Cover member and illumination device

Abstract

To realize at least one of a light guide function and a light diffusion function while suppressing an increase in a manufacturing cost in an illumination device mounted on a steering handle.SOLUTION: A cover member that is used in an illumination device mounted on a steering handle and has light transmissivity for visible light, includes: a plate-like body part which forms a portion of the outer surface of the steering handle and emits visible light output by a light-emitting element in the illumination device to the outside of the steering handle; and an optical function part which is integrated with the body part, is provided on at least one of the inner side surface of the body part being the steering handle side and the outer side surface of the body part being the external side in the mounted state where the illumination device is mounted on the steering handle, and realizes at least one of a light guide function to guide the visible light emitted by the light-emitting element, and a light diffusion function to diffuse the visible light.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present disclosure relates to a cover member and an illumination device.

Background Art

[0002] In a steering wheel, it has been proposed to attach and use a device that emits visible light (hereinafter referred to as an "illumination device") at a position visible to the driver. Specifically, for example, as in Patent Document 1, there is proposed an illumination device including a substrate provided with a visible light source, a cover member that extends along the rim and constitutes an outer wall from which light is emitted, and a light guide member that guides visible light emitted from the light source to the cover member. In the illumination device of Patent Document 1, the light guide member has a function of diffusing visible light (hereinafter referred to as a "light diffusion function") in addition to a function of guiding visible light (hereinafter referred to as a "light guiding function"). Specifically, a diffusion layer for diffusing visible light is formed on the surface of the light guide member where visible light is output to the cover member, so as to diffuse visible light over the entire display area of the cover portion.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in an illumination device such as Patent Document 1, since it is necessary to prepare and assemble a light guide member as an independent member, there is a problem that the manufacturing cost increases. Such a problem is common in a configuration where the light guide member has only a light guiding function and does not have a light diffusion function, or conversely, in a configuration where the light guide member has only a light diffusion function and does not have a light guiding function. For this reason, in an illumination device mounted on a steering wheel, a technique capable of realizing at least one of a light guiding function and a light diffusion function while suppressing an increase in manufacturing cost is desired.

Means for Solving the Problems

[0005] The present disclosure has been made to solve at least a part of the above-described problems and can be realized in the following forms.

[0006] (1) According to one aspect of the present disclosure, there is provided a cover member used for an illumination device mounted on a steering wheel and having visible light transmissivity. This cover member forms a part of the outer surface of the steering wheel, and includes a plate-shaped main body portion that emits the visible light output from a light emitting element included in the illumination device to the outside of the steering wheel, and an optical function portion integrated with the main body portion. The optical function portion is provided on at least one of the inner surface of the main body portion on the steering wheel side and the outer surface of the main body portion on the outside in a mounted state where the illumination device is mounted on the steering wheel, and realizes at least one of a light guiding function of guiding the visible light output from the light emitting element and a light diffusion function of diffusing the visible light. According to the cover member of this aspect, since the optical function portion that realizes at least one of the light guiding function and the light diffusion function is integrated with the main body portion of the cover member, when used in the manufacture of the illumination device, compared with a configuration in which the optical function portion is formed as a separate member from the main body portion, it is possible to realize at least one of the light guiding function and the light diffusion function while suppressing an increase in manufacturing cost. (2) In the cover member of the above-described embodiment, the optical function portion includes a protruding portion that protrudes from the inner surface and has visible light transmissibility, and a tip portion of the protruding portion faces the light-emitting element, and the protruding portion may have the light guiding function. According to the cover member of this embodiment, the optical function portion includes a protruding portion that protrudes from the inner surface of the main body portion and has visible light transmissibility, the tip portion of the protruding portion faces the light-emitting element, and the protruding portion has the light guiding function. Therefore, the protruding portion having the light guiding function can be arranged in the vicinity of the light-emitting element, and it is possible to suppress the waste that the visible light output from the light-emitting element becomes wasted without going toward the cover member. (3) In the cover member of the above-described embodiment, the optical function portion includes a protruding portion that protrudes from the inner surface and has visible light transmissibility, the protruding portion is arranged at a position where the visible light output from the light-emitting element is incident, and the protruding portion has a reflecting surface at an end portion on the side opposite to the inner surface for reflecting the incident visible light and directing it toward the main body portion, and the protruding portion may have the light guiding function. According to the cover member of this embodiment, the protruding portion is arranged at a position where the visible light output from the light-emitting element is incident, the protruding portion has a reflecting surface at an end portion on the side opposite to the inner surface for reflecting the incident visible light and directing it toward the main body portion, and the protruding portion has the light guiding function. Therefore, even in a configuration where the tip portion of the protruding portion does not face the light-emitting element, it is possible to direct the visible light output from the light-emitting element toward the main body portion by using the reflecting surface. (4) In the cover member of the above-described embodiment, the protruding portion is arranged at a position displaced in the radial direction of the grip portion of the steering wheel in a state where the cover member is attached to the steering wheel with respect to the light-emitting element, and the visible light output from the light-emitting element may be incident on the protruding portion along the radial direction. According to the cover member of this embodiment, even in a state where the protruding portion is displaced along the radial direction of the grip portion with respect to the light-emitting element, it is possible to direct the visible light output from the light-emitting element toward the main body portion by using the protruding portion. (5) In the cover member of the above-described embodiment, the protruding portion is disposed at a position shifted in the circumferential direction of the gripping portion of the steering wheel in a state where the cover member is attached to the steering wheel with respect to the light-emitting element, and the visible light output from the light-emitting element may be incident on the protruding portion along the circumferential direction. According to the cover member of this embodiment, even in a state where the protruding portion is disposed so as to be shifted along the circumferential direction of the gripping portion with respect to the light-emitting element, the visible light output from the light-emitting element can be directed toward the main body portion by using the protruding portion. (6) In the cover member of the above-described embodiment, the optical function portion may include an opposing surface that faces the light-emitting element and is formed in a concave shape toward the light-emitting element and has the light diffusion function. According to the cover member of this embodiment, since the optical function portion includes an opposing surface that faces the light-emitting portion of the light-emitting element, is formed in a concave shape toward the light-emitting element, and has the light diffusion function, the visible light can be diffused over a wider range compared to a configuration using an optical function portion including an opposing surface formed in a convex shape toward the light-emitting element. (7) In the cover member of the above-described embodiment, the optical function portion may include an opposing surface that faces the light-emitting element and has a plurality of irregularities formed thereon and has the light diffusion function. According to the cover member of this embodiment, since the optical function portion is an opposing surface that faces the light-emitting element, has a plurality of irregularities formed thereon, and has the light diffusion function, the visible light output from the light-emitting element can be diffused by using the plurality of irregularities. (8) In the cover member of the above-described embodiment, the optical function portion may be a film portion formed on the outer surface of the main body portion, have a predetermined pattern, and include the film portion having the light diffusion function. According to the cover member of this embodiment, since the optical function portion is a film portion formed on the outer surface of the main body portion, has a predetermined pattern, and includes the film portion having the light diffusion function, the visible light output from the light-emitting element can be diffused by using the predetermined pattern. (9) As another embodiment of the present disclosure, an illumination device is provided. This illumination device includes the cover member of the above-described embodiment, a substrate including the light-emitting element, and a base member to which the cover member and the substrate are attached and which holds the cover member and the substrate, the base member having a support portion disposed so as to surround the protruding portion. According to the illumination device of this embodiment, since it includes the cover portion of the above-described embodiment, at least one of the light guiding function and the light diffusing function can be realized while suppressing an increase in the manufacturing cost of the illumination device.

