Actuator and electrical appliance having fixed member with a coil and movable members having magnets

• US 9,755,491 B2
• Filed: 01/29/2013
• Issued: 09/05/2017
• Est. Priority Date: 01/30/2012
• Status: Active Grant

• Current Assignee: Mitsumi Electric Co., Ltd. (Minebea Mitsumi, Inc.)
• Original Assignee: Mitsumi Electric Co., Ltd. (Minebea Mitsumi, Inc.)
• Inventors: Takahashi, Yuki, Inamoto, Shigenori, Kitamura, Yasutaka
• Primary Examiner(s): Benitez-Rosario, Joshua
• Assistant Examiner(s): JOHNSON, RASHAD H
• Application Number:
  US13/752,648
• Publication Number:
  US 20130193780A1
• Time in Patent Office: 1,680 Days
• Field of Search: 310 15, 310 25, 310 28, 310 51, 310 81, 310 91, 335185, 335 19, 335193
• CPC Class Codes: B06B 1/045 using vibrating magnet, armature or coil system
• CPC Class Codes: H02K 33/00 Motors with reciprocating, oscillating or vibrating magnet, armature or coil system arrangements for handling mechanical energy structurally associated with motors H02K7/00, e.g. H02K7/06
• CPC Class Codes: H02K 33/16 with polarised armatures moving in alternate directions by reversal or energisation of a single coil system
• CPC Class Codes: H02K 5/04 Casings or enclosures characterised by the shape, form or construction thereof
• CPC Class Codes: H02K 5/24 specially adapted for suppression or reduction of noise or vibrations

Abstract

An actuator includes a fixed section that includes a spindle and a coil fixed to the spindle, a first movable section that includes a first magnet magnetized in an inside-outside direction and disposed to cover the outer peripheral surface of one end in an axial direction of the fixed section, that is mounted on the spindle in an elastically-maintained state, and that is movable in the axial direction, and a second movable section that includes a second magnet magnetized in the inside-outside direction and disposed to cover the outer peripheral surface of the other end in the axial direction of the fixed section, that is mounted on the spindle in an elastically-maintained state, and that is movable in the axial direction. When current flows in the coil, the first movable section and the second movable section move in the opposite directions.

Claims

1. An actuator comprising:

a fixed section that includes a spindle, a coil fixed to the spindle, a partition wall disposed at a center of the spindle, a first spring stopping member disposed at one end of the spindle, and a second spring stopping member disposed at another end of the spindle;

a first movable section that includes;

a first magnet magnetized in an inside-outside direction and disposed to cover the outer peripheral surface of one end in an axial direction of the fixed section;

a first output connection portion to which a movable member of an electrical appliance is attached,

the first movable section being mounted on the spindle in an elastically-maintained state between the partition wall and the first spring stopping member by a first compression coil spring inserted over the spindle between the partition wall and the first movable section and by another first compression coil spring inserted over the spindle between the first spring stopping member and the first movable section, and the first movable section being movable in the axial direction; and

a second movable section that includes;

a second magnet magnetized in the inside-outside direction and disposed to cover the outer peripheral surface of the other end in the axial direction of the fixed section;

a second output connection portion to which a movable member of an electrical appliance is attached,

the second movable section being mounted on the spindle in an elastically-maintained state between the partition wall and the second spring stopping member by a second compression coil spring inserted over the spindle between the partition wall and the second movable section and by another second compression coil spring inserted over the spindle between the second spring stopping member and the second movable section, and the second movable section being movable in the axial direction,

wherein;

the first movable section and the second movable section are arranged symmetrically in the axial direction with respect to the partition wall,

the first output connection portion and the second output connection portion each have an attachment portion projecting in a direction orthogonal to a movement direction of the first movable section and the second movable section, and

when current flows in the coil, the first movable section and the second movable section move in opposite directions.

2. The actuator according to claim 1, wherein the first magnet and the second magnet generate magnetic fields vertically traversing current flowing in the coil, and

wherein when current flows in the coil, a thrust generated in the first movable section in accordance with Fleming'"'"'s left-hand law and a thrust generated in the second movable section have opposite directions.

3. The actuator according to claim 2, wherein the first movable section includes a first outer yoke disposed on the outer peripheral surface of the first magnet or a first inner yoke disposed on the inner peripheral surface of the first magnet with the coil interposed therebetween, and

wherein the second movable section includes a second outer yoke disposed on the outer peripheral surface of the second magnet or a second inner yoke disposed on the inner peripheral surface of the second magnet with the coil interposed therebetween.

4. The actuator according to claim 2, wherein the coil is wound in the same direction over the entire length of the fixed section, and

wherein the magnetization direction of the first magnet and the magnetization direction of the second magnet are opposite to each other.

5. The actuator according to claim 2, wherein the coil includes a first coil which is wound to correspond to the first magnet and in which current flows in a first direction, and a second coil which is wound to correspond to the second magnet and in which current flows in a second direction opposite to the first direction, and

wherein the magnetization direction of the first magnet and the magnetization direction of the second magnet are the same.

6. The actuator according to claim 1, wherein the fixed section is an electromagnet in which the coil is wound on the outer peripheral surface of a core formed of a magnetic material,

wherein the magnetization direction of the first magnet and the magnetization direction of the second magnet are opposite to each other, and

wherein when current flows in the coil and both ends of the core are magnetized to opposite polarities, an attractive force or a repulsive force acting between the first magnet and the core and an attractive force or a repulsive force acting between the second magnet and the core have opposite direction to each other.

7. The actuator according to claim 1, wherein the first magnet and the second magnet are constructed by combining a plurality of segment type magnets.

8. The actuator according to claim 1, wherein the first magnet and the second magnet are anisotropic magnets.

9. The actuator according to claim 1, wherein the coil is driven substantially at a resonance frequency.

10. An electrical beauty appliance comprising the actuator according to claim 1.