Lighting device and steering device using the same

Abstract

A lighting device for reducing light loss when changing the direction of light from a light source within a light guide path, and a deflection device using it. The lighting device radiates light in a first direction and has a light guide path that changes light radiated from a light source in a second direction different from the first direction back to the first direction. A portion of the outer periphery of the light guide path opposite to the light source has a boundary surface that reflects light incident in the second direction. For this boundary surface, the angle of incidence at a point on the boundary surface, i.e., a first point, satisfies the condition of total internal reflection. When the angle formed by the normal to the boundary surface relative to the second direction is defined as an inclination angle, the second angle is smaller than the first angle, and the deviation between the first and second angles is less than a displacement angle. This second angle is the inclination angle at the point on the boundary surface, i.e., the second point, where light emitted from the light source is reflected from the second direction towards the first direction by a predetermined displacement angle.

Description

Technical Field

[0001] This invention relates to a lighting device for use inside a train carriage. Background Technology

[0002] Previously, a lighting device has been proposed that is installed inside a vehicle compartment, such as a steering mechanism (also called a steering wheel), for light-based decoration or information display, etc. (for example, see Patent Document 1 below). In this lighting device, light from a light source such as an LED is directed to a location away from the light source by using a light guide path that uses a light-transmitting component such as acrylic.

[0003] Patent Document 1: Japanese Patent No. 7327321

[0004] To effectively guide light from a light source to the application area, it is generally desirable to configure the light guide path as short and straight as possible. However, due to the configuration of the light source and the application area, or the installation position of the light source, it is sometimes necessary for the light to be reflected within the light guide path. In such cases, problems may arise, such as a portion of the light leaking out of the light guide path depending on the angle of the light incident on it, reducing the efficiency of light guiding, or causing uneven brightness in the application area. Summary of the Invention

[0005] (1) One of the other embodiments of the present invention can be implemented by means of an illumination device that radiates light in a direction centered on a first direction. The illumination device has: a light source that emits light with a second direction different from the first direction as the center of the radiated light; and a light guide path that allows light from the light source to be incident on, and has a boundary surface on a portion of the outer periphery opposite to the light source, the boundary surface reflecting the light incident in the second direction toward the first direction. Here, for the boundary surface, the first angle (θ1) satisfies the total internal reflection condition. This first angle (θ1) is the angle of incidence at the point on the boundary surface, i.e., the first point (P1), where light emitted from the light source towards the second direction is reflected towards the first direction. Furthermore, when the angle formed by the normal (NL) on the boundary surface relative to the second direction is defined as an inclination angle, the second angle (θ2) is smaller than the first angle, and the deviation (Δθ) between the first and second angles is less than a displacement angle (Δα). This second angle (θ2) is the inclination angle at the point on the boundary surface, i.e., the second point (P2), where light emitted from the light source is reflected from the second direction towards the first direction by a predetermined displacement angle. Thus, the angle of incidence of light incident on the second point P2 satisfies the total internal reflection condition, thereby reducing losses when changing the direction of light on the light guide path through reflection at the boundary surface. As a result, light from the light source can be efficiently emitted from the illumination device towards the first direction. Therefore, it is possible to increase the amount of light from the lighting device, or instead of increasing the amount of light, reduce the energy required to radiate light from the light source, thereby suppressing the temperature rise or aging of the light source.

[0006] (2) A second embodiment of the present invention is as an illumination device that radiates light in a direction centered on a first direction. This illumination device includes: a light source that emits light with a second direction different from the first direction as the center of the radiated light; and a light guide path that receives light from the light source and has a boundary surface on a portion of its outer periphery opposite to the light source, the boundary surface reflecting light incident in the second direction toward the first direction. Here, for the boundary surface, a first angle (θ1) satisfies the condition of total internal reflection, the first angle (θ1) being the angle of incidence at a point (P1) on the boundary surface where light emitted from the light source in the second direction is reflected toward the first direction. At least a portion of the connecting shape portion (28) on the outer periphery of the light guide path opposite to the boundary surface has a shape that connects obliquely from the second direction toward the first direction. Thus, the oblique shape on the outer periphery of the light guide path opposite to the boundary surface reduces the amount of light reflected from the light source at a surface existing along the second direction opposite to the boundary surface. Therefore, light that does not undergo total internal reflection at the boundary surface can be reduced, and light from the light source can be utilized more efficiently.

[0007] (3) The present invention can also be implemented as a steering device. This steering device includes: a nearly circular steering wheel for performing steering operations; and the aforementioned lighting device. Here, the first direction of the lighting device is from the steering wheel toward the user performing the steering operation, the second direction is radial toward the outer side of the steering wheel, and the third direction is the circumferential direction of the steering wheel. Thus, a steering device can be provided that has a lighting device capable of radiating light toward the user performing the steering operation over a wide range circumferentially around the steering wheel.

[0008] In this specification, the terminology is generally used in accordance with the following definitions. Where terms are used in a way that does not conform to the following definitions, appropriate explanations will be provided.

[0009] Light: It includes not only visible light, but also electromagnetic waves extending to the far-infrared range (infrared radiation) on the long wavelength side, and electromagnetic waves near the ultraviolet range (near-ultraviolet radiation) on the short wavelength side. As a wavelength region, electromagnetic waves from about 10μm to about 200nm are collectively referred to as light. Infrared and ultraviolet radiation are sometimes referred to as infrared light and ultraviolet light, depending on the context.

[0010] • Light source: A device that emits light. This does not limit the light-emitting mechanism to light bulbs, LEDs, organic ELs, etc.

[0011] • Light emission: The light emitted by a light source. The presence, degree, intensity, or wavelength are not limited by orientation.

[0012] • Emission: The emission of light in a prescribed orientation from a narrow area such as a point source or a small aperture.

[0013] • Incident: The point at which light reaches the boundary between the object and its external surroundings. In this specification, it is used in conjunction with “outgoing” and sometimes refers to the situation where light passes through the boundary and enters the interior of the object.

[0014] • Outgoing: Opposite to “incoming”, it refers to the situation where light inside an object passes through the boundary between the object and the outside and exits the object.

[0015] • Outgoing light: Light emitted from an object that is directed in a specific direction.

[0016] Incident light: Light that travels from a specific direction toward an object and enters the object's interior.

[0017] • Radiation and Emission: The emission of electromagnetic waves or particle streams, including light, by an object is called "radiation." The emission of electromagnetic waves, including light, is called "radiation." Sometimes, the movement of heat to the outside through radiation is called "thermal radiation," and in particular, the movement of heat through the radiation of electromagnetic waves is sometimes called "radiative heat."

[0018] • Illumination: The process of changing the brightness or hue of a constant area through light. Changes in brightness or hue can correspond to the transmission of information, as well as decorative purposes or situations where the purpose is to illuminate or expose the area. Attached Figure Description

[0019] Figure 1 This is a top view showing the external shape of the steering device with the electrical components installed as an embodiment.

[0020] Figure 2 This is a top view showing the external shape of the steering device with the cover, light guide, and housing components removed.

[0021] Figure 3 This is a first exploded perspective view showing the detailed structure of a lighting device assembled with electrical components.

