Steering system

Abstract

The present invention provides a steering device that can firmly attach a circuit board to a pad, even when the pad's protrusion is short and its outer diameter is small. [Solution] The steering wheel 10 as a steering device comprises a pad 5 having illuminated parts 5x1 to 5x5 and protruding parts 5a2a to 5a2d that protrude forward from the front surface of the pad 5, a circuit board 52 on which LEDs 53a to 53e that emit light to illuminate the illuminated parts 5x1 to 5x5 are mounted, and a holder member 55 positioned in front of the pad 5 and holding the circuit board 52, having through holes 55d1 to 55d4 through which the protruding parts 5a2a to 5a2d are inserted, and connecting walls 55e1 to 55e4 that extend forward from the periphery of the insertion holes 55d1 to 55d4 so as to cover the side surfaces 5a2a1 to 5a2d1 of the protruding parts 5a2a to 5a2d and to which the protruding parts 5a2a to 5a2d are welded.

Description

Technical Field

[0001] The present invention relates to a steering device mounted on a vehicle.

Background Art

[0002] Conventionally, in order to decorate a steering device, a configuration in which a lighting portion is provided on a pad of the steering device is widely known. For example, in Patent Document 1, a steering device is disclosed that includes a pad having a lighting portion and a substrate mounted on the front surface (back surface) of the pad and emitting light for lighting the lighting portion.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the configuration of Patent Document 1, after inserting the tip of a protruding portion that protrudes forward from the front surface of the pad into an insertion hole formed in the substrate, the substrate is attached to the pad by welding the tip of the protruding portion to the substrate. However, depending on the arrangement of the members around the protruding portion, it may be necessary to set the outer diameter of the protruding portion of the pad to be small.

[0005] In that case, if the protruding portion is not lengthened, the amount of melting during welding of the protruding portion will be reduced, and the mounting strength of the substrate to the pad will decrease. On the other hand, if the protruding portion is made slender, the protruding portion is likely to break, leading to a decrease in assembly workability and a deterioration in yield.

[0006] Therefore, an object of the present invention is to provide a steering device capable of firmly attaching a substrate to a pad even when the protruding portion of the pad is short and the outer diameter is small. [Means for solving the problem]

[0007] A typical configuration of the steering device according to the present invention for solving the above problems is a steering device mounted on a vehicle, comprising: a boss portion connected to the steering shaft of the vehicle; a pad covering the boss portion from the rear, having a light-emitting portion and a protruding portion projecting forward from the front surface of the pad; a substrate on which a light source that emits light for illuminating the light-emitting portion is mounted; and a holding member positioned in front of the pad and holding the substrate, having a through hole through which the protruding portion is inserted, and a connecting wall extending forward from the periphery of the insertion hole so as to cover the side surface of the protruding portion, to which the protruding portion is welded.

[0008] According to the steering device of the present invention, even when the protruding portion of the pad is short and the outer diameter is small, the substrate can be firmly attached to the pad. [Brief explanation of the drawing]

[0009] [Figure 1] This is a view from the left side of the area around the driver's seat of a vehicle equipped with a steering wheel. [Figure 2] This is a front view of the steering wheel. [Figure 3] This is a front view of the steering wheel with the airbag inflated. [Figure 4] This is a cross-sectional view of the steering wheel taken along the AA section shown in Figure 2. [Figure 5] This is a perspective view of the optical unit. [Figure 6] This is a front view of the optical unit and pad. [Figure 7] This is a disassembled perspective view of the optical unit and pads. [Figure 8] This is a disassembled perspective view of the optical unit and pads. [Figure 9] This is a disassembled perspective view of the pads of the optical unit. [Figure 10]This is a magnified cross-sectional view of the area around the lighting and optical unit of the steering wheel. [Figure 11] This is a magnified cross-sectional view of the area around the lighting and optical unit of the steering wheel. [Modes for carrying out the invention]

[0010] The configuration of the steering wheel 10 as a steering device according to one embodiment of the present invention will be described below with reference to the drawings. Note that the dimensions, materials, shapes, and relative arrangements of the components described below are not intended to limit the scope of this invention to those unless otherwise specifically stated.