Brief Description of the Drawings

[0007]

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Figure 11

Best Mode for Carrying Out the Invention

[0008] A. First Embodiment: A1. Overall Configuration of Steering Wheel 100: FIG. 1 is a plan view showing the external shape of a steering wheel 100 in a state where an illumination device 200 as an embodiment of the present disclosure is attached (hereinafter, also referred to as a “mounted state”). The steering wheel 100 is disposed and used in the driver's seat of a vehicle. Examples of the vehicle include a vehicle equipped with an engine, a hybrid vehicle (HEV), a plug-in hybrid vehicle (PHEV), a battery electric vehicle (BEV), and a fuel cell vehicle (FCV). The steering wheel 100 is a part of a steering device operated by a driver of the vehicle. In FIG. 1, the steering wheel 100 in a state (hereinafter, also referred to as a “reference state”) where it is connected to a steering shaft SH in the vehicle and the vehicle is traveling straight is shown. Further, in FIG. 1, the external configuration of the side of the steering wheel 100 facing the driver (the “rear” side described later) is shown. The steering wheel 100 is configured to be rotatable about the axis AX of the steering shaft SH. The rotation of the steering wheel 100 is transmitted to a steering gear box (not shown) via the steering shaft SH.

[0009] In the present embodiment, the direction along the axis AX of the steering shaft SH is associated with the traveling direction of the vehicle and is referred to as the “front-rear direction” (front direction and rear direction). Further, among the directions orthogonal to the axis AX, the direction overlapping with the vertical direction (vertically upward and vertically downward) as viewed from the driver is referred to as the “vertical direction”. Further, among the directions orthogonal to the axis AX, the direction parallel to the left-right direction (width direction) of the vehicle is referred to as the “left-right direction”.

[0010] The steering wheel 100 includes a ring-shaped grip portion 110, a boss portion 130 disposed at a substantially central portion of the grip portion 110, three spoke portions 120, and an illumination device 200 disposed at a part of the grip portion 110.

[0011] The gripping portion 110 is gripped by the driver when operating the steering wheel 100. In the present embodiment, the shape of the gripping portion 110 is substantially an annular shape. The central axis of the gripping portion 110 coincides with the axis AX of the steering shaft SH. Note that the shape of the gripping portion 110 may be an arbitrary shape such as a polygonal shape or an elliptical shape instead of the substantially annular shape, or may be an asymmetric shape such as a so-called D shape. Further, the shape of the gripping portion 110 is not limited to an annular shape, and may be an arbitrary shape formed by a plurality of parts provided at positions separated from each other. As will be described later, the gripping portion 110 is configured by stacking a plurality of members in the thickness direction. The outermost layer is formed by an outer skin layer (outer skin layer 80 described later) formed of a leather member. Although not shown in FIG. 1, a recess (recess C1 described later) for accommodating a part of the illumination device 200 is formed in a part of the upper side of the gripping portion 110 in the reference state. A part of the illumination device 200 is accommodated in the recess C1. In other words, the illumination device 200 is fitted into the recess C1. And the opening of the recess C1 is blocked by the illumination device 200. As shown in FIG. 1, a display portion 19 is provided on the rear surface side of the illumination device 200 (the outer surface of the main body portion 11 of the cover member 10 described later). Visible light is irradiated from the display portion 19 and emits light with a predetermined luminance. Note that the display portion 19 is painted with a smoke paint. On the other hand, the region of the cover member 10 described later excluding the display portion 19 is painted with a black paint. Therefore, light emission in such a portion is suppressed.

