Patent · US Expired

Rotation detecting device with magnet brake

US5543672A · kind A · utility

30Cited by
7References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 11, 1990
Grant dateAug 6, 1996
Priority date
Expiry dateOct 11, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01P1/04
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A rotation detecting device for vehicle speedometers includes a housing, a magnetic induction device, and a magnetized rotor near the magnetic induction device. The rotor is connected through a coupling to a rotation source. A braking device forms a magnetic circuit between one end surface of the rotor and the housing, and brings the rotor into pressure contact with the housing by a magnetic attraction force generated in the magnetic circuit. Accordingly, a stable and proper braking torque can be applied against rotor vibration, to prevent a false output signal while idling. Furthermore, the amount of wear of a bearing for rotatably supporting a rotating shaft of the rotor can be reduced to improve durability of the rotation detecting device by reducing the braking torque during high-speed rotation of the rotor.

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