JP2017004795A - Holding detection device and capacitive sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a capacitive sensor which easily dispose a plurality of electrodes at appropriate positions in the case of integration into a rim.SOLUTION: A capacitive sensor 20 comprises: a plurality of electrodes 51-56; distribution lines 81-83 that are electrically connected to the electrodes 51-56; an insulation film 40 having flexibility; and coupling parts 41, 43, 45, 47 and 61 for coupling electrode film parts 40B-40G neighboring to each other in an X direction with each other at positions separated from a connection film part 40A of the insulation film 40 in a Y direction. The coupling parts 41, 43, 45, 47 and 61 include folding parts 41C, 43C, 45C, 47C and 61C that are foldable. By folding the folding parts 41C, 43C, 45C, 47C and 61C, a distance between the neighboring electrode film parts 40B-40G is adjusted into a predetermined distance and when integrating the capacitive sensor 20 into the rim, distances between the electrodes 51-56 are fixed in a rim extension direction E.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a grip detection device and a capacitance sensor, and more particularly to a grip detection device for detecting that a driver grips a rim of a steering wheel of an automobile and a capacitance sensor used therefor.

  Various sensors are mounted on the automobile, and various devices are controlled using signals detected by these sensors. For example, in order to control a car navigation system, a driving support system, a heater, an air bag, etc. depending on whether or not the driver is gripping the rim of the steering wheel, a capacitive sensor is incorporated in the rim. It is also detected whether or not the driver is holding the rim based on a change in capacitance between the electrode of the capacitance sensor and the driver's hand. Recently, a capacitance sensor that detects a grip state of a rim more accurately using a plurality of electrodes has also been developed (see, for example, FIG. 26 of Patent Document 1).

  FIG. 1 is a schematic diagram showing a conventional capacitance sensor incorporated in the rim of such a steering wheel. The capacitance sensor shown in FIG. 1 has a plurality of electrodes 501 to 506 extending along the direction in which the rim extends, and these electrodes 501 to 506 are arranged on a flexible insulating film 510. ing. Among these electrodes 501 to 506, the longest electrode 503 and the shortest electrode 506 extend linearly. In FIG. 1, the electrode 501 and the electrode 502 located on the left side of the electrode 503 are curved to the left side, and the electrode 504 and the electrode 505 located between the electrode 503 and the electrode 506 are curved to the right side. These electrodes 501 to 506 are connected to each other by a connection film portion 510 </ b> A of the insulating film 510.

  Since the longest electrode 503 is disposed on the outermost periphery of the rim and the shortest electrode 506 is disposed on the innermost periphery of the rim, these electrodes 503 and 506 are disposed along the direction in which the rim extends if formed in a straight line can do. On the other hand, the electrodes 501, 502, 504, and 505 must be arranged so that the distance between the adjacent electrodes is constant on the curved surface between the outermost and innermost rims, as shown in FIG. Thus, it is necessary to have a curved shape that matches the shape and size of the rim.

  When such a capacitance sensor is incorporated in the rim of the steering wheel, the electrodes 501 to 506 are attached along the rim. The electrodes 501 to 506 are portions to which the connection film portion 510A is connected. Since the electrodes 501 to 506 are connected to each other only at the positions, the electrodes 501 to 506 must be positioned independently at positions away from the connection film portion 510A. Thus, there is a problem that it is difficult to dispose the electrodes 501 to 506 at appropriate positions at positions away from the connection film portion 510A, and it is difficult to make the interval between adjacent electrodes constant. If the interval between adjacent electrodes is not constant, the detection of the grip state of the rim by the grip detection device will also be inaccurate.

International Publication No. 2014/123222

  The present invention has been made in view of such problems of the prior art, and it is a first object of the present invention to provide a capacitance sensor that can easily arrange a plurality of electrodes at appropriate positions when incorporated in a rim. The purpose.

  A second object of the present invention is to provide a grip detection device that can accurately detect the grip state of a rim.

  According to the first aspect of the present invention, it is possible to provide a capacitance sensor that can easily arrange a plurality of electrodes at appropriate positions when incorporated in a rim. This capacitance sensor is incorporated in the rim of the steering wheel. The capacitance sensor includes a plurality of electrodes, a wiring extending from each of the plurality of electrodes, and a flexible insulating film. The plurality of electrodes extend linearly along a first direction corresponding to a rim extending direction in which the rim extends, and are disposed on the outer periphery of the rim when incorporated in the rim. A straight electrode, a linear electrode extending linearly along the first direction, and disposed on the inner periphery of the rim when incorporated in the rim; And at least one curved electrode that extends along a first direction and is disposed between the outer periphery and the inner periphery of the rim when incorporated in the rim. The insulating film includes a plurality of electrode film portions on which the plurality of electrodes are placed, and a connection film portion that extends to intersect the first direction and connects the plurality of electrode film portions. This connection film part contains the said wiring inside. The capacitance sensor includes an electrode film portion adjacent in a second direction perpendicular to the first direction among the plurality of electrode film portions at a position spaced from the connection film portion in the first direction. It further has at least one connecting part connected to each other. The connecting portion has a foldable bending portion. The connecting portion adjusts the distance between the adjacent electrode film portions connected by the connecting portion by bending the bent portion to a predetermined distance, and the adjacent electrodes when incorporated in the rim. The distance between the electrodes placed on the film part is configured to be constant along the rim extending direction.

