Title:
磁石組立体の製造方法、ならびにエンコーダおよびエンコーダ付きモータ
Document Type and Number:
Japanese Patent JP7270395
Kind Code:
B2
Abstract:
To suppress magnetic interference of a first magnet and a second magnet, and enhance angle detection accuracy by reducing a gap between a magnet and a magnetic sensitive element.SOLUTION: An encoder 10 comprises: a magnet assembly 15; a circuit board assembly 13 including a first magnetic sensitive element 171 and a second magnetic sensitive element 172; and an encoder holder 14. The magnet assembly 15 has a magnet holder 19 which integrally rotates with a rotation axis 2, and a first magnet 161 and a second magnet 162 which are fixed to the magnet holder 19. The first magnet 161 has an N pole and an S pole magnetized for each pole in a circumferential direction, and the second magnet 162 has a plurality of N poles and S poles alternately magnetized in the circumferential direction. The magnet holder 19 is made of a magnetic material including a shield section 193 positioned between the first magnet 161 and the second magnet 162 which are separated in a radial direction. A magnetized surface 161a of the first magnet 161 is located at a position depressed lower than a tip surface 193a of the shield section 193.SELECTED DRAWING: Figure 13
Inventors:
Yutaka Saito
Application Number:
JP2019011200A
Publication Date:
May 10, 2023
Filing Date:
January 25, 2019
Export Citation:
Assignee:
Nidek Instruments Co., Ltd.
International Classes:
G01D5/245; G01D5/244; H01F13/00
Domestic Patent References:
| JP2012112707A | ||||
| JP2015114209A | ||||
| JP8022914A | ||||
| JP2018042332A | ||||
| JP2019009885A | ||||
| JP2018132353A |
Foreign References:
| US20150108968 |
Attorney, Agent or Firm:
Kawai Toru
Shin Kodaira
Nobuko Kawaguchi
Shin Kodaira
Nobuko Kawaguchi