Title:
VARIABLE RELUCTANCE TYPE POSITION DETECTOR
Document Type and Number:
Japanese Patent JPH01202617
Kind Code:
A
Abstract:
PURPOSE:To lower a turbulence attributed to a change in permeance among those of an output electromotive voltage of a detector, by shifting a pitch of small gears of a rotor and a stator by 1/(N.M) or integral times. CONSTITUTION:Small gears 18 are formed in a rotor 12 at an equal pitch and four stator small gears 20 each are formed in large gears of a stator 10 at a pitch interval shorter by one-twenty fourth of the pitch of the small gears 18. With such an arrangement of the small gears 18 and 20, phases of changes in the permeance of an electromagnet 16 caused by the small gears 20 in the large gears are shifted by T/24 with one cycle of a fundamental electromotive voltage wave in winding phases U, V and W as T. When the number of large gears of a detector is N, thus permeance change is based on that with a cycle of T/N and a high-order permeance change is generated with a cycle of an integral fraction thereof. Here, the change in the fundamental permeance with a T/N cycle is especially large and thus, by offsetting the fundamental perme ance change, enabling the lowering of a turbulence of the output electromotive voltage waveform can be reduced.
Inventors:
IWAMATSU NOBORU
ENDO YUICHI
ENDO YUICHI
Application Number:
JP2652188A
Publication Date:
August 15, 1989
Filing Date:
February 09, 1988
Export Citation:
Assignee:
FANUC LTD
International Classes:
G01B7/00; G01D5/245; (IPC1-7): G01B7/00; G01D5/245
Attorney, Agent or Firm:
Aoki Akira (4 outside)
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