WO2016202655A1

WO2016202655A1 - Beverage dispenser with water nozzle

Info

Publication number: WO2016202655A1
Application number: PCT/EP2016/062941
Authority: WO
Inventors: Olivier Paillard
Original assignee: Nestec S.A.
Priority date: 2015-06-16
Filing date: 2016-06-08
Publication date: 2016-12-22

Abstract

The invention concerns a beverage preparation machine (10) comprising a nozzle (105) for delivering a jet of water in a container (2) and a fluid system for delivering water (4) to the nozzle, said fluid system comprising at least a water supply (101) and a pump (102), wherein the fluid system comprises a damping device (1) configured for progressively increasing the flow of water through the nozzle (105) when water is delivered to the nozzle.

Description

BEVERAGE DISPENSER WITH WATER NOZZLE

Field of the invention

The present invention relates to a beverage preparation machine comprising a nozzle for delivering a jet of water in a container.

Background of the invention

WO 2009/144219 describes a method for producing a frothed whitened beverage with a beverage preparation machine. The method comprises the step of directing a pressurized jet of heated water toward a receptacle comprising milk in order to froth said milk.

It has been noticed that the force of the jet hitting the surface of milk can be quite strong and can throw out splashes of milk around the internal surfaces of the receptacle or even out of the receptacle, particularly at the beginning of the frothing process. This strong jet can also create big bubbles of air at the top of the frothed milk that are not desired.

There is a need for improving the water jet and controlling the force with which it impacts the surface of milk.

Summary of the invention

In a first aspect of the invention, there is provided a beverage preparation machine comprising :

- a nozzle for delivering a jet of water in a container, and

- a fluid system for delivering water to the nozzle, said fluid system comprising at least a water supply and a pump,

wherein the fluid system comprises a damping device configured for progressively increasing the flow of water through the nozzle when water is delivered to the nozzle.

The nozzle of the beverage preparation machine is designed to dispense a jet of water for frothing a beverage present in a container. Generally the nozzle is a simple conduit presenting an outlet end sufficiently small to create a jet of water. While flowing through the outlet end, water reaches a sufficient velocity and therefore a sufficient kinetic energy to provide high shear forces on the surface of the beverage. The outlet end of the conduit can present a section equivalent to the section of circle of a diameter comprised between 0,2 and 1 ,0 mm, preferably between 0,3 and 0,9 mm, even more preferably between 0,4 to 0,6 mm. In a particular embodiment, the nozzle can comprise several conduits. In this latter case, preferably, the sections of the outlet ends present identical value and the sum of the sections presents the same value as the section of a unique conduit outlet end presenting a diameter comprised between 0,2 and 1 mm. Water is delivered by a fluid system comprising a supply of water, generally a water tank, and a pump for pumping water from the supply and delivering it to the nozzle and the beverage container.

The fluid system can comprise a heating device and/or a cooling device to adjust the temperature of water.

The fluid system can comprise a valve to control dispensing of water.

The fluid system comprises a damping device configured for progressively increasing the flow of water through the nozzle when water is delivered to the nozzle.

Accordingly, when the jet of water impacts the surface of the beverage at the beginning of the frothing process, the velocity and the pressure of water at the outlet of the nozzle is more gentle - then there are less or no splashes - and, in a further step, the velocity and the pressure increases to the maximum level to well froth the beverage without increase of splashes.

The damping device in the machine of the present invention enables an increase of the flow of water according to a very rapid slope. Accordingly water does not splash in the cup at the beginning of water dispensing, and very rapidly the highest flow is reached enabling the frothing of the beverage in the cup. As the delivery of water through the nozzle may not last more than few seconds, reaching the highest flow as soon as possible is essential, while avoiding splashing at the beginning.

According to the preferred embodiment, the damping device comprises :

- a chamber, and

- a spring biased plunger movable along the internal walls of the chamber,

the head of the plunger and the internal walls of the chamber defining a variable damping volume,

- an opening for introducing water in the variable damping volume,

the plunger being biased by the spring so that when water is introduced through the opening, the plunger is able to move and increase the size of the variable damping volume.

In the damping device, the head of the plunger and the internal walls of the chamber define a volume, called damping volume. This volume is variable due to the movement of the plunger along the internal walls of the chamber. Usually the head of the plunger is designed to fit exactly along the chamber walls.

When water is dispensed by the pump, it is partially introduced in the variable damping volume. There the pressure exercised by water pushes the plunger and accordingly increases the damping volume. When water is delivered by the fluid system, since at least a part of water delivered pushes the plunger and fills the damping volume, there is less water flowing through the nozzle and water emerges from the nozzle with less velocity.

