CA1325201C - Liquid dispenser - Google Patents

Abstract

ABSTRACT
A dispenser for liquids having an insulated cool chamber to receive a liquid container which has a flexible tube for flow of liquid, a pump in the chamber to pump liquid along the tube, a shut-off valve in the chamber below the pump with an opening for the tube to pass to a dispensing point outside the chamber, a motor outside the chamber for driving the pump, and a gear box connected between the motor and the pump, a revolution counter coupled to the motor, and connected to a counter logic circuit to count each revolution of the motor, and manual controls connected to the shut-off valve and to the motor and to the counter logic circuit so that when the controls are operated the shut-off valve opens within the chamber and the motor is operated for a predetermined number of revolutions, thereby driving and then stopping the pump.

Description

132~201 The invention relates to a dispenser ~or liquid products, and in particular for dairy products such as milk, cream and th~ like, which require refrigeration.
BACKGROUND OF THE INYENTION
Many liquid products are required to bs dispensed in small units. Various beverages, such as dairy products, are frequently pre-packaged in small individual unit sized containers. These are, however, relatively expensive to produce. Empty containers create a disposal problem. Typically, cream used fox tea and coffee and the like, is packaged and dispensed in this waY.
It is, however, well known that such dairy products require to be stored under refrigeration.
Consequently, it is necessary to store such liquid containers in a refrigerated cabinet, and then to maintain a small supply at the point where they are actually used.
This creates added expense and inconvenience.
,, .i ;' Clearly, it is desirable if the liquid products can be packaged in much larger volume containers, stored in a refrigerated cabinet, and dispensed directly from the refrigerated cabinet in unit sized portions as they are i required.
-, BRIEF SUMMARY OF THE INVENTION
~ith a view to solving the various problems noted above, the invention provides a dispenser for , liquids comprising a storage chamber, insulation means enclosing said chamber, heat exchanger means connected with said chamber, and adapted to transfer heat from within said chamber, said chamber being dimensioned and ,~

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adapted to receive a liquid container, having a flexible tube connected to a lower portion thereof, or flow of said liquid from said container, pump means in said chamber, and adapted to receive said tube, and operable to pump said liquid along said tube, shut-off valve means within said chamber and be~ow said pump, opening means in said chamber for said tube to pass to a dispensing point outside said chamber power operated means for operating said shut-off valve means, motor means for driving said pump, and gear box means connected between said motor means and said pump by a motor shaft, said gear box means ~, being connnected to said pump by a gear box shaft, a revolution counter operatively coupled to said motor shaft, and connected to a counter logic circuit, whereby to count each revolution of said motor shaft, and said gear box reducing the speed of revolution between said motor shaft and said gear box shaft, and manual control means mounted on said chamber and connected to said shut-off valve and to said motor means, and to said counter logic circuit, wherebr upon operation of said manual control means, said shut-off valve opens within said insulated chamber and said motor is operated for a predetermined number of revolutions of said motor, thereby driving said pump, within said insulatec chamber, a predetermined number of revolutions less than the number .. of revolutions of said motor, and said counter logic, automatically stopping said motor when said predetermined .. number of motor revolutions is reached.
More particularly, it is an ob~ective of the invention to provide such a dispensing apparatus wherein .

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the pump comprises a peristaltic pump, having at least two roller cams, and a movable housing for receiving said pipe.
More particularly, it is an objective of the invention to provide such a dispensing apparatus and further including a tube mounting bracket, with frictional tube engaging means bet~een said bag and said pump, whereby to prevent said tube being drawn through said pump.
' 10 More particularly, it is an obJective of the invention to provide such a liguid dispensing apparatus, wherein said shut-off valve comprises a single lobe cam mounted on a shaft, and including power operated means for procuring partial rotation of said shaft.
More particularly, it is an objective of the invention to provide such a liquid dispenser wherein said shut-off valve further includes a fixed stop member on one side of said tube, and wherein said single lobe cam is rotatably mounted on the opposite side of said tube, and including a cam backstop msmber, said backstop member being removably mounted, whereby to provide all around access to said cam for cleaning.
More particularly, it is an objective of the .., invention to provide a heat exchanger for use in ~1 association with a refrigerator cabinet, said exchanger ' comprising a thermal electric device, responsive to electrical power to cause a temperature differential thereacross, and a heat exchanger plate portion mounted on the hot side of said thermal electric device, said block portion being formed with a plurality of parallel groovss . . .

