US4829852A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system for an automatic transmission
Assignee: Subaru Corp
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Filing: 1988-03-02
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Granted: 1989-05-16
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Expires: 2008-03-02
Abstract
Abstract A control system for an automatic transmission having a first gear hold range, and a second gear hold range. A detector is provided for detecting a selected gear hold range and for producing a gear hold signal, and a sensing device is provided for producing an engine speed signal dependent on engine speed. When the engine speed signal exceeds a predetermined speed under the selection of one of gear hold ranges, the gear hold range is released and transmission is upshifted.
Inventors
- 👤 Ryuzo Sakakiyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:35
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/02; F16H61/0202; F16H61/0204; F16H61/0213; F16H59/00; F16H59/02; F16H59/08; F16H2059/082; F16H61/16; F16H2061/166; F16H61/10; F16H61/21; F16H61/68; F16H61/684; F16H61/686
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
104 words
A control system for an automatic transmission for a motor vehicle driven by an engine, the automatic transmission having a gear hold range, the control system comprising: detector means for detecting a selected gear hold range and for producing a gear hold signal; sensing means for detecting engine speed and for producing an engine speed signal dependent on engine speed; deciding means for producing an excessive engine speed signal when the detected engine speed exceeds a predetermined speed; control means responsive to the gear hold signal and to the excessive engine speed signal for releasing the gear hold range and for upshifting the transmission.
Claim 2
Dependent Claim
104 words
A control system for an automatic transmission for a motor vehicle driven by an engine, the automatic transmission having a gear hold range, the control system comprising: detector means for detecting a selected gear hold range and for producing a gear hold signal; sensing means for detecting engine speed and for producing an engine speed signal dependent on engine speed; deciding means for producing an excessive engine speed signal when the detected engine speed exceeds a predetermined speed; control means responsive to the gear hold signal and to the excessive engine speed signal for releasing the gear hold range and for upshifting the transmission.
Claim 3
Dependent Claim
23 words
The control system according to claim 1 wherein the gear hold range includes a first gear hold range and second gear hold range.
Claim 4
Dependent Claim
34 words
The control system according to claim 1 wherein the control means includes at least one shift valve having a spool, and a solenoid operated valve for shifting the spool for holding a gear range.
References Cited (Backward Citations)
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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) | 1992-05-15 | 1992-11-14 | 1993-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-05-15 | 1996-11-14 | 1997-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-05-15 | 2000-11-14 | 2001-05-16 | $7700.00 | Window Closed / Lapsed |