JP2017207463A - Pressure sensitive sensor and grasp detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure sensitive sensor which has a wide detection area with a simple configuration.SOLUTION: A pressure sensitive sensor 20A includes: a lower side substrate 22 which can be attached to a rim 12 of a steering wheel 10; an upper side substrate 26 disposed above the lower substrate 22; three pairs of electrodes 80A, 80B, and 80C; and a substrate spacer 24 around the pairs of electrodes 80A, 80B, and 80C. Each pair of electrodes 80A, 80B, and 80C consists of a lower side electrode 50 attached to an upper surface of the lower side substrate 22 and an upper electrode 60 attached to a lower surface of the upper side substrate 26 so as to face the lower side electrode 50. The upper side electrode 60 and the lower side electrode 50 are configured of pressure sensitive electrodes. The pressure sensitive sensor 20A includes: upper side common wiring 41 electrically connecting an upper side electrode 60B of the electrode pair 80B and an upper side electrode 60A of the electrode pair 80A to each other; and lower side common wiring 51 electrically connecting a lower side electrode 50B of the electrode pair 80B and a lower side electrode 50C of the electrode pair 80C to each other.SELECTED DRAWING: Figure 13

Description

  The present invention relates to a pressure sensor and a grip detection device, and more particularly to a grip detection device that detects that a driver grips a rim of a steering wheel of an automobile.

  Various sensors are mounted on the automobile, and various devices are controlled using signals detected by these sensors. For example, a car navigation system, a driving support system, a heater, an airbag, and the like are controlled depending on whether or not the driver is holding a rim of a steering wheel. Thus, in order to detect whether or not the driver has gripped the rim, a plurality of touch sensors are incorporated in the rim, and these touch sensors detect whether or not the driver's hand is in contact with the rim. (For example, refer to Patent Document 1).

  In order to more accurately detect the grip state of the rim, it is necessary to be able to detect the grip of the rim over a wide range. For this reason, in the technique disclosed in Patent Document 1, a plurality of touch sensors are arranged at equal intervals along the circumferential direction of the rim to widen the detection range. However, since these touch sensors independently determine contact or non-contact, there is a problem that wiring is required by the number of touch sensors, which complicates wiring and increases costs. .

  In order to more accurately detect the gripping state of the rim, it is preferable to detect contact or non-contact independently at a plurality of locations not only in the circumferential direction of the rim but also in the circumferential direction of the cross-section of the rim. In the technique disclosed in Patent Document 1, only one touch sensor is provided in the circumferential direction of the cross section of the rim. If a plurality of touch sensors are added in the circumferential direction of the cross section of the rim, the wiring complexity described above is increased. The problem of increasing costs and costs becomes even more pronounced.

JP 2014-061761 A

  The present invention has been made in view of the above-described problems of the prior art, and a first object thereof is to provide a pressure-sensitive sensor having a wide detection range with a simple circuit configuration.

  In addition, a second object of the present invention is to provide a grip detection device that can accurately detect that the driver grips the rim.

  According to the first aspect of the present invention, a pressure-sensitive sensor having a wide detection range with a simple circuit configuration is provided. This pressure sensor is incorporated in the rim of the steering wheel. The pressure-sensitive sensor is disposed around a lower substrate attachable to the rim, an upper substrate disposed above the lower substrate, at least three electrode pairs, and the at least three electrode pairs. A substrate spacer. Each of the at least three electrode pairs includes a lower electrode attached to the upper surface of the lower substrate and an upper electrode attached to the lower surface of the upper substrate so as to face the lower electrode. At least one of the upper electrode and the lower electrode is constituted by a pressure sensitive electrode. The substrate spacer is disposed between the upper substrate and the lower substrate. The pressure sensitive sensor includes the upper electrode in the electrode pair selected from the at least three electrode pairs, and one of the two electrode pairs arranged adjacent to both sides of the selected electrode pair. An upper common wiring that electrically connects the upper electrode of the pair, the lower electrode of the selected electrode pair, and the lower electrode of the other electrode pair of the two electrode pairs are electrically connected And a lower common wiring to be connected.

  As described above, since at least one of the upper electrode and the lower electrode is constituted by the pressure-sensitive electrode, the pressure (contact pressure) acting on the pressure-sensitive electrode is not simply detected by contact or non-contact between the electrodes. Detection based on this becomes possible. Therefore, it is possible to detect the grip state of the rim even if the area of each electrode is increased, and a wide detection range can be secured. Thus, since the area of each electrode can be increased, the total number of electrodes can be reduced. Accordingly, since the number of wirings is reduced, the circuit configuration of the sensor can be simplified and the cost can be reduced.

  In addition, since the pressure-sensitive sensor includes at least three electrode pairs, the contact pressure can be detected independently at a plurality of locations on the rim when the sensor is incorporated in the rim. Detection is possible. Further, the upper electrode of the selected electrode pair is electrically connected to the upper electrode of one of the two electrode pairs arranged adjacent to both sides of the selected electrode pair by the upper common wiring. The continuity is detected independently by electrically connecting the lower electrode of the selected electrode pair and the lower electrode of the other electrode pair of the two electrode pairs through the lower common wiring. Thus, the wiring system connected to the upper electrode and the lower electrode can be efficiently distributed to the upper substrate and the lower substrate. Therefore, the number of electrode pairs that can be arranged adjacent to each other can be increased. Thereby, since the location which can detect contact pressure increases, the detection of a more exact holding state is attained.

  The pressure sensor is at least one electrode spacer disposed on the inner side of the substrate spacer so that the lower electrode and the upper electrode facing each other are spaced apart from each other, and corresponds to a direction in which the rim extends. You may further provide at least 1 electrode spacer formed so that the length of 1 direction may become shorter than the length of the 2nd direction corresponding to the circumferential direction of a rim cross section perpendicular | vertical to the direction where the said rim extends. With such a configuration, even when a sensor whose electrode area is increased by using a pressure-sensitive electrode is curved along the circumferential direction of the rim cross section, the inner side of the substrate spacer provided around the pair of electrodes As a result of the interposition of the electrode spacer, the upper electrode and the lower electrode can be prevented from contacting each other unintentionally.

  According to the second aspect of the present invention, a pressure-sensitive sensor having a wide detection range with a simple circuit configuration is provided. This pressure sensor is incorporated in the rim of the steering wheel. The pressure sensor includes a first electrode unit and a second electrode unit adjacent to each other, and includes a plurality of electrode units connected in a first direction corresponding to the extending direction of the rim. . Each of the plurality of electrode units includes a lower substrate that can be attached to the rim, an upper substrate disposed above the lower substrate, at least three electrode pairs, and around the at least three electrode pairs. And a substrate spacer to be disposed. Each of the at least three electrode pairs includes a lower electrode attached to the upper surface of the lower substrate and an upper electrode attached to the lower surface of the upper substrate so as to face the lower electrode. At least one of the upper electrode and the lower electrode is constituted by a pressure sensitive electrode. The substrate spacer is disposed between the upper substrate and the lower substrate. The pressure sensitive sensor includes the upper electrode in the electrode pair selected from the at least three electrode pairs, and one of the two electrode pairs arranged adjacent to both sides of the selected electrode pair. An upper common wiring that electrically connects the upper electrode of the pair, the lower electrode of the selected electrode pair, and the lower electrode of the other electrode pair of the two electrode pairs are electrically connected And lower common wiring connected to. In this pressure-sensitive sensor, two upper electrodes to which the upper common wiring is electrically connected in the first electrode unit and one upper wiring that is not electrically connected to the second electrode unit are connected. The lower electrode is electrically connected to the upper electrode, the two lower electrodes to which the lower common wiring is electrically connected in the first electrode unit, and the lower electrode in the second electrode unit. One lower electrode to which the common wiring is not electrically connected is electrically connected.

  As described above, since at least one of the upper electrode and the lower electrode is constituted by the pressure-sensitive electrode, the pressure (contact pressure) acting on the pressure-sensitive electrode is not simply detected by contact or non-contact between the electrodes. Detection based on this becomes possible. Therefore, it is possible to detect the grip state of the rim even if the area of each electrode is increased, and a wide detection range can be secured. Thus, since the area of each electrode can be increased, the total number of electrodes can be reduced. Accordingly, since the number of wirings is reduced, the circuit configuration of the sensor can be simplified and the cost can be reduced.

  In addition, since the pressure-sensitive sensor includes at least three electrode pairs, the contact pressure can be detected independently at a plurality of locations on the rim when the sensor is incorporated in the rim. Detection is possible. Further, the upper electrode of the selected electrode pair is electrically connected to the upper electrode of one of the two electrode pairs arranged adjacent to both sides of the selected electrode pair by the upper common wiring. The continuity is detected independently by electrically connecting the lower electrode of the selected electrode pair and the lower electrode of the other electrode pair of the two electrode pairs through the lower common wiring. Thus, the wiring system connected to the upper electrode and the lower electrode can be efficiently distributed to the upper substrate and the lower substrate. Therefore, the number of electrode pairs that can be arranged adjacent to each other can be increased. Thereby, since the location which can detect contact pressure increases, the detection of a more exact holding state is attained.

  Further, of the first electrode unit and the second electrode unit adjacent to each other, the two upper electrodes to which the upper common wiring is electrically connected in the first electrode unit, and the second electrode unit In the electrode unit, the upper common wire that is not electrically connected to the one upper electrode is electrically connected, and in the first electrode unit, the lower common wire is electrically connected 2. The two lower electrodes are electrically connected to one lower electrode to which the lower common wiring is not electrically connected in the second electrode unit. With such a configuration, the first electrode unit and the second electrode unit are electrically connected to each other by the common wiring, and the conduction between the electrode pair of the first electrode unit and the second electrode unit is achieved. The continuity of the electrode pair can be detected independently. Accordingly, by arranging the pressure-sensitive sensor on the rim so that the boundary of the rim area is located between the first electrode unit and the second electrode unit, the area where the rim is gripped for each electrode pair. It is possible to detect the continuity of the electrode pair with a small amount of wiring.

  Here, at least one of the plurality of electrode units is at least one electrode spacer disposed inside the substrate spacer so that the lower electrode and the upper electrode facing each other are separated from each other, There may be further provided at least one electrode spacer formed so that the length in the first direction is shorter than the length in the second direction corresponding to the circumferential direction of the rim cross section perpendicular to the extending direction of the rim. . With such a configuration, even when a sensor whose electrode area is increased by using a pressure-sensitive electrode is curved along the circumferential direction of the rim cross section, the inner side of the substrate spacer provided around the pair of electrodes As a result of the interposition of the electrode spacer, the upper electrode and the lower electrode can be prevented from contacting each other unintentionally.

