GB2046709A - Apparatus for dispensing a carbonated beverage - Google Patents

Abstract

Apparatus for use in dispensing a carbonated beverage such as a Lager type beer whereby the beverage can be dispensed at a relatively low pressure but stored at a relatively high pressure, the apparatus including a pressure responsive switch (24) communicating with a pipe line (20) and a flow switch (26) in association with reed switches (28 and 30), the arrangement being such that the pump (16) is driven at high power when there is no flow and the pressure switch (24) contacts are closed as a result of the opening of a tap (22), and such that the pump (16) is driven at reduced power when a flow of beverage actuates the flow switch, the closure of the reed switch (30) when the tap (22) is subsequently closed causing the pump (16) to be driven at full power until the pressure switch (24) detects the required storage pressure in the pipe line (20). <IMAGE>

Description

SPECIFICATION Apparatus for dispensing a carbonated beverage.

The invention relates to apparatus for dispensing a carbonated beverage and has for its object to provide an improvement therein.

In particular, the invention is concerned with apparatus for use in dispensing a carbonated beverage, such as beer, from a bulk container, which may be stored in a cellar, by way of a tap or taps at a dispense point in a hotel or bar.

It is common practice to provide an electric motor driven pump for pumping the beverage to the dispense point, control means being provided whereby the pump is started and stopped in response to the opening and closing of the tap or taps at the dispense point. One way in which this can be done is to provide a pressure switch communicating with the pipe line on the output side of the pump to be responsive to changes in pressure of the beverage in said pipe line resulting from opening and closing of the tap, and in this case the arrangement is such that the closure of the pressure switch contacts resulting from a drop of pressure when a tap is opened is effective to start the pump motor and the re-opening of the pressure switch contacts resulting from an increase of pressure when the tap is closed is effective to stop the pump motor.

However, certain kinds of carbonated beverages, in particular the Lager type beers, are difficult to dispense by such known apparatus.

This is because, ideally, they require to be dispensed rather gently, that is to say at a relatively low pressure, but it is advantageous if the pressure in the pipe line when the beverage is not being dispensed can be maintained at a relatively high storage pressure to prevent carbon dioxide coming out of solution. These are of course conflicting requirements, but it is the object of the invention that they should both be achieved in a relatively simple apparatus.

According to the invention, there is provided apparatus for dispensing a carbonated beverage the apparatus including an electric motor driven pump for pumping the beverage to a dispense point; a tap at the dispense point for controlling the discharge of the beverage into a glass or the like; a pressure responsive switch communicating with a pipe line extending between the pump and the tap, said switch having contacts which are caused to open when the pressure of the beverage in the pipe line is raised to a required storage pressure, whereby the switch is responsive to a drop in pressure of the beverage in said pipe line resulting from opening of the tap to effect the starting of the pump as a result of the opening of the tap; first flow detector means for passing an electronic signal to means which thereby cause the pump motor to run at a relatively high power when there is no flow of beverage through the pipe line and the pressure switch contacts are closed; and second flow detector means which are effective, by a flow of the beverage taking place in the pipe line and by the operation of said first flow detector means, to cause the electronic signals to by-pass the pressure responsive switch and to be modified whereby it causes the pump motor to run at reduced power, the arrangement being such that the closure of the tap when the required amount of beverage has been dispensed is effective immediately to stop the flow of beverage through the pipe line but to cause the pump motor to run at a relatively high power until the pressure responsive switch detects the attainment of the required storage pressure in the pipe line. The apparatus will preferably also include an electronic timer, the arrangement being such that the electronic signal which causes the pump motor to run at the relatively high power when the pressure responsive switch detects a drop in pressure of the beverage in the pipe line and the first flow detector means simultaneously detect the absence of flow of beverage through said pipe line, passes through said timer.In this case, the apparatus will preferably include third flow detector means operable, when it detects a flow of the beverage through the pipe line, to remove the electronic signal from the input side of said timer.

