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:
Jan. 17, 1989
Filed:
Oct. 05, 1987
Applicant:
Inventors:
Hans-Jurgen Hoereth, Langenbach, DE;
Anton Neumaier, Furstenfeldbruck, DE;
Assignee:
Hilti Aktiengesellschaft, , US;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B25D / ;
U.S. Cl.
CPC ...
173 14 ; 173116 ;
Abstract
In a hammer drill, a striking mechanism supplied percussive force to a tool. The striking mechanism includes a free piston slidably displaceable in a reciprocating manner within a guide cylinder. Balls mounted in the guide cylinder are spring biased into a recess in the free piston for securing the piston in a locked position so that it cannot deliver percussive force to the tool. The balls are spring biased by a ring encircling the cylinder with a spring pressing the ring in the axial direction of the cylinder against the balls.