Patent · US Expired

Anti-theft apparatus including a screw with an anti-theft safety head

US4964773A · kind A · utility

12Cited by
8References
24Claims
0Family size

Inventor

Key dates

Filing dateSep 21, 1989
Grant dateOct 23, 1990
Priority date
Expiry dateSep 21, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T70/5867
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A screw with an anti-theft safety head is suggested, which safety head is provided with a bore receiving a substantially cylindrically constructed tool extension part originating at the screw. At least two rotatably supported pins are arranged substantially parallel next to the bore in the anti-theft safety head, which pins are each rotationally fixed to a locking member. The locking members can be swung into an annular groove on the tool extension part by rotating the associated pin from its upper end, which upper end is accessible from outside and is constructed as an adjusting tool adapter segment. Only when all pins and locking members assume a very precisely defined position, it is possible to pull off the anti-theft safety head. The solid construction of the anti-theft safety head provides a novel anti-theft protection of the screw.

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