JP7747576B2 - Vehicle interior lighting system - Google Patents

Description

The present invention relates to a vehicle interior lighting device.

Conventionally, there are devices installed in the passenger compartment of an automobile to illuminate the interior of the vehicle. Patent Document 1 discloses technology related to an interior lighting device that turns on and off when part of the human body touches the light-emitting surface of the lens facing the interior of the vehicle. In this technology, part of the light-transmitting portion of the lens and the annular electrode portion of the bus bar come into contact via part of the housing (inner cover). The bus bar also comes into contact with an electrode pad on a circuit board that is conductive to the control unit. Therefore, when part of the human body touches the light-emitting surface of the lens, the control unit can detect a change in capacitance between the electrode portion and the human body and switch the light source on and off.

Japanese Patent Application Laid-Open No. 2022-12257

In the vehicle interior lighting device disclosed in Patent Document 1, dimensional variations in components can occur between products due to various manufacturing conditions. Therefore, for example, dimensional errors in the housing can cause a loss of adhesion between the electrode portion of the bus bar and the housing, which can result in an insufficient change in capacitance between the electrode portion and the human body when the human body touches the light irradiation surface. This insufficient change in capacitance is undesirable because it makes it difficult for the control unit to detect the change in capacitance and, ultimately, to properly switch the light source on and off.

The present invention was made in consideration of the problems inherent in the prior art. The object of the present invention is to provide a vehicle interior lighting device that stably detects changes in capacitance when switching between on and off.

An interior lighting device according to one aspect of the present invention includes a light source, a lens having a light-transmitting portion that transmits light emitted from the light source toward the interior of the vehicle cabin, a housing having an annular lens contact surface that is in surface contact with the outer periphery of the light-receiving surface of the light-transmitting portion and a busbar contact surface opposite the lens contact surface, a conductive busbar having an annular electrode portion that conforms to the shape of the busbar contact surface, a holder having an annular contact end portion that conforms to the shape of the electrode portion and that holds the busbar by bringing the contact end portion into contact with the electrode portion, and a control unit that switches the light source on and off in response to changes in capacitance between the electrode portion and a part of the human body that touches the light-irradiating surface of the light-transmitting portion, wherein the electrode portion is a flat plate with one main plane that is in surface contact with the busbar contact surface and the other main plane that faces the contact end portion, and one of the electrode portion or the contact end portion has a biasing portion that applies a biasing force to the other.

1 is an external perspective view of a vehicle interior lighting device according to a first embodiment. 1 is an exploded perspective view of a vehicle interior lighting device according to a first embodiment. FIG. 2 is a perspective view of a housing according to the first embodiment. FIG. 2 is a perspective view of a first bus bar according to the first embodiment. FIG. 2 is a perspective view of a first holder in the first embodiment. 6 is a partial cross-sectional view of the vehicle interior lighting device corresponding to the cross section taken along line VI-VI in FIG. 1. 7 is a partial cross-sectional view of the vehicle interior lighting device corresponding to the cross section VII-VII of FIG. 1. FIG. 10 is a perspective view of a second bus bar according to a second embodiment. FIG. 11 is a perspective view of a third bus bar in the third embodiment. FIG. 10 is a perspective view of a second holder in the fourth embodiment. FIG. 10 is a partial cross-sectional view showing an engagement groove and a first spring portion in a fourth embodiment. FIG. 13 is a perspective view of a fourth bus bar in the fifth embodiment. FIG. 13 is a perspective view of a third holder in the fifth embodiment. FIG. 13 is a partial cross-sectional view showing a wide portion of a third side wall portion in a fifth embodiment. FIG. 13 is a partial cross-sectional view showing a wide portion of a second side wall portion in a fifth embodiment. FIG. 20 is a perspective view of a fifth bus bar in the sixth embodiment. FIG. 23 is a perspective view of a sixth bus bar in the seventh embodiment. FIG. 23 is a perspective view of a fourth holder in the seventh embodiment. FIG. 13 is a partial cross-sectional view showing a wide portion in a seventh embodiment. FIG. 19 is a perspective view of a seventh bus bar in the eighth embodiment. FIG. 20 is a perspective view of a fifth holder in the eighth embodiment. FIG. 20 is a partial cross-sectional view showing a fifth biasing portion in the eighth embodiment.

The vehicle interior lighting device according to each embodiment will be described in detail below using the drawings. Note that the dimensional proportions in the drawings have been exaggerated for the sake of explanation and may differ from the actual proportions.

(First embodiment)
1 is a perspective view showing the exterior of a vehicle interior lighting device 1 according to a first embodiment. The vehicle interior lighting device 1 is installed in the interior of a vehicle such as an automobile to illuminate the interior of the vehicle. The vehicle interior lighting device 1 has a capacitive touch switch structure that allows an occupant to switch the vehicle interior lighting device 1 on and off by touching a light irradiation surface 13c of a lens 13, which is a part of the vehicle interior lighting device 1.

The following figures illustrate directions based on the XYZ coordinate system. The Z direction corresponds to the light irradiation direction perpendicular to the light irradiation surface 13c of the lens 13, and, referring to Figure 2, also follows the assembly direction of the elements that make up the vehicle interior lighting device 1. The X and Y directions are perpendicular to each other and are both perpendicular to the Z direction. Of these, the X direction corresponds to the parallel arrangement direction of the two light sources 20.

Figure 2 is an exploded perspective view of the vehicle interior lighting device 1. The vehicle interior lighting device 1 includes a substrate 10, a prism 11, a housing 12, a lens 13, a first bus bar 14, a first holder 15, a console 16, and a bezel 17.

The board 10 includes a light source 20, an electrode pad 21, a control unit 22, and a connector unit 23. The light source 20 is, for example, an LED (light-emitting diode) that emits light for illumination. In this embodiment, two light sources 20 are provided. The electrode pad 21 contacts a portion of the board connection portion 14b of the first bus bar 14. In this embodiment, a first bus bar 14 is provided for each light source 20, and two electrode pads 21 are provided on the same surface of the board 10 as the light source 20. The control unit 22 controls the overall functions of the interior lighting device 1 and includes at least a microcomputer that controls electrostatic touch. The control unit 22 is electrically connected to the electrode pad 21. When a part of the human body, such as a fingertip F (see Figure 6, etc.), touches the light-irradiated surface 13c of the lens 13, the control unit 22 detects a change in capacitance between the electrode portion 14a of the first bus bar 14 and the human body, and switches the light source 20 on and off. The connector portion 23 connects to a connector on the wire harness side that is routed inside the vehicle in which the interior lighting device 1 is installed.

Prisms 11 are optical elements that are located directly above light sources 20 and bend the light emitted from the light sources 20 in any direction. Prisms 11 are integrally molded from insulating, optically transparent synthetic resin or the like.

