Pressure sensing element and safety apparatus including same

Patent metadata

Field	Value
Publication number	US-2018348072-A1
Application number	US-201515757526-A
Country	US
Kind code	A1
Filing date	Dec 21, 2015
Priority date	Sep 3, 2015
Publication date	Dec 6, 2018
Grant date	—

Abstract

The present invention relates to a pressure sensing element having an expanded pressure sensing section and a safety apparatus including the same. A pressure sensing element, according to an embodiment of the present invention, comprises: an intermediate layer having a structure in which at least two functional layers are stacked on each other; a first electrode layer disposed on one surface of the intermediate layer and including a plurality of first electrode patterns; and a second electrode layer disposed on an opposite surface of the intermediate layer to overlap the first electrode layer with the intermediate layer between the first and second electrode layers, wherein among the two functional layers, the first functional layer has a thickness linearly varying in a first pressure section, and the second functional layer has a thickness linearly varying in a second pressure section; the maximum pressure in the first pressure section is lower than that in the second pressure section; and the minimum pressure in the second pressure section is included in the first pressure section.

First claim

1 . A pressure sensing element comprising:
an intermediate layer having a structure in which at least two functional layers are stacked; a first electrode layer disposed on one surface of the intermediate layer and including a plurality of first electrode patterns; and a second electrode layer disposed on the other surface of the intermediate layer to overlap the first electrode layer with the intermediate layer between the first electrode layer and the second electrode layer, wherein among the at least two functional layers, a first functional layer has a thickness linearly varying in a first pressure section and a second functional layer has a thickness linearly varying in a second pressure section, and a maximum pressure in the first pressure section is lower than a maximum pressure in the second pressure section and a minimum pressure in the second pressure section is included in the first pressure section.

2 . The pressure sensing element of claim 1 , wherein the maximum pressure in the first pressure section is equivalent to the minimum pressure in the second pressure section.

3 . The pressure sensing element of claim 1 , wherein the intermediate layer has a thickness linearly varying in a third pressure section including a range of a minimum pressure in the first pressure section to the maximum pressure in the second pressure section.

4 . The pressure sensing element of claim 1 , wherein the intermediate layer has a structure in which the first functional layer is disposed on the second functional layer.

5 . The pressure sensing element of claim 4 , wherein CFD first functional layer 25%, which is a pressure at which the thickness of the first functional layer is reduced by 25%, and CFD second functional layer 25%, which is a pressure at which the thickness of the second functional layer is reduced by 25%, satisfy the following Expression 1:
1<CFD second functional layer 25%/CFD first functional layer 25%≤20,  [Expression 1]
(Compression Force Deflection; CFD).

6 . The pressure sensing element of claim 4 , wherein, when a third functional layer is further disposed below the second functional layer, a maximum pressure in a fourth pressure section in which a thickness of the third functional layer linearly varies is higher than the maximum pressure in the second pressure section and a minimum pressure in the fourth pressure section is included in the second pressure section.

7 . The pressure sensing element of claim 6 , wherein the intermediate layer includes the second pressure section and has a thickness linearly varying in a third pressure section including a range of a minimum pressure in the first pressure section to the maximum pressure in the fourth pressure section.

8 . The pressure sensing element of claim 6 , wherein CFD first functional layer 25%, which is a pressure at which the thickness of the first functional layer is reduced by 25%, and CFD third functional layer 25%, which is a pressure at which the thickness of the third functional layer is reduced by 25%, satisfy the following Expression 2:
1<CFD third functional layer 25%/CFD first functional layer 25%≤20.  [Expression 2]

9 . The pressure sensing element of claim 1 , further comprising an adhesion layer disposed between the first functional layer and the second functional layer.

10 . The pressure sensing element of claim 1 , wherein the first and second functional layers include a conductive filler.

11 . The pressure sensing element of claim 1 , wherein the first electrode patterns and second electrode patterns are arranged in the same direction.

12 . The pressure sensing element of claim 1 , wherein:
the first electrode patterns are arranged in a first direction; and second electrode patterns are arranged in a second direction crossing the first direction.

13 . A safety apparatus comprising:
a pressure sensing element including an intermediate layer having a structure in which at least two functional layers are stacked, a first electrode layer disposed on one surface of the intermediate layer and including a plurality of first electrode patterns, and a second electrode layer disposed on the other surface of the intermediate layer to overlap the first electrode layer with the intermediate layer between the first electrode layer and the second electrode layer, wherein among the at least two functional layers, a first functional layer has a thickness linearly varying in a first pressure section, a second functional layer has a thickness linearly varying in a second pressure section, a maximum pressure in the first pressure section is lower than a maximum pressure in the second pressure section, and a minimum pressure in the second pressure section is included in the first pressure section; a control unit configured to generate a control signal according to a change in a thickness of the intermediate layer; and an output unit configured to output the control signal.

14 . The safety apparatus of claim 13 , wherein the control unit measures a pressure applied to the pressure sensing element according to the thickness of the intermediate layer and generates a control signal according to the measured pressure.

15 . The safety apparatus of claim 13 , wherein the maximum pressure in the first pressure section in the pressure sensing element is equivalent to the minimum pressure in the second pressure section.

16 . The safety apparatus of claim 13 , wherein the intermediate layer of the pressure sensing element has a thickness linearly varying in a third pressure section including a range of a minimum pressure in the first pressure section to the maximum pressure in the second pressure section.

17 . The safety apparatus of claim 13 , wherein, when a third functional layer is further disposed below the second functional layer, a maximum pressure in a fourth pressure section in which a thickness of the third functional layer linearly varies is higher than the maximum pressure in the second pressure section and a minimum pressure in the fourth pressure section is included in the second pressure section.

18 . The safety apparatus of claim 13 , wherein the intermediate layer of the pressure sensing element includes the second pressure section and has a thickness linearly varying in a third pressure section including a range of a minimum pressure in the first pressure section to a maximum pressure in a fourth pressure section.

19 . The safety apparatus of claim 13 , wherein the first electrode patterns and second electrode patterns are arranged in the same direction.

20 . The safety apparatus of claim 13 , wherein:
the first electrode patterns are arranged in a first direction; and second electrode patterns are arranged in a second direction crossing the first direction.

Assignees

• Lg Innotek Co Ltd

Inventors

• Kim Bi Yi
• Kim Jeong Han
• Park Hyun Gyu
• Cho Won Keun
• Cho In Hee
• Jo Hyun Jin
• Hong Seung Kwon

Classifications

• G01L5/22

  for measuring the force applied to control members, e.g. control members of vehicles, triggers · CPC title

• G01L1/14 Primary

  by measuring variations in capacitance or inductance of electrical elements, e.g. by measuring variations of frequency of electrical oscillators · CPC title

• G01L1/142 Primary

  using capacitors · CPC title

• G01L1/2287

  constructional details of the strain gauges (adjustable resistors H01C10/00) · CPC title

• G01L1/18

  using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material · CPC title