WO2007138829A1

WO2007138829A1 - Capacitive sensor

Info

Publication number: WO2007138829A1
Application number: PCT/JP2007/059671
Authority: WO
Inventors: Yasushi Shimomoto; Daisuke Kuzuyama; Satoshi Nozoe; Masao Hashimoto; Kazunobu Itonaga
Original assignee: Omron Corporation; Omron Healthcare Co., Ltd.
Priority date: 2006-05-25
Filing date: 2007-05-10
Publication date: 2007-12-06
Also published as: JP2007315921A

Abstract

A spacer (4) consists of an adhesive sheet (8) bonded to a movable electrode side substrate (2) and a fixed electrode side substrate (3), a gap stabilization member (7) not bonded to at least one of the movable electrode side substrate (2) and the fixed electrode side substrate (3), or a gap stabilization member (7) bonded to at least one of the movable electrode side substrate (2) and the fixed electrode side substrate (3) with adhesive strength weaker than that acting between the movable electrode side substrate (2) and the fixed electrode side substrate (3). The adhesive sheet (8) is at least not arranged at a position closer to the movable electrode side substrate (2) or the fixed electrode side substrate (3) between spacers (4) than the gap stabilization member (7). A flexible capacitive sensor exhibiting excellent response and hysteresis characteristics is thereby provided.

Description

Specification

Capacitive sensor

Technical field

The present invention relates to a capacitance type sensor that detects a physical quantity based on a change in capacitance between electrodes facing each other with a gap therebetween.

Background art

Conventionally, a capacitance type sensor that detects a change in physical quantity by a change in capacitance is known. Capacitance sensors can be used for various sensors such as pressure sensors, acceleration sensors, and vibration detection sensors. In addition, the capacitance type sensor has an advantage that the temperature characteristic is more stable than the piezo type sensor using a piezoresistive element or the like. In addition, since capacitive semiconductor sensors using silicon semiconductor substrates can be manufactured using IC manufacturing technology, they are highly uniform, and can be easily reduced in size and weight and integrated with circuits. Has the advantage of being. Furthermore, since the capacitive semiconductor sensor using the silicon semiconductor substrate can be mass-produced by a large-scale batch method, it has an advantage that low cost can be realized. From the above, the capacitance type sensor is generally widely used.

[0003] A capacitive sensor is a sensor that utilizes the fact that the capacitance (the amount of electricity to be charged) of two electrodes facing each other changes depending on the distance separating the electrodes. Convert and detect.

[0004] As shown in Patent Document 1: Japanese Patent Laid-Open Publication No. 2005-337774 (published December 8, 2005), a general electrostatic capacitance sensor is provided on a substrate. A movable electrode provided on another substrate is arranged above the fixed electrode so as to face each other. A spacer is provided between the substrate having the fixed electrode and the substrate having the movable electrode so that the fixed electrode and the movable electrode face each other with a gap therebetween.

[0005] In addition, when flexibility is required for the capacitance type sensor, the spacer having flexibility is divided into a substrate having a fixed electrode and a substrate having a movable electrode by an elastic adhesive member. Adhesion is a little different. [0006] However, the adhesive member generally has viscosity and elasticity, and has a viscous component in which a stress proportional to the deflection rate of the substrate acts and an elastic component in which a stress proportional to the deflection amount of the substrate acts. There is also power. Since the viscosity component of the adhesive member has time dependency as described above, the greater the viscosity component of the adhesive member, the more the response to pressure is delayed due to the influence of viscosity.

[0007] Since a flexible adhesive member has a low crosslinking density, the viscosity component inevitably increases due to the molecular structure, and is greatly affected by the viscosity. Therefore, when the above-mentioned conventional adhesive member is used for the spacer of a capacitive sensor that requires flexibility, the response to the pressure applied to the capacitive sensor is delayed, and the response of the sensor This will cause problems such as deterioration in performance and hysteresis characteristics.

Disclosure of the invention

The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide a capacitive sensor that has flexibility and is excellent in responsiveness and hysteresis characteristics. is there.

[0009] In order to solve the above-described problem, the capacitive sensor of the present invention includes a first substrate on which a first electrode is provided, and a second substrate on which a second electrode is provided. And the first electrode and the second electrode are arranged to face each other, and the first electrode and the second electrode are provided with a gap between the first electrode and the second electrode. A flexible spacer is provided so that at least one of the first electrode or the second electrode is sandwiched between the substrate and the second substrate. As for the capacitive sensor, the spacer includes an adhesive member bonded to the first substrate and the second substrate, and at least the first substrate or the second substrate. It consists of a gap holding member that is bonded to one side of the substrate and sandwiched between the above spacers! / At least closer to the gap holding member than the first electrode or the second electrode! The above-mentioned adhesive member is disposed at a position, and is characterized by the above.

[0010] According to the above invention, the gap holding member and at least one of the first substrate and the second substrate are not bonded. In other words, even if a physical quantity in the stacking direction is applied to the first substrate or the second substrate, the region where the gap holding member is disposed. In the region, it is possible to suppress the influence of the viscosity caused by the adhesion to be smaller than when the adhesion is made to both the first substrate and the second substrate.

[0011] Furthermore, an adhesive member is disposed at a position at least near the gap holding member with respect to the first electrode or the second electrode sandwiched between the flexible spacers. As described above, in the area around the first electrode or the second electrode sandwiched between the spacers, which is an area for actually detecting the physical quantity applied to the first board or the second board. Thus, the influence of viscosity can be kept small. As a result, the influence of viscosity can be minimized with a flexible capacitive sensor as described above. Therefore, the response and hysteresis characteristics of a flexible capacitive sensor can be reduced. Improvements can be made. As a result, it is possible to realize a capacitance type sensor that has flexibility and is excellent in response and hysteresis characteristics.