[0012] The three spoke portions 120 connect the grip portion 110 and the boss portion 130. The boss portion 130 corresponds to the connection site when connecting the steering wheel 100 to the steering shaft SH. Inside the boss portion 130, folded airbags and inflators (not shown in any figure) are accommodated. Additionally, inside the boss portion 130, a temperature adjustment circuit constituting a heater device and various sensor devices for detecting the room temperature and the grip of the grip portion 110 by the user may be further accommodated. Various operation buttons for operating a navigation device, an audio device, etc. mounted on the vehicle may be provided on the three spoke portions 120 and the boss portion 130.

[0013] The illumination device 200 emits visible light. By emitting visible light from the illumination device 200, various information can be notified to the driver. For example, by emitting lights of various colors or blinking lights, some information can be notified to the driver. Specifically, by emitting red light, the driver can be prompted to grip the steering wheel.

[0014] FIG. 2 is a plan view showing the external shape of the steering wheel 100 in a state where the cover member 10 and the base member 40 are removed from the mounted state. As will be described later, in the illumination device 200, a cover member 10 having light transmissibility is disposed at a position facing the driver, and a base member 40 (to be described later) is disposed on the front side of the cover member 10. FIG. 2 schematically shows the steering wheel 100 in a state where the cover member 10 and the base member 40 are removed.

[0015] As shown in Fig. 2, when the cover member 10 and the base member 40 are removed, the light-emitting unit 30, which is one of the elements constituting the illumination device 200, is exposed. The light-emitting unit 30 includes a substrate 31 and a plurality of light-emitting elements provided on the surface of the substrate 31. In this embodiment, the "plurality of light-emitting elements" includes a plurality of LEDs 32. The substrate 31 has an arc-shaped and strip-like external shape that is curved along the circumferential direction (hereinafter, also simply referred to as the "circumferential direction") of the grip portion 110 as viewed from the driver. Hereinafter, the radial direction (the direction orthogonal to the axis AX) of the grip portion 110 is also simply referred to as the "radial direction". The plurality of LEDs 32 are arranged at positions close to the lower end portion on the rearward side surface of the substrate 31 and are separated from each other by a predetermined distance along the circumferential direction. The LED 32 emits visible light. In this embodiment, as the LED 32, a visible light LED capable of emitting red light, green light, and blue light is used. Each LED 32 emits visible light to the side opposite to the substrate 31. That is, visible light is emitted from the front side to the rear side.

[0016] A2. Detailed configuration of the illumination device 200: Fig. 3 is a first exploded perspective view showing the detailed configuration of the illumination device 200. Fig. 4 is a second exploded perspective view showing the detailed configuration of the illumination device 200. Fig. 5 is a first cross-sectional view showing the cross-section of the steering handle 100. Fig. 6 is a second cross-sectional view showing the cross-section of the steering handle 100. Fig. 3 corresponds to an exploded perspective view of the illumination device 200 as viewed approximately from the rear side toward the front side. Fig. 4 corresponds to an exploded perspective view of the illumination device 200 as viewed approximately from the front side toward the rear side. Fig. 5 shows the V-V cross-section shown in Fig. 2. Fig. 6 shows the VI-VI cross-section shown in Fig. 2.

[0017] As shown in Figs. 3 and 4, in addition to the above-described light-emitting unit 30, the illumination device 200 includes a cover member 10 and a base member 40. The illumination device 200 has a structure in which the light-emitting unit 30 and the cover member 10 are assembled and integrated in the front-rear direction with the base member 40 interposed therebetween.

[0018] As shown in FIGS. 3 and 4, the cover member 10 includes a main body portion 11, a surrounding portion 12, a plurality of engaging walls 15, and a protruding portion 16. In the present embodiment, the cover member 10 is formed of polycarbonate (PC) resin. Note that it may be formed of acrylic resin instead of PC resin. The main body portion 11 has a plate-like outer appearance shape and forms the outer surface of the steering wheel 100 continuously with the outer skin layer 80 as shown in FIGS. 5 and 6. The main body portion 11 emits the visible light output from the LED 32 to the outside of the steering wheel 100 from the display portion 19 shown in FIG. 1. Similar to the substrate 31 described above, the main body portion 11 has an arc-shaped and belt-like outer appearance shape that is curved along the circumferential direction as viewed from the driver. The main body portion 11 includes a display portion 19 (see FIG. 1) having visible light transmissivity. In the present embodiment, the display portion 19 has a transmittance of approximately 25% with respect to visible light. Note that the transmittance of visible light may be any value higher than 0%. In addition to the function of protecting the light emitting portion 30, the main body portion 11 has a function of restricting the region through which the visible light emitted from the LED 32 passes (in other words, a function of masking the region where it is not desired to emit light).

[0019] As shown in FIG. 4, the surrounding portion 12 is provided on the front-side surface (inner surface) of the main body portion 11. In a state where the illumination device 200 is assembled (hereinafter, also simply referred to as the “assembled state”), the surrounding portion 12 surrounds, over the entire circumference, a support portion 41 that protrudes rearward from a recess C1 of a base member 40 shown in FIGS. 3, 5, and 6, and a protruding portion 16 corresponding to a part of a cover member 10 housed in the support portion 41. The recess C1 opens to the front-side surface of the base member 40 and has a groove-like structure extending along the circumferential direction. Among the surrounding portion 12, a side wall portion 13 corresponding to a side wall along the radial direction protrudes from the front-side surface of the main body portion 11, that is, from the inner surface in the depth direction of the recess C1. In the present embodiment, the “depth direction of the recess C1” substantially coincides with the front-rear direction as is apparent from FIGS. 3, 5, and 6. As shown in FIGS. 3 and 4, a plurality of engagement holes 14 are formed in the side wall portion 13. In the assembled state, an engagement claw 44 (see FIG. 3) provided on the outer peripheral surface of the support portion 41 of the base member 40 engages with the engagement holes 14. Such engagement is realized as a so-called snap fit.