  The at least three electrode pairs are preferably arranged along a first direction corresponding to a circumferential direction of a rim cross section perpendicular to the extending direction of the rim. With such a configuration, the contact pressure can be detected independently at three or more locations along the circumferential direction of the cross section of the rim, and a more accurate gripping state can be detected.

  The number of the at least three electrode pairs is preferably an odd number. By setting the number of electrode pairs to an odd number, the effect of increasing the number of electrode pairs described above is further increased. Further, if the number of electrode pairs is an odd number, the same pattern can be used as the upper electrode pattern and the lower electrode pattern, so that the upper electrode and the lower electrode can be manufactured by the same manufacturing process. The manufacturing cost can be reduced.

  According to the second aspect of the present invention, there is provided a grip detection device that can accurately detect that the driver grips the rim. The grip detection device includes the above-described pressure-sensitive sensor incorporated in the rim of the steering wheel, and a grip detection unit that is electrically connected to the upper electrode and the lower electrode of the pressure sensor. The grip detection unit detects that the driver grips the rim based on a conduction state between the upper electrode of the pressure sensor and the lower electrode facing the upper electrode.

  Since the above-described sensor has a wide detection range, the grip detection device having such a configuration can detect the grip of the rim over a wide range, and can accurately detect that the driver has gripped the rim. Can be detected.

  The grip detection unit may include a detection circuit electrically connected to the upper electrode and the lower electrode in the at least three electrode pairs of the pressure sensor. The detection circuit may be configured to detect an electrical resistance formed between the upper electrode and the lower electrode of each of the at least three electrode pairs of the pressure sensor. The grip detection unit may include a determination unit that determines a grip state of the rim of the steering wheel based on an output from the detection circuit.

  When the determination unit of the grip detection unit determines that the electrical resistance of each of two adjacent electrode pairs among the at least three electrode pairs is lower than a predetermined threshold, the rim of the steering wheel It is preferable that it is comprised so that it may be judged that is hold | gripped. Such a configuration prevents erroneous detection that the rim is gripped when the driver accidentally touches a portion corresponding to any one electrode pair of the pressure sensor.

  According to the pressure-sensitive sensor of the present invention, since at least one of the upper electrode and the lower electrode is configured by the pressure-sensitive electrode, it acts on the pressure-sensitive electrode, not simply detection by contact or non-contact between the electrodes. Detection based on the pressing force (contact pressure) becomes possible. Therefore, it is possible to detect the grip state of the rim even if the area of each electrode is increased, and a wide detection range can be secured. Thus, since the area of each electrode can be increased, the total number of electrodes can be reduced. Accordingly, since the number of wirings is reduced, the circuit configuration of the sensor can be simplified and the cost can be reduced.

  In addition, since the pressure-sensitive sensor includes at least three electrode pairs, the contact pressure can be detected independently at a plurality of locations on the rim when the sensor is incorporated in the rim. Detection is possible. Further, the upper electrode of the selected electrode pair is electrically connected to the upper electrode of one of the two electrode pairs arranged adjacent to both sides of the selected electrode pair by the upper common wiring. The continuity is detected independently by electrically connecting the lower electrode of the selected electrode pair and the lower electrode of the other electrode pair of the two electrode pairs through the lower common wiring. Thus, the wiring system connected to the upper electrode and the lower electrode can be efficiently distributed to the upper substrate and the lower substrate. Therefore, the number of electrode pairs that can be arranged adjacent to each other can be increased. Thereby, since the location which can detect contact pressure increases, the detection of a more exact holding state is attained.

  According to the grip detection device of the present invention, since the pressure sensor described above is used, it is possible to detect grip of the rim in a wide range, and accurately detect that the driver grips the rim. Can do.

It is a figure which shows typically the structure of the holding | grip detection apparatus in the 1st 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 pressure sensor in the holding | grip detection apparatus shown in FIG. 1, and shows the state of the pressure sensor before incorporating in the rim | limb of a steering wheel. FIG. 4 is a bottom view of the pressure sensor shown in FIG. 3. FIG. 4 is a sectional view taken along line BB in FIG. 3. It is CC sectional view taken on the line of FIG. FIG. 6 is a plan view of the substrate spacer shown in FIG. 5. It is the DD sectional view taken on the line of FIG. It is the EE sectional view taken on the line of FIG. It is a figure which shows the state which attached the pressure sensor shown in FIG. 3 to the core of the rim | limb. FIG. 6 is a bottom view schematically showing an upper electrode and an upper wiring formed on the upper substrate of the pressure sensor shown in FIG. 5. FIG. 6 is a plan view schematically showing a lower electrode and a lower wiring formed on the lower substrate of the pressure sensitive sensor shown in FIG. 5. It is a figure which shows typically the circuit structure of the holding | grip detection apparatus shown in FIG. It is a figure which shows typically the circuit structure of the holding | grip detection apparatus shown in FIG. It is a figure which shows typically the circuit structure of the holding | grip detection apparatus shown in FIG. It is a figure which shows typically the circuit structure of the holding | grip detection apparatus shown in FIG. It is a figure which shows typically the circuit structure of the holding | grip detection apparatus shown in FIG. It is a figure which shows typically the wiring system different from the pressure sensor which concerns on the 1st Embodiment of this invention. It is a figure which shows typically the wiring system of the pressure sensor which concerns on the 1st Embodiment of this invention. It is a figure which shows typically the modification of the wiring system | strain of the pressure sensor which concerns on the 1st Embodiment of this invention. It is a figure which shows typically the other modification of the wiring system | strain of the pressure sensor which concerns on the 1st Embodiment of this invention. It is a figure which shows typically an example of the wiring system | strain in the pressure sensitive sensor which can distinguish and detect an area. It is a figure which shows typically the other example of the wiring system | strain in the pressure sensor which can distinguish and detect an area. It is a figure corresponding to FIG. 11 which shows the 2nd Embodiment of this invention. It is a figure corresponding to FIG. 12 which shows the 2nd Embodiment of this invention. It is a figure which shows typically the wiring system | strain of the pressure sensor which concerns on the 2nd Embodiment of this invention.

  Hereinafter, an embodiment of a grip detection device according to the present invention will be described in detail with reference to FIGS. In FIG. 1 to FIG. 26, the same or corresponding components are denoted by the same reference numerals, and redundant description is omitted. Further, in FIGS. 1 to 26, the scale and dimensions of each component are exaggerated, and some components may be omitted.

  FIG. 1 is a diagram schematically illustrating a configuration of a grip detection device 1 according to the first embodiment of the present invention. As shown in FIG. 1, the grip detection device 1 includes three pressure sensors 20 </ b> A, 20 </ b> B, and 20 </ b> C incorporated in the rim 12 of the steering wheel 10 and a grip detection unit 30 disposed in the hub 14 of the steering wheel 10. And a connection wiring portion 40 that electrically connects each of the pressure sensitive sensors 20A, 20B, and 20C and the grip detection unit 30. Each of the pressure sensitive sensors 20A, 20B, and 20C has connection portions 21A, 21B, and 21C that are connected to the connection wiring portion 40 that extends from the grip detection portion 30 in the hub 14 through the inside of the spoke 15 of the steering wheel 10. doing.

  The pressure sensor 20A is provided from the left region H to the upper region J of the rim 12, and the pressure sensor 20B is provided from the right region M to the upper region J of the rim 12, and pressure sensitive. The sensor 20 </ b> C is provided in a portion of the region K below the rim 12. Hereinafter, the pressure sensor 20A among the three pressure sensors 20A, 20B, and 20C will be mainly described. However, the configuration of the other pressure sensors 20B and 20C is the same as the configuration of the pressure sensor 20A described below. It is. The positions and number of the pressure sensitive sensors 20A, 20B, and 20C are not limited to those shown in the drawing. For example, the number of pressure sensors may be one, two, or four or more.

  FIG. 2 is a diagram schematically showing a cross section taken along line AA of FIG. The upper side in FIG. 2 shows the front side of the rim 12 (the front side of the paper surface in FIG. 1), and the lower side shows the back side of the rim 12 (the back side of the paper surface in FIG. 1). As shown in FIG. 2, a cushion material 300 is provided around the outer peripheral surface of the core 16 of the rim 12. The pressure-sensitive sensor 20A is mounted on such a cushioning material 300 so as to cover substantially the entire outer peripheral surface of the cross section of the core 16 of the rim 12. In addition, you may comprise such a cushioning material 300 with urethane etc., for example.

  A buffer material 17 is provided on the outer peripheral surface of the pressure-sensitive sensor 20 </ b> A so as to absorb unevenness caused by the pressure-sensitive sensor 20 </ b> A and prevent the unevenness 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.

  As shown in FIG. 2, the pressure-sensitive sensor 20 </ b> A includes a lower substrate 22 attached on the cushioning material 300, a substrate spacer 24 fixed on the lower substrate 22, and an upper side fixed on the substrate spacer 24. The substrate 26, a plurality of lower electrodes 50 attached to the upper surface of the lower substrate 22, a plurality of upper electrodes 60 attached to the lower surface of the upper substrate 26, and the lower electrode 50 and the upper electrode 60 facing each other And at least one electrode spacer 90 disposed therebetween. In the present embodiment, the lower electrode 50 and the upper electrode 60 facing each other are separated from each other by an electrode spacer 90, and the lower electrode 50 and the upper electrode 60 constitute one electrode pair 80.

  FIG. 3 is a plan view showing the pressure-sensitive sensor 20A before being incorporated into the rim 12, and FIG. 4 is a bottom view. 5 is a cross-sectional view taken along line BB in FIG. 3, and FIG. 6 is a cross-sectional view taken along line CC in FIG. As shown in FIGS. 3 and 4, the upper substrate 26 and the lower substrate 22 have the same outer shape and are formed of a flexible resin such as polyimide or polyethylene terephthalate (PET). . 3 and 4, the Y direction (first direction) corresponds to the direction E (see FIG. 1) in which the rim 12 (core 16) extends, and the X direction (second direction) is pressure sensitive. This corresponds to the circumferential direction R (see FIG. 2) of the rim cross section (cross section of the core 16) perpendicular to the direction in which the rim 12 extends when the sensor 20A is attached to the outer peripheral surface of the core 16. Hereinafter, the direction in which the rim 12 (core 16) extends may be referred to as a rim extending direction E, and the circumferential direction of the rim section may be referred to as a rim section circumferential direction R.

