Deformation sensor for string shape article

Patent metadata

Field	Value
Publication number	US-12072253-B2
Application number	US-202217839744-A
Country	US
Kind code	B2
Filing date	Jun 14, 2022
Priority date	Jun 1, 2020
Publication date	Aug 27, 2024
Grant date	Aug 27, 2024

Abstract

A sensor that includes a first film having a first main surface and a second main surface, the first film generating a charge according to a deformation amount of the first film; a first electrode on the first main surface; a second electrode on the second main surface; and a first fixing member and a second fixing member constructed to fix the first film, the first electrode, and the second electrode to an article. The first film is dimensioned to occupy an area equal to or more than half a peripheral surface of the article. The second electrode is located closer to the article than the first electrode. The first fixing member is separated from the second fixing member in an extending direction of the article.

First claim

The invention claimed is:

1. A sensor that detects deformation of an article having a string shape, the sensor comprising:
a first film having a first main surface and a second main surface, the first film generating a charge according to a deformation amount of the first film;
a first electrode on the first main surface;
a second electrode on the second main surface; and
a first fixing member and a second fixing member constructed to fix the first film, the first electrode, and the second electrode to the article,
wherein
the first film is dimensioned to occupy an area equal to or more than half a peripheral surface of the article,
the second electrode is located closer to the article than the first electrode, and
the first fixing member is separated from the second fixing member in an extending direction of the article.

2. The sensor according to claim 1 , wherein the first film has a cylindrical shape matching the peripheral surface of the article.

3. The sensor according to claim 2 , wherein the first film has is dimensioned to wrap around the peripheral surface of the article a single time.

4. The sensor according to claim 1 , wherein the first film is a piezoelectric film.

5. The sensor according to claim 4 , wherein the first film is a PLLA film.

6. The sensor according to claim 5 , wherein an orientation direction of the first film is at an angle of 45 degrees with respect to the extending direction of the article.

7. The sensor according to claim 6 , further comprising:
a second film having a third main surface and a fourth main surface, the second film generating a charge according to a deformation amount of the second film;
a third electrode on the third main surface; and
a fourth electrode on the fourth main surface, wherein
the second film is a PLLA film,
the second film has a cylindrical shape matching a peripheral surface of the first electrode,
the fourth electrode is located closer to the article than the third electrode, and
an orientation direction of the second film is parallel to the extending direction of the article.

8. The sensor according to claim 7 , wherein the second film has is dimensioned to wrap around the peripheral surface of the first electrode a single time.

9. The sensor according to claim 5 , wherein an orientation direction of the first film is parallel to the extending direction of the article.

10. The sensor according to claim 9 , further comprising:
a second film having a third main surface and a fourth main surface, the second film generating a charge according to a deformation amount of the second film;
a third electrode on the third main surface; and
a fourth electrode on the fourth main surface, wherein
the second film is a PLLA film,
the second film has a cylindrical shape matching a peripheral surface of the first electrode,
the fourth electrode is located closer to the article than the third electrode, and
an orientation direction of the second film forms an angle of 45 degrees with respect to the extending direction of the article.

11. The sensor according to claim 10 , wherein the second film has is dimensioned to wrap around the peripheral surface of the first electrode a single time.

12. The sensor according to claim 4 , wherein the first film is a PVDF film.

13. The sensor according to claim 12 , wherein an orientation direction of the first film forms an angle of 45 degrees with respect to the extending direction of the article.

14. The sensor according to claim 12 , wherein an orientation direction of the first film is parallel to the extending direction of the article.

15. The sensor according to claim 1 , wherein
the first film has a first end portion and a second end portion in the extending direction,
the first fixing member is in contact with the first end portion, and
the second fixing member is in contact with the second end portion.

16. The sensor according to claim 1 , wherein the first fixing member and the second fixing member do not overlap a center of the first film in the extending direction as viewed in a direction normal to the first main surface of the first film.

17. The sensor according to claim 1 , wherein the first fixing member and the second fixing member do not overlap the second electrode when viewed in a direction normal to the first main surface of the first film.

18. The sensor according to claim 1 , further comprising
a third fixing member, wherein
the first fixing member, the second fixing member, and the third fixing member are arranged in this order in the extending direction,
the third fixing member is separated from the second fixing member in the extending direction, and
the third fixing member fixes the first film, the first electrode, and the second electrode to the article.

19. The sensor according to claim 1 , wherein
the first electrode is a ground electrode, and
the second electrode is a signal electrode.

Assignees

• Murata Manufacturing Co

Inventors

• Mori Kenichi

Classifications

• H10N30/857

  Macromolecular compositions · CPC title

• H10N30/302

  Sensors · CPC title

• H10N30/87

  Electrodes or interconnections, e.g. leads or terminals · CPC title

• G01B7/16

  for measuring the deformation in a solid, e.g. by resistance strain gauge · CPC title

• G01L1/16 Primary

  using properties of piezoelectric devices · CPC title