Beverage Dispenser

Abstract

A refrigerated beverage dispenser having a base and a beverage bowl on the base. A pump in the bowl circulates the beverage in the bowl, and the pump is magnetically driven by a motor in the base. A refrigeration system includes an evaporator within the bowl having a prime surface exposed to the beverage circulated by the pump for cooling the beverage. The condenser and compressor of the refrigeration system are in the base, and a fan driven by the same motor which drives the pump circulates air through the base for cooling the condensor, compressor and motor.

Description

BACKGROUND OF THE INVENTION

This invention relates to beverage dispensers and more particularly comprises a new and improved refrigerated beverage dispenser which is physically smaller than other units now available, requiring a reduced counter area and which nevertheless has the capacity of larger units.

Conventional beverage dispensers employ a forced air mechanical refrigeration condensing unit and a means of circulating the beverage within the dispenser bowl for heat transfer and animation. This equipment has regularly utilized two motors, one for the pump impeller which circulates the beverage and the other for the fan which provides forced air flow over the condensing unit and compressor of the refrigeration system. Two shortcomings of such systems are the added cost imposed by the use of separate motors and the added space required to accommodate both motors.

The evaporators used in conventional equipment are not prime surface evaporators, but rather a plate, either cylindrical or flat, is interposed between the refrigeration tubing of the evaporator and the beverage as the heat exchange surface. Those evaporators require a greater length of refrigeration tubing than prime surface evaporators; they are more costly; and they take up more space in the bowl and/or the base.

The reduction in cost of beverage dispensers is a continuing goal in the industry today. Not only is it required to insure a viable industry, but it is the best method in society's fight against inflation as well. Furthermore, it is essential if our nation is to regain the optimum balance of trade in the international sphere. Thus, one very important object of this invention is to provide a low cost beverage dispenser.

The reduction in physical size is extremely important for all equipment designed for restaurant use. Restaurants, cafeterias, fast food establishments, etc. use an ever increasing amount of food and beverage dispensing equipment, and any saving of space in such establishments is most desirable. Accordingly, another very important object of this invention is to provide a refrigerated beverage dispenser whose physical size is very small as compared to other beverage dispensers now available having comparable volume.

In accordance with the present invention, the beverage dispenser includes a refrigeration system having an evaporator in the bowl and a pump also in the bowl, which causes the beverage to flow in direct heat exchange relationship with the evaporator coils. Thus, a prime surface evaporator is provided for maximum cooling efficiency. Within the base, a single motor serves to drive both the pump in the bowl and a fan in the base. The fan creates a forced air flow through the base to cool the condensor, compressor and motor.

These and other objects and features of the invention will be better understood and appreciated from the following detailed description, read in connection with the accompanying drawings, in which:

BRIEF FIGURE DESCRIPTION

FIG. 1 is a cross-sectional elevation view of a dispenser constructed in accordance with this invention;

FIG. 2 is a cross-sectional elevation view of the base of the dispenser shown in FIG. 1, taken on a plane perpendicular to that of FIG. 1;

FIG. 3 is an enlarged fragmentary view of a portion of the dispenser taken along line 3--3 of FIG. 1; and

FIG. 4 is a cross sectional view taken along section line 4--4 of FIG. 3.

DETAILED DESCRIPTION

The beverage dispenser shown in FIG. 1 includes a base 10, a beverage bowl 12 on the base, a pump 14 in the bowl, a refrigeration system that includes an evaporator 16 in the bowl, and a condensor 18 and compressor 20 in the base. A motor 22 is also mounted in the base which drives both the pump 14 and fan 24.

The base 10 which may be made of metal, plastic, or combinations of such material and preferably is an attractively styled unit suitable for display purposes, has feet 26 designed to support and level the dispenser on a countertop. A drip tray 28 is secured to the front panel 30 of the base and is disposed beneath the beverage discharge spout 32 and actuating handle 34.

Base 10 is divided by a partition 36 into lower and upper chambers 38 and 40. The lower chamber 38 houses condensor 18 and compressor 20. The condensor as shown in FIG. 1 is oriented in a generally vertical plane at the rear of chamber 38 adjacent rear panel 42 which is perforated to allow air to flow into chamber 38 through the condensor as suggested by the arrows 44.

