Contact detection device

Abstract

To easily connect detection electrodes to a detection unit.SOLUTION: In a steering wheel 10, when a passenger grips a rim part and a capacitance between the passenger and a conductive fabric 20 of the rim part is equal to or greater than a predetermined capacitance, a control unit 36 detects the grip by the passenger on the rim part. Here, a terminal 26 is conductive to the conductive fabric 20 from the back side, and the conductive fabric 20 is connected to the control unit 36 via the terminal 26. Therefore, the conductive fabric 20 can be easily connected to the control unit 36.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a contact detection device that detects a passenger's contact with a steering wheel. [Background technology]

[0002] In the steering wheel described in Patent Document 1 below, a detection board detects contact of the rim with an occupant based on the electrostatic capacitance between the occupant touching the rim and a conductive layer of the rim.

[0003] Here, in this steering wheel, the terminal portion of the conductive layer is connected to the detection board. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2016-165940 A Summary of the Invention [Problem to be solved by the invention]

[0005] In consideration of the above, an object of the present invention is to provide a contact detection device in which a detection electrode can be easily connected to a detection unit. [Means for solving the problem]

[0006] A contact detection device of a first aspect of the present invention includes a steering wheel that is touched and operated by an occupant to steer a vehicle, a detection electrode provided on the steering wheel, a terminal portion that is conductive to the detection electrode from the back side, and a detection portion to which the detection electrode is connected via the terminal portion, the detection portion detecting contact of the occupant with the steering wheel based on electrostatic capacitance between the occupant touching the steering wheel and the detection electrode.

[0007] A contact detection device according to a second aspect of the present invention is the contact detection device according to the first aspect of the present invention, wherein the terminal portion sandwiches the detection electrode.

[0008] A third aspect of the contact detection device of the present invention is a contact detection device of the first or second aspect of the present invention, comprising an outer periphery layer that constitutes the outer periphery of the steering wheel, an adhesive layer that bonds the detection electrode and the outer periphery layer, and a limiting layer that is provided at the terminal portion arrangement position of the detection electrode and limits the adhesion between the detection electrode and the outer periphery layer by the adhesive layer.

[0009] A contact detection device according to a fourth aspect of the present invention is the contact detection device according to any one of the first to third aspects of the present invention, further comprising an outer periphery layer that constitutes an outer periphery of the steering wheel and in which the terminal portion is not provided.

[0010] A contact detection device of a fifth aspect of the present invention is a contact detection device of any one of the first to fourth aspects of the present invention, comprising an outer periphery layer that forms the outer periphery of the steering wheel and is formed by connecting a plurality of components at connecting parts, and a recess that is provided on the steering wheel and into which the connecting parts and the detection electrodes are inserted with the detection electrodes arranged along the connecting parts. Effect of the Invention

[0011] In the contact detection device according to the first aspect of the present invention, a vehicle is steered by an occupant touching a steering wheel and operating the steering wheel. A detection electrode of the steering wheel is connected to a detection unit, and the detection unit detects the contact of the occupant with the steering wheel based on the electrostatic capacitance between the detection electrode and the occupant touching the steering wheel.

[0012] Here, the terminal portion is electrically connected to the detection electrode from the rear side, and the detection electrode is connected to the detection portion via the terminal portion, so that the detection electrode can be easily connected to the detection portion.

[0013] In the contact detection device according to the second aspect of the present invention, the terminal portion sandwiches the detection electrode, thereby making it possible to appropriately electrically connect the terminal portion to the detection electrode.

[0014] In the contact detection device according to the third aspect of the present invention, the outer periphery of the steering wheel is configured by an outer periphery layer, and the detection electrode and the outer periphery layer are bonded by an adhesive layer.

[0015] The limiting layer at the position where the terminal of the detection electrode is disposed limits the adhesion between the detection electrode and the outer peripheral layer by the adhesive layer, and therefore the rigidity at the position where the terminal of the detection electrode is disposed can be increased by the limiting layer.

[0016] In the contact detection device according to the fourth aspect of the present invention, the outer periphery of the steering wheel is configured by the outer periphery layer, and no terminal portion is provided on the outer periphery layer, so that the terminal portion can be prevented from interfering with the assembly of the outer periphery layer.

