REFRIGERATION SYSTEM INCLUDING A FLEXIBLE SENSOR

• US 20090056353A1
• Filed: 08/30/2007
• Published: 03/05/2009
• Est. Priority Date: 08/30/2007
• Status: Abandoned Application

• Current Assignee: Hussmann Corporation (Panasonic Holdings Corporation)
• Original Assignee: Hussmann Corporation (Panasonic Holdings Corporation)
• Inventors: Sunderland, Ted W.
• Application Number:
  US11/847,534
• Publication Number:
  US 20090056353A1
• Time in Patent Office: Days
• US Class Current: 62/214
• CPC Class Codes: F25B 2700/04 Refrigerant level
• CPC Class Codes: F25B 2700/13 Mass flow of refrigerants
• CPC Class Codes: F25B 2700/135 through the evaporator
• CPC Class Codes: F25D 17/06 by forced circulation
• CPC Class Codes: F25D 23/003 for cooling refrigerating machinery
• CPC Class Codes: F25D 2323/0023 Control of the air flow cooling refrigerating machinery
• CPC Class Codes: F25D 25/02 by shelves
• CPC Class Codes: F25D 2700/02 Sensors detecting door opening
• CPC Class Codes: F25D 29/008 Alarm devices
• CPC Class Codes: F25D 7/00 Devices using evaporation effects without recovery of the vapour butter or cheese dishes with cooling devices A47G19/26
• CPC Class Codes: G01F 1/28 by drag-force, e.g. vane type or impact flowmeter
• CPC Class Codes: G01F 23/24 by measuring variations of resistance of resistors due to contact with conductor fluid
• CPC Class Codes: G01F 23/241 for discrete levels
• CPC Class Codes: G01F 23/36 using electrically actuated indicating means G01F23/38 takes precedence

Abstract

A refrigeration system including a compressor configured to compress a refrigerant, a condenser in fluid communication with the compressor and configured to remove heat from the refrigerant, and an expansion valve in fluid communication with the condenser and configured to decrease a pressure of the refrigerant. The refrigeration system also includes an evaporator in fluid communication with the expansion valve and configured to facilitate heat exchange between the refrigerant and another fluid, and a sensor configured to bend to measure a property of the refrigeration system. The sensor including a flexible substrate and a conductive material applied to the flexible substrate and having a resistance that changes in response to bending of the flexible substrate to generate a signal indicative of the property.

Claims

1. A refrigeration system comprising:

a compressor configured to compress a refrigerant;

a condenser in fluid communication with the compressor and configured to remove heat from the refrigerant;

an expansion valve in fluid communication with the condenser and configured to decrease a pressure of the refrigerant;

an evaporator in fluid communication with the expansion valve and configured to facilitate heat exchange between the refrigerant and another fluid; and

a sensor configured to bend to measure a property of the refrigeration system, the sensor including

a flexible substrate, and

a conductive material applied to the flexible substrate and having a resistance that changes in response to bending of the flexible substrate to generate a signal indicative of the property.

2. The refrigeration system of claim 1, wherein the sensor includes a sleeve positioned around at least a portion of the flexible substrate.

3. The refrigeration system of claim 1, wherein the property is a liquid flow within at least one component of the refrigeration system.

4. The refrigeration system of claim 3, wherein the liquid flow is a refrigerant flow.

5. The refrigeration system of claim 3, wherein the liquid flow is an oil flow.

6. The refrigeration system of claim 3, wherein failure of the expansion valve is determined by measuring the liquid flow with the sensor.

7. The refrigeration system of claim 3, wherein a position of the expansion valve is determined by measuring the liquid flow with the sensor.

8. The refrigeration system of claim 3, wherein a run time of the compressor is determined by measuring the liquid flow with the sensor.

9. The refrigeration system of claim 1, wherein the property is an air flow.

10. The refrigeration system of claim 9, wherein a demand defrost is triggered by measuring the air flow with the sensor.

11. The refrigeration system of claim 9, wherein at least one of the condenser and the evaporator includes a fan, and wherein failure of the fan is determined by measuring the air flow with the sensor.

12. The refrigeration system of claim 9, further comprising a display case including an air return grille, wherein blockage of the air return grille is determined by measuring the air flow with the sensor.

13. The refrigeration system of claim 9, wherein blockage of the condenser is determined by measuring the air flow with the sensor.

14. The refrigeration system of claim 1, wherein the property is a fluid level within at least one component of the refrigeration system.

15. The refrigeration system of claim 14, further comprising a receiver configured to hold a portion of the refrigerant, wherein the fluid level is a refrigerant level within the receiver.

16. The refrigeration system of claim 14, wherein the fluid level is an oil level within the compressor.

17. The refrigeration system of claim 14, further comprising a display case including a drain, wherein blockage of the drain is determined by measuring the fluid level within the display case with the sensor.

18. The refrigeration system of claim 1, further comprising a display case including a door, wherein the property is a position of the door.

