GB612715A - Improvements in or relating to speed change gear boxes for agricultural tractors and the like - Google Patents

Abstract

612,715. Change-speed gear. PATISSIER, A. Aug. 22, 1945, No. 21500. Convention date, May 6, 1941. [Class 80 (ii)] A change-speed gear, for agricultural tractors, comprises two sliding gear systems having a common axis, one being on the driving shaft 1 and the other on the aligned intermediate driven shaft 4, a freely rotatable gear 9 mounted between the two systems and engageable with either or both, and a lay-shaft 5 having a gear 8 constantly meshing with the rotatable gear 9 and gears engageable with the two sliding gear systems. A pair of sliding gears 2, 3 having dog teeth 17 is slidably splined on the driving shaft 1 for selectively meshing gears 6, 7 rigid with the lay-shaft 5 and for clutch engagement with dog teeth 15 on the gear 9 freely mounted on the aligned intermediate shaft 4. A sliding gear 10 splined to the intermediate shaft 4 has dog teeth 18 engageable with the teeth 16 on the freely-mounted gear 9 and may be moved longitudinally to mesh with the gear 11 on the lay-shaft 5 or the gear 14 of a countershaft reverse train 14, 12, 11. The final drive from the intermediate shaft 4 is taken through a reduction gear 26, 27, 29, 30 to a driving bevel gear 32 of a differential (not shown), gears 27, 29 being rotatably mounted on the shaft 5. The boss of the gear 27 extends outside the casing and is formed with claw clutch teeth 33, shaft 5 being likewise extended and having teeth 34. An annular member 35 with teeth 36 provides a drive for a power take-off 37 from either teeth 33 or 34. The gears 2, 3 and 10 are controlled by forks 21, 22 sliding on a rod 25 under the action of levers 23, 24 respectively. By this arrangement six forward and three reverse speeds are obtained.