GB137945A - Improvements in and relating to tractors - Google Patents

Abstract

137,945. Kroyer, J. M. March 3, 1919. Compulsory differential driving; steering by differential braking. - Relates to fourwheeled tractors of the type having non-deflectable wheels, and more particularly to tractors of the kind described in Specification 132,103, in which the pairs of wheels on each side are geared together and one wheel of each pair is disconnectibly geared to the engine. The engine 8 is connected through the usual clutch 9 and gear-box 12 to a propeller shaft 13 carrying a pair of clutches 14, 15 connected respectively by gearing 16, 19 to countershafts 17, 20, which drive the rear wheels 5 through the usual pinions and' internal gears. Each lateral pair of road wheels is connected by chains 6 engaging sprocket-wheels on the road-wheel hubs. The clutches 14, 15 are operated by a shaft 23, Fig. 5, rotated by the hand steering-wheel and carrying a double-grooved cam 22 engaging a stud 25 on a pivoted fork 26, which in turn engages the internal members of the clutch so that either clutch can be disengaged at will. When one clutch is disengaged, the whools on that side cease to rotate, and the continued rotation of the other pair of wheels causes the tractor to turn to the right or left on an arc of small radius. A further movement of the hand steering-wheel operates the appropriate brakeband 29 on one of the clutches and holds the wheels on that side against rotation, when more abrupt turning is required. By allowing one clutch to slip, less abrupt steering is obtained.