Improvements in valves and valve gear for rock drills and like percussive tools

摘要

138,032. Rayner, G. H. T., and Rayner, P. July 28, 1919. Fluid-actuated gears.-The valve is provided with a central enlarged head a and two perforated heads b, b1 on either side which control the cylinder exhaust through ports m, m1, m2. It is moved by compression and by pressure-fluid from the cylinder passing through one or the other of piston-controlled passages j, i and the corresponding perforated head b1, or b to act on one of the faces of the head a. The admission to the cylinder ends is controlled by piston extensions c, c' which engage ported blocks e, l. In the construction shown, during the motion of the valve fluid passes from one face of the head a to the other since it is narrower than the port m1. In a modification, four exhaust passages are provided, and the head a is wider than either of them. One of the passages b3 in each of the heads b, b1 is provided with a transverse outlet b4 to dispose of leakage along the pistons c, c'.