Patent ID: 6110071
Filing Date: 2000-08-29
Classification: F16H,Y10T

Abstract:
A transmission control for a transmission having a drive circuit and a reverse circuit, said control comprising:a selectively energizable forward solenoid valve;a selectively energizable reverse solenoid valve;a forward disable valve means for controlling pressure distribution to said drive circuit;a reverse disable valve means for controlling pressure distribution to said reverse circuit;a single mode valve element having a forward drive circuit position, a reverse drive circuit position and a neutral circuit position, said mode valve element being selectively disposed in fluid flow relation between a pressure source and both said forward disable valve means and said reverse disable valve means for distributing fluid from said source to said disable valve means in response to being positioned by said solenoid valve means;said forward disable valve means being operable to exhaust said drive circuit in response to a signal from said reverse solenoid valve, said reverse disable valve means being operable to exhaust said reverse circuit in response to a signal from said forward solenoid valve, and said forward and reverse disable valve means cooperating to prevent the simultaneous engagement of said drive circuit and said reverse circuit; anda latching passage communicating fluid pressure in said drive circuit from downstream of said forward disable valve means to said mode valve element to prevent a state change thereof unless commanded by an operator.