US3683870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel injection systems
Assignee: Petrol Injection Ltd
•
Filing: 1970-06-15
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Granted: 1972-08-15
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Expires: 1990-06-15
Abstract
Abstract A fuel injection system in which fuel flow through the injector nozzles is controlled by electrically operable interrupter valves. Electrical pulses to operate the interrupter valves are generated at constant frequency and the length of the pulses is varied with an engine operating parameter, for example engine air intake. Suitable pulse generating circuits and an arrangement for varying the pulse length with air intake are described.
Inventors
- 👤 Harold Ernest Jackson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:27
CPC Classifications
F; F02; F02M; F02M69/00; F02M69/44; F02D; F02D41/00; F02D41/30; F02D41/32; F02M51/00; F02M51/02; F02M51/06; F02M51/061; F02M51/0625; F02M51/0664; F02M51/0667; F02M51/08; F02M69/14; F02M69/145; F02M69/30; F02M69/36; F02M69/40
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
143 words
A fuel injection system for an internal combustion engine, including a source of fuel under pressure, a fuel flow path, at least one fuel injector nozzle connected to receive fuel from the fuel flow path, at least one electrically operable fuel interrupter valve actuable to control fuel flow through the injector nozzle(s), and an electrical control circuit arrangement operable to generate electricAl operating pulses at a continuous constant frequency independent of engine operation and connected to apply said pulses to the interrupter valve(s) to actuate the interrupter valves(s), said control circuit arrangement including means electrically connected in said circuit arrangement and responsive to at least one engine operating parameter to adjust the length of said operating pulses, and thereby adjust the period of time for which the or each interrupter valve is actuated, in response to variations in the said engine operating parameter(s).
Claim 2
Dependent Claim
143 words
A fuel injection system for an internal combustion engine, including a source of fuel under pressure, a fuel flow path, at least one fuel injector nozzle connected to receive fuel from the fuel flow path, at least one electrically operable fuel interrupter valve actuable to control fuel flow through the injector nozzle(s), and an electrical control circuit arrangement operable to generate electricAl operating pulses at a continuous constant frequency independent of engine operation and connected to apply said pulses to the interrupter valve(s) to actuate the interrupter valves(s), said control circuit arrangement including means electrically connected in said circuit arrangement and responsive to at least one engine operating parameter to adjust the length of said operating pulses, and thereby adjust the period of time for which the or each interrupter valve is actuated, in response to variations in the said engine operating parameter(s).
Claim 3
Dependent Claim
33 words
A system as claimed in claim 1, in which the control circuit arrangement is operable to generate the operating pulses to open the interrupter valve(s) to permit fuel flow through the injector nozzle(s).
Claim 4
Dependent Claim
50 words
A system as claimed in claim 1, in which the control circuit arrangement is an astable multivibrator circuit including at least one resistive component which is responsive to the said one engine operating parameter and is adjustable in response to variations in that parameter to adjust the operating pulse length.
Claim 5
Dependent Claim
83 words
A system as claimed in claim 1, in which the control circuit arrangement includes a reference voltage generator operable to generate a reference voltage which varies periodically with time, a control signal generator operable to generate a control signal which varies in response to variations in the said one engine operating parameter, and an operating pulse generator responsive to the reference voltage and the control signal to generate an operating pulse when the reference voltage bears a predetermined relationship to the control signal.
Claim 6
Dependent Claim
65 words
A system as claimed in claim 4, in which the reference voltage generator is a sawtooth waveform generator and the control signal generator is operable to generate a bias voltage the level of which varies in response to variations in the said one engine operating parameter, the operating pulse generator being operable to generate an operating pulse when the reference voltage exceeds the bias voltage.
Claim 7
Dependent Claim
37 words
A system as claimed in claim 4, in which the control signal generator includes means operable to generate an oscillating voltage the amplitude of which varies in response to variations in the said one engine operating parameter.
Claim 8
Dependent Claim
45 words
A system as claimed in claim 6, in which the oscillating voltage generator includes an inductive component which is responsive to the said one engine operating parameter and is adjustable in response to variations in that parameter to vary the amplitude of the oscillating voltage.
Claim 9
Dependent Claim
19 words
A system as claimed in claim 1, in which the said one engine operating parameter is engine air intake.
Claim 10
Dependent Claim
63 words
A system as claimed in claim 8, including an engine air intake responsive mechanism operable to produce a control pressure differential in the engine air supply path and adjustable to maintain the control pressure differential at a substantially constant value, the control circuit arrangement being operable to adjust the interrupter valve actuation period in response to adjustment of the air intake responsive mechanism.
Claim 11
Dependent Claim
32 words
A system as claimed in claim 1, including a fuel pressurizing device connected in the fuel flow path and operable to pressurize fuel in dependence on at least one engine operating parameter.
Claim 12
Dependent Claim
19 words
A system as claimed in claim 10, in which the said one engine operating parameter is engine air intake.
Claim 13
Dependent Claim
68 words
A system as claimed in claim 11, including an engine air intake responsive mechanism operable to produce a control pressure differential in the engine air supply path and adjustable to maintain the control pressure differential at a substantially constant value, the fuel pressurizing device being operable to vary the pressure at which fuel flows to the injector nozzle(s) in response to adjustment of the air intake responsive mechanism.
Claim 14
Dependent Claim
24 words
A system as claimed in claim 1, including a plurality of interrupter valves each actuable to control fuel flow through a respective injector nozzle.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-15 | 1976-02-14 | 1976-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-15 | 1980-02-14 | 1980-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-15 | 1984-02-14 | 1984-08-15 | $7700.00 | Window Closed / Lapsed |