JP2023032325A - Sensor device and vehicle seat - Google Patents

Abstract

To suppress a damage in a connection part when a large load is applied to the connection part between a sheet-like electrode and a wiring pattern of a flexible substrate.SOLUTION: A sensor device includes: a sheet-like substrate having an insulation property; a sheet-like first electrode provided so as to be stacked on a first surface of the substrate and bonded to the first surface via first bonding means; and a flexible substrate provided so as be stacked on the first surface of the substrate. The first electrode has a non-bonding region not bonded to the first surface, in a part of a portion overlapping the first surface of the substrate. The flexible substrate includes an extension part extending to a position overlapping the non-bonding region of the first electrode. The extension part includes a first contact portion that contacts with the non-bonding region non-fixedly, in a portion overlapping the non-bonding region of the first electrode.SELECTED DRAWING: Figure 2

Description

The present invention relates to a sensor device and a vehicle seat.

Japanese Unexamined Patent Application Publication No. 2002-200002 discloses a sensor device provided in a vehicle seat, in which a sheet-shaped electrode and a wiring pattern on a substrate are connected by soldering.

WO2019/116919

However, since the sensor device of Patent Document 1 is used by being incorporated in a vehicle seat, when the user is seated on the vehicle seat, the connection between the sheet-like electrode and the wiring pattern on the substrate is formed by soldering. There is a possibility that a large load will be applied to the connection, and it is necessary to design the connection so that it will not break even in that case.

A sensor device according to one embodiment includes a sheet-like base material having insulating properties, and a sheet-like second base material provided over a first surface of the base material and adhered to the first surface by a first bonding means. and a flexible substrate overlaid on a first surface of a base material, the first electrode being a non-adhesive material that is not adhered to the first surface at a portion of a portion overlapping the first surface of the base material. The flexible substrate has an adhesive region, the flexible substrate has an extension extending to a position overlapping the non-adhesion region of the first electrode, and the extension has a non-adhesion region in a portion overlapping the non-adhesion region of the first electrode. It has a first contact portion in non-permanent contact with the adhesive area.

According to the sensor device according to one embodiment, when a large load is applied to the connection portion between the sheet-like electrode and the wiring pattern of the flexible substrate, damage to the connection portion can be suppressed.

1 is an external perspective view of a vehicle seat according to one embodiment; FIG. 1 is an exploded perspective view of a sensor device according to one embodiment; FIG. Sectional view of a sensor device according to one embodiment An exploded perspective view of a sensor device according to a modification of one embodiment.

An embodiment of the present invention will be described below with reference to the drawings.

(Structure of vehicle seat 10)
FIG. 1 is an external perspective view of a vehicle seat 10 according to one embodiment. As shown in FIG. 1 , the vehicle seat 10 includes a backrest portion 11 and a seat portion 12 . Each of the backrest portion 11 and the seat portion 12 has a plurality of sensor devices 100 inside the surface. Each of the plurality of sensor devices 100 can detect electrical signals emitted by the body of the user seated on the vehicle seat 10 .

(Structure of sensor device 100)
FIG. 2 is an exploded perspective view of the sensor device 100 according to one embodiment. FIG. 3 is a cross-sectional view of the sensor device 100 according to one embodiment, and is a cross-sectional view along a plane that passes through the center of the through hole 111 on the XY plane of FIG. 2 and is parallel to the XZ plane.

As shown in FIGS. 2 and 3, the sensor device 100 according to one embodiment includes a substrate 110, sensor electrodes 120, shield electrodes 130, and a flexible substrate 140. FIG.

The base material 110 is a sheet-like member having insulating properties and flexibility. A through hole 111 is provided in the central portion of the base material 110 . Through hole 111 has a circular shape in plan view. In this embodiment, the base material 110 uses a nonwoven fabric as an example of a "sheet-shaped member." A nonwoven fabric is a sheet-shaped member in which insulating fibers are entangled and stretched in a plane. Non-woven fabrics are made of synthetic fibers such as polyester and polyethylene, for example.