[0020] As shown in FIG. 4, the plurality of engagement walls 15 have a thin-wall-like outer appearance protruding forward and are provided with engagement holes. In the assembled state, the engagement walls 15 are arranged in contact with an engagement wall 45 (see FIG. 3) of the base member 40. Then, in the assembled state, an engagement claw provided on the engagement wall 45 engages with the engagement holes of the engagement walls 15. Such engagement is also realized as a so-called snap fit.

[0021] As shown in FIGS. 4 to 6, the protruding portion 16 has a structure that protrudes forward from the inner surface of the main body portion 11. Further, as shown in FIG. 4, the protruding portion 16 has an arc-shaped outer appearance that curves along the circumferential direction as viewed from the driver. The "inner surface of the main body portion 11" is the surface of the main body portion 11 that faces forward, that is, the inner side of the illumination device 200 in the assembled state. By providing the protruding portion 16 with such a configuration, as shown in FIGS. 5 and 6, in a cross section including the axis AX, the cover member 10 has a substantially T-shaped cross-sectional shape. The protruding portion 16 has visible light transmissibility and guides incident visible light in a predetermined direction while reflecting it at the interface with the outside. That is, in the present embodiment, the protruding portion 16 realizes a function of guiding visible light (hereinafter referred to as "light guiding function"). The surface S1 of the tip of the protruding portion 16, that is, the front end surface, faces the LED 32. Visible light output from the LED 32 is incident on the surface S1. The surface S1 corresponds to the "opposing surface" of the present disclosure. Since the protruding portion 16 protrudes forward from the main body portion 11, the protruding portion 16 can be disposed in the vicinity of the LED 32. Therefore, it is possible to suppress the waste of visible light output from the LED 32 from being wasted without going toward the cover member 10.

[0022] As shown in FIG. 5, a film portion f1 is formed on the outer surface S2 of the main body portion 11. In the lower left of FIG. 5, a partial region Ar0 including the film portion f1 and the outer surface S2 is schematically shown enlarged. The film portion f1 is composed of three layers formed on the outer surface of the main member 111 that mainly forms the main body portion 11. Specifically, the film portion f1 includes a paint layer f13, a film base material f12, and a hard coat layer f11 in order from the side closer to the main member 111. The paint layer f13 is a layer composed of a smoke paint and a black paint. Specifically, as described above, in the display portion 19, the paint layer f13 is composed of a smoke paint, and in the other portions excluding the display portion 19, the paint layer f13 is composed of a black paint. Due to this paint layer f13, visible light is selectively emitted only from the display portion 19 on the outer surface S2. The film base material f12 serves as the main member of the film portion f1 and is the application target of the hard coat layer f11 and the paint layer f13. The film base material f12 is formed of, for example, a resin. The hard coat layer f11 is formed for the purpose of improving scratch resistance. The hard coat layer f11 is formed, for example, by screen printing a resin-based, silicon-based, or inorganic-based coating agent.

[0023] The base member 40 holds the light-emitting portion 30 attached to the front side of itself and also holds the cover member 10 attached to the rear side of itself. As shown in FIGS. 3 and 4, the base member 40 has an arc-shaped and strip-like appearance shape that curves along the circumferential direction when viewed from the driver. In the present embodiment, the base member 40 is configured as a single component formed of PC resin, similar to the cover member 10. Note that, instead of PC resin or in addition to PC resin, it may be configured as a single component formed of ABS resin. Further, it may be configured as a composite component in which a plurality of components are combined. As described above, a recess C1 that is continuous in the circumferential direction is formed on the rearward-facing surface of the base member 40. As shown in FIGS. 3 to 6, on the rearward-facing surface of the base member 40, covering portions 42 that are continuous in the circumferential direction are provided above and below the recess C1 with the recess C1 interposed therebetween. As shown in FIGS. 5 and 6, the cross-sectional shape of the outer surface of the covering portion 42 has a shape in which the angle between the surface existing upward and the surface existing downward with the top portion 43 interposed therebetween is an acute angle. The covering portion 42 is covered by an outer skin layer 80 described later.

[0024] In the recess C1, a through-hole penetrating in the thickness direction is formed in a portion corresponding to the protruding portion 16. As shown in FIGS. 5 and 6, the protruding portion 16 is inserted into such a through-hole. As shown in FIGS. 3, 5, and 6, in the recess C1, the support portion 41 described above is provided so as to surround the through-hole into which the protruding portion 16 is inserted. The support portion 41 is formed to protrude forward so as to surround the through-hole and the side surface of the protruding portion 16 inserted into the through-hole over the entire circumference, similar to the surrounding portion 12 of the cover member 10 shown in FIG. 4. As shown in FIG. 3, the support portion 41 has an arc-shaped and flattened cylindrical appearance shape. As described above, a plurality of engaging claws 44 are provided on the outer peripheral surface of the support portion 41, and such engaging claws 44 engage with the engaging holes 14 of the cover member 10 in the assembled state. The support portion 41 suppresses displacement of the protruding portion 16 in the vertical direction and the horizontal direction.

[0025] A3. Detailed configuration of the gripping portion 110: In the holding part 110, the cross-sectional configuration of the part other than the part where the illumination device 200 is mounted is different from the cross-sectional configuration of the part where the illumination device 200 is mounted shown in FIGS. 5 and 6 in that the illumination device 200 is not mounted, and the other configurations are the same. In FIG. 6, the detailed configuration of the film part f1 is omitted.