Progressively, the damping volume does not increase any longer, due to the spring resistance and the velocity of water flow reaches its maximum in the nozzle.

When water delivery is stopped, the spring biased the plunger and moves back the plunger to its original position and the variable damping volume to its original volume.

Preferably the head of the plunger contacts the internal walls of the chamber in a watertight manner. The damping device can comprise a gasket to guarantee watertight contact.

Generally the at least one opening of the chamber of the damping device is connected to the fluid system so as to be positioned downstream to the water supply and the pump and upstream to the nozzle. According to a first mode, the damping device can be connected in the fluid system so that only a part of water delivered by the fluid system to the nozzle is introduced in the inlet opening of the damping device.

Accordingly a part of the water flow is diverted to the damping device whereas the rest is delivered to the nozzle. As long as the part of water diverted to the damping device fills the variable volume chamber of the damping device, the flow of water to the nozzle remains inferior to the maximum flow delivered by the pump and, consequently, the velocity of water flow emerging at the outlet end of the nozzle is lower than if the whole flow of water delivered by the pump is introduced in the nozzle. Once the spring in the damping device cannot be more compressed by the plunger, the variable volume chamber has reached its maximum volume and no more water can be diverted from the main flow. Then the whole flow of pumped water is delivered to the nozzle which can dispense a jet of water at the highest velocity.

Preferably the inlet opening is positioned in the internal wall of the chamber facing the head of the plunger.

According to a second mode, the damping device can be connected in the fluid system so that the whole flow of water delivered by the fluid system to the nozzle is introduced in the inlet opening of the damping device and wherein the damping device comprises an outlet opening for delivering water from the variable damping volume to the nozzle.

Accordingly when water is introduced in the damping device, a part of the water flow fills the variable volume chamber and a part of water is dispensed through the outlet opening to the nozzle. As long as the plunger moves and increases the volume of the variable volume chamber, the flow of water to the nozzle remains inferior to the maximum flow delivered by the pump and, consequently, the velocity of water flow emerging at the outlet end of the nozzle is lower than if the whole flow of water delivered by the pump is introduced in the nozzle. Once the spring in the damping device cannot be more compressed by the plunger, the variable volume chamber has reached its maximum volume and the whole flow of pumped water is delivered to the nozzle through the variable volume chamber and the nozzle can dispense a jet of water at the highest velocity.

The outlet opening is different from the inlet opening. Generally the outlet opening is positioned in a wall of the chamber and is preferably positioned in a lateral wall of the chamber, said lateral wall extending along the axial direction of the plunger.

Preferably the plunger is configured and so that a space is present between the longitudinal lateral walls of the plunger and the internal walls of the chamber, said space extending between the outlet opening and the inlet opening. The plunger can present a transversal section above the outlet opening inferior to the transversal section of the chamber internal volume.

The space between the outlet opening and the inlet opening guarantees that water is dispensed through the nozzle (though with low velocity) as soon as water is pumped.

Preferably the damping device is configured so that :

- the head of the plunger is designed for being able to close the inlet opening when urged against the inlet opening, and

- the plunger is biased by the spring so that at rest the head of the plunger closes the inlet opening.

Accordingly the damping device can act as a back pressure valve in the fluid system delivering water to the nozzle - or to another additional device in the beverage preparation machine - since the fluid system is closed by the damping device when water pumping is stopped. According to a third mode, the nozzle can be a hole extending all along the longitudinal axis of the plunger of the damping device.

In that mode, the nozzle is designed in the plunger of the damping device.

This mode enables a more compact design of the nozzle and the damping device.

Preferably the section of the hole is inferior - at the outlet end - to the section of the opening in the chamber inlet. According to a second aspect, there is provided a nozzle assembly for delivering a liquid in the form of a jet comprising :

- a chamber, and

- a spring biased plunger movable along the internal walls of the chamber,

the head of the plunger and the internal walls of the chamber defining a variable damping volume, said plunger comprising a hole extending all along its longitudinal axis,

- one inlet opening for introducing the liquid in the variable damping volume,

the plunger being biased by the spring so that when water is introduced through the inlet opening, the plunger moves and increases the size of the variable damping volume.

This nozzle assembly can be used in a beverage preparation machine such as described above. It corresponds to the third mode of implementation of the damping device.