  As shown in FIG. 3, the upper substrate 26 is made of a substantially rectangular plate material that is long in the Y direction, and notches 70 are formed on both sides in the X direction at predetermined intervals along the Y direction. By forming such a notch 70, the upper substrate 26 has a structure in which a plurality of substantially strip-shaped substrate pieces 26A are connected in the Y direction. Similarly, as shown in FIG. 4, the lower substrate 22 is made of a substantially rectangular plate material that is long in the Y direction, and notches 71 are formed on both sides in the X direction at predetermined intervals along the Y direction. Has been. By forming such a notch 71, the lower substrate 22 has a structure in which a plurality of substantially strip-shaped substrate pieces 22A are connected in the Y direction.

  As shown in FIGS. 5 and 6, a substrate spacer 24 is disposed between the upper substrate 26 and the lower substrate 22. Here, FIG. 7 is a plan view of the substrate spacer 24. As shown in FIG. 7, the substrate spacer 24 has substantially the same outer shape as the upper substrate 26 and the lower substrate 22, and is formed of a flexible resin such as polyimide or polyethylene terephthalate (PET). Can be done. The substrate spacer 24 is made of a substantially rectangular plate material that is long in the Y direction, and notches 72 are formed on both sides in the X direction at predetermined intervals along the Y direction. By forming such a notch 72, the substrate spacer 24 has a structure in which a plurality of substantially strip-shaped substrate spacer pieces 24A are connected in the Y direction.

  Thus, the pressure-sensitive sensor 20A has a laminated structure in which the lower substrate 22, the substrate spacer 24, and the upper substrate 26, which have substantially the same outer shape, overlap each other. That is, it has a laminated structure in which the substrate spacer 24 is disposed on the lower substrate 22 and the upper substrate 26 is disposed on the substrate spacer 24 (see FIG. 5). Here, one substrate piece 22A of the lower substrate 22, a substrate spacer piece 24A disposed thereon, a lower electrode 50 formed on the substrate piece 22A, and an upper portion disposed on the substrate spacer piece 24A. A substrate piece 26A of the substrate 26, an upper electrode 60 formed on the substrate piece 26A, and an electrode spacer 90 disposed between the lower electrode 50 and the upper electrode 60 are grouped into an electrode unit 75 (FIG. 3). (See FIG. 6). In this embodiment, each electrode unit 75 has three electrode pairs 80 arranged along the X direction, and two electrode spacers 90 are arranged for each electrode pair 80 (FIG. 5). And FIG. 6). That is, the electrode unit 75 in the present embodiment includes six electrode spacers 90 in total. The pressure-sensitive sensor 20A has a structure in which a plurality of such electrode units 75 (15 in this embodiment) are connected in the Y direction (see FIGS. 3 and 4).

  In this embodiment, the electrode unit 75 includes three electrode pairs 80 (see FIG. 5). However, the present invention is not limited to this, and the electrode unit 75 may include four or more electrode pairs. Good. In this embodiment, the pressure sensor 20A has a structure in which 15 electrode units 75 are connected in the Y direction (see FIGS. 3 and 4), but the number of electrode units can be changed as appropriate. Not too long.

  Here, as shown in FIG. 7, each substrate spacer piece 24A of the substrate spacer 24 has three through holes 25, 25 corresponding to the upper electrode 60 and the lower electrode 50 along the X direction. Are formed at intervals. In the present embodiment, three through holes 25 are formed in the substrate spacer piece 24 </ b> A corresponding to the three electrode pairs 80 constituting the electrode unit 75. The number of through holes 25 may be changed according to the number of pairs.

  Referring again to FIGS. 5 and 6, the upper electrode 60 and the lower electrode 50 (that is, the electrode pair 80) facing each other are positioned in the through hole 25 of the substrate spacer 24. That is, the substrate spacers 24 are located on both sides of each electrode pair 80 in the X direction. In this embodiment, the substrate spacer 24 is arranged so as to surround the electrode pair 80. The lower substrate 22 and the upper substrate 26 constituting each electrode unit 75 are separated from each other by the substrate spacer 24. Thus, the pressure sensitivity is maintained while the lower substrate 22 and the upper substrate 26 are separated from each other. The sensor 20 </ b> A can be attached to the outer peripheral surface of the core 16.

  In the electrode unit 75 in FIG. 5, three electrode pairs 80 are formed along the X direction. Here, the upper electrode 60 and the lower electrode 50 constituting each electrode pair 80 have dimensions slightly smaller than the through-hole 25 and have substantially the same rectangular outer shape. With such a configuration, the lower electrode 50 and the upper electrode 60 forming the electrode pair 80 are entirely opposed to each other. The substrate spacer 24 may be disposed between the lower substrate 22 and the upper substrate 26 so that the lower substrate 22 and the upper substrate 26 constituting the electrode unit 75 are separated from each other. The upper electrode 60 and the lower electrode 50 that are configured may be slightly larger than the through-hole 25, and the substrate spacer 24 may be disposed so as to surround the periphery (periphery) of the upper electrode 60 and the lower electrode 50. .

  8 is a cross-sectional view taken along line DD in FIG. 5, and FIG. 9 is a cross-sectional view taken along line EE in FIG. As shown in FIGS. 8 and 9, the upper electrode 60 and the lower electrode 50 have the same outer shape that is substantially rectangular, and face each other as described above. The upper electrode 60 and the lower electrode 50 are surrounded by the substrate spacer 24. Therefore, when the pressure sensitive sensor 20A is attached to the outer peripheral surface of the core 16, the substrate spacers 24 are located on both sides of the rim cross-section circumferential direction R and both sides of the rim extending direction E of each electrode pair 80. Become. With such a configuration, the pressure-sensitive sensor 20A is attached to the outer peripheral surface of the core 16 with the lower substrate 22 and the upper substrate 26 separated from each other (see FIG. 2).

  Further, as shown in FIGS. 8 and 9, inside the substrate spacer 24 that surrounds the periphery of the electrode pair 80, the electrode pair 80 is located near the center in the Y direction (on both sides of the center). Two elongated electrode spacers 90 extending in the direction are arranged. That is, between the lower electrode 50 and the upper electrode 60 facing each other, two elongated electrode spacers 90 extending in the X direction are disposed in the vicinity of the center of the electrode pair 80 in the Y direction. Each electrode spacer 90 is configured as a generally linear spacer whose width in the Y direction is extremely short compared to the length in the X direction. Such an electrode spacer 90 extends from one end of the electrode pair 80 in the X direction to the other end, and connects the upper surface 501 of the lower electrode 50 and the lower surface 601 of the upper electrode 60 ( (See FIG. 6). With such a configuration, the lower electrode 50 and the upper electrode 60 that form the electrode pair 80 are separated from each other, and the lower electrode 50 and the upper electrode are mounted even when the pressure-sensitive sensor 20A is attached to the outer peripheral surface of the core 16. The state where 60 is separated from each other is maintained (see FIG. 2). Such an electrode spacer 90 may be formed of a flexible material such as silicon rubber.

  FIG. 10 is a plan view showing a state in which the pressure-sensitive sensor 20A is attached to the core 16 of the rim 12, and shows a state before the pressure-sensitive sensor 20A is covered with the skin 18 (see FIG. 2). As shown in FIG. 10, the pressure sensor 20 </ b> A is attached so that the center in the X direction of the pressure sensor 20 </ b> A is along the outer periphery of the annular portion of the core 16 (along the rim extending direction E). Here, as described above, since the notches 70, 71, 72 are formed between the electrode units 75 adjacent to each other, the rim extending direction E when the pressure-sensitive sensor 20A is attached to the outer peripheral surface of the core 16. It is possible to prevent the electrode units 75 adjacent to each other from overlapping, and to increase the area where the pressure-sensitive sensor 20A covers the outer peripheral surface of the core 16.

  Here, the lower electrode 50 and the upper electrode 60 in the present embodiment are configured as pressure-sensitive electrodes whose resistance value changes depending on the pressing force. For example, silver is coated with a pressure-sensitive material such as carbon. It is formed. Unlike a contact-type sensor that detects only whether or not two opposing electrodes are in contact with each other, such a pressure-sensitive electrode can detect a force pressed by a change in resistance value. By increasing the area, the detection range can be expanded.

  2 and 10, when the pressure sensor 20A is attached to the rim 12, the pressure sensor 20A is greatly curved along the circumferential direction R of the rim cross section (that is, the Z direction shown in FIG. 5). Therefore, if the area of the lower electrode 50 and the upper electrode 60 constituting each electrode pair 80 is to be increased, the upper electrode 60 is not attached to the rim 12 when the pressure sensor 20A is attached to the rim 12. It is conceivable that the lower electrode 50 is bent and contacts. In such a state, even when the driver is not gripping the rim 12, the electrode pair 80 is always in a conductive state, so that the grip detection unit 30 cannot accurately detect the grip. In the present embodiment, as shown in FIGS. 8 and 9, the above-described electrode spacer 90 is disposed between the lower electrode 50 and the upper electrode 60 of the electrode pair 80, whereby the upper electrode 60 and the lower electrode 50. Even when the area is increased, the upper electrode 60 and the lower electrode 50 are prevented from unintentionally contacting when the pressure-sensitive sensor 20A is attached to the rim 12 (see FIG. 2). In the present embodiment, two electrode spacers 90 are provided for one electrode pair 80, but the number of electrode spacers 90 for one electrode pair 80 is not limited to this.

  Further, as described above, the cushion material 300 (see FIG. 2) is disposed between the lower substrate 22 and the core 16 of the rim 12. With such a configuration, even when the electrode pair 80 is pressed from above in order to curve the pressure-sensitive sensor 20A, this pressing can be absorbed by the cushion material 300. Therefore, the lower electrode 50 and the upper electrode 60 of the electrode pair 80 can be more effectively prevented from contacting each other unintentionally. Even when the cushion material 300 is not provided, it is possible to prevent the lower electrode 50 and the upper electrode 60 from contacting each other as will be described later.