[0026] As shown in FIGS. 5 and 6, the holding part 110 includes a core metal 50, a core part 60, an element layer 70, the above-described illumination device 200, and an outer skin layer 80.

[0027] The core metal 50 is made of metal and is a member that forms the skeleton of the gripping portion 110. In the present embodiment, the core metal 50 is made of an aluminum alloy. Note that instead of the aluminum alloy, the core metal 50 may be formed of any type of metal such as a magnesium alloy or steel. The core portion 60 is disposed so as to cover the entire core metal 50 and forms the core of the gripping portion 110. The core portion 60 is formed of a soft synthetic resin having cushioning properties. Specifically, in the present embodiment, the core portion 60 is formed of a soft foaming material such as foamed polyurethane. The element layer 70 partially covers the core portion 60. The element layer 70 is a layer provided with a heating wire constituting the heater device and electrodes for detecting gripping. For example, it is formed of a conductive cloth obtained by subjecting a fiber fabric to a surface treatment such as carbon coating or metal plating. As shown in FIGS. 5 and 6, in the portion of the gripping portion 110 where the illumination device 200 is mounted, the element layer 70 also covers a part of the base member 40. The outer surface of the element layer 70 and a part of the outer surface of the base member 40 form a continuous curved surface. The outer skin layer 80 continuously covers the outer surface of the element layer 70, the outer surface of the covered portion 42 of the base member 40, and the inside of the concave portion C1 of the base member 40. As shown in FIGS. 5 and 6, the terminal portion of the leather member constituting the outer skin layer 80 is housed in the concave portion C1. The outer skin layer 80 is formed of a leather member. In the present embodiment, the leather member is constituted by natural leather such as top leather or split leather obtained by splitting top leather. Note that the leather member may be constituted by any type of leather material such as synthetic leather or artificial leather instead of natural leather.

[0028] A4. Manufacturing method of the steering handle 100: A method for manufacturing the steering handle 100 having the above-described configuration will be described. First, a member obtained by removing the cover member 10 from the illumination device 200 (hereinafter referred to as "illumination sub-assembly") is manufactured. Specifically, first, the cover member 10, the light-emitting portion 30, and the base member 40 are manufactured. In the manufacture of the cover member 10, first, the film portion f1 is formed. Specifically, the hard coat layer f11 is formed on one surface of the film base material f12 by screen printing, and the paint layer f13 is formed on the other surface by screen printing, whereby the film portion f1 is formed. Thereafter, the obtained film portion f1 and the main member 111 are insert-molded to complete the cover member 10. Thereafter, the light-emitting portion 30 is attached to the back surface (front side in the assembled state) of the base member 40. At this time, the three screws 90 shown in FIGS. 3 and 4 are accommodated in the notch portion 35 provided at the upper edge portion of the substrate 31 and screwed into the screw holes 46 (see FIG. 6) provided in the base member 40. In this way, the illumination sub-assembly is completed. Next, the core metal 50 is formed. The core portion 60 and the element layer 70 are formed so as to surround the core metal 50. Hereinafter, the member thus obtained is referred to as a "handle material". The formation of the handle material may be realized, for example, by two-color molding. Subsequently, the illumination sub-assembly is fastened to the core metal 50 using screws. Thereby, the handle material and the illumination sub-assembly are integrated. Note that FIGS. 5 and 6 show cross-sections at portions without fastening screws. In this way, by fastening the illumination sub-assembly and the core metal 50 to each other with screws, the heat generated with the light emission of the light-emitting portion 30 can be transmitted to the core metal 50, and the illumination device 200 can be prevented from overheating. Subsequently, a leather member is wound around the outer surface of the member in which the handle material and the illumination sub-assembly are integrated to form the outer skin layer 80. The outer skin layer 80 may be formed, for example, by winding parts of a plurality of leather members in the circumferential direction. Subsequently, an adhesive is applied to the wall surface of the recess C1, the terminal portion of the outer skin layer 80 is bent along the shape of the covering portion 42 and accommodated in the recess C1, and such a terminal portion is adhered to the wall surface of the recess C1.Subsequently, the cover member 10 is fitted into the concave portion C1, and the cover member 10 is attached to the base member 40 by snap fit. In addition to the above procedures, there are procedures such as accommodating an airbag or an inflator (not shown) in the boss portion 130, but the description of these procedures will be omitted.

[0029] According to the cover member of the first embodiment described above, in the cover member 10, the protruding portion 16 as the optical functional portion that realizes the light guiding function is integrated with the main body portion 11 of the cover member 10. Therefore, when used in the manufacture of the illumination device 200, compared with the configuration in which the optical functional portion is formed as a separate member from the main body portion 11, the light guiding function can be realized while suppressing an increase in manufacturing cost.

[0030] Further, the cover member 10 includes a protruding portion 16 that protrudes from the inner surface of the main body portion 11 and has visible light transmissivity. The tip of the protruding portion 16 faces the LED 32, and the protruding portion 16 has a light guiding function. Therefore, the protruding portion 16 having the light guiding function can be arranged in the vicinity of the LED 32, and it is possible to prevent the visible light output from the LED 32 from being wasted without going toward the cover member 10.

[0031] B. Second Embodiment: FIG. 7 is a perspective view showing a detailed configuration of the cover member 10a of the second embodiment. FIG. 7 corresponds to an exploded perspective view of the cover member 10a as seen from approximately the front side toward the rear side. In the lower right of FIG. 7, the region Ar1 in the cover member 10a is shown enlarged. The region Ar1 is a partial region on the front side of the cover member 10a where the surrounding portion 12 and the protruding portion 16a of the second embodiment are formed.