According to a third aspect, there is provided a method for frothing a beverage in a beverage preparation machine such as described above, said method comprising the steps of :

- introducing a beverage in a container,

- positioning the container under the nozzle,

- delivering water through the nozzle. Preferably the beverage is milk. Milk may have been introduced in the container by a user it milk may have been previously prepared and dispensed in the container by the machine in a precedent step.

The above aspects of the invention may be combined in any suitable combination. Moreover, various features herein may be combined with one or more of the above aspects to provide combinations other than those specifically illustrated and described. Further objects and advantageous features of the invention will be apparent from the claims, from the detailed description, and annexed drawings. Brief description of the drawings

The characteristics and advantages of the invention will be better understood in relation to the following figures :

- Figure 1 is a schematic representation of a beverage preparation machine according to the first mode of the invention,

- Figure 2 is a longitudinal section view of the damping device used in the machine of Figure 1 ,

- Figure 3 is perspective view of the damping device of Figure 2, - Figure 4 is a schematic representation of a beverage preparation machine according to the second mode to the invention,

- Figure 5 is a longitudinal section view of the damping device used in the machine of Figure 4,

- Figure 6 is a schematic representation of a beverage preparation machine according to the second mode to the invention,

- Figure 7 illustrates the delivery of a jet of water from a damping device according to the third mode of the invention. Detailed description of the drawings

Figure 1 illustrates a beverage preparation machine 10 according to the first mode of the invention. The machine includes a nozzle 105 for delivering a jet of water in a container 2 comprising a beverage 3, preferably milk, and positioned on a drip tray 106.

A fluid system is provided in the machine to be able to feed water in the nozzle, more particularly, hot water. For that, a water tank 101 is provided that can be replenished with fresh water. A water pump 102 transports water from the tank 101 to a water heater 103 such as a thermoblock or a cartridge type heater and to eventually a non-return valve 104. The pump can be any type of pump such as a piston pump, diaphragm pump or a peristaltic pump. The fluid system comprises a damping device 1 upstream the nozzle 105. A pipe 1 10 is derived from the main fluid pipe 109 to deliver a part of the water flow to the damping device 1 .

The machine can comprise a device for preparing the beverage 3 (for example milk prepared from milk powder and water) or an additional beverage in the container 2. This device is illustrated in dotted points and comprises a tank 4 of beverage soluble powder or beverage concentrate, a dosing device 5 for dispensing a dose of powder or concentrate in a mixing chamber 6. The mixing chamber is connected to the fluid system through a valve 7 delivering water either to the nozzle or to the mixing chamber.

Alternatively, the beverage 3 can be introduced by the user within the container (for example fresh milk). Alternatively, the beverage can be produced from a beverage capsule extraction module wherein the beverage is prepared from a capsule comprising a beverage ingredient and in which water is introduced to produce the beverage.

A controller 107 can be further provided to initiate the introduction of water in the container 2 upon the user actuating or being prompted to press a command 108 on the machine.

In a preferred embodiment the outlet end of the conduit in the nozzle 105 can present a section equivalent to the section of circle of a diameter comprised between 0,2 and 1 ,0 mm, preferably between 0,3 and 0,9 mm, even more preferably between 0,4 to 0,6 mm. The delivery of water at a pressure of at least 6 bar in such a nozzle 105 usually enables the production of a jet of sufficient velocity to hit the surface of the beverage in the container 2. The diameter of the nozzle outlet, the pressure of water and the flow rate of water can be adapted according to the desired mixing and/or frothing effect in the container 2. Figure 2 illustrates the damping device 1 of Figure 1 at rest that is when no water is delivered through the nozzle.

The damping device 1 comprises a chamber 1 1 extending along a longitudinal axis XX'. A plunger 13 is positioned within the chamber 1 1 : the plunger extends along the same axis XX' and is movable along said axis. The head 131 of the plunger fits with the internal walls of the chamber so as to define a volume 1 1 1. The chamber comprises an inlet opening 12 for introducing water within the volume 1 1 1 .

The plunger 13 is biased by a spring 14 positioned within the chamber 1 1 and exerting a force to urge the plunger 13 in direction of the inlet opening 12.

The force of the spring is set so that, when water is introduced through the inlet opening 12, water exerts a force against the head 131 of the plunger since there is no other opening in the chamber. Accordingly the plunger can slide along the internal walls of the chamber. The volume 1 1 1 can expand up to a point where the plunger 13 cannot compress the spring 14 anymore. At that point, no more water enters the damping device and the whole flow of water enters the nozzle 105.

Accordingly the damping device enables the by-pass of a part of the water flow directed to the nozzle through said damping device until the variable damping volume has reached its maximum volume. This reduces the force of the jet at the beginning of the water injection and splashes in the container. Figure 3 is a perspective view of the damping device. The chamber is cylindrical.

