DESCRIPTION

Field of the invention

The present invention refers in general to devices for dispensing carbonated water, preferably chilled and carbonated water, and has been developed with particular attention being paid to the connection systems used to interconnect certain functional components of such dispensing devices - such as for example a carbonator and a pump - between respective supply sources of water and gas, on the one hand, and members for dispensing water, carbonated water and/or cooled water, on the other hand.

Background art

Dispensing devices of the type indicated, such as those generally known as cooler-carbonators, are appliances designed for connection to a water supply source, such as a domestic drinking water network, and to a source of a pressurised gas, such as a cylinder containing carbon dioxide. These appliances are generally designed to allow to supply water at room temperature, chilled water and carbonated water. Generally, these devices are also designed to carry out a purification or filtration of the incoming water.

In general terms, the most important functional components of a coolercarbonator comprise a pump, a water-cooling system and a water carbonator system, as well as a series of control devices, typically represented by solenoid valves.

The cooling system is usually represented by a classic refrigeration circuit, including a compressor, a condenser with a possible fan, a coil that acts as an evaporator, and an expansion valve or similar lamination member for the refrigerant.

The carbonation system typically comprises a so-called carbonator, i.e., a suitable container in which water and carbon dioxide are mixed, to provide carbonated water at the outlet. Given that a certain pressure is required to obtain the passage of water through the carbonator, the aforementioned pump is also provided. In various solutions, the coil of the refrigeration circuit is in direct contact with the outside of the carbonator, in order to cool the water contained thereinto: hence, in these solutions, the carbonator is exploited both to produce carbonated water and cooled water at the outlet. As mentioned, the cooler-carbonator is supplied with water and carbon dioxide, to allow dispensing of water at room temperature, cooled water and carbonated water, through corresponding dispensing mouths that can be controlled selectively, typically through solenoid valves controlled by suitable keys. This implies that - at least as regards cooled water and carbonated water - the inlets of the cooler-carbonator connected to the water and gas sources must be connected to respective inlets of the carbonator, and that the outlets of the carbonator must be connected to the respective dispensing mouths of the cooler-carbonator.

These connections are traditionally made using flexible hoses, solenoid valves and bulk fitting components, that is, configured as separate components. Given the number of connections required between the water and gas inlets, the inlets and outlets of the carbonator, and the dispensing mouths, it is therefore necessary to prepare and use a lot of flexible hoses, even having different lengths, whose ends must also be equipped with the corresponding connection fittings: this determines the risk of incorrect connections and/or considerable construction times, as well as a significant occupation of space inside the cooler-carbonator. Given that the casing of the cooler-carbonator generally has small dimensions, particularly when intended for free-standing installation in household environments, the arrangement of the pipes is forcibly disordered, and complicates any subsequent maintenance operations, with the aforementioned risk of incorrect connections during production and/or maintenance. The solenoid valves, usually at least four, must be secured to the fixed structure of the coolercarbonator, with further complications in terms of positioning and fixing, and production times. In addition to this, in view of the large number of connections made via bulk fittings, the risk of water leakage also increases correspondingly.

Summary of the invention

In its general terms, the present invention aims to solve one or more of the indicated drawbacks. This aim is attained, according to the invention, by a hydraulic group for a carbonator apparatus having the characteristics indicated in the claims, which constitute an integral part of the teaching provided herein in relation to the invention.

Brief description of the drawings

Further aims, characteristics and advantages of the invention will be clear from the detailed description which follows, made with reference to the attached schematic drawings, wherein: - figures 1 and 2 are schematic perspective views of some components of a carbonator apparatus using a hydraulic unit according to possible embodiments;

- figure 3 is a schematic exploded view of some components of a carbonator apparatus;

- figure 4 is a schematic perspective view of a body of a hydraulic unit according to possible embodiments, with some functional complements represented in exploded way;

- figures 5 and 6 are schematic perspective views, respectively from above and below, of a hydraulic unit in accordance with possible embodiments;

- figure 7 is an exploded view of a hydraulic unit according to possible embodiments forms of implementation;

- figure 8 is a larger- scale detail of Figure 6;

- figure 9 is a first schematic, partial and sectioned, perspective view of a hydraulic unit according to possible embodiments, associated with a carbonator;

- figure 10 is a first schematic section of a hydraulic unit according to possible embodiments, associated with a carbonator;

- figure 11 is a second sectional schematic perspective view of a hydraulic unit according to possible embodiments;

- figure 12 is a third sectional schematic perspective view of a hydraulic unit according to possible embodiments, associated with a carbonator;

- figure 13 is a second schematic section of a hydraulic unit according to possible embodiments, associated with a carbonator;

- figure 14 is a fourth sectional schematic perspective view of a hydraulic unit according to possible embodiments;

- figure 15 is a sixth sectional schematic perspective view of a hydraulic unit according to possible embodiments, associated with a pump and a carbonator with corresponding refrigerating and insulating elements;

- figure 16 is a third schematic section of a hydraulic unit according to possible embodiments, associated with a carbonator;

- figure 17 is a fourth schematic section of a hydraulic unit according to possible embodiments, associated with a pump and a carbonator with corresponding refrigerating and insulating elements;

- figure 18 is a seventh sectional schematic perspective view of a hydraulic unit according to possible embodiments;

- figure 19 is an eighth sectional schematic perspective view of a hydraulic unit according to possible embodiments, associated with a carbonator;

- figure 20 is a fifth schematic section of a hydraulic unit according to possible embodiments, associated with a carbonator;

- figure 21 is a sixth schematic section of a hydraulic unit according to possible embodiments, associated with a carbonator;

- figure 22 is a seventh schematic section of a hydraulic unit according to possible embodiments, associated with a carbonator with corresponding refrigerating and insulating elements;

- figures 23, 24 and 25 are schematic perspectives views of hydraulic units according to possible variant embodiments;

- figures 26 and 27 are schematic perspective views, from different angles, of a hydraulic unit according to further possible embodiments;

- figure 28 is a schematic perspective view of a body of the unit of figures 26-27, with some functional components associated thereto;

- figures 29 and 30 are schematic views, respectively from above and below, of the hydraulic unit of Figures 26-27;

- figure 31 is a schematic section according to line XXX-XXX of figure 30;

- figures 32 and 33 are schematic perspective views, similar to those of figures 1-2, with a hydraulic unit of the type shown in figures 26-31.

