JP2012198051A - Electrostatic capacitance type sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic capacitance type sensor whose dielectric layer is difficult to be prevented from deformation and whose cover member does not allow easy extension of cleavage.SOLUTION: An electrostatic capacitance type sensor 1 comprises: a foam-made dielectric layer 2; a cover member 3 having a front side base material 30 arranged on the front side of the dielectric layer 2 and a rear side base material 31 arranged on the rear side of the dielectric layer 2; two side adhesive members 80 to 88 arranged inside a readily cleavable part out of the whole external edge of the cover member 3 and on the circumference of the dielectric layer 2 and having a front side adhesive layer 830 adhered to the rear face of the front side base material 30, a rear side adhesive layer 831 adhered to the front face of the rear side base material 31, and a core material layer 832 intervening between the front side adhesive layer 830 and the rear side adhesive layer 831; and through holes 90 to 94 demarcated between a pair of adjoining circumferential edge parts 800 and 810 of the two side adhesive members 80 to 88 and securing gas passages to the dielectric layer 2.

Description

  The present invention relates to a capacitive sensor having a dielectric layer made of foam.

  For example, Patent Document 1 discloses a capacitive sensor that includes a plurality of front electrodes, a plurality of back electrodes, and a dielectric layer. In paragraph [0099] of the same document, a foam is exemplified as a material of the dielectric layer. The foam includes a large number of cells (holes). When the foam is elastically deformed, the volume of the cell changes. That is, when a load is applied to the capacitive sensor, the dielectric layer is compressed. At this time, many cells of the foam are crushed. The cell volume is reduced. On the other hand, when a load is no longer applied to the capacitive sensor, the dielectric layer expands in an attempt to return to its original shape due to the elastic restoring force accumulated during compression. At this time, many cells of the foam expand. The volume of the cell increases.

JP 2010-43881 A JP 2005-129414 A

  By the way, in order to protect the dielectric layer from the outside, it is preferable to enclose the dielectric layer in a bag-like cover member. However, when a capacitive sensor is used in this state, deformation of the dielectric layer is likely to be hindered.

  First, when a load is applied to the capacitive sensor, that is, the dielectric layer, excess air is generated from the cell as the volume of the cell is reduced. For this reason, it is necessary to let air escape from the cell. However, if the cover member is sealed, air cannot escape to the outside of the cover member. For this reason, it is difficult for air to escape from the cell. Therefore, the cell is not easily crushed. Therefore, compression of the dielectric layer may be hindered.

  Next, when the load applied to the capacitive sensor, that is, the dielectric layer is removed, the air in the cell becomes insufficient as the volume of the cell increases. For this reason, the cell needs to suck in air. However, if the cover member is sealed, air cannot be taken from the outside of the cover member. For this reason, it is difficult for the cell to suck air. Therefore, the cell is difficult to swell. Therefore, the expansion of the dielectric layer may be hindered.

  In particular, when the dielectric layer expands, that is, when the dielectric layer is restored to its original shape, the dielectric layer is deformed by its own elastic restoring force regardless of the external load. For this reason, if the cell is difficult to inhale air, the restoration speed of the dielectric layer may be significantly reduced.

  In this regard, [FIG. 7] of Patent Document 2 discloses a load sensor having vent holes at two corners on a diagonal line. The load sensor includes two upper and lower elastic plates and a cushion material. Printed wirings are arranged on the lower surface of the upper elastic plate and the upper surface of the lower elastic plate so as to face each other in the vertical direction. The cushion material is interposed between the upper and lower elastic plates. The cushion material is disposed at the peripheral and central portions of the upper and lower elastic plates so as not to interfere with the printed wiring when viewed from above or below. The cushion material arrange | positioned at the peripheral part is arrange | positioned at edge shape along the four sides of two elastic plates on the upper and lower sides. The vent hole is disposed in a gap between the cushion materials adjacent to each other with the corner portion interposed therebetween.

  When a load is applied to the load sensor described in the same document, the pair of upper and lower printed wirings are in contact with each other while the cushion material is compressed. For this reason, a pair of upper and lower printed wirings are conducted. Using the continuity, the load sensor detects that a load has been applied. As described above, the load sensor described in the document is an on-off sensor that detects “a load has been applied”.

  The load sensor described in this document is not a capacitive sensor. However, if the vent hole of the load sensor can be diverted to the capacitance type sensor, the outside of the cover member and the dielectric layer can be communicated with each other through the vent hole. For this reason, the deformation of the dielectric layer is hardly inhibited.

  Specifically, if the cover member is constituted by two elastic base materials, the two base materials are bonded to each other via a double-sided tape, and a ventilation hole is secured in a gap between adjacent double-sided tapes. The outside of the cover member can communicate with the dielectric layer. For this reason, the deformation of the dielectric layer is hardly inhibited.

  However, in this case, a large difference occurs in the tear resistance of the cover member between the portion of the cover member where the double-sided tape is attached and the portion where it is not attached. For example, a capacitive sensor includes a connector for connecting to a control device. Of the cover member, the load tends to concentrate near the base of the connector. For this reason, tears are likely to occur. Moreover, a tear is easy to progress.

  In addition, the capacitive sensor can detect not only “a load has been applied” but also “a load value itself”. In order to increase the detection sensitivity, the thickness of the cover member of the capacitive sensor is often relatively thin. Therefore, the cover member is inherently low in tear resistance.

  As described above, when the double-sided tape is used for the capacitance type sensor, the cover member that is inherently low in tear resistance has a tear resistance between a portion where the double-sided tape is attached and a portion where the double-sided tape is not attached. There will be a large difference in sex. For this reason, it becomes easier to generate a tear. In addition, the tear is more likely to progress.