  With such a configuration, the distance between the electrode film portions can be adjusted to a predetermined distance by bending the bent portion of the connecting portion. It becomes easy to keep the distance between the electrodes placed on the electrode film portion constant along the rim extending direction. For this reason, it becomes easy to arrange | position an electrode in an appropriate position within a rim.

  The connecting portion may connect the end portions in the first direction of the adjacent electrode film portions to each other, or the end portion in the first direction of the adjacent electrode film portions and the connection. You may connect the said adjacent electrode film part mutually between film parts.

  The connecting portion may include a first base extending from one of the adjacent electrode film portions and a second base extending from the other of the adjacent electrode film portions. The bent portion of the connecting portion may be disposed between the first base portion and the second base portion. The connecting portion reduces the distance between the adjacent electrode film portions connected by the connecting portion by bending the bent portion so as to overlap one of the first base portion and the second base portion. It may be configured to. In this case, the bent portion of the connecting portion includes a boundary portion with the first base portion, a central portion between the first base portion and the second base portion, and the second base portion. You may be comprised so that it may bend in a boundary part, or you may be comprised so that it may bend in the boundary part with the said 1st base part and the boundary part with the said 2nd base part.

  The width of the bent portion in the direction perpendicular to the longitudinal direction of the connecting portion is preferably smaller than the width of the first base portion and the second base portion in the direction perpendicular to the longitudinal direction of the connecting portion. With such a configuration, the bent portion of the connecting portion becomes easier to bend than the first base portion and the second base portion, so that the operation of bending the bent portion is facilitated.

  The connecting portion may include a first base extending from one of the adjacent electrode film portions and a second base extending from the other of the adjacent electrode film portions. The bent portion of the connecting portion may be connected to an end portion of the first base portion and an end portion of the second base portion. The connecting portion expands the distance between the adjacent electrode film portions connected by the connecting portion by bending the bent portion so as to overlap both the first base portion and the second base portion. It may be configured to. In this case, the bent portion of the connecting portion may be configured to bend at a boundary portion between the first base portion and the end portion of the first base portion and a boundary portion between the second base portion and the end portion. Good.

  According to the second aspect of the present invention, a grip detection device capable of accurately detecting the grip state of the rim is provided. The grip detection device includes the above-described capacitance sensor and a grip detection unit connected to the wiring of the capacitance sensor. The capacitance sensor is attached to the rim of the steering wheel. The grip detection unit is configured to detect that the driver grips the rim based on a change in capacitance of the plurality of electrodes of the capacitance sensor.

  With such a configuration, the distance between the electrode film portions can be adjusted to a predetermined distance by bending the bent portion of the connecting portion. It becomes easy to keep the distance between the electrodes placed on the electrode film portion constant along the rim extending direction. For this reason, it becomes easy to arrange | position an electrode in an appropriate position in a rim | limb, and it becomes possible to detect the holding | grip state of a rim | limb more correctly.

  ADVANTAGE OF THE INVENTION According to this invention, when incorporating in a rim | limb, the electrostatic capacitance sensor which is easy to arrange | position a several electrode in an appropriate position is provided. Further, according to the present invention, a grip detection device capable of accurately detecting the grip state of the rim is provided.

It is a top view which shows the conventional electrostatic capacitance sensor with which the wheel core of a steering wheel is mounted | worn. It is a figure which shows typically the structure of the holding | grip detection apparatus in one Embodiment of this invention. It is a figure which shows typically the AA line cross section of FIG. It is a top view which shows the electrostatic capacitance sensor in the holding | grip detection apparatus shown in FIG. 2, and shows the state of the electrostatic capacitance sensor before incorporating in the rim | limb of a steering wheel. It is the BB sectional view taken on the line of FIG. It is CC sectional view taken on the line of FIG. It is the DD sectional view taken on the line of FIG. It is a figure which shows typically the circuit structure of the holding | grip detection apparatus shown in FIG. It is the elements on larger scale which show typically one connection part of the electrostatic capacitance sensor shown in FIG. It is the EE sectional view taken on the line of FIG. 7A. It is the elements on larger scale which show the process of bending the bending part of the connection part of FIG. 7A. It is sectional drawing of FIG. 8A. It is the elements on larger scale which show the process of bending the bending part of the connection part of FIG. 7A. It is sectional drawing of FIG. 9A. It is the elements on larger scale which show typically one connection part of the electrostatic capacitance sensor shown in FIG. It is a front view of FIG. 10A. It is the elements on larger scale which show the process of bending the bending part of the connection part of FIG. 10A. FIG. 11B is a front view of FIG. 11A. It is the elements on larger scale which show the process of bending the bending part of the connection part of FIG. 10A. It is a front view of Drawing 12A. It is the elements on larger scale which show the process of bending the bending part of the connection part of FIG. 10A. It is a front view of FIG. 13A. It is a top view which shows the electrostatic capacitance sensor in other embodiment of this invention. It is a top view which shows typically the connection part of the electrostatic capacitance sensor in other embodiment of this invention. It is a top view which shows typically the connection part of the electrostatic capacitance sensor in further another embodiment of this invention. It is a top view which shows typically the connection part of the electrostatic capacitance sensor in further another embodiment of this invention. It is the elements on larger scale which show the state which bent the bending part of the connection part shown in FIG. It is the FF sectional view taken on the line of FIG. 18A. It is a top view which shows typically the connection part of the electrostatic capacitance sensor in further another embodiment of this invention.

