handle

Abstract

To provide a steering wheel in which a coating film-like sensor layer for detecting gripping and a terminal can be stably connected.SOLUTION: In a steering wheel W1, a sensor layer 13 formed of a coating film containing a conductive material is disposed on the front side of a soft coating layer 10 disposed around a metal core 6, so that gripping during steering can be detected. The sensor layer allows the connection of a terminal 30 of a lead wire electrically continuous with a gripping detection circuit. The sensor layer includes a planar conduction surface 14a on a conduction portion 14 electrically continuous with the terminal. The terminal is formed in a plate shape having a connection surface 31 along the conduction surface. An elastically deformable conductive body 35 is disposed between the conduction surface and the connection surface. The steering wheel includes screw means 37 for fastening a support member 20 supporting the back side of the connection surface on the terminal and a metal core side portion on which the conduction portion of the sensor layer is disposed, in such a manner that they come close to each other.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a steering wheel having a sensor layer that can detect a driver's grip at a location where the driver grips the steering wheel when steering the steering wheel. [Background technology]

[0002] Conventionally, in this type of steering wheel, a sensor layer made of a sheet-like conductive material capable of detecting gripping by an increase in electrostatic capacitance is arranged in the gripping portion that is gripped when steering (see, for example, Patent Document 1). The sensor layer is arranged on the surface side of the gripping portion of the steering wheel, and terminals of lead wires extending from a grip detection circuit that detects gripping are riveted in place. The sensor layer is arranged by, for example, adhering to the surface side of the coating layer around the core metal of the gripping portion of the steering wheel. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-63761 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, when the sensor layer for detecting the grip is arranged on the surface of the coating layer around the core metal like a thin coating, even if a terminal is arranged on the surface side of the sensor layer, there is no space on the back side of the sensor layer to expand the diameter of the tip side of the rivet that has been penetrated and riveted the terminal to the sensor layer, so that the coating-like sensor layer and the terminal cannot be smoothly connected. In this case, it is possible to fasten the terminal by penetrating a fastening means such as a rivet or a screw so as to penetrate the coating layer and the core metal with the terminal placed on the front side of the sensor layer. However, even in this case, if the sensor layer is arranged on the front side of the coating layer and the head of the rivet or screw presses the sensor layer against the coating layer during fastening, there is a risk that the part of the sensor layer that contacts the terminal will cause a crack such as a break due to the elastic deformation of the coating layer on the back side of the sensor layer, and the terminal cannot be stably connected to the sensor layer, making it difficult to ensure a stable conductive state between the sensor layer and the terminal. In particular, the coating layer that covers the core wire is usually made of a soft material such as urethane foam, and since the elastic deformation of the coating layer is large, the portion of the sensor layer that comes into contact with the terminal can be broken or otherwise damaged due to the elastic deformation of the coating layer, making it impossible to stably connect the terminal to the sensor layer.

[0005] The present invention is devised to solve the above-mentioned problems, and has an object to provide a handle that can stably connect a coating-like sensor layer for grip detection to a terminal. [Means for solving the problem]

[0006] In the steering wheel according to the present invention, a sensor layer made of a coating film containing a conductive material is disposed on the surface side of a soft coating layer disposed around a core metal so that the steering wheel can be detected when the steering wheel is being steered. The sensor layer is a handle for connecting a terminal of a lead wire that is connected to a grip detection circuit for detecting a grip, the sensor layer disposed on the surface side of the coating layer covering the core metal has a flat conductive surface at a conductive portion with the terminal, The terminal is formed in a plate shape having a connection surface along the conductive surface, an elastically deformable conductor is disposed between the conductive surface and the connection surface; a screw means for fastening a support member for supporting a rear side of the connection surface of the terminal and a portion of the sensor layer on the side of the core metal, the portion having the conductive portion disposed thereon, so as to bring them closer to each other; The present invention is characterized in that it is configured to include the following.

[0007] In the handle according to the present invention, when the conductive portion of the sensor layer, the conductor, the connection surface of the terminal, and the support are overlapped and the screw means is fastened so as to bring the core metal side and the support side closer together, the conductive surface of the conductive portion of the sensor layer and the connection surface of the terminal are electrically connected through the conductor compressed to generate a wide contact surface. That is, in this fastened state, the conductor is interposed between the sensor layer and the terminal while playing the role of a buffer material and contacting the sensor layer and the terminal in intimate contact with each other over a wide contact area, so that the terminal is crimped through the conductor with a wide contact surface to the extent that the sensor layer follows the deformation of the soft coating layer and does not break, and therefore a good and stable electrical connection with the terminal can be ensured.