  That is, in the present embodiment, the lower electrode 50 and the upper electrode 60 of the electrode pair 80 are not in contact with each other simply by being attached to the rim 12, and are directed from the outside of the upper substrate 26 toward the lower substrate 22. Only when the force is applied and the upper substrate 26 and the electrode spacer 90 are bent toward the core 16, the upper electrode 60 of the portion comes into contact with the lower electrode 50. Therefore, the areas of the upper electrode 60 and the lower electrode 50 can be increased, the detection range can be widened, and the number of electrodes can be reduced to simplify the wiring.

  FIG. 11 is a bottom view schematically showing the upper substrate 26 together with the upper electrode 60 and the wiring. As shown in FIG. 11, when the upper electrode 60 in this embodiment is incorporated in the rim 12, five upper electrodes 60AJ arranged on the front side of the region J (see FIG. 1) on the upper side of the rim 12, Five upper electrodes 60BJ disposed on the outer peripheral side of the region J, five upper electrodes 60CJ disposed on the back side of the region J, and 10 disposed on the front side of the region H on the left side of the rim 12 (see FIG. 1). Each of the upper electrodes 60AH, ten upper electrodes 60BH disposed on the outer peripheral side of the region H, and ten upper electrodes 60CH disposed on the back side of the region H are included.

  In addition to these upper electrodes 60, wirings 41 to 47 that are electrically connected to the upper electrode 60 are formed on the upper substrate 26. In the present embodiment, the upper electrodes 60AJ, 60AH arranged on the front side of the rim 12 and the upper electrodes 60BJ, 60BH arranged on the outer peripheral side of the rim 12 are connected to each other by the wiring 41. Further, the upper electrode 60BJ disposed on the outer peripheral side of the region J of the rim 12 and the five upper electrodes 60BH disposed on the outer peripheral upper side of the region H are connected to each other by the wiring 42. The upper electrodes 60AJ and 60BJ in the region J and the upper electrodes 60AH and 60BH in the upper portion of the region H are connected to the terminal T1 provided in the connection portion 21A via the wiring 43. The five upper electrodes 60 </ b> BH disposed on the lower outer periphery of the region H of the rim 12 are also connected to each other by the wiring 44. Upper electrodes 60AH and 60BH on the lower side of the region H are connected to a terminal T2 provided in the connection portion 21A via a wiring 45. The upper electrodes 60CJ and 60CH disposed on the back side of the rim 12 are connected to each other by a wiring 46 and are connected to a terminal T3 provided in the connection portion 21A through a wiring 47. By connecting these terminals T <b> 1 to T <b> 3 to the terminals of the connection wiring portion 40 (see FIG. 1) extending from the grip detection unit 30, the grip detection unit 30 and the upper electrode 60 are electrically connected.

  FIG. 12 is a plan view schematically showing the lower substrate 22 together with the lower electrode 50 and the wiring. As shown in FIG. 12, when the lower electrode 50 in this embodiment is incorporated in the rim 12, five lower electrodes 50AJ are arranged on the front side of the region J (see FIG. 1) above the rim 12. And five lower electrodes 50BJ disposed on the outer peripheral side of the region J, five lower electrodes 50CJ disposed on the front side of the region J, and the region H on the left side of the rim 12 (see FIG. 1) 10 lower electrodes 50AH arranged, 10 lower electrodes 50BH arranged on the outer peripheral side of the region H, and 10 lower electrodes 50CH arranged on the back side of the region H are included. .

  In addition to the lower electrode 50, wirings 51 to 57 that are electrically connected to the lower electrode 50 are formed on the lower substrate 22. In the present embodiment, the lower electrodes 50CJ, 50CH disposed on the back side of the rim 12 and the lower electrodes 50BJ, 50BH disposed on the outer peripheral side of the rim 12 are connected to each other by the wiring 51. The lower electrodes 50BJ and 50BH arranged on the outer peripheral side of the rim 12 are connected to each other by a wiring 52. The lower electrodes 50BJ, 50CJ, 50BH, and 50CH are connected to a terminal T4 provided in the connection portion 21A via a wiring 53. The lower electrode 50AJ arranged on the front side of the region J of the rim 12 and the five lower electrodes 50AH arranged on the upper side of the region H are connected to each other by the wiring 54. The lower electrode 50AJ of the region J and the lower electrode 50AH above the region H are connected to a terminal T5 provided in the connection portion 21A via the wiring 55. Further, the five lower electrodes 50AH arranged on the lower side of the front side of the rim region H are also connected to each other by the wiring 56, and are connected to the terminal T6 provided in the connecting portion 21A through the wiring 57. These terminals T4 to T6 are connected to the terminals of the connection wiring part 40 (see FIG. 1) extending from the grip detection part 30, whereby the grip detection part 30 and the lower electrode 50 are electrically connected.

  13 to 17 are diagrams schematically illustrating a circuit configuration of the grip detection device 1. In FIG. 13 to FIG. 17, for ease of understanding, only the wiring for one electrode unit 75 of the plurality of electrode units 75 arranged in the region J of the rim 12 is illustrated, and the other electrode units are illustrated. The wiring is not shown. As shown in FIGS. 13 to 17, the grip detection unit 30 corresponds to a detection circuit 32 </ b> A corresponding to the electrode pair 80 </ b> A disposed on the front side of the rim 12 and an electrode pair 80 </ b> B disposed on the outer peripheral side of the rim 12. Based on the detection circuit 32B, the detection circuit 32C corresponding to the electrode pair 80C disposed on the back side of the rim 12, and the output from the detection circuits 32A, 32B, 32C, the gripping state of the rim 12 of the steering wheel 10 is determined. And a determination unit 34. When the driver grips the rim 12, both the front side and the back side of the rim 12 are often pressed. Therefore, the electrode pairs 80 </ b> A and 80 </ b> C are arranged on the front side and the back side of the rim 12 as in this embodiment. Thus, the gripping state of the rim 12 can be detected more accurately. The determination unit 34 includes a processor such as a CPU and a memory associated therewith.

  As described with reference to FIG. 11, the upper electrode 60B disposed on the outer peripheral side of the rim 12 and the upper electrode 60A disposed on the front side of the rim 12 are connected to each other by the wiring 41 (upper common wiring). . Further, as described with reference to FIG. 12, the lower electrode 50B facing the upper electrode 60B and the lower electrode 50C disposed on the back side of the rim 12 are connected to each other by the wiring 51 (lower common wiring). ing.

As shown in FIG. 13, the detection circuit 32A is connected between the upper electrode 60A and the lower electrode 50A arranged on the front side of the rim 12, and the voltage between the upper electrode 60A and the lower electrode 50A. V _A is measured, and an electric resistance formed between the upper electrode 60A and the lower electrode 50A is detected based on the voltage V _A. The detection circuit 32B is connected between the upper electrode 60B and the lower electrode 50B disposed on the outer peripheral side of the rim 12, and measures the voltage V _B between the upper electrode 60B and the lower electrode 50B. Based on this voltage V _B , an electrical resistance formed between the upper electrode 60B and the lower electrode 50B is detected. The detection circuit 32C is connected between the upper electrode 60C and the lower electrode 50C disposed on the back side of the rim 12, and measures the voltage V _C between the upper electrode 60C and the lower electrode 50C. The electrical resistance formed between the upper electrode 60C and the lower electrode 50C is detected based on the voltage V _C. In the present embodiment, the lower electrodes 50A, 50B, and 50C and the upper electrodes 60A, 60B, and 60C are configured as pressure-sensitive electrodes whose resistance values change depending on the pressing force, and thus the upper electrodes 60A, 60B, By detecting the respective electrical resistances formed between 60C and the lower electrodes 50A, 50B, 50C, the contact pressure to the pressure sensor 20A can be detected.

  When the driver grips the rim 12 of the steering wheel 10, the gripping force causes the gripped portion of the upper substrate 26 to be pushed toward the core 16 and bend. Along with this, the upper electrode 60 of the electrode pair 80 in that portion comes into contact with the lower electrode 50 and the electrode pair 80 becomes conductive, and the voltage (or current) changes due to the change of the resistance value according to the contact pressure. It will be. The detection circuits 32 </ b> A, 32 </ b> B, and 32 </ b> C detect changes in voltage (or current) and electric resistance value in the electrode pair 80 caused by gripping the rim 12. The outputs of the detection circuits 32A, 32B, and 32C are input to the determination unit 34. The determination unit 34 determines whether the driver is holding the rim 12 according to the output from the detection circuits 32A, 32B, and 32C. .

  At this time, the determination unit 34 can determine the gripping state of the rim 12 according to an arbitrary standard. For example, when a voltage exceeding a predetermined threshold is detected by one or more detection circuits, it may be determined that the gripping state is present, or when a voltage exceeding a predetermined threshold is detected by a plurality of detection circuits. It may be determined that the user is in the gripping state, or may be determined to be in the gripping state when a voltage exceeding a predetermined threshold is detected by a plurality of detection circuits having a specific positional relationship. A standard can be set. The determination unit 34 in the present embodiment is in the gripping state when a voltage exceeding a predetermined threshold is detected in the detection circuits 32A, 32B, and 32C corresponding to two electrode pairs adjacent to each other among the electrode pairs 80A, 80B, and 80C. It shall be judged that That is, when the voltage exceeding a predetermined threshold is detected by both the detection circuit 32A and the detection circuit 32B, or the voltage exceeding the predetermined threshold is detected by both the detection circuit 32B and the detection circuit 32C, the determination unit 34 Is determined to be in a gripping state.

FIG. 13 shows a state where the driver is not gripping the rim 12 of the steering wheel 10. In this state, since all of the upper electrodes 60A, 60B, and 60C are separated from the lower electrodes 50A, 50B, and 50C, the voltages V _A , V _B , and V _C measured by the detection circuits 32A, 32B, and 32C are It does not change.

FIG. 14 shows a state in which the driver's hand is in contact with the front side of the rim 12 of the steering wheel 10. In this state, the upper electrode 60A of the electrode pair 80A is in contact with the lower electrode 50A. As the contact pressure of the electrode pair 80A increases, the electrical resistance value between the upper electrode 60A and the lower electrode 50A decreases, and the voltage V _A measured by the detection circuit 32A of the grip detection unit 30 increases. At this time, in the electrode pair 80B adjacent to the electrode pair 80A, the upper electrode 60B and the lower electrode 50B are not in contact with each other, and the increase in the voltage V _B is not detected in the detection circuit 32B corresponding to the electrode pair 80B. In this case, since the determination condition of the grip state that “a voltage exceeding a predetermined threshold is detected in the detection circuits 32A, 32B, and 32C corresponding to the two electrode pairs 80A, 80B, and 80C adjacent to each other” is not satisfied, The determination unit 34 determines that the driver is not gripping the rim 12.