  The capacitive sensor of the present invention has been completed in view of the above problems. An object of the present invention is to provide a capacitance type sensor in which deformation of a dielectric layer is hardly hindered and a tear is not easily developed in a cover member.

  (1) In order to solve the above-mentioned problem, a capacitive sensor of the present invention is made of a foam and elastically expandable in the front and back directions, and a front side base disposed on the front side of the dielectric layer A cover member having a material and a back side substrate disposed on the back side of the dielectric layer, and inside the periphery of the outer peripheral edge of the cover member that is susceptible to tearing and around the dielectric layer when viewed from the front side or the back side A front side adhesive layer that is disposed and interposed between the front side base material and the back side base material and is adhered to the back surface of the front side base material; a back side adhesive layer that is adhered to the surface of the back side base material; A double-sided adhesive member having a front-side adhesive layer and a core material layer interposed between the back-side adhesive layer and a pair of adjacent circumferential end portions of the double-sided adhesive member that are partitioned between the front and back sides. A through hole for securing a gas passage for the dielectric layer in the intersecting direction. And features.

  The dielectric layer of the capacitive sensor of the present invention is interposed between the front side substrate and the back side substrate. The dielectric layer is surrounded by a double-sided adhesive member. A through hole extending in the crossing direction is defined between a pair of adjacent circumferential end portions of the double-sided adhesive member.

  The capacitance type sensor of the present invention is provided with a through hole that communicates the inside and outside of the cover member. For this reason, even when the dielectric layer is accommodated in the cover member, when the dielectric layer shrinks, the foam cells (voids) are crushed so as to secure an exhaust passage exhausted from the dielectric layer. can do. In addition, when the dielectric layer expands, the foam cell expands, so that a passage for intake air sucked into the dielectric layer can be secured. As described above, according to the capacitive sensor of the present invention, the deformation of the dielectric layer is hardly inhibited.

  Moreover, the double-sided adhesive member includes a core material layer. For this reason, even if it is a case where a front side base material and a back side base material seem to closely_contact | adhere by static electricity etc., the front-back direction length of a through-hole can be ensured.

  The through hole extends in the crossing direction. For this reason, even when another member is laminated on the front side of the front side base material or the back side of the back side base material, the possibility that the through hole is blocked is small. In addition, as compared with the case where the through hole is formed in the front side substrate or the back side substrate, the front side base material or the back side base material is less likely to have a tear starting from the through hole. In addition, the tear is difficult to progress.

  Further, when viewed from the front side or the back side, the double-sided adhesive member is disposed inside the portion of the outer edge of the cover member where the tear is likely to enter. For this reason, it is possible for the double-sided adhesive member to prevent the tear generated in the cover member from progressing inward. Therefore, the cover member can be reinforced.

  (2) Preferably, in the configuration of (1), when viewed from the front side or the back side, the outer edge of the cover member has a corner portion sandwiched between two adjacent sides, and the double-sided adhesive member is It is better to have a configuration that is arranged inside the corner portion exceeding 180 °. Cracks are likely to occur at corners where the included angle exceeds 180 °. Moreover, when a tear occurs, the load tends to concentrate. For this reason, a tear is easy to advance inside. According to this configuration, the double-sided adhesive member can prevent the tear from progressing inward. For this reason, a cover member can be reinforced.

  (3) Preferably, in the configuration of (1) or (2) above, the outer edge of the cover member has a corner portion sandwiched between two adjacent sides when viewed from the front side or the back side, It is better to have a configuration that is arranged inside the corner portion having an included angle of less than 180 °.

  For example, tears are unlikely to occur at corners with a included angle of less than 180 °, such as the apex of a polygon. For this reason, according to this structure, a through-hole can be arrange | positioned inside the corner | angular part which a tear is hard to generate | occur | produce among the outer edges of a cover member.

  (4) Preferably, in any one of the constitutions (1) to (3), the core layer is preferably made of a woven fabric or a non-woven fabric. Woven and non-woven fabrics are difficult to tear. That is, a tear is hard to occur. In addition, the tear is difficult to progress. That is, the tear resistance is high. For this reason, according to this structure, the tear resistance of a core material layer becomes high. Accordingly, the double-sided adhesive member can suppress the development of the tear generated in the cover member.

  (5) Preferably, in any one of the configurations (1) to (4), the cover member is made of an elastomer. Elastomers are flexible and difficult to regulate the deformation of the dielectric layer. Moreover, it is easy to transmit a load to the dielectric layer. For this reason, an elastomer is suitable as a material for the cover member that covers the dielectric layer. However, elastomers are easily torn. That is, a tear is likely to occur. Moreover, a tear is easy to progress. That is, the tear resistance is low.

  In this regard, according to the present configuration, the dielectric layer can be covered with the cover member made of elastomer which is difficult to regulate the deformation of the dielectric layer and easily transmits the load to the dielectric layer. Moreover, the low tear resistance which is the fault of the said cover member can be supplemented with a double-sided adhesive member.

  According to the present invention, it is possible to provide a capacitance type sensor in which the deformation of the dielectric layer is hardly hindered and the tear is not easily developed in the cover member.

1 is a perspective view of a capacitive sensor according to an embodiment of the present invention. It is a perspective exploded view of the same capacitive sensor. It is an upper surface penetration figure of the same capacitance type sensor. FIG. 4 is a cross-sectional view in the IV-IV direction of FIG. 3. It is an enlarged view in the circle V of FIG. FIG. 4 is an enlarged view in a circle VI in FIG. 3. FIG. 4 is an enlarged view in a circle VII in FIG. 3. (A) is an enlarged view in the frame VIII of FIG. FIG. 5B is an enlarged view in the frame VIII of FIG. 4 when a load is applied. It is an enlarged view of the corner | angular part of the electrostatic capacitance type sensor of other embodiment.