Figure 3 is a perspective view of the housing 12. Here, if the side facing the lens 13 in the Z direction is the front side of the housing 12, then in Figure 3, the housing 12 is drawn so that the back side, which faces the board 10, is visible. Note that in the following description of the housing 12, in addition to Figure 3, Figures 1, 6, and 7 will be referenced as appropriate.

The housing 12 is a structure disposed opposite the surface of the substrate 10 on which the light source 20 is provided. The housing 12 is also sometimes referred to as an inner cover. The housing 12 is integrally molded from an insulating, light-opaque synthetic resin or the like. The housing 12 has two reflector portions 12a spaced apart from each other to align with the positions of the two light sources 20 on the substrate 10. The two reflector portions 12a are symmetrical to each other, and each has a reflective portion 12b, a support frame portion 12c, and a lens-facing portion 12j.

The reflecting portion 12b is a wall portion that reflects light emitted from the light source 20 and transmitted through the prism 11, and guides the light to the light-transmitting portion 13a of the lens 13. The reflecting portion 12b has, for example, a truncated quadrangular pyramid shape that widens from the first opening to the second opening along the Z direction. In this case, the first opening at the apex of the reflecting portion 12b connects to the light exit portion of the prism 11. Meanwhile, the second opening at the base of the reflecting portion 12b opens toward the light-transmitting portion 13a.

The support frame 12c is a collection of walls surrounding a first space S1, which includes the optical path along which light emitted from the light source 20 passes before reaching the light-transmitting portion 13a of the lens 13. Specifically, the support frame 12c is composed of a combination of two walls roughly parallel to the XZ plane and two walls roughly parallel to the YZ plane. The support frame 12c supports the reflecting portion 12b via the lens-facing portion 12j on the side closest to the light-transmitting portion 13a in the Z direction. Because the two reflector portions 12a in the housing 12 are spaced apart from each other in the X direction, a second space S2 is defined between the two reflector portions 12a. In the second space S2, at least the side of the housing 12 where the bezel 17 is attached is open.

The lens facing portion 12j is located at the top of the housing 12 in the Z direction and is a wall portion parallel to the light-transmitting portion 13a of the lens 13. The shape of the lens facing portion 12j is annular when viewed in the Z direction, and is set to match the shape of the outer periphery of the light-receiving surface 13d of the light-transmitting portion 13a. The surface of the lens facing portion 12j that faces the light-transmitting portion 13a is the lens contact surface 12d, and the surface opposite the lens contact surface 12d is the busbar contact surface 12i. The busbar contact surface 12i is in contact with the first main plane 14c, which is one of the main planes of the electrode portion 14a of the first busbar 14.

The housing 12 also has first protrusions 12g, for example, at multiple locations on the wall that makes up the support frame 12c, which function as a locking mechanism when attaching the lens 13 to the housing 12. The housing 12 also has first protrusions 12f, for example, at multiple locations on the wall that makes up the support frame 12c, which protrude in the Z direction toward the console 16 and function as a locking mechanism when attaching the housing 12 to the console 16. The first protrusions 12f are formed with first engagement holes 12h that engage with second protrusions 16b that are previously provided on the console 16.

The lens 13 is an optical component that transmits at least a portion of the light emitted from the light source 20 and guides it into the vehicle interior. The lens 13 is integrally molded from an insulating, light-transmitting synthetic resin or the like. However, the lens 13 is not limited to a transparent material and may be a so-called translucent material. A lens 13 exists for each reflector portion 12a provided on the housing 12, i.e., for each light source 20. Therefore, in this embodiment, there are two lenses 13, spaced apart to match the positions of the two reflector portions 12a. The two lenses 13 are symmetrical to each other and each has a light-transmitting portion 13a and a busbar contact portion 13b.

The light-transmitting portion 13a is a flat plate-shaped portion that transmits light irradiated from the reflector portion 12a side toward the interior of the vehicle. One of the main planes of the light-transmitting portion 13a is the light-irradiating surface 13c that faces the interior of the vehicle. Because the light-irradiating surface 13c faces the interior of the vehicle, it is both a design surface and a touch surface that the occupant touches with their fingertip F or the like when switching the light on or off. The other main plane of the light-transmitting portion 13a is the light-receiving surface 13d, located opposite the light-irradiating surface 13c, that receives light irradiated from the reflector portion 12a side. The light-transmitting portion 13a also has a frame portion 13e that is continuous with the outer peripheries of the light-irradiating surface 13c and the light-receiving surface 13d.

In this embodiment, the planar shapes of the light irradiation surface 13c and the light receiving surface 13d are approximately rectangular, with two short sides along the X direction and two long sides along the Y direction. Furthermore, when the lens 13 is attached to the housing 12, the outer periphery of the light receiving surface 13d faces the lens contact surface 12d of the housing 12, so the outer periphery of the lens contact surface 12d also becomes approximately rectangular, following the outer periphery of the light receiving surface 13d.

The busbar contact portion 13b is located opposite the board connection portion 14b of the first busbar 14 when the lens 13 is installed in the console 16, and is a structural portion that comes into contact with a portion of the board connection portion 14b. The busbar contact portion 13b has a protruding wall portion 13f and a locking portion 13n (see Figures 6 and 7).

The protruding wall portion 13f is supported by the light-transmitting portion 13a so that one end in the Z direction is continuous with a portion of the frame portion 13e of the light-transmitting portion 13a and protrudes from the light-transmitting portion 13a side toward the substrate 10 along the Z direction. When the lens 13 is attached to the housing 12, the protruding wall portion 13f is located in the second space S2 in the housing 12. The protruding wall portion 13f also supports the locking portion 13n at its other end, which is on the opposite side in the Z direction from the end that is continuous with the frame portion 13e of the light-transmitting portion 13a.

The locking portion 13n is a flat plate parallel to the substrate 10, and by contacting a portion of the substrate connection portion 14b on the surface facing the substrate 10, it locks the portion of the substrate connection portion 14b by pressing it against the substrate 10. To ensure rigidity, the locking portion 13n may be reinforced by a reinforcing plate 13p provided on the side opposite the side facing the substrate 10.

Furthermore, the lens 13 has second protruding pieces 13r that protrude toward the console 16 in the Z direction at multiple locations on the frame portion 13e of the light-transmitting portion 13a and function as a locking mechanism when attaching the lens 13 to the housing 12. The second protruding pieces 13r are formed with second engaging holes 13s that engage with first protrusions 12g that are previously provided on the housing 12.

Figure 4 is a perspective view of the first bus bar 14. In Figure 4, the first bus bar 14 is drawn so that the first main plane 14c of the electrode portion 14a, which contacts the bus bar contact surface 12i of the housing 12, is visible.