FIG. 15 shows a state where the driver holds the rim 12 of the steering wheel 10. In this state, the upper electrodes 60A and 60B of the electrode pairs 80A and 80B are in contact with the lower electrodes 50A and 50B, respectively. In this case, the voltages V _A and V _B measured by the detection circuits 32A and 32B increase as the contact pressure of the electrode pairs 80A and 80B increases. When the voltages V _A and V _B thus increased exceed a predetermined threshold, “a voltage exceeding the predetermined threshold is detected in the detection circuits 32A and 32B corresponding to the two electrode pairs 80A and 80B adjacent to each other”. Therefore, the determination unit 34 determines that the driver is gripping the rim 12, and installs it in an external car navigation system, a driving support system, a heater, an airbag, or the like. Output a control signal.

  16 and 17 show another state in which the driver grips the rim 12 of the steering wheel 10. In the state shown in FIG. 16, a voltage exceeding a predetermined threshold is detected in the detection circuits 32B and 32C corresponding to the two electrode pairs 80B and 80C adjacent to each other. Also in this case, the gripping state determination condition that “a voltage exceeding a predetermined threshold is detected in the detection circuits 32B and 32C corresponding to the two electrode pairs 80B and 80C adjacent to each other” is satisfied. The determination unit 34 determines that the driver is holding the rim 12. In the state shown in FIG. 17, a voltage exceeding a predetermined threshold is detected in any of the detection circuits 32A, 32B, and 32C corresponding to the three electrode pairs 80A, 80B, and 80C adjacent to each other. The determination unit 34 determines that the driver is holding the rim 12 as described above.

  As described above, when the determination unit 34 detects a voltage exceeding a predetermined threshold value in the detection circuits 32A, 32B, and 32C corresponding to the two electrode pairs adjacent to each other among the electrode pairs 80A, 80B, and 80C ( That is, when the rim 12 is grasped when the electrical resistance of the two electrode pairs adjacent to each other among the electrode pairs 80A, 80B, 80C is lower than a predetermined threshold value), the driver determines which of the pressure sensors 20A. It is prevented that the rim 12 is erroneously detected as being gripped when a part corresponding to one electrode pair is accidentally touched.

  In the present embodiment, since the upper electrode 60 and the lower electrode 50 are configured by pressure-sensitive electrodes, not the detection based on the contact or non-contact between the electrodes 50 and 60 but the push force acting on the electrodes 50 and 60. Detection based on pressure is possible. Therefore, even when the area of each electrode 50, 60 is increased, the gripping state of the rim 12 can be detected, and a wide detection range can be secured. Thus, since the area of each electrode 50 and 60 can be enlarged, the total number of electrodes 50 and 60 can be reduced. Accordingly, since the number of wirings is reduced, the circuit configuration of the pressure sensor 20A can be simplified and the cost can be reduced.

  Further, with the configuration as described above, the contact pressure can be detected independently at a plurality of locations (three locations in the illustrated example) along the circumferential direction of the cross section of the rim, and a more accurate gripping state can be detected. It becomes possible. Further, by configuring the pressure-sensitive sensor 20A as described above, the number of electrode pairs 80 that can independently detect conduction can be increased. Hereinafter, this point will be described.

  For example, as shown in FIG. 18, when two electrode pairs 80A and 80B are arranged adjacent to each other and the conduction of the two electrode pairs 80A and 80B is detected independently, one upper electrode 60A and 60B It is conceivable that the common wiring 101 is connected to each other to form one wiring system S111, and the lower electrodes 50A and 50B are respectively connected to the individual wirings 102 and 103 to form two wiring systems S112 and S113. At this time, the number of wiring systems formed on the upper substrate 26 is 1, the number of wiring systems formed on the lower substrate 22 is 2, and the maximum number of wiring systems formed on the upper substrate 26 and the lower substrate 22 is. The number is two. On the other hand, according to the present embodiment, as shown in FIG. 19, the upper electrode 60B of the electrode pair 80B among the three electrode pairs 80A, 80B, 80C and one of the electrode pairs adjacent thereto. The upper electrode 60A of 80A is connected to each other by the upper common wiring 41 to form a wiring system S2, and the lower electrode 50B of the electrode pair 80B and the lower electrode 50C of the other electrode pair 80C among the electrode pairs adjacent thereto. Are connected to each other by the lower common wiring 51 to form the wiring system S4, so that the number of wiring systems formed on the upper substrate 26 and the lower substrate 22 can be two respectively. Thus, according to the present embodiment, the number of electrode pairs 80 to be arranged is the same even though the maximum number of wiring systems formed on the upper substrate 26 and the lower substrate 22 is the same as the example shown in FIG. Can be increased by one to three.

  In the above-described embodiment, the example in which one electrode unit 75 includes three electrode pairs 80A, 80B, and 80C has been described. However, the present invention can be applied to the case where one electrode unit 75 includes four or more electrode pairs. Can be applied. FIG. 20 is a diagram schematically illustrating a wiring system when one electrode unit 75 includes four electrode pairs 80A, 80B, 80C, and 80D. In the example shown in FIG. 20, among the four electrode pairs 80A, 80B, 80C, 80D, the upper electrode 60B of the electrode pair 80B and the upper electrode 60A of one electrode pair 80A of the electrode pairs adjacent thereto are connected to the upper common wiring. 41 is connected to each other to form the wiring system S12, and the lower electrode 50B of the electrode pair 80B and the lower electrode 50C of the other electrode pair 80C among the electrode pairs adjacent thereto are connected to each other by the lower common wiring 51. Then, the wiring system S14 is formed, and the upper electrode 60C of the electrode pair 80C and the upper electrode 60D of one of the electrode pairs 80D adjacent thereto are connected to each other by the upper common wiring 141 to connect the wiring system S11. Forming. In this case, the number of wiring systems formed on the upper substrate 26 is two, and the number of wiring systems formed on the lower substrate 22 is three. When the maximum number of wiring systems formed on the upper substrate 26 or the lower substrate 22 is 3, according to the example shown in FIG. 18, only three electrode pairs can be arranged adjacent to each other, but the wiring configuration shown in FIG. Accordingly, the four electrode pairs 80A, 80B, 80C, 80D can be arranged adjacent to each other.

  FIG. 21 is a diagram schematically showing a wiring system when one electrode unit 75 includes five electrode pairs 80A, 80B, 80C, 80D, and 80E. In the example shown in FIG. 21, among the five electrode pairs 80A, 80B, 80C, 80D, 80E, the upper electrode 60B of the electrode pair 80B and the upper electrode 60A of one electrode pair 80A of the electrode pairs adjacent to the upper electrode 60A A common wiring 41 connects each other to form a wiring system S23. The lower electrode 50B of the electrode pair 80B and the lower electrode 50C of the other electrode pair 80C among the electrode pairs adjacent thereto are connected by the lower common wiring 51. Connected to each other to form a wiring system S25, and among the five electrode pairs 80A, 80B, 80C, 80D, and 80E, the upper electrode 60D of the electrode pair 80D and the upper electrode of one electrode pair 80C of the adjacent electrode pairs The electrode 60C is connected to each other by the upper common wiring 141 to form a wiring system S22. The lower electrode 50D of the electrode pair 80D and the other electrode pair 80E of the electrode pairs adjacent thereto Connected together and the negative electrode 50E in the lower common wiring 151 to form a wiring system S26. In this case, the number of wiring systems formed on the upper substrate 26 and the lower substrate 22 is 3, respectively. When the maximum number of wiring systems formed on the upper substrate 26 or the lower substrate 22 is 3, according to the example shown in FIG. 18, only three electrode pairs can be arranged adjacent to each other, but the wiring configuration shown in FIG. Accordingly, five electrode pairs 80A, 80B, 80C, 80D, and 80E can be arranged adjacent to each other.

  Thus, if the larger of the number of wiring systems formed on the upper substrate and the number of wiring systems formed on the lower substrate is N, according to the example shown in FIG. An upper electrode of the selected electrode pair, and an upper electrode of one of the two electrode pairs arranged adjacent to both sides of the selected electrode pair. Electrically connected by the upper common wiring, and the lower electrode of the selected electrode pair and the lower electrode of the other electrode pair of the two electrode pairs are electrically connected by the lower common wiring Thus, it is possible to arrange a maximum of (2N-1) electrode pairs adjacent to each other.

  In addition, since the maximum number of electrode pairs that can be arranged adjacent to each other is (2N-1), that is, an odd number, when the wiring configuration according to the present invention is employed, the number of electrode pairs is an odd number. This increases the effect of increasing the number of electrode pairs described above. If the number of electrode pairs is an odd number, the same pattern can be used as the pattern of the upper electrode 60 shown in FIG. 11 and the pattern of the lower electrode 50 shown in FIG. Can be manufactured by the same manufacturing process, and the manufacturing cost can be reduced.

  According to the first embodiment described above, since many electrode pairs that can independently detect conduction can be arranged in the electrode unit 75 with a small number of wires, the rim cross-section circumferential direction R (see FIG. 2) The position where the rim 12 is gripped can be accurately detected. However, the present invention can also be applied to the case where the position where the rim 12 is gripped in the rim extending direction E (see FIG. 1) is distinguished and detected. In other words, the present invention can also be applied to a case where the area (for example, the regions J and H) where the rim 12 is gripped is distinguished and detected. With respect to this point, referring to FIGS. 22 to 26, an example in which a grip detection device that can detect whether the area of the rim 12 gripped by the driver is the region J or the region H is configured will be described. To explain.

  22, 23, and 26, in order to facilitate understanding, among the plurality of electrode units 75, the electrode unit 75 </ b> Ja disposed in the region J adjacent to the boundary between the region J and the region H ( 24 and FIG. 25) and the electrode unit 75Ha (see FIG. 24 and FIG. 25) disposed in the region H adjacent to the boundary portion (that is, the electrode units 75Ja adjacent to each other across the boundary portion). Only the wiring configuration (at 75 Ha) is shown schematically.

