GB191503556A - Improvements in Piston Valves for Steam Engines. - Google Patents

Abstract

3556. Tinson, W. H. March 5. Piston packing.-Each head of a piston valve for a steam-engine comprises two plates 1, 2 secured on the valve rod 3, an outer spring split packing- ring 8 of iron &c., an inner ring 9 the outer periphery of which presses against the inside of the ring 8, the splits of the rings being arranged out of registration and preferably diametrically opposite. The split of the outer ring has transverse portions joined by one or more steam-tight portions parallel to the edges of the ring. The inner surface of each ring is eccentric to the outer surface, the thickest portion being opposite the split, and the rings are of such thickness that, when placed together with their splits diametrically opposite, the inner surface of the inner ring is concentric with the outer surface of the outer ring. Lubricating grooves 21 are provided on the outer surface of the outer ring, and means are provided to prevent the grooves from communicating with the split in the ring. Radial holes 22 extend from the grooves 21 to the interior of the inner ring to allow steam to pass to the interior when the valve head passes over the steam port. A pin 17, the head of which engages a recess in the ring 8, passes through the ring 9 and engages a recess &c. in the plate 1 to prevent the rings from turning in the valve head or relatively to each other.