[0012] Further, in order to solve the above problems, the capacitive sensor of the present invention provides a first substrate provided with a first electrode and a second substrate provided with a second electrode. The first electrode and the second electrode are arranged to face each other, and the first electrode and the second electrode are provided with a gap between the first electrode and the second electrode. A flexible spacer is provided so that at least one of the first electrode and the second electrode is sandwiched between the substrate and the second substrate. In the capacitive sensor having the above, the spacer includes an adhesive member bonded to the first substrate and the second substrate, and at least the first substrate or the second substrate. Adhering to the first substrate and the second substrate and the adhesive member to one of the substrates The gap holding member is bonded with a weaker adhesive force than the first electrode or the second electrode sandwiched between the spacers. The adhesive member is disposed at a position nearer to the member.

[0013] According to the above invention, the gap holding member and at least one of the first substrate and the second substrate act on adhesion between the first substrate, the second substrate, and the adhesive member. It is configured to be bonded with an adhesive strength weaker than the adhesive strength. Here, when the adhesive force is weakened, the viscosity component is generally reduced. Therefore, even if a physical quantity in the stacking direction is applied to the first substrate or the second substrate, the gap holding member is disposed. In such a region, it is possible to suppress the influence of the viscosity caused by the adhesion to be smaller than when the adhesion is made to both the first substrate and the second substrate.

[0014] Furthermore, an adhesive member is disposed at a position at least near the gap holding member with respect to the first electrode or the second electrode sandwiched between the flexible spacers. As described above, in the area around the first electrode or the second electrode sandwiched between the spacers, which is an area for actually detecting the physical quantity applied to the first board or the second board. Thus, the influence of viscosity can be kept small. As a result, the influence of viscosity can be minimized with a flexible capacitive sensor as described above. Therefore, the response and hysteresis characteristics of a flexible capacitive sensor can be reduced. Improvements can be made. As a result, it is possible to realize a capacitance type sensor that has flexibility and is excellent in response and hysteresis characteristics.

Brief Description of Drawings

FIG. 1 is a schematic view showing one embodiment of a capacitance type sensor according to the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of the capacitive sensor.

[FIG. 3] (a) is a graph showing the pressure responsiveness of a conventional capacitive sensor, and (b) is a graph showing the pressure-capacitance characteristics of a conventional capacitive sensor. .

[FIG. 4] (a) is a graph showing the pressure responsiveness of the capacitance type sensor according to the present invention, and (b) is a graph showing the pressure capacitance characteristic of the capacitance type sensor according to the present invention. It is.

FIG. 5 is a graph showing the loss elastic modulus, storage elastic modulus and loss tangent of polyimide.

FIG. 6 is a graph showing the loss modulus, storage modulus and loss tangent of polyester resin.

FIG. 7 (a) is a schematic view showing another embodiment of the capacitive sensor according to the present invention, and FIG. 7 (b) shows another embodiment of the capacitive sensor according to the present invention. FIG.

[FIG. 8] (a) is a schematic diagram showing still another embodiment of the capacitive sensor of the present invention, and (b) is still another embodiment of the capacitive sensor of the present invention. It is the schematic which shows the form of. [FIG. 9] (a) is a schematic diagram showing still another embodiment of the capacitive sensor of the present invention, and (b) is still another embodiment of the capacitive sensor of the present invention. It is the schematic which shows the form of.

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4B. In the following embodiments, the drawings are simplified or modified as appropriate, and the dimensions and shapes of the respective parts are not necessarily drawn accurately.

FIG. 1 is a diagram showing a schematic configuration of the capacitive sensor 1 according to the present embodiment. FIG. 2 is a cross-sectional view of the Β · Β cut surface of the capacitive sensor 1 in FIG. FIG. First, an outline of the configuration of the capacitive sensor 1 will be described with reference to FIGS. 1 and 2.

The capacitive sensor 1 in the present embodiment is a flexible capacitive sensor, and includes a movable electrode side substrate (first substrate) 2 and a fixed electrode side substrate (second 3) Spacer 4 consisting of a gear stabilizing member (gap retaining member) 7 and an adhesive sheet (adhesive member) 8, a movable electrode (first electrode) 5, and a fixed electrode (second electrode) It has six.

[0019] On the surface of the movable electrode side substrate 2, the movable electrode 5 is formed by a thick film or thin film technique or the like, and the movable electrode 5 is provided in an array. The movable electrode side substrate 2 is made of, for example, a conductive semiconductor silicon substrate, a polyimide film, a PET film, or an epoxy resin film.

[0020] Further, on the surface of the fixed electrode side substrate 3, the fixed electrode 6 is formed by a thick film or thin film technique or the like, and the fixed electrode 6 is provided in an array as shown in FIG. . The fixed electrode side substrate 3 is made of, for example, an insulating glass substrate, a polyimide film, a PET film, or an epoxy resin film.

As will be described in detail later, the spacer 4 holds the gap (space) between the movable electrode side substrate 2 and the fixed electrode side substrate 3 so that the movable electrode 5 and the fixed electrode 6 The gap between the two is maintained. The size of the gap is arbitrarily set according to the width of the physical quantity to be detected by the capacitive sensor 1 and the deformation amount of the movable electrode side substrate 2. The

The spacer 4 is composed of a gap stabilizing member 7 and an adhesive sheet 8. Since the capacitive sensor 1 is a flexible capacitive sensor, the spacer 4 is also composed of a flexible gap stabilizing member 7 and an adhesive sheet 8.

The movable electrode 5 also has, for example, Au, Cu, AL, or Ag, and is formed on the surface of the movable electrode side substrate 2 as described above. Similarly, the fixed electrode 6 is made of, for example, Au, Cu, AL, or Ag, and is formed on the surface of the fixed electrode side substrate 3 as described above. In addition, the movable electrode 5 and the fixed electrode 6 are formed with substantially the same thickness.