  When such a grip detection device is configured by applying the above-described embodiment (see FIG. 19), it is conceivable to employ a wiring configuration as shown in FIG. According to the wiring configuration shown in FIG. 22, the wiring system S221 electrically connected to the common wiring 41Ja between the upper electrodes 60BJa and 60CJa of the electrode unit 75Ja and the detection circuits 32BJ and 32CJ of the grip detection unit 30; An individual wiring 205 for the upper electrode 60AJa of the electrode unit 75Ja and a wiring system S225 electrically connected to the detection circuit 32AJ are formed on the upper substrate 26. In addition, the wiring system S232 electrically connected to the common wiring 41Ha between the upper electrodes 60AHa and 60BHa of the electrode unit 75Ha and the detection circuits 32AH and 32BH of the grip detection unit 30, and the individual wiring 105 to the upper electrode 60CHa A wiring system S231 electrically connected to the detection circuit 32CH is formed on the upper substrate 26. That is, four wiring systems S221, S225, S231, and S232 are formed on the upper substrate 26. Here, each of the detection circuits 32AJ, 32BJ, and 32CJ is a circuit that detects conduction of the electrode pair located in the region J, and each of the detection circuits 32AH, 32BH, and 32CH is conduction of the electrode pair located in the region H. Is a circuit for detecting

  On the other hand, the lower substrate 22 has a wiring system S223 electrically connected to the common wiring 51Ja between the lower electrodes 50AJa and 50BJa of the electrode unit 75Ja and the detection circuits 32AJ and 32BJ of the grip detection unit 30; An individual wiring 204 for the lower electrode 50CJa and a wiring system S227 electrically connected to the detection circuit 32CJ are formed. Further, the wiring system S234 electrically connected to the common wiring 51Ha between the lower electrodes 50BHa and 50CHa of the electrode unit 75Ha and the detection circuits 32BH and 32CH of the grip detection unit 30, and the individual wiring for the lower electrode 50AHa A wiring system S235 electrically connected to 102 and the detection circuit 32AH is formed. That is, four wiring systems S223, S227, S234, and S235 are formed on the lower substrate 22.

  According to this wiring configuration, when the electrode pair 50AJa, 60AJa of the electrode unit 75Ja is conducted, a first circuit including the wiring systems S223, S225 and the detection circuit 32AJ is formed. When the electrode pairs 50BJa and 60BJa are turned on, a second circuit including the wiring systems S221 and S223 and the detection circuit 32BJ is formed. Further, when the electrode pairs 50CJa and 60CJa are turned on, a third circuit including the wiring systems S221 and S227 and the detection circuit 32CJ is formed. On the other hand, when the electrode pair 50AHa, 60AHa of the electrode unit 75Ha is conducted, a fourth circuit including the wiring systems S232, S235 and the detection circuit 32AH is formed. When the electrode pair 50BHa, 60BHa is conducted, a fifth circuit including the wiring systems S232, S234 and the detection circuit 32BH is formed. Furthermore, when the electrode pairs 50CHa and 60CHa are conducted, a sixth circuit including the wiring systems S231 and S234 and the detection circuit 32CH is formed.

  That is, according to such a wiring configuration, six independent circuits (first circuit to sixth circuit) are formed for each of the six electrode pairs. Of these, the first circuit to the third circuit include detection circuits 32AJ, 32BJ, and 32CJ that detect conduction of the electrode pair located in the region J, and the fourth circuit to the sixth circuit include the region H. Detection circuits 32AH, 32BH, and 32CH for detecting the conduction of the electrode pair located at. Therefore, it is possible to independently detect the conduction of the electrode pair in each of the electrode units 75Ja and 75Ha, and to distinguish whether the conducted electrode pair is arranged in the region J or the region H (that is, conduction) Can be detected by distinguishing the area where the electrode pair is arranged.

  Here, in the example of FIG. 22, the number of wiring systems formed on the upper substrate 26 is four, and similarly, the number of wiring systems formed on the lower substrate 22 is four. That is, the maximum number of wiring systems formed on the upper substrate 26 and the lower substrate 22 is four.

  Further, in the case of adding another area to be distinguished in the example of FIG. 22, in order to distinguish the added area, the electrode unit 75Ja and the electrode unit 75Ha with respect to the electrode unit 75 located in the added area. A wiring system similar to that formed in (1) is formed. That is, when the three areas are distinguished in the example of FIG. 22, two independent wiring systems are newly formed on the upper substrate 26 and the lower substrate 22 of the electrode unit 75 located in the added area. The In other words, six wiring systems are formed on each of the upper substrate 26 and the lower substrate 22. In this case, the maximum number of wiring systems formed on the upper substrate 26 and the lower substrate 22 is six. That is, according to the example of FIG. 22, the maximum number of wiring systems when distinguishing N areas is 2N.

  On the other hand, when such a gripping detection apparatus is configured without applying the above-described embodiment (see FIG. 19), for example, a wiring configuration as shown in FIG. 23 may be adopted. In the example shown in FIG. 23, the common wiring 201 electrically connected to the upper electrodes 60AJa, 60BJa, and 60CJa of the electrode unit 75Ja and the common wiring electrically connected to the upper electrodes 60AHa, 60BHa, and 60CHa of the electrode unit 75Ha. 301 and a wiring system S211 electrically connected to the common wirings 201 and 301 and the detection circuits 32AJ, 32BJ, 32CJ, 32AH, 32BH, and 32CH of the grip detection unit 30 are formed on the upper substrate 26. .

  On the other hand, on the lower substrate 22, a wiring system S212 electrically connected to the individual wiring 202 for the lower electrode 50AJa of the electrode unit 75Ja and the detection circuit 32AJ of the grip detection unit 30, and an individual wiring for the lower electrode 50BJa 203, a wiring system S213 electrically connected to the detection circuit 32BJ, a wiring 204 individually connected to the lower electrode 50CJa, a wiring system S214 electrically connected to the detection circuit 32CJ, and an electrode unit 75Ha. The wiring system S215 electrically connected to the individual wiring 102 for the lower electrode 50AHa of the two lower electrodes and the detection circuit 32AH of the grip detection unit 30, and the individual wiring 103 and the detection circuit 32BH for the lower electrode 50BHa are electrically connected. Interconnected wiring system S213, and individual wiring 104 for the lower electrode 50CHa A wiring system S217 which is electrically connected to the circuit 32CH out is formed.

  According to such a wiring configuration, when the electrode pairs 50AJa and 60AJa of the electrode unit 75Ja are conducted, a first circuit including the wiring systems S211 and S212 and the detection circuit 32AJ is formed. When the electrode pairs 50BJa and 60BJa are turned on, a second circuit including the wiring systems S211 and S213 and the detection circuit 32BJ is formed. Further, when the electrode pairs 50CJa and 60CJa are turned on, a third circuit including the wiring systems S211 and S214 and the detection circuit 32CJ is formed. On the other hand, when the electrode pairs 50AHa and 60AHa of the electrode unit 75Ha are conducted, a fourth circuit including the wiring systems S211 and S215 and the detection circuit 32AH is formed. When the electrode pairs 50BHa and 60BHa are conducted, a fifth circuit including the wiring systems S211 and S216 and the detection circuit 32BH is formed. Further, when the electrode pairs 50CHa and 60CHa are conducted, a sixth circuit including the wiring systems S211 and S217 and the detection circuit 32CH is formed.

  That is, according to such a wiring configuration, six independent circuits (first circuit to sixth circuit) are formed for each of the six electrode pairs. Of these, the first circuit to the third circuit include detection circuits 32AJ, 32BJ, and 32CJ that detect conduction of the electrode pair located in the region J, and the fourth circuit to the sixth circuit include the region H. Detection circuits 32AH, 32BH, and 32CH for detecting the conduction of the electrode pair located at. Therefore, it is possible to independently detect the conduction of the electrode pair in each of the electrode units 75Ja and 75Ha, and to distinguish whether the conducted electrode pair is arranged in the region J or the region H (that is, conduction) Can be detected by distinguishing the area where the electrode pair is arranged.

  However, in the wiring configuration shown in FIG. 23, in order to detect conduction for each electrode pair and to distinguish two areas (regions J and H of the rim 12), a wiring system is provided for each of the six lower electrodes 50. Need to form. That is, since it is necessary to form six wiring systems on the lower substrate 22, the maximum number of wiring systems formed on the upper substrate 26 and the lower substrate 22 is six.

  Further, when another area to be distinguished is added, the lower substrate 22 corresponds to the three lower electrodes 50 constituting the electrode pair in each of the electrode units 75 arranged in the added area. It is necessary to form three new independent wiring systems. In other words, it is necessary to form nine wiring systems on the lower substrate 22 in order to distinguish the three areas. That is, according to the wiring configuration shown in FIG. 23, it is necessary to form 3N wiring systems on the lower substrate 22 in order to distinguish N areas. In this case, in order to distinguish N areas. The maximum number of wiring systems is 3N.

  Thus, when the case where the wiring configuration shown in FIG. 19 is not applied is compared with the case where it is applied, the maximum number of wiring systems for distinguishing N areas is 3N when not applied. When applied, the maximum number of wiring systems is reduced to 2N. Therefore, when distinguishing and detecting the area where the rim 12 is gripped, the number of wires can be effectively reduced by applying the wiring configuration according to the present invention (see FIG. 19).

  Next, a second embodiment of the present invention will be described. According to the grip detection device 2 according to the second embodiment of the present invention, the maximum number of wiring systems can be further reduced from the above-described example of FIG. FIG. 24 is a view showing the upper substrate 26 and the wiring thereof in the pressure-sensitive sensor 20Aa of the grip detection device 2, and corresponds to FIG. FIG. 25 is a diagram showing the lower substrate 22 and its wiring in the pressure-sensitive sensor 20Aa, and corresponds to FIG.

  As shown in FIG. 24, in each of the five electrode units 75J arranged in the region J of the rim 12, the upper electrode 60BJ and the upper electrode 60CJ are electrically connected to each other by a common wiring 41 (upper common wiring). On the other hand, the upper electrode 60AJ is not electrically connected to the common wiring 41, but is electrically connected to the individual wiring. Similarly, in each of the ten electrode units 75H arranged in the region H, the upper electrode 60AH and the upper electrode 60BH are electrically connected to each other by the common wiring 41 (upper common wiring). The electrode 60CH is not electrically connected to the common wiring 41, but is electrically connected to the individual wiring.

