Drive mechanism for oscillating electric products of personal use, particularly dry shavers

US6441517B1 · kind B1 · utility

Assignee

• The Braun Corporation · DE

Inventors

• Thomas Brum · Oberursel, DE
• Alexander Klos · Hofheim, DE
• Holger Port · Schwalbach, DE
• Werner Port
• Uwe Schaaf · Zwingenberg, DE

Key dates

• Filing date: Jun 21, 2001
• Grant date: Aug 27, 2002
• Expiry date: Jun 27, 2021

Classification

• Technology area (CPC H): Electricity
• CPC primary: H02K33/16
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

The invention is directed to a drive mechanism for driving a working unit, movable in a rotary oscillating manner, of domestic appliances, particularly dry shavers. The drive mechanism of the invention includes a permanent magnet motor which has a stator with an exciter winding and a rotor with at least one permanent magnet positioned in the stator field and rotatably mounted on a shaft, a reset device for returning the rotor to a position of rest in such a way as to enable the rotor to oscillate about the position of rest, a coupling device for coupling the rotor to the working unit, wherein the coupling device is connected to the rotor in spaced relationship to the rotor shaft, a detecting device for detecting the oscillatory motion of the rotor, and an actuating unit for actuating the permanent magnet motor in response to the detected oscillatory motion, provision being made for frequency control elements for actuating the permanent magnet motor with a frequency corresponding approximately to the resonant frequency of the rotor.