The sensor electrode 120 is a conductive sheet-like electrode provided over the second surface 110B (the surface on the Z-axis positive side) of the base material 110 . The sensor electrode 120 is an example of a "second electrode". The sensor electrode 120 is capacitively coupled with the body of the user seated on the vehicle seat 10, thereby detecting an electrical signal such as an electrocardiogram generated by the body of the user.

The shield electrode 130 is a conductive sheet-like electrode provided over the first surface 110A (surface on the Z-axis negative side) of the base material 110 . The shield electrode 130 is an example of a "first electrode". The shield electrode 130 functions as a shield for the surface of the sensor electrode 120 opposite to the surface facing the body (surface on the Z-axis negative side), and protects the surface of the sensor electrode 120 opposite to the surface facing the body from an object. It is provided to prevent the influence of capacitive coupling and noise, and to suppress the noise component from being superimposed on the electrical signal detected by the sensor electrode 120 .

The shield electrode 130 has its upper surface 130A (surface on the Z-axis positive side) attached to the first surface 110A of the base material 110 with a double-sided tape 151 (an example of a “first adhesive means”). However, the double-sided tape 151 has a notch portion 151A in which a part on the positive side of the X axis is cut out in a rectangular shape. As a result, a rectangular non-bonded area 131 that is not adhered to the first surface 110A of the base material 110 is formed on the upper surface 130A of the shield electrode 130 at a position overlapping the notch 151A.

In this embodiment, the sensor electrode 120 and the shield electrode 130 use conductive cloth as an example of a "sheet-shaped electrode." As the conductive cloth, for example, a cloth material whose surface is coated with a conductive material (for example, metal, carbon, etc.), a cloth material containing a conductive material, or the like is used.

The flexible substrate 140 is a flexible sheet-like member that is provided over the first surface 110</b>A of the base material 110 . The flexible board 140 is formed by providing a wiring pattern such as copper foil on a film-like resin base material having insulating properties and flexibility such as a polyimide film, and various electronic components are mounted on the flexible board 140 . Flexible substrate 140 has a base portion 141 and an extension portion 142 .

The base portion 141 is a portion having a rectangular shape with the Y-axis direction as the longitudinal direction and the X-axis direction as the lateral direction. The base 141 is arranged on the positive side of the X-axis with respect to the shield electrode 130 . A processing circuit 143 is mounted on the base 141 . Processing circuitry 143 drives sensor electrode 120 and shield electrode 130 and amplifies electrical signals detected by sensor electrode 120 . The flexible substrate 140 is attached to the first surface 110A of the base material 110 at the base portion 141 with a double-sided tape 152 (an example of the “second adhesive means”).

The extending portion 142 is a portion that extends linearly in the positive X-axis direction from the intermediate position of the base portion 141 in the Y-axis direction to the notch portion 151A of the double-sided tape 151 . The tip of the extending portion 142 (the end on the negative side of the X-axis) overlaps the non-bonded area 131 of the shield electrode 130 in the cutout portion 151A of the double-sided tape 151 . A first contact portion 144 and a second contact portion 145 made of a conductive material are provided at the tip portion (the end portion on the negative side of the X axis) of the extension portion 142 .

The first contact portion 144 is provided at the tip portion of the lower surface 142B (surface on the Z-axis negative side) of the extension portion 142 . The first contact portion 144 is provided at a position overlapping the through hole 111 of the base material 110 in plan view, and has a circular shape with a smaller diameter than the through hole 111 . The first contact portion 144 is provided so as to protrude slightly downward from the lower surface 142B of the extension portion 142 . The first contact portion 144 is arranged in the notch portion 151A of the double-sided tape 151 so as to face the non-adhesive region 131 of the shield electrode 130 and contact the non-adhesive region 131 of the shield electrode 130 in a non-fixed manner. . The first contact portion 144 is connected to the processing circuit 143 provided on the base portion 141 via a wiring pattern (not shown) provided on the lower surface 142B of the extension portion 142 . The first contact portion 144 is formed by printing a conductive film (for example, silver paste, carbon, etc.) on the wiring pattern. As described above, in this embodiment, the first contact portion 144 is formed separately from the wiring pattern, and is formed to project slightly downward from the lower surface 142B of the extension portion 142. However, the first contact portion 144 is It may be part of the wiring pattern.

