GB2345252A

GB2345252A - Mixer for hot drinks beverage dispenser

Info

Publication number: GB2345252A
Application number: GB9915061A
Authority: GB
Inventors: Stefano Gavazzi; Giancarlo Pesenti
Original assignee: Electrolux Zanussi Vending SpA
Current assignee: Electrolux Zanussi Vending SpA
Priority date: 1998-06-30
Filing date: 1999-06-28
Publication date: 2000-07-05
Anticipated expiration: 2019-06-28
Also published as: ES1043595Y; IT1305512B1; DK199900245U3; GB9915061D0; ITPN980048A1; ITPN980048A0; FR2780261B3; DE29907464U1; CH693604A5; ES1043595U; GB2345252B; FR2780261A1

Abstract

A beverage dispenser for hot drinks (eg cocoa or coffee) comprises a mixer space 12 provided with a funnel 5 for feeding powdered ingredients from a superposed container 2 and an injection tube 16 for feeding hot water. The mixer space is arranged above an homogenisation chamber 20, having a motorised impeller, leading to a dispensing outlet 21. The powder feed funnel 5 is produced in one-piece with a box 9 having baffles 17 capable of retaining the more volatile and impalpable fraction of the powdered ingredients which are intercepted by the vapour emitted by the hot water injected into the interior of the mixer space 12.

Description

2345252 IMPROVED MIXER APPARATUS FOR AN AUTOMATIC HOT DRINKS DISPENSER The

present invention concerns a mixer apparatus for mixing raw material in 5 powder form and water of the type used in automatic hot drinks dispensers.

In the context of the present patent the expression raw material is interpreted in its widest meaning and thus includes not only the main ingredient of a drink such as powdered cocoa for preparation of chocolate but also an ingredient which is so-to-speak an auxiliary ingredient such as condensed milk in powder form for the preparation of white coffee.

An apparatus of the kind involved comprises a homogenisation chamber which is open upwardly to receive the ingredients and downwardly to allow the drink to flow away towards the dispensing point. Accommodated within that chamber is at least one rotor or impeller which is actuated by an electric motor at high speed by means of a shaft which passes through a wall of the chamber for the purposes of implementing complete and intimate homogenisation of the raw material and the hot water.

Immediately upstream of the homogenisation chamber the mixer apparatus comprises a mixer space of a funnel-shaped configuration into which the raw material in powder form is fed in a condition of free fall, that is to say in a vertical direction, from a superposed metering container, while the hot water which is produced in an adjacent heater is fed to the mixer space in a tangential direction, that is to say in a direction which is substantially perpendicular to that of the raw material.

During the falling movement of the raw material from the metering container its more volatile and impalpable fraction rises together with the water vapour produced by the hot water and finishes by being disposed at some cold point in the interior of the automatic dispenser.

To guarantee complete homogenisation of the ingredients and thus a high quality for the drink, and in order to operate over a prolonged period without failures, the mixer apparatus would have to be constructed in such a way as not to be subjected to liquid losses. The apparatus would also have to be constructed in such a way that the contamination effects on the part of the above-mentioned more volatile fraction of the raw material are limited to the maximum extent, even if obviously the vapour emitted by the hot water must be freely discharged from the mixer space.

-2 The mixer apparatuses which are currently in use are not entirely satisfactory from the point of view of reliability in operation and they are also designed in a non optimum manner, both from the strictly technical point of view and from the point of view of the costs involved.

The main aim of the invention is to provide an improved mixer apparatus for automatic dispensers which, besides guaranteeing good quality for the hot drinks, can be easily subjected to ordinary maintenance even on the part of people without specific technical competence.