  Hereinafter, embodiments of the grip detection device according to the present invention will be described in detail with reference to FIGS. 2 to 19, the same or corresponding components are denoted by the same reference numerals, and redundant description is omitted. Further, in FIGS. 2 to 19, the scales and dimensions of the respective components are exaggerated and some components may be omitted.

  FIG. 2 is a diagram schematically showing the configuration of the grip detection device 1 according to an embodiment of the present invention. As shown in FIG. 2, the grip detection device 1 includes two capacitance sensors 20 and 20 incorporated in the rim 12 of the steering wheel 10, and a grip detection unit 22 disposed in the hub 14 of the steering wheel 10. In addition, wiring units 23 and 23 that electrically connect the capacitance sensors 20 and 20 and the grip detection unit 22 are provided. Each capacitance sensor 20 has a connection portion 21 connected to a wiring portion 23 extending from the grip detection portion 22 in the hub 14 through the inside of the spoke 15 of the steering wheel 10. The grip detection unit 22 determines whether or not the driver grips the rim 12 based on the change in capacitance detected by the capacitance sensors 20 and 20. In the present embodiment, the capacitance sensors 20, 20 are provided at two locations on the left and right sides of the rim 12, but the position and number of the capacitance sensors 20 are not limited to those illustrated. . For example, the number of capacitance sensors 20 may be one, or may be three or more.

  FIG. 3 is a diagram schematically showing a cross section taken along line AA of FIG. As shown in FIG. 3, the capacitance sensor 20 has six sensor portions 31 to 36 attached around the core 16 of the rim 12. These sensor units 31 to 36 are arranged apart from each other in the circumferential direction of the cross section of the core 16. On the outer peripheral surface of the capacitance sensor 20, a cushioning material 17 is provided for absorbing irregularities caused by the capacitance sensor 20 and preventing the irregularities on the surface of the rim 12. The outer peripheral surface of the cushioning material 17 is covered with a skin 18 made of leather or the like, and the driver operates the automobile by grasping the rim 12 from the skin 18.

  FIG. 4 is a plan view showing the capacitance sensor 20 before being incorporated into the rim 12. As shown in FIG. 4, the capacitance sensor 20 includes an insulating film 40 made of a flexible insulating material (for example, polyimide or polyethylene terephthalate (PET)). In FIG. 4, the Y direction corresponds to the direction E (see FIG. 2) in which the rim 12 (core 16) extends when the capacitance sensor 20 is attached to the outer peripheral surface of the core 16. This corresponds to the circumferential direction R (see FIG. 3) of the cross section of the core 16 perpendicular to the direction E. Hereinafter, a direction in which the rim 12 (core 16) extends may be referred to as a rim extending direction E, and a circumferential direction of a cross section of the core 16 may be referred to as a core cross-sectional circumferential direction R.

  As shown in FIG. 4, the six sensor units 31 to 36 described above are curved in the Y direction as a whole while being curved with the outer peripheral side linear sensor unit 31 and the inner peripheral side linear sensor unit 32 extending linearly along the Y direction. The first curve sensor unit 33, the second curve sensor unit 34, the third curve sensor unit 35, and the fourth curve sensor unit 36 are provided. These sensor units 31 to 36 are arranged to be separated from each other in the X direction, and as shown in FIG. It has become. Moreover, the sensor parts 31-36 are mutually connected by the connection film part 40A of the insulating film 40 in the approximate center of each Y direction. In the present embodiment, the connection film portion 40A extends in a direction (X direction) perpendicular to the direction in which the sensor portions 31 to 36 extend, but is not limited thereto, and the direction in which the sensor portions 31 to 36 extend. What is necessary is just to extend in the direction which crosses.

  The outer peripheral side linear sensor part 31 includes an outer peripheral side electrode film part 40B of the insulating film 40 extending linearly along the Y direction and an outer peripheral side linear electrode 51 extending linearly along the Y direction. The outer peripheral side linear electrode 51 is fixed on the outer peripheral side electrode film part 40B using a double-sided adhesive tape or an adhesive. The inner peripheral side linear sensor part 32 includes an inner peripheral side electrode film part 40C of the insulating film 40 extending linearly along the Y direction and an inner peripheral side linear electrode 52 extending linearly along the Y direction. Yes. The inner peripheral side linear electrode 52 is fixed on the inner peripheral side electrode film part 40C using a double-sided adhesive tape or an adhesive.

  When the electrostatic capacity sensor 20 is incorporated in the rim 12, the outer peripheral side linear sensor part 31 including the outer peripheral side linear electrode 51 is arranged along the rim extending direction E on the outermost periphery of the rim 12, and the inner peripheral side straight line The inner circumference side linear sensor part 32 including the electrode 52 is arranged along the rim extending direction E on the innermost circumference of the rim 12. For this reason, the length of the outer peripheral side linear electrode 51 in the Y direction is longer than the length of the inner peripheral side linear electrode 52 in the Y direction.

  The first bending sensor section 33 is located on the leftmost side in FIG. 4 and is curved to the left side with the first curved electrode film section 40D of the insulating film 40 that is curved to the left side and extends along the Y direction as a whole. However, the first curved electrode 53 extending along the Y direction as a whole is included. The first curved electrode 53 is fixed on the first curved electrode film portion 40D using a double-sided adhesive tape or an adhesive.