[0008] Therefore, in the handle according to the present invention, the coating-like sensor layer for grip detection and the terminals can be stably connected, enabling good grip detection.

[0009] In the handle according to the present invention, it is preferable that the screw means is disposed on both sides of the conductor.

[0010] In such a configuration, since screw means are provided on both sides of the conductor, when the conductor is compressed, the conductive surface of the sensor layer and the connection surface of the terminal can be brought closer together while maintaining a parallel state, so that the terminal can be pressed evenly toward the sensor layer, thereby maintaining a stable conductive state between the terminal and the sensor layer.

[0011] In the handle according to the present invention, it is preferable that the support member is constituted by a lower cover disposed on the underside of the handle.

[0012] In this configuration, the lower cover disposed on the handle itself can be used to form a support for supporting the terminals, so there is no need to prepare a support separate from the lower cover. In addition, the screw means also functions to attach the lower cover to the core of the handle, so an increase in the number of parts required for attaching the lower cover to the core can be suppressed.

[0013] In the handle according to the present invention, the sensor layer is The mold coating agent may be formed from a urethane-based paint containing a conductive material, and may be disposed on the surface side of the coating layer when the coating layer is molded.

[0014] In this configuration, the sensor layer formed as a coating film is a mold coat layer (in-mold coat layer), and the mold coating agent made of a urethane-based paint containing a conductive material is applied in advance to the mold surface of the mold used to mold the coating layer, and then the coating layer is simply molded to easily form the coating layer provided with the sensor layer. Furthermore, as a comparative example, for example, in a case where the sensor layer is not made into a mold coat layer, but a urethane-based paint containing a conductive material for forming the sensor layer is applied to the outer surface side of the coating layer after molding and then cured to form the sensor layer, a primer is applied to the outer surface of the coating layer after molding, or a drying process after applying the urethane-based paint is required. Compared to this case, the handle provided with the sensor layer made of the mold coat layer of the present invention can be easily manufactured because the primer application process and drying process described above are not required. [Brief description of the drawings]

[0015] [Figure 1] FIG. 2 is a schematic plan view showing a handle of one embodiment of the present invention. [Diagram 2] 2 is a schematic cross-sectional view of a gripping portion of the handle of the embodiment, which corresponds to the portion II-II in FIG. 1. [Diagram 3] 1A to 1C are diagrams illustrating a manufacturing process of the handle according to the embodiment. [Figure 4]5A to 5C are diagrams for explaining the manufacturing process of the handle according to the embodiment, showing the state after FIG. 3. [Diagram 5] 2 is a schematic cross-sectional view of a portion of the handle in the embodiment where a terminal is provided, the portion corresponding to the portion VV in FIG. 1. [Figure 6] FIG. 2 is a schematic perspective view of a terminal arrangement portion of the handle according to the embodiment. [Figure 7] 10A and 10B are diagrams illustrating an example of a state in which a terminal and a support material are joined together. [Figure 8] 13A and 13B are diagrams illustrating another state of connection between the terminal and the support member. [Figure 9] 13A and 13B are diagrams illustrating still another state of connection between the terminal and the support member. [Figure 10] 11A and 11B are diagrams illustrating other examples of conductors. [Figure 11] FIG. 11 is a schematic cross-sectional view of a gripping portion of a modified example of the embodiment. [Figure 12] 12A to 12C are diagrams illustrating a manufacturing process of the handle shown in FIG. [Figure 13] 12 is a diagram for explaining the manufacturing process of the handle shown in FIG. 11 , showing the state after FIG. 12 . [Figure 14] 12 is a schematic cross-sectional view of a portion of the handle shown in FIG. 11 where a terminal is provided. FIG. [Figure 15] 12 is a schematic perspective view of a portion of the handle shown in FIG. 11 where a terminal is provided. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] An embodiment of the present invention will be described below with reference to the drawings. As shown in Figs. 1 and 2, the steering wheel W1 of the embodiment is configured to include a substantially annular grip portion R1 to be gripped when steering a vehicle (not shown), a boss portion B at the center of the grip portion R1, and spoke portions S (L, R, B) connecting the grip portion R1 and the boss portion B. The spoke portion S includes spoke portions SL, SR extending from the boss portion B to both the left and right sides, and a spoke portion SB extending from the boss portion B to the rear. The steering wheel W1 is also configured to include an airbag device 100, indicated by a two-dot chain line, disposed on the upper side of the boss portion B, a steering wheel main body H1, and a lower cover 20 covering the lower side of the boss portion B.

