Patent GB-176023-A (GB)
Title: Improvements in or relating to internal combustion engines
IPC: F01L7/06
Filed: 1920-09-03
Abstract: 176,023. Nelson, O. T. Sept. 3, 1920. Valves; valve-gean.-In an engine having a rotary disc valve 27, Fig. 3, with a single port controlling inlet and exhaust ports in the cylinder head, one or more auxiliary valves 10 controlled by the pressure in the cylinder are arranged between the cylinder and the inlet port controlled by the rotary valve, so that the time of closing the inlet port is determined by the auxiliary valve instead of by the disc valve. The disc valve is provided with devices for packing, preventing tilting, and cooling, and the auxiliary valve is free to turn upon its seat for equalizing wear and may be controlled in part by the pressure in another working cylinder. As shown in Figs. 1 and 3, a sealing-ring 20 for the inlet port 6 in the cylinder head is pressed against the disc valve by springs 22, and is itself provided with packing-rings. A similar sealing-ring is arranged in the exhaust port. A sealing-ring 41 for the inlet passage to the valve chest rests on the upper surface of the valve, and a sealing-ring for the exhaust passage is carried by an arc-shaped plate 42 which is pressed against the valve by springs 44 supported from brackets 45. To prevent tilting of the valve when subjected to unbalanced pressure through the exhaust port in the cylinder head, a raised track 36, Fig. 3, extending along a portion of the periphery of the valve, is engaged by a. roller 46, Fig. 1, mounted in the cover of the valve-chest. For cooling, ducts 34 in the body of the valve connect annular chambers 32<1>, 30 in the valve chest, which are open to the atmosphere at 49, 50, Fig. 1, and a vane 35 on the periphery of the valve causes a circulation of cooling-air through the passages 34 radially inwards. The automatic auxiliary valve 10 is secured to a stem 12 and is cushioned by springs in both directions, so as to open and close rapidly at the beginning and end of the suction stroke. In the modification shown in Fig. 9, the rotary disc valve 21<x> is formed with a recessed annular flange 23x, and a recessed packing-ring 27x is arranged in the valve casing. Oil under pressure is delivered to the annular channels 24<x> in the valve seating adjacent to the recesses in the valve and in the packing-ring, for sealing the valve. The valve controls one exhaust port in the cylinder head, and two inlet ports 28<x>, 29<x>, one serving for each direction of rotation of the engine. There are separate inlet passages and manifolds 33<x>, 34<x>, for each direction of running, and also separate carburetter connections 50<x>, 40<x> and compressed-air connections 52<x>, 45<x>. Between the two inlet ports 28<x>, 29<x> and the cylinder is a single auxiliary valve 9<x> controlled by the pressure in the cylinder acting on the valve head and also on a piston 16<x> on the valve stem. The chamber 19<x> above this piston is connected to a similar chamber 9 of another cylinder chosen so that there is pressure in the chamber 19<x> at the time that the valve 9<x> is to be opened. The valves 21<x> of all the cylinders are connected by a coupling-rod which is driven by one or other of two dogs according to the direction of rotation, so that the valves automatically take up the correct setting. In a modification of Fig. 9, two auxiliary valves such as 9<x> are provided, one opposite each inlet port, and the space 19<x> is connected to an air cushioning-chamber.