  The second curve sensor unit 34 is located between the first curve sensor unit 33 and the outer peripheral side linear sensor unit 31 in the X direction. The second curved sensor portion 34 is curved to the left and extends along the Y direction as a whole, and the second curved electrode film portion 40E of the insulating film 40 as a whole extends along the Y direction while curved to the left. A second curved electrode 54. Here, the degree of bending of the first bending electrode 53 is larger than the degree of bending of the second bending electrode 54. The 2nd curved electrode 54 is fixed on the 2nd curved electrode film part 40E using a double-sided adhesive tape or an adhesive material.

  The third curvature sensor unit 35 is located on the side opposite to the second curvature sensor unit 34 with respect to the outer peripheral side linear sensor unit 31. The third bending sensor portion 35 includes a third bending electrode film portion 40F of the insulating film 40 that extends in the Y direction as a whole while bending to the right side, and a third bending that extends in the Y direction as a whole while bending to the right side. And an electrode 55. The 3rd curved electrode 55 is fixed on the 3rd curved electrode film part 40F using a double-sided adhesive tape or an adhesive material.

  The fourth bending sensor unit 36 is located between the third bending sensor unit 35 and the inner circumferential linear sensor unit 32 in the X direction. The fourth bending sensor portion 36 includes a fourth curved electrode film portion 40G of the insulating film 40 that extends in the Y direction as a whole while bending to the right side, and a fourth curve that extends in the Y direction as a whole while bending to the right side. An electrode 56. Here, the degree of bending of the fourth bending electrode 56 is larger than the degree of bending of the third bending electrode 55. The 4th curved electrode 56 is fixed on the 4th curved electrode film part 40G using a double-sided adhesive tape or an adhesive material.

  5A is a sectional view taken along line BB in FIG. 4, FIG. 5B is a sectional view taken along line CC in FIG. 4, and FIG. 5C is a sectional view taken along line DD in FIG. As shown in FIGS. 4 and 5A to 5C, the capacitance sensor 20 of this embodiment includes a wiring unit 80 having three wirings 81 to 83 extending from the electrodes 51 to 56 in the X direction. These wirings 81 to 83 are formed in the connection film portion 40A of the insulating film 40 described above, as shown in FIGS. 5A to 5C.

  As shown in FIGS. 5A to 5C, the wirings 81 to 83 are formed below the electrodes 51 to 56. As shown in FIG. 5A, the wiring 81 is electrically connected to the first curved electrode 53 and the third curved electrode 55 via connection portions 84 and 84. Further, as shown in FIG. 5B, the wiring 82 is electrically connected to the outer peripheral side straight electrode 51 and the inner peripheral side straight electrode 52 through the connection portions 85 and 85. As shown in FIG. 5C, the wiring 83 is electrically connected to the second curved electrode 54 and the fourth curved electrode 56 via connection portions 86 and 86. The wirings 81 to 83, the connection portions 84 to 86, and the electrodes 51 to 56 are made of a conductive material such as silver or copper. Although not shown, each of the electrodes 51 to 56 is covered with an insulator such as a resist.

  The wirings 81 to 83 of the wiring unit 80 extend to the connection part 21 (see FIG. 2) of the capacitance sensor 20, where the wirings 81 to 83 extend from the grip detection unit 22 (see FIG. 2). By connecting to the terminal, the grip detection unit 22 and the electrodes 51 to 56 described above are electrically connected.

  FIG. 6 is a diagram schematically illustrating a circuit configuration of the grip detection device 1. As shown in FIGS. 5A to 5C and FIG. 6, the first curved electrode 53 and the third curved electrode 55 are connected to a common wiring 81, and the outer peripheral side straight electrode 51 and the inner peripheral side straight electrode 52 are common. Connected to the wiring 82, the second curved electrode 54 and the fourth curved electrode 56 are connected to a common wiring 83. In this way, the three electrodes adjacent along the circumferential direction R of the core cross section are connected to different wirings 81 to 83, respectively.

  As shown in FIG. 6, the grip detection unit 22 includes a C / V conversion circuit 91 connected to the first curved electrode 53 and the third curved electrode 55 via the wiring 81, and the outer peripheral side via the wiring 82. A C / V conversion circuit 92 connected to the straight electrode 51 and the inner peripheral side straight electrode 52, and a C / V conversion circuit 93 connected to the second curved electrode 54 and the fourth curved electrode 56 via the wiring 83. And detection circuits 94 to 96 connected to the C / V conversion circuits 91 to 93, respectively, and a determination unit 97 connected to the detection circuits 94 to 96.

  The C / V conversion circuits 91 to 93 use the connected electrodes as a part of the integration circuit, and generate a voltage pulse whose duty ratio changes depending on the capacitance value of the electrode, thereby converting the capacitance value into the voltage pulse. To convert. The detection circuits 94 to 96 detect the proximity or contact of the driver's hand to the rim 12 by converting the voltage pulse output from the C / V conversion circuits 91 to 93 into a direct current and comparing it with a predetermined threshold value. It is.

  The determination unit 97 determines the gripping state of the rim 12 of the steering wheel 10 based on the outputs from the detection circuits 94 to 96. For example, when one or two of the detection circuits 94 to 96 detect the proximity or contact of the hand, the determination unit 97 determines that the driver's hand has touched the rim 12, and all When the detection circuits 94 to 96 detect the proximity or contact of the hand, it is determined that the driver's hand has gripped the rim 12, and a control signal is sent to an external car navigation system, a driving support system, a heater, an airbag, or the like. Output. In this way, when all the detection circuits 94 to 96 detect the proximity or contact of the hand, it is determined that the driver's hand has gripped the rim 12, so that a soft arm or the like is straddled across the two electrodes. Further, it is possible to prevent erroneous detection that the driver's hand has gripped the rim 12.

