Patent US3669674A successfully refreshed from Google Patents.
Patent US3810531A successfully refreshed from Google Patents.
US3810531A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lock up clutch control
Assignee: Motors Liquidation Co
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Filing: 1972-09-05
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Granted: 1974-05-14
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Expires: 1992-09-05
Abstract
Abstract A control for a transmission having a fluid coupling and a lock up clutch for selectively providing a fluid or mechanical input from a gas turbine engine. A shift valve controls the engagement and disengagement of the lock up clutch in response to a transmission output governor signal or a manual signal in cooperation with the governor signal. The manual signal is controlled by a control valve which also supplies a disengagement bias pressure to the shift valve when the manual signal is not directed to the shift valve. The manual signal is generated in response to an engine operating parameter, such as torque demand, and acts on the shift valve in such a manner as to prevent engagement of the lock up clutch at zero vehicle speed above a predetermined value of the operating parameter.
Inventors
- 👤 J Edmunds
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:09
CPC Classifications
F; F16; F16D; F16D47/00; F16D47/06
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
143 words
A control for a clutch for an engine driven transmission comprising, a source of fluid pressure; governor means for supplying a transmission speed signal; modulator means for supplying an engine parameter signal; shift valve means operatively connected between said source and the clutch and being movable to first and second positions for controlling the engagement and disengagement respectively of the clutch including a first valve area in fluid communication with said governor means, a second valve land area, and a differential area; and control valve means operable to provide a bias pressure to said second valve land area to bias said shift valve means toward said second position and being selectively movable to communicate said engine parameter signal from said modulator means to said first differential area to bias said shift valve means toward said first position and to exhaust the bias pressure.
Claim 2
Dependent Claim
143 words
A control for a clutch for an engine driven transmission comprising, a source of fluid pressure; governor means for supplying a transmission speed signal; modulator means for supplying an engine parameter signal; shift valve means operatively connected between said source and the clutch and being movable to first and second positions for controlling the engagement and disengagement respectively of the clutch including a first valve area in fluid communication with said governor means, a second valve land area, and a differential area; and control valve means operable to provide a bias pressure to said second valve land area to bias said shift valve means toward said second position and being selectively movable to communicate said engine parameter signal from said modulator means to said first differential area to bias said shift valve means toward said first position and to exhaust the bias pressure.
Claim 3
Dependent Claim
221 words
A control for a lock up clutch for an engine driven transmission comprising, a source of fluid pressure; governor means for supplying a transmission speed signal; modulator means for supplying a variable engine parameter signal; shift valve means operatively connected between said source and the lock up clutch and being movable to first and second positions for controlling the engagement and disengagement respectively of the lock up clutch including a first valve area in fluid communication with said governor means, a second valve land area, a first differential area, and a second differential area; and control valve means operable to provide a bias pressure to said second valve land area to bias said shift valve means toward said second position which bias pressure is constant during one range of the engine parameter signal and varies with the engine parameter signal during another range and being selectively movable to communicate said engine parameter signal from said modulator means to said first differential area to bias said shift valve means toward said first position and to exhaust the bias pressure when said engine parameter signal is above a predetermined value, said second differential area being in fluid communication with said source when said shift valve means is in said first position to bias said shift valve means to remain in said first position.
Claim 4
Dependent Claim
221 words
A control for a lock up clutch for an engine driven transmission comprising, a source of fluid pressure; governor means for supplying a transmission speed signal; modulator means for supplying a variable engine parameter signal; shift valve means operatively connected between said source and the lock up clutch and being movable to first and second positions for controlling the engagement and disengagement respectively of the lock up clutch including a first valve area in fluid communication with said governor means, a second valve land area, a first differential area, and a second differential area; and control valve means operable to provide a bias pressure to said second valve land area to bias said shift valve means toward said second position which bias pressure is constant during one range of the engine parameter signal and varies with the engine parameter signal during another range and being selectively movable to communicate said engine parameter signal from said modulator means to said first differential area to bias said shift valve means toward said first position and to exhaust the bias pressure when said engine parameter signal is above a predetermined value, said second differential area being in fluid communication with said source when said shift valve means is in said first position to bias said shift valve means to remain in said first position.
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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) | 1977-05-13 | 1977-11-12 | 1978-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-13 | 1981-11-12 | 1982-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-13 | 1985-11-12 | 1986-05-14 | $7700.00 | Window Closed / Lapsed |