[0032] The cover member 10a of the second embodiment differs from the cover member 10 of the first embodiment in that it includes a protruding portion 16a instead of the protruding portion 16. Since other configurations of the cover member 10a are the same as those of the cover member 10, the same reference numerals are assigned to the same components, and detailed descriptions thereof are omitted. Further, the illumination device 200 of the second embodiment differs from the illumination device 200 of the first embodiment only in that it includes a cover member 10a instead of the cover member 10.

[0033] As shown in FIG. 7, in the protruding portion 16a of the second embodiment, a plurality of uneven portions 17 are formed on the surface S1 at predetermined intervals along the circumferential direction. As shown in the enlarged view of FIG. 7, the uneven portion 17 includes a plurality of unevennesses. More specifically, the uneven portion 17 has a configuration in which a plurality of grooves extending in the short side direction of the surface S1 are arranged. Such grooves may be realized by previously forming such a shape in a mold when the protruding portion 16a is injection-molded. Each uneven portion 17 is arranged at a position corresponding in the front-rear direction with respect to each LED 32. Therefore, the visible light output from each LED 32 is incident on each uneven portion 17. The incident visible light is diffused by the uneven shape in the uneven portion 17 and directed toward the main body portion 11. In this way, the uneven portion 17 realizes a function of diffusing the visible light output by the LED 32 (hereinafter referred to as the "light diffusion function"). Therefore, in the second embodiment, it can be said that the protruding portion 16a is an optical functional portion that realizes both a light guiding function and a light diffusion function.

[0034] The luminance on the surface of the cover member was measured for the illumination device 200 using the cover member 10a including the protruding portion 16a of the second embodiment having such a configuration and the illumination device using the cover member of the comparative example without the protruding portion. As a result, the average luminance of the cover member 10a of the second embodiment was 4.6 times that of the cover member of the comparative example. Further, when the ratio of the maximum luminance value to the minimum luminance value (maximum luminance value / minimum luminance value) in each cover member was compared between these two cover members, the ratio in the cover member 10a of the second embodiment was 0.8 times that of the cover member of the comparative example. From these facts, it was found that by using the cover member 10a of the second embodiment, more light can be diffused and luminance unevenness can be reduced.

[0035] The cover member 10a of the second embodiment described above has the same effects as the cover member 10 of the first embodiment. In addition, the protruding portion 16a, which is an optical functional portion, includes a surface S1 that is an opposing surface facing the LED 32 and has a plurality of unevennesses formed thereon and has a light diffusion function. Therefore, the visible light output from the LED 32 can be diffused using the plurality of unevennesses.

[0036] C. Third Embodiment: FIG. 8 is a perspective view showing a detailed configuration of the cover member 10b of the third embodiment. FIG. 8 corresponds to an exploded perspective view of the cover member 10b viewed approximately from the front side toward the rear side. In the lower right of FIG. 8, a region Ar2 in the cover member 10b is shown enlarged. The region Ar2 is a partial region on the front side of the cover member 10b where the surrounding portion 12 and the protruding portion 16b of the third embodiment are formed.

[0037] The cover member 10b of the third embodiment differs from the cover member 10 of the first embodiment in that it includes a protruding portion 16b instead of the protruding portion 16. Since the other configurations of the cover member 10b are the same as those of the cover member 10, the same reference numerals are assigned to the same components, and detailed descriptions thereof are omitted. Further, the illumination device 200 of the third embodiment differs from the illumination device 200 of the first embodiment only in that it includes a cover member 10b instead of the cover member 10.

[0038] As shown in FIG. 8, in the protruding portion 16b of the third embodiment, a plurality of recesses 18 are formed at predetermined intervals along the circumferential direction on the surface S1. As shown in the enlarged view of FIG. 7, the recess 18 has an appearance shape in the form of a notch of approximately a semi-circle when viewed in the vertical direction. Such a structure may be realized by forming such a shape in advance in the mold when injection molding the protruding portion 16b. Each recess 18 is arranged at a corresponding position in the front-rear direction with respect to each LED 32. Therefore, the visible light output from each LED 32 is incident on each recess 18. The incident visible light is diffused by the concave shape in the recess 18 and heads toward the main body portion 11. Here, the visible light incident on the concave shape is diffused over a wider range than the visible light incident on the convex shape. Therefore, according to the cover member 10b of the present embodiment, visible light can be diffused over a wider range, and the number of LEDs 32 can be reduced.

[0039] The cover member 10b of the third embodiment described above has the same effects as the cover member 10 of the first embodiment. In addition, the protruding portion 16b, which is an optical functional portion, includes a surface S1 that is a facing surface facing the LED 32 and is formed in a concave shape toward the LED 32 and has a light diffusion function. Therefore, visible light can be diffused over a wider range compared to a configuration using an optical functional portion including a facing surface formed in a convex shape toward the LED 32. Generally, visible light incident on a concave structure is refracted in such a way that visible light is emitted over a wider range compared to visible light incident on a convex structure formed of the same type of material.

[0040] D. Fourth Embodiment: FIG. 9 is a cross-sectional view showing a cross-section of the steering wheel 100c of the fourth embodiment. In FIG. 9, similar to FIG. 5, a cross-section at the same position as the V-V cross-section shown in FIG. 2 is shown. The steering wheel 100c of the fourth embodiment is different from the steering wheel 100 of the first embodiment in that a cover member 10c is used instead of the cover member 10. Other configurations of the steering wheel 100c of the fourth embodiment are the same as those of the steering wheel 100 of the first embodiment, so the same reference numerals are given to the same configurations and detailed descriptions thereof are omitted. The cover member 10c of the fourth embodiment is different from the cover member 10 of the first embodiment in that it does not include the protruding portion 16 and includes a main body portion 11c instead of the main body portion 11.

