Beverage dispenser and automatic shut-off valve

• US 6,684,920 B2
• Filed: 09/27/2002
• Issued: 02/03/2004
• Est. Priority Date: 09/28/2001
• Status: Expired due to Fees

• Current Assignee: Manitowoc Foodservice Companies Incorporated (The Manitowoc Company, Inc.)
• Original Assignee: Manitowoc Foodservice Companies Incorporated (The Manitowoc Company, Inc.)
• Inventors: Seitz, Forrest S., Myers, Denise K., Krebs, Philip M., Cochran, John D., Darby, Brian J.
• Primary Examiner(s): Huson, Gregory L.
• Assistant Examiner(s): DEVORE, PETER T
• Application Number:
  US10/259,541
• Publication Number:
  US 20030084957A1
• Time in Patent Office: 494 Days
• Field of Search: 141/95, 141/100, 141/105, 141/198, 141/206, 141/267, 141/283, 141/351, 141/360
• US Class Current: 141/198
• CPC Class Codes: B67D 1/0085 electro-mechanical
• CPC Class Codes: B67D 1/1238 comprising means for detecting the liquid level in vessels to be filled, e.g. using ultrasonic waves, optical reflexion, probes
• CPC Class Codes: B67D 1/124 the flow being started or stopped by means actuated by the vessel to be filled, e.g. by switches, weighing
• CPC Class Codes: B67D 2001/0089 operated by lever means
• CPC Class Codes: G07F 13/065 for drink preparation

Abstract

A beverage mixing and dispensing valve, or a beverage dispenser including the valve, includes an automatic shut-off features. A user presses a cup or container against a lever on a soft-drink dispenser. The lever closes a switch to activate the opening of a solenoid-operated valve. At the same time, a detection circuit is monitored to determine whether overflow of drink or foam has occurred. When drink or foam overflows and bridges a gap between two metal conductors on the lever, resistance is lowered and electricity flows in the detection circuit. The valve then automatically shuts off the flow of beverage. Energy is saved in keeping the valve open using a pulse width modulation (PWM) technique for voltage to the solenoid, rather than using a steady-state voltage.

Claims

1. An automatic shut-off valve for dispensing a beverage into a container, the automatic shut-off valve comprising:

a) at least one electrically-operated valve;

b) a detection circuit comprising at least two spaced conductors, the detection circuit wholly external to the container and capable of detecting conductivity between the at least two spaced conductors; and

c) a controller that shuts off the at least one electrically-operated valve automatically when liquid or foam from a beverage creates a conductive path between the at least two spaced conductors.

2. The automatic shut-off valve according to claim 1 wherein the electrically-operated valve is a solenoid valve.

3. The automatic shut-off valve according to claim 2 wherein the solenoid is operated using a pulse-width-modulation technique.

4. The automatic shut-off valve according to claim 3 further comprising at least one power switch electrically connected to the solenoid, wherein applying the pulse-width-modulation technique by means of the power switch holds the solenoid open or closed.

5. The automatic shut-off valve according to claim 4 wherein the power switch is selected from the group consisting of a transistor, a FET, a MOSFET, a thyristor, an IGBT, a silicon-controlled rectifier, an MOS-controlled thyristor, and a triac.

6. The automatic shut-off valve according to claim 1 wherein the at least two conductors comprise stainless steel.

7. The automatic shut-off valve according to claim 1 wherein the at least two conductors are spaced apart by thermoplastic material.

8. The automatic shut-off valve according to claim 7 wherein the thermoplastic material comprises a blend of polycarbonate and PET polyester.

9. The automatic shut-off valve according to claim 1 further comprising a a microswitch, wherein the two spaced conductors are located on the lever and the lever can activate the microswitch which in turn controls power to the controller.

10. The automatic shut-off valve according to claim 1 wherein the controller is a microprocessor controller.

11. The automatic shut-off valve according to claim 1 wherein the two spaced conductors are separated by a peaked surface.

