Improvements in or relating to automatic control mechanism for starting and stopping centrifugal, rotary and reciprocating pumps

摘要

260,069. Pulsometer Engineering Co., Ltd., and Bj÷rnstad, J. Aug. 14, 1925. Controlling. - In control mechanism for automatically bringing into action or cutting out successively separate motor-driven pumps in accordance with the demand for liquid, means are provided to compensate for any variation in the pressure of the liquid supplied to a suction pipe common to the several pumps. In accordance with the demand the motors are successively energized through switches 6 - - 8 actuated by a tappet rod 18 connected to a float 25 in a stand pipe 25a communicating with a Venturi tube 27 or Pitot tube in the common suction pipe 4, and to compensate for variations in level in the supply tank 1 the switches 6 - - 8 are carried on a panel 5 connected with a float 17 therein. The panel carries a tappet for successively actuating switches 33 - - 36 which throw in liquid feed pumps, ring an alarm and when a critical tank level is reached cut out all the motors.