Patent · US Expired

Rotary electrical hand-tool device and startup safety routine

US6697570B2 · kind B2 · utility

2Cited by

2References

8Claims

0Family size

Assignee

Hilti Aktiengesellschaft · LI

Inventors

Peter Hellmann · Obermeitingen, DE
Guido Werdun · Lüdenscheid, DE
Michael Reiner · Fellbach, DE

Key dates

Filing date	Jan 23, 2002
Grant date	Feb 24, 2004
Priority date	—
Expiry date	Jan 23, 2022

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10S388/935
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

An electrical hand-tool device and start-up safety routine protecting against start-up blockages, in which an electrical motor is connected, for a short time span (T0), with the current supply at a determinable resistance. At least one of a limit value (&agr;G) and a shut-off point in time (tA) is determined, for the safety routine in the event of tool blockage, using a measurement of the angle of rotation (&phgr;) of the rotor taken over the time span (T0) dependent on the start-up behavior of a rotor in the time span (T0).

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