The second contact portion 145 is provided at the tip portion of the upper surface 142A of the extension portion 142 (the surface on the Z-axis positive side). The second contact portion 145 is provided at a position overlapping the through hole 111 of the base material 110 in plan view, and has a circular shape with a smaller diameter than the through hole 111 . The second contact portion 145 is provided so as to protrude slightly upward from the upper surface 142A of the extension portion 142 . The second contact portion 145 is arranged in the notch portion 151A of the double-sided tape 151, and faces the lower surface (Z-axis negative side surface) of the sensor electrode 120 through the through hole 111 of the base material 110. It becomes possible to contact the lower surface of the electrode 120 (surface on the Z-axis negative side). The second contact portion 145 is connected to the processing circuit 143 provided on the base portion 141 via a wiring pattern (not shown) provided on the upper surface 142A of the extension portion 142 . The second contact portion 145 is formed by printing a conductive film (for example, silver paste, carbon, etc.) on the wiring pattern. As described above, in the present embodiment, the second contact portion 145 is formed separately from the wiring pattern and is formed to protrude slightly upward from the upper surface 142A of the extension portion 142. However, the second contact portion 145 is It may be part of the wiring pattern.

(Installation example of sensor device 100)
A sensor device 100 according to one embodiment is arranged inside the vehicle seat 10 as shown in FIG. 3 . Specifically, the vehicle seat 10 has a seat body portion 14 made of urethane or the like, and a seat cover 15 that covers the seat body portion 14 . The sensor device 100 is arranged between the seat body portion 14 and the seat cover 15 so that the sensor electrode 120 is on the seat cover 15 side and the shield electrode 130 is on the seat body portion 14 side.

(Operation of sensor device 100)
In the sensor device 100 according to one embodiment, when the user is not seated on the vehicle seat 10 , the sensor electrode 120 contacts the second contact portion 145 provided on the extension portion 142 of the flexible substrate 140 . not. Also, the first contact portion 144 provided on the extension portion 142 is in non-fixed contact with the non-bonded area 131 of the shield electrode 130 .

On the other hand, in the sensor device 100 according to one embodiment, when the user sits on the vehicle seat 10 , the sensor electrode 120 is pressed by the user, thereby causing the second electrode 120 provided on the extension portion 142 of the flexible substrate 140 to move. The sensor electrode 120 contacts the contact portion 145 through the through hole 111 of the base material 110 . Thereby, the sensor electrode 120 is electrically connected to the wiring pattern provided on the extension portion 142 of the flexible substrate 140 . Therefore, an electric signal detected by the user by the sensor electrode 120 is transmitted to the processing circuit 143 mounted on the base portion 141 of the flexible substrate 140 via the wiring pattern provided on the extension portion 142 of the flexible substrate 140. output. The electrical signal detected by the sensor electrodes 120 from the user is then amplified by the processing circuitry 143 .

At this time, the extending portion 142 of the flexible substrate 140 is not fixed to either the sensor electrode 120 or the shield electrode 130 , so the first contact portion 144 provided on the extending portion 142 is connected to the shield electrode 130 . can be moved in the horizontal direction (direction parallel to the XY plane) within the cutout portion 151A of the double-sided tape 151 while being in non-fixed contact with the non-adhesive region 131 of the double-sided tape 151 . Accordingly, in the sensor device 100 according to one embodiment, the load applied to the connecting portion between the first contact portion 144 and the shield electrode 130 due to the user sitting on the seat can be relieved by the horizontal movement of the extension portion 142. Therefore, breakage of the connecting portion between the first contact portion 144 and the shield electrode 130 does not occur. Therefore, according to the sensor device 100 according to one embodiment, when a large load is applied to the connection portion between the sheet-like shield electrode 130 and the wiring pattern of the flexible substrate 140, damage to the connection portion can be suppressed. can.