Description of embodiments of the invention

Reference to “an embodiment” or “one embodiment” in the framework of this description is intended to indicate that a particular configuration, structure, or characteristic described in relation to the embodiment is comprised in at least one embodiment. Hence, phrases such as “in an embodiment”, “in one embodiment”, or the like that may be present in various points of this description do not necessarily refer to one and the same embodiment. Furthermore, particular conformations, structures, or characteristics defined in the framework of this description may be combined in any adequate way in one or more embodiments, even different from the ones represented. The reference numbers and spatial references (such as “upper”, “lower”, “top”, “bottom”, etc.) used herein are provided merely for convenience and hence do not define the sphere of protection or the scope of the embodiments. In the present description and in the attached claims, the definition "hydraulic unit", referred to the object of the invention, is meant to designate an accessory component for fluidic connection for the carbonator apparatus, in particular intended to be mounted and fixed on a carbonator of said apparatus, but which does not constitute a constructive part thereof. In this perspective, the hydraulic unit described hereinafter does not perform the functions of a sealing lid or closure cap of a carbonator, but is instead intended to be set above such a lid or cap.

In the present description and in the attached claims, the generic term “material” shall be understood as including mixtures, compositions or combinations of several different materials. The same reference numbers are used in the figures to indicate similar or technically equivalent elements.

In figures 1 and 2 there is represented in schematic form a hydraulic unit according to the invention, indicated as a whole with 1, associated with a carbonator apparatus, here represented by a dispenser 2 of chilled and carbonated water, in particular a cooler-carbonator; the dispenser 2 is illustrated only with reference to the components thereof useful for the understanding of the present invention. In the example, the dispenser 2 includes a carbonator 3, a coil 8 for a coolant fluid and an insulation body 9, here generally parallelepiped in shape.

The dispenser further comprises a pump, indicated with 10. In various embodiments, as it can be noted in figure 1, a vertical face of the insulation body, here conventionally defined as the rear face, has associated thereto a metal plate 10c, the pump 10 being fixed to this plate by means of brackets 12.

Referring also to figure 3, the pump 10, of a per se known conception, has a body 10a provided with a head 10b, in which a suction inlet I la and a delivery outlet 11b are defined. The insulation body 9, made for example with a heatinsulating material and/or structure, such as a foamed material, defines a cavity 9a, within which the coil 8 extends, here substantially wound according to a cylindrical helix. The coil 8 acts as an evaporator and belongs, in a known way, to a refrigeration circuit which includes, for example - not represented - a compressor, a condenser with a possible fan, and a possible lamination member for the refrigerant fluid, as well as a possible control circuit.

The carbonator 3 has, in the example, an overall cylindrical shape and is inserted into the helix defined by the coil 8, in contact therewith, in order to enable to cool the water contained in the carbonator: for this reason, the body of the carbonator 3, or at least its peripheral wall, is preferably made of a material having a high heat transfer capacity, for example a metal, such as steel: in the example of implementation described here the carbonator 3 is used both to produce carbonated water, and to produce chilled water, as described below.

At the upper end 3 a of the carbonator 3, here defined at least in part by a wall preferably made of metal, a level probe 4 and a safety valve 5 are mounted, both of conception and operation in themselves known, and therefore not described in detail herein. The level probe 4 has essentially the function of avoiding complete filling of carbonator 3 with water, that is, keeping the upper part of the carbonator free, so as to ensure a gas atmosphere - in particular carbon dioxide - at medium pressure (for example 2-5 bar), for the reasons described below. The safety valve 5 operates instead as a vent, that is, it opens if, for any reason, inside the carbonator 3, a pressure is established above a predetermined safety threshold (for example about 8 bar).

At the upper end 3a of the carbonator 3, i.e., at its upper closing wall, a series of inlets and outlets are defined, and in particular:

- a first inlet 6a, for introduction of water - possibly previously filtered - from a water supply source, for example a domestic drinking water network, not represented;

- a second inlet 6b, for the introduction of a gas from a relevant supply source, such as a carbon dioxide cylinder, not represented,

- a third inlet 6c for pressurized water, that is, water forced by pump 10; - a first output 6d, for the release of chilled water, and

- a second outlet 6e, for the release of carbonated water.

The functions of the aforementioned inlets 6a-6c and the aforementioned outlets 6d-6e will be discussed in detail later.

Preferably, the upper end or wall 3a of the carbonator 3 also defines or has associated thereto elements 7 for the mechanical fastening of group 1, as described below. Such elements may, for example, include shaped metal elements, sealingly inserted into corresponding through openings of the end 3a starting from the lower side thereof, which are provided with a blind hole with a female thread, in order to allow fixing with screws of the unit 1 (see for example figures 13, 15 and 21, where some of the aforementioned fixing screws are indicated with V). In use, the accessory unit 1 is therefore fixed above the upper wall 3a of the carbonator 3.

In figure 4 the main body of the unit is visible, according to possible embodiments, indicated with 20 as a whole, which is in particular a relatively rigid body of polymeric material (without prejudice to a possible limited intrinsic elasticity of the material in question). The polymer body 20 can be formed by injection moulding of at least one polymer; the preferred material is a thermoplastic material, for example PA66 or PPO, possibly filled with glass fibres (for example about 30%). The body 20 is a distinct component with respect to the carbonator 3, and in particular with respect to its upper closing wall having the aforementioned inlets 6a-6c and the aforementioned outlets 6d-6e. The body 20 is prearranged for fixing on the carbonator 3, but it does not constitute a constructive element thereof.

In various embodiments, the body 20 defines a plurality of ducts in a single body. The definition of “single body” is here intended to comprise both the case of a body formed in a single relatively stiff piece, and the case of a body formed by a number of relatively stiff pieces coupled or fixed together, for example welded, or glued, or engaged, or hooked together.

In various embodiments, the body 20 is provided with a plurality of ducts configured for hydraulic connection between the carbonator and the pump of the carbonator apparatus 2.

In various preferential embodiments, the aforesaid ducts comprise at least one duct for supplying water to the carbonator 3, one duct for supplying a gas to the carbonator 3, and at least one duct for withdrawing water from the carbonator 3.

