Patent · US Active

Handheld power tool and control method

US11123854B2 · kind B2 · utility

0Cited by

10References

14Claims

0Family size

Assignee

Hilti Aktiengesellschaft · LI

Inventors

Erwin Manschitz · Germering, DE
Walter Wissmach · Munich, DE

Key dates

Filing date	Jul 19, 2019
Grant date	Sep 21, 2021
Priority date	—
Expiry date	Dec 30, 2039

Classification

Technology area (CPC B)Performing Operations; Transporting
CPC primaryB25D2250/221
WIPO fieldMachine tools
WIPO sectorMechanical engineering

Abstract

A handheld power tool has a tool socket (2) to hold a tool (4) along a working axis (11), a motor (5) and a slip clutch (21) having a number of blocking elements. A sensor (27) serves to record a measured signal (28) as the measure of vibrations inside the handheld power tool (1). A band-pass filter (29) has a pass range in which a frequency lies that is equal to the product of the rotational speed of the wheel (22) on the drive side and the number N of blocking elements (24). The measured signal (28) filtered by the band-pass filter (29) is fed to an evaluation unit (30). When the filtered measured signal (28) exceeds a limit value, the evaluation unit (30) reduces the rotational speed of the motor (5).

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