 48 in the typical circuits of FIG. 2A-2C and 5-8.

The passive valve shown in FIG. 9 is based on the valve design detailed in WO 2018/122055.

The passive valve device includes a housing 90a, 90b that defines an inlet port 92 and an outlet port 94.

The valve diaphragm 96 is located between the inlet port and the outlet port and has an open state and a closed state. In the example shown, the valve membrane 96 is disc-shaped, with an inlet port 92 opening toward a central portion of the valve membrane and an outlet port opening toward an edge region of the valve membrane.

The actuator 98, in the form of a piston in this example, is driven along the actuator axis 100 by the displacement of a spring (not shown) to force the valve diaphragm to a closed state. The valve diaphragm moves open against spring displacement in response to pressure present in inlet port 92.

To the extent described above, the design of the valve corresponds to the description in WO 2018/122055, to which reference is made.

This design may be modified by incorporating a sensing mechanism, which may be based on capacitance sensing, optical detection, or magnetic sensing, based on the lower and/or upper position of the actuator 98. The sensing mechanism is selected to prevent any significant influence on the valve opening pressure.

One example of a suitable modification to the design of WO 2018/122055 is to provide first and second sensor terminals, generally designated 102. In this example, they move towards and away from each other with the movement of the drive element 98.

This can be used to provide contact/non-contact recognition to produce a binary detection signal. Alternatively, capacitance measurement can be used to obtain a range of detection values for the valve opening distance.

In FIG. 10 shows in more detail the approach based on contact/non-contact recognition. The drive element 98 is biased against the membrane 96 by a spring 103. The drive element has a cam 104 on its outer surface. It is used to interface with the design of the first and second terminals of the sensor.

Each sensor lead may be mounted in a fixed position along the axis 100 of the drive element. One of the first and second sensor terminals is deformed or moved perpendicular to the axis of the drive element under the action of the cam. This changes the distance between the first and second sensor leads.

This provides the passive valve with a built-in, compact and low-cost valve condition detector. This allows the operation of the valve to be monitored so that control actions can be taken that depend on the condition of the valve, as explained above. Cam 104 allows the valve status detector to operate with lateral movement, thereby limiting the space occupied by the sensor.

In FIG. Figure 11 shows the sensor outputs.

The first sensor terminal 110 includes a contact arm 112 that moves inwardly (i.e., toward the axis 100) to contact the second sensor terminal 120 when the contact arm 112 does not engage the cam, and moves outward from the second sensor terminal 120 against the offset. contact lever when the contact lever interacts with the cam. The contact arm 112 shown has a contact protrusion 113 and a tongue 114. The cam cooperates with the tongue 114 to move the contact arm against displacement when the tongue 114 is extended outward, and the contact arm returns back when the cam is removed.

The first sensor terminal in the example shown comprises a base lever 116 coupled to the contact lever 112 by a spring bend 118. Thus, the cam forces the two first sensor terminal arms 112, 116 together against the bias of the bend when the tab is pushed outward and the two levers spring away from each other. when the cam is removed. This makes it possible to use a single component for each sensor lead.

Opposite ends of the sensor leads 110, 120 form a male connector with integral connection pins 122. This male connector is preferably located on the lateral outer edge of the valve assembly.

The first and second sensor terminals 110, 120 make and break contact through the action of the cam 104. Thus, in this example, the valve status detector is a contact/non-contact sensor providing a binary output representing the valve status. An alternative is to provide an analogue signal, for example based on the change in capacitance or resistance as a function of bias and therefore the distance between the sensor leads.

In FIG. Figure 12 shows how contact is made (left image) and contact is broken (right image).

In FIG. 13 shows three possible designs of contact protrusion 113 in top and cross-sectional views. It may be a truncated pyramid, a flat-topped hemisphere, or a rectangular comb. The contact protrusion may be formed in the form of a recess (which then protrudes from the opposite side) or a fold.

In FIG. 14 shows a cam 104 of the drive element 98. A set of cam elements may be located around the periphery. Only one is required to interface with the sensor pins. However, multiple cams allow the drive element to be adjusted to different angular positions. The cams may be used as alignment elements to ensure proper alignment of one of the cams with the tongue 114 of the first sensor terminal 110. They can also be used as guides so that the angular position of the drive element is fixed as it slides up and down (of course this is only necessary when it is circular). For example, a guide wall in the housing 90a, 90b may extend between a pair of cams.

The passive valve is typically closed because, in the absence of inlet pressure, the spring forces the actuator 98 against the valve diaphragm 96. Thus, the drive element extends downward (for the orientation used in the drawings). This means that the cam 104 interacts with the tongue 114 so that contact between the sensor leads is broken. This ensures that the sensor draws zero current in this normally closed state of the passive valve.

