JP2021162384A - Sensor unit - Google Patents

Abstract

To provide a sensor unit including a plurality of pressure-sensitive sensors with a simplified wiring structure and improved connection reliability.SOLUTION: For each of laminates 13 and 14 in pressure-sensitive sensors 12A and 12B, a first sensor electrode 21 is connected to a first circuit part electrode 31 and a second sensor electrode 23 is connected to a second circuit part electrode 33. Thus, the pressure-sensitive sensors 12A and 12B are electrically connected to the circuit part 30. The first sensor electrode 21 and the second sensor electrode 23 for each of the laminates 13 and 14 are formed on a substrate 11. A negative electrode layer 16 (second electrode layer) in the laminate 13 closer to the substrate 11 is formed on a surface of a dielectric layer 17 farther from the substrate 11. A member held between the negative electrode layer 16 and the second sensor electrode 23 includes a second conductive structure that is flexible and penetrates a positive electrode layer 15 (first electrode layer) in an insulated state in a thickness direction. The negative electrode layer 16 is connected to the second sensor electrode 23 through the second conductive structure part.SELECTED DRAWING: Figure 3

Description

The present invention relates to a sensor unit that includes a plurality of pressure-sensitive sensors that detect pressure applied from the outside, and performs processing using the detection results of the pressure-sensitive sensors.

A sensor unit in which a flexible pressure-sensitive sensor and a circuit unit that performs processing using the detection result of the pressure-sensitive sensor are arranged on a flexible substrate is known. The pressure-sensitive sensor is configured by laminating a first electrode layer, a dielectric layer, and a second electrode layer in this order on a substrate. The first sensor electrode is connected to the first electrode layer, and the second sensor electrode is connected to the second electrode layer. Both the first sensor electrode and the second sensor electrode are formed on the substrate. The first circuit unit electrode and the second circuit unit electrode connected to the circuit unit, respectively, are also formed on the substrate. In the above sensor unit, the first sensor electrode is connected to the first circuit section electrode, and the second sensor electrode is connected to the second circuit section electrode, whereby an electrical connection to the circuit section of the pressure sensitive sensor is made. There is.

In the above sensor unit, if the second electrode layer separated from the substrate in the thickness direction is connected to the second sensor electrode on the substrate by a wiring portion provided outside the pressure-sensitive sensor, the dielectric layer becomes The wiring portion may move due to expansion and contraction, causing disconnection and the like, which may reduce the connection reliability. In addition, the wiring structure may become complicated. Therefore, the sensor unit is required to improve connection reliability while simplifying the wiring structure.

In addition, Patent Document 1 and Patent Document 2 describe a technique for making an electrical connection through a through hole. Therefore, from the above technique, it is conceivable to provide a through hole in the dielectric layer and connect the second electrode layer and the second sensor electrode through the through hole.

Japanese Unexamined Patent Publication No. 7-209070 Japanese Unexamined Patent Publication No. 2009-77619

The above-mentioned Patent Document 1 and Patent Document 2 are based on the premise that there is a single pressure sensor, but are of a type in which a plurality of pressure sensors are provided and processing is performed using the detection results of the pressure sensors. The sensor unit also has the same problem, and the same effect as described above is required.

The present invention has been made in view of such circumstances, and an object of the present invention is to improve connection reliability while simplifying a wiring structure in a sensor unit including a plurality of pressure-sensitive sensors.

In the sensor unit that solves the above problems, a plurality of flexible pressure-sensitive sensors and a circuit unit that performs processing using the detection results of the plurality of pressure-sensitive sensors are arranged on a flexible substrate. Each pressure-sensitive sensor is provided with at least one laminate in which the dielectric layer is sandwiched between the first electrode layer and the second electrode layer having different polarities in the thickness direction of the substrate, and the first one for each of the laminates. The first sensor electrode is connected to the electrode layer, the second sensor electrode is connected to the second electrode layer, and the first circuit unit electrode and the second circuit unit electrode connected to the circuit unit are the same. Each of them is formed on a substrate, and the first sensor electrode for each of the laminates is connected to the first circuit unit electrode, and the second sensor electrode is connected to the second circuit unit electrode. A sensor unit in which the pressure-sensitive sensor is electrically connected to the circuit portion, and the plurality of pressure-sensitive sensors are arranged in a state of being separated from each other via a space portion, and the first one for each of the laminated bodies. The sensor electrode and the second sensor electrode are formed on the substrate, and the second electrode layer of the laminate adjacent to the substrate is formed on the surface of the dielectric layer on the side far from the substrate. The member sandwiched between the second electrode layer and the second sensor electrode is provided with a conductive structure portion that has flexibility and penetrates in the thickness direction in a state of being insulated from the first electrode layer. The second electrode layer is connected to the second sensor electrode via the conduction structure portion.

