EP0488586A2

EP0488586A2 - Carbonation system

Info

Publication number: EP0488586A2
Application number: EP91310731A
Authority: EP
Inventors: Joseph W. Shannon; Thomas S. Green
Original assignee: ABC/TECHCORP Inc
Current assignee: ABC/TECHCORP Inc
Priority date: 1990-11-27
Filing date: 1991-11-21
Publication date: 1992-06-03
Also published as: EP0488586A3; JPH06114251A

Abstract

A carbonation system (10) is provided in which replenishment or recharging of the carbonation tank (12) is undertaken upon the basis of sensing and monitoring the CO₂ gas head pressure within the tank. No floats or liquid level sensors are employed. A pressure switch (40), monitoring the head pressure within the tank, is operative to turn a high pressure motor (26) on and off to appropriately introduce water into the carbonation tank as the need is dictated by changes in the pressure head. Such changes are an indication of either dispensing of soda, or the absorption of the CO₂ gas into the soda within the tank, both conditions indicating a need for replenishment of water into the soda tank. The addition of water to the carbonation tank may proceed as a function of pressure within the tank, as a function of the time period of a dispensing cycle, or as a combination of time and pressure.

Description

Technical Field

The invention herein resides in the art of beverage dispensers and, more particularly, to a carbonation system to be employed therewith. More specifically, the invention relates to a carbonation system absent floats or soda level sensors, and in which control of replenishment of water in the carbonation tank is achieved solely by monitoring the pressure head within the tank.

Background Art

It is well known that soft drink dispensers require the implementation of soda generators or carbonation systems to generate carbonated water from sources of plain water and carbon dioxide (CO₂) gas. Previously known carbonation systems are of two types, the so-called motorless carbonators as taught by U.S. Patent 4,882,097, and the motored carbonators in which a motor driven pump is employed to replenish water to the soda tank as the soda is dispensed.
In the motorless carbonators, CO₂ gas is exhausted during the refill cycle. While such exhausting is not objectionable in most operations, concerns of costs of exhausted CO₂ gas become more extensive in high volume operations where the amount of exhausted gas becomes significant.
In motored carbonators, liquid level controls have typically been employed to signal the need for adding water to the tank. Typically, liquid level control units such as floats or sensor probes have been employed for this purpose. Such prior art tanks typically have a significantly large pressure head space to minimize head compression and resulting restrictions on refill cycles. For example, two gallon tanks often have one gallon of head space when the tank is "full," allowing for only one gallon of soda. The tank then enters a refill cycle when the soda level has dropped to about a half of a gallon, providing a gallon and a half of head space. Such necessary head space is not only wasteful, but provides for a high pressure head on the refill cycle which does not lower until some dispensing from the recharge tank has been undertaken. Accordingly, the flow from the soda tank is not constant, but takes place under an elevated pressure head on the initial dispensing cycles after refill. Further, such prior art carbonation tanks often found the user with but a half gallon of soda at the commencement of a heavy use period.
Liquid level controls such as sensor probes and floats create maintenance problems because of the operating environment in which they are found. Sediment build up on such devices is not at all uncommon and, to varying degrees, the same have been found to be somewhat unreliable in use. While the sensor probes are found to be far more reliable than floats, they still result in a system which is liquid level dependent, and not refilled or replenished on a basis of fluctuations in the pressure head.

