Espresso coffeemaker with removable water reservoir

The present invention relates to espresso coffee machines of the type comprising a cold water reservoir, an electric pump, a boiler assembly and a filter container for receiving ground coffee to be infused by hot water under pressure from Boiler.

The boiler assembly, hereinafter called thermoblock generally consists of an electrical heating element in thermal communication with a water system, the water being circulated during operation of the pump. In the end of manufacturing of coffee drinking cycle, it is necessary to perform a pressure relief in the hydraulic system of the machine, this relaxation is making for the vast majority of coffeemakers by redirecting the flow of water under pressure to the cold water reservoir which then receives the return stream.

Such a coffee maker is known from <patcit id="pcit0001" dnum="FR2316901"><text>FR 2316901</text></patcit> where a pump is mounted in the base of the machine and a cold water tank in the vertical column connecting the base to the upper part of the machine. The reservoir is removably mounted by being positioned in a frame belonging to the machine base. The frame receiving the removable tank has a cylindrical bore in the upper part for communicating with the outlet orifice of the tank and a bottom communicating with two nozzles facing downward interconnected to the pump suction conduit and other to a return line into the tank. Functioning satisfactorily, we realized that in the situation where the user removes an untimely tank of his seat when a hot water flows under pressure arrives to the tank, the return is as a powerful and hot jet and then projected splashes may burn the user. In addition, there is rejection of the work plan of a large quantity of hot water.

To overcome this problem, several solutions have been proposed consisting, for example, to use an electronic circuit using the presence of reservoir detection sensor, the sensor information is then used by the circuit for controlling the cycle operation of the machine. These solutions complicate the realization of a coffee machine and increase the manufacturing cost.

A simplified solution is described in document <patcit id="pcit0002" dnum="FR2544604"><text>FR 2544604</text></patcit> where the tank weight pushes a control lever which actuates a switch of the electric circuit of the machine, making possible the operation of the latter only from a predetermined weight. However, the mere detection of the tank weight is not enough to ensure a proper return flow of water under pressure to the reservoir, is it still that it is properly implemented. Without proper communication establishment of a removable tank with its seat sealing, overflows of the return flow accumulate around the tank causing the seat messy leaks and cleaning problems thereafter.

The purpose of the present invention to overcome the above drawbacks and to provide an espresso coffee machine type removable tank of efficient operation while providing increased protection when the user is using the machine.

Another object of the invention is a coffee machine of the espresso easy maintenance kind, avoiding any overflow problem or uncontrolled water flow when the removable reservoir is handled by the user.

A further object of the invention is a coffee machine espresso type of simple and inexpensive construction, while being reliable in operation.

These objects are achieved with an espresso coffee machine of the type having a removable reservoir connected to a main hydraulic circuit having a pump that sucks water from the reservoir and sent to a heating unit and from here through the ground coffee contained in a filter carrier, said tank also being connected to a hydraulic circuit for returning water leaving the heating unit, because the connection device of said tank with said water circuits includes means for expanding the jet of water arriving by the hydraulic circuit to return to the reservoir and means for directing said jet towards a storage zone.

Thus, this connection device first ensures a sealed communication between the cold water reservoir of the machine and the rest of the hydraulic circuit. This sealing connection may be achieved by an O-ring belonging to said connecting device or to the reservoir, seal between two reentrant tubes in communication the two parts. The tank manifold generally includes a valve which automatically closes access to the tank when it is removed from its seat and opens the passage to the hydraulic circuit of the machine when the tank is replaced.

The connection device also has the role of communicating the cold water reservoir with the main hydraulic circuit, which connects to the suction duct of the pump and a return circuit to the tank by a pipe relaxation.

According to the invention, the connecting device comprises first means for expanding the jet of water that returns to the tank. During operation of the machine, especially late in the development cycle of the coffee beverage, the pressure must be lowered in the outgoing hydraulic circuit for the block and for this reason, the flow of hot water is returned by the flash pipe to the tank. If the reservoir is in communication with the pressure reduction conduit, this flow returns to the tank. By cons, if the tank is not in place, the powerful return flow is in any way broken by said first means which has the effect of getting a quiet stream, thereby protecting the user against splashes pressurized hot water.

