GB191010228A - Improvements in Distributing Devices for Compressed Air Tools, Rock Drills and the like. - Google Patents

Abstract

10,228. Armaturen-und Maschinenfabrik "Westfalia" Akt.-Ges. Aug. 23, 1909, [Convention date]. Fluid-actuated gears. - In compressed-air tools, rock drills, &c., having separate admission valves at the ends of the cylinder, which are operated by the compression caused by the working piston at the ends of its stroke, the fluid works expansively, and the valves, after the closure of the admission ports, are held in a closed position during the remainder of each stroke. In the arrangement shown in Fig. 1, auxiliary pistons b, d are arranged behind the lift valves a, c. The ends of the auxiliary cylinders are connected to the main cylinder by auxiliary ports in the manner shown. When the piston during its forward stroke passes the port i, the valve a is closed and held to its seat by the fluid pressure supplied to the upper surface of the piston b. When the piston passes the exhaust port m the valve is held to its seat by the fluid pressure from the other end of the main cylinder acting on its outer face. In the modification shown in Fig. 2, the valve is made in three parts o<1>, o<2>, o<3>. The annular areas of the part o<2> are greater than the areas of the parts o<1>, o<3>. The outer chamber p is connected to the other end of the cylinder, and the ends r, q of the intermediate chamber are connected to the atmosphere and the cylinder respectively in the manner indicated.