In various embodiments, the body 20 defines or has associated thereto a connection interface, which is configured for connection with the carbonator 3, in particular for fluidic connection at the upper end or wall 3 a of the carbonator, preferably for both fluidic connection and mechanical connection. In various preferential embodiments, the connection interface has at least one water outlet configured for fluidic connection to a water inlet of the carbonator, one gas outlet configured for fluidic connection to a gas inlet of the carbonator 3, and at least one water inlet configured for fluidic connection to a water outlet of the carbonator 3. The aforementioned connection interface is defined at one side of the accessory hydraulic unit 1, here conventionally referred to as “lower side”, which is intended to face and/or rest on the upper surface of the wall 3 a of the carbonator 3.

Preferably, the body 20 also defines a suction outlet configured for fluidic connection with the inlet I la of the pump, and a delivery inlet configured for fluidic connection with the outlet 1 lb of the pump (10). In various preferential embodiments, such as that represented, the body 20 defines in a single piece or body the aforementioned plurality of ducts and the aforementioned connection interface, the latter being indicated as a whole by 30.

The body 20 defines a plurality of inlets and outlets for the aforementioned ducts which, in various embodiments, are selected from the following:

- a first water supply inlet, designed for fluidic connection with the aforementioned water supply source,

- a second gas supply inlet, designed for fluidic connection with the aforementioned gas supply source,

- a water delivery inlet, designed for fluidic connection with the outlet 1 lb of the pump 10,

- a water suction outlet, designed for fluidic connection with the inlet I la of the pump 10,

- a first dispensing outlet for water which is not treated within carbonator 3, i.e., water not cooled and/or water not carbonated,

- a second dispensing outlet, for cooled water, and

- a third dispensing outlet, for carbonated water.

In various embodiments, the first supply inlet has associated thereto a respective valve assembly, which may include at least an impeller of a flow meter, and/or at least one of the first dispensing outlet, the second dispensing outlet and the third dispensing outlet has associated thereto a respective valve assembly. For this purpose, in various embodiments, the body of polymeric material defines, near a longitudinal end of at least one duct of the plurality of ducts, at least one element for the mechanical fastening of a respective valve assembly.

In various embodiments, the water delivery inlet and the water suction outlet generally extend parallel to each other and have respective ends that lie substantially according to one and the same plane. In accordance with other embodiments, the water delivery inlet and the water suction outlet can be differently oriented, for example arranged substantially orthogonal to each other, for example with the aforementioned delivery inlet which is generally parallel to the aforementioned dispensing outlets, and with the aforementioned suction outlet extending upwards, at the upper side of the body 20 of the unit 1.

Referring in particular to the non-limiting example shown in Figure 4, the plurality of ducts comprises:

- a first tubular duct 21, having the aforementioned first supply inlet, indicated with 21 IN, and the aforementioned first dispensing outlet, indicated with 2 lour,

- a second tubular duct 22, having the aforementioned second supply input, indicated by 22IN,

- a third tubular duct 23 for the introduction of pressurized water into the carbonator 3, having the aforementioned delivery inlet, indicated by 23 IN,

- a fourth tubular duct 24, having the aforementioned second dispensing outlet, indicated by 24OUT, susceptible of fluidic connection with the inlet I la of the pump 10, and

- a fifth tubular duct 25, having the aforementioned third dispensing outlet, indicated with 25OUT.

In various embodiments the plurality of ducts also includes a sixth tubular duct 26, having the aforementioned suction outlet, indicated with 26OUT, wherein this sixth tubular duct 26 is in fluid communication with the fourth tubular duct 24.

Preferably, one or more of the first tubular duct 21, the second tubular duct 22, the third tubular duct 23, the fourth tubular duct 24 and the fifth tubular duct 25 extend substantially parallel or side by side, as in the non-limiting example shown, in the longitudinal direction of the unit (i.e., transversely or orthogonally with respect to an axis of the carbonator 3).

It should be noted that the plurality of ducts may include a different number of ducts selected from those exemplified above, for example depending on the functional constructional characteristics of the dispenser.

In various embodiments, at least one duct of the plurality of ducts defines, at one end thereof, a positioning site for a plug. In embodiments of the type exemplified in Figure 4:

- duct 22 defines, at its axial end generally opposite the second supply inlet 22IN, a positioning seat 22a for a 22b plug, and/or

- duct 23 defines, at its axial end generally opposite the delivery inlet 23 IN, a positioning seat 23a for a plug 23b, and/or

- duct 26 defines, at its axial end generally opposite the suction outlet 26OUT, a positioning seat 26a for a plug 26b.

Also in this case, the number of ducts equipped with a plug may vary, for example depending on the functional constructional characteristics of the dispenser. The arrangement of the seats 22a, 23a and the corresponding plugs 22b, 23b may also be different from that exemplified.

Each plug can also be formed with polymeric material, for example injection moulded, and have associated thereto one or more sealing elements, for example ring seals. The plug and its seat can be configured for mutual coupling, for example by means of a bayonet coupling, as in the case exemplified in the figure, or by a thread, or by means of pins.

In various embodiments, one or more ducts defined by the body 20 is/are equipped with at least one non-retum valve. In various preferential embodiments:

- at least one respective non-retum valve is arranged within the gas supply duct, in an intermediate position between the inlet and outlet thereof, which is preferably mounted in a plug occluding said cited duct at an axial end thereof, and/or

- at least one respective non-return valve is arranged within a duct for the introduction of pressurized water into the carbonator, in an intermediate position between an inlet and an outlet thereof, which is preferably be mounted in a plug occluding said duct at an axial end thereof.

Referring to Figure 4, 51 indicates a non-return valve, of a design known per se, which is associated with the plug 22b of the duct 22, for the purposes described below. With 52 and 53 are indicated two additional non-return valves, associated in series with the plug 23b of the duct 23, for the purposes described below.

In various embodiments, the body 20 have associated thereto connecting elements, for connecting the unit 1 to a pump. In various preferential embodiments, the delivery inlet and the suction outlet of the polymeric body have associated thereto respective connection fittings, configured for connection to the outlet and inlet of the pump. Referring to figure 4, with 55a and 55b are indicated two connecting elements, in particular elbow-shaped, designed for coupling with the delivery inlet 23IN of duct 23 and with the suction outlet 26OUT of duct 26, configured for connection to the outlet 11b and the inlet I la of the pump 10, as described below. Fittings 55a and 55b can also me made of a rigid polymeric material.

The delivery inlet and the suction outlet, with the possible associated fittings, obtains an interface arrangement configured for connection with the pump. In other embodiments, the delivery inlet and the suction outlet of unit 1 can be connected to the pump outlet and inlet, respectively, by means of pipes, for example pipes at least partly flexible, as exemplified in the following in relation to possible variants embodiments.