According to the above configuration, in the sensor unit, the first sensor electrode for each laminate in each pressure sensitive sensor is connected to the first circuit unit electrode, and the second sensor electrode is connected to the second circuit unit electrode. Then, each pressure sensor is electrically connected to the circuit unit.

The connection of the first sensor electrode to the first circuit portion electrode and the connection of the second sensor electrode to the second circuit portion electrode of each laminate are made on the substrate. In the laminate adjacent to the substrate, the connection of the second electrode layer formed on the surface of the dielectric layer far from the substrate to the second sensor electrode is sandwiched between the second electrode layer and the second sensor electrode. This is done through a conductive structure provided on the member. Since the conductive structure portion has flexibility and penetrates the dielectric layer or the like in the thickness direction, it deforms following the expansion and contraction of the dielectric layer. Moreover, the conductive structure portion is insulated from the first electrode layer. Therefore, unlike the case where the connection of the second electrode layer to the second sensor electrode is made by the wiring portion provided outside the pressure-sensitive sensor, the conductive structure portion is less likely to be disconnected. Further, since the connection of the second electrode layer to the second sensor electrode is realized by the conductive structure portion extending in the thickness direction of the substrate, the wiring structure is simplified. Further, it is possible to increase the ratio of the pressure-sensitive sensor to the sensor unit and increase the mounting density of the pressure-sensitive sensor.

In the sensor unit, each pressure-sensitive sensor includes a plurality of the laminated bodies laminated in the thickness direction, and the first electrode layer in the laminated body adjacent to the substrate is formed on the same substrate. Further, when the conductive structure portion is connected to the first circuit portion electrode via the first sensor electrode and the conductive structure portion is used as the second conductive structure portion, the first electrode layer in the laminated body not adjacent to the substrate. Is formed on the surface of the dielectric layer in the same laminate on the side farther from the substrate, the first electrode layer in the laminate adjacent to the substrate, and the first electrode layer in the laminate not adjacent to the substrate. The member sandwiched between the one electrode layer and the first electrode layer is provided with a first conductive structure portion that has flexibility and penetrates in the thickness direction in a state of being insulated from the second electrode layer, and both first electrode layers. Is preferably connected via the first conductive structure portion.

According to the above configuration, in the laminated body adjacent to the substrate, the connection of the first electrode layer to the first circuit portion electrode is made on the substrate via the first sensor electrode. In the laminated body not adjacent to the substrate, the connection of the first sensor electrode to the first circuit portion electrode is made on the substrate.

Further, in the laminated body not adjacent to the substrate, the first electrode layer is connected to the first circuit portion electrode of the first electrode layer formed on the surface of the dielectric layer on the side far from the substrate in the laminated body. This is done by connecting to the first electrode layer of the laminate adjacent to the substrate. The connection between the first electrode layers is made via a first conductive structure portion provided in a member sandwiched between the first electrode layers. Since the first conductive structure portion has flexibility and penetrates the dielectric layer or the like in the thickness direction, it deforms following the expansion and contraction of the dielectric layer. Moreover, the first conductive structure portion is insulated from the second electrode layer. Therefore, unlike the case where both first electrode layers are connected by a wiring portion provided outside the pressure-sensitive sensor, disconnection is unlikely to occur in the first conduction structure portion. Further, since the connection between the two first electrode layers is realized by the first conductive structure portion extending in the thickness direction of the substrate, the wiring structure is simplified. In this way, the wiring structure is further simplified and the connection reliability is further improved.

Even if at least one of the first conductive structure portion and the second conductive structure portion is composed of a through hole extending in the thickness direction and a flexible conductive paste arranged in the through hole. Alternatively, it may be composed of through holes extending in the thickness direction.