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having a tapered cross section, and including a plurality of heat exchanger fins~ each said fin having an edge portion formed with a cross-sectional configuration in the form of a taper matching the taper of said grooves, and wherein the angle of said taper is designed to procure by frictional retention of said tapered edges of said fins in said grooves.
More pa-ticularly, it is an objective of the invention to provide a li~uid dispenser of the general type described, and further including a removable receptacle for receiving said liquid container, said receptacle defining a bottom side and a back wall, and having tube opening means in said bottom wall for passage of said tube therethrough, and having sensing opening means in one of said side walls and said back wall, and temperature sensing means in said cabinet, having a probe portion adapted to enter said sensing opsning, whereby to continuously sense the actual temperature of the contents of said bag.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated and described preferred embodiments of the invention.
IN THE DRAWINGS:
Figure 1 is a front perspective illustration of , .

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a liquid dispenser according to the invention, partially cut-away and showing a bag receptacle partially inserted therein;
Figure 2 is a schematic block diagram of the liquid dispenser of Figure l;
Figure 3 is an enlarged perspective illustration of the shut-off valve;
Figure 4 is an exploded perspective of the shut-off valve;-Figure 5 is a perspective of a holder bracket for the tube;
Figure 6 is a perspective, partially cut-away showing the receptacle for the bag;
Figure 7 is a perspective illustration of the heat exchanger; and, Figure 8 is a section along the line 8-8 of : Figure 7.
~ESC~IPTION OF A SPECIFIC EMBODIMENT
Referring now to Figure 1, the invention will be 1 20seen to be illustrated in the form of a cream dispenser, ..typically for use in self-service restaurants, alongside the beverage station where tea and coffee are dispensed.
, The beverage dispen~er will typically be operated either by restaurant personnel, or else ~ individually by the actual customers.
`.The liquid, in this case cream, will typically :be contained in flexible plastic bags B, provided with ~ elon~ated flexible tubes T, by means of which the contents can be dispensed.
-: 30It will, of course, be appreciated however that ,........... .

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the invention is not limited exclusively to the dispensing of cream, but could equally well be used for di~pensin~ A
.~, ; variety of other liquids or indeed semi-liquid flowable ~`` products such as mayonnaise, ketchup, and other products -` if so desired.
i `.i In order to maintain the entire contents of the ;~ bag, and the tube at a reduced temperature to avoid ..
spoilage, the invention comprises as a principal feature a generally rectangular cabinet indicated generally as 10, :,:
.``' lO \ having side walls 12-12, a top wall 14, and a partial ;~ bottom wall 16, and a rear wall 1~.
A door 20 is provided on the front of the cabinet.
; The side wallsJ top and rear walls and front door are all insulated.
Within the cabinet, a support wall 22 is located, extending from back wall 18 towards the front of the cabinet, but terminating short of the door ~O.
- A partial partition 24 meets the forward edge of the support plate 22. Wall' 22 and partition 24 are both insulated, and the front portion of bottom wall 16 is also insulated, to completely enclose the insulated chamber.
The door 20 is hinged along one side and typically may be secured closed in any suitable manner, for example, by a magnetic gasket or the like, such as is well known in the refrigeration art, which is not shown here for the sake of clarity.
On the other hand, if desired some form of secure fastening means such as a key lock could be provided ~not shown) if vandalism or abuse was a problem.

