Pressure-sensitive sensor

Patent metadata

Field	Value
Publication number	US-9645032-B2
Application number	US-201314655831-A
Country	US
Kind code	B2
Filing date	Dec 26, 2013
Priority date	Dec 28, 2012
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

The present invention achieves a pressure-sensitive sensor which can detect information on a pressure, a sound pressure, acceleration, gas and the like, with high sensitivity. The pressure-sensitive sensor includes: a cantilever ( 22 ); a frame ( 23 ) which is provided around the cantilever ( 22 ) and holds a base end of the cantilever ( 22 ); a gap ( 24 ) formed between the cantilever ( 22 ) and the frame ( 23 ); and a liquid ( 28 ) which seals the gap ( 24 ).

First claim

The invention claimed is:

1. A pressure-sensitive sensor comprising:
a cantilever;
a frame which is provided around the cantilever and holds a base end of the cantilever;
a gap formed between the cantilever and the frame; and
a liquid which seals the gap.

2. The pressure-sensitive sensor according to claim 1 , wherein
the gap is held in a state of being sealed by the liquid, regardless of a deformation of the cantilever.

3. The pressure-sensitive sensor according to claim 1 , wherein
a liquid retaining region which includes a surface of the cantilever and the gap, and a liquid expelling region which is formed around the liquid retaining region are provided.

4. The pressure-sensitive sensor according to claim 1 , wherein
a gas chamber which is connected to the gap is provided in a rear face side of the cantilever.

5. The pressure-sensitive sensor according to claim 4 , wherein
a film having flexibility is provided so as to cover the liquid, and outside pressure is transmitted to the liquid through the film.

6. The pressure-sensitive sensor according to claim 4 , wherein
the liquid is provided locally with respect to the gap, and the outside pressure is transmitted directly to the cantilever.

7. The pressure-sensitive sensor according to claim 4 , further comprising a protection mechanism which limits the deformation of the cantilever within a fixed range and thereby protects the cantilever.

8. The pressure-sensitive sensor according to claim 1 , wherein
a temperature compensation system for compensating temperature characteristics of the cantilever is provided.

9. The pressure-sensitive sensor according to claim 8 , wherein
the temperature compensation system has a non-deforming type dummy cantilever that has characteristics similar to resistance variation characteristics with respect to temperature, which the cantilever has.

10. The pressure-sensitive sensor according to claim 4 , wherein
the pressure-sensitive sensor is arranged in a liquid tank and detects a pressure which travels in the liquid in the liquid tank.

11. The pressure-sensitive sensor according to claim 10 , wherein
the pressure-sensitive sensor is a hydrophone which detects a sound wave that travels in the liquid.

12. The pressure-sensitive sensor according to claim 11 , wherein
the hydrophone has a sound guide which guides the sound wave to the cantilever.

13. A sensor array, wherein
the pressure-sensitive sensors according to claim 1 are arrayed one-dimensionally or two-dimensionally.

14. The pressure-sensitive sensor according to claim 1 , wherein
the liquid has an adsorbing molecule which adsorbs a gas component to be detected, on a liquid surface.

15. The pressure-sensitive sensor according to claim 14 , further comprising:
a gas chamber which is formed in a rear face side of the cantilever so that gas can flow through the gap;
a through hole which connects the inside of the gas chamber and the outside; and
a filter which is provided in the through hole and through which gases except the gas component to be detected can pass.

16. A method of using a pressure-sensitive sensor, in which the pressure-sensitive sensor includes:
a cantilever;
a frame which is provided around the cantilever and holds a base end of the cantilever; and a gap formed between the cantilever and the frame, the method comprising:
a step of sealing the gap by a liquid so that an interface of the liquid in the gap stays inside or in a vicinity of the gap, regardless of a deformation of the cantilever, and thereby maintaining a sealed state of the gap; and
a step of detecting the deformation of the cantilever, which occurs due to a force exerted from the outside, in the sealed state, as a change of electrical characteristics that the cantilever has.

Assignees

• Univ Tokyo

Inventors

• Shimoyama Isao
• Matsumoto Kiyoshi
• Nguyen Binh-Khiem
• NGUYEN Minh-Dung
• PHAN Hoang-Phuong

Classifications

• B81B2203/0118

  Cantilevers · CPC title

• H04R1/42

  Combinations of transducers with fluid-pressure or other non-electrical amplifying means · CPC title

• B81B3/0027

  Structures for transforming mechanical energy, e.g. potential energy of a spring into translation, sound into translation · CPC title

• H04R2217/01

  Non-planar magnetostrictive, piezoelectric or electrostrictive benders · CPC title

• G01V1/186

  Hydrophones · CPC title