In various preferential embodiments, such as the one exemplified, at least some ducts (in the example ducts 21-25), preferably substantially straight or including substantially straight sections, extend substantially parallel to each other. In various embodiments, a number of ducts extend in one and the same first direction, for example, a longitudinal direction of the body 20 (like ducts 21-25 of the example); one or more additional ducts, if provided, may extend in a second direction, for example a transverse direction with respect to the first direction (such as duct 26).

Preferably, the sixth tubular duct 26 - if it is present - extends in a transverse or angled direction with respect to one or more other ducts of the body 20, such as the ducts 21-25, preferably in a lower position than at least the ducts 22-25.

In various embodiments, duct 26, if present, extends in a transverse or angled direction relative to other ducts of the body 20, such as ducts 21-25. In the non-limiting example shown, duct 26 does not extend below duct 21, as the duct 21 has a reduced longitudinal development, for the purpose of mounting a valve assembly, as explained hereinafter. In order to facilitate the assembly of such valve assembly, without increasing the overall dimensions of the group 1, in various embodiments the duct 21 has two portions 21a and 21b that extend axially at different heights: in the case exemplified, the portion 21a defining the inlet 21 IN extends at a greater height than the portion 21b defining the outlet 2 lour. More in general, in various embodiments, at least one duct of the body 20 has at least one first portion and a second portion that extend axially at different heights.

From Figure 4 it can be seen that, in various embodiments, the dispensing outlet 2 lour, 24OUT and 25OUT are at one and the same first longitudinal end region of the body 20, preferably substantially flush with each other, i.e., with the corresponding ends that lie substantially according to one and the same plane; on the other side, the supply inlet 22IN is at the opposite end region of the body 20, to which also the inlet 21 IN is oriented to.

Preferably, the inlets 21 IN and 22IN, on the one hand, and the outlets 2 lour, 24OUT and 25OUT, on the other hand, extend according to substantially parallel axes, or side by side.

On a preferential basis, the suction outlet 26OUT and the delivery inlet 23 IN are substantially at one and the same end region of the body 20 where the inlet 22IN is located, in order to facilitate connection to the pump 10, as described below. In order to facilitate the connection to the pump 10, the inlet 23 IN and the outlet 26OUT extend preferably generally parallel to each other and have respective ends that lie substantially according to one and the same plane. Preferably, inlet 23IN and outlet 26OUT extend axially in an angled or inclined direction, for example substantially perpendicular, with respect to the direction of extension of the ducts 21-25, at the lower side of the body 20. In any case, as already indicated, the suction outlet 26OUT and the delivery inlet 23 IN can be differently arranged and oriented, in particular in the case of connection to the pump 10 by means of pipes, for example flexible pipes.

In various embodiments, at least one duct of the plurality of ducts defines, in the vicinity of a respective longitudinal end, at least one element for the mechanical fastening of a respective valve assembly, in particular a substantially flange element. In various embodiments, such as the one exemplified in the figures, the tubular duct 21 is shaped to define, near its inlet 21 IN and its outlet 2 lour, respective mechanical fixing elements 50. Similarly, ducts 24 and 25 are shaped to each define, near the respective outlets 24OUT and 25OUT, similar mechanical fixing elements 50. Preferably, the fixing elements 50 have a substantially standard conformation for coupling with commercially available valve assemblies. For this purpose, in the example shown, the elements 50 are generally flange- shaped, and comprise in particular two substantially parallel flanges, to define a groove or engagement seat therebetween for a mechanical fixing member, described below: such a conformation is for example suitable for coupling to solenoid valves as used in the field of household appliances.

In various embodiments, body 20 is shaped to define at least one seat for a sensor or transducer, such as a seat for a pressure transducer. With reference again to figure 4, in the case exemplified such seat - indicated by 46 - is defined at duct 21, in a position intermediate to the inlet 21IN and the outlet 21OUT. In various embodiments, the body 20 is shaped so as to define at least one seat for a flow regulator; in the case exemplified in figure 4, this seat - indicated by 48 - is defined at duct 25, in particular at one of its inlets, as described hereinafter. Preferably each seat 46 and/or 48 is defined at one and the same side of the body 20, for example the upper side, and extends axially in a direction substantially inclined or perpendicular with respect to the direction of extension of other ducts, here the ducts 21-25.

In general, in various embodiments, the body of polymeric material defines at least one of a seat for a pressure transducer and a seat for a flow regulator. Preferably:

- the seat for the pressure transducer is defined along the duct for supplying water to the carbonator (here the duct 21), in an intermediate position between the first supply inlet and the first dispensing outlet, and/or

- the seat for the flow regulator is defined at an inlet for carbonated water defined in the polymer body.

In Figures 5 and 6 the hydraulic unit 1 is shown in different views, with associated respective functional control elements, which comprise a plurality of valve assemblies, and preferably the aforementioned pressure transducer and flow regulator. The various components of the unit 1 are represented in an exploded view in figure 7.

In various embodiments, the first supply inlet 21IN of the body 20 has associated thereto a respective valve assembly. Similarly, at least one of the first dispensing outlet 2 lour, the second dispensing outlet 24OUT and the third dispensing outlet 25OUT has associated thereto a respective valve assembly. In figures 5-7, with 40 is indicated a valve assembly associated with the inlet 21IN, while with 41, 42 and 43 are indicated valve assemblies associated with the outputs 21OUT, 24OUT and 25OUT, respectively.

As is can be noticed, each valve assembly has a respective valve body VB, preferably made of plastic material, having an internal passage that defines a valve inlet IN and a valve outlet OUT. On the valve body VB, in an intermediate position of said passage, an electric actuator is mounted, preferably a solenoid one, with a respective known valve mechanism associated thereto, not visible. Assemblies 41-43 may consist of solenoid valves of a known design, for example of the unbalanced type, widely known in the field of household appliances.