A re-set button may be associated with the electronic timer for a purpose which will presently be described. The first flow detector means will preferably be arranged so that, when it detects the absence of flow of beverage through the pipe line, the electronic signal is caused to by-pass means for modulating said signal. The means for modulating said signal will preferably be adjustable so that the pressure of the beverage in the pipe line during a dispensing operation, and thus the rate of flow, can be varied.The flow detector means will preferably each be of the kind including a so-called bobbin or plunger or the like carrying or constituted by a permanent magnet and a so-called reed switch located adjacent the upper or lower end of the flow detector, the state of said switch thus being determined by the degree of proximity of the bobbin or plunger or the like and the position of the latter being determined by the flow or by the absence of flow of the liquid in which it is immersed, the arrangement being such that the bobbin or plunger or the like is lifted by the flow of liquid through or around it or impinging against it and falls back to a lower position when there is no flow. The flow detector means referred to above may share a common bobbin or plunger or the like.On the other hand, if preferred, the flow detector means referred to may be operable by two or even three bobbins or plungers or the like moving independently of each other but reacting, at substantially the same rate of reaction, to the same flow of liquid. The electronic signals for causing the pump motor to run may be applied to a triac or to a relay or to a combination of both in a conventional switching manner to avoid spurious operation of the triac attributable to transients.

In order that the invention may be fully understood and readily carried into effect, the same will now be described, by way of example only, with reference to the accompanying drawings, of which: Fig. 1 is a diagrammatic illustration of a beer dispense apparatus embodying the invention, Fig. 2 is a circuit diagram of an electronic control circuit for the apparatus of Fig. 1, and Fig. 3 is a view similar to Fig. 2 which illustrates a further modification which will be referred to presently.

Referring now to Fig. 1, the beer dispense system there illustrated includes a bulk container 10 to which carbon dioxide under pressure is fed through a pipe 12; a pipe 14 connecting the bulk container to a pump 1 6; and a non-return valve 18 at the outlet side of said pump, that is to say in a pipe line 20 extending from the pump to a tap 22 at a dispense point. The system also includes a pressure responsive switch 24 communicating with the pipe line 20, to be responsive to changes in pressure of the beer in said pipe line resulting from opening and closing of the tap, and a fluid flow detector generally indicated 26 which is disposed in the pipe line 20.The fluid flow detector is of the kind containing a so-called bobbin or plunger or the like (not shown) carrying or constituted by a permanent magnet, and a pair of so-called reed switches (indicated28 and 30 in Fig. 2 and shown chain-dotted in Fig. 1) are located, respectively, adjacent the upper and lower ends of the flow detector so that when there is no flow of beer the bobbin or plunger or the like is at rest in proximity to the reed switch 30, which thus has closed contacts, and so that whenever there is a flow of beer through the flow detector the flow of beer through or around the plunger, or impinging against it, maintains said plunger in a raised condition in proximity to the reed switch 28 which has thus been caused to close.

Referring now to Fig. 2, the pump motor 32 is shown to be electrically connected to a triac 34 which is contained in an electronic control circuit containing the pressure switch 24 and reed switches 28 and 30 referred to above, and a variable speed control unit 36. As shown, the arrangement is such that the reed switch 30, when closed, by-passes the variable speed control unit 36, and the reed switch 28, when closed, bypasses the pressure responsive switch 24.

Assuming now that the appartus is in a condition for the dispensing of beer (and it should be mentioned that in this condition the pipe line 20 is full of beer under a relatively high pressure determined by the setting of the pressure switch, the contacts of which will thus be open, the reed switch 30 is closed and the reed switch 28 is open) the operation of the apparatus is as floows: When the tap is opened to dispense a measure of beer, the closure of the pressure switch contacts resulting from the drop of pressure in the pipe line 20 is effective to start the pump motor and beer starts to flow. At the instant when the pressure switch contacts close, the electronic signal applied to the triac to start the pump motor passes through the reed switch 30 and the pump motor runs at full power to overcome the inertia of the volume of beer in the pipe line.The flow of beer immediately lifts the plunger within the flow detector 26, moving it away from the reed switch 30 and towards the reed switch 28. Consequently, substantially simultaneously, the reed switch 30 opens and the reed switch 28 closes so that the electronic signal no longer passes through the reed switch 30 but passes through the reed switch 28 and through the variable speed control 36.

When this occurs, the electronic signal applied to the triac is modified so that the pump motor then runs at reduced power. In this way, when the tap is opened, the beer in the pipeline is caused to flow with a minimum of delay but as soon as flow has started it continues at a controlled rate determined by the adjustment of the variable speed control 36.