Within the insulated chamber 10, in the space defined by the partition wall 24, and the partial bottom wall 16, thsre is provided a pump 26. Pump 26 is what is ` known as a peristaltic pump, such as is well known in the ~ pumping art, in particular in relation to the sterile ;~ pumping of fluids in medical and hospital practice. Pumps i of this kind have a removable housing, and two or more cams or lobes. A tube containing a liquid is placed in the housing, around the cams. Operation of the pump causes the lobes or cams to engage the tube and thus force the liquid along the tube in what is usually described as a peristaltic action.
The details of such pumps, which are available from others, are well known in the art, and require no further description.
Also, within, or adjacent to, the partial bottom wall 16 of the chamber 10, there is provided a shut-off valve indicated generally as 28. The shut-off valve 28 is ` located below and to one side of the pump 26, and receives `~ the tube from the pump, and defines the point at which the tube exits the insulated chamber 10.
In Figure 1; the bag is shown in phantom as B, j and the tube is shown in phantom as T.
X A dispensing point D is defined by the lower free end of the tube T.
On the top wall 14 of the chamber 10, there is provided a refrigeration unit indicated generally AS 30.
Refrigeration unit 30 is adapted to extract heat from the interior of chamber 10 and transfer it to the ambiant ; 30 atmosphere, thus maintaining the interior of the chamber i~, .....

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10 at a reduced temperature, to prevent spoilage of the liquid contained in the ba~ B.
Before describing the Yarious components in detail, it will already be appreclated that what the invention now provides is a refrigerated chamber which entirely contains both the bag B, and the tube T through 3 which the liquid is dispensed, and also the pump 26, with the tube T exiting through the shut-off valve 28.
As will be apparent from the following description, once the shut-off valve is closed, and it is always closed while the unit is not in actual use dispensing li~uid, then all of the liquid is contained in a refrigerated chamber, and is therefore protected against spoilage.
Referring now to Figure 2, this illustrates in schematic and block diagrammatic form, a schematic side elevation, partially sectioned, of the liquid dispenser of ~. Figure 1.
^~ Referring first of all to the pump 26 and its associated mechanism, it will be seen that pump 26 is .. driven by means of a gear box output shaft 32 which, in . . .
~: turn, is driven by a gear box 34. Gear box 34 is, in turn, driven by a motor shaft 36, driven by a motor 38.
. The motor 3B is provided with an electrically-operable brake 40, whereby to provide a fast .~! means of halting operation of the motor, for reasons to be described below.
. Also operatively coupled to the motor 38 is a revolution counter 42. Revolution counter 42 is adapted 30 to provide a signal pulse for each revolution of the motor 132~20~

38.
Gear box 34 i5 adapted to provide a substantial reduction in RPM's, typically in the region of between 15 to 1 and 20 to 1 reduction. Thus the shaft 32 will be ~ rotating at only a fraction of the speed of shaft 36.
w As noted---above, pump 26 has a two-part movable housing indicated generally as 44.i The movable housing 44 is constructed so that it may be opened up to receive the tube T, and then closed up again.
As noted, the details of such pump and housing are well known to persons skilled in the art, and are consequently omitted for the sake of clarity.
The counter 42 is connected to counter logic .~ circuit 46 which is, in turn, connected to a control panel 48.
1 Brake 40 is also connected to the control panel .f,~ 48, as is the motor itself.
Referring now to Figures 3 and 4, the shut-off valve is shown in more detail. It will be seen to comprise a support body portion 50, having an abutment 52 extending forwardly on one side thereof.
Opposite the abutment 52, there i~ provided a , swingable cam 54 mounted on a cam shaft 56. Cam shaft 56 ., extends through the body portion 50, and at its inner end, is connected by means of an arm 58 to an actuating device, ` such as a solenoid or the like 60. A return spring 62 will usually be provided to oppose the operation of the ~,; actuating device.
., A cam stop member 64 is removably attached to ~`. 30 the body portion 50 by means of locating pins 66. In this ., .
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way the cam stop member may be removed, so that the cam is free on both sides for cleaning. Actuatin~ device 60 is connected to control panel 48.
It will thus be seen that when the cam 54 is in its vertical position, lying a~ainst the cam backstop 64, the tube T can simply be placed between the cam 54 and the abutment 52.
When the solenoid 60 is oPerated, the cam 54 will rotate through an angle of about 45 degrees, thereby : 10 pinching the tube T and closing it off, at the point where it exits through the insulated partial bottom wall 16.
A door switch 70, typically being a spring-loaded pressure sensitive switch, is mounted typically in one of side walls 12 adjacent the point where the door :. will close.
Closing of the door will operate the switch and opening of the door that will operate the switch in the . other way.
The switch is connected to the control panel 48.
Its function is to cut out the operation of the solenoid ~' 60 so that the cam 54 is returned by the spr~ng to its vertical position. In this way it is possible for an ~ attendant to simply withdraw the tube T, for servicing and cleaning.
~; A set of manual controls, typically being .
~ pressure sensitive button switches indicated generally as `~ 72, are mounted on the front of the door, and are connected to the control panel 48. The buttons may be programmed in various ways. Typically two of the three buttons will be programmed so as to operate the motor 38 ":