[0017] The airbag device 100 and the lower cover 20 have substantially the same outer shape when viewed from above, and the airbag device 100 is disposed above the handle body H1, and the lower cover 20 is disposed below the handle body H1. The airbag device 100 is attached to the handle body H1 by engaging a plurality of mounting legs (not shown) with corresponding locking holes 9 of the handle body H1. The lower cover 20 is made of synthetic resin such as polypropylene, and is provided with fastening seats 21 each having a nut 22 (see FIG. 5) made of metal such as steel for fastening the screws 38, 42. The screws 38, 42 penetrating the handle body H1 are fastened to the fastening seats 21, and the handle body H1 is attached to the handle body H1. The screws 38, as described later, constitute the screw means 37, and also have the function of electrically connecting the terminal 30 to the conductive portion 14 of the sensor layer 13. The fastening seat 21 of the lower cover 20 is disposed by insert molding using the nut 22 as an insert when the lower cover 20 is molded. The nut 22 at the location where the terminal 30 is disposed becomes a female threaded portion 39 into which the screw 38 of the screw means 37 is screwed.

[0018] The handlebar body H1 is configured with a grip portion R1, a boss portion B, and a core metal 3 made of a metal material such as an aluminum alloy that connects the spoke portions S. The core metal 3 is configured with a grip core metal portion 4 disposed in the grip portion R1, a boss core metal portion 5 disposed in the boss portion B, and spoke core metal portions 6 (L, R), 7 disposed in the spoke portions S (L, R, B) so as to connect the grip core metal portion 4 and the boss core metal portion 5. The boss core metal portion 5 has a steel boss 5a disposed thereon that is connected to the steering shaft of the vehicle. The spoke core metal portion 6 is configured with spoke core metal portions 6L, 6R disposed in the left and right spoke portions SL, SR, and two spoke core metal portions 7, 7 disposed in the rear spoke portion SB, branching to the left and right at the boss core metal portion 5 side and connected to the grip core metal portion 4 side.

[0019] A grip detection circuit 25 is disposed in the boss portion B at a portion of the steering wheel main body H1 covered by the airbag device 100. Lead wires 26 extending from a sensor layer 13 described below are connected to the grip detection circuit 25, and when the driver's hand approaches the sensor layer 13 of the grip portion R1 as if gripping the grip portion R1, the capacitance increases, and the grip detection circuit 25 detects the increase and detects the driver's grip.

[0020] 2, the gripping portion R1 is composed of a gripping core bar portion 4 of the core bar 3, a covering layer 10 made of urethane foam formed by molding so as to cover the periphery of the gripping core bar portion 4, a sensor layer 13 disposed on the surface of the covering layer 10, and a protective layer 18 disposed on the surface side of the sensor layer 13. In the areas of the left and right spoke portions SL, SR that are covered by the airbag device 100, the protective layer 18 does not cover the sensor layer 13 in areas away from the gripping core bar portion 4, leaving the sensor layer 13 exposed.

[0021] The sensor layer 13 is formed from a mold coating agent 58 made of a urethane-based paint containing a conductive material (a urethane-based paint mixed with conductive carbon, metal oxide powder, etc. as a conductive filler) (see Figure 3), and is configured as a coating film that is applied to the mold surfaces 51a, 52a of the coating layer 10 during molding, and is disposed on the surface side of the coating layer 10 when the coating layer 10 is molded.

[0022] In this embodiment, the sensor layer 13 is formed from a urethane paint containing conductive carbon.

[0023] In this embodiment, the protective layer 18 is provided as a skin layer made of urethane foam that is provided by molding.

[0024] That is, in the embodiment, the urethane foam is composed of a urethane layer as a covering layer 10 on the gripping core portion 4 side on the back side of the sensor layer 13, and a urethane layer as a protective layer 18 on the front side of the sensor layer 13.

[0025] In this embodiment, the sensor layer 13 is made of a urethane-based paint containing conductive carbon, and the surface of the coating layer 10 is covered in a dark black color, while the protective layer 187 is not black, but is formed using urethane foam containing a light beige pigment to enhance the design.

[0026] In this embodiment, the thickness dimension St1 of the sensor layer 13 is set to 20 μm within a range of approximately 5 to 50 μm, preferably 10 to 30 μm, taking into consideration the conductivity, durability, and feel, and the thickness dimension Ut1 of the urethane layer of the protective layer 18 is set to 2 mm within a range of approximately 1 to 3 mm, taking into consideration the durability, feel, and sensitivity of the sensor layer 13.