Partition 36 is provided with an opening 46 defined by lip 47, which connects upper and lower chambers 38 and 40. Fan 24 is disposed in opening 46 and when running draws air through rear panel 42 as suggested by arrows 44. Air circulation is through condensor 18, about compressor 20 and desuperheating coils 48, through opening 46 and about motor 22. Side panels 52 and 54 of the base are louvered at the top adjacent the sides of chamber 40 as suggested at 56 (see FIG. 2) to allow the air drawn through the base by fan 24 to be expelled. Thus, the circulating air created by the fan 24 cools the condensor 18, compressor 20, desuperheating coils 48 and motor 22. The several arrows in FIGS. 1 and 2 suggest this air flow path through the base.

Bowl 12 rests on the condensate tray 60 of base 10 and is provided with an opening 62 in its bottom wall 64 through which the plate 66 and evaporator tubing 68 extend. Plate 66 may be secured to the bottom of the condensate tray. Opening 62 has a collar 70 stepped as shown at 71 which surrounds a gasket 72 that forms a seal about plate 66 which extends into bowl 12.

A pair of openings 74 and 76 in plate 66 allow the evaporator tubing 68 to leave and return to the base 10 and connect to the rest of the refrigeration system in base 10. The tubes are appropriately brazed or otherwise sealed in the openings to prevent beverage from leaking through the openings 74 and 76 into the base. As shown in FIGS. 1 and 3, the evaporator tubing is looped or coiled above plate 66 and is contained within a hood 78 generally cylindrical in shape and tapered at the top 80. The hood 78 may be integrally formed with the cover 82 of pump 14, and the two are joined by a passage 84 so that outflow from the pump is directed into and up through the hood 78. The hood in the form shown carries a spray tube 86 that discharges the beverage chilled by the refrigeration tubes 68 against the cover 88 of the bowl so as to provide an animated display.

The bottom of hood 78 fits snugly in the collar 70 of opening 62 in the bottom wall of the bowl. Consequently substantially all of the liquid driven by pump 14 into passage 84 passes upwardly through hood 78 in intimate contact with the refrigeration tubes. Because the flow is channeled through the hood, the beverage travels with a high velocity over the prime surface evaporator so as to promote high heat transfer.

The pump 14 includes a combination driven magnet and impeller 92 disposed in a shallow recess 94 formed in bottom wall 64 of the bowl, and the driven magnet is in close proximity to drive magnet 96 carried on shaft 98 of motor 22. The pump cover 82 integrally formed with hood 78 is provided with inlet ports 100 through which beverage in the bowl 12 enters the pump and is circulated by it through passage 84 and upwardly in hood 78 in intimate contact with the prime surface evaporator 16.

As suggested in FIGS. 1, 3 and 4 one or more solid rods 102 may be disposed inside the evaporator tubing 68 to serve several useful functions in the refrigeration system. First, the tubes reduce the volume of tubing which must be filled with refrigerant. Thus, the charge of refrigerant is reduced, which reduces the cost of the machine and affords a somewhat easier high temperature pull-down. Further, the heat transfer coefficient of the tube is increased by promoting high velocity flow of the refrigerant in the tubing. This is particularly helpful in the downward flow section (which leaves the evaporator tube through port 76) where coefficients are relatively poor as compared to the flow directed upward in the tube entering through port 74. Furthermore, the rod 102 reduces the need for an accumulator at the end of the refrigeration circuit by preventing unevaporated liquid refrigerant from falling out of the downwardly directed tube pass and into the suction line of the refrigeration system. The adverse effects of flooding through on the performance characteristics of small capillary feeding refrigeration systems are well known.

From the foregoing description, the many advantages of this system will be more fully appreciated. As to the arrangement of the refrigeration system and cooling system in the base, the single motor 22 serves to drive both the fan in the base and the pump in the bowl. Because the axes of the pump and fan are aligned with one another, this configuration may be adopted. The single motor reduces the cost as well as the space requirements of the machine.

The machine constructed in accordance with this invention may have a base area of approximately 7 3/4 inches by 10 1/2 inches and has an increased BTU per hour capacity per cubic foot of machine compartment volume.

The use of a continuously operating fan (the motor 22 runs continuously to pump the beverage) of the size used in this application results in a further space savings because of the reduction in size of the single motor used over the single motor needed for the pump only in the prior art devices. When the separate condensing fan motor shuts off in the prior art devices so as to stop ventilation of the pump motor, excessive bearing temperatures result, unless that motor is equipped with an internal fan. This adds to the size of the motor. The continuously operating fan of the present machine which constantly circulates the beverage in the bowl continuously operates the fan to cool the machine.