[0011] Figure 1 is a view from the left side of the area around the driver's seat 39 of a vehicle 30 equipped with a steering wheel 10, with the driver M seated in the driver's seat 39 indicated by a dashed line. Figure 2 is a front view of the steering wheel 10. Figure 3 is a front view of the steering wheel 10 with the airbag 41 inflated. Figure 4 is a cross-sectional view of the steering wheel 10 cut along the cross-section AA shown in Figure 2.

[0012] In the following explanation, unless otherwise specified, each direction described with respect to the steering wheel 10 refers to the direction when the steering wheel 10 is mounted on the vehicle 30 as shown in Figure 1. That is, the front-rear direction generally coincides with the direction of travel and the opposite direction when the vehicle 30 is traveling straight, or the front and rear directions as seen from the driver M. The left-right direction refers to the left and right directions when the vehicle 30 is traveling straight, specifically the left and right directions as seen from the driver M. The up-down direction generally coincides with the up and down directions in the vertical direction.

[0013] As shown in FIG. 1, the steering wheel 10 (steering device) is mounted on the vehicle 30 by being connected to the steering shaft 35 (steering axis) of the vehicle 30. The vehicle 30 includes a steering column 36 that partially covers the outer peripheral portion of the steering shaft 35 to support the steering shaft 35, and a column cover 36b that covers a portion of the steering shaft 35 protruding rearward from the instrument panel 37. The steering wheel 10 is attached to the rear end portion 35a of the steering shaft 35 protruding rearward from the instrument panel 37.

[0014] As shown in FIGS. 2 to 4, the steering wheel 10 includes a grip portion 1 that is gripped by the driver M during steering of the vehicle 30, a boss portion 2 that is connected to the steering shaft 35, and a spoke portion 3 that connects the grip portion 1 and the boss portion 2. Further, the steering wheel 10 includes a pad 5 that covers the boss portion 2 and the folded airbag 41 from the rear and constitutes a part of the exterior on the rear side of the steering wheel 10, and an optical unit 50 that is attached to the front surface (rear surface) of the pad 5 and lights up the lighting portions 5x1 to 5x5 of the pad 5. Further, the steering wheel 10 includes a lower cover 6 that constitutes the exterior on the front side thereof, and an airbag unit 40 that is disposed between the boss portion 2 and the pad 5 and includes the airbag 41.

[0015] The grip portion 1 is composed of a metal core material 1a, an intermediate material 1b made of a synthetic resin such as polyurethane that covers the core material 1a, and a surface material 1c such as leather wound around the outer peripheral portion of the intermediate material 1b. The driver M rotates the steering shaft 35 by gripping and rotating the grip portion 1 to change the traveling direction of the vehicle 30.

[0016] The boss portion 2 is a metal member connected to the steering shaft 35 and has a shaft hole 2a through which the steering shaft 35 is inserted. The steering shaft 35 is inserted into the shaft hole 2a and fitted, and then the two are fixed with a nut 38, whereby the boss portion 2 and the steering shaft 35 are connected.

[0017] The spoke portion 3 is composed of a left spoke portion 3a and a right spoke portion 3b that respectively extend left and right from the boss portion 2, and a lower spoke portion 3c that extends downward. The spoke portion 3 has a metal core 3x1 that connects the core 1a of the grip portion 1 and the boss portion 2, and a resin spoke cover 3x2 that covers the core 3x1. The core 1a of the grip portion 1, the boss portion 2, and the core 3x1 of the spoke portion 3 are integrally formed by die-casting.

[0018] The pad 5 is formed of an olefin-based thermoplastic elastomer (:TPO), which is a synthetic resin in this embodiment. The pad 5 has a cover portion ⑤a that covers the rear of the folded airbag 41 and constitutes a part of the exterior of the steering wheel 10, and a connecting portion 5b that extends forward from the cover portion 5a and is connected to the case 43 of the airbag unit 40. An insertion hole 5b1, which is a through hole penetrating in the left-right direction, is formed in the lower part of the connecting portion 5b.