The first busbar 14 is a conductive metal member that contacts both the housing 12 and the electrode pads 21 on the substrate 10. The first busbar 14 may be formed by appropriately processing a thin metal plate, such as pressing, cutting, drilling, or bending. A first busbar 14 exists for each reflector portion 12a provided on the housing 12, i.e., for each light source 20. Therefore, in this embodiment, there are two first busbars 14, spaced apart to match the positions of the two reflector portions 12a. The two first busbars 14 are symmetrical to each other, and each has an electrode portion 14a and a substrate connection portion 14b that are integrated with each other.

The electrode portion 14a is a flat plate that is annular as a whole, conforming to the shape of the busbar contact surface 12i of the housing 12. The planar shape of the electrode portion 14a can be set based on the planar shapes of the light-irradiating surface 13c and the light-receiving surface 13d of the light-transmitting portion 13a of the lens 13. In this embodiment, the planar shape of the electrode portion 14a is a rectangular ring formed by a total of four continuous elongated flat plate portions: two first flat plate portions 14j extending in the X direction and two second flat plate portions 14k extending in the Y direction. The outer peripheral shape of the electrode portion 14a is also approximately rectangular, conforming to the outer peripheral shapes of the light-irradiating surface 13c and the light-receiving surface 13d. Therefore, the length in the extension direction of the second flat plate portion 14k is longer than the length in the extension direction of the first flat plate portion 14j.

The electrode portion 14a also has a first main plane 14c, which is one of the main planes, and a second main plane 14d (see Figure 7) which is the other main plane opposite the first main plane 14c. When the first bus bar 14 is installed in the console 16, the first main plane 14c comes into contact with the bus bar contact surface 12i of the housing 12, as described above. When the first bus bar 14 is installed in the console 16, the second main plane 14d comes into contact with a portion of the first holder 15.

Furthermore, the electrode portion 14a has four first biasing portions 14e as multiple biasing portions arranged at intervals along the circumferential direction. Each first biasing portion 14e is provided for each flat plate portion that makes up the electrode portion 14a. Since the four first biasing portions 14e each have the same configuration, the following description will focus on one first biasing portion 14e.

First, in the first biasing portion 14e, a portion of the first flat plate portion 14j or the second flat plate portion 14k is divided in the extension direction of the flat plate portion itself, so that one end, the first end 14f, and the other end, the second end 14g, face each other in the extension direction with a gap between them. In this case, a portion of the flat plate portion on the first end 14f side and a portion of the flat plate portion on the second end 14g side are connected via a connecting portion 14h that is continuous with each other's sides, thereby maintaining the structural continuity of the flat plate portion on which the first biasing portion 14e is provided. From the perspective of making the entire first biasing portion 14e compact or ensuring rigidity, the connecting portion 14h may be an elongated flat plate with a main plane that is approximately perpendicular to the first main plane 14c and the second main plane 14d.

The first biasing portion 14e has two first spring portions 14i. One first spring portion 14i is an elastic piece that is continuous with the first end portion 14f, and the other first spring portion 14i is an elastic piece that is continuous with the second end portion 14g. In other words, the two first spring portions 14i face each other. The free end of each first spring portion 14i is bent from the first main plane 14c side toward the second main plane 14d side. With this structure, the first spring portion 14i can apply a biasing force to a member that comes into contact with it from the side opposite the second main plane 14d.

In this embodiment, the first biasing portion 14e is provided at the middle of the length range of the first flat plate portion 14j or the second flat plate portion 14k in the extension direction. Here, the two first flat plate portions 14j and the two second flat plate portions 14k are the same length, so the two first biasing portions 14e face each other in the X direction or the Y direction. Therefore, the rectangular annular electrode portion 14a as a whole is advantageous in that the multiple first biasing portions 14e can apply a balanced biasing force to the member that contacts it from the side opposite the second main plane 14d. However, depending on the shape of the light-transmitting portion 13a of the lens 13, the shape of the electrode portion 14a is not necessarily limited to a rectangular annular shape. In this case, the position at which the first biasing portion 14e is provided on the electrode portion 14a may be changed as appropriate.

The substrate connection portion 14b is a so-called leg portion, with one portion continuing to the electrode portion 14a and another portion contacting the electrode pad 21 on the substrate 10. The substrate connection portion 14b is a flat plate formed by bending or other processing a long, narrow flat plate, and includes a first base portion 14m, a second base portion 14n, and a contact portion 14p.

The first base portion 14m is a flat plate portion having one end connected to the electrode portion 14a and the other end connected to the second base portion 14n, and supports the second base portion 14n near the electrode pad 21 on the substrate 10. If the electrode portion 14a is maintained in a position along the XY plane, the first base portion 14m may be tilted so that it gradually moves away from the electrode portion 14a in the X direction as it moves away from the electrode portion 14a in the Z direction.

The second base portion 14n is a flat plate portion whose one end is continuous with the first base portion 14m and whose other end is continuous with the contact portion 14p, and is maintained in a position roughly parallel to the substrate 10.

The contact portion 14p is a curved plate portion whose end opposite the side connected to the second base portion 14n is a free end, and is bent so as to convex from the second base portion 14n side toward the substrate 10. Supported by the second base portion 14n in this shape, the contact portion 14p functions as a whole in the same way as a coil spring. A hemispherical indent 14q that directly contacts the electrode pad 21 may be formed at the top of the contact portion 14p. The indent 14q makes point contact with the electrode pad 21 and allows the contact portion 14p to slide on the electrode pad 21 when pressed against it, which can be advantageous for ensuring contact reliability.

Figure 5 is a perspective view of the first holder 15. In Figure 5, the first holder 15 is depicted so that the contact end 15j that contacts the first biasing portion 14e of the first bus bar 14 is visible.

The first holder 15 is a structure that holds the electrode portion 14a of the first bus bar 14 so that it faces the lens-opposing portion 12j of the housing 12. The first holder 15 is integrally molded from an insulating, light-opaque synthetic resin or the like. A first holder 15 exists for each reflector portion 12a provided on the housing 12, i.e., for each light source 20. Therefore, in this embodiment, there are two first holders 15, spaced apart to match the positions of the two reflectors 12a. The two first holders 15 are symmetrical to each other and each is configured as a box or cylinder composed of multiple walls. In this embodiment, the first holder 15 is a box formed by combining four side walls, namely, the first side wall portion 15a, the second side wall portion 15b, the third side wall portion 15c, and the fourth side wall portion 15d, with a bottom wall portion 15e.

The first side wall portion 15a and the second side wall portion 15b are wall portions each having a main plane parallel to the YZ plane and facing each other in the X direction. The Y direction lengths of the first side wall portion 15a and the second side wall portion 15b roughly match the extension direction, i.e., the length in the Y direction, of the second flat plate portion 14k of the electrode portion 14a of the first bus bar 14. On the other hand, the third side wall portion 15c and the fourth side wall portion 15d are wall portions each having a main plane parallel to the XZ plane and facing each other in the Y direction. The lengths of the third side wall portion 15c and the fourth side wall portion 15d roughly match the extension direction, i.e., the length in the X direction, of the first flat plate portion 14j of the electrode portion 14a. The first side wall 15a, third side wall 15c, second side wall 15b, and fourth side wall 15d are arranged continuously in an annular shape on the XY plane, forming a rectangular cylinder whose axial direction is the Z direction and whose cross section is a rectangular annular shape.

