Optical scanning device

Patent metadata

Field	Value
Publication number	US-12248142-B2
Application number	US-202017783892-A
Country	US
Kind code	B2
Filing date	Dec 11, 2020
Priority date	Dec 13, 2019
Publication date	Mar 11, 2025
Grant date	Mar 11, 2025

Abstract

This optical scanning device includes: a shaft part to which a mirror part is connected; a movable magnet; a base part; a ball bearing; a core unit that has a core body and a coil body and rotationally drives the movable magnet; and a magnet position holding member that is a magnetic body provided facing the movable magnet and magnetically attracts the movable magnet to a reference position. The core unit is disposed on the outer surface side of one wall section of a pair of wall sections of the base part. An angle sensor unit for detecting the rotation angle position of the shaft part is disposed between the core unit and the one wall section.

First claim

What is claimed is:

1. An optical scanning device, comprising:
a shaft part to which a mirror is connected;
a movable magnet fixed to the shaft part;
a base;
a bearing that attaches the shaft part to the base rotatably;
a core unit including a core and a coil, the core unit configured to drive the movable magnet rotationally; and
a position holding member that attracts the movable magnet to a reference position magnetically, the position holding member being a magnetic material that is provided in the core unit and faces the movable magnet,
wherein:
the base includes a pair of wall parts each provided with a notched hole through which the shaft part is inserted via the bearing,
the core unit is disposed on a side of an outer surface of one wall part of the pair of the wall parts, and
an angle sensor part configured to detect a rotation angle position of the shaft part is disposed between the core unit and the one wall part.

2. The optical scanning device according to claim 1 , wherein:
the angle sensor part includes an optical sensor, a code wheel, and a connector.

3. The optical scanning device according to claim 1 , wherein:
the angle sensor part includes a circuit board, an optical sensor and a connector both mounted on the circuit board, and a code wheel fixed to the movable magnet; and
the circuit board is disposed so as to be accommodated in a recess formed in the outer surface of the one wall part.

4. The optical scanning device according to claim 1 , wherein:
the angle sensor part is configured in such a way that light from the angle sensor part to an outside of the optical scanning device and/or light from the outside to the angle sensor part is blocked.

5. The optical scanning device according to claim 4 , wherein:
the light is blocked by a connector provided in the angle sensor part and/or a cable connected to the circuit board.

Assignees

• Takahashi Yuki
• Kagami Masaharu
• Kitamura Yasutaka
• Denso Corp
• Mitsumi Electric Co Ltd

Inventors

• Takahashi Yuki
• Kagami Masaharu
• Kitamura Yasutaka

Classifications

• H01F7/081

  Magnetic constructions · CPC title

• G01B11/26

  for measuring angles or tapers; for testing the alignment of axes · CPC title

• G02B26/105 Primary

  with one or more pivoting mirrors or galvano-mirrors (G02B26/101 takes precedence) · CPC title

• H01F7/122

  by permanent magnets {(H01F7/1615, H01F7/1646 take precedence)} · CPC title

• B81B5/00

  Devices comprising elements which are movable in relation to each other, e.g. comprising slidable or rotatable elements · CPC title