19. The refrigeration system of claim 1, further comprising a display case including a shelf, wherein the property is a load condition of the shelf.

20. The refrigeration system of claim 1, further comprising a circuit breaker, wherein the property is a status of the circuit breaker.

21. The refrigeration system of claim 1, further comprising a contactor configured to transmit power to at least one component of the refrigeration system, wherein the property is a status of the contactor.

22. The refrigeration system of claim 1, further comprising a second refrigeration unit configured to circulate a second refrigerant that exchanges heat with the first-mentioned refrigerant, wherein the property is a fluid flow within the second refrigeration unit.

23. A method of measuring a property of a refrigeration system, the refrigeration system including a compressor, a condenser in fluid communication with the compressor, an expansion valve in fluid communication with the condenser, and an evaporator in fluid communication with the expansion valve, the method comprising:

providing a sensor including a flexible substrate and a conductive material applied to the flexible substrate, the conductive material having a resistance that changes in response to bending of the flexible substrate;

compressing a refrigerant with the compressor;

removing heat from the refrigerant with the condenser;

decreasing a pressure of the refrigerant with the expansion valve;

exchanging heat between the refrigerant and another fluid with the evaporator; and

bending the sensor to generate a signal indicative of a property of the refrigeration system.

24. The method of claim 23, wherein bending the sensor includes bending the sensor to measure a liquid flow within at least one component of the refrigeration system.

25. The method of claim 24, wherein the liquid flow is a refrigerant flow.

26. The method of claim 24, wherein the liquid flow is an oil flow.

27. The method of claim 24, wherein bending the sensor to measure a liquid flow includes bending the sensor to determine a failure of the expansion valve.

28. The method of claim 24, wherein bending the sensor to measure a liquid flow includes bending the sensor to determine a position of the expansion valve.

29. The method of claim 24, wherein bending the sensor to measure a liquid flow includes bending the sensor to determine a run time of the compressor.

30. The method of claim 23, wherein bending the sensor includes bending the sensor to measure an air flow within at least one component of the refrigeration system.

31. The method of claim 30, wherein bending the sensor to measure an air flow includes bending the sensor to trigger a demand defrost.

32. The method of claim 30, wherein at least one of the condenser and the evaporator includes a fan, and wherein bending the sensor to measure an air flow includes bending the sensor to determine a fan failure.

33. The method of claim 30, wherein the refrigeration system further includes a display case having an air return grille, and wherein bending the sensor to measure an air flow includes bending the sensor to determine blockage of the air return grille.

34. The method of claim 30, wherein bending the sensor to measure an air flow includes bending the sensor to determine blockage of the condenser.

35. The method of claim 23, wherein bending the sensor includes bending the sensor to measure a fluid level within at least one component of the refrigeration system.

36. The method of claim 35, wherein the refrigerant system further includes a receiver configured to hold a portion of the refrigerant, and wherein bending the sensor to measure a fluid level includes bending the sensor to measure a refrigerant level within the receiver.

37. The method of claim 35, wherein bending the sensor to measure a fluid level includes bending the sensor to measure an oil level within the compressor.

38. The method of claim 35, wherein the refrigeration system further includes a display case having a drain, and wherein bending the sensor to measure a fluid level includes bending the sensor to determine blockage of the drain.

39. The method of claim 23, wherein the refrigeration system further includes a display case having a door, and wherein bending the sensor includes bending the sensor to determine a position of the door.

40. The method of claim 23, wherein the refrigeration system further includes a display case having a shelf, and wherein bending the sensor includes bending the sensor to determine a load condition of the shelf.

41. The method of claim 23, wherein the refrigeration system further includes a circuit breaker, and wherein bending the sensor includes bending the sensor to determine a status of the circuit breaker.

42. The method of claim 23, wherein the refrigeration system further includes a contactor configured to transmit power to at least one component of the refrigeration system, and wherein bending the sensor includes bending the sensor to determine a status of the contactor.

43. The method of claim 23, wherein the refrigeration system further includes a second refrigeration unit configured to circulate a second refrigerant that exchanges heat with the first-mentioned refrigerant, and wherein bending the sensor includes bending the sensor to measure a fluid flow within the second refrigeration unit.

44. An evaporative cooler comprising:

a housing having at least one vent and configured to contain water;

a blower positioned within the housing and configured to draw air through the at least one vent;

an evaporator pad positioned adjacent to the at least one vent;

a pump configured to spray at least a portion of the evaporator pad with the water; and

a sensor configured to bend to measure a property of the evaporative cooler, the sensor including

a flexible substrate, and

a conductive material applied to the flexible substrate and having a resistance that changes in response to bending of the flexible substrate to generate a signal indicative of the property.

45. The evaporative cooler of claim 44, wherein the property is a water level within the housing.

46. The evaporative cooler of claim 44, wherein the property is a spray flow from the pump.