Furthermore, in a rectangular cylinder formed by four side walls, including the first side wall 15a, one end in the Z direction is a rectangular annular opening end, which serves as a contact end 15j that comes into contact with a portion of the electrode portion 14a of the first bus bar 14. The contact end 15j is large enough to face the second main plane 14d of the electrode portion 14a, which is also rectangular annular.

The bottom wall 15e has a main plane parallel to the XY plane, and is a wall covering the portion of the rectangular cylinder formed by the first side wall 15a, etc. that is opposite in the Z direction from the side on which the contact end 15j is provided. In other words, the first holder 15, by combining the rectangular cylinder formed by the first side wall 15a, etc. and the bottom wall 15e, becomes a box-like structure with an opening on the inner circumferential region of the contact end 15j and an internal space called the third space S3.

The first holder 15, having this general shape, is disposed within the first space S1 of the reflector portion 12a of the housing 12 and placed on the substrate 10 facing the first space S1 in the Z direction (see Figures 6 and 7). The reflecting portion 12b of the reflector portion 12a is disposed within the third space S3 of the first holder 15. The bottom wall portion 15e also has a through-hole 15f that penetrates between the third space S3 and the space on the side where the substrate 10 is located. The through-hole 15f passes through the prism 11, which is provided on the substrate 10 in alignment with the position of the light source 20. Therefore, the first holder 15 does not obstruct the optical path from the light source 20 to the reflecting portion 12b via the prism 11. Furthermore, the outer surface of the bottom wall portion 15e is provided with multiple support legs 15g, each of whose tips contacts the substrate 10. The first holder 15 may be supported on the substrate 10 by the multiple support legs 15g.

The first holder 15 may also have a guide portion 15h provided on a portion of the outer surface of the first side wall portion 15a, which guides the first base portion 14m of the board connection portion 14b of the first bus bar 14 in its extension direction when the first holder 15 is installed in the console 16. As described above, the first base portion 14m is inclined so as to gradually move away from the electrode portion 14a in the X direction as it moves away from the electrode portion 14a in the Z direction. Therefore, the guide portion 15h has a guide groove 15i that accommodates a portion of the first base portion 14m in accordance with the inclination of the first base portion 14m. Note that the first base portion 14m may or may not be in contact with the guide portion 15h when accommodated in the guide groove 15i.

The console 16 has an opening 16d that opens in the Z direction, and is a housing that houses the substrate 10, prism 11, housing 12, lens 13, first bus bar 14, and first holder 15 through the opening 16d. The interior lighting device 1 is installed inside the vehicle cabin by attaching the console 16 to the interior wall of the vehicle cabin. The console 16 is integrally molded from an insulating, light-opaque synthetic resin or the like.

The console 16 also has a base structure 16a inside that includes a base on which the circuit board 10 is placed, or pins for positioning the circuit board 10 on the base. The console 16 also has second protrusions 16b at multiple locations inside that function as a locking mechanism when the housing 12 is attached to the console 16. The console 16 also has third protrusions 16c at multiple locations on the wall that function as a locking mechanism when the bezel 17 is attached to the console 16.

The bezel 17 is a flat lid attached to the console 16, which houses the various components, so as to cover the storage opening 16d of the console 16. In other words, the bezel 17 is also a design component that faces the interior of the vehicle. The bezel 17 is molded as a single piece from an insulating, light-opaque synthetic resin or the like.

The bezel 17 also has multiple openings 17a that expose the light-emitting surfaces 13c of the lenses 13 toward the interior of the vehicle. In this embodiment, there are two lenses 13, so there are two openings 17a. Furthermore, the bezel 17 has third protruding pieces 17b at multiple locations on the frame edge that protrude toward the console 16 in the Z direction and function as a locking mechanism when attaching the housing 12 to the console 16. The third protruding pieces 17b are formed with third engagement holes 17c that engage with third protrusions 16c that are already provided on the console 16.

Figures 6 and 7 are partial cross-sectional views of the interior lighting device 1. Figure 6 corresponds to the VI-VI cross section in Figure 1, and is a view taken on the XZ plane passing through the entire board connection portion 14b of the first bus bar 14 on the side of one lens 13. Figure 7 corresponds to the VII-VII cross section in Figure 1, and is a view taken on the XZ plane passing through the contact end portion 15j on the third side wall portion 15c of the first holder 15 and the two first spring portions 14i of the first bus bar 14 on the side of one lens 13.

In this embodiment, the first bus bar 14 is positioned within the console 16 so that the first main plane 14c of the electrode portion 14a contacts the bus bar contact surface 12i, which faces the first space S1 in the lens-facing portion 12j of the housing 12. The second main plane 14d of the electrode portion 14a faces the contact end portion 15j of the first holder 15, which is placed on the substrate 10, in the Z direction. The first spring portion 14i, which is part of the first biasing portion 14e provided in advance on the electrode portion 14a, contacts the contact end portion 15j while applying a biasing force to it. Therefore, the first main plane 14c of the electrode portion 14a is pressed against the bus bar contact surface 12i in close contact.

Here, the height dimension in the Z direction for each part of the first holder 15 is preset so that the biasing force of the first spring portion 14i against the contact end portion 15j allows the first main plane 14c to be in close contact with the busbar contact surface 12i. Furthermore, in this embodiment, the first biasing portion 14e is provided for each flat portion, such as the first flat portion 14j of the electrode portion 14a, so that the rectangular annular first main plane 14c can be in close contact with the similarly rectangular annular busbar contact surface 12i without bias.

When the first bus bar 14 is placed in the console 16, the locking portion 13n provided in advance on the bus bar contact portion 13b contacts the second base portion 14n on the board connection portion 14b of the first bus bar 14 near the electrode pad 21 on the board 10, as shown in FIG. 6 . The housing 12 is pre-formed with a through-hole 12e that penetrates between the second space S2 and the back side on which the board 10 is placed. As a result, when the lens 13 is attached to the housing 12, a portion of the board connection portion 14b and a portion of the guide portion 15h of the first holder 15 that guides the board connection portion 14b are exposed from the second space S2 to the board 10. In this state, when the housing 12 with the attached lens 13 is assembled into the console 16, the contact portion 14p on the board connection portion 14b contacts the electrode pad 21 on the board 10. The contact portion 14p is connected to the substrate connection portion 14b in a state where it is bent in advance so that it protrudes from the second base portion 14n side toward the substrate 10 side, and is therefore constantly pressed against the electrode pad 21 by its elastic force.

