Patent GB-490927-A (GB)
Title: Improvements in or connected with hydraulic gearing
IPC: F16H39/20
Filed: 1936-11-23
Abstract: 490,927. Hydraulic transmission of power; eccentrics; reciprocating pumps. WOOLER, J. Nov. 23, 1936, No. 32006. [Class 69 (ii)] [Also in Groups XXVI and XXVIII] A hydraulic variable-speed gear or infinitely variable torque converter comprises a body 1 rotatably mounted in a fixed casing 2 but normally restrained against rotation by a brake band 69; the body is provided with radially arranged pump cylinders 3, 4, 5 at the driving end and radially arranged motor cylinders 6, 7, 8 at the driven end thereof; [cylinders 5, 7, and 8 are not shown]. Each motor cylinder contains a piston connected to a cranked portion of the driven shaft. Each of the pump cylinders is provided with a piston 16, the rod 17 of which is connected to a ring 18 rotatably enclosing a block 14 restrained against axial movement by rings 15, and having a square-sectioned bore which receives a similarly sectioned angled portion 9a on the driving shaft 9 which is free to move axially, being keyed at 11 to the input shaft ; the shaft 9 is urged by a spring 20 to the position shown in which the block 14 is concentric with the cylinders ; the output of the pump is increased from zero by moving the shaft 9 axially against the thrust of the spring 20, this being effected by admitting liquid from an engine driven control pump through pipe 66, control valve 64, pipe 63, and passage 57 in the driven shaft 21, to act on the piston face 19 formed on the end of the shaft 9 ; adjustment having been effected, the valve 64 is moved to isolate the pipe 63 and to put the, control-pump delivery pipe 66 in communication with pipe 67 leading to the suction reservoir of the control-pump which reservoir may be constituted by the casing 2 ; to return the pump-operating mechanism to zero position, the valve 64 is moved to put the pipe 63 in communication with the pipe 67, the pipe 66 now being isolated. On each downward stroke of the piston 16, liquid is drawn from a low pressure reservoir 35 into the cylinder through non-return valve 38, duct 36 and port 37 ; on each upward stroke of the piston, liquid is delivered from the cylinder to a high pressure reservoir 41 through port 37 and non-return valve 42. Three distributing valves are provided, one for each of the motor cylinders ; each valve chamber is provided with three axially spaced sets of ports, viz. 30, communicating through chamber 40 and duct 39 with the low pressure reservoir 35, 28 communicating with the high pressure reservoir 41, and 29 communicating through recess 44 passage 45 and port 46 with the appropriate motor cylinder ; the piston valve 32 is acted on by spring 34 to hold its stem 31 against a plate 49 rotatably mounted on a swash plate 47 carried by and rotated with the driven shaft 21 ; the swash plate can be set to Forward or Reverse position by means of a sliding sleeve 50 connected to the swash plate by a link 51, and movable axially by member 52 formed with teeth engaged by a pinion 54 on a shaft 55 carrying an operating lever 56 operable by hand or foot. In operation, the swash plate is adjusted to forward or reverse position ; the valve 64 is then operated to admit control liquid to give stroke to the pump ; to obtain a " direct drive," the swash plate is set normally to the shaft 21 whereby the valves 32 are maintained in such a position as to trap the liquid in the motor cylinders ; the brake 69 is released, and all the parts rotate as one. The high pressure reservoir 41 is, provided with a pressurerelief valve, and a passage 68 serves for replenishment of the transmitter.