GB542416A - Improvements in multiple rope variable speed pulley transmission gear - Google Patents

Abstract

542,416. Variable-speed gearing. MASON, F. R. EMBLETON, R., and METROPOLITANVICKERS ELECTRICAL CO., Ltd. July 5, 1940, No. 11311. [Class 80 (ii)] In a multiple rope or belt variable-speed gear an expanding pulley comprises coned discs 13 splined to a shaft 1 which is driven by gears 3, 4 from a power shaft 5. Alternate discs 13 are secured to rods 16 fixed to a sleeve 21 slidable on the shaft 1 and the intermediate discs 13 are fixed to rods 17 secured to a sleeve 22 slidable on the sleeve 21. The sleeves 21, 22 are carried by thrust bearings 26, 26a in housings 28, 28a screwed to a bracket 33. The latter and a bracket 12 at the other end of the pulley are connected together by a frame 45 and the whole can pivot about the axis of the driving shaft 5. Housings 28, 28a have gear wheels 31, 31a engaging pinion 36 on a spindle having a gear wheel 37. The latter can be rotated by a motor on a shaft 43 by a worm 42, wheel 41 and pinion 38. Rotation of the wheel 37 causes the housings 28, 28a to move in opposite directions and vary the pitch circle diameter of the expanding pulley. Slight turning of the brackets 12, 33, due to the driving torque adjusts the slackness of the belts. Relative movement of the housings 28, 28a may be obtained by cam means instead of the arrangement shown. In a modification, the adjustable pulley is mounted in a fixed pedestal 46, Fig. 6, and gears with a non- adjustable pulley 8 carried in a rocking frame 12a journalled on the driven shaft 5, the pulley 8 having pinions 3a engaging gear wheels 4a on the shaft 5. By this means the slackness is accommodated.