  Returning to FIG. 4, the capacitance sensor 20 includes connecting portions 41 and 41 that connect the end portion in the Y direction of the outer peripheral side electrode film portion 40 </ b> B and the end portion in the Y direction of the second curved electrode film portion 40 </ b> E; The connecting portions 43 and 43 that connect the end portion in the Y direction of the outer peripheral side electrode film portion 40B and the end portion in the Y direction of the third curved electrode film portion 40F, and the Y direction of the first curved electrode film portion 40D Connecting portions 45, 45 for connecting the end portion of the second curved electrode film portion 40E to the end portion in the Y direction of the second curved electrode film portion 40E, and the end portion of the third curved electrode film portion 40F in the Y direction and the fourth curved electrode film. Connection portions 47 and 47 are provided for connecting the end portions of the portion 40G in the Y direction. These connecting portions 41, 43, 45, 47 may be formed integrally with the insulating film 40, or may be constituted by a member different from the insulating film 40. Since these connecting portions 41, 43, 45, 47 have substantially the same structure, the following description will be made centering on the connecting portion 41.

  7A is a partially enlarged view schematically showing the connecting portion 41 shown in FIG. 4, and FIG. 7B is a cross-sectional view taken along line EE of FIG. 7A. 7A and 7B, the longitudinal direction of the connecting portion 41 is the X ′ direction, and the direction perpendicular to the longitudinal direction of the connecting portion 41 is the Y ′ direction. As shown in FIGS. 7A and 7B, the connecting portion 41 includes a base portion 41A extending in the X ′ direction from an end portion in the Y direction of the outer peripheral side electrode film portion 40B, and an end in the Y direction of the second curved electrode film portion 40E. A base portion 41B extending in the X ′ direction from the portion, and a bent portion 41C that is disposed between the base portion 41A and the base portion 41B and connects them to each other. The distance between the end portion of the outer peripheral electrode film portion 40B and the end portion of the second curved electrode film portion 40E can be adjusted by bending the bent portion 41C as described below. In the present embodiment, the distance between the end portion in the Y direction of the outer peripheral side electrode film portion 40B in FIG. 4 and the end portion in the Y direction of the second curved electrode film portion 40E is the outer peripheral side electrode in the connecting film portion 40A. Since it is longer than the distance between the film part 40B and the 2nd curved electrode film part 40E, the edge part of the outer peripheral side electrode film part 40B and the edge of the 2nd curved electrode film part 40E are bent by bending the bending part 41C. The distance between the two portions is reduced to be equal to the distance between the outer peripheral electrode film portion 40B and the second curved electrode film portion 40E in the connection film portion 40A.

  Specifically, the boundary portion 42A between the bent portion 41C and the base portion 41A, the boundary portion 42B between the bent portion 41C and the base portion 41B, and the central portion 42C in the X ′ direction of the bent portion 41C are the bent portion 41C. For example, it is thin to make it easy to bend. In addition, in order to make it easy to bend the bending part 41C, you may form a groove | channel in these parts instead of making it thin. In such a connecting portion 41, when the boundary portion 42A and the boundary portion 42B are valley-folded, and the central portion 42C in the X ′ direction of the bent portion 41C is mountain-folded, the bent portion 41C is formed as shown in FIGS. 8A and 8B. Bends. When the center portion 42C in the X ′ direction of the bent portion 41C is completely bent and tilted to the base portion 41B side, as shown in FIGS. 9A and 9B, the bent portion 41C overlaps the base portion 41B and the base portion 41A of the bent portion 41C. And the distance between the base 41B is reduced.

Thus, in the present embodiment, by bending the bent portion 41C, the distance in the X ′ direction between the end portion of the outer peripheral electrode film portion 40B and the end portion of the second curved electrode film portion 40E is illustrated. It can be changed from D ₁ shown in 7A to D ₂ shown in FIG. 9A. Here, if the width in the X ′ direction of the bent portion 41C is W ₁ , D ₂ = D ₁ −W ₁ . This D ₂ is designed to be equal to the distance D _{3 in} the X direction (see FIG. 4) between the outer peripheral electrode film part 40B and the second curved electrode film part 40E in the connection film part 40A.

  In the present embodiment, as shown in FIG. 7A, the width of the bent portion 41C of the connecting portion 41 in the Y ′ direction is smaller than the width of the base portions 41A and 41B of the connecting portion 41 in the Y ′ direction. . Therefore, the bent portion 41C of the connecting portion 41 is easier to bend than the base portions 41A and 41B, and the operation of bending the bent portion 41C described above is easier.

Similarly, the connecting portion 43 that connects the end portion in the Y direction of the outer peripheral side electrode film portion 40B and the end portion in the Y direction of the third curved electrode film portion 40F is the end in the Y direction of the outer peripheral side electrode film portion 40B. A base portion 43A extending from the base portion, a base portion 43B extending from an end portion in the Y direction of the third curved electrode film portion 40F, and a bent portion 43C disposed between the base portion 43A and the base portion 43B and connecting them together. It is out. By bending the bent portion 43C in the same manner as the bent portion 41C of the connecting portion 41 described above, the distance between the end of the outer peripheral electrode film portion 40B and the end of the third curved electrode film portion 40F is increased. The distance can be reduced to a distance D ₄ (see FIG. 4) in the X direction between the outer peripheral electrode film part 40B and the third curved electrode film part 40F in the connection film part 40A. Thereby, the distance between the edge part of the outer peripheral side electrode film part 40B and the edge part of the 3rd curved electrode film part 40F is the outer peripheral side electrode film part 40B in the connection film part 40A, and the 3rd curved electrode film part 40F. Is equal to the distance between.

