Patent GB-369935-A (GB)
Title: Improvements in and relating to hydraulic variable transmission mechanism
IPC: F16H43/00
Filed: 1930-12-23
Abstract: 369,935. Hydraulic transmission of power. BEDFORD, J., Lucerne, Old Bedford Road, and PARK, M. C., 54, Havelock Road, both in Luton. Dec. 23, 1930, No. 38669. [Class 69 (ii).] In hydraulic variable transmission mechanism, such as is described in Specification 352,034, of the kind comprising a reciprocating pump circulating liquid which acts on a system of vanes, a plurality of vane rings is provided, attached alternately to stationary and moving parts. In the form shown in Fig. 1, the pump pistons 16 are connected to bell-crank levers pivoted to the cylinder block, and operated from discs 4a, 4b, of variable eccentricity carried by the driving shaft 1. The pump cylinders are provided with non-return valves 18, 19, the delivery valves 19 leading to a chamber 20 having jets 21 adjacent to vane rings 23, 24, 25. The ring 23 is attached to a member 26, the ring 24 to the cylinder block, and the ring 25 to a sleeve 30 slidably keyed to the main casing 3. Dog clutches controlled by a sleeve 51 allow the cylinder block to be coupled to the driven shaft 2, at which time the rings 23, 25 are coupled to the casing 3 for effecting a forward drive ; for reverse drive, the cylinder block is coupled to the casing 1, and the ring 23 to the shaft 2, while the ring 25 is inoperative. In a modification, the member 26 carries both rings 23, 25. A slidable control sleeve 40 has pins 39 engaging cam slots 38 in levers 34 which control the eccentricity of the discs 4a, 4b; further motion of the sleeve 40, after the discs have been given maximum eccentricity, acts through a disc 42 to cause valves to close the jets 21. In another form, Fig. 5, a disc 4b is mounted between discs 4a, and their eccentricity is varied by the slidable members 74 engaging slots in the discs ; the members 74 are carried by collars 75, and are operated by a quadrant 90 meshing with teeth on a sleeve 81, having cam slots 80 engaging pins carried by a collar 75. A sleeve 82, connected to the sleeve 81, has cam slots 83 engaging pins 84 on a member, provided with inclined slots 88 for operating the jet-control valves. The vane rings 23, 25 are connected by a flange 68 and free wheel hub to an extension 73 of the casing 3, the ring 24 is attached to a shroud 67 carried by the cylinder block, and epicycle reversing gear is provided. In a further form, Fig. 9, the pump pistons have skirts slidable in guides 111, and their stroke is varied by rotating eccentrics 118 by screw and nut mechanism operated from a slidable 'member 126, the mechanism serving also to operate rotary valves 22, Fig. 10, controlling the jets 21. Vane rings 23, 25 are carried by a member 144, vane rings 24, 25a by a member 145 secured to the casing, and epicyclic reversing gear is provided. In a final form, Fig. 14, the pump is double-acting, non - return valves being provided for controlling the passage of liquid to and from the outer ends of the cylinders, and the annular spaces 111. Vane rings 23, 25 are carried by a member 67 having a free-wheel connection with the casing 3, and a vane ring 24 by the cylinder block. The pump eccentrics are adjusted by inclined surfaces 186 operated from a slidable ring 182, and the rotary control valve 22 is operated from a slidable ring 168. The rings 182, 168 are actuated in succession by levers 193,194 having pins engaging cam shaft 191, 192 in a plate carried by a control shaft 189.