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:
Aug. 05, 1997
Filed:
Jan. 05, 1996
Rolf Bereiter, Grabs, CH;
Peter Goepfert, Bonstetten, CH;
Hilti Aktiengesellschaft, Schaan, LI;
Abstract
An explosive powder charge operated fastening element setting tool has a hydropneumatic damping unit (17) and includes a housing part (1) forming a piston guide (5, 6) for driving fastening elements and a handle part (15) displaceable against the force of the damping unit (17) in the setting direction relative to the housing part (1). The handle part (15) supports a cylinder (18) containing a liquid medium (21) under gas pressure. The housing part (1) cooperates with a piston (23) displaceable in the cylinder (18) against the flow resistance of the liquid medium (21). The damping unit (17) has no moving valve parts. At least one through aperture (24) is provided for the liquid medium (21) flow between a front and a rear cylinder space when the piston (23) is displaced. The aperture (24) has a least cross-section (M) so that the liquid medium flowing into the front cylinder space as a fastening element is driven has an effective flow cross-section corresponding to the least cross-section of the aperture (21), while after the fastening element has been driven the effective flow cross-section of the aperture from the front cylinder space into the rear cylinder space is smaller than the least cross-section of the aperture.