[0027] 5, the lead wire 26 is connected to the sensor layer 13 by using a screw means 37 that crimps a terminal 30 connected to the tip of the lead wire 26 to the sensor layer 13(D) side. The terminal 30 is a substantially rectangular plate made of conductive metal, and is configured by providing a connecting part 32 to which the lead wire 26 is fixed by crimping at the center of the handle W1.

[0028] The portion of the steering wheel W1 where the terminal 30 is connected is located away from the area gripped by the driver and is covered by the airbag device 100, other switches, or the lower cover 20, etc., and is therefore not visible to the driver.

[0029] In the embodiment, the connection portion of the terminal 30 is disposed in a portion of the covering layer 10 that covers the lower surface side of the spoke core portion 6R, which is the portion covered by the lower cover 20. In this connection portion, a portion of the lower sensor layer 13D in the sensor layer 13(U,D) that covers the outer surface 10a side of the covering layer 10 is configured as a conductive portion 14 for electrical connection with the terminal 30, and the surface side of the conductive portion 14 is configured as a planar conductive surface 14a.

[0030] The terminal 30 is a roughly rectangular plate extending along the longitudinal direction of the spoke core portion 6R, with a connection surface 31 extending along the conductive surface 14a of the conductive portion 14 of the sensor layer 13D disposed on the upper surface 30a, and with a lower surface 30b supported by a support surface 23a on the upper surface side of a support surface portion 23 provided on the bottom wall portion 20a of the lower cover 20.

[0031] In the embodiment, the lower cover 20 serves as a support material for supporting the terminals 30. Furthermore, the support surface portion 23 is provided with locking claws 23b for assembling and holding the terminals 30. The locking claws 23b are provided to lock the front and rear edges of the terminals 30 so that the lower surfaces 30b of the terminals 30 come into contact with the support surface 23a.

[0032] An elastically deformable conductor 35 is disposed between the conductive surface 14a of the conductive portion 14 of the sensor layer 13D and the connection surface 31 of the terminal 30. In this embodiment, the conductor 35 is made of conductive rubber. In this embodiment, the conductor 35 has a width CW of about 10 mm, a thickness CT of about 5 mm, and a length CL of about 10 mm (see FIGS. 1 and 5).

[0033] The support surface portion 23 of the lower cover 20 supporting the back side of the connection surface 31 of the terminal 30, i.e., the lower surface 30b side of the terminal 30, and the portion on the core bar (spoke core bar portion 6R) side on which the conductive portion 14 of the sensor layer 13D is arranged are fastened by screw means 37 so as to approach each other.

[0034] The screw means 37 is composed of a screw 38 and a female thread portion 39 consisting of a nut 22 provided in the fastening seat 21 of the lower cover 20. The screw 38 is composed of a head 38a and a threaded rod portion 38b having a male thread portion 38c extending from the head 38a and fastened to the female thread portion 39 of the fastening seat 21. The screw 38 is fastened by inserting the threaded rod portion 38b through the insertion holes 16, 11, and 8 of the upper sensor layer 13U, the upper covering layer 10U, the spoke core portion 6R, the lower covering layer 10D, and the lower sensor layer 13D, and fastening the male threaded portion 38c at the tip to the female threaded portion 39 of the fastening seat 21, so that the head 38a presses the periphery of the insertion hole 16 of the upper sensor layer 13U and relatively pulls the fastening seat 21 into which the male threaded portion 38c is screwed upward, so that the support surface portion 23 of the lower cover 20 and the portion of the spoke core portion 6R on which the conductive portion 14 of the sensor layer 13 is disposed approach each other. At this time, the conductor 35 is compressed, and the conductive state between the conductive portion 14 of the sensor layer 13 and the terminal 30 can be stabilized.

[0035] In this embodiment, when the screw means 37 is fastened, the conductor 35 is compressed and the upper surface 21a of the fastening seat 21 and the sensor layer 13D on the lower surface side come into contact with each other.

[0036] In this embodiment, the screw means 37 having the screw 38 and the female thread portion 39 is disposed on both sides (front and rear) of the conductor 35 .

[0037] The handle body H1 of the embodiment is manufactured through a mold coating agent application step, a first urethane layer forming step as the covering layer 10, and a second urethane layer forming step as the protective layer 18.

[0038] 3A and 3B, in the mold coating agent application step, a urethane-based paint containing a conductive material for forming the sensor layer 13 is applied as mold coating agent 58 to mold surfaces 51a and 52a of split molds 51 and 52 of a mold 50 for forming a first urethane layer as the coating layer 10, by a spray gun 57 as an application device. Note that, before applying the mold coating agent 58, a release agent is applied to the mold surfaces 51a and 52a.