  Hereinafter, embodiments of the capacitive sensor of the present invention will be described.

[Configuration of capacitive sensor]
First, the configuration of the capacitive sensor of this embodiment will be described. In the subsequent drawings, the vertical direction corresponds to the “front and back direction” of the present invention. The horizontal direction (front / rear / left / right direction) corresponds to the “cross direction” of the present invention.

  FIG. 1 is a perspective view of the capacitive sensor of the present embodiment. FIG. 2 is an exploded perspective view of the capacitance type sensor. FIG. 3 shows a top transparent view of the same capacitive sensor. FIG. 4 shows a cross-sectional view in the IV-IV direction of FIG. In FIG. 1, the double-sided adhesive members 80 to 87 and the dielectric layer 2 are indicated by alternate long and short dashed lines. Further, in FIG. 2, the front side base material 30 is shown through. Also, the front side wirings 01x to 16x and the back side wirings 01y to 16y are omitted. In FIG. 3, the detection units A0101 to A1616 and the double-sided adhesive members 80 to 87 are hatched.

  As shown in FIGS. 1 to 4, the capacitive sensor 1 of the present embodiment includes a dielectric layer 2, front side electrodes 01 </ b> X to 16 </ b> X, back side electrodes 01 </ b> Y to 16 </ b> Y, front side wirings 01 x to 16 x, and back side wirings. 01y to 16y, cover member 3, front side wiring connector 5, back side wiring connector 6, control device 7, double-sided adhesive members 80 to 87, and through holes 90 to 94 are provided. In addition, in the symbols “AOOΔΔ” of detection units A0101 to A1616 described later, the upper two digits “OO” correspond to the front electrodes 01X to 16X. The last two digits “ΔΔ” correspond to the back-side electrodes 01Y to 16Y.

  The dielectric layer 2 is made of urethane foam and has a rectangular plate shape. Urethane foam is included in the concept of “foam” of the present invention. The dielectric layer 2 includes a large number of cells (holes).

  The cover member 3 includes a front side base material 30 and a back side base material 31. The front-side base material 30 is made of silicone rubber and has a rectangular plate shape. Silicone rubber is included in the “elastomer” concept of the present invention. The front side base material 30 is laminated on the upper side (front side) of the dielectric layer 2. The back side base material 31 is made of silicone rubber and has a rectangular plate shape. The back side base material 31 is laminated below the dielectric layer 2 (back side). The front-side base material 30 and the back-side base material 31 are bonded together in a bag shape by double-sided adhesive members 80 to 87 described later. The dielectric layer 2 is accommodated in the bag. The top four corners of the dielectric layer 2 are spot-bonded to the bottom four corners of the front substrate 30. Further, the lower four corners of the dielectric layer 2 are spot-bonded to the upper four corners of the back-side base material 31. Thus, the dielectric layer 2 is positioned on the front side base material 30 and the back side base material 31 so as not to be wrinkled during use. However, the dielectric layer 2 can be elastically deformed in the horizontal direction with respect to the front-side base material 30 and the back-side base material 31 with the four corners adhered.

  A total of 16 front side electrodes 01 </ b> X to 16 </ b> X are arranged on the lower surface of the front side base material 30. The front-side electrodes 01X to 16X are each formed including acrylic rubber and conductive carbon black. The front side electrodes 01X to 16X each have a strip shape. The front side electrodes 01X to 16X each extend in the left-right direction. The front-side electrodes 01X to 16X are arranged in the front-rear direction so as to be substantially parallel to each other with a predetermined interval.

  A total of 16 front side wirings 01x to 16x are arranged on the lower surface of the front side base material 30. The front-side wirings 01x to 16x are each formed including acrylic rubber and silver powder. The front side wirings 01x to 16x each have a linear shape. The front side wiring connector 5 is disposed at the center of the left side of the front side base material 30. The front side wirings 01x to 16x connect the left ends of the front side electrodes 01X to 16X and the front side wiring connector 5, respectively.

  A total of 16 back-side electrodes 01Y to 16Y are arranged on the upper surface of the back-side base material 31. The back-side electrodes 01Y to 16Y are each formed including acrylic rubber and conductive carbon black. The back side electrodes 01Y to 16Y each have a strip shape. The back-side electrodes 01Y to 16Y each extend in the front-rear direction. The back-side electrodes 01Y to 16Y are arranged in the left-right direction so as to be substantially parallel to each other with a predetermined interval. Thus, the front-side electrodes 01X to 16X and the back-side electrodes 01Y to 16Y are arranged in a lattice shape orthogonal to each other when viewed from above or below.

  A total of 16 back-side wirings 01y to 16y are arranged on the upper surface of the back-side base material 31. Each of the back side wirings 01y to 16y is formed to include acrylic rubber and silver powder. The back side wirings 01y to 16y each have a linear shape. The back side wiring connector 6 is disposed at the left front corner of the back side base material 31. The back side wirings 01y to 16y connect the front ends of the back side electrodes 01Y to 16Y and the back side wiring connector 6, respectively.

  As shown by hatching in FIG. 3, the detection units A0101 to A1616 are arranged at portions (overlapping portions) where the front side electrodes 01X to 16X and the back side electrodes 01Y to 16Y intersect in the vertical direction. Each of the detection units A0101 to A1616 includes a part of the front-side electrodes 01X to 16X, a part of the back-side electrodes 01Y to 16Y, and a part of the dielectric layer 2. A total of 256 (= 16 × 16) detectors A0101 to A1616 are arranged. The detectors A0101 to A1616 are arranged uniformly over substantially the entire surface of the dielectric layer 2.

