Method and apparatus for determining an oil grade of an actuating fluid

• US 6,508,107 B2
• Filed: 01/14/2002
• Issued: 01/21/2003
• Est. Priority Date: 12/17/1999
• Status: Expired due to Fees

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Carrell, Darwin R., Speckhart, Gregory J., Lukich, Michael S., Kendrick, Larry E.
• Primary Examiner(s): Mancene, Gene
• Assistant Examiner(s): Castro, Arnold
• Application Number:
  US10/047,038
• Publication Number:
  US 20020083758A1
• Time in Patent Office: 372 Days
• Field of Search: 73/540.1, 73/540.2, 73/540.4, 73/540.9, 73/541.1, 73/541.4, 73/544.2, 123/381, 123/446
• US Class Current: 73/54.02
• CPC Class Codes: F02B 3/06 with compression ignition compression ignition engines using air or gas for blowing fuel into compressed air in cylinder F02B13/02
• CPC Class Codes: F02D 2200/0602 Fuel pressure
• CPC Class Codes: F02D 41/3809 Common rail control systems common rail apparatus F02M55/025, F02M63/0225
• CPC Class Codes: F02M 57/025 hydraulic, e.g. with pressure amplification
• CPC Class Codes: F02M 59/105 hydraulic drive F02M59/32 takes precedence

Abstract

The present invention provides a method and apparatus for determining the oil grade of an actuating fluid in a fuel system. The method includes the steps of determining an actuating fluid temperature, a pump speed, and a peak pressure or a timing event of the actuating fluid, and responsively determining the oil grade of the actuating fluid.

Claims

1. A method for determining an oil grade of an actuating fluid located within a fuel system, and the fuel system including a variable displacement pump, comprising the steps of:

determining a temperature of the actuating fluid;

determining a pump speed;

determining a maximum peak pressure of the actuating fluid; and

,

determining an oil grade of the actuating fluid in response to the temperature of the actuating fluid, the pump speed, and the maximum peak pressure.

2. A method, as set forth in claim 1, wherein the step of determining the oil grade further comprises the steps of:

comparing the temperature of the actuating fluid, the pump speed, and the maximum peak pressure with at least one of a plurality of pressure maps; and

,

determining the oil grade in response to the comparison.

3. A method, as set forth in claim 1, including the step of determining the maximum peak pressure in response to the pump moving from a maximum displacement position to a minimum displacement position.

4. A method, as set forth in claim 1, wherein the step of determining the maximum peak pressure further comprising the step of cranking the engine while determining the maximum peak pressure.

5. A method for determining an oil grade of an actuating fluid located within a fuel system, and the fuel system having a leakage orifice, comprising the steps of:

determining a temperature of the actuating fluid;

determining a pump speed;

determining a maximum peak pressure of the actuating fluid;

determining an oil grade of the actuating fluid in response to the temperature of the actuating fluid, the pump speed, and the maximum peak pressure.

6. A method, as set forth in claim 5, wherein the step of determining the oil grade further comprises the steps of:

comparing the temperature of the actuating fluid, the pump speed, and the maximum peak pressure with at least one of a plurality of pressure maps; and

,

determining said oil grade in response to the comparison.