GB854168A - Multi-cylinder two-stroke internal combustion engines - Google Patents

Abstract

854,168. Charging two-stroke engines; regulating. SULZER FRERES S.A. April 12, 1957 [April 14, 1956], No. 12092/57. Classes 7(2) and 7(6). A multi-cylinder diesel engine has inlet ports 3, Fig. 1, supplied with scavenging and charging air by an exhaust gas turbo-supercharger 6, 7 via a common manifold 10 and individual cylinder inlet passages 11 into which pumping chambers 12 open laterally and which have nozzles or oneway valves 14 tending to prevent back flow and the action of which can be varied, e.g. so that at starting and low speeds the valves 14 are operative to render the chambers 12 effective to supplement the supercharger 7 and at high speeds the valves 14 are rendered inoperative so that pumping losses due to the chambers 12 are obviated. As shown each valve 14 is mounted on a lift valve 18 which can be operated by a handle 15, but automatic variation of the action of the nozzles or one-way valves may be effected cyclically or in accordance with engine speed, torque or fuel control setting, supercharger speed or delivery pressure, exhaust gas pressure or temperature or cooling-water temperature. In Fig. 2 (not shown) a nozzle is mounted on a flap valve operated under engine governor control; in Fig. 3 (not shown) two one-way valves in parallel are mounted on a butterfly valve linkage-operated by a piston acted on by pressure in the manifold 10; in Fig. 4 a one-way valve 14 is mounted on a slide valve 20 cyclically operated, subject to the overriding control of such a piston 25, by an engine-driven camshaft- 27 movable to vary the open period of the valve 20; in Fig. 5 (not shown) a nozzle by-pass passage is controlled by a butterfly valve operated by a piston as above; Fig. 6 shows a one-way valve 14 having a pneumatic dashpot 36 which partially or wholly prevents the valve from closing at high engine speeds. Reference is made to the use of an hydraulic dashpot, and of several by-pass valves operated in stages.