The connection device of the invention further comprises second means for directing the flow of water back to a storage area. So the quiet jet obtained with the first means is then directed to an area to collect the return flows, particularly if the tank is absent or is poorly positioned or if for any reason, sealing between the latter and the connection device is broken. This prevents spillage outside of the machine or prevent the accumulation of stagnant water inside it in hard to reach areas for cleaning.

Advantageously, the expansion means direct the water jet in a direction other than the main axis of the connection device of said tank with the hydraulic circuits of the machine.

By main axis of the tank connection device including one containing axis of the tubing where the tank is arranged the valve or the damper ax. This axis is, for most applications, vertical or normal to the work plan, but it can also be arranged in another direction. Orienting the return water jet in a direction different from that of the main axis of the tank connection device that the powerful jet suffered a loss and at the same time it is deflected Officer normal to the worktop or to the seat plane of the connecting device, making it protects the user when the return jet occurs in the absence of the tank.

Preferably, said connecting device comprises a central bore providing communication on one side with said reservoir, across the bore opening out into two orifices communicating with the main hydraulic circuit and the other with the hydraulic return circuit, wherein said water jet from the expansion means are arranged in the extension of the axis of the orifice that communicates with the hydraulic return circuit.

Thus, the turbulent jet which arrives through the return line into the opening provided for this purpose in the connecting device is calmed by means of relaxation which are arranged in the axis of said orifice and having a direct effect on the jet powerful pressure. This return jet undergoes loss coming in contact with the means of relaxation, which makes it safer for the user.

Usefully, said relaxation means comprise a plurality of parallel fins arranged in alternation about a common axis.

These fins are a buffer for the powerful jet back and, by their arrangement on a shaft opening into the arrival of the return water jet orifice, forcing the water jet to follow a winding path whose Indeed a significant load loss and obtaining a sufficiently calm water jet to be oriented or recovered thereafter.

Advantageously, said common axis includes a deflector located in the tank axis of the closure flap when the latter is connected to the connection device.

Thus, with a deflector situated on the axis supporting the fins ensuring the relaxation of the water flow, particularly in the upper part of the axis facing the water tank, it is ensured the tank opening of the closure flap when its placement in the connecting device in a simple way, without using an additional part for communicating the reservoir with the rest of the hydraulic system of the machine.

Preferably, said means of directing the water jet are arranged downstream of said expansion means of the water jet in the flow direction thereof.

One would have imagined to guide the first turbulent jet of water to an area of ​​recovery and relax afterwards, but it was observed that it is more advantageous to relax the first because a water jet calm is easier to channel thereafter towards a recovery area or storage.

Advantageously, said means for directing the water jet include at least one passage communicating the interior of the bore of the connection device with a funnel surrounding said bore.

Thus, the water jet relaxed within the central bore of the connection device, is directed to a space close to the bore and concentric therewith, a passage being provided for establishing a communication between said containing spaces fluid that is returned to the tank.

Preferably, said means for directing the water jet of the coffee machine of the invention comprise a first passage situated downstream from an O-ring providing sealing between the tank and the bore of the connection device as as seen in the flow direction of the return water jet towards the tank.

Thus, when the reservoir is put in place and the seal ring provides sealing between the reservoir and the central bore of the connection device, the return stream is extended inside the tank. By cons, if the tank is absent or poorly positioned, the seal no longer provides its role, so that the return water jet is directed by a passage located right next to and downstream of the seal sealing in a storage area constituted by the funnel surrounding said bore. This first passage may be arranged to the upper edge of said bore or making an opening located closest to the location of the seal in order to avoid the return jet to perform long distances before reaching the area of storage.

Preferably, said first passage is provided between the upper part of the bore and the inner face of a plate affixed to the funnel.