As it can be guessed, particularly from the exploded view of figure 7, the inlets IN of the valve assemblies 41, 42 and 42 are sealingly coupled to the respective outlets 2 lour, 24OUT and 25OUT of the ducts 21, 24 and 25, which are for the purpose preferably provided with seats for respective sealing rings (visible in the figure, but not indicated by reference numerals); similarly, the outlet OUT of the valve assembly 40 is sealingly coupled to the inlet 21 IN of duct 21, also preferably provided with one or more seats for respective sealing rings. As it can be seen, the bodies EV of the assemblies 40-43 are equipped with fixing elements 50 of a type substantially similar to those provided near the ends of the ducts 21, 23 and 25. In this way, the assemblies 40-43 can be coupled to the ends of such ducts 21, 23 and 25 using fixing elements, represented here by interlocking brackets, indicated with 50a, having a generally U-shaped conformation, for bridge-engagement between the elements 50 of the aforementioned ducts 21, 23, 25 and the elements 50 of the aforementioned valve bodies EV. The coupling between the bodies EV of the valve assemblies and the bodies of the ducts could also be of a different type.

In various embodiments, the hydraulic unit 1 is equipped with a flow meter, for example, integrated into one of the valve assemblies. The integration in the unit 1 of such a meter can be useful for the dosage of the amount of water to be dispensed, for example for the purpose of automatic filling of a glass or a carafe or bottle.

In the case exemplified in the figures, such a meter is integrated into the valve assembly 40; in the example, an impeller indicated with 45a in figure 7 is rotatably mounted within the inner duct of the corresponding body EV. According to a well-known technique, the impeller 45a includes an element, for example a magnet, capable of exciting an external detector 45b, for example a magnetic sensor, mounted on the outside of the valve body EV of the assembly 40 in the corresponding position, and having associated thereto a connection wiring 45c. The rotation of the impeller 45a caused by the water in transit determines the periodic passage of the magnet at the detector 45b, which generates at output a number of pulses in the unit of time which is a function of the rotation speed of the same impeller, and hence a function of the water flow rate.

In the exemplified case, the inlet IN of assembly 40 has associated thereto a quick-coupling module 40a, via a ring nut 40b; such a quick-coupling can be of any type, for example of the type known commercially as Speedfit™ (John Guest Ltd). The inlet 22IN can also be configured or equipped with a similar quick coupling, as well as the outlets of the valve assemblies 41, 42 and 43.

In various embodiments, the duct 21 has a comparatively reduced length development with respect to one or more of the other ducts parallel thereto. As indicated, moreover, the duct 21 has two portions 21a and 21b at different heights, i.e., staggered, and does not extend above the duct 26. This conformation can be adopted to enable coupling of the valve assembly 40 to the inlet 21 IN, while reducing the overall dimensions in length and height of the hydraulic unit 1; as can be seen, for example in figures 5-6, in this way the quick coupling 40a associated with the valve assembly 40 is preferably substantially flush with the quick coupling that obtain the inlet 22IN.

From figures 5-6 and 9-10, for example, it is possible to see how the body of the assembly 40 extends above the transverse duct 26, axially aligned with the portion 21a of the duct 21, and how, in order to facilitate this positioning, at least one portion 26c of the transverse duct 26 can have a substantially semi-cylindrical passage section; this portion 26c can also extend below duct 22 (see for example figure 11).

At least one of the ducts 23 and 24 also preferably has at least one respective portion with a similar semi-cylindrical section, but extending in a higher position than the transverse duct 26: in the case exemplified, for example, at least the duct 23 has such a portion, indicated by 23c for example in figures 14, 16 and 18.

Still in figures 5 and 7, with 47 and 49 are visible the previously mentioned pressure transducer and flow regulator, respectively, of a known conception, designed for assembly at the corresponding seats 46 and 48 defined by the body 20; in the example, the transducer 47 is secured in the corresponding seat 46 by means of an appropriate transverse pin 47a (figure 7), while the regulator 48 is screwed in a variable way with respect to a female threading defined in the seat 48. Also in this case, however, the specific fixing elements may vary from the case exemplified.

In various embodiments, the body 20 also defines a plurality of inlets and outlets for fluidic connection with the carbonator 3, selected from the following:

- a water outlet, which is configured for connection to the inlet 6a of the carbonator,

- a gas outlet, which is configured for connection to the inlet 6b of the carbonator,

- a pressurized water outlet, which is configured for connection to the inlet 6c of the carbonator,

- a cooled water inlet, which is configured for connection to the outlet 6d of the carbonator, and

- a carbonated water inlet, which is configured for connection to the outlet 6e of the carbonator. In various embodiments, these inlets and outlets are defined by the previously mentioned interface, which is provided at the lower side of the body 20, i.e., the side intended to be superimposed on wall 3a of the carbonator 3.

The interface is preferably formed in a relatively rigid single piece, but the case is not excluded of a production thereof in a number of relatively rigid parts coupled together to form a respective single body. As mentioned, the body of the hydraulic unit can define in a single piece both a plurality of ducts and the connection interface, but it is also possible to foresee that the ducts, on the one hand, and the interface, on the other hand, are defined by respective single pieces coupled with each other. It is also possible to provide first coupled parts that define the ducts, and second coupled parts that define the interface, with a body formed by the first coupled parts and a body formed by the second coupled parts that are then mutually coupled. It is also possible to provide body parts that define in a single piece both respective ducts, or duct parts, and respective parts of the interface, with these body parts that are then coupled together to form the single body of the hydraulic unit.

In general, the interface is prearranged for enabling a quick and easy connection of the various inlets and outlets of the body of the hydraulic unit with respect to at least corresponding outlets and inlets of the carbonator, preferably through a single operation of mutual coupling.

Preferably, one or more of the water outlet, the gas outlet, the pressurized water outlet, the cooled water inlet and the carbonated water inlet of the connection interface extends substantially angled or perpendicular to a direction of longitudinal extension of one or more from among the first tubular duct, the second tubular duct, the third tubular duct, the fourth tubular duct and the fifth tubular duct.

Referring to the non-limiting example of interface 30 as visible in figure 6, and to the corresponding detail of figure 8:

- the water outlet is indicated with 3 lour, and is in fluid communication with the duct 21 (see also figures 9-10 and 22), in an intermediate position between the inlet 21 IN and the outlet 2 lour;

- the gas outlet is indicated with 32OUT, and is in fluid communication with the duct 22 (see also figures 11-13);

- the pressurized water outlet is indicated with 33OUT, and is in fluid communication with the duct 23 (see also figures 14-16); - the cooled water inlet is indicated with 34IN, and is in fluid communication with the duct 24, herein in an intermediate position between the outlet 24OUT and the inlet I la of the pump 10, herein via the duct 26 (see also figures 18-20 and 22);

- the carbonated water inlet is indicated with 35IN, and is in fluid communication with the duct 25 (see also figures 11, 12, and 21).

