Patent GB-644150-A (GB)
Title: Improvements in and relating to power transmissions
IPC: F15B13/06
Filed: 1948-01-05
Abstract: 644,150. Rotary pumps. VICKERS, Inc. Jan. 5, 1948, No. 266. Convention date, Jan. 4, 1947. [Class 110(ii)] [Also in Groups I and XXIX] A hydraulic power device for supplying one or more pressure lines comprises a liquid-supply tank 16 and a body member 10 supporting a sliding vane pump 14 and containing one or more distributing valves 12. The pump supplies a pressure chamber 48 which, in the neutral position of valve 12, as in Fig. 4, allows liquid to flow through passages 54, 136, 134, groove 332, passages 164, 190 back to the tank. When the valve 12 is shifted to the right, land 324 blocks passage 170 and causes pressure fluid to flow to one end of a doubleacting motor through pressure build-up in passage 136 which is connected to passage 176 by an annular groove 334. At the same time, groove 332 connects tank passage 164 to passage 174 to allow discharge of liquid from the other end of the motor cylinder to the tank. When the motor operation is complete the releasing of valve 12 will allow the valve to return to neutral position under force of the centring spring 288. An adjustable pressure-relief valve 128 is provided. By moving the valve to the left the tank-return passage 164 is blocked by land 326 and pressure-passage 136 is connected to the other end of the motor cylinder by way of groove 334, the second end of the cylinder being exhausted by means of groove 336, passage 166 and slot 192. The pump comprises a rotor 26, driven by a shaft 36, having outwardly-sliding vanes 28, and two diametrically-opposite pumping chambers 44 within an outer ring 30. The ends of the chambers 44 are sealed by a floating plate 34 under spring and liquid pressure. The various pump parts are positioned by dowels. The pump shaft 36 may be reversed in rotation, and the dowels and fixing screws being removed, the ring 30 may be removed and the pumping chambers 44 ,arranged on axis B-B instead of A-A (Fig. 2). The tank 16 is made of sheet metal, a beaded edge 98 holding a seal 100. A combined air vent and filler cap 24 is provided, allowing atmospheric pressure within the tank. The liquid returning to the tank 16 from a discharge passage 123 contacts a baffle 20 which slows it down, allowing air bubbles to separate out. Liquid passes to the pump through a filter 22 comprising a screen 102 mounted between end pieces 104, 106 which are pressed apart by a spring 112. The coils of the latter are large enough to support the screen. A cap 188, of the member 10, may be removed, and .one or more parallel distributing valves inserted (see Fig. 12). A double-acting valve 198 (Figs. 12 and 16) controls a doubleacting piston motor 236 which actuates an operating rod 322, and a single-acting valve 242 controls the motor piston 316 which actuates a rod 318. Caps 276, 278 seal the ends of the valve recesses, the end chambers 300, 302 communicating with the tank 16. To operate the motor 316 the valve 242 is shifted to the right and land 266 blocks the unloading passage 170. Liquid is led from pressure passage 136 to passage 176 by means of groove 260. When the piston 316 has been raised to the top of its stroke, excess pressure will be relieved to the tank 16 through relief valve 128. By releasing the operating handle, valve 242 will return to its central, neutral position by means of a centring spring 288, and unload the pump via passages 134, 170, groove 272, passage 164, slot 218, passage 204, groove 274, passage 206 and slot 190 leading to the tank. The valve 198 acts similarly to the valve 12 described above. When both valves are moved to the right, pressure fluid will be directed through passages 176, 224 to the respective motors. Discharge fluid from the other end of motor 236 is directed to the tank 16 via passage 222, groove 274, passage 206 and slot 190. To reverse the direction of travel of the motors 184, 236, valves 242, 198 must be shifted to the extreme left. The various ports and passages are preferably formed by drilling the member 10. Grooves are formed in the cap 188. The device may be used for actuating accessories on a farm tractor, the engine of which may be used to drive the shaft 36. Pressure fluid is used to drive the vanes 28, in slots 74, outwards. into contact with the ring 30, the supply being by way of annular grooves 76. 78. A drain 308 is provided for the tank. Specification 644,199 is referred to.