[0022] Figure 4 This is a second exploded perspective view showing the detailed structure of the lighting device.

[0023] Figure 5 It means Figure 2 An explanatory diagram showing the configuration of the light guide component at the V-V section of the steering device.

[0024] Figure 6 It is an explanatory diagram showing the structure of the light guide component and the path of light.

[0025] Figure 7 It is an illustrative diagram that schematically shows the path of light and the reflection at the boundary surface.

[0026] Figure 8 yes Figure 6 VIII vector diagram.

[0027] Figure 9 yes Figure 6 The IX vector diagram.

[0028] Figure 10 It is an explanatory diagram showing the shape of the scattering and reflecting part and the way light is scattered.

[0029] Figure 11 This is an explanatory diagram illustrating the shape of a light guide component that functions as a light guide path. Detailed Implementation

[0030] A. First implementation method: (A1) Overall structure of steering device 100: Figure 1This is a top view showing the external shape of the steering device 100 in the state where the lighting device 200, as an embodiment of the present invention, is installed. The steering device 100 is used in the driver's seat of a vehicle. Examples of vehicles include vehicles equipped with engines, hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), fuel cell vehicles (FCVs), etc. Of course, it is not limited to vehicles, and can also be implemented as a steering device for mobile bodies such as personal mobility vehicles, two-wheeled vehicles, and boats.

[0031] The steering device 100 is part of the steering control system operated by the driver of the vehicle. Figure 1 The diagram shows a steering device 100 in a vehicle, connected to the steering axis SH and in a state where the vehicle is traveling straight (hereinafter also referred to as the "reference state"). Additionally, in... Figure 1 The diagram shows the external structure of the steering device 100 on the side opposite the driver (referred to as the "rear" side). The steering device 100 is configured to rotate about the axis AX of the steering shaft SH. The rotation of the steering device 100 is transmitted to a steering gearbox (not shown) via the steering shaft SH. In this embodiment, the steering device 100 is designed to be approximately circular in shape, but it can be replaced by any shape such as a polygon or an ellipse. Alternatively, it can be an asymmetrical shape such as a so-called D-shape. Furthermore, the shape of the gripping part for steering operation is not limited to a ring shape and can be any shape composed of multiple components arranged in separate positions.

[0032] In this embodiment, the direction along the axis AX of the steering axis SH, corresponding to the vehicle's direction of travel, is referred to as the "front-to-back direction" (forward and rearward). Furthermore, the direction orthogonal to the axis AX that overlaps with the vertical direction (vertical above and vertical below) from the driver's perspective is referred to as the "vertical-upward direction." Additionally, the direction orthogonal to the axis AX that is parallel to the vehicle's left-right direction (width direction) is referred to as the "left-right direction." In this case, left and right are consistent with the direction observed from the driver's seat.

[0033] The steering system 100 rotates clockwise or counterclockwise when viewed from the driver's side for steering operations. Therefore, in the following description, when using the terms "vertical direction" and "left-right direction" to describe the arrangement of the components within the steering system 100, the steering system 100 is assumed to be in a reference state, and each direction is referred to accordingly. Furthermore, the "forward and backward direction" does not change depending on the steering operation state of the steering system 100.

[0034] The steering mechanism 100 includes: an annular grip portion 110; a boss portion 130 disposed approximately at the center of the grip portion 110; three disc portions 120; and an illumination device 200, as an electrical component, disposed in a portion of the grip portion 110. As described later, the illumination device 200 is provided with light-emitting elements such as LEDs. As a light source, light from the light-emitting elements is guided within the illumination device 200, making it possible to visually confirm the illumination status from the outside in an area of ​​a portion of the grip portion 110. This area is referred to as the illumination area IL.

[0035] The grip portion 110 is held by the driver when operating the steering device 100. Because it is the part held by the driver, the grip portion 110 is sometimes referred to as the "steering wheel" or "steering wheel material." In this embodiment, the grip portion 110 has an approximately circular shape. The central axis of the grip portion 110 coincides with the axis AX of the steering shaft SH. The components of the lighting device 200 disposed inside the grip portion 110 are arranged along the shape of the grip portion 110. Therefore, in the following description, the direction along the circular shape of the grip portion 110 is sometimes referred to as the circular direction CW. For ease of illustration, the circular direction CW is... Figure 1 As shown in the image.

[0036] As will be described later, the grip portion 110 of this embodiment has multiple components that overlap in the thickness direction. The outermost layer is formed of an outer skin layer (outer skin layer 80 described later), which is formed of a leather component. Although Figure 1 Not shown in the diagram, but in the grip portion 110, a recess (recess C1 described later) is formed in the upper part, in the reference state, to accommodate a portion of the lighting device 200. A portion of the lighting device 200 is accommodated in the recess C1. In other words, the lighting device 200 is embedded in the recess C1. Furthermore, the opening of the recess C1 is sealed by the lighting device 200.

[0037] Three disc-shaped sections 120 connect the grip section 110 and the boss section 130. The boss section 130 corresponds to the connection point when the steering device 100 is connected to the steering shaft SH. Inside the boss section 130, a folded airbag and inflator (not shown) are housed. Furthermore, the boss section 130 may also house various sensor devices, such as a temperature control circuit constituting a heating device, a sensor for detecting the user's grip on the grip section 110, or a sensor for detecting room temperature. Various operation buttons for vehicle navigation devices or audio systems may also be provided in the three disc-shaped sections 120 and the boss section 130.

[0038] The lighting device 200 has a light source that emits light. In this embodiment, the light emitted by the light source of the lighting device 200 is visible light and infrared light (infrared light). The lighting device 200 can convey various information to the driver by changing the brightness of the visible light in the illuminated area IL. For example, by changing the brightness of the entire or a portion of the illuminated area IL, or by changing its hue, a certain information can be conveyed to the driver. Specifically, by setting the entire or a portion of the illuminated area IL to red, the driver can be prompted to hold the steering wheel. The changes in the brightness or hue of the illuminated area IL of the lighting device 200 are not limited to conveying such information; they can be purely decorative or intended to dispel driver drowsiness. Furthermore, the light emitted from the light source of the lighting device 200 is not limited to visible light; it can also be infrared light. In this embodiment, as described later, both visible light and infrared light are emitted. Infrared light is emitted from the illuminated area IL toward the driver's seat. This infrared light is used to illuminate the driver's body and to capture images of a portion of the driver's body. In the dimly lit carriage at night, the driver's posture can be easily captured by an infrared camera by shining infrared light from the steering device 100 onto the driver without causing glare.

[0039] Figure 2 This is a top view showing the external shape of the steering device 100 after the cover component 10, light guide component 20, and housing component 40 have been removed. As will be described later, in the lighting device 200, a cover component 10 that is transparent to visible light and infrared light is disposed at a position opposite to the driver. In addition, the light guide component 20 and housing component 40, which will be described later, are disposed on the front side of the cover component 10. Figure 2 The steering device 100 schematically shows the state after the cover component 10, the light guide component 20 and the housing component 40 have been removed.

