PRESS DETECTING DEVICE

• US 20170262113A1
• Filed: 05/23/2017
• Published: 09/14/2017
• Est. Priority Date: 12/17/2014
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Mori, Kenichi
• Granted Patent: US 10,289,232 B2
• Time in Patent Office: Days
• CPC Class Codes: B32B 1/00 Layered products having a non-planar shape
• CPC Class Codes: B32B 17/00 Layered products essentially comprising sheet glass, or glass, slag, or like fibres
• CPC Class Codes: B32B 2250/05 5 or more layers
• CPC Class Codes: B32B 2307/20 having particular electrical or magnetic properties, e.g. piezoelectric
• CPC Class Codes: B32B 2307/414 Translucent
• CPC Class Codes: B32B 2307/54 Yield strength; Tensile strength
• CPC Class Codes: B32B 2457/208 Touch screens
• CPC Class Codes: B32B 27/06 as the main or only constituent of a layer, which is next to another layer of the same or of a different material next to a layer of a particular substance B32B9/045; next to a bituminous or tarry layer B32B11/046; next to a water setting substance layer B32B13/12; next to a metal layer B32B15/08; next to a glass layer B32B17/10; next to a layer formed of natural mineral fibres or particles B32B19/045; next to a wood layer B32B21/08; next to a cellulosic plastic layer B32B23/08; next to a natural or synthetic rubber layer B32B25/08
• CPC Class Codes: B32B 27/36 comprising polyesters
• CPC Class Codes: B32B 3/08 characterised by added members at particular parts layer formed of separate pieces of material which are juxtaposed side-by-side B32B3/14, B32B3/18
• CPC Class Codes: B32B 7/12 using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: G01L 1/16 using properties of piezoelectric devices
• CPC Class Codes: G06F 2203/04105 Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

A touch input device that includes a housing; a touch detecting sensor having a piezoelectric film; a holding member; an interlayer pressure-sensitive adhesive that fixes the touch detecting sensor to the holding member; and a fixing adhesive that fixes the holding member to the housing. The interlayer pressure-sensitive adhesive has a large Young'"'"'s modulus at lower temperatures and a small Young'"'"'s modulus at higher temperatures. The fixing adhesive has a large Young'"'"'s modulus at lower temperatures and a small Young'"'"'s modulus at higher temperatures.

Claims

1. A press detecting device comprising:

a housing;

a press sensor having a piezoelectric film;

a holding member;

an interlayer pressure-sensitive adhesive that fixes the press sensor to the holding member, the interlayer pressure-sensitive adhesive having, relative to 20°

C., a larger Young'"'"'s modulus at temperatures below 20°

C. and a smaller Young'"'"'s modulus at temperatures above 20°

C.; and

a fixing adhesive that fixes the holding member to the housing, the fixing adhesive having, relative to 0°

C., a larger Young'"'"'s modulus at temperatures below 0°

C. and a smaller Young'"'"'s modulus at temperatures above 0°

C.

2. The press detecting device according to claim 1, wherein

the interlayer pressure-sensitive adhesive has a higher rate of change in Young'"'"'s modulus with respect to temperature at temperatures below 20°

C., and a lower rate of change in Young'"'"'s modulus with respect to temperature at temperatures above 20°

C., and

the fixing adhesive has a lower rate of change in Young'"'"'s modulus with respect to temperature at temperatures below 0°

C., and a higher rate of change in Young'"'"'s modulus with respect to temperature at temperatures above 0°

C.

3. The press detecting device according to claim 2, wherein an output voltage ratio of the press detection device across a temperature range of −

20°

C. to 60°

C. has an error range of ±

30%.

4. The press detecting device according to claim 1, wherein the interlayer pressure-sensitive adhesive has a higher rate of change in Young'"'"'s modulus with respect to temperature at temperatures below 20°

C., and a lower rate of change in Young'"'"'s modulus with respect to temperature at temperatures above 20°

C.

5. The press detecting device according to claim 1, wherein the fixing adhesive has a lower rate of change in Young'"'"'s modulus with respect to temperature at temperatures below 0°

C., and a higher rate of change in Young'"'"'s modulus with respect to temperature at temperatures above 0°

C.

6. The press detecting device according to claim 1, wherein the housing defines an opening and the holding member is disposed in the opening.

7. The press detecting device according to claim 6, wherein the housing includes a holding projection that projects toward an inside of the opening, and an outer circumferential edge of the holding member is fixed to the holding projection by the fixing adhesive.

8. The press detecting device according to claim 7, wherein the press sensor is fixed to the holding member by the interlayer pressure-sensitive adhesive such that the press sensor is within the housing.

9. The press detecting device according to claim 1, wherein the piezoelectric film is formed of chiral polymer.

10. The press detecting device according to claim 9, wherein the chiral polymer is polylactic acid.

11. A press detecting device comprising:

a housing;

a press sensor having a piezoelectric film;

a holding member;

an interlayer pressure-sensitive adhesive that fixes the press sensor to the holding member, the interlayer pressure-sensitive adhesive having, relative to 20°

C., a larger Young'"'"'s modulus at temperatures below 20°

C. and a smaller Young'"'"'s modulus at temperatures above 20°

C.; and

a fixing adhesive that fixes the holding member to the housing, the fixing adhesive having, relative to 20°

C., a larger Young'"'"'s modulus at temperatures below 20°

C. and a smaller Young'"'"'s modulus at temperatures above 20°

C.

12. The press detecting device according to claim 11, wherein

the interlayer pressure-sensitive adhesive has a higher rate of change in Young'"'"'s modulus with respect to temperature at temperatures below 20°

C., and a lower rate of change in Young'"'"'s modulus with respect to temperature at temperatures above 20°

C., and

the fixing adhesive has a higher rate of change in Young'"'"'s modulus with respect to temperature at temperatures below 20°

C., and a lower rate of change in Young'"'"'s modulus with respect to temperature at temperatures above 20°

C.

13. The press detecting device according to claim 12, wherein an output voltage ratio of the press detection device across a temperature range of −

20°

C. to 60°

C. has an error range of +20% to −

50%.

14. The press detecting device according to claim 11, wherein the interlayer pressure-sensitive adhesive has a higher rate of change in Young'"'"'s modulus with respect to temperature at temperatures below 20°

C., and a lower rate of change in Young'"'"'s modulus with respect to temperature at temperatures above 20°

C.

15. The press detecting device according to claim 11, wherein the fixing adhesive has a higher rate of change in Young'"'"'s modulus with respect to temperature at temperatures below 20°

C., and a lower rate of change in Young'"'"'s modulus with respect to temperature at temperatures above 20°

C.

16. The press detecting device according to claim 11, wherein the housing defines an opening and the holding member is disposed in the opening.

17. The press detecting device according to claim 16, wherein the housing includes a holding projection that projects toward an inside of the opening, and an outer circumferential edge of the holding member is fixed to the holding projection by the fixing adhesive.

18. The press detecting device according to claim 17, wherein the press sensor is fixed to the holding member by the interlayer pressure-sensitive adhesive such that the press sensor is within the housing.

19. The press detecting device according to claim 11, wherein the piezoelectric film is formed of chiral polymer.

20. The press detecting device according to claim 19, wherein the chiral polymer is polylactic acid.