GB378754A - Improvements in or relating to superchargers for internal-combustion engines - Google Patents

Abstract

378,754. Hydraulic transmission of power. SINCLAIR, H., 6, The Crest, Surbiton Hill, Surrey. Dec. 23, 1931, No. 35611. Convention date, Jan. 10. [Class 69 (ii).] A blower for supplying air or mixture to the engine of aircraft is driven through a hydraulic coupling of the Fottinger type-such as described in Specification 378,726-wherein there is variable slip this being controlled automatically according to the working conditions of the engine. The impeller 13 is mounted on an extension 16 of the engine shaft and is driven through spur gear 17, 18, 22, 8 and the coupling 24 ; the core member 23 of the driven element of this coupling is formed with a collecting chamber 29 having exhaust passages 30 to allow flow of oil out of the coupling to a sump. The lubricating oil pump supplies oil through a bore 31 in the shaft on which the driving element of the coupling is mounted, passing into the coupling through ducts 32. The circulation of oil and thereby the amount of slip is controlled by adjusting the flow to the coupling ; the carburetter throttle 5 is interconnected with a valve 46 in the oil bore 31 so that at small throttle opening there is no oil flow and much slip in the coupling. A second valve 33 is connected to a bellows 36 loaded with an adjustable spring ; the bellows is contained in a chamber connected by a pipe 38 to the delivery side of the blower so that the flow of oil in the bore 31 depends on the pressure of the charge. In place of the valve 46 a valve may be placed in the pipe 38 and moved in correspondence with the throttle ; the blower works then only in sub-normal pressures. When used on compression ignition engines the valve 46 is interconnected with the fuel control. The control may be subject to the variations in temperature of the engine ; for this purpose the bellows contain a gas or volatile liquid and cooling water or lubricating oil is caused to flow through the annular chamber 50. In another arrangement the control may be directly due to barometric conditions. Three couplings may be arranged in parallel to drive the impeller, the flow of oil to the coupling chambers being controlled by one valve or set of valves. Couplings as described in Specifications 314,157 and 328,028, [both in Class 69 (ii), Hydraulic presses &c.], may be used. In place of the lubricating oil any other liquid circulating medium may be used.