Multi-range synchronized transmission and housing therefor

Abstract

A collar shift type transmission is arranged to provide an increased number of speed changes from a reduced number of gears and shafts. The transmission has a main shaft, an output shaft and two intermediate shafts with a plurality of intermeshing gear sets located about each shaft. Collar shift elements for engaging different gears to provide a multiplicity of speed and range changes are provided only on the main shaft and one intermediate shaft. Arrangement of the gears of each set in pairs maximizes the number of gear changes while minimizing the required number of gears, collar shift elements and control mechanisms. The main shaft preferably is provided with synchronizer clutches and close coupled to the driven portion of a main clutch to minimize the momentum transfer through the synchronizers. A sectional housing for the transmission supports an eccentrically mounted hydraulic pump which can be rotated to a plurality of positions. An additional housing section can be added to hold a planetary gear system between the clutch and a power source to double the number of speeds while still minimizing the momentum transfer across the synchronizer clutches. The main shaft preferably is hollow to allow insertion of a PTO shaft connected directly to the power source.