Patent · US Expired

Ram boring machine

US5148878A · kind A · utility

10Cited by

7References

10Claims

0Family size

Assignee

Dipl.-Ing. Paul Schmidt · DE

Inventors

Paul Wayne Schmidt · Lennestadt, DE
Alfons Hesse · Lennestadt, DE
Gerhard Balve · Lennestadt, DE
Franz-Josef Puttmann · Lennestadt, DE

Key dates

Filing date	Feb 1, 1990
Grant date	Sep 22, 1992
Priority date	—
Expiry date	Feb 1, 2010

Classification

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

Abstract

A ram boring machine having a striking piston that is axially displaceable in a housing, of which the forward and backward movement is controlled by a control sleeve connected to a supply hose and which engages in a cylinder chamber of the striking piston, and by one or more corresponding control openings in the striking piston, wherein the control sleeve is loaded both axially and torsionally, has axial and rotational stops and is rotatable and axially displaceable in a guide sleeve arranged at the rear end of the housing.

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