Disclosure of Invention

In light of the foregoing, it is a first aspect of the invention to provide a carbonation system which does not employ float switches for replenishing the carbonation tank.
Another aspect of the invention is to provide a carbonation system which does not rely upon probe switches within the carbonation tank to control the refilling or recycling thereof.
Yet another aspect of the invention is the provision of a carbonation system in which the CO₂ pressure head within the carbonation tank remains substantially constant over time, and in which recycling or refilling of the carbonation tank is achieved as a function of changes sensed in the pressure head, not in liquid levels.
Still a further aspect of the invention is to provide a carbonation system in which a motor driving water to the carbonation tank is actuated only when the soda within the tank is unsaturated or when a dispensing cycle is engaged.
Yet an additional aspect of the invention is the provision of a carbonation system in which the refilling and recharging of the carbonation tank occurs as a function of changes in head pressure within the tank, and not as a function of liquid levels.
Still an additional aspect of the invention is the provision of a carbonation system which is substantially unaffected by temperature changes, assuring full saturation of CO₂ gas within the carbonated water, independent of ambient conditions.
Yet an additional aspect of the invention is the provision of a carbonation tank which is reliable and durable in operation, inexpensive to construct and maintain, and conducive to implementation with state of the art elements.
The foregoing and other aspects of the invention which will become apparent as the detailed description proceeds are achieved by a carbonator for generating soda, comprising: a tank having a supply of soda beneath a pressure head of CO₂ gas; a source of water communicating with said tank; a source of carbon dioxide gas communicating with said tank; and switch means interposed between said tank and said source of water for introducing water from said source of water into said tank when said pressure head drops below a particular level.
Other aspects of the invention are attained by a carbonator, comprising: a tank maintaining a reservoir of soda beneath a pressure head of CO₂ gas; pump means for pumping water into said tank; a source of carbon dioxide gas in communication with said tank; and a pressure switch interposed between said pump means and said pressure head, said pressure switch activating said pump means when said pressure head drops below a first level, and deactivating said pump means when said pressure head exceeds a second level.
Still further aspects of the invention are attained by a soda generator, comprising: a tank having a supply of soda beneath a pressure head of CO₂ gas; a source of water communicating with said tank; a source of CO₂ gas communicating with said tank; a dispensing valve communicating with said tank for dispensing soda therefrom; and control means interposed between said dispensing valve and said source of water for actuating said dispensing valve to dispense soda from said tank and to pass water from said source of water to said tank.

Description of Drawing

For a complete understanding of the objects, techniques and structure of the invention reference should be made to the following detailed description and accompanying drawing wherein a schematic diagram of the carbonation system of the invention is shown.