The use of a single motor is one of the factors in the reduction in the size of the unit. The air flow path through the base is modified and caused to make two right angle turns rather than flow in a straight path through the base as in the prior art devices. The turn in the flow path for the cooling air through the base is made possible by the partition in the base, which divides it into a low pressure inlet chamber (lower chamber 38) and a high pressure chamber (upper chamber 40).

To further reduce the size of the condenser required, and hence the space required, the spacial relationship of the components lends itself to the use of desuperheater coil 48 located above the compressor. Here, in optimum heat transfer relation based on mean effective temperature difference (counterflow), the hot gas loop is located behind the condenser and compressor in the air flow path. Since gas heat transfer inside the tube is low, the secondary surface does not significantly add to the primary surface effectiveness in desuperheating. And a loop or two of prime surface for desuperheating can be added about the top of the compressor without significantly adding space requirements to the machine base.

As for the evaporator, the emersion of the evaporator tubing directly in the beverage eliminates tube contact resistance of tube-in-shell design found in the prior art units.

The high velocity of beverage flow through the hood promotes ice free performance of the dispenser.

The form of the evaporator and hood is every easy to clean as the evaporator tubing is entirely exposed with no hidden areas. And because the hood may readily be removed, it may be washed separately. The construction of the evaporator itself is significantly less costly than the tube-in-shell designs of the prior art. There is a minimum of labor involved in fabrication, and the design peculiarly lends itself to automatic brazing.

The evaporator design, particularly the use of prime surfaces, reduces the tubing requirements by approximately two-thirds as compared to that used in tube-in-shell design. And the high velocity flow over the tubing increases the beverage side transfer co-efficient by a factor of two or three, which further reduces tubing requirements. And the direct expansion in the tubing eliminates the need for secondary surfaces, again reducing material costs.

The construction of the evaporator particularly lends itself to a narrow bowl design. And because the beverage is circulated directly over the evaporator tubing, the evaporator provides effective cooling to the minimum beverage level in the bowl. There is no problem of an exposed dome, as occurs in some of the prior art units when the beverage level drops.

This invention also lends itself to a twin beverage dispenser wherein the evaporator tubing may be looped between the two compartments of the bowl.

Of particular significance is the reduction in the number of components in the machine, which necessarily results in fewer failures in the field. For example, only one motor is employed rather than two or three as in single and twin beverage dispensers of the prior art. Consequently reliability is increased.

Having described this invention in detail, those skilled in the art will appreciate that other modifications may be made of this invention without departing from its spirit. Therefore, it is not intended to limit the breadth of this invention to the single embodiment illustrated and described. Rather, it is intended that the scope of this invention be determined by the appended claims and their equivalents.

Claims

What is claimed is:

1. A refrigerated beverage dispenser comprising

a base and a beverage bowl mounted on the base,

a pump mounted in the bowl for circulating beverage contained therein including a pump cover and an impeller under the cover and a driven magnet attached to the impeller,

a motor in the base, said motor connected to a drive magnet in close proximity to the driven magnet whereby rotation of the motor operates the pump,

a refrigeration system having an evaporator within the bowl for cooling beverage in said bowl circulated by the pump in heat exchange relationship therewith,

a partition in the base dividing it into low and high pressure compartments,

an orifice in the partition,

a condenser and compressor in the base,

an inlet opening in the base for admitting air into the low pressure compartment from outside the base and an outlet opening in the base for discharging air out of the base from the high pressure compartment,

a fan within the orifice creating air flow through the base from the inlet opening through the low to the high pressure compartments and to the outlet opening and free of recirculation within the base for cooling the condenser, compressor and motor, said fan being connected to and driven by the motor,

said evaporator comprising a refrigeration tube connected in circuit with the compressor and condenser,

a readily removable hood enclosing the refrigeration tube in the bowl,

and a passage connecting the pump to the hood causing all the circulation of beverage by the pump to pass through the hood in direct contact with the tube.

2. A refrigerated beverage dispenser as described in claim 1 further characterized by

said fan being an axial flow fan, and said driven magnet, motor and fan being vertically and axially aligned.