[0019] The cover portion 5a of the pad 5 breaks due to the pressure received from the airbag 41 when the airbag 41 expands, forming an opening 5h, and the airbag 41 is fed out from the opening 5h. The cover portion 5a has a substantially rectangular door portion 5ad that rotates upward when broken. When the airbag 41 expands and contacts the door portion 5ad, and the door portion 5ad rotates as described above, an opening 5h is formed in the cover portion 5a. Note that the edge portion of the door portion 5ad in the cover portion 5a is a vulnerable portion (not shown) that is cut out from the back surface 5az2 side of the cover portion 5a to be thin-walled so as to be easily broken by the pressure received from the airbag 41.

[0020] Furthermore, the cover portion 5a is provided with five illuminated sections 5x1 to 5x5 arranged in parallel in the left-right direction, which light up as decoration for the pad 5. In this embodiment, all of the illuminated sections 5x1 to 5x5 light up to display the letter "S". However, the present invention is not limited to this, and may be configured in other ways, such as a configuration in which each of the illuminated sections 5x1 to 5x5 lights up to display a different letter, a configuration in which they light up to display other types of characters such as katakana or Arabic characters, or a configuration in which they light up in other shapes such as dots.

[0021] Furthermore, an optical unit 50, which includes a light source for illuminating the lighting units 5x1 to 5x5, is attached to the back surface 5az2 (front surface of the pad) of the cover portion 5a. The detailed configuration of the lighting units 5x1 to 5x5 and the optical unit 50 will be described later. Note that since the optical unit 50 is attached to the back surface of the door portion 5ad of the cover portion 5a, it rotates upward together with the door portion 5ad as the airbag 41 inflates, so as not to adversely affect the inflation of the airbag 41.

[0022] The airbag unit 40 comprises an airbag 41, an inflator 42 that supplies inflation gas to the airbag 41, a case 43 that holds the airbag 41 and the inflator 42, and a retainer 44 housed inside the airbag 41.

[0023] The inflator 42 is a substantially cylindrical member that generates and releases expansion gas, and has a discharge port 42a on its rear side for discharging the expansion gas. The portion of the inflator 42 where the discharge port 42a is formed is located inside the airbag 41. The inflator 42 also has a flange portion 42b that extends radially from the surface where the discharge port 42a is formed, as a portion that connects to the case 43. The inflator 42 is electrically connected to a control device (not shown), and operates to generate expansion gas when a signal is input from the control device.

[0024] The airbag 41 is a bag-shaped component made of synthetic fibers or the like, and is stored inside the steering wheel 10 in a folded state. At the front of the folded airbag 41, there is a gas inlet 41h, which is an opening for inserting the portion where the discharge port 42a of the inflator 42 is formed. When fully inflated, the airbag 41 is configured to cover the entire gripping portion 1 of the steering wheel 10 from the rear.

[0025] The case 43 is a sheet metal component that holds the airbag 41, the inflator 42, and the pad 5. The case 43 is fixed to the core material 3x1 of the spoke portion 3 via a pin of a horn switch unit (not shown). The case 43 has a bottom wall portion 43a which is rectangular and has an insertion hole 43a1 through which the inflator 42 is inserted, and a side wall portion 43b which extends rearward from the outer edge of the bottom wall portion 43a. The pad 5 is held in the case 43 by the bottom wall portion 43a being inserted through the insertion hole 5b1 of the connecting portion 5b of the pad 5 and being prevented from coming out by the side wall portion 43b.

[0026] The retainer 44 is a roughly rectangular, annular metal member used to secure the airbag 41 and the like, and is positioned inside the airbag 41. The retainer 44 has a through hole 44a through which the inflator 42 is inserted. When securing the airbag 41 and the inflator 42 to the case 43, the inflator 42 is inserted through the through hole 43a1 of the case 43, the gas inlet 41h of the airbag 41, and the through hole 44a of the retainer 44. Bolts 45 are then inserted through screw holes formed on the periphery of the gas inlet 41h of the airbag 41, the bottom wall portion 43a of the case 43, and the flange portion 42b of the inflator 42, respectively, and fastened with nuts 46. As a result, the periphery of the gas inlet 41h of the airbag 41 is sandwiched between the front surface of the retainer 44 and the rear surface of the bottom wall 43a of the case 43, and the flange portion 42b of the inflator 42 is sandwiched between the front surface of the bottom wall 43a and the nut 46. In this way, the airbag 41 and the inflator 42 are fixed to the bottom wall 43a of the case 43.