The lens contact surface 12d of the lens facing portion 12j of the housing 12 is in contact with the light receiving surface 13d of the light transmitting portion 13a of the lens 13. In other words, the first principal plane 14c of the electrode portion 14a and the light receiving surface 13d of the light transmitting portion 13a are adjacent to each other and communicate with each other via the lens facing portion 12j. This results in a capacitive touch switch structure in which the light irradiating surface 13c of the lens 13 serves as a touch surface, and the light is switched on and off when the occupant touches the light irradiating surface 13c.

In this type of capacitive touch switch structure, the light source 20 is initially off and the interior lighting device 1 is turned off, but the control unit 22 continues to monitor the capacitance. From this state, when an occupant in the vehicle touches the light-irradiated surface 13c of the lens 13, the capacitance generated between the occupant's fingertip F and the electrode portion 14a of the first bus bar 14 changes. The control unit 22 then detects the change in capacitance via the board connection portion 14b of the first bus bar 14 and the electrode pad 21, and switches the light source 20 on based on this detection. This causes the interior lighting device 1 to light up.

When the occupant subsequently touches the light-irradiated surface 13c, the capacitance generated between the fingertip F and the electrode portion 14a changes again. As a result, the control unit 22 detects the change in capacitance in the same manner as above and switches the light source 20 off based on this detection. This turns off the interior lighting device 1.

Next, we will explain the effects of the vehicle interior lighting device 1.

The vehicle interior lighting device 1 includes a light source 20 and a lens 13 having a light-transmitting portion 13a that transmits light emitted from the light source 20 toward the vehicle interior. The vehicle interior lighting device 1 includes a housing 12 having an annular lens contact surface 12d that is in surface contact with the outer circumferential shape of the light-receiving surface 13d of the light-transmitting portion 13a, and a busbar contact surface 12i that is the opposite surface of the lens contact surface 12d. The vehicle interior lighting device 1 includes a conductive first busbar 14 having an annular electrode portion 14a that conforms to the shape of the busbar contact surface 12i. The vehicle interior lighting device 1 includes a first holder 15 that has an annular contact end portion 15j that conforms to the shape of the electrode portion 14a and holds the first busbar 14 by bringing the contact end portion 15j into contact with the electrode portion 14a. The vehicle interior lighting device 1 also includes a control unit 22 that switches the light source 20 on and off in response to changes in capacitance between the electrode portion 14a and a part of the human body that touches the light-irradiating surface 13c of the light-transmitting portion 13a. The electrode portion 14a is a flat plate whose first main plane 14c, one of its main planes, is in surface contact with the busbar contact surface 12i, and whose second main plane 14d, the other of its main planes, faces the contact end portion 15j. One of the electrode portion 14a or the contact end portion 15j has a biasing portion that applies a biasing force to the other.

In this vehicle interior lighting device 1, the annular lens contact surface 12d of the housing 12 first comes into surface contact with the light-receiving surface 13d of the light-transmitting portion 13a of the lens 13, following the outer circumferential shape of the light-receiving surface 13d. Additionally, the first main plane 14c of the annular electrode portion 14a of the first busbar 14 comes into surface contact with the busbar contact surface 12i, which is the opposite surface of the housing 12 from the lens contact surface 12d, following the shape of the busbar contact surface 12i. In other words, the light-transmitting portion 13a of the lens 13 and the electrode portion 14a of the first busbar 14 are adjacent to each other through a portion of the housing 12, specifically the lens-facing portion 12j in the above example. Therefore, the vehicle interior lighting device 1 can realize a capacitive touch switch structure in which the light-irradiating surface 13c of the lens 13 functions as a touch surface that can be touched by a part of the human body, such as a fingertip F.

In addition, in the interior lighting device 1, one of the electrode portion 14a or the contact end 15j has a biasing portion that applies a biasing force to the other. In this embodiment, the biasing portion is a plurality of first biasing portions 14e provided on the electrode portion 14a that apply a biasing force to the contact end 15j. When the first biasing portions 14e on the electrode portion 14a apply a biasing force to the contact end 15j, the first main plane 14c of the electrode portion 14a is pressed against the busbar contact surface 12i by a reaction force from the biasing force. Therefore, even if, for example, there is a dimensional error in the housing 12 between different interior lighting device 1 products, the close contact between the housing 12 and the electrode portion 14a is easily maintained. Therefore, in the interior lighting device 1, it is unlikely that the capacitance between the electrode portion 14a and the human body will change sufficiently when a part of the human body touches the light irradiation surface 13c.

As described above, this embodiment provides a vehicle interior lighting device 1 that can stably detect changes in capacitance when switching between on and off.

In addition, in the vehicle interior lighting device 1, the biasing portion may include an elastic piece formed on part of the electrode portion 14a that applies a biasing force to the contact end portion 15j.

In the above example, the first biasing portion 14e includes two first spring portions 14i, each consisting of an elastic piece. These elastic pieces are formed when the entire first bus bar 14 is formed by performing various processes on a thin metal plate. Therefore, this vehicle interior lighting device 1 can be advantageous in that the first biasing portion 14e can be easily provided on the electrode portion 14a.

Furthermore, in the vehicle interior lighting device 1, the first holder 15 may be a box or cylinder having at least a side wall portion, the inside of which defines a third space S3 including the optical path of light. In this case, the contact end 15j may be the tip of the side wall portion.

In the above example, the first holder 15 is a box having four side walls: a first side wall 15a, a second side wall 15b, a third side wall 15c, and a fourth side wall 15d. According to this vehicle interior lighting device 1, the first holder 15 can hold the electrode portion 14a at the contact end 15j without blocking the optical path from the light source 20 to the light-transmitting portion 13a.

Regarding the shape of the box or cylinder serving as the first holder 15, the cross-sectional shape is not limited to the rectangular annular shape exemplified above, but may also be a polygonal annular shape other than a rectangular annular shape or a roughly circular annular shape.

Second Embodiment
In the vehicle interior lighting device 1 according to the second embodiment, a second bus bar 24 exemplified below may be employed instead of the first bus bar 14 in the first embodiment.

Figure 8 is a perspective view of the second bus bar 24 in the second embodiment. Note that the same components of the second bus bar 24 as those of the first bus bar 14 are designated by the same reference numerals, and their description will be omitted.

In the board connection portion 14b of the first bus bar 14, the free end of the contact portion 14p is not generally intended to come into contact with the second base portion 14n. In contrast, in the board connection portion 14b of the second bus bar 24, the free end of the contact portion 14p is a curved end 24a that makes curved contact with the second base portion 14n.