  The double-sided adhesive members 80 to 87 have a strip shape as shown by hatching in FIG. A total of eight double-sided adhesive members 80 to 87 are arranged along the outer edge of the cover member 3 in a border shape. When viewed from above or below, the dielectric layer 2 is accommodated in the frame of the double-sided adhesive members 80-87.

  The configuration of the double-sided adhesive members 80 to 87 is the same. Hereinafter, the structure of the double-sided adhesive member 83 will be described on behalf of the double-sided adhesive members 80 to 87. FIG. 5 shows an enlarged view in the circle V of FIG. As shown in FIG. 5, the double-sided adhesive member 83 includes a front side adhesive layer 830, a back side adhesive layer 831, and a core material layer 832. The front side adhesive layer 830 is a silicone adhesive. The front side adhesive layer 830 is affixed to the lower surface of the front side base material 30. The back side adhesive layer 831 is a silicone pressure-sensitive adhesive. The back side adhesive layer 831 is attached to the upper surface of the back side base material 31. The core material layer 832 is made of woven fabric, and is interposed between the front side adhesive layer 830 and the back side adhesive layer 831. Returning to FIG. 3, the front-side base material 30 and the back-side base material 31 are bonded together in a bag shape by the eight double-sided adhesive members 80 to 87.

  FIG. 6 shows an enlarged view in the circle VI of FIG. As shown in FIG. 6, a corner portion 330 is disposed on the outer edge 33 of the cover member 3 so as to be sandwiched between two adjacent sides. The included angle θ1 of the corner portion 330 is 270 ° (> 180 °). As viewed from above or below, the double-sided adhesive member 80 is disposed inside the corner portion 330. The double-sided adhesive member 85 is juxtaposed inside the double-sided adhesive member 80.

  As shown in FIG. 3, the through holes 90 to 94 are arranged at the corners of the cover member 3, the attachment portions of the front-side wiring connector 5, and the attachment portions of the back-side wiring connector 6. Specifically, the through hole 90 is disposed between the double-sided adhesive member 80 and the double-sided adhesive member 81 that are adjacent in the circumferential direction. The through hole 91 is disposed between the double-sided adhesive member 81 and the double-sided adhesive member 82 that are adjacent in the circumferential direction. The through hole 92 is disposed between the double-sided adhesive member 82 and the double-sided adhesive member 83 that are adjacent in the circumferential direction. The through hole 93 is disposed between the double-sided adhesive member 83 and the double-sided adhesive member 84 that are adjacent in the circumferential direction. The through hole 94 is disposed between the double-sided adhesive member 84 and the double-sided adhesive member 80 that are adjacent in the circumferential direction. The through holes 90 to 94 all extend in the horizontal direction. Moreover, all of the through holes 90 to 94 communicate with the inside and outside of the cover member 3.

  The configuration of the through holes 90 to 94 is the same. Hereinafter, the configuration of the through hole 90 will be described on behalf of the through holes 90 to 94. FIG. 7 shows an enlarged view in a circle VII in FIG. As shown in FIG. 7, a corner portion 331 is disposed on the outer edge 33 of the cover member 3 so as to be sandwiched between two adjacent sides. The included angle θ2 of the corner portion 331 is 90 ° (<180 °). When viewed from above or below, the through hole 90 is disposed inside the corner portion 331. That is, the through-hole 90 is arranged using a gap 900 between the rear end (circumferential end) 800 of the double-sided adhesive member 80 and the left end (circumferential end) 810 of the double-sided adhesive member 81. Has been.

  The hole length L1 of the through hole 90 is set by the front-rear direction width of the double-sided adhesive member 81. The opening width L2 of the through hole 90 is set by the width in the left-right direction of the gap 900 (the distance between the adjacent double-sided adhesive member 80 and double-sided adhesive member 81). The opening thickness of the through hole 90 is set by the vertical thickness (mainly the vertical thickness of the core material layer 832) L3 of the double-sided adhesive member 83 shown in FIG.

  As shown in FIGS. 1 and 3, the control device 7 is electrically connected to the front-side wiring connector 5 and the back-side wiring connector 6 via the wirings 100 and 101. The control device 7 includes a storage unit 70 and a calculation unit 71. The storage unit 70 stores a table indicating the correspondence between the capacitances of the detection units A0101 to A1616 and the load, a correction amount for the ambient temperature, and the like. Further, the storage unit 70 temporarily stores impedance and phase input from the front-side wiring connector 5 and the back-side wiring connector 6. The calculation unit 71 calculates the capacitances of the detection units A0101 to A1616 based on the impedance and phase. And the load added to detection part A0101-A1616 from an electrostatic capacitance is detected.

[Capacitive sensor movement]
Next, the movement of the capacitive sensor 1 of this embodiment will be briefly described. The capacitance of the capacitor, which is the principle of load detection of the capacitance type sensor 1, is calculated from the following equation (1).
C = ε · S / d Formula (1)
In the formula (1), C is a capacitance, ε is a dielectric constant, S is an overlapping area of opposing electrodes, and d is a distance between electrodes. The interelectrode distance d corresponds to the thickness of the dielectric layer 2 in the vertical direction. The overlapping area S corresponds to the area of the detection units A0101 to A1616 indicated by hatching in FIG. 3, that is, the overlapping area of the front side electrodes 01X to 16X and the back side electrodes 01Y to 16Y.