Figure 4 illustrates a beverage preparation machine 10 according to the second mode of the invention. This machine is similar to the machine of Figure 1 except that the damping device is traversed by the main water fluid pipe 109 so that the whole flow of water enters the damping device. The main water fluid pipe 109 is connected to the inlet opening of the damping device and the nozzle is connected to the outlet opening 15 of the damping device. Moreover the machine does not comprise the non-return valve because the damping device can act as non-return valve as explained later. Figure 5 is a longitudinal section view of the damping device used in the machine of Figure 4 and illustrated at rest position. The damping device 1 comprises a chamber 1 1 extending along a longitudinal axis XX'. A plunger 13 is positioned within the chamber 1 1 : the plunger extends along the same axis XX' and is movable along said axis. The plunger and the chamber are cylindrical.

The chamber comprises an inlet opening 12 in the wall 1 14 of the chamber facing the head 131 of the plunger.

The chamber comprises an outlet opening 15 in a lateral wall 1 13 of the chamber, said lateral wall extending along the axial direction (XX') of the plunger.

The head 131 of the plunger presents a shape designed for cooperating with the shape of the inlet opening 12 in order to close the inlet opening at rest.

A space 1 1 1 is present between the inlet opening 12 and the outlet opening 15 due to the difference of size between the transversal section S_p of the plunger and the transversal section S_c of the chamber. This space defines a variable damping volume as well as a fluid connection between the inlet 12 and the outlet 15.

The force of the spring 14 is set so that, when water is introduced through the inlet opening 12, water exerts a force against the head 131 of the plunger. Accordingly the plunger slides along its longitudinal axis XX' and compresses the spring 1 14. Water enters the volume 1 1 1. A part of water is dispensed through the outlet opening 15 and the rest fills the volume 1 1 1 and moves the plunger. The volume 1 1 1 can expand up to a point where the plunger 13 cannot compress the spring 14 anymore. The whole flow of water is delivered to the nozzle. When the flow of water is stopped, the plunger progressively moves in direction of the inlet opening due to the force exerted by the spring until the head 131 closes the inlet opening 12, which simultaneously closes the main water dispensing line to the nozzle and avoids dripping through the nozzle.

The dampening effect can be set depending on the water pressure delivered by the pump, the design of the nozzle forming the jet of water and the desired slope of increase of the water velocity. The force of the spring, the sections of the chamber and the plunger, the sections of the inlet opening, and optionally the outlet opening, can be adjusted accordingly.

Figure 6 illustrates another beverage preparation machine 10 according to the second mode of the invention. This machine is similar to the machine of Figure 4 except that the damping device is positioned upstream a valve diverting water flow either to the nozzle or to the mixing chamber 6 present in the machine. Apart from its advantage for controlling the strength of the jet delivered by the nozzle, the damping device presents the advantage of acting as a non-return valve when water is dispensed though the mixing chamber. Figure 7 illustrates the delivery of a jet of water from a damping device 1 according to the third mode of the machine of the invention or according to the second aspect of the invention.

The nozzle and the damping device form a single assembly 15 since the nozzle is a conduit 132 extending along the longitudinal axis of the plunger 13.

In step a), water comes in the damping device 15 through the opening 12. Due to the difference of section between the opening 12 and the conduit 132 in the plunger, a part of water fills the conduit 132 and is delivered as a jet at the outlet end of the conduit whereas the rest of water fills the variable damping volume 1 1 1 upstream the head 131 of the plunger.

Step b) illustrates how the variable damping volume 1 1 1 increases due to the introduction of water, pushing the plunger downstream (as illustrated by arrow A) and how the spring 14 is compressed between the head 131 of the plunger and a bottom part 1 12 of the chamber. Due to the division of the water flow between the filling of the variable damping volume and the dispensing through the conduit, the flow of water emerging from the conduit outlet end is not too important and the force of impact of the jet in the beverage is controlled so as to avoid splashes.

Step c) illustrates the moment where the variable damping volume 1 1 1 has reached its maximum size and the spring 14 cannot be compressed more. At this point, the whole flow of water enters the conduit 132 and the force of the jet reaches its highest value ; an efficient frothing of the beverage in the container happens.

Step d) illustrates the moment where water flow is stopped (pump is deactivated). The variable damping volume decreases due to the force exerted by the spring 14 and to water emptying through conduit 132, until there is no more water within the variable damping volume as illustrated in step e).

