Patent · US Active

Rotation detecting apparatus and rotation detecting system

US8525464B2 · kind B2 · utility

7Cited by
6References
6Claims
0Family size

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Key dates

Filing dateFeb 24, 2011
Grant dateSep 3, 2013
Priority date
Expiry dateDec 8, 2031

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02P7/0094
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A rotation detecting apparatus for detecting a rotational state of a direct-current motor includes a driving device, a control device, an energization detecting device, an alternating-current component detecting device, and a rotational state detecting device. An impedance between brushes of the motor changes periodically in accordance with rotation of the motor. The alternating-current component detecting device detects change of an alternating-current component of electric current that is supplied to the motor based on an electrical quantity. The change of the alternating-current component is caused by change of the impedance caused in accordance with the rotation. The rotational state detecting device detects at least one of a rotation angle, a rotational direction, and a rotational speed of the motor based on a detection result of the alternating-current component detecting device.

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