Both the through hole and the combination of the conductive paste and the through hole are deformed according to the expansion and contraction of the dielectric layer. Therefore, the effect of improving the connection reliability while simplifying the wiring structure can be obtained.

According to the present invention, in a sensor unit including a plurality of pressure-sensitive sensors, it is possible to improve connection reliability while simplifying the wiring structure.

The perspective view which shows the schematic structure of the sensor unit in one Embodiment. The plan view of the sensor unit of FIG. The side view of the sensor unit of FIG. The bottom view of the sensor unit of FIG. FIG. 3 is a partial cross-sectional view taken along line 5-5 of FIG. FIG. 6 is a partial cross-sectional view taken along the line 6-6 of FIG. FIG. 2 is a partial cross-sectional view taken along the line 7-7 of FIG. FIG. 2 is a partial cross-sectional view taken along the line 8-8 of FIG. FIG. 2 is a partial cross-sectional view taken along line 9-9 of FIG.

Hereinafter, an embodiment of the sensor unit will be described with reference to the drawings.
The dimensional ratios in the drawings are exaggerated for convenience of explanation and differ from the actual ratios.
As shown in FIGS. 1 to 3, the sensor unit 10 includes a flexible substrate 11, a plurality of pressure-sensitive sensors 12A and 12B arranged on the substrate 11, and the above-mentioned feelings. It includes a circuit unit 30 arranged on the substrate 11 in a state of being separated from the pressure sensors 12A and 12B. These pressure-sensitive sensors 12A and 12B and the circuit unit 30 are arranged in a row in the present embodiment.

The substrate 11 is composed of a flexible printed wiring board (FPC: an abbreviation for Flexible Printed Circuits). The flexible printed wiring board is a form of a printed circuit board, in which a wiring pattern (wiring portion) made of copper foil or the like is formed on a thin film formed of a resin material such as polyimide, polyethylene terephthalate, polyethylene naphthalate, or polycarbonate. It is thin, light, and has the characteristics of being bendable.

The circuit unit 30 includes a detection unit that converts physical changes of both pressure-sensitive sensors 12A and 12B into electrical signals, a processing unit that performs processing using the detection results obtained by the detection unit, and processing results of the processing unit. It is provided with a transmission unit that transmits the power to the outside by wireless communication, and a battery unit that supplies power to the pressure-sensitive sensors 12A and 12B, a detection unit, a processing unit, and a transmission unit. As the battery unit, a primary battery may be used, or a secondary battery or a power storage device such as a capacitor may be used.

Each of the pressure-sensitive sensors 12A and 12B is a sensor that detects the pressure applied thereto, and is lightweight and has flexibility. In this embodiment, a capacitance type pressure sensor is used as the pressure sensitive sensors 12A and 12B. Further, both pressure-sensitive sensors 12A and 12B are arranged on the substrate 11 in a state of being separated from each other via the space portion S1.

Each of the pressure-sensitive sensors 12A and 12B is configured by a dielectric elastomer actuator that expands and contracts in the thickness direction, and has the same configuration as each other. Each of the pressure-sensitive sensors 12A and 12B has at least one laminated body in which the dielectric layer 17 is sandwiched between the first electrode layer and the second electrode layer having different polarities in the thickness direction of the substrate 11, and two in the present embodiment. I have. Here, in order to distinguish between the two laminates, the laminate on the side closer to the substrate 11 (adjacent side) is referred to as the laminate 13, and the laminate on the side farther from the substrate 11 (non-adjacent side) is referred to as the laminate 14. Let's say. The pressure-sensitive sensors 12A and 12B are arranged on the substrate 11 so that the thickness direction of the dielectric layer 17 coincides with the thickness direction of the substrate 11.

Further, in the present embodiment, the first electrode layer is composed of the positive electrode layer 15, and the second electrode layer is composed of the negative electrode layer 16. The negative electrode layer 16 in the laminated body 13 also serves as the negative electrode layer 16 in the laminated body 14. In other words, the negative electrode layers in the adjacent laminates 13 and 14 are composed of a common negative electrode layer 16.