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132~2~1 to two different predetermined counts of revolutions of r~ the motor shaft. This will typically correspond to A
single serving of cream and a double serving of cream, in the case where the dispenser i8 used as a cream dispenser.
The third button may be used for continuous run.
This might be u~ed in the ca~e where the dispenser is used for dispensing milk or some other form of beverage.
The electronic circuitry whereby these functions are achieved is well known to persons skilled in the art .. . .
' 10 and requires no description.
A temperature sensor 74 having a probe portion `:' , 76 is mounted on the rear wall 18. Sensor 74 is connected to the control panel 48.
In order to provide for convenient handling of , the flexible bag B, a generally-rectangular open~topped bag receptacle 78 is provided, which may be dimensioned so ~, as to simply slide in and out on the support wall 22. The : receptacle 78 will be provided at its forward end, in its i~
.. , bottom wall with an opening 80, to receive the tube T. In i~ 20 many cases, the bag B and tube T will be provided with a rigid plastic collar indicated as C in Figure 6. In this ~,~ case, the hole 80 may advantageously be provided in a figure 8 fashion, with a larger portion adapted to receive ~'i the collar C, and a smaller portion into which the collar C can be pushed in a locking action, a~ shown in Figure 6.
'.~'.;,! The receptacle 78 also has an opening 82 in one .
.~ of its walls, typically its rear wall as shown in Figure 6. The opening 82 will register with the probe 76. In j., this way the probe 76 can enter through the opening B2 and come into contact with the bag B itself. Thus the ,::
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., ~32~2~1 temperature sensor 74 is at all times sensing the actual temperature of the liquid contents of the bag B.
In order to chill the insulated chamber 10, the heat exchanger unit is provided, whlch is shown in more detail in Figures 7 and 8.
It will be seen to comprise a base or mounting body poxtion 90, which is typically a solid block of metal! which is adapted to be mounted on the top wall 14 of the insulated chamber 10. Top wall 14 is provided with one or more openings 14A and 14B in the insulation, against which the mounting blocks 90 may be set, for maximum heat transfer.
On mounting block 90, there is provided a thermal electric device 92 surrounded by a protective frame 94, and connected by wire 96 to the control panel 48.
` A heat exchange block 98 is mounted on the thermal electric device (TED) 92.
Thermal electric devices are well known in the art, and require no separate description. Upon act~vation by electrical power, they transfer heat, one side becoming hot and the other side becoming cold.
The heat exchange block 98 will thus be mounted on the hot side. Heat exchange block 98 is provided with a large number of spaced parallel grooves 100. As best shown in Figure 8, the grooves 100 have a cross-section in the form of a taper. Typically the taper will be in the region of 3 to 8 degrees. In the case shown, the angle A
of the taper (Figure B) is in fact 5 degrees.
A plurality of heat exchange fins 102 are : -12-` B
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mounted on the block 98. The fins 102 have tapered edges 104. The tapered edges 104 are force-~itted into the tapered grooves 100 in the block 98. The taper angle on the fins matches that of the groove, and thus, by pressure fitting the fins in the grooves a good metal to metal contact i5 achieved, which produces a highly e~ficient form of heat transfer.
In this way it is also possible to provide a very large number of heat exchange plates in a small linear distance across the block 98. In fact, in this way, it is possible to provide in a given length of block 98 as many as double the number of fins, that could be produced if the entire structure were extruded or machined out of a solid block of metal.
It ha~ been found that the operation of the pump 26 may in some circumstances be such as to frictionally engage the tube T and actually draw it through the pump.
:~ In order to prevent this, a tube guide (84) is provided on the upper surface of partial bottom wall 16 adjacent to the pump 26. The bracket 84 (Figure 5) comprises a curved guide portion 85, and two end plates . .
86-86 each having an opening therein to receive the tube.
Leg portions 87-B7 at each end support the bracket 84 on , the bottom wall 16.
The tube T is thus frictionallY fitted into the openings in the two plates 86-86, and is then held secure against movement during operation.
.~ The heat exchanger assembly shown in Figure 7 ~;
may be used by itself, or may simply be used as a modular component in an array of such heat exchanger assemblies.
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1325~ , Thus in Figure 2, two such heat exchanger assemblies are shown, each one having the configuration of Figure 7, and registering with respective uninsulated wall portions 18A
and 18B.
In order to provide efficient heat transfer to atmosphere, any form of blower means such as the fan and motor 106 are provided, being connected to the control panel 48. Typically a sheet metal housing 108 will enclose the heat exchangers and fan 106, and will be provided with louvres 110, at front and back to allow flow of air.
: In operation an operator first of all chills the bag B in a storage refrigerator (not shown). In fact, such bags B will be normally stored in a storage refrigerator or room, and will only be removed as required, and will never be permitted to rise in temperature.
A bag B is then placed in the receptacle 78, . with the tube T passing through the opening 80. -~; 20 The receptacle is then slid on top of the wall 22. The tube T then hangs downwardly, and is passed through the two openings in the plates 86-a6, and is located underneath the curved portion 85.
The tube T is then placed within the housing of the pump, in contact with the roller cams and the housing is then closed.
The tube T is then placed between the cam 54 and - the abutment 52, and the lower end ef the tube T is cut to , , , provide the dispensing point D.
. 30 The door is then closed and the electrical ,...