According to the present invention there is provided a mixer apparatus for a raw material in powder form and water which constitute the ingredients of a hot drink prepared in an automatic dispenser, comprising:

a homogenisation chamber with an intake opening for a mixture of the ingredients and an outlet opening for the discharge flow of the drink towards a dispensing point; motorised means for the homogenisation of the mixture of the ingredients within said chamber; a mixer space connected to the homogenisation chamber by way of said intake opening and provided with means for the respective feed of the raw material in powder form coming from a superposed container and the hot water coming from an adjacent heater, in two substantially perpendicular direction, wherein said means for the feed of the raw material are produced in one piece with first means capable of retaining the more volatile and impalpable fraction of the raw material in powder form which is intercepted by the vapour emitted by the hot water injected into the interior of the mixer space.

To permit better understanding of the features and advantages of the present invention a preferred embodiment thereof will be further described by way of non limitative example with reference to the accompanying drawings, in which:

Figure 1 is a simplified overall view of a mixer apparatus in section in a vertical plane; Figure 2 is a view on an enlarged scale of the details enclosed in the square A in Figure 1; and Figure 3 is a view in longitudinal section of a further enlarged scale of just the sealing bush before being mounted on the shaft of the impeller.

Figure I shows, just with the omission of some details which are unrelated to the present invention, a mixer apparatus according to the invention which is generally identified by reference numeral 1, and the superposed container 2 for a raw material in powder form (for example cocoa), which comprises a metering screw (not shown) and a mouth portion 3. The mouth portion 3, except in respect of its outlet, is surrounded by a protective cap 4 which is in turn joined to the container 2. The function of the protective cap 4 is that of recirculating the volatile impalpable fraction of the raw material to the interior of the mixer apparatus, as will be more fully explained hereinafter.

The mixer apparatus I comprises a feeder 5 in the form of a fimel which is open downwardly at 6 and upwardly at 7. The edge of the lateral opening 7 is extended laterally to form a plate 8 which constitutes the slidable cover of a box 9 which has some baffles 17 and a final opening 18 which is connected to the intake of an expeller fan (not shown).

The box 9 is made in one piece with a toroidal jacket 10 which, while remaining circumferentially spaced from the feeder 5, supports the edge of the upper opening 7 thereof. The jacket 10 terminates downwardly at a circumferential edge I I which is turned radially towards the axis of the feeder 54 which rests at the bottom on the circumferential edge of a space 12 having an upper portion 13 of the same shape and section as the toroidal jacket 10 and lower portion 14 of a funnel-shaped configuration, the lower final opening of which is identified by reference numeral 15. The feeder 5 is thus disposed immediately below the mouth portion 3; while the raw material in powder form falls freely from the container 2 by way of the mouth portion 3 and is thus fed to the space 12 in a vertical direction, passing through the openings 6 and 7 of the feeder 5, the hot water (which constitutes the second ingredient of the drink), produced in an adjacent heater (not shown), is fed to the same space 12 by way of an injection tube 16. The final part of the tube 16 is advantageously directed in a tangential direction with respect to the walls of the space 12, that is to say substantially perpendicularly to the direction of falling movement of the raw material - see Figure 1.

Apart from the fact, which is known per se, that the hot water injected by way of the tube 16 entrains therewith the raw material in powder form towards the bottom of the space 12, an important feature of the present invention lies in the fact that the vapour emitted by the hot water intercepts the more volatile and impalpable fraction of the raw material. It is in fact lifted upwardly by virtue also of the slight suction effect which occurs by way of the opening 18 of the cover 8 and by virtue of the meandering path imposed by the divider baffles 17 it is encouraged to become deposited in the interior of the box 9. In turn the protective cap 4, by way of its arrangement, checks everything (volatile fraction of the raw material and or vapour) which however rises from the apparatus and, in accordance with another important feature of the present invention, recirculates it to the interior of the mixer space 12.

As can be better seen from Figure 2, extending below the space 12 and communicating therewith from the above-mentioned final opening 15 thereof is a homogenisation chamber 20 of an elbow-shaped configuration, which terminates towards the bottom with an opening 21 for the discharge flow of the hot drink towards the dispensing point. A wall 22 of the homogenisation chamber 20 is mounted with the interposition of a seal 23 in such a way that it can be separated from the other walls. The separable wall 22 is also fixed to a stationary structure by way of conventional connecting means (not shown).