[0041] The main body portion 11c is different from the main body portion 11 of the first embodiment in that it includes a film portion f1c instead of the film portion f1. In the lower left of FIG. 9, a partial region Ar3 including the film portion f1c is schematically shown enlarged. The film portion f1c is different from the film portion f1 of the first embodiment only in that it includes a light diffusion paint layer f14 further inside the paint layer f13. The light diffusion paint layer f14 is a layer in which paint is screen-printed in a predetermined pattern (hereinafter referred to as a "diffusion pattern") for diffusing visible light. Therefore, the film portion f1c has a light diffusion function.

[0042] The film portion f1c is formed by screen-printing a hard coat layer f11 and a paint layer f13 on a film base material f12 and then screen-printing a light diffusion paint in a predetermined pattern on the paint layer f13. By providing the light diffusion paint layer f14 in this way, the light irradiated from the LED 32 and incident on the main body portion 11c is diffused and emitted by the diffusion pattern of the light diffusion paint layer f14. For this reason, the visible light, which is so-called point light source output from each LED 32, is visually recognized by the driver as visible light with spread. In the fourth embodiment, the film portion f1c corresponds to the optical function portion of the present disclosure.

[0043] The cover member 10c of the fourth embodiment described above has the same effects as the cover member 10 of the first embodiment. In addition, the cover member 10c is a film portion f1c formed on the outer surface of the main body portion 11 (main member 111), has a predetermined pattern, and includes the film portion f1c having a light diffusion function. Therefore, the visible light output from the LED 32 can be diffused using the predetermined pattern.

[0044] E. Other Embodiments: (E1) In each embodiment, the substrate 31 was attached to the base member 40 by screwing, but the present disclosure is not limited to this. For example, the base member 40 may be provided with engaging claws, and the substrate 31 may be attached by engaging with such engaging claws.

[0045] (E2) In each embodiment, the illumination device 200 was provided in the gripping portion 110, but the present disclosure is not limited to this. For example, the illumination device 200 may be provided at any part of the steering handles 100, 100c, such as the boss portion 130 or the spoke portion 120. In this case, the shape and configuration of the illumination device 200 can be appropriately changed according to the size and shape of the place where the illumination device 200 is provided. Note that the position of the illumination device 200 is preferably a position directly visible to the driver. However, for example, when the light emitted from the illumination device 200 is reflected on the surface of any part inside the vehicle, for example, the surface of the instrument panel, and such reflected light is visible to the driver, the position of the illumination device 200 may be a position not directly visible to the driver.

[0046] (E3) In the first to third embodiments, the LED 32 emitted visible light from the front side to the rear side, i.e., on the side opposite to the substrate 31, but the present disclosure is not limited to this. For example, as shown in FIG. 10, the arrangement position of the LED 32 on the substrate 31 is located downward (radially inward) compared to each embodiment, and the LED 32 may be configured to emit visible light from the lower side to the upper side (from the radially inner side to the radially outer side). In such a configuration, the cover member 10d may include a protruding portion 16d instead of the protruding portion 16. The protruding portion 16d includes a reflecting surface RS having an inclination of approximately 45° at the tip (frontward end). The visible light output from the LED 32 and incident on the protruding portion 16d is reflected rearward at the reflecting surface RS. Note that the inclination angle of the reflecting surface RS is not limited to 45°, and may be any angle within the range of 30° to 60°. In such a configuration, the protruding portion 16d is arranged at a position shifted in the radial direction with respect to the LED 32 in a state where the cover member 10d is attached to the steering handle 100d. Then, the visible light output from the LED 32 is incident on the protruding portion 16d along the radial direction. Note that, unlike FIG. 10, the arrangement position of the LED 32 on the substrate 31 may be located upward (radially outward) compared to each embodiment, and the LED 32 may be configured to emit visible light from the upper side to the lower side (from the radially outer side to the radially inner side). Further, the reflecting surface RS may have a curved surface shape instead of the planar shape as shown in FIG. 10.

[0047] Further, for example, as in the cover member 10e shown in FIG. 11, a configuration may be adopted in which a total of two LEDs 32 are arranged outside both ends in the circumferential direction of the protruding portion 16e. In the lower left of FIG. 11, a region Ar4 including a part of the surface S1 of the protruding portion 16e is shown enlarged. A plurality of irregularities are formed on the surface S1, whereby a plurality of reflecting surfaces S1r are formed in the protruding portion 16e when viewed in the circumferential direction. The visible light L1 emitted from the LED 32 is reflected rearward at each reflecting surface S1r. The inclination angle of the reflecting surface S1r can be appropriately adjusted according to the circumferential position of each reflecting surface S1r so that the reflected light is directed rearward. In such a configuration, the protruding portion 16e is arranged at a position shifted in the circumferential direction with respect to the LED 32 in a state where the cover member 10e is attached to the steering wheel 100. The visible light output from the LED 32 enters the protruding portion 16e along the circumferential direction. Also in the configurations of FIGS. 10 and 11 described above, the same effects as those of the first to third embodiments are obtained.

[0048] (E4) In each embodiment, the film portions f1, f1c were formed by screen-printing the layers f11, f13, f14 on the film base material f12, but the present disclosure is not limited thereto. Films corresponding to the layers f11, f13, f14 may be formed in advance, and these films may be attached to the outer surface S2 or the film base material f12 to form the respective layers. Even in such a configuration, the film base material f12 to which the films constituting the layers f11, f13, f14 are attached, that is, the film portions f1, f1c, can be used to manufacture the main body portions 11, 11c by insert molding together with the main member 111. Further, the layers f11, f13, f14 may be formed by mold formation, laser drawing, etching-blasting treatment, or the like. When forming the light diffusion paint layer f14 by mold formation, a diffusion pattern may be provided in the mold in advance.

