Method for dynamically timing an apparatus

• US 4,158,305 A
• Filed: 03/31/1978
• Issued: 06/19/1979
• Est. Priority Date: 03/31/1978
• Status: Expired due to Term

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Tractor Co (Caterpillar Incorporated)
• Inventors: Shipley, William W.
• Primary Examiner(s): Gorenstein, Charles
• Application Number:
  US05/892,447
• Time in Patent Office: 445 Days
• Field of Search: 73/116, 73/119 R, 73/119 A, 73/117.3, 324/16 T
• US Class Current: 73/114.63
• CPC Class Codes: F02B 1/04 with fuel-air mixture admission into cylinder
• CPC Class Codes: G01M 15/06 by monitoring positions of pistons or cranks
• CPC Class Codes: G01M 15/09 by monitoring pressure in fluid ducts, e.g. in lubrication or cooling parts
• CPC Class Codes: G01P 3/481 of pulse signals

Abstract

A method is provided for dynamically timing an apparatus which includes cyclically generating reference and timing pulses. The method also includes counting the number of reference pulse per generating cycle; measuring a first timing fraction between a leading edge of the first timing pulse and a leading edge of the preceding reference pulse; measuring a second timing fraction between a leading edge of the second timing pulse and a leading edge of the preceding reference pulse; counting the number of whole reference pulses between the leading edges of the timing pulses; subtracting the first timing fraction from the count; and adding the second timing fraction to the count and producing a timing measurement.

Claims

1. In a method for dynamically timing an apparatus which includes cyclically generating reference signal pulses and at least first and second timing pulses, the improvement comprising:

counting the number of pulses of the reference signal for a generating cycle;

measuring the time between a leading edge of the first timing pulse and a leading edge of the preceding reference pulse, dividing by the period of the reference pulse, and producing a first timing fraction;

measuring the time between a leading edge of the second timing pulse and a leading edge of the preceding reference pulse, dividing by the period of the reference pulse, and producing a second timing fraction;

counting the number of whole reference pulses between the leading edges of the first and second timing pulses;

subtracting the first timing fraction from the count; and

adding the second timing fraction to the count and producing a timing measurement in reference signal pulses.

2. A method, as set forth in claim 1, including

dividing the timing measurement by the total number of reference signal pulses per generating cycle, multiplying by 360 and producing a timing measurement in degrees of the generating cycle.

3. A method, as set forth in claim 1, including adding the timing measurement in reference signal pulses to the preceding 31 timing measurements, dividing by 32 and producing an average timing measurement in reference signal pulses.

4. A method for digitally, dynamically timing an engine, comprising:

connecting a transducer to a toothed flywheel of the engine and generating reference pulses in response to movement of the flywheel teeth;

generating at least first and second timing pulses;

counting the number of teeth on the flywheel;

measuring the time between a leading edge of the first timing pulse and a leading edge of the preceding reference pulse, dividing by the period of the reference pulse, and producing a first timing fraction;

measuring the time between a leading edge of the second timing pulse and a leading edge of the preceding reference pulse, dividing by the period of the reference pulse, and producing a second timing fraction;

counting the number of whole reference pulses between the leading edges of the first and second timing pulses;

subtracting the first timing fraction from the count; and

adding the second timing fraction to the count and producing a timing measurement in numbers of flywheel teeth.

5. A method as set forth in claim 4, including dividing the timing measurement by the total number of flywheel teeth, multiplying by 360 and producing a timing measurement in degrees of flywheel rotation.

6. A method, as set forth in claim 4, including adding the timing measurement in flywheel teeth to the preceding 31 timing measurements in flywheel teeth, dividing by 32 and producing an average timing measurement in flywheel teeth.