  FIG. 8A shows an enlarged view in the frame VIII of FIG. FIG. 8B shows an enlarged view in the frame VIII of FIG. 4 when a load is applied. As shown in FIG. 8B, when a load F is applied to an arbitrary detection unit A1416 from above, the dielectric layer 2 is compressed in the vertical direction. For this reason, the vertical thickness of the dielectric layer 2 is reduced. Here, the vertical thickness of the dielectric layer 2 corresponds to the inter-electrode distance d in Expression (1). Therefore, as the vertical thickness of the dielectric layer 2 decreases, the capacitance C increases accordingly. The control device 7 illustrated in FIG. 3 calculates a load applied to an arbitrary detection unit A1416 based on the change in the capacitance C. When the load F is removed from the detection unit A1416, the dielectric layer 2 is restored to the original shape shown in FIG. 8A by its own elastic restoring force.

[Functions of through holes 90 to 94]
Next, the function of the through holes 90 to 94 when the capacitive sensor 1 of the present embodiment moves will be described. As schematically shown in FIG. 8A, a large number of cells 20 are formed in the dielectric layer 2. Air accumulates inside the cell 20.

  As shown in FIG. 8B, when a load F is applied to the detection unit A1416 from above, the dielectric layer 2 is compressed in the vertical direction. For this reason, many cells 20 are crushed up and down. Here, when many cells 20 are crushed, the air in the cells 20 is discharged to the outside of the dielectric layer 2. As indicated by white arrows in FIG. 7, the discharged air is exhausted to the outside of the cover member 3 through the through holes 90 to 94. For this reason, the dielectric layer 2 is quickly compressed by the load F.

  When the load F is removed from the detection unit A1416, the dielectric layer 2 expands in the vertical direction by its own elastic restoring force. For this reason, many cells 20 extend in the vertical direction. Here, when a large number of cells 20 are expanded, air is sucked into the cells 20. As indicated by white arrows in FIG. 7, the sucked air is taken from the outside of the cover member 3 through the through holes 90 to 94. For this reason, the dielectric layer 2 is rapidly expanded by an elastic restoring force. Then, the original shape shown in FIG.

[Functions of double-sided adhesive members 80 and 85 inside corner portion 330]
Next, functions of the double-sided adhesive members 80 and 85 disposed inside the corner portion 330 shown in FIG. 6 will be described. As shown in FIG. 1, the wiring 100 for the control device 7 is connected to the front-side wiring connector 5. For this reason, the mounting portion 34 of the front-side wiring connector 5 in the cover member 3 is likely to be subjected to a torsional load in the front → left → rear direction and in the opposite direction (lateral direction) as indicated by the white arrow Y1. Further, as indicated by the white arrow Y2, a torsional load is likely to be applied in the front → upper → rear direction and the opposite direction (vertical direction). Further, these torsional loads tend to concentrate on the corner portions 330 and 332 at the base of the mounting portion 34 of the front-side wiring connector 5.

  Here, the cover member 3 is made of silicone rubber. For this reason, tear resistance is low. Therefore, as shown in FIG. 6, the crevice c is likely to be generated inward from the corner portion 330. Moreover, the crevice c tends to progress inward.

  In this regard, double-sided adhesive members 80 and 85 are disposed inside the corner portion 330. Here, as shown in FIG. 5, the core material layer 832 of the double-sided adhesive members 80 and 85 is made of woven fabric. For this reason, tear resistance is high. Therefore, the progress of the tear c can be stopped by the double-sided adhesive members 80 and 85.

  In addition, the corner | angular part 332 of the attachment part 34 of the connector 5 for front side wiring shown in FIG. 1 and the corner | angular part 333 of the attachment part 35 of the connector 6 for back side wiring 6 are also the same as the corner | angular part 330 shown in FIG. The tear c is likely to occur. For this reason, the double-sided adhesive members 84 and 87 inside the corner portion 332 and the double-sided adhesive members 84 and 86 inside the corner portion 333 also have the same functions as the double-sided adhesive members 80 and 85.

[Function and effect]
Next, the function and effect of the capacitive sensor 1 of the present embodiment will be described. According to the capacitive sensor 1 of the present embodiment, as shown in FIGS. 2, 7, 8 (a), and 8 (b), the dielectric layer 2 is accommodated in the cover member 3. The through holes 90 to 94 can secure a gas passage when the dielectric layer 2 expands and contracts. For this reason, deformation of the dielectric layer 2 is not easily inhibited. Therefore, the dielectric layer 2 can be quickly deformed when the load F is applied and when the load F is removed.

  Further, as shown in FIG. 5, the double-sided adhesive members 80 to 87 include a core material layer 832. For this reason, even if it is a case where the front side base material 30 and the back side base material 31 closely_contact | adhere, for example by static electricity etc., the opening thickness (front-back direction) of the through-holes 90-94 by the up-down direction thickness L3 of the double-sided adhesive member 83. Length) can be secured.

  As shown in FIG. 7, the through holes 90 to 94 extend in the horizontal direction. For this reason, even when another member is laminated on the upper surface of the front-side base material 30 and the lower surface of the back-side base material 31, there is little possibility that the openings outside the through holes 90 to 94 are blocked. Further, as compared with the case where the through holes 90 to 94 are formed in the front-side base material 30 and the back-side base material 31, the tear c is less likely to occur in the front-side base material 30 and the back-side base material 31. Moreover, the crevice c is hard to progress.