The above-mentioned separable wall 22 of the homogenisation chamber 20 guides through a suitable opening (not shown) the shaft 26 of an impeller 27 which is actuated by a single-phase asynchronous motor 28 which is supported by means of fixing screws 29 on the stationary structure 24 of the automatic dispenser. As is well known, the function of the impeller 27 is that of homogenising the two ingredients after the mixing effect which has already taken place in the space 12, for the purposes of producing a highquality hot drink. Reference numeral 25 indicates a disc mounted with play on the shaft 26 on the outside of the homogenisation chamber 20, which serves as a retainer for the impeller 27.

In accordance with a feature of the present invention hydraulic sealing integrity of the shaft 26, at the hole provided in the separable wall 22 of the homogenisation chamber 20, is ensured by a bush 30 which is made from an elastic memory synthetic material, for example PTFE HS 110030.

As shown in Figures 2 and 3 the bush 30 is formed by a single member which comprises a shoulder 3 1, a seat 32 for an 0-ring 33, and a very thin circumferential lip 34 which extends from the external face of the shoulder 31 and which, prior to fitting, is of a smaller diameter than the inside diameter of the bush 30.

In view of the elastic memory which characterises the material of which it is made, when the bush 30 is fitted on to the shaft 26 by pushing it in the direction of the arrow F in figure 3, the lip 34 conforms perfectly to the cross-section of the shaft 26 and thus, together with the 0-ring 33, affords perfect hydraulic sealing integrity which will last with the passage of time.

The advantages of the present invention can be summarised as follows:

- The more volatile and impalpable fraction of the raw material in powder form and the vapour produced by the hot water are not going to be deposited at various points in the automatic dispenser (that is what would require the implementation of expensive operations of periodic maintenance, as in the dispensers which are currently in use). In particular the volatile fraction is retained in the box 9 and/or circulated to the interior of the space 12 by the protective cap 4 which extends practically over the feeder 5 apart from around the mouth portion 3; - The reliability in terms of the operation of the mixer apparatus is definitely good, in particular as regards hydraulic sealing integrity around the shaft 26 of the impeller 27, by virtue of the elastic memory material with which the bush 30 is made; and - The entire mixer apparatus is produced with a small number of components, which improves the manufacture thereof, both from the technical and the economic point of view.

Even if the description set forth hereinbefore refers to the preferred embodiment of the invention which provides for the generalised use of plastics materials which are compatible with foods for the production of virtually all the component parts of the mixer apparatus, it will be appreciated as of now that the invention may also be produced in various forms within the scope of the appended claims.

Claims

1. A mixer apparatus for a raw material in powder form and water which constitute the ingredients of a hot drink prepared in an automatic dispenser, comprising:

2. A mixer apparatus according to claim 1, wherein said first means cooperate with a box comprising a toroidal jacket which is circumferentially spaced from said means for the feed of the raw material, supports the edge of the upper opening thereof and terminates downwardly with a circumferential edge supported on said mixer space.

3. A mixer apparatus according to claim 2 wherein said box is provided with an intake opening.

4. A mixer apparatus according to any one of the preceding claims wherein provided around the mouth portion for the passage of the raw material from said container to the mixer space are second means for recirculating to the interior of the mixer space the more volatile and impalpable faction of the raw material in powder form.

5. A mixer apparatus according to any one of the preceding claims wherein the motorised homogenisation means consist of at least one impeller disposed in the interior of the homogenisation chamber and actuated by an electric motor by means of a shaft guided by a wall of the same chamber with the interposition of sealing means, wherein said sealing means comprise a bush produced from a synthetic elastic memory material disposed at the point at which said shaft passes through said wall.

6. A mixer apparatus substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

7. An automatic hot drinks dispensing machine incorporating a mixing 10 apparatus according to any one of the preceding claims.