Moreover, in the sensor device 100 according to one embodiment, the flexible substrate 140 has a base portion 141 and an extension portion 142 extending from the base portion 141 . 1 is adopted.
Accordingly, in the sensor device 100 according to one embodiment, the shield electrode 130 and the flexible substrate 140 can be held by the base material 110, and the extending portion 142 of the flexible substrate 140 can be held with respect to the shield electrode 130. can be relatively displaced (horizontal movement). As described above, since the sensor device 100 according to one embodiment holds the shield electrode 130 and the flexible substrate 140 on the base material 110, a large displacement (horizontal movement) of the shield electrode 130 and the flexible substrate 140 is allowed. can do things

(Modification)
FIG. 4 is an exploded perspective view of the sensor device 100 according to a modified example of one embodiment. The sensor device 100 shown in FIG. 4 includes a flexible substrate 140 in which a base portion 141 and an extension portion 142 are separately provided, and a connection member 146 electrically connecting the base portion 141 and the extension portion 142. have As the connection member 146, for example, an electric cable, a flexible substrate, or the like is used.

Base 141 is mounted with processing circuitry 143 that amplifies electrical signals detected by sensor electrodes 120 . Base 141 is attached to first surface 110A of base material 110 with double-sided tape 152 .

The extending portion 142 is spaced apart in the positive X-axis direction from an intermediate position in the Y-axis direction of the base portion 141, and extends linearly in the positive X-axis direction to the notch portion 151A of the double-sided tape 151. extend to The extension part 142 has a tip part where the first contact part 144 and the second contact part 145 are provided, and is arranged in the notch part 151 A of the double-sided tape 151 . The extending portion 142 is horizontally movable without being fixed to any member. An electrical signal detected by sensor electrode 120 is supplied to processing circuit 143 mounted on base 141 via extension 142 and connecting member 146 .

According to the sensor device 100 according to the modified example of the embodiment, since the base 141 and the extension 142 of the flexible substrate 140 are provided separately, the base 141 can be fixed to the base material 110. Since the substrate 110 does not interfere with the horizontal movement of the base portion 141, the degree of freedom of horizontal movement of the extension portion 142 within the notch portion 151A of the double-sided tape 151 can be increased.

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to these embodiments, and various modifications or Change is possible.

For example, although the sensor electrode 120 and the shield electrode 130 are formed using a conductive cloth in this embodiment, they may be formed using a flexible substrate. In that case, the electrode-formed surface of the flexible substrate is arranged to face the flexible substrate 140 so that the sensor electrode 120 or the shield electrode 130 can contact the second contact portion 145 or the first contact portion 144 .

Further, the sensor device 100 may have the projecting portion 153 at a position of the seat main body portion 14 or the seat cover 15 overlapping the first contact portion 144 and the second contact portion 145 in plan view.

For example, as shown in FIG. 3, the vehicle seat 10 has a projecting portion 153 at a position overlapping the first contact portion 144 in plan view on the surface of the seat body portion 14 (the surface on the Z-axis positive side). You may As a result, the vehicle seat 10 can deform a portion of the shield electrode 130 (the contact portion with the first contact portion 144) into a convex shape. The portion 144 can be easily accessible. The projecting portion 153 may be formed integrally with the vehicle seat 10, or may be formed separately and integrated by being attached.

Further, although not shown, the vehicle seat 10 has, for example, a protruding portion 153 at a position overlapping the second contact portion 145 in plan view on the back surface of the seat cover 15 (the surface on the Z-axis negative side). You may As a result, the vehicle seat 10 can deform a portion of the sensor electrode 120 (the contact portion with the second contact portion 145) into a convex shape. can be made accessible to a portion of the The protruding portion 153 may be formed integrally with the seat cover 15, or may be formed separately and integrated by being attached.

