Linear actuator

Patent metadata

Field	Value
Publication number	US-10411575-B2
Application number	US-201515127161-A
Country	US
Kind code	B2
Filing date	Mar 17, 2015
Priority date	Mar 17, 2014
Publication date	Sep 10, 2019
Grant date	Sep 10, 2019

Abstract

A linear actuator may include a stator; a movable element; a spring member connected to the movable element and the stator and structured to support the movable element in such a way as to be movable with respect to the stator in a direction of an axis line; a magnetic drive mechanism structured to drive the movable element in the direction of the axis line; and a gel damper member placed at a position on a center line of the movable element or one of a group of positions surrounding the center line, between the stator and the movable element.

First claim

What is claimed is:

1. A linear actuator comprising: a stator; a movable element; a spring member connected to the movable element and the stator, and structured to support the movable element in such a way as to be movable with respect to the stator in a direction of an axis line: a magnetic drive mechanism structured to drive the movable element in the direction of the axis line; and a gel damper member placed position on a center line of the movable element or one of a group of positions surrounding the center line, between the stator and the movable element; wherein the gel damper member is adhered and fixed to both the movable element and the stator, wherein, the stator comprises a supporting shaft that stretches on the center line; the movable element comprises a shaft hole, which stretches on the center line, and inside which the supporting shaft is placed; and the gel damper member is cylindrically placed between an outer circumferential surface of the supporting shaft and an inner circumferential surface of the shaft hole.

2. The linear actuator according to claim 1 ;
wherein, the spring member is a plate-like spring component comprising: a stator side connection part connected to the stator; a movable element side connection part connected to the movable element; and an arm part connected to the stator side connection part and the movable element side connection part.

3. The linear actuator according to claim 1 ;
wherein, the stator comprises a stator side facing part that faces the movable element in the direction of the axis line; and
the gel damper member is placed between the stator side facing part and the movable element in the direction of the axis line.

4. The linear actuator according to claim 3 ;
wherein, a needle entering level of the gel damper member is a level of 90 to 110 as specified in the JIS-K-2207 standard or the JIS-K-2220 standard.

5. The linear actuator according to claim 3 ;
wherein, the movable element comprises a shaft part protruding toward the stator side facing part on the center line, and
the gel damper member is placed between an end surface of the shaft part at a side toward the stator side facing part, and the stator side facing part, in the direction of the axis line.

6. The linear actuator according to claim 3 ;
wherein, the movable element comprises a shaft part protruding toward the stator side facing part on the center line, and
the gel damper member is placed in such a way as to surround the shaft part.

7. The linear actuator according to claim 3 ;
wherein, the movable element comprises; a shaft that constitutes the shaft part with one end of the shaft; a permanent magnet constituting the magnetic drive mechanism and having a center hole formed, inside which the shaft is set; a yoke that is provided with an end plate part contacting the permanent magnet at one side in the direction of the axis line, and a cylinder part covering the permanent magnet at an outside in a radial direction; and a washer that contacts a circumference of the center hole of the permanent magnet, at the other side in the direction of the axis line; and
the shaft is welded to the end plate part at the one side in the direction of the axis line, and welded to the washer at the other side in the direction of the axis line.

8. The linear actuator according to claim 3 ;
wherein, the gel damper member is made from silicone gel.

9. The linear actuator according to claim 1 ; wherein, the movable element comprises: a tubular sleeve provided with the shaft hole; a permanent magnet constituting the magnetic drive mechanism and having a center hole formed, inside which the tubular sleeve is set; a yoke that is provided with an end plate part contacting the permanent magnet at one side in the direction of the axis line, and a cylinder part covering the permanent magnet at an outside in a radial direction; and a washer that contacts a circumference of the center hole of the permanent magnet, at the other side in the direction of the axis line; and the tubular sleeve is welded to the end plate part at the one side in the direction of the axis line, and welded to the washer at the other side in the direction of the axis line.

10. A linear actuator comprising: a stator; a movable element; a spring member connected to the movable element and the stator, and structured to support the movable element in such a way as to be movable with respect to the stator in a direction of an axis line: a magnetic drive mechanism structured to drive the movable element in the direction of the axis line; and a gel damper member placed between the stator and the movable element; wherein, a position of a gravity center of the movable element and a connecting position of the spring member in relation to the movable element are distant from each other in the direction of the axis line; wherein the gel damper member is fixed to both the movable element and the stator, wherein, the stator comprises a supporting shaft that stretches on the center line; the movable element comprises a shaft hole, which stretches on the center line, and inside which the supporting shaft is placed; and the gel damper member is cylindrically placed between an outer circumferential surface of the supporting shaft and an inner circumferential surface of the shaft hole.

11. The linear actuator according to claim 10 ;
wherein, the spring member is a plate-like spring component having its thickness direction in a direction along the direction of the axis line; and the spring member comprises: a stator side connection part connected to the stator; a movable element side connection part connected to the movable element; and an arm part connected to the stator side connection part and the movable element side connection part.

12. The linear actuator according to claim 10 ;
wherein, the magnetic drive mechanism comprises a permanent magnet provided to the movable element, and a coil provided to the stator and facing the permanent magnet in a radial direction.

13. The linear actuator according to claim 10 ;
wherein, the gel damper member is placed at least, at either one of a position on a center line of the movable element or one of a group of positions surrounding the center line.

14. The linear actuator according to claim 13 ;
wherein, the stator comprises a stator side facing part that faces the movable element in the direction of the axis line; and
the gel damper member is placed between the stator side facing part and the movable element in the direction of the axis line.

15. The linear actuator according to claim 14 ;
wherein, the movable element comprises a shaft part protruding toward the stator side facing part on the center line, and
the gel damper member is placed between an end surface of the shaft part at a side toward the stator side facing part, and the stator side facing part, in the direction of the axis line.

16. The linear actuator according to claim 14 ;
wherein, the gel damper member is placed at three positions surrounding the center line.

17. The linear actuator according to claim 13 ;
wherein, the stator comprises a supporting shaft that stretches on the center line;
the movable element comprises a shaft hole, which stretches on the center line, and inside which the supporting shaft is placed; and
the gel damper member is cylindrically placed between an outer circumferential surface of the supporting shaft and an inner circumferential surface of the shaft hole.

18. The linear actuator according to claim 10 ;
wherein, the gel damper member is made from si

Assignees

• Nidec Sankyo Corp

Inventors

• Takeda Tadashi
• Kitahara Hiroshi
• Sue Takeshi

Classifications

• H02K33/02

  with armatures moved one way by energisation of a single coil system and returned by mechanical force, e.g. by springs · CPC title

• H02K7/086

  radially supporting the rotor around a fixed spindle; radially supporting the rotor directly (H02K7/09 takes precedence) · CPC title

• H02K5/24

  specially adapted for suppression or reduction of noise or vibrations · CPC title

• H01F7/1615

  Armatures or stationary parts of magnetic circuit having permanent magnet · CPC title

• H01F7/088 Primary

  provided with means for absorbing shocks · CPC title