[0039] Next, as shown in Figures 3C and 3D as the process for molding the first urethane layer as the coating layer 10, a molding die 50 consisting of split dies 51 and 52 is clamped, and a urethane material for forming the coating layer 10 as the first urethane layer is injected into the cavity 50a and hardened, producing an intermediate molded product 53 forming the coating layer 10, and the molding die 50 is opened to remove the intermediate molded product 53.

[0040] Next, as a molding process of the second urethane layer as the protective layer 18, as shown in Fig. 4A and 4B, a mold 54 consisting of split molds 55 and 56 for molding the second urethane layer is opened, the intermediate molded product 53 is set, and the mold 54 is closed. As shown in Fig. 4B and 4C, a urethane material for molding the second urethane layer as the protective layer 18 is injected into the cavity 54a and hardened to mold the second urethane layer 18. Before molding, a mold release agent is applied to the mold surfaces 55a and 56a of the split molds 55 and 56. After molding the second urethane layer as the protective layer 18, the mold is opened and removed to obtain a molded product provided with a grip portion R1, i.e., a handle body H1.

[0041] During manufacturing (molding) of the handle body H1, insertion holes 11, 16 for inserting the threaded rod portion 38b are formed in the covering layer 10 and the sensor layer 13 at the location of the insertion hole 8 of the spoke core metal portion 6R. A through hole for inserting the threaded rod portion of the screw 42 is also formed in the left spoke core metal portion 6L.

[0042] In the steering wheel main body H1 manufactured in this manner, the screws 38, 42 are fastened to each fastening seat 21, the lower cover 20 is attached to the lower side of the boss portion B, the boss 5a of the boss portion B is fastened to the steering shaft of the vehicle, and the airbag device 100 is attached to the upper side of the boss portion B, whereby the steering wheel W1 can be assembled and mounted on the vehicle.

[0043] When the screw 38 is fastened to the fastening seat 21, the conductor 35 is placed between the conductive surface 14a of the conductive portion 14 of the sensor layer 13D and the connection surface 31 of the terminal 30, which has been placed in advance on the support surface 23a of the support surface portion 23 of the lower cover 20, using the locking claws 23b, and the threaded rod portion 38b of the screw 38 is inserted through the insertion hole 16 of the sensor layer 13(U,D), the insertion hole 11 of the coating layer 10, and the insertion hole 8 of the spoke core metal portion 6R, and the male threaded portion 38c of the threaded rod portion 38b is fastened to the female threaded portion 39 of the fastening seat 21. Then, after the lower cover 20 is attached to the underside of the handle body H1, the lead wire 26, which has been connected to the connecting portion 32, is connected to the grip detection circuit 25, which has been attached to the handle body H1. This connection results in the sensor layer 13 and a grip detection circuit 25 capable of detecting the driver's grip being connected by a lead wire 26. Furthermore, when the airbag device 100 is attached to the upper side of the boss portion B after the boss 5a of the boss portion B is fastened to the steering shaft of the vehicle, the lead wires for inputting an activation signal of the airbag device 100 extending from the vehicle side and the lead wires for power supply and output of a detection signal of the grip detection circuit 25 are connected to the airbag device 100, the grip detection circuit 25, etc.

[0044] In a steering wheel W1 mounted on a vehicle, when the driver's hand approaches the sensor layer 13 of the grip portion R1 as if gripping the grip portion R1, a specified grip detection circuit 25 detects an increase in capacitance, thereby detecting the driver's grip.

[0045] In the handle W1 of the embodiment, when the conductive portion 14 of the sensor layer 13D, the conductor 35, the connection surface 31 of the terminal 30, and the support surface portion 23 of the lower cover 20 as a support material are overlapped and the screw means 37 is tightened so as to bring the core wire 6R side and the lower cover 20 side closer together, the conductive surface 14a of the conductive portion 14 of the sensor layer 13D and the connection surface 31 of the terminal 30 are electrically connected through the conductor 35 compressed to create wide contact surfaces 35a, 35b. That is, in this fastened state, the conductor 35 acts as a cushioning material and is in intimate contact with the sensor layer 13D and the terminal 30 over a wide contact area while being interposed between the sensor layer 13D and the terminal 30. Therefore, the sensor layer 13D is configured to crimp the terminal 30 with the conductor 35 having wide contact surfaces 35a, 35b interposed therebetween so that it can follow the deformation of the soft coating layer 10 without breaking, thereby ensuring good and stable conductivity with the terminal 30.

