US4724818A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Intake air control system for an internal combustion engine
Assignee: Subaru Corp
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Filing: 1987-01-12
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Granted: 1988-02-16
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Expires: 2007-01-12
Abstract
Abstract A bypass is provided around a throttle valve of an engine, and a solenoid operated on-off control valve provided in the bypass so as to control flow of intake air. When the engine is accelerated in the coasting of a vehicle, an acceleration signal is produced. In response to the acceleration signal, a driving pulse train is fed to the control valve so as to reduce the intake air flow in dependence on coolant temperature of the engine by the coolant temperature.
Inventors
- 👤 Tomoya Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:35
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/02; F02D41/04; F02D41/10; F02D41/0002; F02D41/0007; F02D41/06; F02D41/068; F02D43/00; F02D9/00; F02D9/08; F02D9/10; F02D9/1035; F02D9/1055; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y02T10/40
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
115 words
An intake air control system for an internal combustion engine comprising: a bypass provided around a throttle valve of the engine; a control valve provided in the bypass so as to control flow of intake air; first means for detecting acceleration of the engine in idling condition of the engine, and for producing an acceleration signal; second means for detecting temperature of coolant of the engine and for producing a coolant temperature signal; and third means responsive to the acceleration signal for producing a drive signal for operating the control valve so as to reduce the intake air flow in dependence on the coolant temperature signal for a time decided by the coolant temperature signal.
Claim 2
Dependent Claim
115 words
An intake air control system for an internal combustion engine comprising: a bypass provided around a throttle valve of the engine; a control valve provided in the bypass so as to control flow of intake air; first means for detecting acceleration of the engine in idling condition of the engine, and for producing an acceleration signal; second means for detecting temperature of coolant of the engine and for producing a coolant temperature signal; and third means responsive to the acceleration signal for producing a drive signal for operating the control valve so as to reduce the intake air flow in dependence on the coolant temperature signal for a time decided by the coolant temperature signal.
Claim 3
Dependent Claim
25 words
The control system according to claim 1 wherein the control valve is a solenoid operated on-off valve, and the drive signal is a pulse train.
Claim 4
Dependent Claim
30 words
The control system according to claim 2 wherein duty ratio of the pulse train is decided in accordance with the coolant temperature signal and opening degree of the throttle valve.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-02-15 | 1991-08-17 | 1992-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-15 | 1995-08-17 | 1996-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-15 | 1999-08-17 | 2000-02-16 | $7700.00 | Window Closed / Lapsed |