Examples of the materials forming both the positive electrode layer 15 and the negative electrode layer 16 in the laminated bodies 13 and 14 include conductive elastomer, carbon nanotube, Ketjen black (registered trademark), metal foil such as copper and aluminum, and metal. A vapor deposition film can be mentioned. Examples of the conductive elastomer include a conductive elastomer containing an insulating polymer and a conductive filler.

Examples of the insulating polymer include crosslinked polyrotaxane, silicone elastomer, acrylic elastomer, and urethane elastomer. One of these insulating polymers may be used, or a plurality of types may be used in combination. Examples of the conductive filler include metal particles such as Ketjen Black (registered trademark), carbon black, and copper and silver. One of these conductive fillers may be used, or a plurality of types may be used in combination.

The dielectric layer 17 for each of the laminated bodies 13 and 14 is formed of a dielectric elastomer and has a sheet shape. The dielectric elastomer is not particularly limited, and known dielectric elastomers such as crosslinked polyrotaxane, silicone elastomer, acrylic elastomer, and urethane elastomer can be used. One of these dielectric elastomers may be used, or a plurality of types may be used in combination.

The capacitances of the pressure-sensitive sensors 12A and 12B made of dielectric elastomer actuators are inversely proportional to the electrode spacing between the positive electrode layer 15 and the negative electrode layer 16 and proportional to the electrode area (opposing area), and the pressure-sensitive sensors 12A and 12B. It changes according to the shape of. Therefore, when an external force acts on the pressure-sensitive sensors 12A and 12B and the pressure-sensitive sensors 12A and 12B are compressed in the thickness direction of the dielectric layer 17, the capacitance increases. There is a difference between the capacitance of the pressure-sensitive sensors 12A and 12B when no external force is applied and the capacitance of the pressure-sensitive sensors 12A and 12B when an external force is applied. From these facts, the pressure-sensitive sensors 12A and 12B can detect the pressure applied to the pressure-sensitive sensors 12A and 12B according to the change in capacitance.

Further, the pressure-sensitive sensors 12A and 12B configured by laminating the two laminated bodies 13 and 14 in the thickness direction of the dielectric layer 17 as described above have the positive electrode layer 15 and the negative electrode layer 16 inverted upside down2. The configuration is such that two capacitors are stacked, and both positive electrode layers 15 are electrically connected. By making the pressure sensitive sensors 12A and 12B have a two-layer structure as described above, when the pressure sensitive sensors 12A and 12B are exposed to an external electromagnetic field, one capacitor and the other capacitor have opposite-phase voltage or reverse. Since phase currents are generated and when they are added, they become zero, the influence of noise due to the external electromagnetic field can be eliminated.

As shown in FIGS. 2 to 4, in any of the pressure-sensitive sensors 12A and 12B, a common first sensor electrode 21 is connected to both positive electrode layers 15 for each of the laminated bodies 13 and 14. On the other hand, in the pressure-sensitive sensor 12A on the side close to the circuit unit 30, a common second sensor electrode 22 is connected to the negative electrode layer 16 for each of the laminated bodies 13 and 14. In the pressure-sensitive sensor 12B on the side far from the circuit unit 30, a common second sensor electrode 23 is connected to the negative electrode layer 16 for each of the laminated bodies 13 and 14.

The first sensor electrode 21 for each of the laminated bodies 13 and 14 is formed on the surface of the substrate 11 on the same side as the surface on which the circuit unit 30 is arranged, and the second sensor electrodes 22 and 23 are the first sensor electrodes. It is formed on the surface opposite to 21.

The positive electrode layer 15 in the laminated body 13 is formed on the surface of the substrate 11 on the same side as the surface on which the circuit portion 30 is arranged, and is connected to the first sensor electrode 21. The positive electrode layer 15 in the laminated body 14 is formed on the surface of the dielectric layer 17 in the laminated body 14 on the side far from the substrate 11.

The negative electrode layer 16 in the laminated body 13 is formed on the surface of the dielectric layer 17 in the laminated body 13 on the side far from the substrate 11. In other words, the negative electrode layer 16 for each laminated body 14 is formed on the surface of the laminated body 14 on the side closer to the substrate 11 with respect to the dielectric layer 17.