In this configuration, a plate is provided in the upper part of the funnel, at least one opening being provided between the two so that the return jet of water following this opening to reach the interior of the funnel. The water jet is easily channeled toward the funnel closed by said plate, thereby avoiding any overflow or splashing inside the latter, for example following projections touching the inner walls of the funnel, etc. Usefully, said water jet directing means comprise a second passage in the form of an opening in the plate, opening located downstream of the first passage as seen in the flow direction of the return water jet to the tank.

Thus, if the return water jet is not sufficiently dampened by the means of relaxation, overflows can rise and exceed this first pass. These overflows are then collected by the said opening at a higher level than said first passage in the flow direction of the water jet, which ensures even more control of the return water jet, to channel it towards the funnel even if unexpected increase in the pressure of the latter.

Advantageously, said water jet directing means comprise channeling ribs situated on either side of a plate the port communicating with the bore of the connection device, veins arriving in the vicinity of said opening.

Thus, said possible overflows through the bore of the connection device, arrive on the upper face of the plate provided with duct ribs which collect these overflows and channel towards said opening into the funnel which receives this overflow.

Usefully, said water jet directing means communicate via a discharge port of the funnel with a removable drip tray mounted in the machine.

Thus, overflow temporarily stored in the funnel are rolled to a larger recovery tank as the funnel and which, moreover, is removably mounted relative to the body of the machine allowing the user of the drain easily. Said recovery tank includes a gutter extension forming a recuperator coming under a recovery endpiece to which is connected a discharge pipe of the funnel.

Advantageously, said recovery tank maintains the infusion collector container holder.

The infusion collector container holder is in the form of a grid maintained at its periphery by the recovery tank flange. This allows to collect in the same tank potential drops resulting from the infusion of coffee. This maintains the clean environment of the machine and easy cleaning.

The invention will be better understood in the study of the embodiments taken in no way limiting and illustrated in attached figures in which:<ul><li>1 shows a partial longitudinal sectional view of a coffee machine according to the invention;</li><li>2 is a perspective view of the rear part of the machine with the water tank removed from his seat and represented next;</li><li>3 shows a perspective view of the bottom of the base of the machine, some of the parts constituting the outer casing of the machine being removed to facilitate viewing;</li><li>Figure 4 is an axial sectional view of the connecting portion of the tank with the corresponding part of the base of the machine.</li></ul>

1 shows a coffee machine of the invention comprises a body 1 whose lower part includes a base 2 which is connected to the upper body 1 by a vertical upright 3 serving as support for a water reservoir 4 cold. The body 1 contains the hydraulic circuit of the machine comprising the reservoir 4, a pump 5, a heating unit 6, a valve 7 and a cylinder 8 for compressing the ground coffee.

The ground coffee is placed in a cup provided with a filtering wall called filter holder 9 which is, in the example described, mounted to slide in a horizontal direction in the slots of a fixed support of the brew head 10 .

The cylinder 8 has a nose mounted to slide vertically relative to the body 1 of the machine adapted to penetrate, during each operating cycle, within the filter-holder 9 in order to compress the grounds. The water supplied by the pump 5 drives the hydraulic cylinder 8 which pushes against the nose milling. Starting from a predetermined pressure value, a valve located within said nose allows the passage of water from the heating unit 6 to the filter-holder 9 where the infusion flows into a collecting container located on a support 11 of the base 2.

The coffee maker comprises a boiler or heating unit 6 for heating the water under pressure supplied by the pump 5 before injection into the ground coffee from the filter holder 9. The heating unit 6 includes heat exchangers channels 17 allowing the circulation of water inside the heating unit 6 which further comprises an electrical heating element 12 and a temperature sensor 13. the water from the pump 5 arrives through an inlet channel 14 of the thermoblock and 6 may be apparent along two paths of the latter, according to the position of the distributor 7. Either cold water exits through an outlet channel 15 which form with the inlet channel 14, a short circuit does not allow water to heat up in the heating unit or the hot water exits through an outlet duct 16 after circulating in the heat exchange channel 17 of the heating unit 6.

