Subsoil penetrating apparatus
US4596292A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 18, 1985 |
| Grant date | Jun 24, 1986 |
| Priority date | — |
| Expiry date | Apr 18, 2005 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B4/145
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A hydraulically operated self-propelled subsoil penetrating tool of the type including an elongated housing member having a penetrating nose with a forward anvil surface, the forward anvil surface defining one end of a cylindrical cavity, a rear anvil surface defines the other end of said cavity, a hammer is slideably mounted in the cavity and has impacting surfaces at either end thereof adapted to impact on the anvil surfaces, the direction of travel of the tool is being determined by the anvil upon which said hammer impacts, the hammer is slideably in said cylindrical cavity to selectively impact upon one of said anvil surfaces and has internal bores of different diameters defining forward and reverse piston surfaces, the forward piston surface area being greater than the reverse piston surface area, a valving member is slideable in one of the hammer bores between the forward and reverse piston surfaces and defines forward and rear variable volume fluid chambers. A means is provided for supplying hydraulic fluid under pressure to the rear chamber and the valving member is movable to alternately provide communication between the chambers whereby pressure of the forward piston surf…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.