GB882807A - Improvements in fluid couplings - Google Patents

Abstract

882,807. Hydraulic couplings. ROBSON, C. March 4, 1960 [March 13, 1959], No. 8863/59. Class 69 (2). A method of controlling a fluid coupling having an impeller 2 and runner 4 between a driving motor and a load comprises automatically varying the volume of fluid in the coupling in relation to the speed of rotation of the reservoir of the coupling whereby the power transmitting capacity of the coupling is analogous to the power producing capacity of the motor. The reservoir is divided into chambers 12, 13, 23 and 28, the chamber 23 communicating with the working circuit of the coupling by means of a peripheral gap 24, and with the chambers 12, 13 by a scoop tube 26 having nozzles 31, 32. Each chamber 12, 13 has a scoop tube 15, 16 which is carried by a yoke 17 mounted in bearings 18 and urged to a neutral position by a torque bar 19, and each scoop tube is connected by a flexible pipe 20 to a passage 30 leading to the chamber 28 from which fluid is passed to the chamber 23 by a scoop tube 25. During rotation the scoop tubes 15, 16 are moved radially by centrifugal force against the force of the torsion bar and the centrifugal force acting on counterweights 22, scoop tube 15 being arranged to move radially inwards, and scoop tube 16 radially outwards, with increases in the speed of rotation of the reservoir. In the lower speed ranges, both scoop tubes 15, 16 are in their radially-outermost position to empty the chambers 12, 13 and the coupling is filled. In the higher speed ranges, the centrifugal force moves the scoop tube 15 radially inward so that fluid accumulates in the chamber 12 and the slip of the coupling increases. When the engine is slowed by a load tending to stall the coupling, the scoop tube 16 moves radially inwards so that fluid accumulates in the chamber 13 to increase the slip of the coupling.