GB738498A - Improvements in or relating to torque converters - Google Patents

Abstract

738,498. Variable-speed gearing. BUTLER, J. R. Oct. 29, 1953 [Aug. 1, 1952]; No. 19579/52. Class 80 (2). An input shaft 11, Fig. 1, drives the carrier of a bevel differential gear, the side wheels 14, 15 of which are connected to the sun 18 and annulus 20 respectively of a spur epicyclic gear, the carrier 23 of which is connected to the output shaft 24, and a controllable hydraulic clutch 19, 25 is arranged between sun 18 and shaft 24 (as shown) or shaft 11, or between annulus 20 and shaft 11 or shaft 24. Additional epicyclic trains may be fitted, each having planets meshing between the annulus 20 and a sunwheel fixed to the preceding carrier. The clutch 19, 25 may be of piston-and-cylinder type, with a controlled delivery valve. Such control may be effected by a spring-loaded pedal so that the valve is fully open when the pedal is partly depressed, full depression also disengaging a main clutch between the power source and shaft 11. Alternatively, the control may be automatic by output load and speed. A rod 26, Fig. 2, operated by the load-responsive device controls a spring-loaded lever 28 controlling a spring-loaded arm 34 on the control valve spindle 35, the pivot 29 of lever 28 being on an arm 30 controlled by a cam arm 47 operated through a rod 45 by the speedresponsive device. The parts normally occupy the positions shown, with the arm 34 held against a stop 38 and the valve in a partiallyopen position such that the gearing gives maximum reduction. Increase in speed or reduction in load allows the valve progressively to close. A further rod 39 operated by the speed-responsive device acts through a lever 41 to hold arm 34 against stop 38 below a predetermined speed.