[0040] like Figure 2As shown, if the cover member 10, the light guide member 20, and the housing member 40 are removed, the light-emitting part 30, which is one of the elements constituting the lighting device 200, is exposed. The light-emitting part 30 has a substrate 31 and a plurality of light-emitting elements disposed on the surface of the substrate 31. In this embodiment, the "plural light-emitting elements" include a plurality of first LEDs 32 and a plurality of second LEDs 33 serving as light sources. When viewed from the driver's perspective, the substrate 31 has an arcuate and strip-shaped appearance that curves along the circumference (hereinafter, also simply referred to as "circumferential") of the grip portion 110. Furthermore, the radial direction (the direction orthogonal to the axis AX) of the grip portion 110 will also be simply referred to as "radial" below. The plurality of first LEDs 32 are arranged at predetermined distances from each other along the circumferential direction at the ends near the lower side of the rear side surface of the substrate 31. The first LEDs 32 emit visible light. In this embodiment, visible light LEDs capable of emitting red, green, and blue light are used as the first LEDs 32.

[0041] In contrast, multiple second LEDs 33 emit light in the infrared region. These multiple second LEDs 33 form two groups g1 and g2 arranged spaced apart from each other. Each group g1 and g2 consists of multiple second LEDs 33 that are circumferentially adjacent. Both groups g1 and g2 are located at the end of the rear side surface of the substrate 31 near the upper side. When viewed circumferentially, these two groups g1 and g2 are arranged spaced apart from each other by multiple first LEDs 32.

[0042] (A2) Detailed structure of lighting device 200: Figure 3 This is a first exploded perspective view showing the detailed structure of the lighting device 200. Figure 4 This is a second exploded perspective view showing the detailed structure of the lighting device 200. Figure 3 This is equivalent to an exploded oblique view of the lighting device 200 viewed roughly from the rear to the front. Figure 4 This is equivalent to an exploded oblique view of the lighting device 200 viewed roughly from the front to the rear.

[0043] Figure 5 yes Figure 2 The V-V section shown is a cross-sectional view of the grip portion 110 of the steering device 100. Figure 5 As shown Figure 2 The cross-section at the location of the first LED32 of the lighting device 200 shown is not depicted using section lines to represent various cross-sections for ease of illustration.

[0044] like Figure 3 and Figure 4As shown, the lighting device 200, in addition to the light-emitting part 30 described above, also includes a cover member 10, a light guide member 20, and a housing member 40. The lighting device 200 has a structure in which the light guide member 20 and the light-emitting part 30 are integrated with the cover member 10 in the front-rear direction, separated by the housing member 40. The light guide member 20 is as follows... Figure 3 , Figure 4 As shown, the light guide component 20 has an arc-shaped appearance when viewed from the driver's perspective, matching the configuration positions of the plurality of first LEDs 32. As described later, the light guide component 20 functions as a light guide path to direct the light from the aforementioned first LEDs 32 to the outside.

[0045] like Figure 3 and Figure 4 As shown, the cover component 10 has an outer surface forming portion 11, a surrounding portion 12, and a plurality of engaging walls 15. Figure 3 The outer surface forming part 11 shown is as follows Figure 5 The outer surface of the steering device 100 is formed continuously with the outer skin layer 80. Like the substrate 31 described above, the outer surface forming portion 11 has an arc-shaped, strip-like appearance that curves circumferentially along the grip portion 110 when viewed from the driver's perspective. The outer surface forming portion 11 is transmissive to both visible light and infrared radiation. In this embodiment, the outer surface forming portion 11 has a transmittance of approximately 25% for visible light and approximately 90% for infrared radiation. Furthermore, the transmittance for both visible light and infrared radiation can be any value higher than 0%. In this embodiment, the outer surface forming portion 11 is formed of a black transparent synthetic resin to match the black outer skin layer 80. In addition to protecting the light-emitting portion 30, the outer surface forming portion 11 also has the function of limiting the area through which visible light emitted from the light source, i.e., the first LED 32, is transmitted (in other words, the function of covering areas outside the illumination area) and deflecting the emission direction of infrared radiation emitted from the second LED 33 towards the rear and above the driver's side. The outer surface forming part 11 also has the function of scattering the visible light incident from the first LED 32 in its emission direction when it is emitted to the outside.

[0046] Enclosing part 12 Figure 4 As shown, the inner surface is located on the front side of the outer surface forming portion 11. When the lighting device 200 is assembled (hereinafter, also simply referred to as the "assembled state"), the surrounding portion 12 is configured to surround the support portion 41 and the first light guide portion 21 (described later) over the entire circumference. The support portion 41... Figure 3 and Figure 5The recess C1 of the receiving member 40 shown protrudes rearward, and the first light guide 21 corresponds to a portion of the light guide member 20 housed in the support portion 41. The recess C1 has a groove-shaped structure with an opening at the front of the receiving member 40 and extending circumferentially. The protrusion 13 in the surrounding portion 12, corresponding to a radially spaced sidewall, protrudes from the front side of the outer surface forming portion 11, i.e., the inner side, toward the depth direction of the recess C1. "Depth direction of the recess C1" in this embodiment is as follows: Figure 3 and Figure 5 Therefore, it is roughly consistent with the front and back directions. For example... Figure 4 As shown, a plurality of engaging holes 14 are formed in the protrusion 13. In the assembled state, engaging claws 44 provided on the outer peripheral surface of the support portion 41 of the receiving member 40 engage with the engaging holes 14 (see reference). Figure 3 The engagement is achieved through a series of actions: when the cover member 10 is pressed into the receiving member 40, the protrusion 13 elastically deforms along the shape of the engaging claw 44, passes over the engaging claw 44, and returns to its original shape, thereby allowing the engaging claw 44 to engage in the engaging hole 14. This construction, which utilizes the elastic deformation of a component to fix one component to another, is called a snap-fit ​​engagement. Similarly, the multiple engaging walls 15 provided on the cover member 10, such as... Figure 4 As shown, the cover member 10 has a forward-protruding, wall-like, elastically deformable shape, with a locking hole in the locking wall 15 and a locking claw in the locking wall 45 engaging in a snap-fit ​​relationship. In this way, the cover member 10 is also fixed to the receiving member 40.

[0047] The housing member 40 houses and holds the light guide member 20 and the light-emitting part 30 mounted on its front side, and holds the cover member 10 mounted on its rear side. Furthermore, details regarding the mounting configuration of the housing member 40, the light guide member 20, and the light-emitting part 30 (substrate 31) will be described later. Figure 3 and Figure 4 As shown, the receiving member 40, when viewed from the driver's perspective, has an arc-shaped, strip-like appearance that curves along the annular direction CW. In this embodiment, the receiving member 40 is constructed as a single component made of ABS resin. It may also be constructed as a single component made of PC resin, replacing ABS resin. Alternatively, it may be constructed as a composite component combining multiple components. As described above, a continuous recess C1 in the annular direction CW is formed on the rear side surface of the receiving member 40. Figures 3 to 5 As shown, on the front side of the receiving member 40, a cover portion 42, which is continuous in the annular direction CW, is provided on the upper and lower sides, separated by a recess C1. The cross-sectional shape of the outer surface of the cover portion 42 is as follows: Figure 5As shown, it has a shape with an acute angle between the upper surface and the lower surface separated by the top 43. The covering portion 42 is covered by the outer skin layer 80, which will be described later.