In other words, the vehicle interior lighting device 1 according to the second embodiment includes a substrate 10 on which an electrode pad 21 that is electrically connected to a control unit 22 is mounted. The second bus bar 24 has a substrate connection portion 14b that is a flat plate that is integral with the electrode portion 14a. The substrate connection portion 14b may have a first base portion 14m, a second base portion 14n, and a contact portion 14p. One end of the first base portion 14m is continuous with the electrode portion 14a and extends toward the substrate 10. One end of the second base portion 14n is continuous with the first base portion 14m and is maintained in a position parallel to the substrate 10. One end of the contact portion 14p is continuous with the second base portion 14n and the other end is a free end, and is formed in a convex shape toward the substrate 10 so that a portion of the contact portion 14p comes into contact with the electrode pad 21. In this case, the free end of the contact portion 14p may be a curved end 24a that comes into contact with the second base portion 14n when part of the contact portion 14p comes into contact with the electrode pad 21.

In the vehicle interior lighting device 1 according to the second embodiment, the free end of the contact portion 14p, which functions as a coil spring overall, is curved at the end 24a, preventing excessive displacement of the contact portion 14p. Therefore, the second bus bar 24 can appropriately maintain the contact pressure of the board connection portion 14b against the electrode pad 21.

(Third embodiment)
In the vehicle interior lighting device 1 according to the third embodiment, a third bus bar 34, which will be exemplified below, may be further employed in place of the first bus bar 14 in the first embodiment.

Figure 9 is a perspective view of the third bus bar 34 in the third embodiment. Note that the same components of the third bus bar 34 as those of the first bus bar 14 are designated by the same reference numerals, and their description will be omitted.

In the third bus bar 34, a portion of the first base 14m may have an elastically deformable bent portion 34a. In the example shown in Figure 9, the bent portion 34a is convex on the side opposite the guide portion 15h provided on the first holder 15 so that when the third bus bar 34 is installed in the console 16, it does not come into excessive contact with the guide portion 15h provided on the first holder 15.

In the vehicle interior lighting device 1 according to the third embodiment, the bent portion 34a functions as an elastic portion, allowing deformation of the first base portion 14m, thereby preventing deformation of the electrode portion 14a that is continuous with the first base portion 14m, for example.

(Fourth embodiment)
In the vehicle interior lighting device 1 according to the fourth embodiment, a second holder 25 exemplified below may be employed instead of the first holder 15 in the first embodiment.

Figure 10 is a perspective view of the second holder 25 in the fourth embodiment. Note that the same components of the second holder 25 as those of the first holder 15 are designated by the same reference numerals, and their description will be omitted.

In the second holder 25, the contact end 15j may have an engagement groove 25a cut out in the thickness direction of the side wall portion and into which a portion of the first biasing portion 14e engages. Here, like the first holder 15, the second holder 25 is a box-shaped body having four side walls: the first side wall portion 15a, the second side wall portion 15b, the third side wall portion 15c, and the fourth side wall portion 15d. Therefore, the engagement groove 25a is provided in the contact end 15j for each of the four side walls, aligned with the position of the first spring portion 14i of each first biasing portion 14e.

Figure 11 is a partial cross-sectional view taken along the XZ plane, showing, as an example, the engagement groove 25a provided in the contact end 15j of the third side wall portion 15c and the two first spring portions 14i that engage with the engagement groove 25a.

The two first spring portions 14i shown in Figure 11 face each other in the X direction. The free end of each first spring portion 14i is bent toward the engagement groove 25a. As a result, the two first spring portions 14i each come into contact with a corner 25b of the engagement groove 25a. Since the engagement groove 25a has two corners 25b that face each other in the X direction, one first spring portion 14i comes into contact with one corner 25b, and the other first spring portion 14i comes into contact with the other corner 25b. In other words, the two first spring portions 14i apply biasing forces in opposite directions to their corresponding corners 25b, and therefore engage with one engagement groove 25a in opposing directions, with their positions restricted.

In the vehicle interior lighting device 1 according to the fourth embodiment, the two first spring portions 14i maintain their function of pushing the electrode portion 14a toward the busbar contact surface 12i of the housing 12 and bringing it into close contact. Furthermore, the two first spring portions 14i are positioned in one direction relative to the engagement grooves 25a. In the example of the second holder 25, an engagement groove 25a is provided for each of the four side wall portions, so the first spring portion 14i for each of the four first biasing portions 14e is positioned in either the X direction or the Y direction. Therefore, in a vehicle interior lighting device 1 employing the second holder 25, for example, it is possible to prevent misalignment of the light irradiation surface 13c, which serves as the touch surface, relative to the electrode portion 14a.

Fifth Embodiment
In the vehicle interior lighting device 1 according to the fifth embodiment, the fourth bus bar 44 illustrated below can be adopted instead of the first bus bar 14 in the first embodiment, and the third holder 35 illustrated below can be adopted instead of the first holder 15 in the first embodiment.

Figure 12 is a perspective view of the fourth bus bar 44 in the fifth embodiment. The fourth bus bar 44 has an electrode portion 44a and a board connection portion 44b. The electrode portion 44a is a flat plate body having a ring shape with two continuous first and second flat plate portions 44j and 44k, and a first main plane 44c and a second main plane 44d. The board connection portion 44b has a first base portion 44m, a second base portion 44n, and a contact portion 44p including an indent 44i. Note that each of these portions basically corresponds to each portion of the first bus bar 14.

Here, the fourth bus bar 44 has a second biasing portion 44e instead of the first biasing portion 14e provided on the first bus bar 14. Like the first biasing portion 14e, the second biasing portion 44e includes an elastic piece formed on part of the electrode portion 44a that applies a biasing force to the contact end portion 15j. However, the elastic piece in the second biasing portion 44e is a second spring portion 44g provided in a notch portion 44f formed in part of the first flat plate portion 44j or the second flat plate portion 44k. The second spring portion 44g is a cantilever spring with one end fixed and the other end free along the extension direction of either the first flat plate portion 44j or the second flat plate portion 44k.

Figure 13 is a perspective view of the third holder 35 in the fifth embodiment. Note that the same parts of the third holder 35 as those of the first holder 15 are designated by the same reference numerals, and their description will be omitted.

In the third holder 35, the contact end 15j may have a wide surface 35c with which the second biasing portion 44e comes into contact, and whose dimension in the thickness direction of the side wall is set to be thicker than the thickness of the side wall. Here, like the first holder 15, the third holder 35 is a box-shaped body having four side walls: the first side wall 15a, the second side wall 15b, the third side wall 15c, and the fourth side wall 15d. Therefore, the wide surface 35c is provided on the contact end 15j for each of the four side walls, aligned with the position of the second spring portion 44g of each second biasing portion 44e.

In this case, the wide surface 35c is a surface parallel to the XY plane and may be provided as part of the wide portion 35a. The wide portion 35a is a structural portion that protrudes outward from each side wall portion and has a protruding portion 35b and a reinforcing portion 35d. One surface of the protruding portion 35b forms the wide surface 35c. The reinforcing portion 35d reinforces the protruding portion 35b from the side opposite the wide surface 35c to ensure its rigidity.

