GB650042A - Improvements in or relating to flexible chamber pumps - Google Patents

Abstract

650,042. Flexible chamber pumps or compressors. HENRY, L. E. V. J. Aug. 28,1947, No. 23854. Convention date, March 7, 1941. [Classes 8(i) and 102(i)] [Also in Groups VI and XXXV] A pump comprises a resilient tubular member forming a pump chamber, connected between a fluid supply source and a point of use and squeezed against an abutment by a flattening presser to effect a pumping stroke, inlet and outlet control pressers located on opposite sides of the flattening presser and adapted to obturate the tubular member locally to control the fluid. flow, and means for imparting periodic movements to the three pressers in a pumping sequence. The pump described which is particularly adapted for blood transfusion purposes comprises a pair of rubber tubes 27 each of which are secured in supports 30, 30<SP>1</SP> mounted on a frame 1 by a hinged abutment plate 28. The tubes are each adapted to be squeezed sideways against the abutment plate by a plate 19 supported in adjustable posts 15<SP>1</SP>, 16<SP>1</SP> and reciprocated by cams 3, 4, through levers 7, 7<SP>1</SP> and 8, 8<SP>1</SP> respectively. Check valves 17, 18 which are actuated in timed sequence with the plate 19 by cams 5, 6 respectively through levers 9, 10 respectively, are adapted to obturate the tubes at spaced points adjacent each end of the plate 19 so that the action of the latter will cause fluid to be pumped through the tubes. The stroke of the plates 19 may be varied by moving the 'posts 15<SP>1</SP>, 16<SP>1</SP> relative to the levers 7<SP>1</SP>, 8<SP>1</SP> respectively by a lead screw 20 which has left and right hand threads engaging correspondingly threaded holes in the posts. Alternatively a rack and pinion device may be used. The posts carry slidable push rods 15, 16 which are in engagement with the plate 19 through dovetail connections. The tube supports 30, 30<SP>1</SP> may be adjusted relative to the plate 19 by a screw 39 so as to accommodate various sizes of tubes. The cams are mounted on sleeve members in engagement with a shaft 2 which is driven by a synchronous electric motor 62 through gears 68, 69, 70, 71 running in an oil bath 63. In the case of electrical failure the device may be operated by hand. An indicating device is fitted to show the instantaneous rate of pumping of the fluid whilst a separate counter device 47 is adapted to record the total quantity of fluid pumped in any predetermined time. The two tubes 27 may deliver to a common or to separate points of use and may be adapted to pump in simultaneous or alternate sequence a device being fitted to effect a quick change from one to the other. The tubes may have resilient bulb portions which are squeezed by the plates 19. The pump may be used for either liquids or gases.