[0023] In the present embodiment, description of other configurations generally provided in a capacitive sensor such as a wiring connected to movable electrode 5 and fixed electrode 6 is omitted. .

Next, the arrangement of the members of the capacitive sensor 1 will be described with reference to FIG.

As shown in FIG. 1, the members are arranged in the order of the movable electrode side substrate 2, the movable electrode 5, the fixed electrode 6, and the fixed electrode side substrate 3, and the movable electrode side substrate 2 is A spacer 4 as a support portion is disposed above the fixed electrode side substrate 3 with a gap. The movable electrode side substrate 2 is disposed with a gap above the fixed electrode side substrate 3, so that the movable electrode 5 and the fixed electrode side substrate formed on the surface of the movable electrode side substrate 2 are disposed. 3 is arranged to face the fixed electrode 6 formed on the surface of 3 with a force gap.

Next, a method for detecting the physical quantity applied to the surface of the movable electrode side substrate 2 by the capacitive sensor 1 will be described.

First, when a physical quantity such as pressure is applied to the surface of the movable electrode side substrate 2 in the direction A in FIG. 1, the movable electrode side substrate 2 bends according to the applied pressure. Subsequently, the position of the movable electrode 5 approaches the fixed electrode 6 by the amount of deflection of the movable electrode side substrate 2. Then, a change in the capacitance between the movable electrode 5 and the fixed electrode 6 occurs due to a change in the distance between the movable electrode 5 and the fixed electrode 6. Therefore, if the change in capacitance is detected, the movable electrode side substrate 2 The physical quantity applied to the surface of the can be detected.

[0028] Subsequently, characteristic portions of the capacitive sensor 1 of the present embodiment will be described.

In the capacitance type sensor 1 according to the present embodiment, the spacer 4 is composed of the gap stabilizing collar member 7 and the adhesive sheet 8 as described above. As shown in FIGS. 1 and 2, the gap stabilizing member 7 is configured so that the movable electrode 5 and the fixed electrode 6 are sandwiched between the movable electrode side substrate 2 and the fixed electrode side substrate 3, respectively. They are arranged in parallel. The gap stabilizing member 7 has the same flexibility as that of the movable electrode side substrate 2 and has the same compressive strength as the movable electrode side substrate 2. Specifically, the gap stabilizing member 7 is made of, for example, polyimide, PET film, or epoxy film.

In addition, as shown in FIGS. 1 and 2, the adhesive sheet 8 has a gap stabilizing structure in which the movable electrode 5 and the fixed electrode 6 are sandwiched between the movable electrode side substrate 2 and the fixed electrode side substrate 3. The members 7 are arranged in parallel so as to sandwich the member 7 therebetween. The adhesive sheet 8 also has, for example, polyester resin, epoxy resin, polyurethane resin, or silicon resin.

As described above, the positional relationship between the gap stabilizing member 7 and the adhesive sheet 8 overlaps with each other in the vertical direction (the direction in which the movable electrode side substrate 2 and the fixed electrode side substrate 3 are stacked). The rectangular parallelepiped is arranged in parallel so that there is no. Further, the positional relationship between the gap stabilizing member 7 and the adhesive sheet 8 is such that at least the gap stabilizing member 7 is disposed between the movable electrode 5 and the fixed electrode 6 and the adhesive sheet 8. It is summer. The gap stabilizing member 7 is bonded (fixed) only in the horizontal direction (direction orthogonal to the direction in which the movable electrode side substrate 2 and the fixed electrode side substrate 3 are laminated) by the adhesive sheet 8. The adhesive sheet 8 is fixed to both the movable electrode side substrate 2 and the fixed electrode side substrate 3, but the gap stabilizing member 7 is at least the movable electrode side substrate 2 or the fixed electrode side substrate 3. The force is fixed to one side, or is not fixed to both the movable electrode side substrate 2 and the fixed electrode side substrate 3. As the fixing method, for example, a method of integrally forming the movable electrode side substrate 2 or the fixed electrode side substrate 3 can be used. Further, as the above-mentioned integral molding method, the movable electrode side substrate 2 or the fixed electrode side substrate 3 and the gap stabilizing member 7 are simultaneously molded, or insert molding or outsert molding. Further, as the fixing method, at least the movable electrode side substrate 2 or the fixed power source is used. This is achieved by using thermocompression bonding in which one of the pole side substrate 3 and the gap stabilizing member 7 is melted and bonded with heat.

In this embodiment, when the arrangement directions of the movable electrode 5 and the fixed electrode 6 are the same direction, the gap stabilizing member 7 sandwiches the movable electrode 5 and the fixed electrode 6. Forces that indicate the arrangement of the arrangements Not necessarily limited to this. For example, when the arrangement directions of the movable electrode 5 and the fixed electrode 6 are orthogonal to each other, the gap stabilizing member 7 is arranged so as to sandwich either the movable electrode 5 or the fixed electrode 6. It may be.

[0033] In the capacitive sensor 1 of the present invention, the spacer 4 includes an adhesive sheet 8 bonded to the movable electrode side substrate 2 and the fixed electrode side substrate 3, and at least the movable electrode side substrate 2. Alternatively, the gap stabilizing member 7 is bonded to one of the fixed electrode side substrate 3 and the adhesive sheet 8 and the gap stabilizing member 7 are connected to the movable electrode side substrate 2 and the fixed electrode. The movable electrode side substrate 2 and the fixed electrode side substrate 3 sandwiched between the spacers 4 are arranged so that they do not overlap with each other in the stacking direction with the side substrate 3. The adhesive sheet 8 is not disposed at least at a position closer to the gap stabilizing member 7, and the adhesive sheet 8 and the gap stabilizing member 7 are bonded only in the direction orthogonal to the stacking direction. ing.