12. An automatic shut-off valve for dispensing a beverage into a container, the automatic shut-off valve comprising:

a) a detection circuit comprising at least two spaced conductors, the detection circuit wholly external to the container; and

b) a controller controlling at least one power switching circuit, and connected to at least one electrically-operated solenoid valve,

wherein a user may dispense a beverage by activating the power switching circuit to open the at least one electrically-operated solenoid valve, and the controller automatically shuts the at least one electrically-operated solenoid valve upon detecting a change in the detection circuit.

13. The automatic shut-off valve according to claim 12 further comprising a lever connected to a microswitch for activating the switching circuit.

14. The automatic shut-off valve according to claim 13 wherein the two spaced conductors are on a surface of the lever.

15. The automatic shut-off valve according to claim 12 wherein the at least two spaced conductors are mounted on an insulative portion, the conductors forming sensors for the detection circuit, and wherein controller automatically shuts off the at least one electrically-operated solenoid valve when the at least two conductors of the lever are in contact with beverage foam or liquid.

16. The automatic shut-off valve according to claim 12 wherein the power switching circuit is a pulse-width-modulation circuit.

17. The automatic shut-off valve according to claim 12 wherein the power switching circuit comprises at least one power switch.

18. The automatic shut-off valve according to claim 17 wherein the at least one power switch is selected from the group consisting of a transistor, a FET, a MOSFET, a thyristor, an IGBT, a silicon-controlled rectifier, an MOS-controlled thyristor, and a triac.

19. The automatic shut-off valve according to claim 12 wherein the at least two conductors are mounted on a lever, the lever having a peaked surface allowing beverage foam or liquid to condense and to dissipate.

20. The automatic valve according to claim 12 wherein the at least two conductors are stainless steel conductors spaced apart by thermoplastic material.

21. The automatic shut-off valve according to claim 20 wherein the thermoplastic material comprises a blend of polycarbonate and PET polyester.

22. A method of dispensing a beverage with an automatic shut-off valve, the method comprising:

a) providing a container having an open mouth;

b) opening at least one electrically-operated valve to begin dispensing the beverage into the container;

c) detecting a change in an electrical detection circuit wholly external to the container while dispensing the beverage; and

d) automatically closing the electrically-operated valve upon detecting a change in the electrical detection circuit.

23. The method of claim 22 further comprising keeping the electrically-operated valve open by a pulse-width-modulation technique while dispensing the beverage.

24. The method of claim 22 wherein opening the at least one valve is accomplished by pressing a lever, touching a screen, or pushing a button.

25. The method of claim 22 wherein detecting the change in the detection circuit and automatically closing the valve is accomplished via a controller.

26. The method of claim 22 wherein the detection circuit detects conductivity between spaced conductors to close the electrically-operated valve.

27. The method of claim 26 further comprising

e) waiting a period of time after automatically closing the electrically-operated valve and automatically checking whether the detection circuit is in a non-conducting state, and if so, initiating a top-off routine.

28. The method of claim 27 wherein the top-off routine comprises:

i) opening the at least one electrically-operated valve to begin dispensing the beverage into the container;

ii) detecting a subsequent change in the electrical detection circuit; and

iii) automatically closing the at least one electrically-operated valve upon detecting said subsequent change in the electrical detection circuit.

29. The method of claim 22 wherein the change in the detection circuit is caused by beverage liquid or foam contacting, or dissipating from, at least two conductors molded into a lever.

30. A method of dispensing a beverage into a container, the method comprising:

a) providing a container;

b) opening at least one solenoid valve to fill the container with the beverage;

c) keeping the valve open by a pulse-width-modulation technique while operating a detection circuit wholly external to the container; and

d) closing the valve automatically upon detecting a change in the detection circuit.

31. The method of claim 30 wherein the change in the detection circuit is a change in conductivity.

32. The method of claim 31 further comprising:

e) automatically rechecking the detection circuit to see if the detection circuit has gone to a non-conducting state and if so, initiating a top-off routine, wherein the top-off routine comprises

i) re-opening the at least one solenoid valve to top-off the container; and

ii) reclosing the valve automatically upon detecting a subsequent change in the detection circuit.

33. The method of claim 31 wherein the change in the detection circuit is caused by beverage foam or liquid contacting and thus forming a conductive path between sensors in the detection circuit, and thereafter dissipating so as to break the conductive path.