In the non-limiting example, the aforementioned outlets 3 lour, 32OUT, 33OUT and the aforementioned inlets 34IN 35IN extend substantially inclined or perpendicular to the direction of longitudinal extension of the ducts 21-25.

In various embodiments, the connection interface 30 is configured for the assembly of the body 20 at the end or wall 3a of the carbonator 3. For this purpose, preferably, the interface 30 includes a plurality of fluidic connections, indicated with 31a, 32a, 33a, 34a and 35a in figure 8, which define the outlets 3 lour, 32OUT, 33OUT and the inlets 34IN and 35IN, respectively. The fluidic connections 31a, 32a, 33a, 34a, 35a each have an interface side - that is, their side oriented towards the end or wall 3 a of the carbonator 3 - which lie preferably substantially according to one and the same plane.

In various embodiments, the fluidic connections of the connection interface each define a respective seat for a gasket, configured to achieve a seal with respect to the end surface or wall 3a of the carbonator 3. Referring in particular to figure 8, the fluidic connections 31a, 32a, 33a, 34a and 35a define annular seats, indicated with 31b, 32b, 33b, 34b and 35b, respectively, suitable for housing corresponding sealing rings, some of which are indicated with 38 in figure 7 (see also figures 11 and 14 for reference). As it can imagined, the rings 38 perform at least an axial sealing function, in particular with respect to the outer surface of the wall 3a of the carbonator 3.

In various embodiments, the body 20 defines a plurality of mechanical connections, configured for the mechanical fixing of the unit 1 to the carbonator 3, in particular at the upper end or wall 3 a thereof. In the example of figure 8, the abovementioned mechanical connections are indicated with 36.

The connections 36 are preferably defined in the connection interface 30. In the example of figure 8, the connections 36 have essentially eyelet conformation, by means of which the interface 30, and therefore the body 20 of the unit 1, can be fixed at the end 3a of the carbonator 3, via the previously mentioned screws V screwed into the threading of elements 7, as shown for example in figures 13, 15 and 21. The mechanical connections 36 also lie preferably according to one and the same plane.

In various embodiments, body 20 defines a plurality of support elements, configured for local rest without mechanical constraints on one or more components of the cooler-carbonator 3.

In the example shown in figure 8, with 37a first support elements are indicated, defined substantially within the interface 30, in positions shifted or offset with respect to the fluidic connections, and designed for resting on the end 3a of the carbonator 3 (see for example figures 9-10).

With reference to figure 6, with 37b second support elements are indicated, spaced apart from the interface 30, configured for local rest on a stationary structure of the cooler-carbonator 3, such structure being here represented by the upper end of the fixing plate 10c of the pump 10 (see for example figure 15). Preferably, the first and/or second support elements 37a, 37b have respective resting ends that lie substantially according to one and the same plane; very preferably, the resting ends of the elements 37a and 37b all lie substantially according to one and the same plane.

Still from figure 8 it is possible to see how, in various preferential embodiments, at least the fluidic connections 31a, 32a, 33a, 34a, 35a are interconnected with each other, and preferably also interconnected with the mechanical connections 36 of the interface 30. In the example, the interconnection is obtained by means of portions or walls 30a of the body 20, such as substantially straight portions, to form a substantially lattice structure. This conformation allows to contain the total weight of the body 20 and the amount of material necessary for manufacturing thereof, while ensuring an adequate structural strength. Possibly, the resting elements can also be interconnected to the fluidic connections and/or mechanical connection through similar straight portions of the body 20.

In figures 9 and 10 it is clearly visible how, preferably, the outlet 3 lour of the fluidic connection 31a is defined in an intermediate position of the duct 21, for the connection with the corresponding inlet 6a of the carbonator 3, having associated thereto a duct WIN for supplying water to the carbonator 3.

In the non-limiting example represented in the figures, the internal volume of the carbonator 3 is divided into two sections or compartments by an intermediate transverse wall, indicated in the figures with 3b. The lower compartment, indicated with A, is basically intended for the production and accumulation of cooled water, while the upper compartment, indicated with B, is intended to ensure presence within it of an atmosphere of gas under a slight pressure, that is, carbon dioxide in the example considered here. The above- mentioned duct WIN, which passes through the intermediate wall 3b and extends until close to the bottom of compartment A (see also figure 22), is therefore intended to adduce to the compartment A water coming from the inlet 21 IN, for the purposes of cooling this water.

In figures 11-13 it is visible how the outlet 32OUT of the fluidic connection 32a of the connection interface is connected to the inlet 6b of the carbonator 3, this inlet 6b opening in the upper compartment B . From these figures it may also be noted that the non-return valve 51, here associated, or close, to the cap 22b, is located within the duct 22 in an intermediate position between its inlet 22IN and outlet 32OUT. In this way, as can be imagined, within carbon dioxide can be retained at a certain pressure within the compartment B.

In figures 14-16 there are visible the outlet 33 OUT of the fluidic connection 33a of the connection interface, designed for connection with the inlet 6c of the carbonator 3, as well as - also in figure 17 - the inlet 23 IN of the duct 23, designed for connection with the outlet 1 lb of the pump 10 (see in particular figures 15 and 17), through the corresponding fitting 55b. The inlet 6c also opens in the compartment B of the carbonator 3, and essentially consists of a calibrated hole (with a diameter approximately between 0.8 and 1.2 mm), for the forced entry of water into the carbonator. In particular, from figures 15 and 16 it is possible to notice how, in front of the entrance 6c, at a certain distance therefrom inside the compartment B, there is preferably positioned a portion of a deflector element DE, here substantially L-shaped, in such a way that pressurized water entering through the inlet 6c hits this portion of the deflector DE, for the reasons explained hereinafter.

From figures 14-16 it is well noted how the non-retum valves 52 and 53, here associated, or close, to the plug 23b, are located within the duct 22 in an intermediate position between the inlet 23IN and outlet 33OUT thereof. In this way, as it can be imagined, valves 52 and 53 also prevent the outflow from compartment B of the carbon dioxide contained thereinto.

In figures 18-20 it is visible the inlet 34IN of the fluidic connection 34a of the connection interface, designed for connection with the inlet 6d of the carbonator 3, to which a duct CWOUT is associated, for withdrawing cooled water from the carbonator 3, in particular from compartment A. For this purpose, the aforementioned duct CWOUT passes through the intermediate wall 3b and extends slightly beyond it, at the upper part of compartment A (see also figure 22). In figure 18 is also visible the duct 26, with its outlet 26OUT, designed for connection with the inlet I la of the pump 10 (see also figure 17), through the corresponding fitting 55a.

