EP0029290A2
Expired / Lapsed
EP
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Transmission controls
Assignee: Motors Liquidation Co
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Filing: 1980-09-25
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Granted: —
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Expires: 2000-09-25
Abstract
Abstract An electro-hydraulic control for a power transmission has a solenoid-controlled valve (22) controlling a torque converter clutch (40), and a hydraulic-controlled valve (46) controlling a friction clutch or brake (58) which is effective to establish a drive ratio in the transmission. When a ratio change occurs, involving disengagement of the clutch or brake, the exhaust fluid therefrom operates on an electrical switch (62) which is effective to provide momentary disengagement of the torque converter clutch, with timed re-engagement of the torque converter clutch being under the control of a restricted-exhaust (64, 66) in conjunction with a pressure control valve (54).
Inventors
- 👤 Michael Leo Duhaime
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 15:15
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/14; F16H61/143; F16H47/00; F16H47/06; F16H47/08
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
204 words
A transmission control for a first friction drive-establishing means (40) controlled by an electrically- operated solenoid valve (22), and a second friction drive-establishing means (58) controlled by a hydraulically- operated shift valve (46), characterized by a control valve (54) having a differential-area valve spool (84) slidably disposed in a stepped valve bore (79), a passage means (60) interconnecting the hydraulically operated shift valve and the differential area (91) of- the valve spool, a restricted exhaust (64, 66) connected to the passage means, and pressure-responsive electrical switch means (62) connected to the passage means upstream of the restricted exhaust and pressure-actuable to cause the solenoid valve to effect disengagement of the first friction drive-establishing means (40), the passage means being effective to provide in co-operation with the valve spool and the restricted exhaust, a controlled pressure outlet for the second drive-establishing means (58) such that on disengagement of the second drive-establishing means the pressure in the passage means is initially increased sufficiently to actuate the switch means and after a predetermined time the pressure in the passage means is reduced by way of the restricted exhaust to permit the switch means to return to an unactuated condition for re-engagement of the first friction drive-establishing means.
Claim 2
Dependent Claim
204 words
A transmission control for a first friction drive-establishing means (40) controlled by an electrically- operated solenoid valve (22), and a second friction drive-establishing means (58) controlled by a hydraulically- operated shift valve (46), characterized by a control valve (54) having a differential-area valve spool (84) slidably disposed in a stepped valve bore (79), a passage means (60) interconnecting the hydraulically operated shift valve and the differential area (91) of- the valve spool, a restricted exhaust (64, 66) connected to the passage means, and pressure-responsive electrical switch means (62) connected to the passage means upstream of the restricted exhaust and pressure-actuable to cause the solenoid valve to effect disengagement of the first friction drive-establishing means (40), the passage means being effective to provide in co-operation with the valve spool and the restricted exhaust, a controlled pressure outlet for the second drive-establishing means (58) such that on disengagement of the second drive-establishing means the pressure in the passage means is initially increased sufficiently to actuate the switch means and after a predetermined time the pressure in the passage means is reduced by way of the restricted exhaust to permit the switch means to return to an unactuated condition for re-engagement of the first friction drive-establishing means.
Claim 3
Dependent Claim
72 words
A transmission control according to claim 1, characterized in that the differential-area valve spool (84) of the control valve (54) is movable against a bias (90) by pressure in the passage means (60) to provide a controlled connection between the passage means and an exhaust (92), and thereby limit the pressure within the passage means to a predetermined value in excess of that required for actuation of the electrical switch means (62).
Claim 4
Dependent Claim
85 words
A transmission control according to claim.2, characterized in that the passage means (60) is connected to a stepped bore (79) of the control valve (54) between differential-area lands (86 and 88) of the control valve, and a manually operable valve (28) is actuable to provide manual control of the second friction drive-establishing means (58) and additionally supply a control pressure (52) to the control valve to move the valve spool (84) thereof to a position establishing a connection between the passage means and exhaust (92).
Claim 5
Dependent Claim
30 words
A transmission control according to any one of claims 1 to 3, characterized in that the first and second friction drive-establishing means (40 and 58) comprise.first and .second friction clutches.
Claim 6
Dependent Claim
34 words
A transmission control according to any one of claims 1 to 3, characterized in that the first and second friction drive-establishing means (40 and 58) comprise a friction clutch and a friction brake respectively.
Claim 7
Dependent Claim
45 words
A transmission control according to any one of claims 1 to 3, characterized in that the first friction drive-estabishing means comprises a torque. converter lock-up clutch (40) and the second friction drive-establishing means comprises a friction device (58) effective to establish a transmission drive ratio.
References Cited (Backward Citations)
No citation records indexed.
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