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US 4,314,487 AGranted
Braking method for vehicle transmission
AssigneeS.R.M. Hydromekanik Aktiebolag
InventorKarl G. Ahlen
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AssigneeS.R.M. Hydromekanik Aktiebolag
InventorKarl G. Ahlen
Estimating the term…
A method is provided for obtaining braking capacity from the engine-transmission unit of a hydromechanical vehicle transmission having a torque converter in combination with a plurality of mechanical gear steps. The braking force is provided by running the turbine member faster than the engine, either with the guide member of the torque conventer kept stationary or released so as to be free to rotate and with the torque converter's direct drive clutch released, and with the pump member of the torque converter connected to the rotating casing of the torque converter which is connected to the engine. The braking capacity is regulated by regulating the engine speed and changing the gear ratios. Regulation of the engine speed can be accomplished by throttling the exhaust or, under other circumstances, by causing the engine to rotate faster.
A method for braking a vehicle with an engine operatively connected to a transmission which comprises a torque converter having a pump member, a guide member and a turbine member, and a multi-step mechanical gear transmission in series with the torque converter, the multi-step transmission being downstream from the torque converter with the turbine member being connected to the input of the said multi-step transmission, and the output of the multi-step transmission being operatively connected to the road wheels of the vehicle, said method comprising driving the turbine member at a higher speed than the pump member with the sole driving connection from the vehicle road wheels to the pump member being via the turbine member through the torque converter, and with the pump member connected to rotate at the same speed as the engine, and regulating the braking effort by controlling the speed of the engine.
Dependencies are inferred from the claim text.