From figure 18 it is clear how, in the shown example of implementation, the duct 24 and the duct 26 are connected to each other, in the area indicated by C, and how the inlet 34IN is located along the duct 24 in a position intermediate to the delivery outlet 24OUT and this connection area C between the ducts 24 and 26.

Still in figures 11-12 and figure 21 there is visible the inlet 35IN of the fluidic connection 35a of the connection interface, designed for connection with the outlet 6e of the carbonator 3, to which a duct is associated, for the withdrawal of carbonated water SWOUT from the carbonator 3, particularly from compartment B. For this purpose, the aforementioned duct SWOUT extends within the compartment B at a lower height than the portion of the deflector element DE that is opposite to the inlet 6C (see also figure 15).

From figures 11, 12 and 21 it can be seen how the inlet 35IN is defined substantially in a position corresponding to the end of the duct 25 which is opposite to the outlet 25OUT, and how the flow regulator 49, i.e., its regulating tip, is located right at the inlet 35IN, in order to allow prior adjustment of its passage section (screwing more or less the regulator 49 in the corresponding threaded seat 48).

The valve assemblies 40-43 are of a normally-closed type and are opened depending on the water withdrawals made by a user of the cooler-carbonator, by operating on respective control elements, for example keys present on a user interface (not represented) of the cooler-carbonator.

When the user wants the supply of water at room temperature, he operates a first key, thereby determining opening of the valve assembly 41 associated with the outlet 2 lour of the duct 21: in this way a decrease in pressure inside the duct 21 takes place, detected by means of the pressure transducer 47, which consequently controls opening of the valve assembly 40 associated with the inlet 21IN of the same duct 21: in this way, passage of water from the inlet IN of the valve assembly 40 to the outlet OUT of the valve assembly 41 is allowed. When the user wants the dispensing of cooled water, he operates a second key, thereby determining opening of the valve assembly 40 associated with the inlet 21 IN of duct 21 and the opening of the valve assembly 42 associated with the outlet 24OUT of duct 24. In this way, referring for example to figure 19, mains water at room temperature can flow into the compartment A of the carbonator, through the duct 21, the outlet 3 lour and the duct WIN associated with the inlet 6a of the carbonator, and a corresponding volume of chilled water is forced to flow out of this compartment A, through the duct CWOUT associated with the outlet 6d of the carbonator 3 and the inlet 34IN: the cooled water is then dispensed through the outlet OUT of the valve assembly 42.

When the user wants the dispensing of carbonated water, he operates a third key, thereby determining opening of the valve assembly 43 associated to the outlet 25OUT of the duct 25, and activation of the pump 10. Pump 10 (see for example figures 12, and 17-19) sucks at the inlet 11th thereof cooled water from compartment A of the carbonator 3, via the duct CWOUT, the inlet 34IN, the ducts 24 and 26, and the outlet 26OUT. This chilled water is then forced at the outlet 1 lb of the pump 10, to reach the outlet 33OUT and hence penetrate the compartment B of the carbonator 3, through the inlet 6c (see for example figure 15), after passing the non-retum valves 52-53. Therefore, the water forced by the pump is under pressure (for example between 8 and 10 bar, greater than that of the carbon dioxide atmosphere present in compartment B), and penetrates with high energy the calibrated inlet 6c of the carbonator 3, substantially nebulizing and hitting with force the corresponding opposite portion of the deflector element DE: in this way, the nebulized water particles aggregate to the carbon dioxide present in the compartment B, and then flow through the duct SWOUT associated with the outlet 6e of the carbonator, i.e., at the inlet 35IN of the hydraulic unit 1, through the flow regulator 49; the carbonated water can then flow into duct 25 to be dispensed through the outlet OUT of the valve assembly 43.

The level probe 4 of the carbonator 3 has a detection part 4a (see for example figures 13 and 16), in order to prevent the compartment B from being complete filled with water, that is, to keep the upper part free for the carbon dioxide. The safety valve 5 of the carbonator 3 (see e.g., figure 15) prevents potentially dangerous pressures from being established inside the carbonator 3.

In the embodiments previously exemplified, the hydraulic unit according to the invention is equipped with a plurality of electrically controllable valve assemblies. However, this is not an essential feature, since in possible variants embodiments, the hydraulic unit could be designed for use on cooler-carbonators provided, for example, with taps that are manually operable by the user. In this perspective, one or more ducts of the body 20 could have a modified shape, also at their inlets and/or outlets.

For example, figure 23 illustrates the case of a unit 1 in which the ducts 21, 24 and 25 of the body 20 have a modified shape, where in particular each of them has a respective terminal portion 211, 24i and 25i, without valve assemblies directly associated thereto, which defines a relative attachment, preferably of a quick type, not visible, but for example similar to the quick coupling of the inlet 22IN with its ring nut 40b, or equipped with a module of the type previously indicated with 40a (see figure 7). In such a case, therefore, the outlets 21OUT, 24OUT and 25OUT of the body 20 are obtained by such quick couplings. Figure 24 illustrates the case of a body 20 whose duct 21 has a respective initial portion 2h without a directly associated valve assembly, which defines such an attachment, preferably of the quick type; in such a case, therefore, the inlet 21 IN of body 20 is obtained by such an attachment.

Note that, in figures 23 and 24, the ducts 21, 24 and 25 are provided with flange elements F of the type previously indicated with 50, near which the ducts themselves define grooves or restrictions R (the aforementioned flange elements F and the aforementioned restrictions R are indicated in figures 23-24 only for duct 21). This configuration can be useful to obtain a single version of the body 20 by moulding, which can be used as shown in figures 23-24, or which can instead be modified by mechanically removing the portions of the duct downstream of the aforementioned restrictions R, in order to obtain useful space for the coupling of valve assemblies of the type previously indicated with 41, 42 and 43; in this case the restrictions R realize the hydraulic connections for the valve groups and the seats for the corresponding sealing rings, while the elements F are used for the mechanical fixing of such valve assemblies, for example using brackets of the type previously indicated with 50a.

A body 20 substantially of the type described with reference to figures 4-6 can also have associated thereto one or more extension elements, to obtain configurations without one or more valve assemblies as exemplified in figures 23 and 24. For example, figure 25 shows a case similar to that of figure 24, in which a body 20 have associated thereto extension elements indicated with 61, each having a tubular body of plastic material which defines the respective inlet and outlet.

