GB741922A - Improvements relating to regulating systems - Google Patents

Abstract

741,922. Cooling cylinders. VOITH GES., J. M. June 11, 1951 [June 12, 1950], No. 13838/51. Class 7(2) [Also in Groups XIII and XXIX] A fan 4 driven through a hydraulic coupling 3 by an engine 1 regulates the temperature of engine coolant circulating through radiator 5 and the engine by way of conduits. 6,.7, movement of a valve 21 controlling coupling filling being effected by a temperature responsive element 8 in the engine coolant circuit. The coupling is of the fixed scoop type in which output speed is proportional to the pressure in the scoop chamber. On a rise in engine coolant temperature, element 8 actuates a valve 26 which in turn actuates the piston valve 21, which movement partially blocks return pipe 17a leading back to the fluid reservoir 16 and hence raises the pressure in the scoop chamber of coupling 3. This pressure is communicated by way of ducts 25, 25a to a piston 23 on a follow-up slide valve 22 which is thereby caused to move against the pressure of a compression spring 24 and in the same direction as the movement of piston valve 21 thus restoring the relative positions of the valve 21 and slide 22 and interrupting the supply of fluid to the coupling 3 to avoid over-regulation and hunting. When the coolant tempertaure falls the element 8 operates the piston valve 21 to reduce the pressure in the scoop chamber of the coupling which movement is followed up as before by a corresponding movement of the slide 22. Specification 477,831 [Group XXIX], U.S.A. Specification 2,299,049 and German Specification 759,694 are referred to.