Figure 14A is a partial cross-sectional view taken along the XZ plane, showing, as an example, the wide portion 35a provided at the contact end 15j of the third side wall portion 15c and the second spring portion 44g that contacts the wide surface 35c of the wide portion 35a. Figure 14B is a partial cross-sectional view taken along the XZ plane, showing, as an example, the wide portion 35a provided at the contact end 15j of the second side wall portion 15b and the second spring portion 44g that contacts the wide surface 35c of the wide portion 35a.

In the vehicle interior lighting device 1 according to the fifth embodiment, the portion of the fourth bus bar 44 other than the notch 44f where the second spring portion 44g is provided in the second biasing portion 44e remains as a flat plate that is flush with the entire electrode portion 44a. Therefore, the surface area of the first main plane 44c of the electrode portion 44a is greater than the surface area of the first main plane 14c of the electrode portion 14a of the first bus bar 14, improving the accuracy with which the control unit 22 detects changes in capacitance.

On the other hand, with regard to the third holder 35, the wide surface 35c with which the second spring portion 44g comes into contact is set to be thicker than the thickness of the side wall portion other than the portion where the wide portion 35a is provided, thereby preventing the second spring portion 44g from coming off the contact end portion 15j.

Sixth Embodiment
In the vehicle interior lighting device 1 according to the sixth embodiment, a fifth bus bar 54, which will be exemplified below, may be employed instead of the first bus bar 14 in the first embodiment.

Figure 15 is a perspective view of the fifth bus bar 54 in the sixth embodiment. The fifth bus bar 54 has an electrode portion 54a and a board connection portion 54b. The electrode portion 54a is a flat plate body having a ring-shaped configuration with two continuous first and second flat plate portions 54j and 54k, and a first main plane 54c and a second main plane (not shown). The board connection portion 54b has a first base portion 54m, a second base portion 54n, and a contact portion 54p including an indent 54i. Note that each of these portions basically corresponds to each portion of the first bus bar 14.

Here, the fifth bus bar 54 is provided with a third biasing portion 54e instead of the first biasing portion 14e provided on the first bus bar 14. The third biasing portion 54e may be a curved plate portion in which part of the electrode portion 54a is shaped convexly toward the contact end 15j, and which applies a biasing force to the contact end 15j. In other words, the third biasing portion 54e can function as a doubly supported spring portion.

The vehicle interior lighting device 1 according to the sixth embodiment can further increase the reaction force of the biasing force generated by the third biasing portion 54e, thereby preventing a decrease in adhesion between the housing 12 and the electrode portion 54a due to a decrease in the reaction force caused by, for example, vibration or heat.

Seventh Embodiment
In the vehicle interior lighting device 1 according to the seventh embodiment, the sixth bus bar 64 illustrated below can be adopted instead of the first bus bar 14 in the first embodiment, and the fourth holder 45 illustrated below can be adopted instead of the first holder 15 in the first embodiment.

Figure 16 is a perspective view of the sixth bus bar 64 in the seventh embodiment. The sixth bus bar 64 has an electrode portion 64a and a board connection portion 64b. The electrode portion 64a is a flat plate body having a ring shape with two continuous first and second flat plate portions 64j and 64k, and a first main plane 64c and a second main plane 64d. The board connection portion 64b has a first base portion 64m, a second base portion 64n, and a contact portion 64p including an indent 64i. Note that each of these portions basically corresponds to each portion of the first bus bar 14.

Here, the sixth bus bar 64 has a fourth biasing portion 64e instead of the first biasing portion 14e provided on the first bus bar 14. Like the first biasing portion 14e, the fourth biasing portion 64e is formed on part of the electrode portion 64a and includes an elastic piece that applies a biasing force to the contact end portion 15j. However, the elastic piece of the fourth biasing portion 64e is formed by folding back a flat portion protruding from the side of the first flat portion 44j or the second flat portion 44k, and is a third spring portion that can function as a cantilevered helical spring.

Figure 17 is a perspective view of the fourth holder 45 in the seventh embodiment. Note that the same parts of the fourth holder 45 as those of the first holder 15 are designated by the same reference numerals, and their description will be omitted.

In the fourth holder 45, similar to the third holder 35, the contact end 15j may have a wide surface 45c with which the fourth urging portion 64e comes into contact, the dimension of which in the thickness direction of the side wall portion is set thicker than the thickness of the side wall portion. Also, in the fourth holder 45, similar to the second holder 25, the contact end 15j may have an engagement groove 45e that is cut out in the thickness direction of the side wall portion and into which a portion of the fourth urging portion 64e engages. In this case, the wide surface 45c forms the bottom surface of the engagement groove 45e.

Figure 18 is a partial cross-sectional view taken along the XZ plane, showing, as an example, the wide portion 45a provided on the contact end 15j of the first side wall portion 15a and the fourth biasing portion 64e that contacts the wide surface 45c of the wide portion 45a.

In the vehicle interior lighting device 1 according to the seventh embodiment, with respect to the sixth bus bar 64, the fourth biasing portion 64e is an elastic piece that functions as a cantilevered coil spring, so that a coplanar, annular flat plate portion remains over almost the entire electrode portion 44a. Therefore, the surface area of the first main plane 64c of the electrode portion 64a is greater than the surface area of the first main plane 14c of the electrode portion 14a in the first bus bar 14, improving the accuracy with which the control unit 22 detects changes in capacitance.

On the other hand, with regard to the fourth holder 45, the wide surface 45c with which the fourth urging portion 64e comes into contact is set to be thicker than the thickness of the side wall portion other than the portion where the wide portion 45a is provided, thereby preventing the fourth urging portion 64e from coming off the contact end 15j.

Eighth Embodiment
In the vehicle interior lighting device 1 according to the eighth embodiment, the seventh bus bar 74 illustrated below can be adopted instead of the first bus bar 14 in the first embodiment, and the fifth holder 55 illustrated below can be adopted instead of the first holder 15 in the first embodiment.

Figure 19 is a perspective view of the seventh bus bar 74 in the eighth embodiment. The seventh bus bar 74 has an electrode portion 74a and a board connection portion 74b. The electrode portion 74a is a flat plate body having a ring shape with two continuous first and second flat plate portions 74j and 74k, and a first main plane 74c and a second main plane 74d. The board connection portion 74b has a first base portion 74m, a second base portion 74n, and a contact portion 74p including an indent 74i. Note that each of these portions basically corresponds to each portion of the first bus bar 14. Furthermore, in this embodiment, the biasing portion is provided on the fifth holder 55, but not on the seventh bus bar 74.

Figure 20 is a perspective view of the fifth holder 55 in the eighth embodiment. Note that the same parts of the fifth holder 55 as those of the first holder 15 are designated by the same reference numerals, and their description will be omitted.

