Sensor and gripping load detection device

Patent metadata

Field	Value
Publication number	US-2025151626-A1
Application number	US-202419003458-A
Country	US
Kind code	A1
Filing date	Dec 27, 2024
Priority date	Jul 6, 2022
Publication date	May 8, 2025
Grant date	—

Abstract

A sensor includes a piezoelectric film having a first and second main surfaces facing each other in a first direction, a first electrode on the first main surface, a second electrode on the second main surface, and a wiring portion. The first electrode and the second electrode overlap each other in the first direction and include a first portion overlapping the piezoelectric film and a second portion that does not overlap the piezoelectric film, the first portion and the second portion are arranged in a second direction orthogonal to the first direction, and the wiring portion includes a wiring substrate overlapping the second portion in the first direction and having a third and a fourth main surface, a first conductor on the third main surface and electrically connected to the first electrode, and a second conductor on the fourth main surface and electrically connected to the second electrode.

First claim

1 . A sensor comprising:
a piezoelectric film having a first main surface and a second main surface facing each other in a first direction; a first electrode on the first main surface; a second electrode on the second main surface; and a wiring portion, wherein the first electrode and the second electrode overlap each other as viewed in the first direction and include a first portion that overlaps the piezoelectric film and a second portion that does not overlap the piezoelectric film, the first portion and the second portion being arranged in a second direction orthogonal to the first direction, and the wiring portion includes:
a wiring substrate that is an insulator, the wiring substrate overlapping the second portion as viewed in the first direction and having a third main surface and a fourth main surface facing each other in the first direction;
a first conductor on the third main surface and electrically connected to the first electrode; and
a second conductor on the fourth main surface and electrically connected to the second electrode.

2 . The sensor according to claim 1 , wherein a length in a third direction orthogonal to the first direction and the second direction of the second portion is shorter than a length in the third direction of the first portion.

3 . The sensor according to claim 1 , wherein the first portion is transparent.

4 . The sensor according to claim 1 , wherein the first portion has a rectangular shape as viewed in the first direction.

5 . The sensor according to claim 4 , wherein the first portion has a long side extending in the second direction and a short side extending in a third direction orthogonal to the first direction and the second direction as viewed in the first direction.

6 . The sensor according to claim 1 , wherein the second portion has a rectangular shape as viewed in the first direction.

7 . The sensor according to claim 6 , wherein the second portion has a long side extending in the second direction and a short side extending in a third direction orthogonal to the first direction and the second direction as viewed in the first direction.

8 . The sensor according to claim 1 , wherein
the first portion includes a first end in one direction of a third direction orthogonal to the first direction and the second direction and includes a second end in an opposite direction to the one direction, the second portion includes a third end in the one direction and a fourth end in the opposite direction, the first end is located further in the one direction than the third end as viewed in the first direction, and the second end is located further in the opposite direction than the fourth end as viewed in the first direction.

9 . The sensor according to claim 1 , wherein
the first portion includes a third portion and a fourth portion, the fourth portion is located between the second portion and the third portion, and a length in a third direction orthogonal to the first direction and the second direction of the fourth portion is shorter than a length in the third direction of the third portion.

10 . The sensor according to claim 1 , wherein the wiring substrate is a flexible substrate.

11 . The sensor according to claim 1 , wherein the wiring portion further includes:
a first conductive adhesive material that overlaps the second portion as viewed in the first direction and is on an end surface in one direction in the first direction of the first conductor; and a second conductive adhesive material that overlaps the second portion as viewed in the first direction and is on an end surface in an opposite direction to the one direction of the second conductor,
the first electrode, the first conductive adhesive material, the first conductor, the wiring substrate, the second conductor, the second conductive adhesive material, and the second electrode are arranged in this order along the first direction in a fifth portion overlapping the second portion as viewed in the first direction,
the first conductor is electrically connected to the first electrode via the first conductive adhesive material, and
the second conductor is electrically connected to the second electrode via the second conductive adhesive material.

12 . The sensor according to claim 11 , wherein
a position in the second direction where the fifth portion exists as viewed in the first direction is defined as a first position, and a length in a third direction orthogonal to the first direction and the second direction of the wiring substrate at the first position is longer than a length in the third direction of the second portion at the first position.

13 . The sensor according to claim 12 , wherein
a length in the third direction of the first conductive adhesive material at the first position is shorter than a length in the third direction of the second portion at the first position, and a length in the third direction of the second conductive adhesive material at the first position is shorter than a length in the third direction of the second portion at the first position.

14 . The sensor according to claim 11 , wherein
a position in the second direction where the fifth portion exists as viewed in the first direction is defined as a first position, a length in a third direction orthogonal to the first direction and the second direction of the first conductive adhesive material at the first position is shorter than a length in the third direction of the second portion at the first position, and a length in the third direction of the second conductive adhesive material at the first position is shorter than a length in the third direction of the second portion at the first position.

15 . A gripping load detection device comprising:
the sensor according to claim 1 ; a transmissive housing that has a tubular shape; and a grip constructed to be gripped by a user, the grip covering a periphery of a part of an outer surface of the transmissive housing, wherein the sensor is on the outer surface, the first portion is in a first region that does not overlap the grip as viewed in a normal direction of the outer surface, and the wiring portion is in a second region overlapping the grip as viewed in the normal direction, and is not in the first region.

16 . The gripping load detection device according to claim 15 , further comprising:
a light emitter in a hollow portion of the transmissive housing and surrounded by an inner surface of the transmissive housing wherein the sensor outputs a deformation detection signal corresponding to a twisting amount of the transmissive housing, the light emitter is in the first region, and the light emitter emits light based on the deformation detection signal.

17 . The gripping load detection device according to claim 15 , wherein
the outer surface includes a polygonal flat surface, and the second portion is on the polygonal flat surface.

18 . The gripping load detection device according to claim 15 , wherein
the first electrode is a ground electrode electrically connected to ground potential, the second electrode is a signal electrode that outputs a deformation detection signal corresponding to a twisting amount of the transmissive housing, and an end surface in the first direction of the second electrode is fixed to the outer surface.

Assignees

• Murata Manufacturing Co

Inventors

• Mori Kenichi
• Kubo Hiroyuki

Classifications

• H10N30/302

  Sensors · CPC title

• H10N30/875 Primary

  Further connection or lead arrangements, e.g. flexible wiring boards, terminal pins · CPC title

• H10N30/857

  Macromolecular compositions · CPC title

• H10N30/87

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

• G01B7/16 Primary

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