Apparatus for protecting pumps against cavitation

• US 6,145,332 A
• Filed: 06/16/1999
• Issued: 11/14/2000
• Est. Priority Date: 06/16/1999
• Status: Expired due to Fees

• Current Assignee: DTE Energy Technologies, Inc. (DTE Energy Company)
• Original Assignee: DTE Energy Technologies, Inc. (DTE Energy Company)
• Inventors: Hyde, Robert E.
• Primary Examiner(s): Doerrler, William
• Assistant Examiner(s): NORMAN, MARC E
• Application Number:
  US09/334,073
• Time in Patent Office: 517 Days
• Field of Search: 62/DIG. 2, 62/190, 62/498, 62/118, 340/619, 340/621, 340/623
• US Class Current: 62/190
• CPC Class Codes: F04B 2205/503 of gas in a liquid flow, e.g. gas bubbles
• CPC Class Codes: F04B 49/02 Stopping, starting, unloading or idling control
• CPC Class Codes: F04D 15/0209 responsive to a condition of the working fluid F04D15/029 takes precedence
• CPC Class Codes: F04D 29/669 especially adapted for liquid pumps F04D29/18 takes precedence
• CPC Class Codes: F25B 2500/01 Geometry problems, e.g. for reducing size
• CPC Class Codes: F25B 2700/04 Refrigerant level
• CPC Class Codes: F25B 41/00 Fluid-circulation arrangements
• CPC Class Codes: F25B 41/006 optical fluid control arrangements
• CPC Class Codes: G01F 23/2925 using electrical detecting means
• CPC Class Codes: G01F 23/2965 Measuring attenuation of transmitted waves
• CPC Class Codes: G01F 23/74 for sensing changes in level only at discrete points
• CPC Class Codes: Y10S 62/02 Refrigerant pumps

Abstract

Apparatus for protecting a liquid refrigerant pump from damage due to cavitation and loss of lubrication by inclusion of means for detecting the presence of vaporized refrigerant at the pump inlet and deactivating the pump in response thereto.

Claims

1. In a vapor-compression refrigeration apparatus utilizing a fluid refrigerant and comprising a compressor, a condenser, a liquid refrigerant pump, an expansion device, and an evaporator, the improvement comprising:

vapor detection means for detecting the presence of vapor at or near the inlet of said liquid refrigerant pump and for deactivating said pump in response to the detection of vapor.

2. The apparatus of claim 1, including liquid refrigerant detection means for detecting the presence of liquid refrigerant at or near said inlet and for activating said pump in response to the detection of liquid.

3. The apparatus of claim 1 wherein said vapor detection means comprises a sonic transducer.

4. The apparatus of claim 2 wherein said liquid refrigerant detection means comprises a sonic transducer.

5. The apparatus of claim 1 wherein said vapor detection means comprises a float transducer.

6. The apparatus of claim 2 wherein said liquid refrigerant detection means comprises a float transducer.

7. The apparatus of claim 1 wherein said vapor detection means comprises an optical transducer.

8. The apparatus of claim 2 wherein said liquid refrigerant detection means comprises an optical transducer.