[0027] Next, the detailed configuration of the lighting sections 5x1 to 5x5 of the pad 5 and the optical unit 50 will be described. Figure 5 is a perspective view of the optical unit 50. Figure 6 is a front view of the optical unit 50 and the pad 5. Figures 7 and 8 are exploded perspective views of the optical unit 50 and the pad 5 as seen from the front side, with Figure 8 showing the circuit board 52 and the light guide 54 assembled to the holder member 55. Figure 9 is an exploded perspective view of the optical unit 50 and the pad 5 as seen from the back side. Figure 10 is an enlarged cross-sectional view of the area around the lighting sections 5x1 to 5x5 and the optical unit 50 in the steering wheel 10.

[0028] As shown in Figures 5 to 10, the optical unit 50 comprises an emblem 51, a circuit board 52, five LEDs 53a to 53e mounted on the circuit board 52, a light guide 54 that guides the light emitted from the five LEDs 53a to 53e, and a holder member 55. These components are arranged in the order of emblem 51, light guide 54, circuit board 52 on which the LEDs 53a to 53e are mounted, and holder member 55, from front to back.

[0029] The cover portion 5a of pad 5 has five through holes 5a1a to 5a1e, each cut out in the shape of the letter "S" and extending through in the front-to-back direction, arranged side by side in the left-to-right direction. Additionally, the back surface 5az2 (front) of the cover portion 5a of pad 5 has four protrusions 5a2a to 5a2d that project forward, arranged side by side in the left-to-right direction. All of the protrusions 5a2a to 5a2d are the same shape and are integrally molded with the cover portion 5a of pad 5.

[0030] As will be explained later, the light unit 5x1 of pad 5 is lit by light irradiated from behind pad 5 through the through hole 5a1a, so the light unit 5x1 can also be seen as the through hole 5a1a. Similarly, the light unit 5x2 can be seen as the through hole 5a1b, the light unit 5x3 as the through hole 5a1c, the light unit 5x4 as the through hole 5a1d, and the light unit 5x5 as the through hole 5a1e.

[0031] The emblem 51 is a material that has high light transmittance throughout and is attached to the back surface 5az2 of the cover portion 5a of the pad 5. The emblem 51 has a substantially rectangular base portion 51a and side wall portions 51b that extend forward from each side of the base portion 51a.

[0032] The base 51a of the emblem 51 has five projections 51a1a to 51a1e that protrude backward in shapes corresponding to the display characters 5x1 to 5x5 of the illuminated section 5. Specifically, projections 51a1a, 51a1b, 51a1c, 51a1d, and 51a1e all protrude in the shape of the letter "S". Furthermore, projections 51a1a to 51a1e are arranged in parallel in the left-right direction.

[0033] The projections 51a1a to 51a1e are fitted from the front into the through holes 5a1a to 5a1e of the pad 5 so as to fill the through holes 5a1a to 5a1e. In this embodiment, the rear ends of the projections 51a1a to 51a1e are located in front of the surface 5az1 (rear surface of the pad) of the cover portion 5a of the pad 5. That is, as viewed from the driver M, the projections 51a1a to 51a1e are located slightly recessed from the through holes 5a1a to 5a1e. However, the projections 51a1a to 51a1e may be configured to be flush with the surface 5az1 of the cover portion 5a, or to protrude rearward from the surface 5az1.

[0034] Furthermore, in the base portion 51a of the emblem 51, between the left-right adjacent protrusions 51a1a and 51a1b, there is an insertion hole 51a2a that penetrates in the front-rear direction, through which the protruding portion 5a2a of the pad 5 is inserted. Similarly, in the base portion 51a, between the protrusions 51a1b and 51a1c, between the protrusions 51a1c and 51a1d, and between the protrusions 51a1d and 51a1e, there is an insertion hole 51a2b to 51a2d through which the protruding portions 5a2b to 5a2d of the pad 5 are inserted.

[0035] Furthermore, the side wall portion 51b of the emblem 51 is provided with two claw portions 51b1 that protrude forward. In addition, the inner surface of the side wall portion 51b of the emblem 51 is provided with two positioning protrusions 51b2 that protrude in a V-shape in the left-right direction. In this embodiment, one claw portion 51b1 and one positioning protrusion 51b2 are each arranged on the side wall portion 51b that extends forward from the two short sides of the base portion 51a. However, the present invention is not limited to this, and the claw portions 51b1 and positioning protrusions 51b2 may be provided on the base portion 51a or other side wall portions 51b.