[0017] In the contact detection device according to the fifth aspect of the present invention, the outer periphery of the steering wheel is constituted by an outer periphery layer, and the outer periphery layer is constituted by connecting a plurality of components at a connecting portion. Furthermore, the connecting portion and the detection electrode are inserted into a recess of the steering wheel with the detection electrode disposed along the connecting portion. This makes it possible to prevent an air layer from being formed between the connecting portion and the detection electrode, and to increase the accuracy of the capacitance between the detection electrode and an occupant who comes into contact with the connecting portion of the outer periphery layer. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a front view showing a steering wheel according to a first embodiment of the present invention, as viewed from the front side. [Diagram 2] 2A is an exploded view showing the cover body of the steering wheel according to the first embodiment of the present invention from the back side, and FIG. 2B is a cross-sectional view of the steering wheel according to the first embodiment of the present invention (cross-sectional view taken along line 2B-2B in FIG. 1). [Diagram 3] 1 is a cross-sectional view showing a cover body of a steering wheel according to a first embodiment of the present invention. [Figure 4] 1 is a perspective view showing an assembled state of a steering wheel according to a first embodiment of the present invention, viewed from diagonally above on the right. [Diagram 5] FIG. 6 is a cross-sectional view showing a cover body of a steering wheel according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] [First embodiment] 1 shows a front view of a steering wheel 10 according to a first embodiment to which a contact detection device of the present invention is applied. In the drawing, the front of the steering wheel 10 is indicated by an arrow FR, the upper side of the steering wheel 10 is indicated by an arrow UP, the right side of the steering wheel 10 is indicated by an arrow RH, and the circumferential direction of the steering wheel 10 is indicated by an arrow C.

[0020] The steering wheel 10 according to this embodiment faces the front of the driver's seat of the vehicle, and is disposed in front of a passenger (driver) seated in the driver's seat. The front, upper, and right sides of the steering wheel 10 are directed obliquely upward and rearward, obliquely upward and forward, and rightward, respectively, of the vehicle.

[0021] 1, the central portion of the steering wheel 10 is a boss portion 10A, and the peripheral portion of the steering wheel 10 is a rim portion 10B that is annular in front view and has a circular cross section and serves as a gripping portion. Three spoke portions 10C are provided between the boss portion 10A and the rim portion 10B as connecting portions, and the spoke portions 10C extend leftward, rightward, and downward from the boss portion 10A and are connected to the rim portion 10B.

[0022] The boss portion 10A is fixed to the rear end (upper end) of the vehicle of a cylindrical steering shaft 12 serving as a support member for the vehicle, and the steering shaft 12 is disposed coaxially with the rim portion 10B. The steering wheel 10 is supported by the steering shaft 12 so as to be integrally rotatable, and when a driver grips the rim portion 10B and rotates the steering wheel 10 in the circumferential direction, the steering shaft 12 rotates about the central axis to steer the vehicle.

[0023] The inner outer periphery of the rim portion 10B is made of a rim base material 14 (see Figure 4), which is made of polyurethane. Grooves 14A (see Figure 2(B)) with a rectangular cross section are formed as recesses on the outer periphery of the rim base material 14 in the upper left, lower left, upper right, and lower right portions, and the grooves 14A are open to the outside of the outer periphery of the rim base material 14 and are arranged all around the circumferential direction of the rim portion 10B (the direction around the circumferential direction of the steering wheel 10).

[0024] An annular, band-shaped cover body 16 (see FIGS. 2(A), 3 and 4) is attached to the outer periphery of the rim base material 14, and the cover body 16 covers the outer periphery of the rim base material 14.

[0025] The cover body 16 is provided with an annular and band-shaped leather 18 as an outer peripheral layer, and the leather 18 forms the outer periphery of the rim portion 10B and is an insulator. The leather 18 is made up of a plurality of (four in this embodiment) substantially rectangular pieces 18A as constituent materials, and the plurality of pieces 18A are connected in an annular shape. The ends of the pieces 18A are folded back on the leather 18 and connected by sewing in a state where they are overlapped (see FIG. 2(B)). A connecting portion 18B between the pieces 18A and 18A is formed by the ends of a pair of pieces 18A. The leather 18 is assembled to the rim base material 14 by connecting both ends in the width direction (both ends on the inner periphery side of the steering wheel 10) by sewing in a state where the leather 18 is wrapped around the rim base material 14 in the circumferential direction of the steering wheel 10 and the circumferential direction of the rim portion 10B, and the leather 18 is assembled to the rim base material 14, and the connecting portion 18B of the leather 18 is inserted into the groove 14A of the rim base material 14.

[0026] A plurality of (two in this embodiment) long rectangular sheet-like conductive cloths 20 are provided on the back side of the leather 18 as detection electrodes, and the conductive cloths 20 are made of conductive cloth (woven fabric). The conductive cloths 20 extend in the circumferential direction of the leather 18, and are disposed on the rim portions 10B on the left and right sides of the steering wheel 10.

