Document Type and Number:
Japanese Patent JPS5315001
Kind Code:
B1
Abstract:
The invention is for an impact tool comprising a pressure fluid operating piston and cylinder device in which pressure fluid, for the cyclic operation of said device, is controlled by control means responsive to changes in fluid pressure brought about by relative reciprocatory movement between the piston and cylinder. In one preferred embodiment of the invention said control means comprises a valve means for controlling the supply of pressure fluid to the cylinder, for the retraction of the piston, and for controlling the exhausting of said pressure fluid from the cylinder, for the advance of the piston, a chamber or chambers connected to the cylinder so that a fluid therein will be subjected to pressure changes by movement of the piston, and means responsive to pressures in said chamber or chambers and operative cyclicly to switch said valve means between a pressure fluid supply position and a pressure fluid exhaust position. Conveniently said chamber or chambers is or are connected to the cylinder so that the fluid in said chamber or chambers will be compressed by retraction of the piston. The pressure fluid, for the operation of the tool, may be a liquid and the fluid in the chamber or chambers, which is compressible, may be a gas. Alternatively the pressure fluid, for the operation of the tool, may be a compressible liquid and the fluid in the chamber or chambers a similar compressible liquid.
Application Number:
JP1143072A
Publication Date:
May 22, 1978
Filing Date:
February 02, 1972
Export Citation:
International Classes:
B25D9/12; B25D9/14; E21B1/26; E21C37/22; E21C37/24; (IPC1-7): B25D9/12