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U.S. Department of Energy
Office of Scientific and Technical Information

Control for automatic transmissions

Patent ·
OSTI ID:6999317

A control system is described for vehicle automatic transmissions. The system comprises a hydraulic actuator means for engaging friction engaging means for establishing a driving gear train, hydraulic conduit means for supplying hydraulic pressure to the hydraulic actuator means, and a control valve means provided in the hydraulic conduit means to connect the actuator means alternately to hydraulic source means and drain conduit means. The system also includes a pressure reducing valve means provided in the drain conduit means for producing a pressure which is lower than a pressure for making the friction engaging means engage, vehicle speed detecting means for detecting vehicle speed and producing a low vehicle speed signal showing that the vehicle speed is below a predetermined value, and position detecting means for detecting position of an engine power control member and producing a position signal when the control member is in a low engine output position smaller than a predetermined position.

Assignee:
Mazda Motor Corp., Hiroshima
Patent Number(s):
US 4618042
OSTI ID:
6999317
Country of Publication:
United States
Language:
English