[0036] The circuit board 52 (substrate) is a rectangular parallelepiped-shaped component that is wide from left to right. The rear surface of the circuit board 52 is the mounting surface 52a, on which five LEDs 53a to 53e and a control component 57 such as a CPU that controls the lighting of LEDs 53a to 53e are mounted. LEDs 53a to 53e are arranged in a left-right direction on the mounting surface 52a and each emits visible light according to the control of the control component 57. Here, LED 53a is a light source that emits light to light up the lighting section 5x1 of the pad 5. Similarly, LED 53b is a light source that emits light to light up the lighting section 5x2 of the pad 5. Likewise, LEDs 53c to 53e are light sources that emit light to light up the lighting sections 5x3 to 5x5 of the pad 5, respectively. In this embodiment, LEDs 53a to 53e are used as light sources, but other light sources may be used as long as they are components that emit visible light. For example, an organic EL held on the substrate may be used as another light source.

[0037] Furthermore, the right and left ends of the circuit board 52 are provided with V-shaped positioning grooves 52b. The emblem 51 and the circuit board 52 are positioned by fitting the positioning projections 51b2 of the emblem 51 into the positioning grooves 52b. The circuit board 52 also has through holes 52c1 to 52c4 (board insertion holes) through which the protrusions 5a2a to 5a2d of the pads 5 are inserted.

[0038] The light guide 54 is a synthetic resin component positioned in front of the emblem 51 that guides the light emitted from the LEDs 53a to 53e while diffusing it internally. The light emitted downward from the LEDs 53a to 53e enters the upper surface of the light guide 54, is deflected by a deflection section (not shown), and is emitted forward from the front surface of the light guide 54.

[0039] Specifically, light emitted from LED 53a enters the incident surface 54a1 of the light guide 54 and is emitted from the exit surface 54b1, which is positioned to correspond to the protrusion 51a1a of the emblem 51. Similarly, light emitted from LED 53b enters the incident surface 54a2 of the light guide 54 and is emitted from the exit surface 54b2, which is positioned to correspond to the protrusion 51a1b of the emblem 51. Light emitted from LEDs 53c to 53e also enters the incident surfaces 54a3 to 54a5 of the light guide 54, respectively, and is emitted from the exit surfaces 54b3 to 54b5, which are positioned to correspond to the protrusions 51a1c to 51a1e of the emblem 51. In this embodiment, the deflection portion is a textured surface formed on the light guide 54, and the light is deflected by reflecting the light off the inner wall of the textured surface.

[0040] Furthermore, the right and left ends of the light guide 54 are provided with V-shaped positioning grooves 54c. The emblem 51 and the light guide 54 are positioned by fitting the positioning projections 51b2 of the emblem 51 into the positioning grooves 54c. The light guide 54 is also provided with through holes 54d1 to 54d4 that penetrate in the front-to-back direction, through which the protrusions 5a2a to 5a2d of the pad 5 are inserted.

[0041] The holder member 55 (holding member) is a synthetic resin member positioned in front of the circuit board 52, and its outer shape is a roughly rectangular parallelepiped that is wide in the left-right direction. In this embodiment, the holder member 55 is made of olefin-based thermoplastic elastomer (TPO), which is the same material as the pad 5. The holder member 55 includes a mounting portion 55a on which the circuit board 52 is placed, and two engagement holes 55b that are positioned near the left-right edges of the mounting portion 55a and penetrate in the front-rear direction, with the two claw portions 51b1 of the emblem 51 engaging with each other.

[0042] The claw portion 51b1 of the emblem 51 engages with the engagement hole 55b of the holder member 55, thereby connecting the holder member 55 and the emblem 51. This forms a box-shaped housing that houses the circuit board 52 on which the light guide 54 and LEDs 53a to 53e are mounted. Specifically, the front of the housing is the holder member 55, the rear is the base portion 51a of the emblem 51, and the four sides are the side walls 51b of the emblem 51.