In this embodiment, the biasing portion is a plurality of fifth biasing portions 55a provided on the contact end portion 15j of the fifth holder 55, which apply a biasing force to the electrode portion 74a. Here, like the first holder 15, the fifth holder 55 is a box having four side walls: a first side wall 15a, a second side wall 15b, a third side wall 15c, and a fourth side wall 15d. Therefore, a fifth biasing portion 55a is provided for each of the four side walls.

In other words, the fifth holder 55 is a box or cylinder having at least a side wall portion, with the inside thereof defining a third space S3 including the optical path of light. The contact end 15j is the tip of the side wall portion. In this case, the fifth biasing portion 55a has a protrusion 55b that protrudes from the tip of the side wall portion toward the electrode portion 74a, and an elongated hole 55c that penetrates the side wall portion in the thickness direction and allows displacement of the protrusion 55b in the direction opposite to the protrusion direction of the protrusion 55b.

Figure 21 is a partial cross-sectional view taken along the XZ plane, showing, as an example, the fifth biasing portion 55a provided on the contact end 15j of the third side wall portion 15c. The height of the protrusion 55b relative to the tip of the side wall portion is preset so that when the protrusion 55b contacts the second main surface 74d of the electrode portion 74a, it is displaced toward the inside of the elongated hole portion 55c as shown in Figure 21. This allows the fifth biasing portion 55a to function as a doubly supported spring, in which the portion of the contact end 15j where the protrusion 55b is provided deforms, and the force generated by the deformation of the contact end 15j becomes the biasing force.

In the vehicle interior lighting device according to the eighth embodiment, the entire first principal plane 74c of the electrode portion 74a contacts the busbar contact surface 12i, allowing the control unit 22 to detect changes in capacitance most efficiently.

The fifth biasing portion 55a can function as a double-arm spring due to the elongated hole portion 55c formed in each side wall portion, but it may also function as a cantilever spring, for example, by having a shape in which part of the elongated hole portion 55c is open from the tip of the side wall portion toward the electrode portion 74a.

Furthermore, in each of the above embodiments, it is assumed that the light-transmitting portion 13a of the lens 13 has a configuration in which substantially the entire light-irradiating surface 13c, which serves as the touch surface, irradiates light into the vehicle interior. However, each embodiment is not limited to this configuration of the light-transmitting portion 13a. For example, the light-transmitting portion 13a may have a transmissive portion consisting only of letters or symbols, and may be configured to block light from surfaces other than the letters or symbols.

The present embodiment has been described above, but it is not limited to this, and various modifications are possible within the scope of the gist of the present embodiment.

REFERENCE SIGNS LIST 1 vehicle interior lighting device 10 substrate 12 housing 12d lens contact surface 12i bus bar contact surface 13 lens 13a light transmitting portion 13c light irradiating surface 13d light receiving surface 14 first bus bar 14a, 44a, 64a, electrode portion 14b substrate connecting portion 14c first main plane 14d second main plane 14e first biasing portion 14i first spring portion 14m first base portion 14n second base portion 14p contact portion 15 first holder 15a first side wall portion 15b second side wall portion 15c third side wall portion 15d fourth side wall portion 15j contact end portion 20 light source 21 electrode pad 22 control portion 24 second bus bar 24a curved end portion 25 second holder 25a, 45e Engagement groove 34 Third bus bar 34a Bent portion 35 Third holder 35c, 45c Wide surface 44 Fourth bus bar 44e Second biasing portion 44g Second spring portion 45 Fourth holder 54 Fifth bus bar 54e Third biasing portion 55 Fifth holder 55a Fifth biasing portion 55b Projection portion 55c Slot portion 64 Sixth bus bar 64e Fourth biasing portion 74 Seventh bus bar S3 Third space

Claims (9)

A light source and
a lens having a light transmitting portion that transmits light emitted from the light source toward the interior of the vehicle;
a housing having an annular lens contact surface that is in surface contact with the outer periphery of the light receiving surface of the light transmitting portion, and a bus bar contact surface that is the opposite surface of the lens contact surface;
a conductive bus bar having an annular electrode portion that conforms to the shape of the bus bar contact surface;
a holder having annular contact ends conforming to the shape of the electrode portions, the holder holding the bus bars by bringing the contact ends into contact with the electrode portions;
a control unit that switches the light source on and off in response to a change in capacitance between the electrode unit and a part of a human body that touches the light irradiation surface of the light transmission unit,
the electrode portion is a flat plate having one main surface in surface contact with the bus bar contact surface and the other main surface facing the contact end portion,
One of the electrode portion and the contact end portion has a biasing portion that applies a biasing force to the other. The vehicle interior lighting device according to claim 1, wherein the biasing portion includes an elastic piece formed on a part of the electrode portion and applying a biasing force to the contact end portion. The vehicle interior lighting device according to claim 1, wherein the biasing portion is a curved plate portion in which a portion of the electrode portion is shaped convexly toward the contact end portion, and which applies a biasing force to the contact end portion. a substrate on which electrode pads that are electrically connected to the control unit are mounted,
the bus bar has a substrate connection portion as a flat plate processed body that is integrated with the electrode portion,
The substrate connection portion is
a first base portion having one end continuous with the electrode portion and extending toward the substrate;
a second base portion having one end continuous with the first base portion and maintained in a position parallel to the substrate;
a contact portion having one end continuous with the second base portion and the other end being a free end, the contact portion being formed in a convex shape toward the substrate so as to come into contact with the electrode pad;
The vehicle interior lighting device according to claim 1 , wherein the free end of the contact portion is a curved end that comes into contact with the second base portion when a part of the contact portion comes into contact with the electrode pad. The vehicle interior lighting device according to claim 4, wherein a portion of the first base portion has an elastically deformable bent portion. the holder is a box or a cylinder having at least a side wall portion, the inside of which is a space including the optical path of the light,
The vehicle interior lighting device according to claim 1 , wherein the contact end portion is a tip end portion of the side wall portion. The vehicle interior lighting device according to claim 6, wherein the contact end portion is notched in the thickness direction of the side wall portion and has an engagement groove into which a portion of the biasing portion engages. The vehicle interior lighting device described in claim 6, wherein the contact end portion has a wide surface with which the biasing portion comes into contact, the dimension in the thickness direction of the side wall portion being set thicker than the thickness of the side wall portion. the holder is a box or a cylinder having at least a side wall portion, the inside of which is a space including the optical path of the light,
the contact end portion is a tip end portion of the side wall portion,
The biasing portion is
a protrusion protruding from the tip of the side wall toward the electrode;
The vehicle interior lighting device according to claim 1 , further comprising: an elongated hole portion that penetrates the side wall portion in a thickness direction and allows displacement of the protrusion portion in a direction opposite to the protruding direction of the protrusion portion.