[0048] In the recess C1, a through hole 46 extending in the thickness direction is formed in the portion corresponding to the light guide component 20. For example... Figure 5 As shown, a first light guide portion 21 of a light guide component 20 is inserted into the aforementioned through hole 46. (As indicated...) Figure 3 and Figure 5 As shown, the aforementioned support portion 41 is provided in the recess C1, surrounding the through hole 46 into which the first light guide portion 21 is inserted. The support portion 41 and... Figure 4 Similarly, the surrounding portion 12 of the cover member 10 shown is formed to protrude rearward in such a way that it surrounds the through hole 46 and the side of the first light guide portion 21 inserted into the through hole 46 over the entire circumference. Figure 3 As shown, the support portion 41 has a flat cylindrical shape with an arc-shaped bend. As described above, a plurality of engaging claws 44 are provided on the outer peripheral surface of the support portion 41, and the engaging claws 44 engage with the engaging holes 14 of the cover component 10 in the assembled state. The support portion 41 suppresses the positional displacement of the light guide component 20, including the first light guide portion 21, in the up-down and left-right directions.

[0049] The first LED 32 or second LED 33 of the lighting device 200, along with other electronic components, are mounted on the substrate 31. Power supply cables and signal cables are connected to the substrate 31. The power supply cables are used to supply the required power from an external source, such as the vehicle body. The signal cables are used to exchange control signals between the vehicle-side electronic control unit (ECU) and the substrate 31. Illustrations of these cables are omitted. The control signals include signals that control the blinking of the first LED 32 or second LED 33, etc. Furthermore, the exchange of control signals can be performed via short-range communication such as Bluetooth (registered trademark), and power supply can also be performed via non-contact power supply utilizing magnetic field coupling, etc.

[0050] (A3) Detailed structure of the grip 110: Next, the structure of the grip portion 110 will be described in detail. As already explained, the grip portion 110 houses the lighting device 200, but the lighting device 200 is located in the upper part of the grip portion 110 when the steering device 100 is in the reference state. Figure 1 The location shown as the lighting area IL in the diagram represents the area where the lighting device 200 is not installed. The cross-sectional structure of the portion where the lighting device 200 is not installed is similar to that of the portion where the lighting device 200 is not installed. Figure 5 The cross-sectional structure of the part where the lighting device 200 is installed is the same.

[0051] like Figure 5 As shown, the grip portion 110, despite the difference in whether or not it includes the aforementioned lighting device 200, has a core 50, a core 60, a component layer 70, and an outer skin layer 80 throughout its circumference. In this embodiment, the core 50 is a component distinct from the housing member 40, and functions as a heat dissipation target component that receives heat movement from the high-temperature part. In this embodiment, as... Figure 5 As shown, the back side of the substrate 31 of the light-emitting part 30 and the core 50 are joined by a heat-conducting member 300 and mounted on the substrate 31. The heat generated by the first LED 32 or the second LED 33 is conducted to the core 50 via the heat-conducting member 300. As a result, the heat generated by electronic components and the like mounted on the substrate 31 is dissipated to the core 50, suppressing the temperature rise of the substrate 31 and thus the light-emitting part 30.

[0052] The core 50 is made of metal and serves as the skeleton of the grip portion 110. In this embodiment, the core 50 is made of aluminum alloy. Alternatively, instead of aluminum alloy, the core 50 can be formed of any type of metal such as magnesium alloy or steel. The core portion 60 is configured to cover the entire core 50 except for the rear surface H1, forming the core of the grip portion 110. The core portion 60 is formed of a soft synthetic resin with cushioning properties. Specifically, in this embodiment, the core portion 60 is formed of a soft foam material such as polyurethane foam. The element layer 70 partially covers the core portion 60.

[0053] The element layer 70 is a layer in which heating wires constituting a heating device are disposed or electrodes for detecting grip are used. For example, it is formed from a conductive fabric with a surface treatment such as a carbon coating or metal plating applied to the fiber fabric. Figure 5 As shown, in the portion of the grip 110 where the lighting device 200 is installed, the element layer 70 also covers a portion of the base component. The outer surface of the element layer 70 and the outer surface of a portion of the receiving component 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 cover portion 42 of the receiving component 40, and the inner side of the recess C1 of the receiving component 40. Figure 5 As shown, the end portion of the leather component constituting the outer skin layer 80 is received in the recess C1. The outer skin layer 80 is formed of the leather component. In this embodiment, the leather component is made of natural leather such as top-grain leather or split leather separated from top-grain leather. Alternatively, the leather component may replace natural leather and be made of any type of leather material such as synthetic leather or artificial leather.

[0054] The components of the aforementioned steering device 100 are assembled in roughly the following manner. First, the cover component 10, the light guide component 20, the light-emitting part 30, and the housing component 40 are prepared respectively. Then, the light guide component 20 and the light-emitting part 30 are installed on the back side (front side in the assembled state) of the housing component 40. The light guide component 20 and the light-emitting part 30 are fixed to the housing component 40 by... Figure 3 and Figure 4 The three screws 90 shown are housed in the cutout 35 provided on the upper edge of the substrate 31 and are screwed into the screw holes (not shown) provided in the housing member 40. Hereinafter, the structure in which the light guide member 20 and the light-emitting member 30 are mounted in the housing member 40 in this manner will be referred to as a sub-assembly.

[0055] Next, the sub-assembly is joined to the core 50. For this purpose, the core 60 and element layer 70 are first formed by a method such as two-color molding, surrounding the core 50. The component obtained in this manner is referred to as the "steering wheel material." On the outer surface of the component, which is integrated with the steering wheel material by fastening the sub-assembly to the core 50 using screws (not shown), a leather component is wound around to form an outer leather layer 80. The outer leather layer 80 can be formed, for example, by winding multiple leather material components (parts) circumferentially. Next, adhesive is applied to the wall surface of the recess C1, causing the end portion of the outer leather layer 80 to bend along the shape of the cover portion 42 and be received in the recess C1, thus adhering the end portion to the wall surface of the recess C1. Next, the cover component 10 is inserted into the recess C1. The cover component 10 is fixed to the receiving component 40 by the aforementioned snap-fit ​​engagement. The steering device 100 of this embodiment is formed by connecting the grip portion 110, which is formed in this manner, to the boss portion 130 via the disc portion 120. Furthermore, the method or process for forming the steering device 100 is not limited to this, as long as an appropriate method or process is adopted according to the material, structure, etc. of each component.

[0056] (A4) Structure and function of light guide component 20: Next, mainly utilize Figure 5 , Figure 6 The structure and function of the light guide component 20, which guides light from the first LED 32, will be described. The light guide component 20 guides the light (visible light) emitted from the first LED 32 toward the cover component 10. In this embodiment, the light guide component 20 is formed of polycarbonate (PC) resin. Alternatively, it may be formed of acrylic resin instead of PC resin. To explain the direction of light from the light guide component 20, the following will... Figure 5 The direction from the center of the grip portion 110 toward the cover member 10 is referred to as the first direction D1. Furthermore, the direction orthogonal to the first direction D1, i.e., the upper part of the figure, will be referred to as the second direction D2.