One first circuit unit electrode 31 and two second circuit unit electrodes 32 and 33 are electrically connected to the circuit unit 30 as a part of the wiring unit, respectively. The first circuit unit electrode 31 is formed on the surface of the substrate 11 on the same side as the surface on which both pressure-sensitive sensors 12A and 12B and the circuit unit 30 are arranged. Both the second circuit unit electrodes 32 and 33 are formed on the surface of the substrate 11 opposite to the first circuit unit electrode 31. Both second circuit unit electrodes 32 and 33 penetrate the substrate 11 in the thickness direction and are connected to the circuit unit 30.

In the pressure-sensitive sensor 12A, the first sensor electrode 21 is directly connected to the first circuit unit electrode 31. In the pressure-sensitive sensor 12B, the first sensor electrode 21 is connected to the positive electrode layer 15 of the pressure-sensitive sensor 12A, and is indirectly connected to the first circuit unit electrode 31 via the positive electrode layer 15 and the first sensor electrode 21. Is connected. Further, the second sensor electrode 22 is connected to the second circuit unit electrode 32, and the second sensor electrode 23 is connected to the second circuit unit electrode 33.

As shown in FIGS. 5, 6 and 8, in the pressure-sensitive sensor 12A, the member sandwiched between the negative electrode layer 16 and the second sensor electrode 22 has flexibility and is relative to the positive electrode layer 15. A second conductive structure portion 37 that penetrates the substrate 11 in the thickness direction in an insulated state is provided as a part of the conductive structure portion. The corresponding members are the dielectric layer 17 on the side close to the substrate 11, the positive electrode layer 15 on the side close to the substrate 11, and the substrate 11.

As shown in FIGS. 5, 6 and 9, in the pressure-sensitive sensor 12B, the member sandwiched between the negative electrode layer 16 and the second sensor electrode 23 has flexibility and is relative to the positive electrode layer 15. A second conductive structure portion 37 that penetrates the substrate 11 in the thickness direction in an insulated state is provided as a part of the conductive structure portion. The corresponding members are the dielectric layer 17 on the side close to the substrate 11, the positive electrode layer 15 on the side close to the substrate 11, and the substrate 11.

Each of the second conductive structure portions 37 is formed in a dielectric layer 17 on the side close to the substrate 11, a positive electrode layer 15 on the side close to the substrate 11, a through hole 38 penetrating the substrate 11 in the thickness direction, and a positive electrode layer 15. It is formed of a conductive paste 39 which is formed in the through hole 38 in an insulated state and has flexibility. The conductive paste 39 is filled in the through hole 38 in the dielectric layer 17 and the substrate 11. The through hole 38 is formed in the positive electrode layer 15 to have a larger diameter than that in the dielectric layer 17 and the substrate 11. In the positive electrode layer 15, the conductive paste 39 penetrates in a state of being separated from the inner wall surface of the through hole 38, that is, in an insulated state. The conductive paste 39 can be obtained, for example, by adding a metal powder such as silver or copper to silicone rubber, and can be deformed by following the expansion and contraction of the dielectric layer 17. Then, as shown in FIGS. 8 and 9, in the pressure-sensitive sensor 12A, the negative electrode layer 16 is connected to the second sensor electrode 22 via the second conductive structure portion 37. Further, in the pressure-sensitive sensor 12B, the negative electrode layer 16 is connected to the second sensor electrode 23 via the second conductive structure portion 37.

As shown in FIGS. 5 to 7, in the laminated body 14 of the pressure-sensitive sensors 12A and 12B, the first circuit portion electrode of the positive electrode layer 15 formed on the surface of the dielectric layer 17 far from the substrate 11. The connection to 31 is made by connecting the positive electrode layer 15 to the positive electrode layer 15 of the laminated body 13. In each of the pressure-sensitive sensors 12A and 12B, the members sandwiched between the positive electrode layers 15, that is, the dielectric layer 17 and the negative electrode layer 16 have flexibility and are insulated from the negative electrode layer 16. A first conductive structure portion 34 that penetrates the substrate 11 in the thickness direction is provided in this state.

