GB190104971A - Improvements in or connected with Means for Distributing and Controlling the Actuating Fluid in Engines or Motors. - Google Patents

Abstract

4971. Clarke, Chapman, & Co., and Woodeson, W. A. March 8. Rock drills, percussive. Relates to means for distributing and controlling the actuating fluid in rock drills and the like, actuated by steam or compressed air, of the kind described in Specification No. 16,317, A.D. 1899, [Abridgment Class Pumps &c.]. Fig. 1 shows a section through the cylinder and valve-chest of a directacting pump, in which the main valve 1 working in a ported liner 3 is actuated by a portion of the working fluid distributed by an auxiliary valve 2 working in an inner liner 4 and operated from the engine piston-rod. Fig. 3 shows a section of the valve-chest on the line A-A. Fig. 4 a section on the line B-B, and Fig. 5 shows a development of the liner 3. The live steam enters by the branch 19 and passes to the main valve by passages 15, 36, and the exhaust leaves by the branch 28, being conducted from the main valve by passages 32 so that the main inlet and exhaust passages are opened and closed by the auxiliary valve 2. One of the chief features of the invention is that provision is made for expansive working, the admission ports 37, 17 being located so that they are closed before the end of the stroke of the main piston 13. In order to enable steam to be admitted directly to either end of the cylinder if the piston stops before completing the stroke, the steam passages 15, 36 are externally connected to the steam-supply pipe by pipes 74, 75 controlled by suitable regulating valves. Small passages, formed by grooving the outside of the shell or liner 3, are also provided for holding the main valve 1, for cushioning the main piston 13, as well as for actuating the main valve. Recesses or grooves are also made where each port opens into the liner in order to balance the two valves laterally.