For example, the protrusion 153 may be formed by rubber molding, printing, UV resin, or the like.

A similar projecting portion 153 may be provided at a position overlapping the second contact portion 145 in plan view on the sensor electrode 120 or at a position overlapping the first contact portion 144 in plan view on the shield electrode 130 . Incidentally, the projecting portion 153 is formed separately and integrated with the sensor electrode 120 or the shield electrode 130 by, for example, attaching them.

Further, in the sensor device 100, the first contact portion 144 may be provided at a position that does not overlap the through hole 111 of the base material 110 in plan view. As a result, the sensor device 100 can prevent the pressing force applied to the first contact portion 144 from being attenuated by the through hole 111 , so that the first contact portion 144 is more reliably brought into contact with the shield electrode 130 . can be made

In the sensor device 100 , the shield electrode 130 (first electrode) may have a conductive film (for example, silver paste, carbon, etc.) formed by printing on the contact portion with the first contact portion 144 . This allows the sensor device 100 to more reliably bring the shield electrode 130 into contact with the first contact portion 144 .

Further, in the sensor device 100 , the sensor electrode 120 (second electrode) may have a conductive film (for example, silver paste, carbon, etc.) formed by printing or the like on the contact portion with the second contact portion 145 . Thereby, the sensor device 100 can more reliably bring the sensor electrode 120 into contact with the second contact portion 145 .

REFERENCE SIGNS LIST 10 vehicle seat 11 backrest portion 12 seat portion 14 seat body portion 15 seat cover 100 sensor device 110 base material 110A first surface 110B second surface 111 through hole 120 sensor electrode (second electrode)
130 shield electrode (first electrode)
131 non-bonded area 140 flexible substrate 141 base 142 extension 142A upper surface 142B lower surface 143 processing circuit 144 first contact portion 145 second contact portion 146 connection member 151 double-sided tape 151A notch portion 152 double-sided tape 153 protruding portion

Claims (10)

a sheet-like base material having insulating properties;
a sheet-like first electrode provided over the first surface of the base material and adhered to the first surface by a first adhesion means;
a flexible substrate overlaid on the first surface of the base material;
The first electrode is
Having a non-adhesive region that is not adhered to the first surface in part of the portion overlapping the first surface of the base material,
The flexible substrate is
having an extension extending to a position overlapping with the non-bonded region of the first electrode;
The extending portion is
A sensor device, comprising: a first contact portion that is in non-fixed contact with the non-bonded region in a portion of the first electrode that overlaps the non-bonded region. The flexible substrate is
Having a base and the extension extending from the base,
2. The sensor device according to claim 1, wherein the base is adhered to the first surface of the substrate by a second adhesive means. The flexible substrate is
a base on which processing circuitry is provided;
the extension portion that is separate from the base portion;
3. The sensor device according to claim 1, further comprising a connection member that electrically connects the base portion and the extension portion. Further comprising a sheet-like second electrode provided over the second surface of the base material,
The extending portion is
Having a second contact portion contactable with the second electrode in a portion overlapping with the second electrode,
The base material is
The sensor device according to any one of claims 1 to 3, further comprising a through hole at a position overlapping with the second contact portion. The first contact portion is
The sensor device according to claim 4, wherein the sensor device is provided at a position that does not overlap with the through hole of the base material in plan view. The first electrode is
The sensor device according to any one of claims 1 to 5, wherein a conductive film is formed on a contact portion with the first contact portion. The sensor according to any one of Claims 1 to 6, further comprising a projecting portion that deforms a part of the first electrode into a projecting shape at a position that overlaps with the first contact portion in plan view. Device. The second electrode is
The sensor device according to claim 4 or 5, wherein a conductive film is formed on a contact portion with the second contact portion. 9. The method according to any one of claims 4, 5, and 8, further comprising a projecting portion that deforms a part of the second electrode into a projecting shape at a position that overlaps with the second contact portion in plan view. sensor device. A vehicle seat comprising the sensor device according to any one of claims 1 to 9.

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