[0046] Therefore, in the handle W1 of the embodiment, the coating-like sensor layer 13 for grip detection and the terminals 30 can be stably connected, enabling good grip detection.

[0047] In addition, in the handle W1 of the embodiment, the sensor layer 13 is formed from a mold coating agent 58 made of a urethane-based paint containing a conductive material, and is configured to be disposed on the surface (outer surface) 10a side of the coating layer 10 when the coating layer 10 is molded (see Figures 2 and 3).

[0048] Therefore, in the embodiment, the sensor layer 13 formed as a coating film is the mold coat layer (in-mold coat layer) 15, and the mold coat agent 58 made of a urethane-based paint containing a conductive material is applied in advance to the mold surfaces 51a, 52a of the mold 50 when the coating layer 10 is molded, and the coating layer 10 provided with the sensor layer 13 can be formed by simply molding the coating layer 10. Furthermore, as a comparative example, for example, in a case where the sensor layer is not made into a mold coat layer, but a urethane-based paint containing a conductive material for forming the sensor layer is applied to the outer surface 10a side of the coating layer 10 after molding and then cured to form the sensor layer, a primer is applied to the outer surface of the coating layer after molding, or a labor for drying after applying the urethane-based paint is required. Compared to this case, the handle W1 provided with the sensor layer 13 made of the mold coat layer of the embodiment can be easily manufactured because the above-mentioned primer application process and drying process are not required.

[0049] Of course, if the above points are not taken into consideration, the sensor layer may not be a mold coat layer, but may be formed by applying a urethane-based paint containing a conductive material for forming the sensor layer to the outer surface side of the molded covering layer and then curing it.

[0050] Furthermore, in the handle W1 of this embodiment, the screw means 37 are disposed on both sides in the front-rear direction with the conductor 35 therebetween.

[0051] Therefore, in the embodiment, since screw means 37 are arranged on both sides of the conductor 35, when the conductor 35 is compressed, the conductive surface 14a of the sensor layer 13D and the connection surface 31 of the terminal 30 can be brought closer to each other while maintaining a parallel state, so that the terminal 30 can be evenly pressed toward the sensor layer 13D, and a stable conductive state between the terminal 30 and the sensor layer 13D can be maintained.

[0052] In the handle W1 of the embodiment, the support member for supporting the terminal 30 is constituted by the lower cover 20 disposed on the lower surface side of the handle W1.

[0053] Therefore, in the embodiment, the lower cover 20 disposed on the handle W1 itself can be used to configure a support material for supporting the terminal 30, so there is no need to prepare a support material separate from the lower cover 20. In addition, the screw means 37 also functions to attach the lower cover 20 to the core 3 (spoke core portion 6R) of the handle W1, so an increase in the number of parts such as the mounting screws 38, 42 for the lower cover 20 can be suppressed.

[0054] The screw means 37 may not necessarily be composed of the screw 38 for inserting the insertion holes 16, 8, 11 from the sensor layer 13U and the female screw portion 39 for screwing the male screw portion 38c from the sensor layer 13U, as in the embodiment, because it is sufficient to fasten the conductor 35 disposed between the conductive surface 14a of the sensor layer 13D and the connection surface 31 of the terminal 30 to the lower cover 20 as a support material for supporting the terminal 30 by compressing the conductor 35 so as to exert a repulsive force. For example, the screw 38 may be inserted through the insertion holes 16, 8, 11 from the sensor layer 13U, and fastened with a nut on the lower surface of the lower cover 20 without providing the female screw portion 39, or a bolt may be insert-molded on the support material side so as to extend upward, and the bolt may be inserted through the insertion holes 16, 8, 11 from the sensor layer 13D side, and fastened with a nut on the upper sensor layer 13U side. Furthermore, the nut 22 may not be provided, and the female thread portion 39 may be threaded into the fastening seat 21 of the lower cover 20 .

[0055] The lower cover 20 as a support material for supporting the terminal 30 may be provided by adhering the terminal 30 to the lower cover 20, or as shown in Fig. 7, when the lower cover 20A is formed using a molding die 44 having split dies 44a, 44b, the lower cover 20A may be insert-molded with the terminal 30A as an insert, and the terminal 30A may be provided in the lower cover 20A. Alternatively, as shown in Fig. 8, a protrusion 23c for thermal crimping may be provided protruding from the support surface portion 23 of the lower cover 20B, and the protrusion 23c may be inserted into the mounting hole 33 of the terminal 30B, and the tip of the protrusion 23c may be melted so as to expand its diameter, so that the terminal 30B is engaged with the support surface portion 23. Alternatively, as shown in FIG. 9, a mounting hole 33C for inserting a screw 46 may be provided in the terminal 30C, and the screw 46 may be inserted through the mounting hole 33C and screwed into the screw hole 23d of the support surface portion 23, thereby arranging the terminal 30C on the support surface portion 23.