  As shown in FIG. 1 and FIG. 6, the double-sided adhesive members 80, 84, 85 to 87 are arranged inside the portion of the outer edge 33 of the cover member 3 where the tear c is likely to enter when viewed from above or below. Has been. Specifically, it is arrange | positioned inside the corner | angular part 330, 332, 333 where the included angle (theta) 1 exceeds 180 degrees. For this reason, it is possible for the double-sided adhesive members 80, 84, 85 to 87 to prevent the tear c from progressing inward. Therefore, the cover member 3 can be reinforced. Further, disconnection of the front-side wirings 01x to 16x and the back-side wirings 01y to 16y can be suppressed.

  Further, as shown in FIG. 1, the double-sided adhesive members 80 and 85 are arranged in an inner and outer double with respect to the corner portion 330. Similarly, the double-sided adhesive members 84 and 87 are arranged in an inner and outer double with respect to the corner portion 332. Similarly, the double-sided adhesive members 84 and 86 are arranged in an inner and outer double with respect to the corner portion 333. For this reason, it can prevent reliably that the crevice c progresses inside.

  Moreover, as shown in FIG. 5, the core material layer 832 is made of woven fabric. For this reason, tear resistance is high. Therefore, according to the capacitive sensor 1 of this embodiment, the tear resistance of the core material layer 832, that is, the double-sided adhesive members 80 to 87 is increased.

  In the double-sided adhesive members 80 to 87, the direction in which the tear resistance is high is the extending direction of the double-sided adhesive members 80 to 87. In this regard, according to the capacitive sensor 1 of the present embodiment, as shown in FIG. 6, the double-sided adhesive members 80 and 85 are extended so that the extending direction of the double-sided adhesive members 80 and 85 is substantially orthogonal to the progress direction of the tear c. Adhesive members 80 and 85 are arranged. For this reason, it can prevent strongly that the crevice c progresses inside.

  Moreover, as shown in FIG. 1, when viewed from above or below, the through holes 90 to 94 are disposed inside the corners having an included angle of less than 180 °. For example, as shown in FIG. 7, the through hole 90 is disposed inside the corner portion 331 having the included angle θ2 of less than 180 °. The crevice c is less likely to occur at the corners where the included angle is less than 180 °. As described above, according to the capacitive sensor 1 of the present embodiment, the through hole 90 to the inside of the corner portion of the outer edge 33 of the cover member 3 where the tear c is unlikely to occur and the included angle is less than 180 °. 94 can be arranged.

  Moreover, when performing the affixing operation | work of two sides which pinch | interpose a corner | angular part among the outer edges 33 of the cover member 3 with the straight strip | belt-shaped double-sided adhesive members 80-87, if one single-sided double-sided adhesive member 80-87 is used, Therefore, it is necessary to bend the double-sided adhesive members 80 to 87 along the two sides. For this reason, the pasting operation is difficult. On the other hand, when the two double-sided adhesive members 80 to 87 are used, the double-sided adhesive members 80 to 87 may be arranged one by one with respect to the two sides. For this reason, the pasting work is easy. Therefore, a gap 900 between the double-sided adhesive members 80 to 87 is likely to appear at the corner (for example, the corner 331 shown in FIG. 7). In this regard, according to the capacitive sensor 1 of the present embodiment, the through holes 90 to 94 can be arranged using the gap 900. For this reason, the operation of attaching the double-sided adhesive members 80 to 87 and the operation of arranging the through holes 90 to 94 can be easily performed.

  Further, as shown in FIG. 2, the through holes 90 to 94 are arranged so as to surround the detection units A0101 to A1616. For this reason, as shown in FIG. 8, the air intake / exhaust effect with respect to the cell 20 can be uniformly exhibited with respect to all the detection parts A0101-A1616. For this reason, the deformation speed of the dielectric layer 2 is unlikely to vary between the detection units A0101 to A1616.

  The cover member 3 is made of silicone rubber. For this reason, the cover member 3 is flexible and it is difficult to restrict the deformation of the dielectric layer 2. Further, it is easy to transmit the load F to the dielectric layer 2. Thus, silicone rubber is suitable as a material for the cover member 3 that covers the dielectric layer 2. However, silicone rubber has low tear resistance. In addition, in order to improve the sensitivity of the capacitive sensor 1, the thicknesses in the vertical direction of the front-side base material 30 and the back-side base material 31 are steadily decreasing. Due to these factors, the tear resistance of the cover member 3 is very low.

  In this regard, according to the capacitive sensor 1 of the present embodiment, the dielectric layer 2 is covered with the cover member 3 made of silicone rubber, which is difficult to regulate the deformation of the dielectric layer 2 and easily transmits the load F to the dielectric layer 2. Can do. Moreover, the low tear resistance which is the fault of the cover member 3 can be supplemented by the double-sided adhesive members 80 to 87.

  Moreover, the dielectric layer 2 of the capacitive sensor 1 of the present embodiment is made of urethane foam. For this reason, when the load F is input, the dielectric layer 2 is less likely to bulge in the horizontal direction as it is compressed and deformed in the vertical direction. That is, since the urethane foam cells (holes) consume the bulging portion, although the density of the dielectric layer 2 is increased, it is difficult to bulge in the horizontal direction. Therefore, the deformation of the dielectric layer 2 is not easily regulated by the front-side base material 30 and the back-side base material 31 stacked on the dielectric layer 2 in the vertical direction.

  In the detection units A0101 to A1616, the dielectric layer 2 is not fixed to the front side electrodes 01X to 16X and the back side electrodes 01Y to 16Y. Also in this respect, the deformation of the dielectric layer 2 is not easily regulated by the front side base material 30 and the back side base material 31. In addition, the directionality is less likely to appear in the load detection characteristics of the capacitive sensor 1. That is, even if the capacitive sensor 1 is disposed upside down, the load detection characteristics do not change.