Consequently during the delivery of water through the assembly, water has been delivered as a jet with a progressively increasing velocity and pressure before reaching a maximum and then progressively decreasing. Due to the reduced force at the beginning splashes in the beverage are reduced.

The objects of the invention present the advantage of delivering the flow of water to the nozzle according to a very rapid slope. It is possible to deliver a jet of water through the nozzle during few seconds, more specifically during 4 seconds, and to avoid the splashing effect because the jet squirts the beverage with less pressure at the beginning of the water delivery. Another advantage of the objects of the invention is that the vibrations and the flow variations usually created by a water solenoid pump - when it is used in the beverage machine - are smoothen due to the fact that the spring in the damping device absorbs the flow variations.

Although the invention has been described with reference to the above illustrated embodiments, it will be appreciated that the invention as claimed is not limited in any way by these illustrated embodiments.

Variations and modifications may be made without departing from the scope of the invention as defined in the claims. Furthermore, where known equivalents exist to specific features, such equivalents are incorporated as if specifically referred in this specification.

As used in this specification, the words "comprises", "comprising", and similar words, are not to be interpreted in an exclusive or exhaustive sense. In other words, they are intended to mean "including, but not limited to".

List of references in the drawings : damping device 1

chamber 1 1

volume 1 1 1

bottom 1 12

lateral wall 1 13

wall 1 14

inlet opening 12

outlet opening 15

plunger 13

head 131

conduit 132

spring 14

beverage machine 10

water supply 101

pump 102

heater 103

valve 104

nozzle 105

drip tray 106 controller 107 command 108 main line 109 secondary line 1 10 container 2 beverage 3 tank 4 dosing device 5 mixing chamber 6 valve 7

Claims

1 . Beverage preparation machine (10) comprising :

- a nozzle (105) for delivering a jet of water in a container (2), and

- a fluid system for delivering water (4) to the nozzle, said fluid system comprising at least a water supply (101 ) and a pump (102),

wherein the fluid system comprises a damping device (1 ) configured for progressively increasing the flow of water through the nozzle (105) when water is delivered to the nozzle.

2. Beverage preparation machine according to Claim 1 wherein the damping device (1 ) comprises :

- a chamber (1 1 ), and

- a spring biased plunger (13) movable along the internal walls of the chamber,

the head (131 ) of the plunger and the internal walls of the chamber defining a variable damping volume (1 1 1 ),

- an inlet opening (12) for introducing water in the variable damping volume (1 1 1 ), the plunger (13) being biased by the spring (14) so that when water is introduced through the inlet opening (12), the plunger (13) is able to move and increase the size of the variable damping volume (1 1 1 ).

3. Beverage preparation machine according to Claim 2, wherein the damping device (1 ) is connected in the fluid system so that only a part of water delivered by the fluid system to the nozzle is introduced in the inlet opening (12) of the damping device.

4. Beverage preparation machine according to Claim 2, wherein the damping device (1 ) is connected in the fluid system so that the whole flow of water delivered by the fluid system to the nozzle is introduced in the inlet opening (12) of the damping device and wherein the damping device (1 ) comprises an outlet opening (15) for delivering water from the variable damping volume (1 1 1 ) to the nozzle.

5. Beverage preparation machine according to Claim 4, wherein the damping device is configured so that :

- the head of the plunger is designed for closing the inlet opening when urged against the inlet opening, and

6. Beverage preparation machine according to any one of the precedent claims, wherein the damping device is connected to the fluid system so as to be positioned downstream to the water supply and the pump and upstream to the nozzle.

7. Beverage preparation machine according to any Claim 2, wherein the nozzle is a hole () extending all along the longitudinal axis (XX') of the plunger.

8. Nozzle assembly (15) for delivering a liquid in the form of a jet comprising :

- a chamber (1 1 ), and

- a spring biased plunger (13) movable along the internal walls of the chamber,

the head of the plunger and the internal walls of the chamber defining a variable damping volume (1 1 1 ), said plunger comprising a hole extending all along the longitudinal axis (XX') of the plunger,

- at least one opening (12) for introducing the liquid in the variable damping volume (1 1 1 ), the plunger (13) being biased by the spring (14) so that when water is introduced through the opening (12), the plunger (13) moves and increases the size of the variable damping volume (1 1 1 ).

9. Method for frothing a beverage in a beverage preparation machine according to any of Claims 1 to 7 comprising the steps of :

- introducing a beverage in a container,

- positioning the container under the nozzle,

- delivering water through the nozzle.

10. Method according to the precedent claim, wherein the beverage is milk.