The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 22, 1992
Filed:
Feb. 01, 1990
Applicant:
Inventors:
Paul Schmidt, Lennestadt, DE;
Alfons Hesse, Lennestadt, DE;
Gerhard Balve, Lennestadt-Oberelspe, DE;
Franz-Josef Puttmann, Lennestadt-Saalhausen, DE;
Assignee:
Dipl.-Ing. Paul Schmidt, Lennestadt, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
175296 ; 173 91 ;
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.