[0043] Furthermore, the holder member 55 has a through hole 55d1 that penetrates in the front-rear direction through which the protrusions 5a2a of the pad 5 are inserted, and a cylindrical connecting wall 55e1 that extends forward from the periphery of the through hole 55d1 to cover the side surface 5a2a1 of the protrusions 5a2a, to which the protrusions 5a2a are welded. The holder member 55 also has a cylindrical partition wall 55f1 that extends rearward from the periphery of the through hole 55d1 to cover the side surface 5a2a1 of the protrusions 5a2a, and is positioned between the inner circumferential portion 52c1a of the through hole 52c1 of the circuit board 52, the inner circumferential portion 54d1a of the through hole 54d1 of the light guide 54, and the inner circumferential portion 51a2a1 of the through hole 51a2a of the emblem 51 and the side surface 5a2a1 of the protrusions 5a2a. In other words, the partition wall 55f1 is inserted through the insertion hole 52c1 of the circuit board 52, the insertion hole 54d1 of the light guide 54, and the insertion hole 51a2a of the emblem 51.

[0044] Furthermore, the rear end of the partition wall 55f1 is in contact with the back surface 5az2 of the cover portion 5a of the pad 5. In addition, the side surface of the partition wall 55f1 is in contact with the inner circumference 52c1a of the insertion hole 52c1 of the circuit board 52, the inner circumference 54d1a of the insertion hole 54d1 of the light guide 54, and the inner circumference 51a2a1 of the insertion hole 51a2a of the emblem 51.

[0045] Similarly, the holder member 55 has through holes 55d2 to 55d4 that penetrate in the front-rear direction, through which the protrusions 5a2b to 5a2d of the pad 5 are inserted, and cylindrical connecting walls 55e2 to 55e4 that extend forward from the respective peripheries of the insertion holes 55d2 to 55d4 so as to cover the side surfaces 5a2b1 to 5a2d1 of the protrusions 5a2b to 5a2d, to which the protrusions 5a2b to 5a2d are welded. Furthermore, the holder member 55 extends rearward from the respective periphery of the insertion holes 55d2 to 55d4 so as to cover the side surfaces 5a2b1 to 5a2d1 of the protrusions 5a2b to 5a2d, and has cylindrical partition walls 55f2 to 55f4 positioned between the inner circumferential portions 52c2 to 52c4 of the circuit board 52, the inner circumferential portions 54d2a to 54d4a of the insertion holes 54d2 to 54d4 of the light guide 54, and the side surfaces 5a2b1 to 5a2d1 of the insertion holes 51a2b to 51a2d of the emblem 51. In other words, the partitions 55f2 to 55f4 are inserted through the through holes 52c2 to 52c4 of the circuit board 52, the through holes 54d2 to 54d4 of the light guide 54, and the through holes 51a2b to 51a2d of the emblem 51.

[0046] Furthermore, the rear ends of the partition walls 55f2 to 55f4 are in contact with the back surface 5az2 of the cover portion 5a of the pad 5. In addition, the sides of the partition walls 55f2 to 55f4 are in contact with the inner circumference portions 52c2a to 52c4a of the insertion holes 52c2 to 52c4 of the circuit board 52, the inner circumference portions 54d2a to 54d4a of the insertion holes 54d2 to 54d4 of the light guide 54, and the inner circumference portions 51a2b1 to 51a2d1 of the insertion holes 51a2b to 51a2d of the emblem 51.

[0047] Next, the method for assembling the optical unit 50 onto the pad 5 will be described. The worker performing the assembly first places the emblem 51 on the floor or table and places the light guide 54 on the emblem 51. At this time, the worker fits the positioning projection 51b2 of the emblem 51 into the positioning groove 54c of the light guide 54. Next, the worker fits the positioning projection 51b2 of the emblem 51 into the positioning groove 52b of the circuit board 52 and places the circuit board 52, on which the LEDs 53a to 53e and control components 57 are mounted, onto the light guide 54.