[0027] A double-sided tape 22 is adhered to the front side of the conductive cloth 20 as an adhesive layer, and the double-sided tape 22 is made of an insulator. The front side of the double-sided tape 22 is adhered to the back side of the leather 18, and the double-sided tape 22 adheres the conductive cloth 20 to the leather 18. The conductive cloth 20 is adhered to the leather 18 by the double-sided tape 22 before the leather 18 is assembled to the rim base material 14, and at the position of the connecting portion 18B of the leather 18, the conductive cloth 20 is arranged along the connecting portion 18B (see FIG. 2(B)). The conductive cloth 20 is assembled by being wrapped around the rim base material 14 together with the leather 18, and the conductive cloth 20 is inserted into the groove 14A of the rim base material 14 together with the connecting portion 18B.

[0028] A protrusion 20A is provided at one longitudinal end of the conductive cloth 20 (the end below the steering wheel 10), and the protrusion 20A protrudes to one widthwise side of the conductive cloth 20 (the rear side of the steering wheel 10), and protrudes to one widthwise side of the leather 18. On the front side of the protrusion 20A, release paper 22A remains as a limiting layer on the front side of the double-sided tape 22, and the release paper 22A limits the adhesion of the double-sided tape 22 of the protrusion 20A to the leather 18 and serves as an insulator. A circular insertion hole 24 is formed through the protrusion 20A, and the insertion hole 24 also penetrates the double-sided tape 22 and the release paper 22A.

[0029] The protruding portion 20A is provided with a terminal portion 26. The terminal portion 26 is provided with a metal rivet 28 as an engagement member, the leg of the rivet 28 being inserted into the insertion hole 24, and the head of the rivet 28 being disposed on the front side of the release paper 22A. A metal round terminal 30 as a terminal is provided on the back side of the protruding portion 20A, and the leg of the rivet 28 is inserted into the annular plate-shaped tip of the round terminal 30. A metal push nut 32 having a substantially annular plate shape as an engagement member is provided on the side of the round terminal 30 opposite the protruding portion 20A, and the leg of the rivet 28 penetrates into the push nut 32. The push nut 32 is elastically engaged with the leg of the rivet 28, thereby locking the movement of the push nut 32 toward the side opposite the round terminal 30. Between the push nut 32 and the head of the rivet 28, the round terminal 30, the protrusion 20A, the double-sided tape 22 and the release paper 22A are sandwiched, and the round terminal 30 is in contact with the protrusion 20A from the back side and is electrically connected.

[0030] A harness 34 is connected to the base end of the round terminal 30, and the harness 34 is connected to a control device 36 (ECU) serving as a detection unit. Therefore, the conductive cloth 20 is connected to the control device 36 via the terminal portion 26 (round terminal 30) and the harness 34. In addition, the protruding portion 20A of the conductive cloth 20 (including the double-sided tape 22, the release paper 22A, the terminal portion 26, and the harness 34) is covered and protected by a protective tape 38.

[0031] Next, the operation of this embodiment will be described.

[0032] In the steering wheel 10 configured as described above, when an occupant grips the rim portion 10B and the electrostatic capacitance between the occupant's hand and the conductive cloth 20 of the cover body 16 on the rim portion 10B is equal to or greater than a predetermined capacitance, the control device 36 detects the occupant's gripping (contact) of the rim portion 10B.

[0033] Here, the round terminal 30 of the terminal portion 26 is electrically connected to the protruding portion 20A of the conductive cloth 20 from the back side, and the conductive cloth 20 is connected to the control device 36 via the terminal portion 26 and the harness 34. Therefore, the conductive cloth 20 can be easily connected to the control device 36.

[0034] Furthermore, in the terminal portion 26, the conductive cloth 20 is sandwiched between the round terminal 30 and the head of the rivet 28. Therefore, the round terminal 30 can be appropriately electrically connected to the conductive cloth 20.

[0035] In addition, release paper 22A remains on protruding portion 20A (position where terminal portion 26 is arranged) of conductive cloth 20. Therefore, the rigidity of protruding portion 20A of conductive cloth 20 can be increased by release paper 22A, and terminal portion 26 (rivet 28, round terminal 30, and push nut 32) can be easily assembled to protruding portion 20A.

[0036] Furthermore, in the cover body 16, no other conductive cloth or insulator between the conductive cloths is provided on the back side of the conductive cloth 20. This allows the cover body 16 to be made thin, the rigidity of the cover body 16 to be reduced, and the cover body 16 can be easily wrapped around and assembled to the rim base material 14 of the rim portion 10B.

[0037] Furthermore, in the cover body 16, the leather 18 is not provided with the terminal portion 26. Therefore, it is possible to prevent the terminal portion 26 from interfering with the assembly (wrapping) of the leather 18 onto the rim base material 14.