According to the above configuration, the gap stabilizing member 7 and at least one of the movable electrode side substrate 2 or the fixed electrode side substrate 3 are not bonded, and the adhesive sheet 8 and the gap stabilizing member 7 Are arranged so that they overlap each other in the stacking direction of the movable electrode side substrate 2 and the fixed electrode side substrate 3, and the adhesive sheet 8 and the gap stabilizing member 7 are arranged in the stacking direction. In other words, it is bonded only in the orthogonal direction. That is, even if pressure in the stacking direction is applied to the movable electrode side substrate 2 or the fixed electrode side substrate 3, in the region where the gap stabilizing member 7 is disposed, the movable electrode side substrate 2 and the fixed electrode It is possible to suppress the influence of the viscosity caused by the adhesion to be smaller than when the adhesion is made to both of the side substrates 3.

[0035] Furthermore, an adhesive sheet 8 is disposed at least closer to the gap stabilizing member 7 with respect to the movable electrode 5 or the fixed electrode 6 sandwiched between the flexible spacers 4. Therefore, the gap around the movable electrode 5 or the fixed electrode 6 sandwiched between the spacers 4 is an area where the pressure applied to the movable electrode side substrate 2 or the fixed electrode side substrate 3 is actually detected. The influence of viscosity can be kept small in the region where the eaves member 7 is disposed. Therefore, the influence of the viscosity can be suppressed to a small extent by the flexible capacitive sensor 1, so that the response and hysteresis characteristics of the flexible capacitive sensor 1 can be improved. It can be carried out. As a result, it is possible to realize a capacitive sensor 1 that has flexibility and is excellent in responsiveness and hysteresis characteristics.

[0036] Next, the actual effect when the electrostatic capacitance sensor 1 of the present invention is used will be described with reference to FIGS. Fig. 3 (a) is a graph showing the pressure response of a conventional capacitive sensor, and Fig. 3 (b) is a graph showing the hysteresis characteristics of a conventional capacitive sensor. 4 (a) is a graph showing the pressure response of the capacitive sensor 1 according to the present invention, and FIG. 4 (b) shows the hysteresis characteristic of the capacitive sensor 1 according to the present invention. It is a graph. FIG. 5 is a graph showing the loss elastic modulus, storage elastic modulus and loss tangent of polyimide, and FIG. 6 is a graph showing the loss elastic modulus, storage elastic modulus and loss tangent of polyester resin. Here, the loss modulus represents the viscous component of the material, and the storage modulus represents the elastic component of the material. That is, in general, the reaction force generated when a material is bent has an elastic component and a viscous component. Of these, the elastic component shows the degree of reaction force proportional to the amount of deflection of the material and has no time dependence. On the other hand, the viscosity component indicates the degree of reaction force proportional to the deflection speed of the material, and has a time dependency, which causes a delay in response in a capacitive sensor. In the capacitance type sensor 1 used in the measurement of FIGS. 4 (a) and 4 (b), polyimide is used for the material of the movable electrode side substrate 2, polyimide is used for the material of the fixed electrode side substrate 3, and the movable electrode. Au is used for the material 5, Au is used for the material of the fixed electrode 6, polyimide is used for the material of the gap stabilization member 7, and polyester resin is used for the material of the adhesive sheet 8.

[0037] First, the difference in pressure response between the conventional capacitive sensor and the capacitive sensor 1 of the present invention will be described. In (a) of Fig. 3 and (a) of Fig. 4, the solid line represents the pressure value stored on the sensor, and the dotted line represents the sensor output value for this applied pressure. As shown in Fig. 3 (a) and Fig. 4 (a), the sensor output is compared to the input pressure graph value. The values of the graph in FIG. 6 are closer to the actual input pressure value than the value detected using the conventional capacitive sensor of the value detected using the capacitive sensor 1 of the present invention. Yes. That is, the capacitive sensor 1 of the present invention has a higher pressure response than the conventional capacitive sensor.

[0038] Next, the difference in hysteresis characteristics between the conventional capacitive sensor and the capacitive sensor 1 of the present invention will be described. In (b) and (b) of Fig. 3, the solid line indicates the capacitance value of the sensor when the pressure value applied to the sensor increases, and the dotted line indicates that the pressure value stored in the sensor decreases. It represents the capacitance value of the sensor as it goes. Note that C in (b) in Fig. 3 and (b) in Fig. 4 represents capacitance, and P represents pressure. Comparing (b) in Fig. 3 with (b) in Fig. 4, the capacitance value of the graph when the pressure increases and the capacitance value of the graph when the pressure decreases When the difference is detected using the capacitance type sensor 1 of the present invention, the difference is smaller than when detected using the conventional capacitance type sensor. Since the difference between the capacitance value when the pressure increases and the capacitance value when the pressure decreases corresponds to hysteresis, the direction of the capacitance sensor 1 of the present invention is the conventional capacitance. Hysteresis is smaller than that of the sensor, and the hysteresis characteristics are improved.

[0039] As described above, the capacitive sensor 1 of the present invention has actually improved pressure responsiveness and hysteresis characteristics as compared with the conventional capacitive sensor.

In the capacitive sensor 1 of the present invention, it is preferable that the gap stabilizing member 7 has the same material force as the movable electrode side substrate 2 and the fixed electrode side substrate 3.

[0041] As a result, the gap stabilizing member 7 has the same flexibility and compressive strength as the movable electrode side substrate 2 and the fixed electrode side substrate 3, so that the capacitive sensor 1 is bent. Thus, even when pressure is applied to the capacitive sensor 1, the structure of the capacitive sensor 1 can be kept stable.

