Patent GB-1061911-A (GB)
Title: Improvements in or relating to hydraulic reciprocating pumps or motors
Inventor: JR ELIAS ORSHANSKY
IPC: F01B1/06
Filed: 1964-03-26
Abstract: 1,061,911. Hydraulic transmissions. E. ORSHANSKY and R. E. HATCH. March 26 1964, No. 12824/64. Headings F2C and F2D. [Also in Division F1] In a radial cylinder hydraulic pump or motor a piston reaction link 78 bears upon each piston 44 and a cam reaction link 90 is transposed between each link 78 and a cam ring 30. The cam links 90 are mounted in a ring 88 and pivot on bearings 92, the ring 88 being rotatable relative to a fixed hub 12 within which are the working chambers 46. The embodiment shown is a motor mounted in a road wheel of a vehicle and as shown in Fig. 3, bearings 82, 98 are in alignment with the pistons 44 so that maximum piston stroke is required for a full stroke of the bearing 98 on the cam track 31. Rotation of the ring 88 moves the bearings 98 out of alignment with the bearings 82 and the pistons 44, thereby reducing the piston stroke required for a full stroke of the bearing 98 on the cam track 31. In the motor shown there are two rows of cylinders and the links 78 are bifurcated, there being an anti-friction bearing (84) (Fig. 2, not shown) on either side of the bearing 86, which bearings are acted upon by the pistons 44. The links 90 are preloaded by secondary links 93 which have the same pivot points as the links 90, but which engage a cam track 33, and are in contact with the links 90 by leaf springs 102. Pressure liquid admittance and exhaust is controlled by spool valves 47 actuated by a cam ring (65) (Fig. 2). The angular setting of the ring 88 is controlled by a valve member 130 which is acted upon by hydraulic pressure in a chamber 40. Movement of the spool valve having lands 146, 148 in a sleeve 132 admits hydraulic fluid to either of cylinders 122 or 124 via openings 134 or 138 respectively. Movement of the arm 116 is transmitted to a further arm (112) (Fig. 5, not shown) directly connected to the ring 88 and the arm 116 also moves the sleeve 132 to close the openings 134, 138. The arm 116 is mounted on a shaft 114 and a shaft 165 engages the former shaft through a bevel gear 167 and a cylindrical rack 163. Movement of the arm 116 adjusts the timing of the cam ring for the valves 47 via the rack 163 so that the valve timing for the chambers 46 corresponds with the setting of the ring 88. A road vehicle may have a motor in each wheel (Fig. 9) pairs of motors being supplied by an engine-driven pump 176 through lines 188 or 190 and 180 or 182 respectively, depending on direction of rotation, thereby allowing the pairs. of motors to be controlled independently. A low-pressure pump 192 boosts the pressure in the low-pressure line 180 or 182, the pump drawing leakage liquid from a reservoir 196 and passing it through a heat exchanger 204 to cool the hydraulic system. Bypass valves 210, 212, 214 regulate the pressure therein. The pressure in line 207 is regulated by the vehicle speed through a sensor 218 and variation thereof controls the displacement of the motors by the pressure acting on piston 40 (Fig. 4) via line 39 which is connected to the low-pressure line 180 or 182. A pedal 226 controls the engine 178 and provides an input demand into a control 228. The input demand is integrated with the resistance of the motors and the resultant signal is supplied to the pump 176 via line 234 thereby regulating one of the pump cylinder blocks, and a similar control regulates a second pump cylinder block. A valve 238 throttles the line 180 for braking and a valve 238 between the lines 182, 188 allows for a slight differential flow to the motors when turning.