Month in the Patent Office

A split or undivided cast‐iron, etc., packing‐ring F for junk heads of sleeve‐valve engines is supported in a groove open towards the end of the head by a steel, etc., spring ring E engaging grooves in the ring and head. Removal of an undivided ring is effected by a sleeve G engaged over the ring and carrying screws G1 by means of which the inner ring can be compressed. When a split ring is used, the edges of the split are cut away to avoid fouling ports in the valve. Alternatively, the ring is locked with its split out of register with the ports, by a radial pin F3 secured by a rivet F4.