Furthermore, in the capacitance type sensor 1 of the present invention, the gap stabilizing member 7 has a storage elastic modulus as an index indicating the influence of viscosity between the movable electrode side substrate 2 and the fixed electrode side substrate 3. When the loss tangent value, which is the ratio of the loss elastic modulus, is the same, the material force has a loss tangent value less than or equal to the loss tangent value of the movable electrode side substrate 2 and the fixed electrode side substrate 3. Yes, if the loss tangent values of movable electrode side substrate 2 and fixed electrode side substrate 3 are not the same. It is preferable that the movable electrode side substrate 2 or the fixed electrode side substrate 3 is made of a material having a loss tangent value equal to or smaller than the loss tangent value of the substrate having the larger loss tangent value.

Accordingly, a material having a loss tangent value of at least the movable electrode side substrate 2 or the fixed electrode side substrate 3 is used as the gap stabilizing member 7. Since at least the movable electrode side substrate 2 and the fixed electrode side substrate 3 themselves do not have a larger adhesive force than the adhesive sheet 8, the loss tangent value of the movable electrode side substrate 2 and the fixed electrode side substrate 3 itself is at least the adhesive Smaller than 8th. In other words, according to the above configuration, the gap stabilizing member 7 has a loss tangent value smaller than the loss tangent of the adhesive sheet 8. Therefore, response delay, hysteresis, and aging can be improved as compared with the case where only the adhesive sheet 8 is used.

Furthermore, in the capacitance type sensor 1 of the present invention, the gap stabilization member 7 has a loss tangent value that is a value of a ratio between a storage elastic modulus and a loss elastic modulus as an index indicating the influence of viscosity. However, it is preferably made of a material smaller than the loss tangent value of the movable electrode side substrate 2 and the fixed electrode side substrate 3. Specifically, when a polyimide having a loss tangent tan δ value of 0.01-0.03 is used as the material of the movable electrode side substrate 2 and the fixed electrode side substrate 3, It is preferable to use a material having a value equal to or less than the loss tangent for the gap stabilization flange.

Thus, a material whose loss tangent is at least smaller than that of the movable electrode side substrate 2 or the fixed electrode side substrate 3 is used as the gap stabilizing member 7. That is, according to the above configuration, the gap stabilizing member 7 has a loss tangent value smaller than the loss tangent of the adhesive sheet 8. Accordingly, response delay, hysteresis, and change with time can be improved as compared with the case where only the adhesive sheet 8 is used.

This will be described with reference to FIGS. 5 and 6. FIG. 5 shows the loss elastic modulus, storage elastic modulus, and loss tangent of polyimide, which is a material used for the movable electrode side substrate 2, the fixed electrode side substrate 3, and the gap stabilizing member 7 in this embodiment. ing. FIG. 6 shows the loss elastic modulus, storage elastic modulus, and loss tangent of polyester resin, which is a material used for the adhesive sheet 8 in the present embodiment. In FIGS. 5 and 6, E ′ represents the storage elastic modulus, E ′ ′ represents the loss elastic modulus, and tan δ represents the loss tangent (loss coefficient). The loss is positive The contact tan δ is related to tan S = Ε, ΖΕ.

[0047] As shown in Fig. 5, the storage elastic modulus Ε of polyimide is 4000 to 4300 MPa, the loss elastic modulus E is 43 to 128 MPa, and the loss tangent tan δ is 0.01 to 0.03! / Speak. As shown in Fig. 6, the storage modulus 榭 of polyester resin is 14.5 to 309 MPa, loss modulus E is 21.6 to 124, and loss tangent tan δ is 0.4 to 1. It has become 5. As described above, the loss tangent of the material used for the movable electrode side substrate 2 and the fixed electrode side substrate 3 is much smaller than the material used for the adhesive member such as the adhesive sheet 8.

[0048] Further, in the capacitive sensor 1 of the present invention, an elongated hole (slit) is provided in the region of the movable electrode side substrate 2 between the individual movable electrodes 5 arranged in an array. I like it.

Thus, even when the capacitive sensor 1 is bent in the direction in which the slits are arranged, the slits are provided between the movable electrodes 5, so that the deformation of the movable electrode side substrate 2 can be prevented. Thus, each movable electrode 5 can be independent. Therefore, the surface of the movable electrode 5 can be made more parallel to the bent surface, and the decrease in sensitivity that occurs when the capacitive sensor 1 is bent can be suppressed. In addition, since it is separated from other adjacent movable electrode 5 by a slit, structural crosstalk can be reduced.

[0050] Furthermore, in the capacitance type sensor 1 of the present invention, a capacitance plate is provided by stiffening the fixed electrode 6 by installing a reinforcing plate on the back surface of the fixed electrode 6 on the fixed electrode side substrate 3. It is preferable that the bending at the time of bending of the sensor 1 is concentrated in the region between the fixed electrodes 6.

[0051] This makes it possible to maintain the flatness of the fixed electrode 6, so that the relationship between the surface of the movable electrode 5 and the surface of the fixed electrode 6 on the bent surface can be made more parallel. Thus, it is possible to further suppress the decrease in sensitivity that occurs when the capacitive sensor 1 is bent.

In the present embodiment, the capacitance type sensor 1 has a configuration in which a plurality of movable electrodes 5 and fixed electrodes 6 are provided in an array, but the present invention is not necessarily limited thereto. For example, the capacitive sensor 1 may be configured to include a pair of the movable electrode 5 and the fixed electrode 6.

