GB465693A - Improvements in or relating to steam engines - Google Patents

Abstract

465,693. Engine valves and valvegear. SOHOLT, J. A. June 9, 1936, No. 16121. Addition to 402,585. [Class 122 (ii)] In a double-acting, triple-expansion engine of the kind described in the parent Specification, the cylinders are provided with exhaust ports positioned in the cylinder walls between the middle and the two ends of each cylinder. Slide valves are arranged between the cylinders, and control the exhaust from the higher-pres. sure cylinders and the admission of the lowerpressure cylinders. The valves are arranged at each end of the cylinders which have two sets of exhaust ports placed preferably at a distance from the ends at positions of the pistons corresponding to a rotation of 60‹ of the cranks. The exhaust from the cylinders 4, 5 pass through ports 17, 17<1>, 22, 221 and passages 20, 201, 25, 25<1> to the ends of the cylinders 5, 6 respectively. The L.P. exhaust passes through ports 27, 271 to chests 28, 28<1> connected through pipes 29, 29<1> to a valve-controlled exhaust 30. The H.P. admission is controlled by valves as described in the parent Specification. The slide valve-gear is shown in Fig. 5. Eccentrics on a chain-driven shaft 34 operate links 39 connected by rods 41 to slides 42 carrying rollers which engage cam surfaces on rocking-levers 46 which actuate the valves 18, 18<1> against the resistance of springs 52, 53. The admission in the cylinders during forward motion lasts through 120‹, but in reverse, through 60‹.