End coffee extraction beverage, the dispenser 7 is returned to the rest position by the user, so that hot water under pressure the hydraulic circuit is sent by an expansion pipe to the reservoir 4.

The reservoir 4 is removably mounted on the machine of the invention and it comprises, as seen in Figure 2, hooks 20 which can engage in eyelets 21 provided for this purpose in the front wall by screws screw of the vertical post 3. the tank 4 has a generally parallelepiped shape open at its top for filling purposes and closed in its lower part by a valve 23 (Figure 4) located inside a column 22. the valve 23 is normally closed under the action of a return spring 24 which maintains the upper portion 23 pressed against the bottom of tank 4 through the interposition of a sealing washer 26. When the tank 4 is in place, the column 22 lies in a bore 29 of the base 2, means being provided in the base to open the valve 23 and communicating the liquid tank 4 with the hydraulic hoses of the machine.

As seen more clearly in Figures 3 and 4, the bore 29 is formed in a concave part called funnel 30 supported by mounting studs 31 to the base 2 of the machine. The base of the funnel 30 has a plurality of openings into the conduits of the hydraulic circuit of the machine. Thus, two holes 33 and 34, are formed at the bottom of bore 29, on either side of the axis thereof, and communicate with a flash pipe 37 and the other with a conduit main circuit device 38. a hole 35 is provided for communicating the funnel 30 with a discharge pipe 39.

By driving the main circuit 38 includes a pipe is connecting funnel 30, respectively reservoir 4, pump 5, while driving by on relaxing 37 comprises a duct that connects the outlet pipe of the heating unit 6 to funnel 30. the discharge pipe 39 connects in turn funnel 30 to a waste container, as will be explained later.

The pipes 37, 38 and 39 are flexible tubes, made for example of rubber, which are connected on vertical hollow caps embodying said ports 33, 34 and 35, as seen in Figure 4. Similarly, the opposite end of each pipe is brought into communication by connection elements of the same type with its respective hydraulic circuit element.

The bore 29 is defined by the inner diameter of a cylindrical wall 40 formed approximately at the center of the funnel 30. As seen more clearly in Figure 3, the funnel 30 has an oblong shape having, along its axis principal, a bent front wall 42 and an opposite wall 42 'flat.

The funnel 30 being a relatively complex shape, it may advantageously be made of a plastic material by an injection technique.

The upper surface of the cylindrical wall 40 (Figure 4) has a groove 41 in which is located an O-ring 43. The O-ring 43 bears on the outer surface of the column 22 of reservoir 4 when it is in place on the coffee maker, this seal having the role of sealing between the reservoir 4 and the bore 29 of the cylindrical wall 40 of the funnel 30, respectively between the reservoir 4 and the rest of the hydraulic circuit of the machine. The O-ring 43 is held in place by the castellations 46 of a plate 45.

The plate 45 is positioned above the funnel 30 so as to close it at least partially, this plate 45 being fixed in turn by fixing studs provided for this purpose in the base 2. The plate 45 has in its central portion a hole 29 'through located in the extension of the bore 29 of the cylindrical wall 40 of the funnel 30 and having a diameter slightly greater than the diameter of the latter.

The inner surface of the plate 45, which faces the funnel 30 has a crown provided with crenellations 46 bordering the opening 29 '. The solid portion of these serrations 46 has the role of maintaining in place the O-ring 43, whereas the cut-outs located between two castellations 46 form passages 32 having the role to connect the interior of bore 29 with its periphery , thus with the peripheral portion of the funnel 30.

On the outer part of the plate 45 facing the reservoir 4, are formed two guide ribs 47 parallel to each other, disposed on either side of the orifice 29 'and perpendicular to the end walls 42, 42'. The plate 45 has, on the edge of the ribs 47, an opening 48 which allows new, but at a higher level, the communication with the peripheral portion of the funnel 30. For higher level it includes a level located downstream in relation to serrations 46 in the flow direction of the return flow of hot water to the tank at the end of cycle.