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circuits then operate. The thermal electric devices commence chilling the interior of the chamber. The ~an commences operating to disburse heat from the heat exchangers. The solenoid 60 is activated so as to close the tube T.
Once the tube T is closed then the lower end can be cut to provide the dispensing point D. Up until this point the tube T has remained sealed to prevent the escape of liquid.
When a person wishes to dispense a portion of the contents of bag B they will simply press one of the three buttons 72. This will then activate motor 38 typically for a predetermined flrst count or a predetermined second count. Typically the first count will be lower than the second count.
As soon as the motor shaft operates, it will `1 ~ then operate the gear shaft at a much slower rate, ... .
typically the ~ear reduction beinOE in the region of between 15 and 20 to 1.
The counter 42 will however count the revolutions of the motor shaft.
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Each complete revolution of the pump 26 may .~;
dispense only a portion of the beverage required.
Consequently if there is a 20 to 1 reduction, and if say ,.,;
`~i four revolutions of the pump are required to dispense a unit portion of beverage, then the motor will be required . .
to turn 80 revolutions.
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As soon as 80 revolutions are counted by the ~: counter 42, the counter logic will then trigger the control panel 48 to signal the brake 40 to close. The ''''.
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, 132~201 brake 40 operates virtually instantaneously, and wiL1 stop the motor 38 in less than one revolution.
This form of control thus provides a very accurate metering of the fluid by the pump 26.
This thus provides precise control over the quantity of fluid dispensed.
This is of considerable importance for two reasons. The operator of the restaurant will have an exact control over the amount of fluid actually dispensed to customers. The customers them~elves will have an exact amount of the fluid dispensed each time. This, in turn, will ensure that the quality and taste of the beverage will be repeatable time after time without variation.
During this time the heat exchangers will wl continue to withdraw heat from the interior of the `i insulated chamber. When a predetermined low temperature is sensed by the sensor 74, then the control panel will ' automatically reduce the electrical power supplied to the thermal electric devices which then operate at a lower level : In this way a form of thermostatic control is provided, giving a highly efficient control over the temperature within the insulated chamber.
The foregoing is a description of a preferred embodiment of the invention which is ~iven here by way of example only. The invention is not to be taken as limited to any of the specific features as described, but comprehends all such variations thereof as come within the scope of the appended claims.
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Claims (8)

