Patent US5088356A successfully refreshed from Google Patents.
US5088356A
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Automatic transmission hydraulic control system
Assignee: Aisin Corp
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Filing: 1990-10-01
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Granted: 1992-02-18
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Expires: 2010-10-01
Abstract
Abstract An automatic transmission control system includes a shift valve having a valve body, a spool, a sleeve, a plunger and a return spring. An area of the plunger is acted on by a throttle pressure and is smaller than an area of a land acted on by the throttle pressure. Accordingly, the spool is movable against the throttle pressure to make a upshift when the governor pressure is over a predetermined value in relation to the throttle pressure.
Inventors
- 👤 Shigeo Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 06:12
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/02; F16H61/0262; F16H61/0265; F16H61/0267
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
144 words
An automatic transmission control system comprising: a shift valve, a valve body, a valve spool in said valve body and having a land urged by a throttle pressure in a predetermined direction, a sleeve disposed in said valve body at an end of said spool, a plunger disposed in said sleeve and in contact with said end of said spool, a return spring disposed between said plunger and said sleeve and compressed by said throttle pressure acting on said plunger and by a governor pressure acting on said spool and said plunger, and an area of said plunger acted on by said throttle pressure being smaller than an area of said land acted on by said throttle pressure, whereby said spool moves against said throttle pressure to upshift said transmission when said governor pressure exceeds a predetermined value in relation to said throttle pressure.
Claim 2
Dependent Claim
144 words
An automatic transmission control system comprising: a shift valve, a valve body, a valve spool in said valve body and having a land urged by a throttle pressure in a predetermined direction, a sleeve disposed in said valve body at an end of said spool, a plunger disposed in said sleeve and in contact with said end of said spool, a return spring disposed between said plunger and said sleeve and compressed by said throttle pressure acting on said plunger and by a governor pressure acting on said spool and said plunger, and an area of said plunger acted on by said throttle pressure being smaller than an area of said land acted on by said throttle pressure, whereby said spool moves against said throttle pressure to upshift said transmission when said governor pressure exceeds a predetermined value in relation to said throttle pressure.
Claim 3
Dependent Claim
29 words
An automatic transmission control system according to claim 1, wherein pressure from a manual valve is selectively supplied to said shift valve to urge said plunger in said direction.
Claim 4
Dependent Claim
27 words
An automatic transmission control device according to claim 2, wherein said pressure from said manual valve supplied to said sleeve to urge said plunger in said direction.
Claim 5
Dependent Claim
14 words
An automatic transmission control device according to claim 2, wherein said sleeve is movable.
Claim 6
Dependent Claim
14 words
An automatic transmission control device according to claim 2, wherein said sleeve is fixed.
References Cited (Backward Citations)
US4566355A
Cited
US4944201A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-02-17 | 1995-08-19 | 1996-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-02-17 | 1999-08-19 | 2000-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-02-17 | 2003-08-19 | 2004-02-18 | $7700.00 | Window Closed / Lapsed |