[0057] like Figure 5 As shown, the light guide component 20 has an appearance shape with an approximate J-shape in cross-section along the axis AX. The approximate J-shape is a shape in which a first light guide portion 21 along the first direction D1 and a second light guide portion 22 shorter than the first light guide portion 21 and along the second direction D2 are connected by an arc-shaped portion. In this embodiment, by reflection at the boundary surface between this arc-shaped portion and the outside, the direction of light incident from the first LED 32 to the light guide component 20 is changed from the second direction D2 to the first direction D1. Therefore, this arc-shaped portion is called the changing portion 23. Furthermore, the length of the first light guide portion 21 along the first direction D1 and the length of the second light guide portion 22 along the second direction D2 are arbitrary.

[0058] like Figures 3 to 5 As shown, the first light guide portion 21 has a radiating surface S1 for radiating visible light from the light guide member 20 to the cover member 10. The second light guide portion 22 has an incident surface S2 for the visible light emitted from the first LED 32 to enter. Figure 5 As shown, the incident surface S2 is positioned above the first LED 32 (second direction D2). Visible light emitted from the first LED 32 is incident on the incident surface S2. The second direction D2 is... Figure 5 In this state, it is equivalent to above or approximately above. In this embodiment, the first direction D1 and the second direction D2 are orthogonal to each other, but they can also be angles other than orthogonal.

[0059] The changing section 23 substantially changes the direction of light incident from each of the first LEDs 32 from the second direction D2 to the first direction D1 by total internal reflection at a boundary surface provided on a portion of the outer periphery of the light guide member 20, and the light is scattered to a predetermined range extending to the adjacent directions of the plurality of first LEDs 32, i.e., the annular direction CW. To achieve this change in the direction of light from the first LEDs 32, the boundary surface provided on a portion of the outer periphery of the light guide member 20 is as follows: Figure 4 As shown, it is arranged corresponding to the entire range of multiple first LEDs 32, that is, continuously arranged in the annular direction CW direction.

[0060] like Figure 4 As shown, multiple scattering and reflecting portions 25 are formed at positions corresponding to each first LED 32 on the boundary surface HM. Each scattering and reflecting portion 25 is positioned in front of each first LED 32 at a corresponding position, i.e., on the optical axis of the first LED 32. Each scattering and reflecting portion 25 has a concave structure with a partial chamfer of the changing portion 23. Figure 5 As shown, in the assembled state, the first light guide 21 is housed within the recess C1. On the other hand, in the assembled state, the second light guide 22 and the alteration part 23 are located on the front side of the housing member 40 and are not housed within the recess C1.

[0061] The following describes the general shape of the light guide component 20, including the scattering and reflecting section 25. Along the optical axis passing through the center of each first LED 32, as shown... Figure 5 As shown, the changing section 23, which connects the first light guide section 21 and the second light guide section 22, is formed in an approximately arc shape connecting the first direction D1 and the second direction D2. The scattering and reflecting section 25, as already explained, is concave in the annular direction CW, but it can also be configured to have an arc shape from the second light guide section 22 to the first light guide section 21 even if it deviates from the optical axis passing through the center of the first LED 32. Therefore, visible light incident from the incident surface S2 onto the second light guide section 22 and directed upwards (second direction D2) undergoes total internal reflection in the scattering and reflecting section 25 of the changing section 23, thereby changing its direction of travel to the rear (first direction D1) and being guided towards the first light guide section 21. In other words, the visible light incident on the second light guide section 22 is configured such that its direction of travel is changed by the changing section 23, and it is scattered in the annular direction CW by the scattering and reflecting section 25, forming light that extends in the annular direction CW.

[0062] As described above, the path of light incident from the first LED 32 is changed in two directions by the changing unit 23. One is the path change from the second direction D2 to the first direction D1, and the other is the path change of light extending in the annular direction CW towards the second direction D2. These will be explained sequentially below.

[0063] Figure 6 This is an explanatory diagram illustrating how the light from the first LED 32, which serves as a light source, is redirected from the second direction D2 to the first direction D1 using the first LED 32 and the light guide member 20. Visible light emitted from the first LED 32 has an inherent orientation and is emitted as an approximately conical beam, but here, its center, i.e., the direction with the greatest light intensity, is referred to as the emission direction of the light from the first LED 32. In this embodiment, the emission direction of the light from the first LED 32 is called the second direction D2. The second direction D2 is approximately perpendicular to the incident surface S2 of the light guide member 20.

[0064] Almost all the light emitted from the first LED 32 enters the second light guide section 22 through the incident surface S2. However, among the light emitted from the first LED 32, there is not only light incident parallel to the second direction D2, but also light that, although having a certain orientation, is incident within a specified angular range relative to the second direction D2, as shown in the figure. In the figure, the light emitted from the first LED 32 towards the second direction D2 and incident on the second light guide section 22 is indicated by the symbol LC; the light incident from the second direction D2 towards the opposite side (front side) of the first direction D1 at a specified angle is indicated by the symbol LM; the light incident from the second direction D2 towards the side (rear side) of the first direction D1 at a specified angle is indicated by the symbol LP; and the light incident more obliquely towards the first direction D1 than the light LP is indicated by the symbol LD. These symbols are used to distinguish each light, similar to the radiated light PC.

[0065] In this embodiment, when the light guide member 20 is cut along a plane containing the center of the light emitted from the first LED 32 and including the first direction D1 and the second direction D2, the cross-section of the changing portion 23 is arc-shaped. The outer periphery of the arc shape, i.e., the side with a larger radius of curvature, functions as the changing portion 23 that changes the direction of light incident on the second light guide member 22. This changing portion 23 becomes the boundary surface between the light guide member 20 with its high refractive index and the air with its low refractive index, where light incident at an angle greater than the critical angle is totally internally reflected. The light guide member 20 in this embodiment is made of polycarbonate with a refractive index of 1.59. Therefore, the critical angle ζ for total internal reflection is: ζ=sin -1 (1 / 1.56)≈39 degrees.

[0066] Therefore, if the angle of incidence relative to the normal at the point where the incident light reaches the arc-shaped boundary surface HM of the changing part 23 is greater than 39 degrees, total internal reflection occurs, the incident light is almost without loss, and its direction is changed towards the first direction D1.

[0067] In the light guide component 20 of this embodiment, due to its high refractive index and the arc-shaped design of the changing section 23, any incident light LC, LM, LP, LD undergoes total internal reflection at the boundary surface HM of the changing section 23, changing its optical path towards the first direction D1. The shape of the boundary surface HM used to cause total internal reflection of each incident light will be described in detail later. After total internal reflection, the light remains unchanged and is reflected directly or further at the boundary surface HM on the outer periphery of the first light guide component 21, reaching the radiating surface S1, where it is refracted and emitted outwards. The light emitted from the radiating surface S1 exits beyond the illumination device 200.