The first conductive structure portion 34 for each of the pressure sensitive sensors 12A and 12B is in a state of being insulated from the negative electrode layer 16 and the through hole 35 penetrating the dielectric layer 17 and the negative electrode layer 16 in the thickness direction of the substrate 11. It is composed of a conductive paste 36 formed in the through hole 35 and having flexibility. As the conductive paste 36, the same one as the conductive paste 39 is used. The conductive paste 36 is filled in the through hole 35 in both dielectric layers 17. The through hole 35 is formed in the negative electrode layer 16 to have a larger diameter than in both dielectric layers 17. The conductive paste 36 penetrates the negative electrode layer 16 in a state of being separated from the inner wall surface of the through hole 35, that is, in an insulated state. The positive electrode layers 15 for each of the pressure-sensitive sensors 12A and 12B are connected to each other via the first conductive structure portion 34.

The sensor unit 10 of the present embodiment is configured as described above. Next, the operation of the sensor unit 10 will be described. In addition, the effects caused by the action will also be described.

In the sensor unit 10 of the present embodiment, the first sensor electrode 21 for each of the laminated bodies 13 and 14 in the pressure sensitive sensors 12A and 12B is connected to the first circuit unit electrode 31, and the second sensor electrode 22 is the second circuit unit. The pressure-sensitive sensors 12A and 12B are electrically connected to the circuit unit 30 by being connected to the electrode 32 and the second sensor electrode 23 being connected to the second circuit unit electrode 33.

The connection of the first sensor electrode 21 for each of the laminates 13 and 14 to the first circuit portion electrode 31 is made on the substrate 11. In each of the laminated bodies 13 and 14, the connection of the second sensor electrode 22 to the second circuit portion electrode 32 and the connection of the second sensor electrode 23 to the second circuit portion electrode 33 are made on the substrate 11.

As shown in FIG. 8, in the laminated body 13 of the pressure-sensitive sensor 12A, the connection of the negative electrode electrode layer 16 formed on the surface of the dielectric layer 17 far from the substrate 11 to the second sensor electrode 22 is the same negative electrode. It is formed via a second conductive structure portion 37 provided in a member sandwiched between the electrode layer 16 and the second sensor electrode 22. Similarly, as shown in FIG. 9, in the laminated body 13 of the pressure-sensitive sensor 12B, the connection of the negative electrode layer 16 formed on the surface of the dielectric layer 17 far from the substrate 11 to the second sensor electrode 23 is This is done via a second conductive structure portion 37 provided in a member sandwiched between the negative electrode layer 16 and the second sensor electrode 23.

As shown in FIGS. 8 and 9, each of the second conductive structure portions 37 has flexibility and penetrates the dielectric layer 17 and the like in the thickness direction, and therefore deforms following the expansion and contraction of the dielectric layer 17. do. Moreover, each second conductive structure portion 37 is insulated from the positive electrode layer 15. Therefore, unlike the case where the negative electrode layer 16 is connected to the second sensor electrodes 22 and 23 by the wiring portion provided outside the pressure sensitive sensors 12A and 12B, the second conductive structure portion 37 is disconnected. It is unlikely to occur. Further, since the connection of the negative electrode layer 16 to the second sensor electrodes 22 and 23 is realized by the second conductive structure portion 37 extending in the thickness direction of the substrate 11, the wiring structure is simplified.

As described above, according to the present embodiment, in the sensor unit 10 including the plurality of pressure-sensitive sensors 12A and 12B, the connection reliability can be improved while simplifying the wiring structure, and the pressure-sensitive sensor 12A occupying the sensor unit 10 , 12B ratio can be increased to increase the mounting density of the pressure sensor.

Further, in the sensor unit 10 of the present embodiment, as shown in FIG. 7, in the laminated body 13 for each of the pressure sensitive sensors 12A and 12B, the connection of the positive electrode layer 15 to the first sensor electrode 21 is also made by the first sensor electrode 21. The connection to the first circuit unit electrode 31 is also made on the substrate 11.