[0049] (E5) In the second embodiment, the plurality of concavo-convex portions 17 had a configuration in which a plurality of grooves extending in the short side direction of the surface S1 were arranged side by side, but the present disclosure is not limited thereto. A configuration in which regular or irregular pattern-like irregularities such as so-called embossing are formed on the surface S1 may be adopted for the plurality of concavo-convex portions 17.

[0050] (E6) The configurations of the steering wheels 100, 100c, and 100d in each embodiment are merely examples and can be changed in various ways. For example, in each embodiment, the surrounding portion 12 may be omitted. Also, in each embodiment, the illumination device 200 may be configured to emit infrared light (infrared rays) in addition to visible light. In such a configuration, for example, an LED that emits infrared light is assumed to be provided on the substrate 31 separately from the LED 32. By emitting infrared light from the illumination device 200, a part of the driver's body can be clearly photographed by an infrared camera in a dark vehicle interior at night.

[0051] The present disclosure is not limited to the above-described embodiments and can be realized in various configurations without departing from the gist thereof. For example, the technical features in each embodiment corresponding to the technical features in the forms described in the summary of the invention can be appropriately replaced or combined in order to solve some or all of the above-described problems or to achieve some or all of the above-described effects. For example, the film portion f1c of the fourth embodiment may be provided on the cover members 10, 10a, 10b of the first to third embodiments. Also, for example, a configuration in which the concavo-convex portion 17 and the concave portion 18 are mixed on the surface S1 of a single cover member may be adopted. Note that if the technical features in each embodiment are not described as essential in this specification, they can be appropriately deleted.

Explanation of Reference Numerals

[0052] 10... Cover member, 10a... Cover member, 10b... Cover member, 10c... Cover member, 11... Main body part, 11c... Main body part, 12... Surrounding part, 13... Side wall part, 14... Engagement hole, 15... Engagement wall, 16... Protrusion, 16a... Protrusion, 16b... Protrusion, 17... Concavo-convex part, 18... Recess, 19... Display part, 30... Light-emitting part, 31... Substrate, 32... LED, 35... Notch part, 40... Base member, 41... Support part, 42... Coating part, 43... Top part, 44... Engagement claw, 45... Engagement wall, 46... Screw hole, 50... Core metal, 60... Core part, 70... Element layer, 80... Outer skin layer, 90... Screw, 100... Steering handle, 100c... Steering handle, 110... Gripping part, 111... Main member, 120... Spoke part, 130... Boss part, 200... Illumination device, AX... Axis, Ar1... Region, Ar2... Region, Ar3... Region, C1... Recess, S1... Surface, S2... Outer surface, SH... Steering shaft, f1... Film part, f11... Hard coat layer, f12... Film base material, f13... Smoke paint layer, f14... Light diffusion paint layer

Claims

1. A cover member used for an illumination device attached to a steering wheel, the cover member having a visible light transmittance, forming a part of the outer surface of the steering wheel, and being a plate-shaped main body portion that injects the visible light output from the light emitting element included in the illumination device to the outside of the steering wheel, an optical function portion integrated with the main body portion, provided on at least one of the inner surface of the main body portion on the steering wheel side and the outer surface of the main body portion on the outside in the mounted state where the illumination device is mounted on the steering wheel, and realizing at least one of a light guiding function of guiding the visible light output from the light emitting element and a light diffusing function of diffusing the visible light; an optical function portion, A cover member comprising:

2. The cover member according to claim 1, wherein the optical function portion includes a protruding portion protruding from the inner surface and having a visible light transmittance, the tip of the protruding portion faces the light emitting element, and the protruding portion has the light guiding function. A cover member.

3. The cover member according to claim 1, wherein the optical function portion includes a protruding portion protruding from the inner surface and having a visible light transmittance, the protruding portion is disposed at a position where the visible light output from the light emitting element is incident, and the protruding portion has a reflecting surface at an end opposite to the inner surface for reflecting the incident visible light toward the main body portion and has the light guiding function. A cover member.

4. In the cover member according to claim 3, the protruding portion is disposed at a position displaced in the radial direction of the grip portion of the steering wheel in a state where the cover member is attached to the steering wheel with respect to the light emitting element, and the visible light output from the light emitting element is incident on the protruding portion along the radial direction. A cover member.

5. In the cover member according to claim 3, the protruding portion is disposed at a position displaced in the circumferential direction of the grip portion of the steering wheel in a state where the cover member is attached to the steering wheel with respect to the light emitting element, and the visible light output from the light emitting element is incident on the protruding portion along the circumferential direction. A cover member.

6. The cover member according to claim 1, The optical function part is a cover member including a facing surface facing the light-emitting element, which is formed in a concave shape toward the light-emitting element and has the light diffusion function.

7. The cover member according to claim 1, wherein the optical function part is a cover member including a facing surface facing the light-emitting element, on which a plurality of unevennesses are formed and which has the light diffusion function.

8. The cover member according to claim 1, wherein the optical function part is a film part formed on the outer surface of the main body part, which has a predetermined pattern and includes the film part having the light diffusion function.

9. An illumination device attached to a steering wheel, comprising the cover member according to any one of claims 2 to 5, a substrate including the light-emitting element, and a base member to which the cover member and the substrate are attached and which holds the cover member and the substrate, the base member having a support part arranged so as to surround the protruding part. An illumination device comprising the same.

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