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:
May. 29, 1990
Filed:
Sep. 22, 1988
Arndt Bergner, Munich, DE;
Hilti Aktiengesellschaft, Furstentum, LI;
Abstract
An expansion dowel assembly is made up of an anchor bolt and an expansion sleeve laterally enclosing the bolt. The sleeve is expanded by driving it in the axial direction relative to the bolt so that the leading end of the sleeve widens as it moves axially over a conically shaped expanding member at the leading end of the bolt. Cutting teeth are formed on the outer surface of the sleeve at its leading end and provide a saw-tooth section. The teeth cut into the surface of a borehole in a receiving material and form an undercut in the borehole surface as the sleeve is expanded. To facilitate expansion, an annular groove is located in the inside surface of and adjoining the cutting teeth. The annular groove is spaced on the opposite side of the cutting teeth from the leading end of the expansion sleeve.