Piezoelectric sounding component

Patent metadata

Field	Value
Publication number	US-10609490-B2
Application number	US-201815982425-A
Country	US
Kind code	B2
Filing date	May 17, 2018
Priority date	Sep 28, 2016
Publication date	Mar 31, 2020
Grant date	Mar 31, 2020

Abstract

A piezoelectric sounding component includes a diaphragm that includes a metal plate and a piezoelectric body formed on the metal plate. The diaphragm bends and vibrates according to application of voltage to the piezoelectric body. A casing that includes a bottom wall, side walls, and a supporting portion to support the diaphragm in inside edge portions of the side walls. The side walls extending from edges of the bottom wall in a thickness direction and includes a first wall, a second wall positioned to face the first wall, and a third wall positioned between the first wall. Two or more terminals that are formed on the first wall or the third wall serve to apply voltage to the diaphragm. Two or more elastic adhesives join the side walls and the diaphragm between the two or more terminals and the diaphragm. Two or more conductive adhesives are formed on the two or more elastic adhesives and join the two or more terminals and the diaphragm. The diaphragm is supported by the supporting portion and accommodated in the casing so that a gap formed between the first wall and the diaphragm is smaller than a gap formed between the second wall and the diaphragm.

First claim

The invention claimed is:

1. A piezoelectric sounding component, comprising:
(a) a diaphragm having first, second and third peripheral edge portions, the diaphragm comprising:
(i) a metal plate; and
(ii) a piezoelectric body formed on the metal plate, the diaphragm being adapted to vibrate in response to an application of voltage to the piezoelectric body;

(b) a casing comprising:
(i) a bottom wall and first, second and third side walls, the first and second side walls being spaced apart and facing one another and the third side wall extending between the first and second side walls such that the first and third side walls are adjacent one another;
(ii) a supporting portion which supports the first, second and third peripheral edge portions of the diaphragm at positions corresponding to the first, second and third side walls, respectively, the area of the first peripheral edge portion of the diaphragm supported by the supporting portion being greater than the area of the second peripheral edge portion of the diaphragm supported by the supporting portion;

(c) first and second terminals located on the first and third side walls, respectively;
(d) first and second elastic adhesives that join the diaphragm to the casing at locations corresponding to first and second terminals, respectively; and
(e) first and second conductive adhesives which extend over the first and second elastic adhesives, respectively, and which are electrically connect the first and second terminals to the diaphragm, respectively.

2. The piezoelectric sounding component according to claim 1 , wherein the casing further includes a fourth side wall extending between the first and second side walls, the fourth side wall facing and being spaced from the third side wall.

3. The piezoelectric sounding component according to claim 2 , wherein the bottom wall and the first, second, third and fourth side walls cooperate to form a sound chamber having an open end.

4. The piezoelectric sounding component according to claim 3 , wherein the supporting portion supports the diaphragm in such a manner that the diaphragm covers the open end of the sound chamber.

5. The piezoelectric sounding component according to claim 4 , wherein the sound chamber has a rectangular parallelepiped shape.

6. The piezoelectric sounding component according to claim 1 , wherein:
(a) a first gap is formed between the first peripheral edge portion of the diaphragm and the first side wall; and
(b) a second gap is formed between the second peripheral edge portion of the diaphragm and the second side wall, the size of first gap being smaller than the size of the second gap.

7. The piezoelectric sounding component according to claim 1 , wherein:
(a) the diaphragm has a fourth peripheral edge portion;
(b) the casing further comprises a fourth side wall which extends between the first and second side walls and is spaced from and faces the third side wall; and
(c) the area of the third peripheral edge portion of the diaphragm supported by the supporting portion is greater than the area of the fourth peripheral edge portion of the diaphragm supported by the supporting portion.

8. The piezoelectric sounding component according to claim 7 , wherein the bottom wall and the first, second, third and fourth side walls cooperate to form a sound chamber having an open end.

9. The piezoelectric sounding component according to claim 8 , wherein the supporting portion supports the diaphragm in such a manner that the diaphragm covers the open end of the sound chamber.

10. The piezoelectric sounding component according to claim 9 , wherein the sound chamber has a rectangular parallelepiped shape.

11. The piezoelectric sounding component according to claim 7 , wherein:
(a) a first gap is formed between the first peripheral edge portion of the diaphragm and the first side wall;
(b) a second gap is formed between the second peripheral edge portion of the diaphragm and the second side wall, the size of first gap being smaller than the size of the second gap;
(c) a third gap is formed between the third peripheral edge portion of the diaphragm and the third side wall; and
(d) a fourth gap is formed between the fourth peripheral edge portion of the diaphragm and the fourth side wall, the size of the third gap being greater than size of the fourth gap.

12. The piezoelectric sounding component according to claim 1 , wherein:
(a) the metal plate has a rectangular shape,
(b) the piezoelectric body is a circular plate located near a center of the metal plate; and
(c) one of the first and second conductive adhesives is formed near a center of the diaphragm.

13. The piezoelectric component according to claim 1 , where there is no electrode formed on the second side wall.

14. The piezoelectric component according to claim 7 , wherein there are no electrodes formed on the second and fourth side walls.

Assignees

• Murata Manufacturing Co

Inventors

• Murakami Junichi
• Yamauchi Masakazu

Classifications

• H04R31/00

  Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor {(manufacture of microstructural arrangements of deformable or non-deformable structures in general B81C1/00182)} · CPC title

• G10K9/22

  Mountings; Casings · CPC title

• H04R1/2811

  for loudspeaker transducers · CPC title

• H04R7/02

  characterised by the construction · CPC title

• H04R7/04

  Plane diaphragms · CPC title