摘要 |
An electronically controlled hydrodynamic retarder (18) interconnects with the output shaft (16) of a vehicle transmission (12) to selectively apply a braking torque thereto. The retarder includes a solenoid valve, the operating duty cycle of which controls the retarder capacity and resultant braking torque. A control unit (20), interconnecting the transmission and the retarder, regulates the duty cycle of the solenoid valve to regulate the retarder operation as a function of excessive deceleration or overheating, while also regulating such operation during downshift to assure efficient, effective, and comfortable operation of the transmission/retarder. The retarder is adaptive to accommodate variations resulting from age, wear, and the like. <IMAGE> |