In the present embodiment, the gap stabilizing member 7 is bonded to at least one of the movable electrode side substrate 2 and the fixed electrode side substrate 3, but it is always configured. Is not limited to this. For example, at least the movable electrode side substrate 2 or the fixed electrode side substrate 3 On the other hand, the gap stabilizing member 7 is supplementarily bonded. In this case, the auxiliary adhesion is weaker than the adhesive force that acts on the adhesion between the movable electrode side substrate 2 and the fixed electrode side substrate 3 and the adhesive sheet 8, and means adhesion with adhesive force. The

According to the above configuration, the gap stabilizing member 7 and at least one of the movable electrode side substrate 2 or the fixed electrode side substrate 3 are bonded to the movable electrode side substrate 2 and the fixed electrode side substrate 3. It is configured to be bonded with an adhesive force weaker than the adhesive force acting on the adhesive. Here, when the adhesive force is weakened, the viscosity component is generally reduced. Therefore, even if a physical quantity in the stacking direction is applied to the movable electrode side substrate 2 or the fixed electrode side substrate 3, the movable electrode side substrate 2 and the fixed electrode are not formed in the region where the gap stabilizing member 7 is disposed. It is possible to suppress the influence of the viscosity caused by the adhesion to be smaller than when the adhesion is made to both of the side substrates 3.

[Second Embodiment]

Another embodiment of the present invention will be described below with reference to FIGS. 7 (a) to 8 (b). The configuration other than that described in the present embodiment is the same as that of the first embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of the first embodiment are given the same reference numerals and explanations thereof are omitted. Further, in the following embodiments, the drawings are appropriately simplified or modified, and the dimensions and shapes of the respective parts are not necessarily drawn accurately.

[0056] The capacitive sensor 11 and the capacitive sensor 21 of the present embodiment are different from the capacitive sensor 1 of the first embodiment in that the gap stabilizing member 7 and the adhesive The shape of Route 8 is different.

First, the shapes of the gap stabilizing member 7 and the adhesive sheet 8 of the capacitive sensor 11 in the present embodiment will be described with reference to FIGS. 7 (a) and 7 (b). . FIG. 7 (a) is a diagram showing a schematic configuration of the capacitive sensor 11 in the present embodiment, and FIG. 8 (b) is a diagram of the capacitive sensor 11 in FIG. 7 (a). It is a cross-sectional view of the C′C cut surface with the A direction force.

In the capacitive sensor 11 according to the present embodiment, the surfaces of the gap stabilizing member 7 and the adhesive sheet 8 that are in contact with each other are comb-shaped as shown in FIG. 7 (b). That is, multiple The gap stabilizing member 7 and the adhesive sheet 8 are fitted to each other. Then, as shown in FIGS. 7 (a) and 7 (b), the adhesive sheet 8 is not disposed at a position closer to the movable electrode 5 and the fixed electrode 6 than the gap stabilizing member 7. Become a composition!

[0059] The positional relationship between the gap stabilizing member 7 and the adhesive sheet 8 is the same as in the case of the capacitive sensor 1, and the vertical direction (the movable electrode side substrate 2 and the fixed electrode side substrate 3 are separated from each other). They are arranged so that they do not overlap in the direction of lamination. The gap stabilizing member 7 is bonded (fixed) only in the horizontal direction (direction orthogonal to the direction in which the movable electrode side substrate 2 and the fixed electrode side substrate 3 are laminated) by the adhesive sheet 8. The adhesive sheet 8 is fixed to both the movable electrode side substrate 2 and the fixed electrode side substrate 3, but the gap stabilizing member 7 is at least the movable electrode side substrate 2 or the fixed electrode side. It is fixed to one of the substrates 3 or is not fixed to both the movable electrode side substrate 2 and the fixed electrode side substrate 3.

[0060] According to the above configuration, the area of the adhesive surface between the gap stabilizing member 7 and the adhesive sheet 8 is the case where the gap stabilizing member 7 and the adhesive sheet 8 are arranged in parallel. It is wider than the area of the adhesive surface. Therefore, the gap stabilizing member 7 can be more strongly bonded to the adhesive sheet 8. As a result, the structure of the capacitive sensor 11 can be kept more stable.

[0061] In the present embodiment, the configuration in which each of the surfaces of the gap stabilizing member 7 and the adhesive sheet 8 that are in contact with each other is formed of a plurality of uneven portions is shown. Not exclusively. For example, the configuration may be such that one is a concave portion and the other is a convex portion, each of which has a single concave portion or convex portion. However, since the area of the adhesive surface between the gap stabilizing member 7 and the adhesive sheet 8 is wider when the shape is composed of a plurality of concave and convex portions, the structure of the capacitive sensor 11 is kept more stable. be able to.

Next, the shape of the gap stabilizing member 7 and the adhesive sheet 8 of the capacitive sensor 21 in the present embodiment will be described with reference to FIG. 8 (a) and FIG. 8 (b). Do. FIG. 8 (a) is a diagram showing a schematic configuration of the capacitive sensor 21 in the present embodiment, and FIG. 8 (b) is a diagram of the capacitive sensor 21 in FIG. 8 (a). Cross section of D'D cut surface with force in A direction FIG.

In the capacitive sensor 21 according to the present embodiment, the gap stabilizing collar member 7 has a shape surrounding the adhesive sheet 8 as shown in FIG. 8B. Then, as shown in FIGS. 8 (a) and 8 (b), the adhesive sheet 8 is not arranged at a position closer to the movable electrode 5 and the fixed electrode 6 than the gear stabilizing member 7 is. It has become.

[0064] As in the case of the capacitance sensor 1, the positional relationship between the gap stabilizing member 7 and the adhesive sheet 8 is the vertical direction (the movable electrode side substrate 2 and the fixed electrode side substrate 3 are They are arranged so that they do not overlap in the direction of lamination. The gap stabilizing member 7 is bonded (fixed) only in the horizontal direction (direction orthogonal to the direction in which the movable electrode side substrate 2 and the fixed electrode side substrate 3 are laminated) by the adhesive sheet 8. The adhesive sheet 8 is fixed to both the movable electrode side substrate 2 and the fixed electrode side substrate 3, but the gap stabilizing member 7 is at least the movable electrode side substrate 2 or the fixed electrode side. It is fixed to one of the substrates 3 or is not fixed to both the movable electrode side substrate 2 and the fixed electrode side substrate 3.

