Abstract: A transmission system for transmitting power from an engine to the driving wheels of a tractor. The system includes a multiple ratio mechanical range transmission coupled to a speed transmission via a manually operable master clutch. A high slip fluid coupling is used to couple the speed transmission to the engine. The coupling includes a lockup clutch engageable and disengageable under predetermined conditions and sequential order with other clutches.

Abstract: A transmission system particularly useable for transmitting power from an internal combustion engine to the driving wheels of a vehicle such as a tractor. The system includes a multiple ratio mechanical range transmission coupled to a speed transmission via a manually operable master clutch. A high slip fluid coupling is used to couple the speed transmission to the engine, and an electronically controlled lockup clutch locks the impeller of the fluid coupling to the output turbine of same when the speed of the engine exceeds a first predetermined speed, and maintains the coupling locked until the speed of the engine drops below a second substantially lower predetermined speed; the difference between the predetermined speeds is due to a speed comparator hysteresis which serves to prevent hunting during automatic gear shifts between different ratios.

Abstract: A motor vehicle transmission comprising a speed and range sections connected via a master clutch, provides all speed selections on-the-go, i.e. without stopping the motor vehicle. An engine driven input shaft extending through the speed transmission section carries a pair of drive clutch packs for power shifting of the speeds. The power shifting between the clutch packs on this shift requires no master clutch engagement or disengagement. The plurality of speed which are not power shifted engage via gear synchronizers which require the disengagement of the master clutch while vehicle is still on-the-go. The disengagement of the master clutch simultaneously disengages the clutches in the drive clutch pack and is sequenced in such a manner that re-engagement of the master clutch follows the re-engagement of the drive clutch packs.

Abstract: A transmission system particularly usable for transmitting power from an internal combustion engine to the driving wheels of a vehicle such as a tractor includes a multiple ratio mechanical range transmission coupled to an infinitely variable ratio hydromechanical transmission via a manually operable master clutch. A high slip fluid coupling is used to couple the hydromechanical transmission to the engine, and an electronically controlled lockup clutch locks the impeller of the fluid coupling to the output turbine when the speed of the engine exceeds a first predetermined speed, and maintains the coupling locked until the speed of the engine drops below a second substantially lower predetermined speed.

Abstract: The operational speed of a fluid drive unit in a hydromechanical transmission is limited by means of an overspeed preventing, one-way clutch establishing a positive drive connection between torque transmitting elements of the hydromechanical transmission. Two power paths are established between the planetary gear unit and the input shaft of the transmission to drive an output shaft at a variable drive ratio controlled by a variable displacement type of fluid drive unit. One of the power paths is established through fixed ratio gearing while the other power path is established through the fluid drive units while operating within a speed ratio range limited by the one-way clutch.