[0048] Next, the worker places the mounting portion 55a of the holder member 55 onto the circuit board 52. At this time, the worker inserts the partition walls 55f1 to 55f4 of the holder member 55 into the insertion holes 52c1 to 52c4 of the circuit board 52, the insertion holes 54d1 to 54d4 of the light guide 54, and the insertion holes 51a2a to 51a2d of the emblem 51, thereby positioning the holder member 55 in relation to the emblem 51, the circuit board 52, and the light guide 54. This aligns the positions of the insertion holes 51a2a to 51a2d, 52c1 to 52c4, 54d1 to 54d4, and 55d1 to 55d4 of the holder member 55, allowing them to communicate with each other.

[0049] Next, the worker inserts the claw portion 51b1 of the emblem 51 into the engagement hole 55b of the holder member 55 and engages it. Specifically, the worker elastically deforms the claw portion 51b1 so that it extends in the front-rear direction, and inserts the claw portion 51b1 into the engagement hole 55b from the rear so that the claw portion 51b1 penetrates to the front of the engagement hole 55b. As a result, the portion of the claw portion 51b1 that protrudes forward from the engagement hole 55b returns to its original position and catches on the surrounding portion of the holder member 55 around the engagement hole 55b, preventing the claw portion 51b1 from coming loose. In this way, the claw portion 51b1 engages with the engagement hole 55b, and the optical unit 50 is unitized.

[0050] Next, the protrusions 5a2a to 5a2d of the pad 5 are inserted into the insertion holes 51a2a to 51a2d, 52c1 to 52c4, 54d1 to 54d4, and 55d1 to 55d4 of the emblem 51, circuit board 52, light guide 54, and holder member 55 of the optical unit 50. Then, the tips 5a2a2 to 5a2d2 of the protrusions 5a2a to 5a2d of the pad 5 and the connecting walls 55e2 to 55e4 of the holder member 55 are melted by heat or vibration, thereby welding the protrusions 5a2a to 5a2d to the connecting walls 55e2 to 55e4 of the holder member 55. In this way, the optical unit 50 is assembled to the pad 5.

[0051] As described above, the assembled optical unit 50 emits light from LEDs 53a to 53e in accordance with the control of the control component 57. The light emitted from LED 53a enters the incident surface 54a1 of the light guide 54 and is emitted from the exit surface 54b1. This light then passes through the projection 51a1a of the emblem 51 and is projected through the through-hole 5a1a of the pad 5 toward the outside of the pad 5, specifically toward the rear where the driver M is located. In this way, the lighting section 5x1 of the pad 5 lights up.

[0052] Furthermore, the light emitted from the LED 53b first enters the incident surface 54a2 of the light guide 54 and is emitted from the exit surface 54b2. After that, this light passes through the projection 51a1b of the emblem 51 and is irradiated to the outside of the pad 5 through the through hole 5a1b of the pad 5. In this way, the lighting section 5x2 of the pad 5 lights up.

[0053] Similarly, the light emitted from LEDs 53c to 53e enters the incident surfaces 54a3 to 54a5 of the light guide 54 and is emitted from the exit surfaces 54b3 to 54b5. After that, this light passes through the protrusions 51a1c to 51a1e of the emblem 51 and is irradiated to the outside of the pad 5 through the through holes 5a1c to 5a1e of the pad 5. In this way, the illuminated parts 5x3 to 5x5 of the pad 5 light up. As a result, the illuminated parts 5x1 to 5x5 of the pad 5 light up together to display the letters "SSSSS".

[0054] In this embodiment, the holder member 55 extends forward from the respective periphery of the insertion holes 55d1 to 55d4 so as to cover the side surfaces 5a2a1 to 5a2d1 of the protrusions 5a2a to 5a2d of the pad 5, and has connecting walls 55e1 to 55e4 to which the protrusions 5a2a to 5a2d are welded. With this configuration, the volume of the welded portion between the holder member 55 and the protrusions 5a2a to 5a2d of the pad 5 can be supplemented not only by the protrusions 5a2a to 5a2d but also by the connecting walls 55e1 to 55e4 of the holder member 55. Therefore, even if the protrusions 5a2a to 5a2d of the pad 5 are short and have a small outer diameter, the circuit board 52 can be firmly attached to the pad 5.