[0065] According to the above configuration, the area of the adhesive surface between the gap stabilizing member 7 and the adhesive sheet 8 is the case where the gap stabilizing member 7 and the adhesive sheet 8 are arranged in parallel. It is wider than the area of the adhesive surface. Therefore, the gap stabilizing member 7 can be more strongly bonded to the adhesive sheet 8. As a result, the structure of the capacitive sensor 21 can be kept more stable.

In the first embodiment and the second embodiment, the gap stabilizing member 7 and the adhesive sheet 8 are arranged in the stacking direction of the movable electrode side substrate 2 and the fixed electrode side substrate 3. A force showing a configuration in which the gap stabilizing member 7 and the adhesive sheet 8 are bonded only in a direction perpendicular to the stacking direction. Not necessarily this. For example, the gap stabilization member 7 and the adhesive sheet 8 may overlap each other in the stacking direction of the movable electrode side substrate 2 and the fixed electrode side substrate 3, or the gap stabilization member 7 and the adhesive sheet 8. May be bonded in a direction other than the direction perpendicular to the stacking direction.

[0067] Specific examples are shown below using (a) in FIG. 9 and (b) in FIG. Figure 9 (a) shows the book FIG. 10 is a diagram showing a schematic configuration of a capacitive sensor 31 in the embodiment, and FIG. 9 (b) is a diagram showing a schematic configuration of a capacitive sensor 41 in the present embodiment.

First, in the capacitive sensor 31 in FIG. 9A, a part of the gap stabilizing member 7 and the adhesive sheet 8 overlap each other in the stacking direction. Further, the adhesive surface between the gap stabilizing member 7 and the adhesive sheet 8 is inclined (inclined) with respect to the stacking direction.

[0069] Also in the capacitive sensor 41 of Fig. 9B, the gap stabilizing member 7 and the adhesive sheet 8 partially overlap each other in the stacking direction. In the capacitive sensor 41, the adhesive surfaces of the gap stabilizing member 7 and the adhesive sheet 8 are bonded so as to exist in the stacking direction and the direction orthogonal to the stacking direction. .

[0070] Even with the above configuration, even if a physical quantity in the stacking direction is applied to the movable electrode side substrate 2 or the fixed electrode side substrate 3, it is possible in the region where the gap stabilizing member 7 is disposed. It is possible to suppress the influence of the viscosity caused by the adhesion to be smaller than when the adhesion is made to both the moving electrode side substrate 2 and the fixed electrode side substrate 3. However, compared with the configuration of the capacitance type sensor 31 and the capacitance type sensor 41, the force of the configuration of the capacitance type sensor 1, the capacitance type sensor 11 and the capacitance type sensor No. 1 The effect of viscosity caused by adhesion when a physical quantity in the stacking direction is applied to this substrate or the second substrate can be suppressed. This is because the configurations of the capacitive sensor 31 and the capacitive sensor 41 are different from those of the capacitive sensor 1, the capacitive sensor 11 and the capacitive sensor. This is because the gap stabilizing portion 7 and the adhesive sheet 8 in the direction are more affected by the viscosity of the adhesive surface.

[0071] According to the present invention, in the region where the gap holding member is disposed, the influence of the viscosity caused by adhesion is suppressed to be smaller than when the gap holding member is adhered to both the first substrate and the second substrate. It becomes possible. Furthermore, since the influence of viscosity can be reduced in the area around the first electrode or the second electrode sandwiched between the flexible spacers, the capacitive sensor having flexibility. Response and hysteresis characteristics can be improved. Therefore, there is an effect that it is possible to provide a capacitive sensor that has flexibility and is excellent in responsiveness and hysteresis characteristics.

[0072] In order to solve the above problems, the electrostatic capacitance sensor of the present invention is provided with a first electrode. The first substrate and the second substrate on which the second electrode is provided, the first electrode and the second electrode are arranged to face each other, and the first electrode In order to provide a gap between the first electrode and the second electrode, at least one of the first electrode and the second electrode is provided between the first substrate and the second substrate. The spacer is provided with a flexible spacer so as to be sandwiched between the first substrate and the second substrate. A gap holding member that is bonded to at least one of the first substrate and the second substrate and is sandwiched between the spacers. At least the gap holding portion with respect to the first electrode or the second electrode. Near than! The above-mentioned adhesive member is disposed at a position, and is characterized by the above.

[0073] Further, in order to solve the above problems, the capacitive sensor of the present invention provides a first substrate provided with a first electrode and a second substrate provided with a second electrode. The first electrode and the second electrode are arranged to face each other, and the first electrode and the second electrode are provided with a gap between the first electrode and the second electrode. A flexible spacer is provided so that at least one of the first electrode and the second electrode is sandwiched between the substrate and the second substrate. In the capacitive sensor having the above, the spacer includes an adhesive member bonded to the first substrate and the second substrate, and at least the first substrate or the second substrate. Adhering to the first substrate and the second substrate and the adhesive member to one of the substrates The gap holding member is bonded with a weaker adhesive force than the first electrode or the second electrode sandwiched between the spacers. The adhesive member is disposed at a position nearer to the member.

[0074] In the capacitive sensor of the present invention, the adhesive member and the gap holding member are arranged so as not to overlap each other in the stacking direction of the first substrate and the second substrate. In addition, it is preferable that the adhesive member and the gap holding member are bonded only in a direction perpendicular to the stacking direction.

