Abstract: A vehicle automatic transmission including a torque converter and a multiple stage transmission gear mechanism. The gear mechanism is controlled through a hydraulic system having solenoid valves. An electronic control unit is provided to control the hydraulic system under a shift control map having shift up and shift down control lines. The shift down control line is determined in terms of the torque converter turbine speed and the engine throttle valve position as a line in which the torque converter is operated with a torque ratio of substantially one.

Abstract: A versatile transmission, particularly a test stand transmission, in which internally and/or externally toothed conversion elements can be inserted from the outside to transmit torque from gears driven by one or more input shafts to one or more output shafts.

Abstract: A transmission, especially for use with small tractors and the like, provides a number of higher speed drives, typically associated with mowing, and a number of extremely slow "creep" speed drives to make said tractor more compatible with snow blower and tiller implements. All speed drives are available in a single range with each being selected sequentially by movement of a single gearshift lever. A unique reduction train exploits one or more higher speed drives to drive the "creep" speed pinions and a safer reverse speed drive at reduced rotational speed. The extremely wide speed ratio range will also dismiss the smallest pinions and severe speed increasing drives presently employed in these transmissions to greatly increase capacity and to reduce costs.