Patent GB-190328010-A (GB)
Title: Improvements in and relating to Dirstributing Valves for Rotary and other steam Engines, Pumps and the like
Inventor: MARKS GEORGE CROYDON
Filed: 1903-12-21
Granted: 1904-03-10
Abstract: 28,010. Marks, G. C., [Knowles, J.]. Dec. 21. Roots' blower type; valves and valve gear.-Relates to rotary distributing and expansion valves for use in rotary and other steam engines, for hoisting, motor-car, marine, and other purposes, and for pumps, air-compressors, and the like. The valves are adapted for regulating and controlling engines in connection with a governor, and are described as applied to the rotary engine described in Specification No. 13,571, A.D. 1903. Valves are also provided for reversing the engines. The cutoff valve 13, Fig. 1, consists of a cylindrical tubular sleeve mounted within the distributing-valve 12 which revolves in the valve port 4, and about the cut-off valve. The cut-off valve is provided with ports 14, as shown in the modified arrangement in Fig. 5, arranged longitudinally to register with the ports 3 in the series of cylinders of the engine. A similar number of ports 15 of smaller area are provided in the distributing-valve 12, and are arranged in two spirals on opposite sides, the second port from the end being placed diametrically opposite the first, and the fourth opposite the third, and so on. They may, however, be arranged in one spiral line. In the modification, shown in Fig. 5, the valves are slightly tapered to provide adjustment for wear, a space a being left between the end of the cut-off valve and the stem of the distributing- valve. The ports 14 in this case are made slightly longer than those in the distributing-valve. The tubular valve spindle 16, which is screwed into the valve 12 and secured by a pin 17, passes out through a stuffing-box and is fitted with a wheel 19, Fig. 11, gearing with a similar wheel 20 on the piston shaft, as shown in Figs. 1 and 11, by means of which the valve is actuated. The spindle 21 of the cut-off valve passes through the hollow spindle 16, and is fitted with a crank-arm 22, Figs. 10 and 11, provided with a pointer 23 which moves over a dial to indicate the cut-off. The cut-off and port opening may be varied automatically under the varying loads upon the engine, by connection with an ordinary governor by means of a loose disc 24 mounted on the stem of the cutoff valve and provided with lugs 25 to engage the pointer. The disc 24 is provided with a pivoted lever connected at one end by a rod 27<a> to the disc, and at the other end to a rod of the governor. The steam inlet to the engine is in the head of the rear cylinder of the series ; the rear end of the valve projects into the inlet pipe. When applied to a reversing engine, the valve is located centrally at the top in a bush provided with ports opening to the main steam passages. The cut-off valve is provided with pairs of ports, side by side, separated by a longitudinal rib. The reversing-valves are operated to reverse the engine in the manner described in Specification No. 13,571, A,D. 1903. The cut-off valve may, however, be connected to an adjustable index mechanism, by means of which the power of the engine may be regulated as required for hoisting purposes, and for motor cars in climbing hills, and for other purposes.