Vibration actuator and electronic apparatus

Patent metadata

Field	Value
Publication number	US-12046975-B2
Application number	US-201917259206-A
Country	US
Kind code	B2
Filing date	Jul 9, 2019
Priority date	Jul 11, 2018
Publication date	Jul 23, 2024
Grant date	Jul 23, 2024

Abstract

This vibration actuator has a movable body having a coil, a fixed body having magnets, and a shaft part that rotatably supports the movable body, wherein the movable body reciprocally and rotationally vibrates around the shaft part with respect to the fixed body through the interaction of the coil and the magnets. The magnets are arranged in a direction perpendicular to the axial direction of the shaft part and each have two magnetic poles that face the movable body in the coil axial direction of the coil, the shaft part supports the movable body at a position shifted from the center position of the movable body in a direction perpendicular to the axial direction of the shaft part, and the coil axis of the coil of the movable body is located at a position facing a switching position of the magnetic pole of the magnet.

First claim

What is claimed is:

1. A vibration actuator, comprising:
a movable body including a coil;
a fixed body including one or more magnets; and
a shaft part rotatably supporting the movable body, the movable body reciprocatingly and rotationally vibrating around the shaft part with respect to the fixed body by cooperation between the coil and the one or more magnets, wherein:
the one or more magnets are arranged in a direction orthogonal to an axial direction of the shaft part, each of the one or more magnets including two magnetic poles facing the movable body in a direction of a coil axis of the coil,
the shaft part supports the movable body at a position shifted from a center position of the movable body in the direction orthogonal to the axial direction of the shaft part,
the coil axis of the coil of the movable body is located at a position facing a switching position of the two magnetic poles of each of the one or more magnets,
the movable body includes a core around which the coil is wound, the core extending along the coil axis,
the core is rotatably supported by the shaft part on a side of one end of the core,
the one or more magnets include a first magnet and a second magnet disposed such that the core is placed between the first and the second magnets in an axial direction of the coil with two magnetic poles of the first magnet being disposed toward one of the both end parts of the core and two magnetic poles of the second magnet being disposed toward another one thereof, and
the switching positions of each of the first magnet and the second magnet are disposed such that they are positions facing a center of each of the magnetic poles of both end parts of the core.

2. The vibration actuator according to claim 1 , wherein the two magnetic poles of the first magnet and the two magnetic poles of the second magnet are disposed such that torque to be generated by cooperation with the coil when the coil is excited is generated in a same rotational direction.

3. The vibration actuator according to claim 1 , wherein:
the fixed body includes a case to which the shaft part is fixed and which rotatably houses the movable body, the case having a rectangular parallelepiped shape, wherein
the case has a rectangular parallelepiped shape extending in an axial direction of the coil, and
the movable body is movably disposed via the shaft part on a side of one end of the movable body in the case, and the movable body on a side of another end part thereof reciprocatingly and rotationally vibrates in a short-side direction of the case.

4. The vibration actuator according to claim 3 , wherein the movable body reciprocatingly and rotationally vibrates in the short-side direction of the case and comes in contact with an inner wall surface of the case.

5. The vibration actuator according to claim 3 , wherein:
at least one of the movable body and an inner wall surface of the case is provided with a buffer part, and
the movable body and the inner wall surface of the case come in contact with each other via the buffer part.

6. The vibration actuator according to claim 5 , wherein the buffer part is an elastomer.

7. The vibration actuator according to claim 5 , wherein the buffer part is a silicone rubber.

8. The vibration actuator according to claim 1 , wherein:
the coil is connected to a flexible substrate fixed to the fixed body on a side of one end of the flexible substrate, the coil being connected to the flexible substrate at another end part of the flexible substrate, and
the flexible substrate is provided with at least one curved part between the side of the one end and the other end part of the flexible substrate, the curved part having flexibility and being electrically connected to the coil from the side of the one end.

9. The vibration actuator according to claim 8 , wherein the at least one 1 curved part is disposed near the shaft part.

10. The vibration actuator according to claim 1 , wherein:
the shaft part is fixed to the fixed body and is rotatably inserted through the movable body via a bearing provided in the movable body, and
one of the shaft part and the bearing is formed by a non-magnetic material.

11. An electronic apparatus on which the vibration actuator according to claim 1 is mounted.

Assignees

• Takahashi Yuki
• Kagami Masaharu
• Ishitani Tomoya
• Kato Takanori
• Gomi Yoshihiro
• Minebea Mitsumi Inc

Inventors

• Takahashi Yuki
• Kagami Masaharu
• Ishitani Tomoya
• Kato Takanori
• Gomi Yoshihiro

Classifications

• B06B1/045

  using vibrating magnet, armature or coil system · CPC title

• H02K33/18 Primary

  with coil systems moving upon intermittent or reversed energisation thereof by interaction with a fixed field system, e.g. permanent magnets · CPC title