Patent GB-862947-A (GB)
Title: Hydraulic variable speed transmission
IPC: F16H39/06
Filed: 1959-06-18
Abstract: 862,947. Hydraulic transmission of power. POWELL, P. B. June 18, 1959 [July 3, 1958], No. 20941/59. Class 69 (2). An hydraulic variable - speed transmission comprises inner and outer rotors 25, 39, Figs. 1 and 2, which are respectively secured to driving and driven shafts 15, 30 and define an annular working chamber, and inner and outer vanes 59, 66 movably supported by the rotors extending into the chamber. An apertured control means 48, 55 is positioned in the chamber and constrained against rotation, the portion 55 being laterally movable to vary the stroke of the inner vanes 59 and an outer cam 68 engages the radially-outer portions of the outer vanes 66 so that they are at all times maintained in engagement with the outer surface of the control means. The mixer rotor consists of two portions 25, 26 riveted together and secured by a pin 29 to the driving-shaft 15 supported by bearings 16, 17 in a housing part 11. The outer rotor consists of a part 40 secured to a flange 39 of a member 37 integral with the driven shaft 30 rotatably supported by bearings 31, 34 in a second housing part 12. Each rotor is provided with a plurality of radially-extending slots slidably receiving the vanes 59, 66. The outer vanes 66 bear at their inner ends against the control means in the form of a ring 48 which is secured to a plate 45 rigidly secured to the housing parts and has a circular outer surface eccentrically disposed relative to the inner and outer rotors and concentric with the outer cam 68, the radial distance between the outer surface and cam thus being at all points equal to the radial length of the outer vanes. The inner surface of the ring 48 is elongated in the horizontal direction to permit the portion 55 of the control means to be laterally moved by cams 75 which are disposed on rods having lugs 78 engaging notches in a bar 80 longitudinally movable by a screw 81 axially located in the housing part 11. Both the ring 48 and portion 55 are provided with diametrically-opposed apertures 50, Fig. 3. In operation, with the portion 55 in its extreme lefthand position, as shown in Fig. 2, clockwise rotation of the inner rotor pumps liquid upwardly through the apertures 50 to the outer rotor which thus also rotates clockwise at the same speed as the inner rotor, the liquid from the outer rotor passing downwardly so as to be returned through the lower apertures to the inner rotor. Longitudinal adjustment of the bar 80 moves the portion 55 to the right to reduce the output from the inner rotor until, when the portion 55 is concentric with the inner rotor and all the inner vanes extend the same amount, equal amounts of liquid are pumped through the upper and lower apertures and the outer rotor remains stationary. Further movement of the portion 55 to the right causes reverse rotation of the outer rotor. The inner vanes are maintained in contact with the portion 55 during the latter's movement by a ring 60 disposed between the portions 25, 26 of the inner rotor. A mechanism for cooling and/or removing air from the liquid may be connected to openings 95, 96 in the housing. Liquid leaking past the outer vanes may pass into a chamber 91 connected by one-way valves 92 with the working chamber. In an alternative embodiment, thecontrol means consists of an apertured ring 100, Fig. 4, having a circular outer surface and an eccentrically-disposed inner circular surface. The ring, together with bearings 107 supporting the outer cam 106 engaging the outer ends of the vanes 66<SP>1</SP> in the outer rotor, is secured to a plate 45<SP>1</SP> which is laterally movable relative to the rotors by a screw 81<SP>1</SP> to vary the speed and direction of rotation of the outer rotor.