This also means that the contacts (contact protrusion 113) are normally separated. Upon contact, corrosion of the material occurs faster. Thus, limiting the amount of contact time limits corrosion and limits the amount of design force required to provide corrosion resistance over the life of the device. For example, a thinner layer of gold or other passivating metal may be sufficient.

In FIG. 15 is a top view of the valve body 90a, 90b and shows a side male connector 150 with holes 152 for the pin connectors 122 of the two sensor terminals 110, 120. The male connector 150 may be, for example, a JST connector. The JST connector usually has solid pins. However, the sensor terminals 110, 120 are made in the form of sheet metal. In order for their ends 122 to act as square contact pins, an L-shaped cross-section of the terminal stem 110, 120 may be used, as shown in FIG. 11. This resists bending. A flat profile may be used for the arms 112, 116.

In FIG. 16 shows male connector 150 in more detail, with connector pins 122 inserted through holes 152.

In FIG. 17 shows how the ends 122 of the sensor leads 110, 120 protrude through the holes 152 to form a male connector.

The descriptions of the hydraulic circuit examples above and the use of a passive valve refer to a hybrid type coffee machine. However, many of the above concepts also apply to manual and fully automatic coffee machines.

Other variations of the described embodiments may be understood and implemented by one skilled in the art in putting the claimed invention into practice after reading the drawings, description and appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the grammatical form of the singular does not exclude the presence of the plural. A single processor or other module can perform the functions of several elements listed in the claims. The fact that certain agents are described in mutually different dependent claims does not mean that the combination of these agents cannot be used to provide an advantage. If the term "capable of" is used in a claim or description, it should be noted that the term "capable of" is intended to be equivalent to the term "capable of." No reference symbols in the claims should be construed as limiting the scope.

Claims (30)

1. A coffee machine containing: water tank (30); water heater (34); water pump (36); a coffee vessel (16) configured to receive freshly ground coffee; a water supply system having a water supply head (40) for supplying heated water to the coffee vessel; And a closing and/or tamping system for closing the coffee container and/or compacting ground coffee in the coffee container by allowing relative movement between the water supply head and the coffee container; wherein: the closing and/or tamping system comprises a hydraulic actuator (42); the water outlet from the water pump is connected to the hydraulic actuator through a first fluid connection (44); And a water outlet from the water pump (36) is connected to the water supply head through a second fluid connection (46) that includes a passive integral valve (48), wherein the passive integral valve is configured to open when the pressure reaches a desired level level. 2. The coffee machine according to claim 1, wherein the first fluid connection (44) is located between the water tank and the hydraulic actuator without passing through the water heater. 3. The coffee machine according to claim 1 or 2, wherein the second fluid connection (46) is located between the water tank and the water supply head and passes through the water heater (34). 4. Coffee machine according to any one of paragraphs. 1-3, in which the second fluid connection (46) is located between the hydraulic actuator and the water supply head. 5. The coffee machine according to claim 1, wherein the first and second fluid connections are connected to each other at a branch point (50A) downstream of the water heater. 6. Coffee machine according to any one of paragraphs. 1-5, further comprising a controller (38) configured to turn off the water heater during actuation of the hydraulic actuator and turn on the water heater while supplying water to the water supply head. 7. The coffee machine according to claim 6, wherein the passive valve (48) has a status detection system, and the controller is configured to receive information about the status of the valve from the status detection system. 8. Coffee machine according to any one of paragraphs. 1-7, further comprising a stabilization system configured to maintain closing or tamping pressure while water is supplied to the water supply head. 9. The coffee machine according to claim 8, in which the stabilization system contains a shut-off valve or a mechanical lock. 10. Coffee machine according to any one of paragraphs. 1-9, in which the water supply head (40) is positionally stationary, and the hydraulic actuator of the closing and/or tamping system is configured to move the coffee vessel (16) or part thereof relative to the stationary water supply head in such a way that the vessel is closed for coffee and/or tamping the ground coffee contained in the coffee container. 11. Coffee machine according to any one of paragraphs. 1-10, in which the hydraulic actuator is configured to move the coffee container (16) or a part thereof up and down. 12. Coffee machine according to any one of paragraphs. 1-11, comprising a main body (12) having an outer mounting hole (14), the coffee container being attached to the outer mounting hole and being removable from the mounting hole by a user. 13. Coffee machine according to any one of paragraphs. 1-12, in which the coffee container (16) includes a filter or filter basket and a support (18), wherein a hydraulic actuator is configured to move the filter or filter basket relative to the support or move the filter basket and support together. 14. Coffee machine according to any one of paragraphs. 1-13, further comprising a container (54) for beans and a grinder (56) having an outlet for ground coffee. 15. The coffee machine according to claim 14, comprising a controller (38) configured to control at least one of: heating water; grinding coffee beans; dispensing ground coffee into the coffee container; displacement of the coffee container relative to the water supply head and hot water supply.

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