US3661131A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Speed controls
Assignee: AE PLC
•
Filing: 1969-11-28
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Granted: 1972-05-09
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Expires: 1989-11-28
Abstract
Abstract The invention relates to speed control systems for controlling the rotational speed of an internal combustion engine and provides means for controlling the engine utilizing a fuel injection system idling speed so as to maintain it at a substantially constant pre-selected value which is virtually independent of ambient conditions and engine load conditions. Different types of valve means are described for controlling the flow of air from a point at substantially atmospheric pressure to a point downstream of the engine throttle valve. Control circuits are also described for controlling the valve means in accordance with the difference between a pre-selected value of engine idling speed and the actual engine idling speed.
Inventors
- 👤 Brian Hugh Croft
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:17
CPC Classifications
F; F02; F02M; F02M3/00; F02M3/06; F02M3/07; F02D; F02D31/00; F02D31/001; F02D31/002; F02D31/003; F02D31/005; F02M3/075; F02D11/00; F02D11/06; F02D11/10; F02D2011/101; F02D2011/102
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
178 words
An idling speed control system for an internal combustion engine having an inlet manifold, a main engine throttle valve disposed in the inlet manifold for controlling the flow of motive fluid therethrough, and a fuel injection system responsive to manifold pressure and engine speed, said system comprising electrically operable valve means for controlling the flow of motive fluid from a point at substantially atmospheric pressure to a point in the inlet manifold downstream of the main engine throttle valve but upstream of said fuel injection system, selector means for producing a first electrical signal representative of a pre-selected value of engine idling speed, means for producing a second electrical signal representative of actual engine speed and a comparator device connected to receive the first and second signals and arranged to produce an electrical output signal representative of the difference therebetween, said output signal being applied to the electrically operable valve means to control the operation thereof, whereby to maintain the engine idling speed substantially constant at said pre-selected value virtually independently of ambient conditions and engine load conditions.
Claim 2
Dependent Claim
178 words
An idling speed control system for an internal combustion engine having an inlet manifold, a main engine throttle valve disposed in the inlet manifold for controlling the flow of motive fluid therethrough, and a fuel injection system responsive to manifold pressure and engine speed, said system comprising electrically operable valve means for controlling the flow of motive fluid from a point at substantially atmospheric pressure to a point in the inlet manifold downstream of the main engine throttle valve but upstream of said fuel injection system, selector means for producing a first electrical signal representative of a pre-selected value of engine idling speed, means for producing a second electrical signal representative of actual engine speed and a comparator device connected to receive the first and second signals and arranged to produce an electrical output signal representative of the difference therebetween, said output signal being applied to the electrically operable valve means to control the operation thereof, whereby to maintain the engine idling speed substantially constant at said pre-selected value virtually independently of ambient conditions and engine load conditions.
Claim 3
Dependent Claim
106 words
A system as claimed in claim 1, wherein the electrically operable valve means comprises first and second chambers each having a respective outlet which is adapted to be connected to the inlet manifold downstream of the main engine throttle valve, a diaphragm separating said chambers and caRrying a valve member which co-operates with a valve seat to control the admission of motive fluid at substantially atmospheric pressure to the first chamber, a conduit for establishing restricted communication between said first and second chambers, and an electrically operable valve connected to the outlet of the second chamber for controlling the pressure therein, whereby to influence said diaphragm.
Claim 4
Dependent Claim
32 words
A system as claimed in claim 1, wherein the motive fluid at substantially atmospheric pressure is derived from a point in the induction system of the engine upstream of the throttle valve.
Claim 5
Dependent Claim
16 words
A system as claimed in claim 1, wherein said valve means comprises a solenoid operated valve.
Claim 6
Dependent Claim
16 words
A system as claimed in claim 1, wherein said valve means comprises a motor driven valve.
Claim 7
Dependent Claim
34 words
A system as claimed in claim 5, wherein the motor driven valve directly controls the admission of motive fluid to the induction system of the engine at a point downstream of the throttle valve.
Claim 8
Dependent Claim
43 words
A system as claimed in claim 1, wherein the second signal representative of actual engine speed is a voltage signal derived from a tachometer generator driven by the engine and the first signal representative of the required idling speed is a reference voltage.
Claim 9
Dependent Claim
13 words
A system as claimed in claim 7, wherein the voltages are D.C. voltages.
Claim 10
Dependent Claim
39 words
A system as claimed in claim 8, wherein the comparator device is an operational amplifier whose output is applied to a level detector circuit which produces an output employed to control the operation of a solenoid operated valve means.
Claim 11
Dependent Claim
16 words
A system as claimed in claim 9, wherein the level detector is a further operational amplifier.
Claim 12
Dependent Claim
36 words
A system as claimed in claim 8, wherein the comparator device is an operational amplifier whose output is fed to a second operational amplifier producing an output which controls an electric motor driving the valve means.
References Cited (Backward Citations)
US2499263A
Cited
US2827910A
Cited
US2755786A
Cited
US2911077A
Cited
US2971596A
Cited
US3252539A
Cited
US3310044A
Cited
US3511329A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-09 | 1975-11-08 | 1976-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-09 | 1979-11-08 | 1980-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-09 | 1983-11-08 | 1984-05-09 | $7700.00 | Window Closed / Lapsed |