In addition, the connecting portion 45 that connects the end portion of the first curved electrode film portion 40D in the Y direction and the end portion of the second curved electrode film portion 40E in the Y direction is Y of the second curved electrode film portion 40E. 45A extending from the end portion in the direction, base portion 45B extending from the end portion in the Y direction of the first curved electrode film portion 40D, and the bent portion 45C that is disposed between the base portion 45A and the base portion 45B and connects them together. Including. By bending the bent portion 45C in the same manner as the bent portion 41C of the connecting portion 41 described above, the end portion of the first curved electrode film portion 40D in the Y direction and the end portion of the second bent electrode film portion 40E Can be reduced to a distance D ₅ (see FIG. 4) in the X direction between the first curved electrode film portion 40D and the second curved electrode film portion 40E in the connection film portion 40A. Thereby, the distance between the end portion of the first curved electrode film portion 40D and the end portion of the second curved electrode film portion 40E is equal to the first curved electrode film portion 40D and the second curved portion in the connection film portion 40A. It becomes equal to the distance between the electrode film portions 40E.

In addition, the connecting portion 47 that connects the end portion of the third curved electrode film portion 40F in the Y direction and the end portion of the fourth curved electrode film portion 40G in the Y direction is Y of the third curved electrode film portion 40F. 47A extending from the end portion in the direction, base portion 47B extending from the end portion in the Y direction of the fourth curved electrode film portion 40G, and a bent portion 47C that is arranged between the base portion 47A and the base portion 47B and connects them together. Including. By bending the bent portion 47C in the same manner as the bent portion 41C of the connecting portion 41 described above, a gap between the end portion of the third curved electrode film portion 40F and the end portion of the fourth curved electrode film portion 40G is obtained. The distance can be reduced to a distance D ₆ (see FIG. 4) in the X direction between the third curved electrode film portion 40F and the fourth curved electrode film portion 40G in the connection film portion 40A. Thereby, the distance between the end of the third curved electrode film part 40F and the end of the fourth curved electrode film part 40G is the same as that of the third curved electrode film part 40F and the fourth curve in the connection film part 40A. It becomes equal to the distance between the electrode film portions 40G.

  As shown in FIG. 4, the capacitance sensor 20 includes a connecting portion 61 that connects an end portion in the Y direction of the inner circumferential side electrode film portion 40C and an end portion in the Y direction of the fourth curved electrode film portion 40G, 61 is provided. The connecting portion 61 may be formed integrally with the insulating film 40 or may be constituted by a member different from the insulating film 40. FIG. 10A is a partially enlarged view schematically showing the connecting portion 61, and FIG. 10B is a front view of FIG. 10A. 10A and 10B, the connecting portion 61 shown in FIG. 4 is slightly rotated to define the X ″ direction and the Y ″ direction.

  As shown in FIGS. 10A and 10B, the connecting portion 61 includes a base portion 61A extending in the X ″ direction from an end portion in the Y direction of the inner peripheral side electrode film portion 40C, and a Y direction of the fourth curved electrode film portion 40G. A base portion 61B extending in the X ″ direction from the end portion of the base portion, and a bent portion 61C that connects the end portion of the base portion 61A and the end portion of the base portion 61B to each other. As shown in FIG. 10A, the connecting portion 61 is formed in a substantially Z shape. By bending the bent portion 61C as described below, the distance between the end portion of the inner peripheral side electrode film portion 40C and the end portion of the fourth curved electrode film portion 40G can be adjusted. . In the present embodiment, the distance between the end portion in the Y direction of the inner peripheral side electrode film portion 40C in FIG. 4 and the end portion in the Y direction of the fourth curved electrode film portion 40G is the inner periphery in the connection film portion 40A. Since the distance between the side electrode film part 40C and the fourth curved electrode film part 40G is shorter, the end part of the inner peripheral side electrode film part 40C and the fourth curved electrode film part are formed by bending the bent part 61C. The distance between the end portions of 40G is extended to be equal to the distance between the inner peripheral side electrode film portion 40C and the fourth curved electrode film portion 40G in the connection film portion 40A.

  Specifically, the boundary portion 62A between the bent portion 61C and the base portion 61A and the boundary portion 62B between the bent portion 61C and the base portion 61B are thin, for example, in order to easily bend the bent portion 61C. In addition, in order to make it easy to bend the bending part 61C, you may form a groove | channel in these parts instead of making it thin. In such a connecting portion 61, for example, when the boundary portion 62A is mountain-folded and the boundary portion 42B is valley-folded, as shown in FIGS. 11A and 11B, the end 63A of the bent portion 61C is centered on the boundary portion 62A. The end portion 63B of the bent portion 61C rotates about the boundary portion 62B. When the bent portion 61C is further bent, as shown in FIGS. 12A and 12B, the end portion 63A and the end portion 63B of the bent portion 61C further rotate, and finally, as shown in FIGS. 13A and 13B. As described above, the end portion 63A of the bent portion 61C overlaps the base portion 61A, and the end portion 63B of the bent portion 61C overlaps the base portion 61B.