The closure of the tap when the required amount of beer has been dispensed immediately stops the flow of beer through the pipe line 20 and the reed switch 28 opens and the reed switch 30 closes. If the fluid flow detector provided the sole control for rendering the pump inoperative the low power running of the pump motor immediately prior to switch off would result in the pump being stopped before the pressure in the pipe line had risen to the required storage pressure at which the contacts of the pressure switch are caused to open. Consequently, the closure of the reed switch 30, as the bobbin or plunger or the like of the flow detector falls within the now stationary volume of beer in the latter, is arranged to cause the pump motor to run at full power until the pressure responsive switch detects the attainment of the required storage pressure in the pipe line.

Referring now to Fig. 3, the circuit diagram there illustrated is generally similar to that illustrated in Fig. 2 but includes several further components, that is to say an electronic timer 38 and a third fluid flow detector 40, which are connected in series with the pressure responsive switch 24, and a so-called re-set button 42.

The electronic timer 38 is such that an electronic signal can pass through it for a predetermined maximum period of time, following which it closes down until the timer is re-set by 24. This occurs when flow is stopped and the pressure rises. A further signal can then be passed through it for that same maximum period of time.

The reed switch 40 serves to render the timer inoperative when flow is occuring. If a signal has been passed through the timer for a lesser period of time than said predetermined maximum, the timer must be re-set before a further signal is applied. The function of the electronic timer is to protect the pump motor from damage if the pump becomes empty of beer, as follows Assume that the tap is opened after the bulk containers has become exhausted of beer. The pressure responsive switch 24 will detect the fall in pressure of beer in the pipe line 20 and the closure of its contacts will allow the electronic signal to pass through the closed reed switches 30 and 40 and through the timer 38 to the triac 34 so that the pump is driven at full power by the motor 32.However, due to the absence of an available supply of beer in the bulk container, the pump will fail to cause the bobbin or plunger or the like (now shown) of the flow detector to rise so that the reed switches 30 and 40 will remain closed and the reed switch 28 will remain open.

The electronic signal which is causing the pump to run will be removed from the triac as soon as the time delay built into the timer has expired. If the flow of beer stops during a dispensing operation through the supply of beer having become exhausted (that is to say by the plunger (not shown) of the flow detector falling due to lack of flow) the timer operates in like manner to limit the duration of the pumping without load, that is to say limits it to the delay period built into the timer, and it will be understood that during this time the pump is driven at full power in an attempt to reestablish the flow of beer. The predetermined maximum period of time during which the electronic signal can pass through the timer will be a period only slightly longer than that required to dispense, say, one pint of beer under normal operating conditions.

It will be seen that whenever the pressure responsive switch 24 opens fully, that is to say by the required storage pressure being attained in the pipe line 20, the movable contact of said switch makes a further contact and this results in the electronic timer being re-set. It will also be seen that this same function can be achieved, when the pressure responsive switch 24 is closed, that is to say when there is no pressure in the pipe line 20, by operating the re-set button 42. The arrangement is such that when a supply of beer has become exhausted and a fresh supply from another bulk container has been established, the pressure responsive switch will have remained in its closed condition since the commencement of the previous attempt to dispense a measure of beer and the timer will have operated for the predetermined maximum period.Consequently, the timer will need to be re-set by the temporary closure of the re-set button, before a further measure of beer can be dispensed.

It will be seen that the only component parts of the apparatus described above which require adjustment are the variable speed control 36 and the setting of the pressure responsive switch 24.

These are relatively simple to adjust, the adjustments being effected whilst beer is being dispensed, so that a satisfactory flow of beer is obtained. It will be understood that these adjustments are required to suit the flow characteristics of the dispense system, in particular the vertical height through which the beer has to be raised to the dispense point and the kind of beer which is to be dispensed, that is to say, according to how readily the carbon dioxide comes out of solution. Each of the adjustments can be made separately to achieve the two objects of suitable speed of dispense and a required storage pressure throughout the delivery system.

It should perhaps be mentioned that all the required component parts of the apparatus described, including the variable speed control and the electronic timer 38, are commercially available components and that their connection together as illustrated in the drawings will present no problems to those skilled in the art.

Various modifications may be made without departing from the scope of the invention. For example, the timer 38 may be arranged to illuminate a warning sign at the dispense point whenever it operates to stop the pump motor. In this way the barman will know that the equipment.

needs attention.