In the laminated body 14 for each of the pressure-sensitive sensors 12A and 12B, the first sensor electrode 21 is connected to the first circuit portion electrode 31 on the substrate 11. Further, in the laminated body 14 for each of the pressure sensitive sensors 12A and 12B, the connection of the positive electrode layer 15 formed on the surface of the dielectric layer 17 far from the substrate 11 to the first circuit portion electrode 31 is the same positive electrode. The layer 15 is formed by being connected to the positive electrode layer 15 of the laminated body 13. The connection of both positive electrode layers 15 in the pressure sensitive sensors 12A and 12B is made via a first conductive structure portion 34 provided in a member sandwiched by both positive electrode layers 15. Since each of the first conductive structure portions 34 has flexibility and penetrates the dielectric layer 17 and the like in the thickness direction, it deforms following the expansion and contraction of the dielectric layer 17. Moreover, each first conductive structure portion 34 is insulated from the negative electrode layer 16. Therefore, unlike the case where the positive electrode layers 15 are connected by the wiring portions provided outside the pressure-sensitive sensors 12A and 12B, the first conductive structure portions 34 are less likely to be disconnected. Further, since the connection between the positive electrode layers 15 is realized by the first conductive structure portion 34 extending in the thickness direction of the substrate 11, the wiring structure is simplified. Therefore, the connection reliability can be further improved while further simplifying the wiring structure, and the ratio of the pressure-sensitive sensors 12A and 12B to the sensor unit 10 can be increased to increase the mounting density of the pressure-sensitive sensors. can.

By the way, the sensor unit 10 has a thickness of the substrate 11 in a portion of the substrate 11 on which hard parts such as the circuit portion 30 are not arranged, for example, in a region between the circuit portion 30 and the pressure-sensitive sensor 12A adjacent to the circuit portion 30. It can be bent in the direction. Since the pressure sensors 12A and 12B also have flexibility, they can be slightly curved. Therefore, furniture, shelves, boxes, tools, robot hands, and other items with various external shapes are targeted for attachment (attached portion), and the sensor unit 10 is bent to match the external shape of the attached portion. It can be transformed. Since the wiring portion constitutes a part of the substrate 11 and has flexibility, there is no problem even if it is bent. Then, the sensor unit 10 is attached to the attached portion by a double-sided adhesive tape or the like.

In the sensor unit 10 attached to the attached portion as described above, when pressure is applied to the pressure-sensitive sensors 12A and 12B, the capacitance changes according to the pressure. In the pressure-sensitive sensors 12A and 12B, the pressure is detected based on the change in capacitance. In the processing unit, processing is performed using the detection results of a plurality of (two) pressure sensors 12A and 12B. The processing result of the processing unit is wirelessly transmitted from the transmission unit.

According to this embodiment, the following effects can be obtained in addition to the above.
-Since the first conductive structure portion 34 and the second conductive structure portion 37 have a simple wiring structure, the sensor unit 10 can be miniaturized.

-In the space S1 between the adjacent pressure sensors 12A and 12B, the pressure cannot be detected or is difficult to detect as in the pressure sensors 12A and 12B. In this respect, in the present embodiment, since the connection is made inside the pressure sensors 12A and 12B, the number of connections made outside the pressure sensors 12A and 12B is reduced. Therefore, the size of the space S1 between the adjacent pressure-sensitive sensors 12A and 12B can be reduced, and the area where the pressure cannot be detected or is difficult to detect in the sensor unit 10 can be reduced, and the feeling occupied by the sensor unit 10 can be reduced. The ratio of the pressure sensors 12A and 12B can be increased to increase the mounting density of the pressure sensor.

It should be noted that the above embodiment can also be implemented as a modified example in which this is modified as follows. The above embodiment and the following modifications can be implemented in combination with each other within a technically consistent range.

-Unlike the above embodiment, the first electrode layer may be composed of the negative electrode layer 16 and the second electrode layer may be composed of the positive electrode layer 15.
At least one of the first conductive structure portion 34 and the second conductive structure portion 37 may be formed by through holes that can be deformed by following the expansion and contraction of the dielectric layer 17. In this case, only a part of the plurality of first conductive structure portions 34 may be composed of through holes, or all of them may be composed of through holes. The same applies to the plurality of second conductive structure portions 37.

The through hole includes a through hole that penetrates the dielectric layer 17 and the like in the thickness direction, and a conductive metal plating layer formed on the inner wall surface of the through hole. That is, the conductive pastes 36 and 39 formed in the through holes 35 and 38 in the above embodiment are replaced with the metal plating layer. The metal plating layer is applied with a thickness that allows it to be deformed by following the expansion and contraction of the dielectric layer 17.

Even in the case of such a change, the effect of improving the connection reliability while simplifying the wiring structure can be obtained as in the above embodiment.
-The number of laminated bodies 13 and 14 in each pressure sensitive sensor 12A and 12B may be changed to 1 or 3 or more.