1. A dispenser for liquids comprising:
a storage chamber;
insulation means enclosing said chamber;
heat exchanger means connected with said chamber and adapted to transfer heat from within said chamber said chamber being dimensioned and adapted to receive a liquid container, having a flexible tube connected to a lower portion thereof, for flow of said liquid from said container;
pump means in said chamber and adapted to receive said tube and operable to pump said liquid along said tube;
shut-off valve means at an exit point of said chamber and below said pump means;
power-operated means located exteriorly of said chamber for operating said shut-off valve means;
motor means located exteriorly of said chamber for driving said pump means, and gear box means connected to said motor means by a motor shaft, said gear box means being connected to said pump means by a gear box shaft;
a revolution counter operatively coupled to said motor shaft and connected to a counter logic circuit whereby to count each revolution of said motor shaft, said gear box reducing the speed of revolution between said motor shaft and said gear box shaft; and, manual control means mounted on said chamber and connected to said shut-off valve and to said motor means, and to said counter logic circuit, whereby upon operation of said manual control means, said shut-off valve opens at said exit point of said chamber and said motor means is operated for a predetermined number of revolutions of said motor means, thereby driving said pump means within said insulated chamber a predetermined number of revolutions less than the number of revolutions of said motor means, and said counter logic, automatically stopping said motor means when said predetermined number of motor revolutions is reached.

2. A dispenser as claimed in Claim 1, wherein said pump comprises a peristaltic pump, having at least two roller cams, and a movable housing for receiving said tube.

3. A dispenser as claimed in Claim 1, including a tube-mounting bracket, with frictional tube engaging means located between said bag and said pump, whereby to prevent said tube being drawn through said pump.

4. A dispenser as claimed in Claim 1, wherein said shut-off valve comprises a single lobe cam mounted on a shaft, and including power-operated means for procuring partial rotation of said shaft.

5. A dispenser as claimed in Claim 4, wherein said shut-off valve further includes a fixed stop member on one side of said tube, and wherein said single lobe cam is rotatably mounted on the opposite side of said tube, and including a cam backstop member, said backstop member being removably mounted, whereby to provide all-around access to said cam for cleaning.

6. A dispenser as claimed in Claim 1, including a removable receptacle for receiving said liquid container, said receptacle defining a bottom, side walls, and a back wall, and having tube opening means in said bottom wall for passage of said tube therethrough, and including temperature sensing means in said chamber, having a probe portion adapted to continuously sense the actual temperature of the contents of said bag.

7. A dispenser as claimed in Claim 1, wherein said motor means and said valve operating means are located exteriorly of said insulated chamber, and wherein said gear box shaft passes through an insulated wall of said chamber for operation of said pump means within said chamber, and wherein said valve operating means is operatively connected through an insulated wall of said chamber to said shut-off valve.

8. A dispenser as claimed in Claim 1 wherein said heat exchanger includes a thermal electric device responsive to electrical power to cause a temperature differential thereacross having a hot side and a cold side; a heat exchanger plate portion mounted on the hot side of said thermal electric device;
a plurality of parallel grooves formed in said plate portion, each groove having a tapered cross-section; a plurality of heat exchanger fins, an edge portion on each said fin formed with a cross-sectional configuration in the form of a taper matching the taper of said grooves, and wherein the angle of said taper is designed to procure frictional retention of said tapered edges of said fins in said grooves.