[0038] Furthermore, the connecting portion 18B and the conductive cloth 20 are inserted into the groove 14A of the rim base material 14 with the conductive cloth 20 arranged along the connecting portion 18B between the pieces 18A of the leather 18. This makes it possible to prevent an air layer from being formed between the connecting portion 18B and the conductive cloth 20, and to increase the accuracy of the capacitance between the occupant gripping the connecting portion 18B position of the leather 18 and the conductive cloth 20, thereby increasing the accuracy of detection of the occupant's grip on the rim portion 10B. Moreover, the connecting portion 18B and the conductive cloth 20 can be appropriately inserted into the groove 14A, and it is possible to prevent the leather 18 from being protruded by the connecting portion 18B and the conductive cloth 20, thereby reducing the appearance of the leather 18.

[0039] [Second embodiment] FIG. 5 shows a cross-sectional view of a cover body 16 of a steering wheel 50 according to a second embodiment to which a contact detection device of the present invention is applied.

[0040] The steering 50 according to this embodiment has a configuration substantially similar to that of the first embodiment, but differs in the following respects.

[0041] As shown in FIG. 5, in the steering wheel 50 according to this embodiment, a long rectangular sheet-shaped heater 52 is provided as a heating mechanism on the back side of the conductive cloth 20 excluding the protruding portion 20A. The heater 52 extends in the circumferential direction of the leather 18 and has a heating wire (not shown) provided by printing.

[0042] A double-sided tape 54 is attached to the front side of the heater 52 as an additional adhesive layer, and the double-sided tape 54 is made of an insulator. The front side of the double-sided tape 54 is attached to the back side of the conductive cloth 20, and the double-sided tape 54 attaches the heater 52 to the leather 18 and the conductive cloth 20. The heater 52 is attached to the conductive cloth 20 by the double-sided tape 54 before the leather 18 and the conductive cloth 20 are assembled to the rim base material 14, and at the position of the connecting portion 18B of the leather 18, the conductive cloth 20 and the heater 52 are arranged along the connecting portion 18B. The heater 52 is assembled by being wrapped around the rim base material 14 of the rim portion 10B together with the leather 18 and the conductive cloth 20, and the heater 52 is inserted into the groove 14A of the rim base material 14 together with the connecting portion 18B and the conductive cloth 20.

[0043] A harness 56 is connected to the heater 52 (heating wire), and the harness 56 is connected to the control device 36. Therefore, the heater 52 is connected to the control device 36 via the harness 56.

[0044] Here, in this embodiment as well, it is possible to achieve the same functions and effects as in the first embodiment.

[0045] Furthermore, current is supplied to the heater 52 (electric heating wire) under the control of the control device 36, and the heater 52 (electric heating wire) generates heat. This allows the heater 52 to heat the rim portion 10B.

[0046] In addition, the conductive cloth 20 and the heater 52 are arranged along the connecting portion 18B of the leather 18. Therefore, the connecting portion 18B, the conductive cloth 20, and the heater 52 can be appropriately inserted into the groove 14A of the rim base material 14, and it is possible to prevent the leather 18 from being protruded by the connecting portion 18B, the conductive cloth 20, and the heater 52, thereby preventing the appearance of the leather 18 from being deteriorated.

[0047] In the first and second embodiments, the release paper 22A of the double-sided tape 22 remains on the protruding portion 20A of the conductive cloth 20. However, the release paper 22A of the double-sided tape 22 does not have to remain on the protruding portion 20A of the conductive cloth 20. [Explanation of symbols]

[0048] 10···Steering wheel, 14A···Groove (recess), 18···Leather (outer peripheral layer), 18A···Piece (component), 18B···Connecting part, 20···Conductive cloth (detection electrode), 22···Double-sided tape (adhesive layer), 22A···Release paper (limiting layer), 26···Terminal part, 36···Control device (detection part), 50···Steering wheel

Claims

1. A steering wheel that is operated by a passenger in contact with the steering wheel to steer the vehicle; A detection electrode provided on the steering wheel; a terminal portion electrically connected to the detection electrode from a rear side; a detection unit that detects a touch of an occupant with the steering wheel based on an electrostatic capacitance between the detection electrode and the occupant touching the steering wheel, the detection electrode being connected to the detection electrode via the terminal unit; A contact detection device comprising:

2. The contact detection device according to claim 1 , wherein the terminal portion sandwiches the detection electrode.

3. An outer periphery layer that configures the outer periphery of the steering wheel; an adhesive layer that bonds the detection electrode and the outer peripheral layer; a limiting layer provided at a position where the terminal portion of the detection electrode is arranged, the limiting layer limiting adhesion between the detection electrode and the outer peripheral layer by the adhesive layer; The contact detection device according to claim 1 .

4. The contact detection device according to claim 1 , further comprising an outer periphery layer that constitutes an outer periphery of the steering wheel and on which the terminal portion is not provided.

5. An outer periphery layer that configures the outer periphery of the steering wheel and is configured by connecting a plurality of components at connecting portions; a recess provided in the steering wheel, into which the coupling portion and the detection electrode are inserted with the detection electrode disposed along the coupling portion; The contact detection device according to claim 1 .

Images