[0068] The reason why most of the light incident on the incident surface S2 of the second light guide section 22 of the light guide member 20 is totally reflected in the changing section 23 is that the changing section 23 has the shape described below. Figure 7 This is an explanatory diagram schematically showing the reflection at the modified part 23. Modified part 23 is actually as follows: Figure 6 The shape shown is an arc, but for ease of explanation, in Figure 7 The diagram schematically illustrates a polygon formed by connecting the tangents at points P1, P2, and P3 where the incident light arrives. In the diagram, point P1 represents the position where light LC, incident in the second direction D2 direction and passing through the center of the first LED 32, reaches the outer periphery of the light guide member 20 at the changing section 23. Similarly, point P2 represents the position where light LP, emitted from the first LED 32, is tilted by a displacement angle Δα relative to the second direction D2 towards the first direction D1, reaches the outer periphery of the light guide member 20 at the changing section 23. Furthermore, point P3 represents the position where light LM, emitted from the first LED 32, is tilted by a displacement angle Δβ relative to the second direction D2 towards the opposite side of the first direction D1, reaches the outer periphery of the light guide member 20 at the changing section 23.

[0069] In this embodiment, the boundary surface HM of the modified part 23 at points P1, P2, and P3 is defined to satisfy the following relationship. That is, for the boundary surface HM of the modified part 23, the incident angle at each point P1 on the boundary surface HM, i.e., the first angle θ1, and the tilt angle θ2 formed by the normal NL at point P2 relative to the second direction D2 satisfy the following relationship.

[0070] [1] The angle of incidence at point P1 on the boundary surface HM, i.e., the first point, where the light emitted from the first LED32 (which is the light source) in the second direction D2 is reflected in the first direction D1, is the first angle θ1 that satisfies the condition of total internal reflection. [2] Let the angle at which the light emitted from the first LED32, which is tilted by a predetermined displacement angle Δα relative to the second direction D2 towards the first direction D1, is reflected towards the second point P2, i.e., the second point P2, be the second angle θ2. At this time, <1> The second angle θ2 is less than the first angle θ1, and, <2> The deviation Δθ between the first angle θ1 and the second angle θ2 is less than or equal to the displacement angle Δα.

[0071] The boundary surface HM of the changing portion 23 of the light guide member 20 in the lighting device 200 of this embodiment satisfies the above-described relationship. Wherein, if the above <1> and <2> are expressed as formulas, then: <1> θ1-θ2=Δθ>0 <2> Δθ < Δα.

[0072] According to this relationship, for the incident angle θ3 towards the second point P2, Using θ3 = θ2 + Δα, It can be deduced that θ3-θ1≥0.

[0073] That is, if the above conditions are met, the incident angle θ3 at the second point P2 is greater than the incident angle θ1 at the first point P1. If the first point P1 satisfies the total internal reflection condition, then the second point P2 also satisfies the total internal reflection condition.

[0074] The relationship related to total internal reflection also holds in the following case: the tilt angle θm of the light LM emitted from the first LED32, which is a light source, that is tilted by a predetermined displacement angle Δβ relative to the second direction D2 towards the side opposite to the first direction D1, at the point P3, the third point, which is reflected from the boundary surface HM towards the first direction D1, is greater than the first angle θ1, and the deviation between the tilt angle θm and the first angle θ1 is less than or equal to the displacement angle Δβ.

[0075] In this embodiment, since the arc shape of the changing portion 23 of the light guide member 20 is set such that the relationship between the incident angle (i.e., the first angle θ1) at the first point P1 in the boundary surface HM and the second angle θ2 at the second point P2 offset from the first point P1 in the first direction D1 is as described above, when light emitted from the first LED 32 in a manner with a predetermined extension (orientation) enters the changing portion 23, the total internal reflection condition is satisfied at the first point P1, and as a result, the total internal reflection condition is also satisfied at the second point P2, thus suppressing light loss during reflection at the boundary surface HM of the changing portion 23. Furthermore, since the shape of the changing portion 23 is selected such that the above-described condition is also satisfied at the third point P3, light loss during reflection at the boundary surface HM of the changing portion 23 can also be suppressed.

[0076] (A5) Light scattering at point 25 of the scattering and reflecting section: Next, using Figures 8 to 10 This explains the scattering of light caused by the scattering and reflecting section 25. As already explained, the scattering and reflecting section 25 is provided on the boundary surface HM of the changing section 23, so that the light from the first LED 32 is mainly scattered in the annular direction CW, and guided to a wider range of the illumination area IL through a smaller number of first LEDs 32.

[0077] Figure 8 yes Figure 6 VIII vector diagram, Figure 9 yes Figure 6 The IX-vector diagram. Additionally... Figure 10 The upper part (A) is Figure 8 XA-XA vector diagram, Figure 10 The next section (B) is Figure 9The XB-XB vector diagram. As shown in the figure above, the scattering and reflecting portion 25 is designed to be concave inward with a predetermined curvature relative to the boundary surface HM of the outer periphery of the changing portion 23. Therefore, as Figure 8 and Figure 9 As shown, the incident light is scattered and emitted to the outside.

[0078] like Figure 10 As shown in (A), the light incident on the scattering and reflecting part 25 is scattered and extended in the circular direction CW in response to the curved surface.

[0079] like Figure 10 As shown in (A), if light from the first LED 32 is displaced in the left-right direction and incident on the scattering and reflecting section 25, due to the difference in the left-right radiation angle of the first LED 32 and the difference in the angle of the normal NL caused by the curvature of the scattering and reflecting section 25, the degree of scattering in the left-right direction increases as the light moves away from the center, and the light from the first LED 32 is more widely dispersed in the annular direction CW of the illumination area IL. On the other hand, as Figure 10 As shown in (B), the light scattered by the scattering and reflecting section 25 has a smaller degree of scattering in the vertical direction, falling within the width of the illumination area IL. As a result, the large illumination area IL can be illuminated more uniformly and brightly by the multiple first LEDs 32 arranged at intervals.

[0080] (A6) Shape and function of connecting part 28: In this embodiment, the inner side of the arc-shaped change portion 23, i.e., the side with a smaller radius of curvature (hereinafter referred to as the connecting shape portion 28), is arc-shaped, mimicking the shape of the outer side. For this inner side shape, if the connecting shape portion 28 is replaced by a right-angled bend shape pa, as... Figure 6 As shown, the incident light LD is reflected at point pa, and as indicated by the dashed line Ld, it does not undergo total internal reflection at the boundary surface HM of the changing section 23, and is emitted outward. The light output to the outside does not reach the radiating surface S1, and therefore the light intensity of the illumination device 200 decreases accordingly. In this embodiment, the connecting shape section 28 is also provided as an arc shape, so the generation of this loss can be reduced, and the brightness of the illumination device 200 can be increased accordingly, or the power consumption can be suppressed compared with conventional illumination devices of the same brightness.

