Patent · US Expired

Method of and apparatus for preventing accidents during working with hand-held tools with a rotatable working tool

US6111515A · kind A · utility

57Cited by
7References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 1, 1999
Grant dateAug 29, 2000
Priority date
Expiry dateDec 1, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T408/14
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A method of and an apparatus for preventing accidents caused by blockage of a rotatable tool when working with a hand-held tool including the rotatable tool (8), a drive motor (7) for driving the rotatable tool (8), and means (5, 6) for interrupting transmission of a drive torque from the drive motor (7) to the rotatable tool (8) dependent on an operational condition of the hand-held tool, with the method including determining the operational condition of the hand-held tool by measuring displacement of the hand-held tool in space in at least two points of the hand-held tool spatially spaced from each other and spaced from a tool axis; subtracting two obtained displacement measurement variable (a.sub.1, a.sub.2) from each other; and thereafter, calculating an actuation signal that actuates the interrupting means (5, 6); and with the apparatus including sensors and an evaluation circuit for implementing the method.

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