| 摘要 |
780,637. Diaphragm pumps. SVENSKA AKTIEBOLAGET GASACCUMULATOR. Sept. 30, 1955 [Oct. 6, 1954], No. 27884/55. Class 102(1). A pump, e.g. for pumping blood, comprises a pair of flexible tubes 1, 2 fitted with valves 3 .. 6, and alternately compressed by a presser 10 reciprocated by a crank 9. The amount of liquid pumped is controlled by limiting the distortion of the side of the tubes 1 and 2, opposite to the side actuated by the presser, by flexible chambers 12, 13 containing fluid under a variable pressure. The chambers 12, 13 are supplied with pressure fluid through a pipe 20, valve device 19 and pipe 18. To control the pressure in the flexible chambers a manuallyadjustable by-pass valve 24 is provided, and in addition a throttle needle valve 27 is actuated by a lever 31 connected to a diaphragm 35 forming the base of the suction vessel 34; this arrangement prevents the level of the liquid in the vessel 34 from falling below a certain level. The throttle valve 27 may pass through its seat and further movement of the lever 31 actuates a piston valve 26 to open the pipe 18 to atmosphere. The output of the pump may be controlled by placing the chambers 12, 13 between the presser 10 and the tubes 1, 2. |