[0081] In this embodiment, the shape of the connecting shape portion 28 mimics the outer peripheral shape of the changing portion 23. However, since the connecting shape portion 28 does not require total internal reflection to change the direction of light travel, its shape can be any shape as long as it does not obstruct the travel of light emitted from the first LED 32. As long as the shape protrudes less than the corner shape pa, it is beneficial to increase the amount of light emitted from the radiating surface S1. For example, it can also be a shape with the corner of the corner shape pa beveled or a simple semi-circular shape. That is, at least a portion of the connecting shape portion 28 only needs to be a shape that is connected obliquely from the second direction to the first direction. As long as the connecting shape portion 28 is set to a shape with a smaller protrusion than the corner shape pa, the passage cross-sectional area of ​​the light guide member 20 will not have a narrow part, and in this respect, it is also easy to ensure the amount of light.

[0082] (A7) Functions and Effects: As explained above, in this embodiment, as detailed in item (A5), the shape of the changing portion 23 is designed to easily generate total internal reflection at the boundary surface HM, and the connecting portion 28 is designed to have a small protrusion. As a result, the light leaking out from the changing portion 23 is reduced due to reflection at this portion, and narrow portions are less likely to form in the light guide member 20. These structures, combined with each other, can increase the proportion of light incident from the incident surface S2 that exits from the radiating surface S1 for the light guide member 20 as a whole. As a result, the brightness of the illumination area IL can be increased. Of course, instead of increasing the light amount, the light emission of the first LED 32 can be reduced, thereby reducing the power required to ensure the same light amount. As long as the power can be reduced, the heating or aging of the first LED 32 can be suppressed.

[0083] In this embodiment, a recessed scattering and reflecting portion 25 is formed on the boundary surface HM of the changing portion 23. Preferably, the recessed shape of this scattering and reflecting portion 25 is such that it is recessed with a predetermined radius of curvature in the annular direction CW, conforming to the shape of the arc of the boundary surface HM of the changing portion 23. This is because the illumination area IL is an elongated shape in the annular direction CW, so the degree of light scattering in the second direction is less than the scattering in the annular direction CW. In this embodiment, as... Figure 6 As shown, the scattering and reflecting portion 25 is designed to be recessed into the interior of the light-guiding component 20 beyond the boundary surface HM outside the scattering and reflecting portion 25, but it can also be an outwardly convex arc shape. That is, in this embodiment, the scattering and reflecting portion 25 is designed as a saddle shape. Of course, it is also acceptable for the scattering and reflecting portion 25 to be designed as a concave or flat shape in the direction intersecting the annular direction CW, thereby expanding the scattering range in the second direction.

[0084] In the above description, the first LED 32 was used as an example as a light source, but the same applies to the second LED 33. As for whether the reflection of the infrared light emitted from the second LED 33 at the changing part 23 of the light guide member 20 satisfies the condition of total internal reflection, since the difference in the critical angle caused by the wavelength is small, it is roughly the same as the case of visible light, and the shape of the boundary surface HM can be defined in the same way as for visible light.

[0085] B. Other implementation methods: (1) One of the other embodiments of the present invention can be implemented by means of an illumination device that radiates light in a direction centered on a first direction. The illumination device has: a light source that emits light with a second direction different from the first direction as the center of the radiated light; and a light guide path that allows light from the light source to be incident on, and has a boundary surface on a portion of the outer periphery opposite to the light source, the boundary surface reflecting the light incident in the second direction toward the first direction. Here, for the boundary surface, the first angle (θ1) satisfies the total internal reflection condition. This first angle (θ1) is the angle of incidence at the point on the boundary surface, i.e., the first point (P1), where light emitted from the light source towards the second direction is reflected towards the first direction. Furthermore, when the angle between the normal (NL) on the boundary surface and the second direction is defined as the tilt angle, the second angle (θ2) is smaller than the first angle, and the deviation (Δθ) between the first and second angles is less than a displacement angle. This second angle (θ2) is the tilt angle at the point on the boundary surface, i.e., the second point (P2), where light emitted from the light source is reflected from the second direction towards the first direction by a predetermined displacement angle (Δα). Thus, the angle of incidence of light incident on the second point P2 satisfies the total internal reflection condition, thereby reducing losses when changing the direction of light on the light guide path through reflection at the boundary surface. As a result, light from the light source can be efficiently emitted from the illumination device towards the first direction. Therefore, it is possible to increase the amount of light from the lighting device, or instead of increasing the amount of light, reduce the energy required to radiate light from the light source, thereby suppressing the temperature rise or aging of the light source.

[0086] Here, the first point is the point where light emitted from the light source in the second direction is reflected back towards the first direction. Conversely, the second point is any point on the boundary surface where light, tilted at a predetermined displacement angle from the second direction towards the first direction, is reflected back towards the first direction. Other positional relationships are arbitrary. It is conceivable that the configuration of the first and second points is infinite, as long as one set of the first and second points satisfies the aforementioned relationship. Of course, it is also acceptable to use multiple possible reflection points on the boundary surface as the second point, determining the shape of the boundary surface in a manner that satisfies the aforementioned relationship.

[0087] As long as the above conditions are met, the shape of this boundary surface can be composed of multiple planes or one or more curved surfaces. Planes and curved surfaces can also be combined. In this way, the boundary surface can be designed and manufactured to correspond to the orientation of light emitted from the light source, etc., enabling various lighting devices that emit light efficiently.

[0088] (2) In the above structure, the third angle is greater than the first angle for the boundary surface, and the deviation between the third angle and the first angle is less than or equal to the displacement angle Δβ. This third angle is the tilt angle at the point where light emitted from the light source is reflected towards the first direction by a predetermined displacement angle Δβ relative to the second direction. In this way, light emitted from a light source radiating from the second direction as the center of the emitted light and tilted by a displacement angle Δβ in the direction opposite to the first direction can also be totally internally reflected at the boundary surface, enabling efficient utilization of the light from the light source.

[0089] (3) In the above structure, the outer periphery of the light guide path may have a connecting shape portion that is inclined from the second direction to the first direction on the side opposite to the boundary surface. In this way, the outer periphery of the light guide path is inclined on the side opposite to the boundary surface, which can reduce the light reflected from the light source at the surface that exists along the second direction on the side opposite to the boundary surface. Therefore, it is possible to reduce the light that does not undergo total internal reflection at the boundary surface, and to utilize the light from the light source more efficiently.

[0090] (4) A second embodiment of the invention is as an illumination device that radiates light in a direction centered on a first direction. This illumination device includes: a light source that emits light with a second direction different from the first direction as the center of the radiated light; and a light guide path that receives light from the light source and has a boundary surface on a portion of its outer periphery opposite to the light source, which reflects light incident in the second direction toward the first direction. Here, for the boundary surface, a first angle (θ1) satisfies the condition of total internal reflection. This first angle (θ1) is the angle of incidence at a point (P1) on the boundary surface where light emitted from the light source in the second direction is reflected toward the first direction. At least a portion of the connecting shape portion (28) on the outer periphery of the light guide path opposite to the boundary surface has a shape that connects obliquely from the second direction toward the first direction. Thus, the oblique shape on the outer periphery of the light guide path opposite to the boundary surface reduces the amount of light reflected from the light source at surfaces existing along the second direction opposite to the boundary surface. Therefore, light that does not undergo total internal reflection at the boundary surface can be reduced, and light from the light source can be utilized more efficiently.