  On the upper substrate 26, in addition to these upper electrodes 60, four wiring systems S201, S202, S205, and S206 are formed. The wiring system S201 is electrically connected to the inter-unit wiring 242 provided between the electrode units to electrically connect the electrode units to each other, and the inter-unit wiring 242 and the terminal T1 provided on the connecting portion 21A. Connecting portion wiring 243. The wiring system S202 includes an inter-unit wiring 246 and a connection part wiring 247 that is electrically connected to the inter-unit wiring 246 and a terminal T2 provided in the connection part 21A. The wiring system S205 includes an inter-unit wiring 244 and a connection portion wiring 245 that is electrically connected to the inter-unit wiring 244 and a terminal T5 provided in the connection portion 21A. The wiring system S206 includes an inter-unit wiring 248 and a connection portion wiring 249 that is electrically connected to the inter-unit wiring 248 and a terminal T6 provided in the connection portion 21A.

  The inter-unit wiring 246 of the wiring system S202 is electrically connected to the upper electrode 60BH in each of the five electrode units 75H1 located on the upper side of the electrode unit 75H, but the five electrode units 75H2 located on the lower side. And the electrode unit 75J is not electrically connected. Similarly, the inter-unit wiring 248 of the wiring system S206 is electrically connected to the upper electrode 60BH in each of the electrode units 75H2, but is electrically connected to the five electrode units 75H1 and the electrode unit 75J located on the upper side. Not connected. The inter-unit wiring 244 of the wiring system S205 is electrically connected to the upper electrode 60AJ in each of the electrode units 75J, but is not electrically connected to the electrode unit 75H.

  The inter-unit wiring 242 of the wiring system S201 is electrically connected to the upper electrode 60BJ in each of the electrode units 75J, and is electrically connected to the upper electrode 60CH in each of the electrode units 75H. The upper electrode 60BJa of the electrode unit 75Ja disposed in the region J adjacent to the boundary between the region J and the region H, and the upper electrode 60CHa of the electrode unit 75Ha disposed in the region H adjacent to the boundary. And is electrically connected. That is, the inter-unit wiring 242 includes an inter-area wiring 242A wired across the boundary between the region J and the region H, and the inter-area wiring 242A causes the electrode unit 75Ja (first electrode unit) to Two upper electrodes 60BJa and 60CJa electrically connected to each other by the common wiring 41 and one upper electrode 60CHa electrically connected to the individual wiring in the electrode unit 75Ha (second electrode unit) are electrically connected. Connected.

  As shown in FIG. 25, in each of the five electrode units 75J arranged in the region J, the lower electrode 50AJ and the lower electrode 50BJ are electrically connected to each other by a common wiring 51 (lower common wiring). On the other hand, the lower electrode 50CJ is not electrically connected to the common wiring 51, but is electrically connected to the individual wiring. Similarly, in each of the ten electrode units 75H arranged in the region H, the lower electrode 50BH and the lower electrode 50CH are electrically connected to each other by the common wiring 51 (lower common wiring). Thus, the lower electrode 50CH is not electrically connected to the common wiring 51, but is electrically connected to the individual wiring.

  On the lower substrate 22, in addition to these lower electrodes 50, five wiring systems S203, S204, and S207 to S209 are formed. The wiring system S203 includes an inter-unit wiring 252 and a connection part wiring 253 electrically connected to the inter-unit wiring 252 and a terminal T3 provided in the connection part 21A. The wiring system S204 includes an inter-unit wiring 256 and a connection portion wiring 257 electrically connected to the inter-unit wiring 256 and a terminal T4 provided in the connection portion 21A. The wiring system S207 includes an inter-unit wiring 254 and a connection portion wiring 255 electrically connected to the inter-unit wiring 254 and a terminal T7 provided in the connection portion 21A. The wiring system S208 includes an inter-unit wiring 258A and a connection portion wiring 259A electrically connected to the inter-unit wiring 258A and a terminal T8 provided in the connection portion 21A. The wiring system S209 includes an inter-unit wiring 258B and a connection portion wiring 259B electrically connected to the inter-unit wiring 258B and a terminal T9 provided in the connection portion 21A.

  The inter-unit wiring 256 of the wiring system S204 is electrically connected to the lower electrode 50BH in each of the electrode units 75H1, but is not electrically connected to the electrode unit 75H2 or the electrode unit 75J. Similarly, the inter-unit wiring 258B of the wiring system S209 is electrically connected to the lower electrode 50BH in each of the electrode units 75H2, but is not electrically connected to the electrode unit 75H1 and the electrode unit 75J. Further, the inter-unit wiring 258A of the wiring system S208 is electrically connected to the lower electrode 50AH in each of the electrode units 75H2, but is not electrically connected to the electrode unit 75H1 and the electrode unit 75J. Further, the inter-unit wiring 254 of the wiring system S207 is electrically connected to the lower electrode 50CJ in each of the electrode units 75J, but is not electrically connected to the electrode unit 75H.

  The inter-unit wiring 252 of the wiring system S203 is electrically connected to the lower electrode 50BJ in each of the electrode units 75J, and is electrically connected to the lower electrode 50AH in each of the electrode units 75H1. The lower electrode 50BJa of the electrode unit 75Ja disposed in the region J adjacent to the boundary between the region J and the region H, and the lower side of the electrode unit 75Ha disposed in the region H adjacent to the boundary. It is electrically connected to the electrode 50AHa. That is, the inter-unit wiring 252 includes an inter-area wiring 252A wired across the boundary between the region J and the region H, and the inter-area wiring 252A causes the electrode unit 75Ja (first electrode unit) to Two lower electrodes 50AJa and 50BJa electrically connected to each other by the common wiring 51 and one lower electrode 50AHa electrically connected to the individual wiring in the electrode unit 75Ha (second electrode unit) are electrically connected. Connected.

  Then, as shown in FIGS. 24 and 25, the connection wiring section 40 (9 terminals T1 to T9 provided in the connection section 21A corresponding to the nine wiring systems S201 to S209 described above extend from the grip detection section 30. By connecting to the terminal of FIG. 1), the grip detection unit 30 and each of the upper electrode 60 and the lower electrode 50 are electrically connected.

  According to such a gripping detection device 2, gripping can be detected for each electrode pair and for each area, even though the maximum number of wiring systems is further reduced compared to the example of FIG. It becomes possible. This point will be described with reference to FIG.

  As shown in FIG. 26, the upper substrate 26 in the present embodiment includes a wiring system S205 including an individual wiring 205 for the upper electrode 60AJa of the electrode unit 75Ja and an inter-unit wiring 244 electrically connected thereto, and an electrode unit. The common wiring 41Ha between the 75Ha upper electrodes 60AHa and 60BHa and the inter-unit wiring 246 electrically connected thereto, and the common wiring 41Ja and electrodes between the upper electrodes 60BJa and 60CJa of the electrode unit 75Ja A wiring system S201 including an inter-unit wiring 242 that is electrically connected to both of the individual wirings 105 for the upper electrode 60CHa of the unit 75Ha is formed. That is, three wiring systems S201, S202, and S205 are formed on the upper substrate.

  Then, by the wiring system S201, the upper electrode 60CHa of the electrode unit 75Ha, the upper electrodes 60BJa and 60CJa of the electrode unit 75Ja, the detection circuits 32BJ and 32CJ of the grip detection unit 30, and the detection circuit 32CH of the grip detection unit 30 are electrically connected. Connected. Further, the upper electrode 60AHa, 60BHa of the electrode unit 75Ha and the detection circuits 32AH, 32BH of the grip detection unit 30 are electrically connected by the wiring system S202, and the upper electrode 60AJa of the electrode unit 75Ja and the detection circuit are electrically connected by the wiring system S205. 32AJ is electrically connected.

  On the other hand, on the lower substrate 22, a wiring system S207 including the individual wiring 204 for the lower electrode 50CJa of the electrode unit 75Ja and the inter-unit wiring 254 electrically connected thereto, and the lower electrode 50BHa, 50CHa common wiring 51Ha and the wiring system S204 including the inter-unit wiring 256 electrically connected thereto, the lower electrode 50AJa of the electrode unit 75Ja, the lower side of the electrode unit 75Ha common wiring 51Ja and 50BJa A wiring system S203 including an inter-unit wiring 252 that is electrically connected to both of the individual wirings 102 for the electrode 50AHa is formed. That is, three wiring systems S203, S204, and S207 are formed on the lower substrate 22.

  And by wiring system S203, lower electrodes 50AJa and 50BJa of electrode unit 75Ja, lower electrodes 50AHa of electrode unit 75Ha, detection circuits 32AJ and 32BJ of grip detection unit 30, and detection circuit 32AH of grip detection unit 30 Are electrically connected. Further, the lower electrode 50BHa, 50CHa of the electrode unit 75Ha and the detection circuits 32BH, 32CH of the grip detection unit 30 are electrically connected by the wiring system S204, and the lower electrode 50CJa of the electrode unit 75Ja is connected by the wiring system S207. The detection circuit 32CJ is electrically connected.

  According to such a wiring configuration, when the electrode pair 50AJa, 60AJa of the electrode unit 75Ja is conducted, a first circuit including the wiring systems S203, S205 and the detection circuit 32AJ is formed. When the electrode pairs 50BJa and 60BJa are turned on, a second circuit including the wiring systems S201 and S203 and the detection circuit 32BJ is formed. Furthermore, when the electrode pairs 50CJa and 60CJa are conducted, a third circuit including the wiring systems S201 and S207 and the detection circuit 32CJ is formed. On the other hand, when the electrode pair 50AHa, 60AHa of the electrode unit 75Ha is conducted, a fourth circuit including the wiring systems S202, S203 and the detection circuit 32AH is formed. Further, when the electrode pair 50BHa, 60BHa is conducted, a fifth circuit including the wiring systems S202, S204 and the detection circuit 32BH is formed. Furthermore, when the electrode pairs 50CHa and 60CHa are conducted, a sixth circuit including the wiring systems S201 and S204 and the detection circuit 32CH is formed.

  That is, according to such a wiring configuration, six independent circuits (first circuit to sixth circuit) are formed for each of the six electrode pairs. Of these, the first circuit to the third circuit include detection circuits 32AJ, 32BJ, and 32CJ that detect conduction of the electrode pair located in the region J, and the fourth circuit to the sixth circuit include the region H. Detection circuits 32AH, 32BH, and 32CH for detecting the conduction of the electrode pair located at. Therefore, it is possible to independently detect the conduction of the electrode pair in each of the electrode units 75Ja and 75Ha, and to distinguish whether the conducted electrode pair is arranged in the region J or the region H (that is, conduction) Can be detected by distinguishing the area where the electrode pair is arranged.