Thereby, the adhesive member and the gap holding member are arranged so that they are not overlapped with each other in the stacking direction of the first substrate and the second substrate. Gap retention The member is bonded only in the direction orthogonal to the stacking direction. That is, even if a physical quantity in the stacking direction is applied to the first substrate or the second substrate, the gap holding member and the adhesive member are bonded only in the direction orthogonal to the stacking direction. Therefore, the influence of viscosity can be further reduced.

[0076] Further, in the capacitance type sensor of the present invention, it is preferable that the adhesive member and the stabilizing member are fitted to each other so that the surfaces in contact with each other are uneven. .

Thereby, the area of the adhesive surface between the gap holding member and the adhesive member becomes larger than the area of the adhesive surface in the case where the gap holding member and the adhesive member are arranged in parallel. Therefore, the gap holding member can be more strongly bonded to the adhesive member. That is, the gap holding member can be more firmly fixed in the capacitive sensor. Therefore, the structure of the capacitive sensor can be kept more stable.

In the capacitive sensor of the present invention, it is preferable that the stabilizing member is disposed so as to surround a surface of the adhesive member other than the stacking direction.

[0080] Further, in the capacitance type sensor of the present invention, the gap holding member has a storage elastic modulus and a loss elastic modulus as an index indicating the influence of viscosity between the first substrate and the second substrate. When the loss tangent value, which is the value of the ratio between and, is the same, the material force has a loss tangent value less than or equal to the loss tangent value of the first substrate and the second substrate. If the loss tangent value of the second substrate is not the same as that of the second substrate, at least the loss tangent value of the substrate having the larger loss tangent value of the first substrate or the second substrate. It is preferable that the material force has the following loss tangent value.

Thus, a material having a loss tangent value of at least the first substrate or the second substrate or less is used as the gap holding member. Since at least the first substrate and the second substrate itself do not have a larger adhesive force than the adhesive member, the first substrate and the second substrate itself The value of the loss tangent is at least smaller than that of the adhesive member. That is, according to the above configuration, the gap holding member has a loss tangent value that is smaller than the loss tangent of the adhesive member. Accordingly, response delay, hysteresis, and change with time can be improved as compared with the case where only the adhesive member is used.

In the capacitance type sensor of the present invention, the gap holding member has a loss tangent value that is a value of a ratio between a storage elastic modulus and a loss elastic modulus as an index indicating the influence of viscosity. It is preferable that the material force is smaller than the loss tangent value of the first substrate and the second substrate.

Accordingly, a material whose loss tangent is at least smaller than that of the first substrate or the second substrate is used as the gap holding member. That is, according to the above configuration, the gap holding member has a loss tangent value smaller than the loss tangent of the adhesive member. Accordingly, response delay, hysteresis, and change with time can be improved as compared with the case where only the adhesive member is used.

It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims, and the technical means disclosed in each of the different embodiments is appropriately used. Embodiments obtained by combining are also included in the technical scope of the present invention.

Industrial applicability

[0085] As described above, the capacitive sensor of the present invention has flexibility and is excellent in responsiveness and hysteresis characteristics. Therefore, the present invention can be suitably used in an industrial field related to a capacitive sensor having flexibility.

Claims

The scope of the claims

[1] A first substrate provided with a first electrode and a second substrate provided with a second electrode, wherein the first electrode and the second electrode are opposed to each other. And at least the first electrode or the second substrate between the first substrate and the second substrate in order to provide a gap between the first electrode and the second electrode. In a capacitive sensor that has a flexible spacer provided so as to sandwich one of the second electrodes!

The spacer is bonded to at least one of the first substrate and the second substrate by bonding an adhesive member bonded to the first substrate and the second substrate. In addition, there are gap holding members and capacities,

The adhesive member is disposed at a position closer to the first electrode or the second electrode sandwiched between the spacers than the gap holding member. Capacitance type sensor.

[2] The first electrode is provided, and the first substrate and the second electrode are provided, and the second substrate is provided, and the first electrode and the second electrode are opposed to each other. And at least the first substrate between the first substrate and the second substrate in order to provide a gap between the first electrode and the second electrode. In a capacitive sensor that has a flexible spacer so as to sandwich one of the electrode and the second electrode!

The spacer includes the adhesive member bonded to the first substrate and the second substrate, and the first substrate to at least one of the first substrate and the second substrate. And a gap holding member that is bonded with an adhesive force that is weaker than the adhesive force that acts on the adhesion between the second substrate and the adhesive member,

[3] The adhesive member and the gap holding member are arranged so that they are not overlapped with each other in the stacking direction of the first substrate and the second substrate. Giat 3. The capacitance type sensor according to claim 1, wherein the holding member is bonded only in a direction orthogonal to the upper ra layer direction.

[4] The electrostatic capacitance type sensor according to claim 1 or 2, wherein the adhesive member and the giilS gear-up holding are fitted with each other in contact with each other in an uneven shape.

'Sa.

[5] The static amount sensor according to claim 1 or 2, wherein the gear-up holding member is disposed so as to surround a surface of the adhesive member other than the stacking direction.

[6] The gap retention has a loss tangent value that is a value of a ratio between a storage elastic modulus and a loss elastic modulus as a finger indicating the influence of viscosity between the first ¾S and the second substrate. If they are the same, the first substrate and the second substrate are made of a material having a loss tangent value equal to or less than the loss tangent value, and the loss between the first S¾ and the second substrate If the tangent values are not the same, at least the loss tangent value of the I-th substrate or the second substrate, or the loss tangent value less than or equal to the loss tangent value of the other substrate must be set. The static sensor according to claim 1 or 2, characterized by comprising a material having the same.

[7] The gap holding member has a loss tangent value, which is a power of a ratio between a storage elastic modulus and a loss elastic modulus, which indicates an influence of viscosity, as a sign of the first substrate and the second substrate. The capacitance type sensor according to claim 1 or 2, wherein the sensor is made of a material smaller than a loss tangent value. '.

Corrected paper