[0056] Furthermore, as the elastically deformable conductor 35, in addition to the conductive rubber as in the embodiment, as long as it is compressed and a wide contact surface 35a can be secured with respect to the sensor layer 13D, as shown in FIG. 10, a conductor 35D made of a conductive metal spring or a conductive cloth (not shown) having elastically deformable conductivity can be used.

[0057] The conductors 35, 35D may be previously attached to the terminal 30 as long as they are elastically deformable while maintaining a good electrical connection.

[0058] In order to improve the sensitivity of the sensor layer 13, a shield layer 64 may be disposed around the core bar (gripping core bar portion) 4 as in the handle W2 shown in FIGS.

[0059] As shown in Fig. 11, the grip part R2 of the handle W2 includes the grip core part 4 of the core 3, a covering layer 60 made of urethane foam arranged by molding so as to cover the periphery of the grip core part 4, and a sensor layer 67. As in the embodiment, the sensor layer 67 is formed from a mold coating agent 85 made of a urethane paint containing a conductive material (conductive carbon) (see Fig. 13), and is applied to the mold surfaces 78a, 79a of the second urethane layer 62 of the covering layer 60 during molding, and is arranged on the surface side of the second urethane layer 62 when the second urethane layer 62 of the covering layer 60 is molded. Furthermore, the sensor layer 67 is arranged covered with a protective layer 70 arranged on the surface side.

[0060] The covering layer 60 made of foamed urethane is configured to include a first urethane layer 61 on the gripping core bar portion 4 side of the core bar 3, a second urethane layer 62 on the back side of the sensor layer 67, and a shielding layer 64 arranged between the first urethane layer 61 and the second urethane layer 62.

[0061] The shield layer 64 is made of a first mold coating agent 84 (see FIG. 12) made of a urethane-based paint containing a conductive material (e.g., conductive carbon). The sensor layer 67 is made of a second mold coating agent 85 (see FIG. 13). That is, the first mold coating agent 84 is applied to the mold surfaces 74a, 75a of the mold 73 for the first urethane layer 61 during molding, and is disposed on the surface side of the first urethane layer 61 during molding of the first urethane layer 61, forming the first mold coating layer 65. The second mold coating agent 85 for forming the sensor layer 67 is applied to the mold surfaces 78a, 79a of the mold 77 for the second urethane layer 62 during molding, and the sensor layer 67, which becomes the second mold coating layer 68, is disposed on the surface side of the second urethane layer 62 during molding of the second urethane layer 62.

[0062] The handle body H2 of the handle W2 is manufactured through a shield mold coating agent application step, a first urethane layer molding step, a sensor mold coating agent application step, a second urethane layer molding step, and a protective layer molding step.

[0063] 12A and 12B, in the shielding mold coating agent application process, a urethane paint containing a conductive material for forming the shield layer 64 is applied as a first mold coating agent 84 by a spray gun 81 as an application device to mold surfaces 74a, 75a of split molds 74, 75 of a molding die 73 for forming a first urethane layer 61 as a covering layer 60. Before applying the mold coating agent 84, a release agent is applied to the mold surfaces 74a, 75a.

[0064] Next, as the first urethane layer molding process, as shown in Figure 12B and C, a molding die 73 consisting of split dies 74, 75 is clamped, a urethane material for forming the first urethane layer 61 is injected into the cavity 73a and hardened, an intermediate molded product 66 is produced by molding the first urethane layer 61, and the molding die 73 is opened to remove the intermediate molded product 66.

[0065] 13A, a urethane-based paint containing a conductive material for forming the sensor layer 67 is applied as a second mold coating agent 85 to mold surfaces 78a, 79a of split molds 78, 79 of a mold 77 for forming the second urethane layer 62 as the covering layer 60 by a spray gun 82 as an application device. Before applying the mold coating agent 85, a release agent is applied to the mold surfaces 78a, 79a.

[0066] 13A and 13B, in the second urethane layer molding step, intermediate molded product 66 is set in mold 77 consisting of split molds 78 and 79 for molding second urethane layer 62, mold 77 is closed, and urethane material for molding second urethane layer 62 is injected into cavity 77a and hardened to form second urethane layer 62. Then, after molding second urethane layer 62, the mold is opened and removed to obtain intermediate molded product 69 before molding protective layer 70 (see C in FIG. 13).