  Further, according to the capacitive sensor 1 of the present embodiment, the dielectric layer 2 is bonded to the front side base material 30 and the back side base material 31 at the four corners. For this reason, the dielectric layer 2 is less likely to be wrinkled during use.

[Others]
The embodiment of the capacitive sensor of the present invention has been described above. However, the embodiment is not particularly limited to the above embodiment. Various modifications and improvements that can be made by those skilled in the art are also possible.

  For example, in the above embodiment, the front electrodes 01X to 16X and the front wirings 01x to 16x are arranged on the lower surface of the front substrate 30. In addition, the back-side electrodes 01Y to 16Y and the back-side wirings 01y to 16y are arranged on the upper surface of the back-side base material 31. However, you may arrange | position an electrode and wiring, and a base material separately. Further, the electrode and the wiring may be disposed outside the cover member 3.

  Moreover, in the said embodiment, although the front side wiring connector 5 and the back side wiring connector 6 were arrange | positioned, the front side wiring connector 5 and the back side wiring connector 6 do not need to be arrange | positioned. That is, instead of the front-side wiring connector 5 and the back-side wiring connector 6, an extraction part for the front-side wirings 01x to 16x and an extraction part for the back-side wirings 01y to 16y may be arranged. The gas entering and exiting the cell 20 of the dielectric layer 2 may be other than air. For example, nitrogen, carbon dioxide, hydrogen, oxygen, inert gas, and the like may be used.

  The material of the dielectric layer 2 is not particularly limited. Any foam may be used. For example, elastomer foams such as silicone rubber, acrylonitrile-butadiene copolymer rubber, acrylic rubber, epichlorohydrin rubber, chlorosulfonated polyethylene, chlorinated polyethylene, urethane rubber, natural rubber, isoprene rubber may be used. . Also, a resin foam such as polyurethane, polystyrene, polyolefin (polyethylene, polypropylene, etc.), phenol resin, polyvinyl chloride, urea resin, silicone, polyimide, melamine resin may be used.

  Moreover, the manufacturing method of a foam is not specifically limited. For example, a foam is a slab product (a foam obtained by producing a continuous foam by flowing a stock solution on a driving conveyor and continuously foaming, and then cutting the continuous into a predetermined length). Alternatively, it may be a molded product (a foam obtained by injecting a stock solution into a mold and foaming it, and then removing it from the mold). Moreover, the cell (bubble) of a foam may be a closed cell type or an open cell type.

  In the case of the capacitive sensor 1 of the above embodiment, the front side electrodes 01X to 16X, the front side wirings 01x to 16x, the back side electrodes 01Y to 16Y, and the back side wirings 01y to 16y are formed including an elastomer. In this case, since these electrodes and wires expand and contract, there is an advantage that they can be deformed integrally with the dielectric layer 2. These electrodes and wiring may be made of metal. Further, it may be made of a material obtained by performing metal plating on the surface of the organic fiber.

  In addition, the number, shape (electrode width, length, etc.) and arrangement (interval between adjacent electrodes, crossing angle between front electrode and back electrode, etc.) of front side electrodes 01X-16X and back side electrodes 01Y-16Y are particularly limited. do not do.

  Moreover, in the said embodiment, although the input direction of the load F with respect to the capacitive sensor 1 was made into the up-down direction, the input direction of the load F is not specifically limited. It may be a left-right direction, a front-rear direction, or a direction inclined with respect to these directions. Further, the arrangement direction of the capacitive sensor 1 is not limited to the horizontal direction. The direction may be a vertical direction or a direction inclined with respect to the horizontal direction and the vertical direction.

  Moreover, the material of the double-sided adhesive members 80-87, a dimension, the number of arrangement | positioning, and an arrangement place are not specifically limited. For example, in the above-described embodiment, as shown in FIG. 6, the direction in which the tear c easily develops and the extending direction of the double-sided adhesive members 80 to 87 are substantially orthogonal. However, the direction in which the tear c easily develops and the extending direction of the double-sided adhesive members 80 to 87 may intersect at an angle other than orthogonal.

  Moreover, in the said embodiment, as shown in FIG. 1, the double-sided adhesive members 80 and 85 were arrange | positioned with respect to the corner | angular part 330 inside and outside. Similarly, the double-sided adhesive members 84 and 87 are arranged inside and outside the corner 332. Similarly, the double-sided adhesive members 84 and 86 are arranged inside and outside the corner 333. However, the double-sided adhesive members 80 to 87 may be arranged in a single layer. If it carries out like this, the arrangement | positioning number of the double-sided adhesive members 80-87 will decrease. Moreover, you may arrange | position the double-sided adhesive members 80-87 more than the inside / outside double with respect to the cover member 3 in the perimeter. If it carries out like this, the cover member 3 can be reinforced more strongly.

  Moreover, you may surround the circumference | surroundings of the dielectric layer 2 in the end ring shape by the single double-sided adhesive members 80-87. And you may arrange | position the single through-holes 90-94 between the circumferential direction both ends (C-shaped both ends) of the single-sided adhesive members 80-87.

  Moreover, when arrange | positioning the double-sided adhesive members 80-87 inside and outside double, the inside double-sided adhesive members 85-87 and the outside double-sided adhesive members 80-84 may be different types. That is, as shown in FIG. 1 and FIG. 2, the outer double-sided adhesive members 80 to 84 that are annularly connected and the inner double-sided adhesive members 85 to 87 that are arranged in spots are different types. Good. The reason is that, in the case of the double-sided adhesive members 80 to 84 on the outside, the main purpose of the arrangement is to bond the front side base material 30 and the back side base material 31 and to secure the open state of the through holes 90 to 94. That's why. On the other hand, in the case of the inner side double-sided adhesive members 85 to 87, the reinforcement of the corners 330, 332, and 333 is the main purpose of the arrangement.