  Further, according to the present embodiment, as described above, the maximum number of wiring systems formed on the upper substrate 26 is 3, and similarly, the number of wiring systems formed on the lower substrate 22 is also 3. That is, since the maximum number of wiring systems formed on the upper substrate 26 and the lower substrate 22 is 3, the maximum number of wiring systems can be further reduced compared to the example of FIG. 22 (maximum number of wiring systems 4). .

  Furthermore, according to the present embodiment, the wiring systems S201 and S203 that are electrically connected to the two electrode units adjacent to each other across the boundary portion of the area are provided. Therefore, another area to be distinguished is added. In the case of three areas, it is only necessary to newly form one wiring system in addition to the wiring system S201 on the upper substrate 26 of the electrode unit arranged in the added area. Similarly, it is sufficient to newly form one wiring system on the lower substrate 22 in addition to the wiring system S203.

  That is, when the three areas are distinguished, four wiring systems are formed on each of the upper electrode 26 and the lower electrode 22, so that the maximum number of wiring systems formed on the upper substrate 26 and the lower substrate 22. However, the maximum number of wiring systems increases only by 1 compared to the case where two areas are distinguished (maximum number of wiring systems is 3). In other words, by adopting the second embodiment of the present invention, the maximum number of wiring systems formed on the upper substrate 26 and the lower substrate 22 is suppressed to (N + 1) when N areas are distinguished. be able to. Therefore, the maximum number of wiring systems can be further reduced as compared with the example of FIG. 22 described above (maximum number of wiring systems 2N).

  As described above, according to the second embodiment of the present invention, the wiring system formed on the upper substrate 26 and the lower substrate 22 when the conduction of the electrode pair is detected for each electrode pair and by distinguishing the areas. Therefore, it is possible to perform the accurate grip detection while distinguishing the gripped area with a simpler circuit configuration.

  In FIG. 26, the region H1 and the region H2 are not distinguished for ease of explanation. However, as shown in FIGS. 24 and 25, the wiring systems S202, S203, and S204 are arranged in the region H of the rim 12. Are located only in the region H1. Therefore, the area of the rim 12 that is actually detected when any of the three electrode pairs of the electrode unit 75Ha is conducted is the region H1 (upper left side of the rim 12). As shown in FIGS. 24 and 25, the pressure-sensitive sensor 20a according to this embodiment further includes wiring systems S206, S208, and S209 that are located only in the region H2 of the rim 12. Therefore, when the driver grips the area of the rim 12 where these wiring systems S206, S208, and S209 are located, it is determined (detected) that the region H2 (lower left side of the rim 12) is gripped.

  In the second embodiment described above, the upper electrodes 60BJ and 60CJ are electrically connected by the common wiring 41 in each of the electrode units 75J located in the region J, and each of the electrode units 75H located in the region H is provided. The upper electrodes 60AH and 60BH are electrically connected by the common wiring 41 (see FIG. 24). Instead, the upper electrodes 60AJ and 60BJ are electrically connected by the common wiring 41 and the upper electrodes 60AH and 60BH may be electrically connected by the common wiring 41. Alternatively, the upper electrodes 60BJ and 60CJ may be electrically connected by the common wiring 41 and the upper electrodes 60BH and 60CH may be electrically connected by the common wiring 41. Alternatively, the upper electrodes 60AJ and 60BJ may be electrically connected by the common wiring 41, and the upper electrodes 60BH and 60CH may be electrically connected by the common wiring 41. The same applies to the lower substrate 22.

  In the above-described second embodiment, the example in which the wiring configuration shown in FIG. 26 is adopted for the electrode unit 75 including three electrode pairs has been described. However, the electrode unit 75 including four or more electrode pairs is also used. It goes without saying that the wiring configuration shown in FIG. 26 can be adopted.

  In the above-described embodiment, the voltage between the upper electrode 60 and the lower electrode 50 is measured in order to detect the electrical resistance formed between the upper electrode 60 and the lower electrode 50 of the electrode pair 80. However, if there is a certain relationship with the electric resistance formed between the upper electrode 60 and the lower electrode 50, the upper electrode 60 and the lower electrode 50 are measured by measuring a physical quantity (for example, current) other than voltage. The electrical resistance formed between the two may be detected.

  In the above-described embodiment, an example in which both the upper electrode 60 and the lower electrode 50 are pressure-sensitive electrodes has been described. However, only one of the upper electrode 60 and the lower electrode 50 may be a pressure-sensitive electrode.

  In addition, the terms “lower” and “upper” used in this specification and other terms indicating positional relationships are used in the context of the illustrated embodiment, and vary depending on the relative positional relationship of the apparatus. To do.

  Although one embodiment of the present invention has been described so far, it is needless to say that the present invention is not limited to the above-described embodiment, and 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 Cushioning material 18 Skin 20A, 20B, 20C Pressure sensor 21A, 21B, 21C Connection part 22 Lower side board 22A Substrate piece 24 Substrate spacer 24A Substrate spacer piece 25 Through hole 26 Upper substrate 26A Substrate 30 Grip detection unit 32AJ, 32BJ Detection circuit 34 Judgment unit 40 Connection wiring unit 41 Upper common wiring 42 to 47 Wiring 50 Lower electrode 51 Lower common wiring 52 to 57 Wiring 60 Upper electrode 75 Electrode Unit 80, 80A, 80B, 80C, 80D, 80E Electrode pair 90 Electrode spacers 102 to 105 Individual wiring 141 Upper common wiring 151 Lower common wiring 242, 244, 246, 248 Inter-area wiring 243, 245, 247, 249 Wiring 252 , 254, 256, 258A, 258B Inter-area wiring 253, 255, 257, 259A, 259B Connection part wiring

Claims (9)

A pressure sensor built into the rim of the steering wheel,
A lower substrate attachable to the rim;
An upper substrate disposed above the lower substrate;
At least three electrode pairs each including a lower electrode attached to the upper surface of the lower substrate and an upper electrode attached to the lower surface of the upper substrate so as to face the lower electrode, And at least one of the lower electrodes is composed of at least three electrode pairs constituted by pressure-sensitive electrodes;
A substrate spacer disposed around the at least three electrode pairs, the substrate spacer disposed between the upper substrate and the lower substrate;
The upper electrode of the electrode pair selected from the at least three electrode pairs is electrically connected to the upper electrode of one of the two electrode pairs arranged adjacent to both sides of the selected electrode pair. Upper common wiring to be connected
The lower electrode in the selected electrode pair and a lower common wiring that electrically connects the lower electrode of the other electrode pair of the two electrode pairs. Pressure sensor.   At least one electrode spacer disposed inside the substrate spacer so that the lower electrode and the upper electrode facing each other are separated from each other, and the length in a first direction corresponding to the extending direction of the rim 2. The apparatus according to claim 1, further comprising at least one electrode spacer formed so as to be shorter than a length in a second direction corresponding to a circumferential direction of a rim cross section perpendicular to a direction in which the rim extends. Pressure sensor. A pressure sensor built into the rim of the steering wheel,
A plurality of electrode units including a first electrode unit and a second electrode unit adjacent to each other, the electrode units being connected in a first direction corresponding to the extending direction of the rim;
Each of the plurality of electrode units is
A lower substrate attachable to the rim;
An upper substrate disposed above the lower substrate;
At least three electrode pairs each including a lower electrode attached to the upper surface of the lower substrate and an upper electrode attached to the lower surface of the upper substrate so as to face the lower electrode, And at least one of the lower electrodes is composed of at least three electrode pairs constituted by pressure-sensitive electrodes;
A substrate spacer disposed around the at least three electrode pairs, the substrate spacer disposed between the upper substrate and the lower substrate;
The upper electrode of the electrode pair selected from the at least three electrode pairs is electrically connected to the upper electrode of one of the two electrode pairs arranged adjacent to both sides of the selected electrode pair. Upper common wiring to be connected
A lower common wiring that electrically connects the lower electrode in the selected electrode pair and the lower electrode of the other electrode pair of the two electrode pairs;
The two upper electrodes electrically connected to the upper common wiring in the first electrode unit and the one upper electrode not electrically connected to the upper common wiring in the second electrode unit are electrically connected. Connected,
Two lower electrodes that are electrically connected to the lower common wiring in the first electrode unit, and one lower side that is not electrically connected to the lower common wiring in the second electrode unit A pressure sensitive sensor characterized in that the electrode is electrically connected. At least one of the plurality of electrode units is at least one electrode spacer disposed inside the substrate spacer such that the lower electrode and the upper electrode facing each other are spaced apart from each other, It further comprises at least one electrode spacer formed so that the length in the direction is shorter than the length in the second direction corresponding to the circumferential direction of the rim cross section perpendicular to the extending direction of the rim. The pressure-sensitive sensor according to claim 3.   5. The at least three electrode pairs are arranged along a first direction corresponding to a circumferential direction of a rim cross section perpendicular to a direction in which the rim extends. The pressure-sensitive sensor described.   6. The pressure-sensitive sensor according to claim 1, wherein the number of the at least three electrode pairs is an odd number. The pressure-sensitive sensor according to any one of claims 1 to 6, incorporated in a rim of a steering wheel;
The driver is electrically connected to the upper electrode and the lower electrode of the pressure sensor, and is based on a conduction state between the upper electrode of the pressure sensor and the lower electrode facing the upper electrode. A grip detection unit that detects that the rim is gripped,
A gripping detection device comprising: The grip detection unit
A detection circuit electrically connected to the upper electrode and the lower electrode in the at least three electrode pairs of the pressure sensor, the upper electrodes of each of the at least three electrode pairs of the pressure sensor. And a detection circuit for detecting an electrical resistance formed between the lower electrode and the lower electrode;
A determination unit that determines a gripping state of the rim of the steering wheel based on an output from the detection circuit;
The grip detection apparatus according to claim 7, comprising:   When the determination unit of the grip detection unit determines that the electrical resistance of each of two electrode pairs adjacent to each other among the at least three electrode pairs is lower than a predetermined threshold, the rim of the steering wheel The grip detection device according to claim 8, wherein the grip detection device is configured to determine that the grip is gripped.

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