Furthermore and as shown in Figure 4, the base of the bore 29 is fixed a breeze jet set 50 vertical longitudinal axis coaxial to that of the bore 29 and, respectively, than in column 22 of the reservoir 4. the jet breaker assembly comprises in its upper part a deflector prominent 51 which bears on the bottom 25 of the valve 23 to cause it to open during the establishment of the tank 4. the lower portion of the entire air jet 50 comprises a plurality of fins 52 arranged eccentrically alternately one above the other, along the longitudinal axis of the air jet 50.

As seen in Figure 4, two adjacent fins touching with a part of their periphery the two opposite ends of the inner surface of the bore 29, a zigzag path being thus formed between their free ends, this path opening into the port 33 communicates with the flash pipe 37. the fins 52 may have a disc-shaped or other flat shape or left suitable for purpose. Such an arrangement requires the water jet arriving from the bottom of the bore 29 to have a winding route, cutting through the chicanes formed by the offset ends of the fins 52, which result in the loss or reduction of pressure water jet back to the tank.

Referring to Figure 3, we see that the discharge pipe 39 from the bottom of the funnel 30 and leads the liquid collected by it to a collector 55 located below a collector nozzle 54 and communicating with the latter , endpiece onto which is connected the discharge pipe 39. the funnel 30 being raised relative to the recuperator 55, the liquid collected by the funnel 30 quickly flows to the recuperator 55.

The collector 55 is common body with a drip tray 56 which constitutes an extension gutter. The drip tray 56 is preferably removably mounted to the body 1 of the machine and for this it has a re-entrant shape in the base 2. The drip tray 56 also presents a flange 57 on which is installed the support 11 of cup coffee, support which is in the form of a grid to collect in the same tank 56 possible flows resulting from the infusion of coffee.

In operation, when the coffee reaches the end of the coffee extraction cycle, the user brings the distributor 7 in the rest position so that the hot water flows under pressure which is still in the hydraulic circuit at the output for the block 6 is sent through an expansion pipe 37 to the reservoir 4. in its path, this turbulent hot water flow is broken by the fins 52 of all air jet 50 and is channeled towards an area provided for this effect. This zone can be reservoir 4 when the latter is in place to communicate sealingly with the bore 29 of the funnel 30.

By cons if during the return of the hot water flow to the reservoir 4, the user inadvertently removes the tank 4, where it also slightly raised so that its valve 23 pushed by the spring recall 24 closes the communication of the reservoir 4 with the funnel 30, the return flow will be channeled by the device of the invention to the surrounding area of ​​the funnel 30. This pipe is made through the cut-outs located between the castellations 46 of the plate 45 for a low turbulent jet calmed by the fins 52 of the jet breaker 50. if the flux return or relaxation is not sufficiently held back by all air jet 50, it enters the upper face the plate 45 and the overflow is channeled again by channeling ribs 47 of the plate 45 towards the opening 48 and by the funnel 30. in the funnel 30, overflows arrive by the conduct of 39 evacuation in the recovery tank 56 where they are stored before emptying the bin.

Other embodiments of the invention are possible within the scope of its claims.

Thus, one can imagine that the O-ring 43 is held by a groove formed in the inner wall of bore 29, the transition between the bore 29 and funnel 30 in the absence of the reservoir 4 may be called by a space between the upper edge of the bore 29 and the internal face of the plate 45.

In another variation it is conceivable that the O-ring 43 is held by the column wall 22 of the reservoir 4. It is also conceivable a front seal between the base of the column 22 of the container 4 and a corresponding surface of the connecting device 28.

In yet another alternative, one can consider using other means of expansion, particularly in the form of flexible fins from a peripheral wall installed in the flash pipe or fins installed in the communicating port the flash pipe the tank connection device.