In the example, an extension element 61 has an inlet 61IN, for example configured with a quick coupling, and an outlet 6 lour that is shaped for sealed coupling with the inlet 21 IN (not visible here) of the duct 21. Similarly, three further extension elements 61 have respective inlets 61 IN shaped for sealed coupling with the outlets 2 lour, 24OUT and 25OUT of the ducts 21, 24 and 24 (not visible here), and respective outlets 6 lour, for example configured with a quick coupling. In the example, the extension elements 61 integrally define - near the respective inlets or outlets for fluidic connection with the body 20 - mechanical fixing elements of the type already indicated with 50, in order to enable the parts 20 and 61 to be secured to each other by means of fixing members of the type previously indicated with 50a.

In figures 26-31 there is represented in a schematic form a hydraulic unit 1 in accordance with further possible embodiments. In these figures the same reference numbers as the previous figures are used, to indicate elements technically equivalent to those already described above. Also this hydraulic unit 1 has a respective body 20 made of plastic material, configured for mounting on a carbonator, in particular at its end or upper wall equipped with inlets and outlets.

With respect to the embodiments mentioned above, unit 1 of figures 26-31 is distinguished by a more compact body 20, and configured for connection to the pump of a carbonator apparatus by means of pipes, preferably at least partly flexible pipes. Note that what has been described above in relation to these carbonator apparatus and pump is equally valid in the case of the unit 1 of figures 26-31. Unit 1 of figures 26-31 includes the various components and ducts already described above, which are simply redistributed, while ensuring the same functionalities already indicated for the unit 1 of figures 1-25, in particular in terms of fluidic connection to the carbonator and the pump.

Unit 1 of figures 26-31 is particularly prearranged for connection to a pump by means of pipes, preferably flexible pipes. For this reason, as compared to the versions of hydraulic unit 1 referred to in figures 1-25, unit 1 of figures 26-31 does not require the duct 26 in which the suction output 26OUT is to be defined, and the ducts 22 and 23 can have a respective comparatively smaller axial development, also compared to the ducts 21, 24 and 25, as can be seen for example in figures 29-30; on the other hand, the duct 25 may have a longer development than in the case of unit 1 of figures 1-25.

The delivery inlet 23IN and the suction outlet 26OUT of unit 1 of figures 26- 31 can also be differently positioned. Referring for example to figure 29, it will be noted that the suction outlet 26OUT can in this case be defined directly at the duct 24, in particular at the upper side thereof, and how the delivery inlet 23 IN can be oriented towards the outlet end of unit 1 (i.e., the end equipped with the valve assemblies 41-43). As can be seen, therefore, the delivery inlet 23IN and the suction outlet 26OUT are located in a generally central region of unit 1, or in respective positions of the body 20 that are intermediate to the two longitudinal ends of the body itself.

Given the different conformation and arrangement of ducts 22 and 23, the seats 22a, 23a and the corresponding plugs 22b, 23b can also be arranged differently with respect to the case of figures 1-25. Also in the case of figures 26- 31 the seats 22a, 23a are defined substantially in a position corresponding to an axial end of the duct 22, 23, respectively, opposite to the corresponding inlet. In the case of figures 26-31, however, although they are still in fluid communication with the ducts 22 and 23, the seats 22a and 23 a extend vertically at the upper side of unit 1 or body 20, as clearly visible for example in figures 26, 27 and 31, and without prejudice to their functions of housing the non-return valves 51 and 52- 53, which are associated to the plugs 22b and 23b, respectively, as clearly visible for example in figure 31. From the same figure 31 it is noted that, in embodiments of this type, the gas outlet 32OUT and the pressurized water outlet 33OUT can be defined at the bottom of the same seats 22a and 23a, respectively.

The features and functionalities described above for the connection interface 30 remain valid in the case of the unit 1 of figures 26-31, as can be seen for example from Figure 30. From this figure it can be noticed that the arrangement of the outlets 3 lour, 32OUT, 33OUT and the inlets 34IN, 35IN of the interface 30 may be different from the one exemplified in figure 8, for example in view of a different arrangement of the inlets 6a-6c and the outlets 6d-6e of the carbonator (see figure 3 as a reference).

Figures 32 and 33 illustrate a mounted condition of unit 1 of figures 26-31 on a carbonator 3 of a dispenser 2 of the type already indicated above, equipped with a corresponding pump 10.

In this case, the pump 10 is located on the insulation body 9 of the dispenser 2 at the outlet end of group 1, i.e., the end thereof including the valve assemblies 41-43, although this is not an essential feature. From these figures it is also possible to notice the fluidic connection of the pump 10 to the unit 1 by means of pipes, indicated with T1 and T2, preferably at least partly flexible pipes.

As particularly visible in figure 32, the pipe T1 connects the outlet 11b of the pump 10 to the delivery inlet 23 IN of the unit 1, while the pipe T2 connects the input 1 la of the pump 10 to the suction outlet 26OUT of the unit 1. In the example, the connection of the pipes T1 and T2 to the outlet and inlet of the pump 10 is achieved using quick-coupling fittings, for example of the type previously indicated with 55b and 55a, respectively, although this does not constitute an essential characteristic; a similar fitting, such as the one indicated with 55c, can be used for the connection of the pipe T2 to the outlet 26OUT of group 1. A similar fitting could possibly also be used for the connection of the pipe T1 to the inlet 23IN of unit 1.

The functionalities of the unit 1 of figures 26-31 are the same as those described above with reference to the embodiments of figures 1-25.

Also in the case of the embodiments of figures 26-31, the hydraulic unit 1 could be designed for use on cooler-carbonators equipped, for example, with taps that can be manually operable by the user. In this perspective, one or more ducts 21, 24 and 25 of the body 20 of unit 1 could have a modified shape, also at the corresponding inlets and/or outlets, similarly to what has been described above with reference to figures 23 and 24. In the same way, also the body 20 of unit 1 of figures 26-31 could have associated thereto one or more extension elements, to obtain configurations without one or more valve assemblies, similarly to what has been described above with reference to figure 25.

Presence of the pressure transducer 47 and/or the flow meter 45a-45c shall be considered optional in all embodiments.

It is clear that numerous variants are possible for the person skilled in the art to the hydraulic unit described as an example, without departing from the scope of the invention as defined by the claims that follow.