In each of the two systems described above the flow detector means referred to have been operated by the movement of a single bobbin or plunger within a vertical container. However, it will be understood that they could have been operable by two (or in the case of the apparatus illustrated in Fig. 3 by either two or three) bobbins or plungers or the like moving independently of each other but reacting, at substantially the same rate of reaction, to the same flow of liquid. The socalled bobbin or plunger of a flow detector means may be either a solid substantially cylindrical element (in which case a flow liquid will take place around it) or may be a hollow element (in which case a flow of liquid may take place bo.h through and around it).It will also be understood that instead of incorporating a bobbin or plunger, each flow detector means could include a hinged "flapper" arrangement which is caused to swing by a flow of liquid around it or impinging against it.

Other kinds of fluid flow detectors may of course be employed if preferred. It will be understood that the control unit 36 need not necessarily be a variable speed control unit but could be a plug-in unit of a selected electrical resistance to suit the particular installation, that is to say to give an appropriate speed of dispense. It will also be understood that the various parts of the apparatus may be mounted either in close proximity to each other (for example as a largely self-contained control unit) or separately; in this latter case for example it will be convenient to mount the variable speed control 36 in close proximity to the tap 22 so that the rate of flow from the tap can be adjusted very conveniently.

Claims (9)

CLAIMS:

1. Apparatus for dispensing a carbonated beverage the apparatus including an electric motor driven pump for pumping the beverage to a dispense point; a tap at the dispense point for controlling the discharge of the beverage into a glass or the like; a pressure responsive switch communicating with a pipe line extending between the pump and the tap, said switch having contacts which are caused to open when the pressure of the beverage in the pipe line is raised to a required storage pressure, whereby the switch is responsive to a drop in pressure of the beverage in said pipe line resulting from opening of the tap to effect the starting of the pump as a result of the opening of the tap; first flow detector means for passing an electric signal to means which thereby cause the pump motor to run at a relatively high power when there is no flow of beverage through the pipe line and the pressure switch contacts are closed; and second flow detector means which are effective, by a flow of the beverage taking place in the pipe line and by the operation of said first flow detector means, to cause the electronic signal to by-pass the pressure responsive switch and to be modified whereby it causes the pump motor to run at reduced power, the arrangement being such that the closure of the tap when the required amount of beverage has been dispensed is effective immediately to stop the flow of beverage through the pipe line but to cause the pump motor to run at a relatively high power until the pressure responsive switch detects the attainment of the required storage pressure in the pipe line.

2. Apparatus according to claim 1, including an electronic timer, the arrangement being such that the electronic signal which caused the pump motor to run at the relatively high power when the pressure responsive switch detects a drop in pressure of the beverage in the pipe line and the first flow detector means simultaneously detect the absence of flow of beverage through said pipe line, passes through said timer.

3. Apparatus according to claim 1, including third flow detector means operable, when it detects a flow of the beverage through the pipe line, to remove the electronic signal from the input side of the electronic timer.

4. Apparatus according to either one of claims 2 and 3, including a re-set button associated with the electronic timer.

5. Apparatus according to any one of the preceding claims, in which the first flow detector means is arranged so that, when it detects the absence of flow of beverage through the pipe line, the electronic signal is caused to by-pass means for modulating said signal.

6. Apparatus according to claim Sin which the means for modulating the electronic signal is adjustable so that the pressure of the beverage in the pipe line during a dispensing operation, and thus the rate of flow, can be varied.

7. Apparatus according to any one of the preceding claims, in which the flow detector means are each of the kind including a so-called bobbin or plunger or the like carrying or constituted by a permanent magnet and a socalled reed switch located adjacent the upper or lower end of the flow detector, the state of said switch thus being determined by the degree of proximity of the bobbin or plunger or the like to the reed switch and the position of the bobbin or plunger or the like being determined by the flow or by the absence of flow of the liquid in which it is immersed, the arrangement being such that the bobbin or plunger or the like is lifted by the flow of liquid through or around it or impinging against it and falls back to a lower position when there is no flow.

8. Apparatus according to claim 7, in which the flow detector means share a common bobbin or plunger or the like.

9. Apparatus according to claim 7, in which the flow detector means referred to are operable by two or more bobbins or plungers or the like moving independently of each other but reacting, at substantially the same rate of reaction, to the same flow of liquid.

1 0. Apparatus according to any one of the preceding claims, in which the electronic signals for causing the pump motor to run are applied to a triac or to a relay or to a combination of both in a conventional switching manner to avoid spurious operation of the triac attributable to transients.

1 Apparatus for dispensing a carbonated beverage, constructed, arranged and adapted to operate substantially as hereinbefore described with reference to and as illustrated by the accompanying drawings.