Best Mode For Carrying Out The Invention

Referring now to the drawing, it can be seen that a carbonation system according to the invention is designated generally by the numeral 10. The system 10 employs a carbonation tank or soda tank 12, which may be of any suitable construction, but is preferably a sealed vessel of stainless steel construction. The tank 12 maintains a reservoir of carbonated water or soda 14 beneath a pressure head 16 of carbon dioxide (CO₂) gas. As is well known to those skilled in the art, the soda is generated by entraining CO₂ gas in water, or otherwise saturating the water with the gas.
An output conduit 18 communicates with the reservoir of soda 14 at one end thereof, and terminates at a dispensing head 20 of a soft drink dispenser at the other. As will be appreciated by those skilled in the art, a dispensing valve 21, such as a solenoid valve or the like, is positioned within the conduit 18 to initiate and terminate the flow of soda from the reservoir 14 out of the dispensing head 20. Of course, it will be appreciated that the flow of soda is achieved by the force imparted by the pressure head 16 thereupon.
A water source 22, such as a municipal water supply or the like, communicates through an input conduit 24 to a high pressure water pump 26 of suitable nature. It will be readily appreciated by those skilled in the art that a high pressure water pump suitable for the intended purposes of the invention can be either a diaphragm, vane, bag-in-box, positive displacement, or other type of pump capable of forcing water through an output conduit 28. The output conduit 28 communicates with a spray nozzle 30 maintained within the tank 12 at the top thereof.
Also provided as part of the system 10 is a pressure regulated source of CO₂ gas 32. While the source of CO₂ gas 32 may be maintained at any of various pressures, for purposes of the preferred embodiment presented herein, it is presented that the source 32 provides CO₂ gas under a pressure head of 90 psi. The CO₂ gas passes from the source 32 through a conduit 34 and thence through a spray nozzle 36 also maintained within the tank 12 at the top thereof as shown.
A conduit 38 communicates with the conduit 34 to communicate the pressure of the pressure head 16 to a pressure switch 40. As shown, the pressure switch 40 is interconnected between an electrical voltage power source 42 and the pump 26. In a preferred embodiment of the invention, with the pressure regulated source of CO₂ gas 32 having a characteristic pressure of 90 psi, the pressure switch 40 will be set to switch "on" at 95 psi, and to switch "off" at 125 psi. In other words, when the pressure from the pressure head 16 is communicated through the conduits 34, 38 to the pressure switch 40, and when such pressure is less than 95 psi, the pump 26 will be turned on to pump water from the water source or municipal supply 22 through the conduit 28 and nozzle 30 and into the tank 12. Such pumping action will continue until the pressure head 16 reaches the level of 125 psi, at which time the switch 40 will turn the motor 26 off.
It will be appreciated by those skilled in the art that a check valve 44 is associated with the pressure regulated source of CO₂ gas 32 before the junction of the conduits 38, 34. The check valve 44 prevents any back flow to the source 32 when the pressure head 16 is greater than the pressure regulated source 32.
The operation of the instant invention will be discussed below, premised upon the provision that the source 32 provides CO₂ gas at 90 psi and the pressure switch 40 is operative to actuate upon sensing 95 psi in the conduit 38, and deactivated upon sensing a pressure in such conduit of 125 psi or greater. To begin operation, it will be assumed that the pressure head 16 is at 125 psi. When a dispensing cycle is engaged, the solenoid valve 21 is opened such that the pressure head 16 urges soda from the reservoir 14 through the conduit 18 and out of the dispensing head 20. Immediately upon opening of the valve 21, the pressure head 16 sharply drops and, upon reaching the level of 95 psi, the switch 40 actuates the pump 26, passing water through the conduit 28 and nozzle 30 into the tank 12. At the same time, CO₂ gas is emitted from the nozzle 36 and absorbed by the water injected via the nozzle 30 and by the soda within the reservoir 14. The CO₂ gas also serves to replenish the head 16.
At the end of the dispensing cycle, the dispensing valve 21 closes. Water continues to be driven by the pump 26 through the nozzle 30, and CO₂ gas continues to be emitted through the nozzle 36, until the rising level of liquid within the tank 12 causes the head 16 to reach 125 psi, as sensed by the pressure switch 40. At that time, the switch 40 deactivates the motor 26 and the tank 12 takes a quiescent saturated state with a reservoir of soda 14 having a pressure head 16 of CO₂ gas maintained thereabove on the order of 125 psi. Upon actuation of the dispensing valve 21, the cycle begins anew.
In the preferred embodiment of the invention, the pump 26, pressure source 32, output conduit 18, and dispensing head 20 are relatively sized and configured such that the rate of flow of soda from the tank 12 and out of the dispensing head 20 is greater than the rate of flow of water into the tank 12 from the pump 26. Accordingly, the pump 26 runs only once during a dispensing cycle. While the concept of the invention may readily extend to systems in which the flow rate of water into the tank 12 exceeds the flow rate of soda therefrom, such an arrangement may result in excessive cycling of the motor 26.
It will be appreciated that the system 10 operates upon the premise of monitoring the pressure head 16 and accordingly refilling the tank 12 with water. It will be appreciated by those skilled in the art that the pressure head 16 is affected by either dispensing of soda by means of actuating the dispensing valve 21, or by the absorption of CO₂ gas into the soda 14. Since the most important aspect of attaining and maintaining proper carbonation is to assure that a proper pressure head is maintained upon the soda, the instant invention operates independent of liquid level, operating solely upon the sensing of changes in the pressure head 16. In the specific embodiment shown, the pressure head 16 is assured of being maintained at a level of at least 95 psi, for when the head 16 drops below that level, the pressure switch 40 activates the pump 26 to introduce additional water into the tank 12, decreasing the volume of the head 16, thereby increasing the magnitude of the pressure head.
It will be readily appreciated by those skilled in the art that the structure and technique of the instant invention assures full saturation of the soda within the reservoir 14 irrespective of the temperature or other ambient conditions. Further, by maintaining the "on" pressure level of the pressure switch 40 above the pressure level of the regulated pressure source 32, complete saturation of the soda within the reservoir 14 is assured.
It is further contemplated that cycling of the carbonation system 10 may be time controlled, or controlled by combined functions of time and pressure. In this regard, a microprocessor or suitable control unit 46 may be interposed between the dispensing valve 21, pump 26, and pressure switch 40. Such interconnection gives rise to a number of operational modes.
With the flow rate of soda from the tank 12 and the flow rate of water into the tank 12 both being known, and with the flow rate of water into the tank being less than that of soda from the tank, the duration of actuation of the pump 26 can readily be determined and controlled by the control unit 46 as a function of the duration of actuation of the valve 21 for the dispensing cycle. The period of actuation of the pump 26 is so related to the period of actuation of the valve 21 to assure that the volume of water into the tank 12 is equal to the volume of soda dispensed therefrom during the dispensing cycle. In such a system, actuation of the pump 26 will typically be subsequent to actuation of the valve 21.
The system 10 may operate on a combination of time and pressure controls. The pump 26 may be actuated by the control unit 46 upon actuation of the valve 21, or a short time thereafter. Upon closure of the valve 21 at the end of the dispensing cycle, the pump 26 may continue to introduce water into the tank 12 until the pressure head 16 reaches the high threshold of 125 psi as discussed above. At such time, the pressure switch 40, either directly or through the control unit 46, terminates operation of the pump 26.
Thus it can be seen that the objects of the invention have been satisfied by the structure presented above. While in accordance with the patent statutes only the best mode and preferred embodiment of the invention has been presented and described in detail, it is to be understood that the invention is not limited thereto or thereby. Accordingly, for an appreciation of the true scope and breadth of the invention reference should be made to the following claims.