[0091] The shape of the reflective surface of the above-mentioned lighting device can be set to have the features of (1) or (2) mentioned above. In this way, the light that undergoes total internal reflection at the boundary surface can be increased, and the light from the light source can be utilized more efficiently.

[0092] (5) In the above structure, such as Figure 11 As shown, the light guide component 20B, which functions as a light guide path, can be formed in the following manner. Figure 11 This is an explanatory diagram showing an example of the light guide component 20B in oblique view form, used to illustrate the dimensions, etc., of each part. The light guide component 20B is formed of the same material and shape as in the first embodiment, and the first direction D1 and the second direction D2 are approximately orthogonal. The light guide component 20B, functioning as a light guide path, includes: a first light guide portion 21 that guides light reflected at the boundary surface along the first direction D1; a second light guide portion 22 that guides light from the light source along the second direction D2; and a changing portion 23 that connects the first light guide portion 21 and the second light guide portion 22, changing the direction of light incident from the light source onto the second light guide portion 22 towards the second direction D2 back to the first direction D1. Here, the length LLC of the third direction CW along the direction approximately orthogonal to the second direction D2 and the first direction D1 can be more than twice the width W1 of the second light guide 22 in the first direction D1 and the width W2 of the first light guide 21 in the second direction D2. The changing section 23 has a scattering and reflecting section 25, which scatters light guided from the light source along the second direction D2 in the third direction CW. In this way, light from the light source can be more widely scattered in the third direction CW and emitted to the outside.

[0093] (6) In the above structure, multiple light sources arranged along a third direction can be set apart from each other. In this way, the non-uniformity of light scattered to the outside in the third direction can be reduced.

[0094] (7) The present invention can also be implemented as a steering device. This steering device has: a steering wheel of approximately circular shape for performing steering operations; and an illumination device as described in any one of (1) to (6) above. Here, the first direction of the illumination device may be a direction from the steering wheel toward the user performing the steering operation, the second direction may be a radial direction toward the outer side of the steering wheel, and the third direction may be the circumferential direction of the steering wheel. Thus, a steering device can be provided that has an illumination device capable of radiating light toward the user performing the steering operation over a wide range circumferentially around the steering wheel.

[0095] This invention is not limited to the embodiments described above, and can be implemented in various structures without departing from its spirit. For example, the technical features of each embodiment corresponding to the technical features described in the Summary of the Invention section can be appropriately replaced or combined to solve some or all of the above-described problems, or to achieve some or all of the above-described effects. Furthermore, any technical feature that is not described as essential in this specification can be appropriately deleted. For example, a part of the structure implemented in hardware in the above embodiments can be implemented in software.

[0096] Explanation of the label

[0097] 10…Cover component, 11…Outer surface forming part, 12…Enclosing part, 13…Protrusion, 14…Matching hole, 15…Matching wall, 20, 20B…Light guide component, 21…First light guide part, 22…Second light guide part, 23…Change part, 25…Scattering and reflecting part, 28…Connecting shape part, 30…Light emitting part, 31…Substrate, 32…First LED, 33…Second LED, 34…Diffuser plate, 35…Cut part, 39…Pad, 40, 40C, 40D…Receiving component, 41…Support, 42…Cover, 43…Top, 44…Engaging claw, 45…Engaging wall, 46…Through hole, 50…Core, 60…Core section, 70…Component layer, 80…Outer skin layer, 90…Screw, 100…Steering device, 110…Grip, 120…Disc section, 130…Boss section, 200…Lighting device, 300…Heat-conducting component

Claims

1. A lighting device (200) that radiates light in a direction centered on a first direction (D1). The lighting device (200) has: Light sources (32, 33) emit light with a second direction (D2) different from the first direction as the center of their radiating light; and A light guide path (20) is provided for light incident from the light source, and a portion of its outer periphery opposite to the light source has a boundary surface (HM) that reflects light incident in the second direction toward the first direction. For the boundary surface The first angle (θ1) satisfies the condition for total internal reflection. This first angle (θ1) is the angle of incidence at the first point (P1) on the boundary surface where light emitted from the light source in the second direction is reflected in the first direction. When the angle between the normal (NL) on the boundary surface and the second direction is set as the tilt angle, the second angle (θ2) is smaller than the first angle, and the deviation (Δθ) between the first angle and the second angle is less than the displacement angle (Δα). The second angle (θ2) is the tilt angle at the point (P2) on the boundary surface where the light emitted from the light source is reflected from the second direction toward the first direction by a predetermined displacement angle.

2. The lighting device according to claim 1, wherein, For the boundary surface, the third angle (θm) is greater than the first angle, and the deviation between the third angle and the first angle is less than or equal to the displacement angle (Δβ). The third angle (θm) is the tilt angle at the point (P3) where light emitted from the light source is reflected from the second direction toward the opposite side of the first direction by a predetermined displacement angle (Δβ) toward the first direction.

3. The lighting device according to claim 1, wherein, The outer periphery of the light guide has a connecting shape portion (28) that is inclined from the second direction to the first direction on the side opposite to the boundary surface.

4. A lighting device (200) that radiates light in a direction centered on a first direction (D1). The lighting device (200) has: Light sources (32, 33) emit light with a second direction (D2) different from the first direction as the center of their radiating light; and A light guide path (20) is provided for light incident from the light source, and a portion of its outer periphery opposite to the light source has a boundary surface (HM) that reflects light incident in the second direction toward the first direction. For the boundary surface, the first angle (θ1) satisfies the condition for total internal reflection. This first angle (θ1) is the angle of incidence at a point (P1) on the boundary surface where light emitted from the light source in the second direction is reflected in the first direction. At least a portion of the connecting shape portion (28) located on the opposite side of the boundary surface in the outer periphery of the light guide has a shape that is inclined from the second direction to the first direction.

5. The lighting device according to any one of claims 1 to 4, wherein, The boundary surface is composed of multiple planes or one or more curved surfaces.

6. The lighting device according to any one of claims 1 to 4, wherein, The first direction and the second direction are approximately orthogonal. The light guide path includes: a first light guide (21) that guides the light reflected from the boundary surface along the first direction; and a second light guide (22) that guides the light from the light source along the second direction. And a changing section (23) that connects the first light guide section and the second light guide section, changing the direction of light incident from the light source onto the second light guide section in the second direction to the first direction. The length (LLC) of the third direction (CW) of the light guide path, which is approximately orthogonal to the second direction and the first direction, is more than twice the width (W1) of the second light guide portion in the first direction and the width (W2) of the first light guide portion in the second direction. The alteration section has a scattering and reflecting section (25) that scatters light guided from the light source along the second direction toward the third direction.

7. The lighting device according to claim 6, wherein, Multiple light sources arranged along the third direction are set apart from each other.

8. A steering device (100) comprising: A nearly circular steering wheel (110) for steering operations; and The lighting device (200) according to claim 6. The first direction is from the steering wheel toward the user performing the steering operation. The second direction is radial towards the outer side of the steering wheel. The third direction is the circumferential direction of the steering wheel.

Images