Patent · US Expired

Pneumatically reversible ram drilling tool

US6371220B1 · kind B1 · utility

4Cited by

6References

7Claims

0Family size

Assignee

Tracto-Technik Paul Schmidt Spezialmaschinen · DE

Inventors

Alfons Hesse · Lennestadt, DE
Franz-Josef Puttmann · Lennestadt, DE

Key dates

Filing date	Dec 15, 1999
Grant date	Apr 16, 2002
Priority date	—
Expiry date	Dec 15, 2019

Classification

Technology area (CPC E)Fixed Constructions
CPC primaryE21B4/145
WIPO fieldCivil engineering
WIPO sectorOther fields

Abstract

In a ram drilling tool for producing bores in the ground and having a percussion piston which is moved to and fro in a casing, a control sleeve is guided such that it can be displaced on a control pipe projecting into a percussion-piston chamber and whose axial position determines the direction of movement of the tool. In order to permit the movement to be reversed, a control chamber connected to a control-air line is arranged between the control pipe and the control sleeve, and its front end terminates flush with a collar at the front end of the control pipe.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.