Claims

A carbonator for generatings soda, comprising:
a tank having a supply of soda beneath a pressure head of CO₂ gas;
a source of water communicating with said tank;
a source of carbon dioxide gas communicating with said tank; and
switch means interposed between said tank and said source of water for introducing water from said source of water into said tank when said pressure head drops below a particular level.
The carbonator according to claim 1, wherein said switch means comprises a pressure switch.
The carbonator according to claim 2, wherein said source of water comprises a water pump selectively actuated and deactivated by said pressure switch.
The carbonator according to claim 3, wherein said pressure switch actuates said water pump when said pressure head is below a first value, and deactivates said water pump when said pressure head exceeds a second value.
The carbonator according to claim 4, wherein said source of carbon dioxide gas is a regulated pressure source.
The carbonator according to claim 5, wherein said regulated pressure source of carbon dioxide gas is at a pressure lower than said first value.
The carbonator according to claim 6, further comprising an output conduit having a first end thereof received within said tank and having a dispensing valve at a second end thereof, said soda being dispensed through said output conduit under force of said pressure head upon opening of said dispensing value.
A carbonator, comprising:
a tank maintaining a reservoir of soda beneath a pressure head of CO₂ gas;
pump means for pumping water into said tank;
a source of carbon dioxide gas in communication with said tank; and
a pressure switch interposed between said pump means and said pressure head, said pressure switch activating said pump means when said pressure head drops below a first level, and deactivating said pump means when said pressure head exceeds a second level.
The carbonator according to claim 8, wherein said source of carbon dioxide gas is pressure regulated at a pressure level below said first level.
The carbonator according to claim 9, wherein an output conduit having a dispensing valve therein communicates with said reservoir of soda, said soda being dispensed from said reservoir under force of said pressure head of CO₂ gas.
The carbonator according to claim 9, wherein said soda and said pressure head of CO₂ gas are monitored solely by said pressure switch.
A soda generator, comprising:
a tank having a supply of soda beneath a pressure head of CO₂ gas;
a source of water communicating with said tank;
a source of CO₂ gas communicating with said tank;
a dispensing valve communicating with said tank for dispensing soda therefrom; and
control means interposed between said dispensing valve and said source of water for actuating said dispensing valve to dispense soda from said tank and to pass water from said source of water to said tank.
The soda generator according to claim 12, wherein said control means activates said dispensing valve for a period of time sufficient to dispense a desired quantity of soda, said control means comprising a pump actuated for a period of time sufficient to introduce an equal quantity of water into said tank.
The soda generator according to claim 13, wherein said soda is dispensed at a first flow rate, and said water is introduced into said tank at a second flow rate, said second flow rate being less than said first flow rate.
The soda generator according to claim 14, wherein said control means actuates said pump following actuation of said dispensing valve to commence dispensing of soda.
The soda generator according to claim 12, wherein said control means comprises a pressure sensor in communication with said pressure head, said control means introducing water into said tank from said source of water following actuation of said dispensing valve until said pressure head reaches a predetermined level.
The soda generator according to claim 16, wherein said control means comprises a pump communicating with said source of water, said pump being actuated following actuation of said dispensing valve, and continuing after closure of said dispensing valve until said pressure head reaches said predetermined level.