GB569787A - Improvements in hydraulic shaft couplings - Google Patents

Abstract

569,787. Hydraulic couplings. FRASER, W. Nov. 7, 1943, Nos. 14606/43, 9529/44 and 11563/44. [Class 69 (ii)] A hydraulic coupling comprises an outer casing on a shaft 2, having a cam track to reciprocate pistons 16 in radial cylinders in an inner casing on a second shaft 1, the flow of liquid between the cylinders caused by relative rotation between the shafts being controlled by a valve 20 to vary the speed and torque transmission, a vent 53, Fig. 9, in. the valve or clearance round the valve, its spindle or an extension of its spindle providing a relief duct for escape of air and liquid from the pressure zone through which the liquid flows between the cylinders, into the outer casing which forms a low-pressure liquid reservoir. The pistons may carry pivoted slippers 6 engaging the cam track, or rollers which may be of larger diameter than the pistons. The valve 20 is spring- pressed and formed with passages 28 for flow of liquid from one side to the other, partly masked by a disc 29 spring-pressed up to a stop. The cylinder ports 19, controlled by the valve, may have tapering extensions 19b. Clearance may be provided between the valve spindle 22 and the bore of the end plate 13 of the inner casing, or between the spindle extension 22a and its sleeve 10b leading to apertures 22b in the wall 10. Replenishment valves 31, safety valves for the pressure zone, and air escape and inlet valves 40, 41 in the outer casing may be provided. Fig. 9 shows the valve formed with a passage 47 which may form the pressure zone. Impellers 49 may create or neutralize turbulence in the reservoir. The first Provisional Specification states that two rollers may be provided for each piston.