  In the above embodiment, the reinforcing double-sided adhesive member 85 is attached to the base corners 330 and 332 of the attachment portion 34 of the front-side wiring connector 5 and the base corner portion 333 of the attachment portion 35 of the back-side wiring connector 6. ~ 87 was placed. However, even if the reinforcing double-sided adhesive members 85 to 87 are arranged at the corners of the base of all the protruding portions that protrude in the horizontal direction (the surface development direction of the cover member 3) of the outer edge 33 of the cover member 3. Good.

  In FIG. 9, the enlarged view of the corner | angular part of the capacitive sensor of other embodiment is shown. In addition, about the site | part corresponding to FIG. 7, it shows with the same code | symbol. As shown in FIG. 9, a double-sided adhesive member 88 may be disposed inside the through hole 90 when viewed from above or below. If it carries out like this, it can suppress that the crevice c progresses through the through-hole 90. FIG.

  Moreover, as shown in FIG. 5, although the material of the front side adhesive layer 830, the back side adhesive layer 831, and the core material layer 832 is not particularly limited, the core material layer 832 is made of nonwoven fabric, elastomer, resin, or foam. Is preferred. In particular, glass cloth is preferable from the viewpoint of tear resistance. The double-sided adhesive members 80 to 87 only need to ensure a gap (= vertical thickness L3) between the front-side base material 30 and the back-side base material 31 in a state where the load F is not applied. That is, it is only necessary to ensure the open state of the through holes 90 to 94. As the double-sided adhesive members 80 to 87, for example, a commercially available double-sided tape such as a glass cloth double-sided tape (manufactured by Teraoka Seisakusho) may be used.

  The dimensions, the number of arrangement, and the arrangement location of the through holes 90 to 94 are not particularly limited. When the cover member 3 has a polygonal shape, it may be arranged near the apex. For example, if the cover member 3 has a quadrangular shape, it may be arranged at four corners. If it carries out like this, the through-holes 90-94 can be arrange | positioned in the part which is hard to concentrate a load among the cover members 3. FIG.

  As shown in FIG. 7, the hole length L <b> 1 of the through hole 90 may be adjusted by the front-rear direction width of the double-sided adhesive member 81. The opening width L2 of the through hole 90 may be adjusted by the width in the left-right direction of the gap 900 (the interval between the adjacent double-sided adhesive member 80 and double-sided adhesive member 81). The opening thickness of the through hole 90 may be adjusted by the vertical thickness (mainly the vertical thickness of the core material layer 832) L3 of the double-sided adhesive member 83 shown in FIG.

  The material of the front side base material 30 and the back side base material 31 is not specifically limited. Elastomers (for example, thermosetting elastomers such as natural rubber and synthetic rubber, thermoplastic elastomers such as TPU (thermoplastic polyurethane) and SBS (polystyrene, polybutadiene, polystyrene alloy elastomer)), PET (polyethylene terephthalate), PP (polypropylene) , PE (polyethylene), PVC (polyvinyl chloride), PA (polyamide) and the like. These organic materials generally have low tear resistance. For this reason, it is suitable for reinforcing with the double-sided adhesive members 80 to 87.

1: Capacitance type sensor, 2: dielectric layer, 3: cover member, 5: front side wiring connector, 6: back side wiring connector, 7: control device.
01X to 16X: Front side electrode, 01Y to 16Y: Back side electrode, 01x to 16x: Front side wiring, 01y to 16y: Back side wiring.
20: Cell, 30: Front side base material, 31: Back side base material, 33: Outer edge, 34: Attachment part, 35: Attachment part, 70: Storage part, 71: Calculation part, 80-88: Double-sided adhesive member, 90- 94: Through hole.
θ1: included angle, θ2: included angle, 100: wiring, 101: wiring, 330 to 333: corner, 800: rear end (circumferential end), 810: left end (circumferential end), 830: Front side adhesive layer, 831: back side adhesive layer, 832: core material layer, 900: gap.
A0101-A1616: detection part, c: tear.

Claims (5)

A dielectric layer made of foam and elastically stretchable in the front and back direction;
A cover member having a front side substrate disposed on the front side of the dielectric layer and a back side substrate disposed on the back side of the dielectric layer;
The outer side of the cover member as viewed from the front side or the back side is disposed on the inside of the portion where the tear is likely to enter and around the dielectric layer, and is interposed between the front side base material and the back side base material, and the front side base material A double-sided adhesive layer comprising: a front-side adhesive layer that is adhered to the back surface of the substrate; a back-side adhesive layer that is adhered to the surface of the back-side base material; and a core material layer that is interposed between the front-side adhesive layer and the back-side adhesive layer. Members,
A through-hole that is partitioned between a pair of adjacent circumferential end portions of the double-sided adhesive member and secures a gas passage for the dielectric layer in a crossing direction intersecting the front and back direction;
A capacitive sensor comprising: When viewed from the front side or the back side, the outer edge of the cover member has a corner portion sandwiched between two adjacent sides,
The capacitive sensor according to claim 1, wherein the double-sided adhesive member is disposed inside the corner portion having an included angle exceeding 180 °. When viewed from the front side or the back side, the outer edge of the cover member has a corner portion sandwiched between two adjacent sides,
The capacitive sensor according to claim 1, wherein the through hole is disposed inside the corner portion having an included angle of less than 180 °.   The capacitive sensor according to any one of claims 1 to 3, wherein the core layer is made of a woven fabric or a non-woven fabric.   The capacitive sensor according to claim 1, wherein the cover member is made of an elastomer.

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