[0055] Furthermore, the holder member 55 extends rearward from the respective periphery of the insertion holes 55d1 to 55d4 so as to cover the side surfaces 5a2a1 to 5a2d1 of the protrusions 5a2a to 5a2d of the pad 5, and has partition walls 55f1 to 55f4 positioned between the inner periphery 52c1a to 52c4a of the insertion holes 52c1 to 52c4 of the circuit board 52 and the side surfaces 5a2a1 to 5a2d1 of the protrusions 5a2a to 5a2d of the pad 5. With this configuration, as described above, the partition walls 55f1 to 55f4 can suppress the leakage of molten material onto the mounting surface 52a of the circuit board 52 when the protrusions 5a2a to 5a2d of the pad 5 are welded to the connecting walls 55e1 to 55e4 of the holder member 55, thereby preventing deterioration of the optical characteristics of the LEDs 53a to 53e.

[0056] Furthermore, the sides of the partition walls 55f1 to 55f4 are in contact with the inner circumferential portions 52c1a to 52c4a of the insertion holes 52c1 to 52c4 of the circuit board 52, the inner circumferential portions 54d1a to 54d4a of the insertion holes 54d1 to 54d4 of the light guide 54, and the inner circumferential portions 51a2a1 to 51a2d1 of the insertion holes 51a2a to 51a2d of the emblem 51. This allows the emblem 51, light guide 54, circuit board 52, and holder member 55 to be easily positioned using the partition walls 55f1 to 55f4 when assembling them, thereby improving the ease of assembly of the optical unit 50.

[0057] Furthermore, both the pad 5 and the holder member 55 are made of synthetic resin. Therefore, their high affinity makes them easy to bond during welding, allowing for a stronger weld between the pad 5 and the holder member 55. If this point is not considered, the pad 5 and holder member 55 do not necessarily need to be made of the same material and could be made of other materials.

[0058] In this embodiment, when the protrusions 5a2a to 5a2d of the pad 5 are welded to the connecting walls 55e1 to 55e4 of the holder member 55, a configuration in which both are partially melted and the molten portions are completely mixed has been described. However, the present invention is not limited to this configuration. That is, as shown in Figure 11, a configuration in which only the protrusions 5a2a to 5a2d of the pad 5 are partially melted and welded to the connecting walls 55e1 to 55e4 of the holder member 55 so as to overlap them may be used. Even with such a configuration, the area of ​​the height of the connecting walls 55e1 to 55e4 is added to the contact area of ​​the welded portion of the protrusions 5a2a to 5a2d with the connecting walls 55e1 to 55e4. Therefore, the mounting strength of the circuit board 52 to the pad 5 can be increased compared to a configuration in which the holder member 55 does not have connecting walls 55e1 to 55e4. [Explanation of symbols]

[0059] 2...Boss part, 5...Pad, 5a2a~5a2d...Protruding part, 5a2a1~5a2d1...Side, 5x1~5x5...Lighting part, 10...Steering wheel (steering device), 30...Vehicle, 35...Steering shaft (steering axis), 52...Circuit board (board), 52c1~52c4...Through hole (board insertion hole), 52c1a~52c4a...Inner circumference, 53a~53e...LED (light source), 55...Holder member (holding member), 55d1~55d4...Through hole, 55e1~55e4...Connecting wall, 55f1~55f4...Bulkhead

Claims

1. A steering system mounted on a vehicle, A boss portion connected to the steering shaft of the aforementioned vehicle, A pad that covers the boss portion from the rear, having a light-up portion that illuminates and a protruding portion that extends forward from the front surface of the pad, A circuit board on which a light source that emits light to illuminate the aforementioned lighting unit is mounted, A retaining member positioned in front of the pad and holding the substrate, having an insertion hole through which the protrusion is inserted, and a connecting wall extending forward from the periphery of the insertion hole so as to cover the side surface of the protrusion, to which the protrusion is welded, A steering device characterized by being equipped with

2. The substrate has a substrate insertion hole through which the protruding portion is inserted, The steering device according to claim 1, characterized in that the retaining member extends rearward from the periphery of the insertion hole so as to cover the side surface of the protruding portion and has a partition wall disposed between the inner periphery of the substrate insertion hole and the side surface of the protruding portion.

3. The steering device according to claim 2, characterized in that the partition wall and the inner circumference of the substrate insertion hole are in contact.

4. The steering device according to claim 1, characterized in that the pad and the retaining member are made of synthetic resin.

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