[0067] Thereafter, by forming a protective layer 70 on the intermediate molded product 69, the grip portion R2 of the handle body H2 can be manufactured (see D in FIG. 13).

[0068] It should be noted that, when the handle body H2 is molded, the insertion holes of the spoke core portion 6L through which the screws 38 of the screw means 37 are inserted are provided with insertion holes (not shown) of the covering layer 60, the sensor layer 67, and the shield layer 64, through which the screws 38 can be inserted, as in the embodiment.

[0069] With the steering wheel main body H2 manufactured in this manner, similarly to the steering wheel main body H1, the lower cover 20E is attached to the lower side of the boss portion B, the boss 5a of the boss portion B is fastened to the steering shaft of the vehicle, and the airbag device 100 is attached to the upper side of the boss portion B, whereby the steering wheel W2 can be assembled and mounted on the vehicle.

[0070] The lead wire 87 connected to the shield layer 64 is connected to a predetermined shield circuit connected to the grip detection circuit, and is joined to a connecting portion 92 of a terminal 90, and the terminal 90 has a connection surface 91 pressed against a conductor 35E made of conductive rubber. The sensor layer 67 is also connected to the terminal 30E via the conductor 35E, as in the embodiment. [Explanation of symbols]

[0071] 3...core metal, 6 (L, R)...spoke core metal portion, 10 (U, D), 60...coating layer, 13 (U, D), 67...sensor layer, 14...conductive portion, 14a...conductive surface, 20, 20A, 20B, 20C, 20E...(support material) lower cover, 25...grip detection circuit, 26...lead wire, 30, 30A, 30B, 30C, 30E...terminal, 31...connection surface, 35, 35A, 35D, 35E...conductor, 37...screw means, 38...screw, 39...female thread portion, H1, H2...Handle body, R1, R2...Grip part, W1, W2...Handle.

Claims

1. A sensor layer made of a coating film containing a conductive material is disposed on a surface side of a soft coating layer disposed around a core metal so that the gripping of the steering wheel during steering can be detected. The sensor layer is a handle for connecting a terminal of a lead wire that is connected to a grip detection circuit for detecting a grip, the sensor layer disposed on the surface side of the coating layer covering the core metal has a flat conductive surface at a conductive portion with the terminal, The terminal is formed in a plate shape having a connection surface along the conductive surface, an elastically deformable conductor is disposed between the conductive surface and the connection surface; a screw means for fastening a support member for supporting a rear side of the connection surface of the terminal and a portion of the sensor layer on the side of the core metal, the portion having the conductive portion disposed thereon, so as to bring them closer to each other; The present invention is configured with A handle as claimed in any one of claims 1 to 5, wherein said screw means is disposed on either side of said conductor.

2. A sensor layer made of a coating film containing a conductive material is disposed on a surface side of a soft coating layer disposed around a core metal so that the gripping of the steering wheel during steering can be detected. The sensor layer is a handle for connecting a terminal of a lead wire that is connected to a grip detection circuit for detecting a grip, the sensor layer disposed on the surface side of the coating layer covering the core metal has a flat conductive surface at a conductive portion with the terminal, The terminal is formed in a plate shape having a connection surface along the conductive surface, an elastically deformable conductor is disposed between the conductive surface and the connection surface; a screw means for fastening a support member for supporting a rear side of the connection surface of the terminal and a portion of the sensor layer on the side of the core metal, the portion having the conductive portion disposed thereon, so as to bring them closer to each other; The present invention is configured with A handle characterized in that the support member is constituted by a lower cover disposed on the underside of the handle.

3. A sensor layer made of a coating film containing a conductive material is disposed on a surface side of a soft coating layer disposed around a core metal so that the gripping of the steering wheel during steering can be detected. The sensor layer is a handle for connecting a terminal of a lead wire that is connected to a grip detection circuit for detecting a grip, the sensor layer disposed on the surface side of the coating layer covering the core metal has a flat conductive surface at a conductive portion with the terminal, The terminal is formed in a plate shape having a connection surface along the conductive surface, an elastically deformable conductor is disposed between the conductive surface and the connection surface; a screw means for fastening a support member for supporting a rear side of the connection surface of the terminal and a portion of the sensor layer on the side of the core metal, the portion having the conductive portion disposed thereon, so as to bring them closer to each other; The present invention is configured with A handle characterized in that the sensor layer is formed from a mold coating agent made of a urethane-based paint containing a conductive material, and is disposed on the surface side of the coating layer when the coating layer is molded.

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