Abstract: An in-line transmission provides 26 useful speeds, including 19 forward speeds and 7 reverse speeds. The transmission includes a main planetary having three sets of planetary gears, as well as a separate hi-lo planetary. At least the first and second sets of planetary gears on the main planetary carrier are formed of double gears. Each side of the first set of double gears has its own ring gear which is independently brakable relative to the housing and its own sun gear. Drive from the input shaft to these two sun gears is provided along two main paths, one direct and the other through the hi-lo planetary. One side of the second set of double gears also has an independently brakable ring gear, as well as a sun gear connected to the output shaft. However, the other side of the second set of double gears meshes only with the third set of planetary gears, which preferably are single gears.

Abstract: The oil level is controlled between the main gear shift chamber of a transmission and the final reduction gearing/differential chamber by pumping air from the differential chamber into the main gear chamber. The increased air pressure then forces oil back into the differential chamber. The air pump preferably is a simple piston pump driven by a cam on one of the drive shafts on the main transmission chamber. An oil film is provided in the passage connecting the main transmission chamber to allow flow of oil between those chambers, while preventing the flow of air.

Abstract: An improved self-energized synchronizer for bringing two rotatable members which are aligned about a common axis into synchronization. The synchronizer includes a body member carried on the first rotatable member which in turn engages with an annular shifter collar. Positioned adjacent to the shifter collar is an axially movable annular blocking ring having a frictional surface. Situated on the other side of the blocking ring, opposite the body member, is a drive collar which is rotatably fixed to the second rotatable member. The improvement to the synchronizer includes a frictional disk and a self-energized mechanism for transferring frictional torque between the first and second rotatable members. The self-energized mechanism is positioned for engagement with the blocking ring, while the frictional disk is positioned between the drive collar and the self-energized mechanism.

Abstract: A tractor transmission is synchronized between four different speeds in each of two different high and low ranges and a reverse range. A top shaft coupled to be driven by the tractor engine has four different gears which are concentrically and rotatably spaced along the length thereof in constant mesh with a different one of a second group of four gears formed on the outer surface of a counter shaft. The counter shaft is selectively coupled to the top shaft by either of two pairs of synchronizers concentrically mounted on the top shaft between different pairs of the first four gears. High and low ranges are respectively provided by a first splined collar capable of coupling the counter shaft directly to a differential drive shaft and a second splined collar capable of coupling the differential drive shaft to the fourth gear disposed about the top shaft via a low range driven gear.

Abstract: A hydraulically operated control arrangement for a transmission includes a spring-loaded pressure regulating valve which slides into a position to cut off an exit chamber for hydraulic fluid from an input chamber for pressurized hydraulic fluid so as to route the incoming hydraulic fluid exclusively to the transmission for various control and lubricating functions when hydraulic fluid pressure in the input chamber falls below a first threshold value. Hydraulic fluid applied to the input chamber continues to feed a first plurality of functions within the transmission via the input chamber and a second plurality of functions in the transmission via an intermediate chamber disposed between the input and exit chambers and in communication with the pressure regulating valve until such time as the hydraulic fluid pressure at the input chamber drops below a second threshold value so as to permit the pressure regulating valve to cut off the intermediate chamber from the input chamber.