EP0044656A1
Expired / Lapsed
EP
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Method of and apparatus for optimising the operation of an internal combustion engine
Assignee: ZF International UK Ltd
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Filing: 1981-07-07
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Granted: —
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Expires: 2001-07-07
Abstract
Abstract I.C. engine performance is optimised by imposing a cyclically fluctuating trim on a control input in synchronism with engine operation and measuring the effect of the trim on engine speed. A store (16) holds an average value of the control input (e.g. spark timing) and the trim is applied by a calculator circuit 14 to increment and decrement the counter content periodically in synchronism with the engine. A counter (18) counts clock pulses in a sequence which yields a residual count enabling the content of the store (16) to be changed if this residual count indicates that advancing or retarding timing will increase engine speed.
Inventors
- 👤 Paul Anthony Harris
- 👤 Andrew Peter Toller
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 11:50
CPC Classifications
F; F02; F02P; F02P5/00; F02P5/04; F02P5/145; F02P5/1455; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/40
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
81 words
1 . A method of optimising the operation of an internal combustion engine by varying an engine control input which controls cyclically occurring engine events to obtain maximum engine speed in prevailing conditions, comprising establishing an average value for said control input, imposing a cyclically fluctuating trim on said control input in synchronism with the engine events, measuring the effect of the trim on the engine speed over a cycle thereof and adjusting said average value in accordance with such measurement.
Claim 2
Dependent Claim
81 words
1 . A method of optimising the operation of an internal combustion engine by varying an engine control input which controls cyclically occurring engine events to obtain maximum engine speed in prevailing conditions, comprising establishing an average value for said control input, imposing a cyclically fluctuating trim on said control input in synchronism with the engine events, measuring the effect of the trim on the engine speed over a cycle thereof and adjusting said average value in accordance with such measurement.
Claim 3
Dependent Claim
72 words
A method as claimed in claim 1 in which said cyclically fluctuating trim consists of allowing the engine to run for two revolutions with the control input at the established average value for two revolutions with the control input changed in one direction from the established average value, for two revolutions at the established average value again and finally for two further revolutions with the control input changed in the opposite direction.
Claim 4
Dependent Claim
72 words
A method as claimed in claim 2 in which measurement of the effect of the trim on engine speed is carried out by counting fixed frequency pulses in one direction for said first-mentioned two engine revolutions, in the opposite direction for the next four engine revolutions and in the original direction for the final two revolutions, the residual count indicating whether the engine speed can be increased by changing said control input.
Claim 5
Dependent Claim
45 words
A method as claimed in claim 2 or claim 3 in which the control input determines the timing of spark ignition with respect to engine shaft position, ignition being advanced in the second period of two engine revolutions and retarded in the fourth such period.
Claim 6
Dependent Claim
30 words
A method as claimed in claim 2 or claim 3 in which the control input determines the position of an air input valve so as to vary the fuel/air ratio.
Claim 7
Dependent Claim
78 words
Engine control apparatus comprising control means having a control input and operating to control cyclically occurring engine events, store means for storing a signal corresponding to an average value of a control signal for application to said control input, means for superimposing a cyclically varying trim signal varying in synchronism with the engine-events, and means for detecting the effect of said trim signal on the engine speed and operating to change the signal stored in the store means.
Claim 8
Dependent Claim
78 words
Engine control apparatus comprising control means having a control input and operating to control cyclically occurring engine events, store means for storing a signal corresponding to an average value of a control signal for application to said control input, means for superimposing a cyclically varying trim signal varying in synchronism with the engine-events, and means for detecting the effect of said trim signal on the engine speed and operating to change the signal stored in the store means.
Claim 9
Dependent Claim
56 words
Apparatus as claimed in claim 6 in which the control means controls spark ignition timing and the store means comprises a counter connected to said effect detecting means so as to have its content changed thereby in accordance with the effect detected, the counter content determining the timing of spark ignition relative to engine shaft position.
Claim 10
Dependent Claim
52 words
Apparatus as claimed in claim 7 in which said means for superimposing a cyclic trim operates to increment the counter content in one period of operation and to decrement the counter content in another period, such periods being separated by periods in which the counter content is at its established average value.
Claim 11
Dependent Claim
109 words
Apparatus as claimed in claim 8 in which the effect detecting means comprises a clock pulse source, a further reversible counter connected to said clock pulse source so as to count pulses therefrom and means controlling the direction of counting such that said further counter counts in one direction in a first period of average timing, in the opposite direction during a following period of advanced timing and a following period of average timing and in the original direction during a final period of retarded timing, the residual count at the end of the cycle of four periods determining any adjustment of the content of the first mentioned counter.
References Cited (Backward Citations)
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