GB910533A - Improvements in and relating to displacement-type rotary pumps - Google Patents

Abstract

910,533. Rotary pumps. SCHINDLER, W. Dec. 24, 1959 [Jan. 27, 1959], No. 43916/59. Class 110 (2). A displacement-type rotary pump, particularly a gear pump or an intermeshing screw pump, not described, comprises a casing 2, secured to a support 4 on which drive means for the pump is mounted, and having pipe connections 21, 22, 23, the casing being designed to receive, in independently insertable and removable manner, a pressure-regulating valve 12, a filter 16 and a complete pump unit 6 which when inserted engages its milled shaft end 28 with the drive means on the support 4. The valve 12 is placed in a bore 11 in which it is urged upwardly by a leaf spring 13 against a cover 17 secured by studs 18 and nuts. The filter 16 is received in a bore 15 and also is retained by the cover 17. The pump unit 6 comprises a cylindrical member 24 insertable into the bore 5 of the casing 2 and providing a bearing for the shaft 27 on which an internallytoothed rotor 26 is mounted. A cap 31 encloses a stuffing box 30 and fluid accumulating therein is returned, by a bore 32, to the pump chamber which is defined between a bore 33 in the member 24 and a sleeve 34 inserted in the bore 33 and secured by studs and nuts to the member 24. The sleeve 34 has a bore 35, eccentric to the bore 33, which receives an axle 36 for the pinion 37 meshed with the rotor 26. A sickle member 38 between the gears 26, 37, is integral with the sleeve 34, and when the pump is to be driven in reverse direction, the sleeve 34 is displaced by 180 degrees in the bore 33. The inlet pipe 21 leads, through the filter 16 and bore 59, to the suction chamber 60<SP>1</SP>, the surge chamber 61 discharging through the bore 63 to a bore 11<SP>1</SP>1 accommodating a rapid shutter 14 having a piston 48 on a pin 49 one end 70 of which engages a port 66 in the piston 52 of the valve 12, and the other end of which controls a passage 64 leading to the discharge pipe 22. The fluid delivery pressure is controlled by a screw 55 which adjusts a loading spring 53. If the pump pressure is adequate, the piston 52 and piston 48 rise and the fluid passes through ports 69 to the pipe 22. If the pump pressure falls, the piston 52, 48 fall and the passage 64 is closed. The fluid then passes up the bore 66 to the space 67 and through passages 71, 72 to the pipe 23 which returns it to the tank. The rapid shutter is removable by a tool insertable in the bore 11 and engaging the hexagon body 46. The casing 2 may receive a number of pump units 6. A handle 40 is temporarily screwed into the bore 35 to assist in handling the nut 6 when withdrawing or inserting it.