34. A method of dispensing a beverage, the method comprising:

a) providing a beverage dispenser having at least one solenoid-operated valve;

b) opening the at least one solenoid-operated valve to begin dispensing a beverage;

c) using a pulse-width-modulation technique to hold the solenoid-operated valve open during a filling operation; and

d) closing the at least one solenoid-operated valve upon a change in conductivity in a detection circuit comprising at least two spaced conductors, the detection circuit wholly external to a container for receiving the beverage.

35. The method of claim 34 wherein the valve is closed automatically by a technique selected from the group consisting of electrical detection and timing, wherein the timing technique is a back-up to the electrical detection technique.

36. The method of claim 34 further comprising:

e) automatically rechecking the detection circuit to see if the detection circuit has gone to a non-conducting state and if so, initiating a top-off routine, the top-off routine including;

i) re-opening the at least one solenoid valve to top-off the container; and

ii) reclosing the valve automatically.

37. The method of claim 36 wherein the valve automatically closes upon receiving a signal from a technique selected from the group consisting of electrical detection, infrared detection, ultrasonic detection, volumetric detection, weight detection, and timing.

38. The method of claim 36 wherein the step of re-opening occurs automatically after the detection circuit has gone to a non-conducting state and after a wait period of at least 0.25 seconds.

39. The method of claim 34 wherein the valve is opened by a technique selected from the group consisting of pressing a button, touching a screen, and pushing on a lever.

40. The method of claim 34 wherein the beverage is a soft drink.

41. The method of claim 34 wherein the change in conductivity in the detection circuit is caused by beverage foam or liquid contacting, or dissipating from, at least two conductors molded in a lever.

42. A beverage dispenser for dispensing a beverage into a container, the beverage dispenser comprising:

a) at least one mixing and dispensing valve for dispensing a beverage, the at least one mixing and dispensing valve comprising;

i) at least one solenoid-operated valve for controlling a flow of at least one fluid;

ii) a detection circuit comprising at least two spaced conductors, the detection circuit wholly external to the container and capable of detecting conductivity between the at least two spaced conductors; and

iii) a controller that shuts off the at least one solenoid-operated valve automatically when beverage foam or liquid creates a conductive path between the at least two spaced conductors;

b) a drip tray below the at least one mixing and dispensing valve; and

c) a housing for mounting the drip tray and the at least one mixing and dispensing valve.

43. The beverage dispenser of claim 42 wherein the at least two spaced conductors comprise stainless steel.

44. The beverage dispenser of claim 42 wherein the controller is in communication with the detection circuit, and the controller is programmed to open the at least one solenoid valve to fill a container with the beverage, and programmed to shut off the solenoid valve automatically when the conductive path is created.

45. The beverage dispenser of claim 42 wherein the controller is a microprocessor controller.

46. The beverage dispenser of claim 42 wherein the controller opens the at least one solenoid-operated valve based on an input received from the group consisting of a push-button, a touch-screen, and a lever.

47. The beverage dispenser of claim 46 further comprising a microswitch electrically connected to the controller and wherein the lever comprises the two spaced conductors and an insulative material having a crowned surface.

48. The beverage dispenser of claim 42 wherein the detection circuit is selected from the group consisting of an electrical detection circuit and a timer, wherein the timer is a back-up to the electrical detection circuit.

49. The beverage dispenser of claim 42 further comprising at least one power switch electrically connected to the at least one solenoid valve, wherein the controller keeps the at least one solenoid-operated valve open by a pulse-width-modulation technique while dispensing the beverage.

50. The beverage dispenser of claim 48 wherein the power switch is selected from the group consisting of a transistor, a FET, a MOSFET, a thyristor, an IGBT, a silicon-controlled rectifier, an MOS-controlled thyristor, and a triac.

51. The beverage dispenser of claim 42 further comprising a microswitch electrically connected to the controller.

52. The beverage dispenser of claim 42 wherein the at least two spaced conductors are separated by an insulative material having a peaked surface.

53. The beverage dispenser of clam 42 further comprising two fluid paths controlled by the at least one solenoid valve, a mixing chamber downstream from the two fluid paths, and a nozzle downstream of the mixing chamber.