Thus, in this embodiment, the distance between the edge part of the inner peripheral side electrode film part 40C and the edge part of the 4th curve electrode film part 40G is shown in FIG. 10A by bending the bending part 61C. It is possible to expand from D ₇ to D ₈ shown in FIG. 13A. This D ₈ is equal to the distance D ₉ (see FIG. 4) in the X direction between the inner peripheral electrode film part 40C and the fourth curved electrode film part 40G in the connection film part 40A.

  When incorporating the capacitance sensor 20 having such a configuration into the rim 12, first, the connection film portion 40A is fixed around the core 16 of the rim 12 using a double-sided adhesive tape or an adhesive. At this time, the connecting film portion 40 </ b> A is arranged so that the outer peripheral side straight electrode 51 is arranged on the outermost periphery of the core 16 of the rim 12 and the inner peripheral side straight electrode 52 is arranged on the innermost periphery of the core 16 of the rim 12. . And the outer peripheral side electrode film part 40B and the inner peripheral side electrode film part 40C are fixed to the outer peripheral surface and inner peripheral surface of the core 16 along the rim extending direction E.

  Next, the bending electrodes 53 to 56 are respectively fixed along the rim extending direction E between the outermost periphery and the innermost periphery of the core 16. Since these curved electrodes 53 to 56 are arranged on the curved surface between the outermost periphery and the innermost periphery of the core 16 along the rim extending direction E, the distance between adjacent electrodes is constant. Therefore, it must be fixed while adjusting the position according to the curved surface shape of the core 16.

  At this time, by bending the bent portion 41C of the connecting portion 41 as described above, the distance between the end portion of the outer peripheral side electrode film portion 40B and the end portion of the second curved electrode film portion 40E is connected film. It can be made equal to the distance between the outer peripheral electrode film part 40B and the second curved electrode film part 40E in the part 40A. Accordingly, the distance between the outer straight electrode 51 placed on the outer electrode film portion 40B and the second curved electrode 54 placed on the second curved electrode film portion 40E is set in the rim extending direction E. It becomes easy to make constant along. Similarly, by bending the bent portion 41C of the connecting portion 43, the bent portion 45C of the connecting portion 45, the bent portion 47C of the connecting portion 47, and the bent portion 61C of the connecting portion 61, the adjacent film portions Since the distance between the end portions can be made equal to the distance between the adjacent electrode film portions in the connection film portion 40A, the distance between the electrodes placed on these electrode film portions is along the rim extending direction E. It becomes easy to make it constant.

  In the above-described embodiment, the example in which the connecting portions 41, 43, 45, 47, 61 are provided at the end portions in the Y direction of the respective electrode film portions has been described. However, the positions at which such connecting portions are provided are the electrode film portions. It is not limited to the end portion in the Y direction. For example, as shown in FIG. 14, in addition to the connecting portions 41, 43, 45, 47, 61 described above, a similar connecting portion 141 is also provided between the end portion in the Y direction of the electrode film portion and the connecting film portion 40A. , 143, 145, 147, 161 may be provided. Further, the number of connecting portions is not limited to the illustrated one. Moreover, although not shown in figure, a connection part is provided only between the edge part of the Y direction of an electrode film part, and the connection film part 40A, without providing a connection part in the edge part of the Y direction of each electrode film part. Also good.

  In the above-described embodiment, as shown in FIG. 7A, the bent portion 41C of the connecting portion 41 is provided in the center in the Y ′ direction of the base portions 41A and 41B on both sides, but the connecting portion shown in FIG. As shown in FIG. 241, instead of the bent portion 41C, a bent portion 241C that linearly connects the end portion in the Y ′ direction of the base portion 41A and the end portion in the Y ′ direction of the base portion 41B along the X ′ direction. It may be provided. Or you may provide the bending part 341C which connects the edge part of Y 'direction of base 41A, and the edge part of Y' direction of base 41B diagonally like the connection part 341 shown in FIG. These structures can also be applied to the other connecting portions 43, 45, 47, 61, 141, 143, 145, and 147.

In the embodiment described above, in the connecting portion 41 shown in FIG. 7A, the boundary portion 42A between the bent portion 41C and the base portion 41A, the boundary portion 42B between the bent portion 41C and the base portion 41B, and the X of the bent portion 41C. 'Although the bent portion 41C is bent at the center portion 42C in the direction, other bending directions can be adopted. For example, as shown in FIG. 17, it may be bent only at the boundary portion 42A between the bent portion 41C and the base portion 41A and at the boundary portion 42B between the bent portion 41C and the base portion 41B. For example, when the boundary portion 42A is mountain-folded and the boundary portion 42B is valley-folded, the bent portion 41C can be bent as shown in FIGS. 18A and 18B. By bending the bent portion 41C in this way, the distance in the X ′ direction between the end portion of the outer peripheral electrode film portion 40B and the end portion of the second curved electrode film portion 40E is determined from D ₁ shown in FIG. 7A. It can be greatly reduced to D ₁₀ = D ₁ −2W ₁ shown in FIG. 18A. This bending method can also be applied to the other connecting portions 43, 45, 47, 61, 141, 143, 145, and 147.

  Moreover, you may change the magnitude | size of the edge parts 63A and 63B of the bending part 61C in the connection part 61 demonstrated by embodiment mentioned above. For example, as shown in FIG. 19, the end portions 63A and 63B of the bent portion 61C may be enlarged. In this way, compared to the case shown in FIG. 10A, the distance extended between the end portion of the inner peripheral side electrode film portion 40C and the end portion of the fourth curved electrode film portion 40G becomes larger.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and it goes without saying that the present invention may be implemented in various forms within the scope of the technical idea.

