GB544251A - Improvements in or relating to infinitely variable speed gears - Google Patents

Abstract

544,251. Variable-speed gearing. SCHMID, F. May 27, 1940, No. 9284. Convention date, May 27, 1839. [Class 80 (ii)] In an epicyclic gear a shaft 1a having a sun pinion 3 is driven at variable speed from a shaft 1 having a sun pinion 2 by varying the speed of the planet pinion carrier 7, 8 by throttle control of the delivery from axially arranged plunger pumps 31 the cylinder block 10 of which is fixed to a casing 9 secured to the carrier 7, 8. The pump pistons 31 are connected to a wobbler disc 26 having a gimbal connection with the casing 9 and mounted on bearings 25 so as to be rotatable about an axis inclined to the axis of the shaft 1. The casing 9 and the parts connected thereto are rotatably mounted by bearings 11, 12, 13 upon a fixed sleeve 14. The pump cylinders 32 are inter-connected by a duct 55 and, in the latter between each pair of cylinders is a throttle valve 56, Fig. 9. The latter is cylindrical and has a port 57 corresponding to the duct 55 and a coned sealing face 58 pressed into contact with a sealing face 60 by a spring 59. At its end the valve '56 has a bevel pinion 64 meshing a gear 65 linked to a sleeve 71 so that axial movement of the latter by means of a hand lever 74 produces rotation of all the valves 56. The block 10 has a pressure chamber 39 supplied by an auxiliary pump 43 actuated by a fixed eccentric 50. Ducts 40 from the chamber 39 lead to the cylinders 32 so as to register with a circumferential groove 33 and diametral duct 34 in the pistons 31 when the latter are at the end of their suction stroke. The ducts 34 are connected to the cylinders 32 through spring controlled valves 38. Leakage losses are thus made up by flow past the valves 38. A pressure control valve 53, Fig. 8, is fitted to the pressure chamber 39.