3. A refrigerated beverage dispenser as described in claim 1 further characterized by

said condenser being mounted in the base adjacent said inlet opening,

and said motor being mounted in the high pressure compartment and said compressor being mounted in the low pressure compartment downstream of the condenser with respect to the air flow created by the fan whereby the air flow sequentially passes through the condenser, about the compressor and about the motor and avoid recirculation thereof within the base.

4. A refrigerated beverage dispenser as described in claim 3 further characterized by

said fan being an axial flow fan, and said driven magnet, motor and fan being vertically and axially aligned.

5. A refrigerated beverage dispenser as described in claim 4 further characterized by

said base having front, rear and side panels,

said inlet opening being provided in said rear panel and said condenser being positioned immediately in front of said inlet opening,

said compressor being mounted at the bottom of the base in front of the condenser,

and said outlet opening being provided in the side panel.

6. A refrigerated beverage dispenser as described in claim 1 further characterized by

said evaporator having a plurality of generally U-shaped refrigeration tubes,

said hood being generally cylindrical in shape and oriented with its axis vertical and enclosing the tubes and being open at the top,

and said passage being connected to the bottom of the hood whereby the beverage enters the hood bottom and flows upwardly about the tubes and leaves the hood at the top.

7. A refrigerated beverage dispenser comprising a base and beverage bowl mounted on the base, said bowl having top and bottom walls,

a refrigeration system having an evaporator with prime surface refrigeration tubes disposed in and extending generally vertically in the bowl for cooling the beverage therein,

a pump in the bowl for circulating beverage therein with said tubes defining an inverted U-shape,

a readily removable hood mounted generally vertically in the bowl and enclosing the tubes and having an inlet and outlet opening,

and a passage connecting the pump to one of the hood openings causing the circulated beverage to flow through the hood in direct contact with the tubes, said passage being connected to the hood whereby the beverage enters the hood at said inlet opening and flows about and along the tubes and leaves the hood at said outlet opening.

8. A refrigerated beverage dispenser as described in claim 5 further characterized by

said inlet opening in the hood being adjacent the bottom wall of the bowl and said outlet opening being at the top of the hood, said pump being connected to the inlet opening and being disposed outside the hood,

and a spray tube connected to the outlet opening of the hood to produce a fountain-like discharge of the beverage from the outlet opening against the top wall of the bowl.

9. A refrigerated beverage dispenser as described in claim 7 further characterized by

said tubes in shape defining a plurality of inverted U-shaped prime surface refrigeration tubes,

said hood being generally cylindrical in shape and enclosing the tubes and being open at the top,

and said passage being connected to the bottom of the hood whereby the beverage enters the hood bottom and flows upwardly about and along the tubes and leaves the hood at the top.

10. A refrigerated beverage dispenser as described in claim 9 further characterized by

a spray tube connected to the top of the hood for discharging the beverage from the hood adjacent the top of the bowl.

11. A refrigerated beverage dispenser as described in claim 7 further characterized by

said pump including a magnetically driven impeller within the bowl,

and a motor driven magnet in the base in close proximity to the impeller and magnetically coupled thereto to drive the impeller.

12. A refrigerated beverage dispenser comprising

a base and a beverage bowl mounted on the base and having side and bottom walls,

an opening in the bottom wall of the bowl,

a plate mounted on the base and closing the opening when the bowl is mounted on the base,

a refrigeration tube mounted on and leaving and entering the base through the plate,

said tube above the plate describing several generally vertically extending lengths of prime surface evaporator tubing,

a compressor and condenser in the base and forming with the tube a refrigeration system,

a readily removable hood disposed within the bowl on the bottom wall and enclosing the vertically extending lengths of tubing and spaced outwardly from said tubing,

an inlet opening in the hood adjacent the bottom thereof through which beverage in the bowl may enter the hood,

a discharge opening in the hood adjacent the top thereof through which beverage may leave the hood,

and pump means in the bowl operatively associated with the hood causing beverage in the bowl to enter the hood and flow up the hood in heat exchange relation with the tubes and discharging from hood.

13. A beverage dispenser as described in claim 12 further characterized by

said pump means including an impeller and housing,

said housing being integrally connected to said hood at this inlet opening.

14. A beverage dispenser as described in claim 13 further characterized by

said hood being generally cylindrical with its axis disposed vertically in the bowl,

and a collar formed on the bottom wall of the bowl about the opening therein for releasably engaging the hood so that the hood may be readily removed for cleaning and to expose the tubing for cleaning.