In the above embodiment, two first circuit unit electrodes 31 are provided, and the first sensor electrode 21 in the pressure sensor 12A and the first sensor electrode 21 in the pressure sensor 12B are separate first circuit unit electrodes 31. May be connected to.

The number of pressure-sensitive sensors 12A and 12B used in the sensor unit 10 may be 3 or more. When a large number of pressure sensors 12A and 12B are used, it is desirable that they are arranged in a regular arrangement in a grid pattern (a grid pattern) in the vertical and horizontal directions. In this case, the adjacent pressure sensors 12A and 12B can be arranged in close proximity to each other, and the space portion S1 can be reduced.

Further, when many pressure sensors 12A and 12B are used, it is possible to detect the pressure distribution.
-The second circuit unit electrodes 32 and 33 are standardized, the second sensor electrodes 22 and 23 are standardized, and the common second sensor electrode is connected to the common second circuit unit electrode. May be done.

10 ... Sensor unit 11 ... Substrate 12A, 12B ... Pressure sensitive sensor 13, 14 ... Laminated body 15 ... Positive electrode layer (first electrode layer)
16 ... Negative electrode layer (second electrode layer)
17 ... Dielectric layer 21 ... 1st sensor electrode 22, 23 ... 2nd sensor electrode 30 ... Circuit part 31 ... 1st circuit part electrode 32, 33 ... 2nd circuit part electrode 34 ... 1st conductive structure part (conducting structure part)
35, 38 ... Through holes 36, 39 ... Conductive paste 37 ... Second conductive structure part (conducting structure part)
S1 ... Spatial part

Claims (4)

A plurality of pressure-sensitive sensors, each of which has flexibility, and a circuit unit that performs processing using the detection results of the plurality of pressure-sensitive sensors are arranged on the flexible substrate.
Each pressure sensor is provided with at least one laminate in the thickness direction of the substrate, which is formed by sandwiching a dielectric layer between a first electrode layer and a second electrode layer having different polarities.
A first sensor electrode is connected to the first electrode layer of each laminate, a second sensor electrode is connected to the second electrode layer, and the first circuit unit electrode and the circuit unit are connected to the circuit unit, respectively. The second circuit unit electrode is formed on the substrate, and is formed on the substrate.
By connecting the first sensor electrode of each laminate to the first circuit unit electrode and connecting the second sensor electrode to the second circuit unit electrode, the pressure-sensitive sensor is connected to the circuit unit. A sensor unit that is electrically connected
The plurality of pressure-sensitive sensors are arranged so as to be separated from each other via a space portion.
The first sensor electrode and the second sensor electrode for each laminate are formed on the substrate, and the second electrode layer of the laminate adjacent to the substrate is the side of the dielectric layer far from the substrate. Formed on the surface of
The member sandwiched between the second electrode layer and the second sensor electrode is provided with a conductive structure portion that has flexibility and penetrates in the thickness direction in a state of being insulated from the first electrode layer. , The second electrode layer is a sensor unit connected to the second sensor electrode via the conduction structure portion. Each pressure-sensitive sensor includes a plurality of the laminated bodies laminated in the thickness direction.
The first electrode layer in the laminated body adjacent to the substrate is formed on the substrate and is connected to the first circuit unit electrode via the first sensor electrode.
When the conductive structure portion is used as the second conductive structure portion, the first electrode layer in the laminated body not adjacent to the substrate is formed on the surface of the dielectric layer in the laminated body on the side far from the substrate. Being done
The member sandwiched between the first electrode layer in the laminate adjacent to the substrate and the first electrode layer in the laminate not adjacent to the substrate has flexibility and the second electrode layer. The sensor unit according to claim 1, wherein a first conductive structure portion is provided so as to penetrate in the thickness direction in an insulated state, and both first electrode layers are connected via the first conductive structure portion. .. Claim that at least one of the first conductive structure portion and the second conductive structure portion is composed of a through hole extending in the thickness direction and a flexible conductive paste arranged in the through hole. 2. The sensor unit according to 2. The sensor unit according to claim 2, wherein at least one of the first conductive structure portion and the second conductive structure portion is composed of through holes extending in the thickness direction.

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