Microprocessor Controls in Hydraulics - An Example

By use of an example, i.e., the application of a torque converter lock up clutch in a powershift transmission, this paper explores the use of microprocessors to control a hydro-mechanical system. Included is a method in which speeds and relative speeds of rotating gears can be determined, a method by which a solenoid operated control valve can be actuated by microprocessor control and a partial description of a microprocessor program which allows the application of a torque converter lock-up clutch when conditions warrant.