GB190912893A - Improvements in Hammer Drills. - Google Patents

Abstract

12,893. Lake, W. E., [Ingersoll-Rand Co.]. June 1. Percussive drills.-In hammer drills &c. with fluid-pressure feeds, the controlling-valve 8 is arranged so that in one position it closes direct communication from the supply 16 to the tool 1 and opens communication from the supply to the tool through the feeding-means 23. The valve is held in one of four positions by a spring-pressed pin 15 engaging recesses in the handle 10. In the first position, Figs. 1, 2, 3, and 4, the valve closes supply to the feedcylinder 23 and the tool 1, opens the feedcylinder to exhaust through ports 22, 24, and opens the tool to exhaust through ports 20, 21, 19. When moving to the second position, Figs. 6, 7, and 8, supply is gradually opened to the feed-cylinder through a port 29 and graduated ports 26, and from the feed-cylinder through ports 30, 32, 27 to the tool, direct supply to the tool and exhaust being closed. In the third position, Figs. 10, 11, and 12, the supply to the tool and the exhaust are closed, and supply to the feed-cylinder is opened through a port 31, a cut-away part of the valve, and the port 30. In the fourth position, Figs. 14, 15, and 16, exhaust is closed, and direct supply is opened to the feed-cylinder and tool through the ports 31, 30 and 29, 27 respectively. Either the feedcylinder or the feed-piston may be secured to the head block 2, the other member being movable and forming the rear support.