DESCRIPTION OF SYMBOLS 1 Grasp detection apparatus 10 Steering wheel 12 Rim 14 Hub 15 Spoke 16 Core 17 Buffer material 18 Skin 20 Capacitance sensor 21 Connection part 22 Grasp detection part 23 Wiring part 31 Outer peripheral side linear sensor part 32 Inner peripheral side linear sensor part 33 1st 1 bending sensor part 34 second bending sensor part 35 third bending sensor part 36 fourth bending sensor part 40 insulating film 40A connecting film part 40B outer peripheral side electrode film part 40C inner peripheral side electrode film part 40D first Curved electrode film part 40E Second curved electrode film part 40F Third curved electrode film part 40G Fourth curved electrode film part 41, 43, 45, 47 Connection part 41A, 41B, 43A, 43B, 45A, 45B, 47A 47B Base 41C, 43C, 45C, 47C Bent part 42A, 42 B boundary part 42C center part 51 outer peripheral side straight electrode 52 inner peripheral side straight electrode 53 first curved electrode 54 second curved electrode 55 third curved electrode 56 fourth curved electrode 61 connecting part 61A, 61B base 61C folding Curved part 63A, 63B End part 80 Wiring part 81-83 Wiring 84-86 Connection part 91-93 C / V conversion circuit 94-96 Detection circuit 97 Judgment part 141,143,145,147,161,241,341 Connection part 241C, 341C Bent part

Claims (11)

A capacitive sensor built into the rim of the steering wheel,
An outer peripheral side linear electrode extending linearly along a first direction corresponding to a rim extending direction in which the rim extends, and being disposed on an outer periphery of the rim when incorporated in the rim;
An inner circumferential linear electrode that extends linearly along the first direction and is disposed on the inner circumference of the rim when incorporated in the rim;
At least one curved electrode that extends along the first direction while being curved and is disposed between the outer periphery and the inner periphery of the rim when incorporated in the rim;
A plurality of electrodes including:
Wiring extending from each of the plurality of electrodes;
An insulating film having flexibility,
A plurality of electrode film portions on which the plurality of electrodes are placed;
A connection film portion extending so as to intersect the first direction and connecting the plurality of electrode film portions, the connection film portion including the wiring therein;
Including an insulating film;
At least one connection for connecting electrode film portions adjacent to each other in a second direction perpendicular to the first direction among the plurality of electrode film portions at a position spaced apart from the connection film portion in the first direction. At least one connecting part having a foldable folding part,
With
The connecting portion adjusts a distance between the adjacent electrode film portions connected by the connecting portion by bending the bent portion to a predetermined distance, and the adjacent electrodes when incorporated in the rim. The distance between the electrodes placed on the film part is configured to be constant along the rim extending direction,
A capacitance sensor.   2. The capacitance sensor according to claim 1, wherein the at least one connecting portion includes a connecting portion that connects end portions of the adjacent electrode film portions in the first direction to each other.   The at least one connecting portion includes a connecting portion that connects the adjacent electrode film portions to each other between the end portion in the first direction of the adjacent electrode film portions and the connection film portion. The capacitance sensor according to claim 2. The connecting portion includes a first base extending from one of the adjacent electrode film portions, and a second base extending from the other of the adjacent electrode film portions,
The bent portion of the connecting portion is disposed between the first base and the second base,
The connecting portion reduces the distance between the adjacent electrode film portions connected by the connecting portion by bending the bent portion so as to overlap one of the first base portion and the second base portion. It is comprised so that it may carry out. The electrostatic capacitance sensor as described in any one of Claim 1 to 3 characterized by the above-mentioned.   The bent portion of the connecting portion bends at a boundary portion with the first base portion, a central portion between the first base portion and the second base portion, and a boundary portion with the second base portion. The capacitance sensor according to claim 4, wherein the capacitance sensor is configured as described above.   5. The electrostatic device according to claim 4, wherein the bent portion of the connecting portion is configured to bend at a boundary portion with the first base portion and a boundary portion with the second base portion. Capacitance sensor.   The width of the bent portion in the direction perpendicular to the longitudinal direction of the connecting portion is smaller than the width of the first base portion and the second base portion in the direction perpendicular to the longitudinal direction of the connecting portion. The capacitance sensor according to any one of claims 4 to 6. The connecting portion includes a first base extending from one of the adjacent electrode film portions, and a second base extending from the other of the adjacent electrode film portions,
The bent portion of the connecting portion is connected to an end portion of the first base portion and an end portion of the second base portion,
The connecting portion expands the distance between the adjacent electrode film portions connected by the connecting portion by bending the bent portion so as to overlap both the first base portion and the second base portion. It is comprised so that it may carry out. The electrostatic capacitance sensor as described in any one of Claim 1 to 3 characterized by the above-mentioned.   The bent portion of the connecting portion is configured to bend at a boundary portion between the first base portion and the end portion of the first base portion and a boundary portion between the second base portion and the end portion. The capacitance sensor according to claim 8.   10. The capacitance sensor according to claim 1, wherein the at least one connecting portion is formed integrally with the insulating film. 11. The capacitance sensor according to any one of claims 1 to 10, which is mounted on a rim of a steering wheel,
A grip detection unit that is connected to the wiring of the capacitance sensor and detects that the driver grips the rim based on a change in capacitance in the plurality of electrodes of the capacitance sensor;
A gripping detection device comprising:

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