Method and apparatus for determining pump wear

• US 5,563,351 A
• Filed: 03/31/1994
• Issued: 10/08/1996
• Est. Priority Date: 03/31/1994
• Status: Expired due to Term

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Miller, Dean E.
• Primary Examiner(s): Chilcot, Richard
• Assistant Examiner(s): Dougherty, Elizabeth L.
• Application Number:
  US08/221,143
• Time in Patent Office: 922 Days
• Field of Search: 73/7, 73/168, 73/195, 73/861.42, 73/861.59, 73/861.63, 364/510
• US Class Current: 73/861.42
• CPC Class Codes: F04B 2205/10 Inlet temperature
• CPC Class Codes: F04B 2207/041 of flow
• CPC Class Codes: F04B 2207/042 of pressure
• CPC Class Codes: F04B 49/10 Other safety measures
• CPC Class Codes: G01F 1/44 Venturi tubes
• CPC Class Codes: G01P 5/14 by measuring differences of pressure in the fluid

Abstract

An apparatus is provided for detecting wear in a pump. The apparatus includes a case drain connected to the pump case, a flow sensor for producing signals indicative of case drain flow, a processor for determining whether pump wear has exceeded a predetermined level and for indicating a fault in response to the pump wear exceeding the predetermined level.

Claims

1. An apparatus for detecting wear in a pump having a case, comprising:

a case drain connected to the pump case;

a flow sensor connected to said case drain, said flow sensor producing pressure signals indicative of case drain flow;

means for calculating a flow rate in response to said pressure signals;

means for calculating a rate of change of said flow rate;

memory means for storing said flow rate and said rate of change of said flow rate;

means for comparing said rate of change of said of said flow rate to a predetermined constant; and

means for indicating a fault in response to said rate of change of said flow rate exceeding said predetermined constant.

3. An apparatus, as set forth in claim 1 wherein said flow sensor includes a venturi.

2. An apparatus for detecting wear in a pump having a case, comprising:

a case drain connected to the pump case;

a flow sensor connected to said case drain, said flow sensor producing pressure signals indicative of case drain flow;

means for calculating a flow rate in response to said pressure signals;

means for calculating a rate of change of said flow rate;

means for comparing said rate of change to a second predetermined constant; and

means for indicating a fault in response to said rate of change exceeding said second predetermined constant.

4. A method for determining the wear of a pump having a case drain, comprising the steps of:

measuring the flow of fluid in the case drain;

calculating a rate of change of said flow rate;

comparing the rate of change of said flow rate to a predetermined constant; and

indicating a fault in response to the rate of change of said flow exceeding the predetermined constant.

5. A method, a set forth in claim 4, wherein said step of comparing the rate of change of said flow rate to a predetermined constant is performed in response to the pump being in a predefined operating state.

6. A method for determining the wear of a pump having a case drain, comprising the steps of:

measuring the flow of fluid in the case drain;

comparing the flow rate to a predetermined constant;

indicating a fault in response to the flow exceeding the predetermined constant;

calculating a rate of change of said flow rate;

comparing said rate of change to a second predetermined constant; and

indicating a fault in response to said rate of change exceeding said second predetermined constant.