Lighting unit

Abstract

The present invention provides a lighting unit that reduces the deviation of assembly position that affects the light distribution accuracy at a low cost. The lighting unit (10) is a lighting unit (10) mounted on a vehicle and includes: a light source (14) mounted on a substrate (12); a reflector (16) that reflects light from the light source (14) forward; a projection lens (20) held in a lens holder (18) and disposed in front of the reflector (16); and a light shield (22) for forming a cutoff line (CL) and disposed behind the projection lens (20). The lens holder (18), the reflector (16), and the light shield (22) are configured as a lens holder unit (40) integrally formed therein.

Description

Technical Field

[0001] This invention relates to a lamp unit, and more specifically to a lamp unit for a vehicle headlight. Background Technology

[0002] As such a lighting unit, the structure disclosed in Patent Document 1 is known, which includes: a light source; a projection lens held in a lens holder; a reflector disposed behind the projection lens to reflect light from the light source to the projection lens; and a light-shielding member for blocking a portion of the light from the reflector to form a cut-off line. Conventionally, as in Patent Document 1, these lens holders, reflectors, and light-shielding members are separate components that are assembled as a lighting unit.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2015-173096 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] In recent years, there has been a demand for miniaturization of lighting units. Under such circumstances, as in Patent Document 1, if the lens holder, reflector, and light-shielding component are separate parts, deviations in their construction and assembly positions can sometimes negatively impact light distribution accuracy. This is especially true in the context of miniaturization, where the impact on light distribution accuracy becomes more pronounced.

[0008] The present invention was made in view of the above circumstances, and its object is to provide a luminaire unit that reduces the deviation of assembly position that affects the light distribution accuracy at a low cost.

[0009] means for solving problems

[0010] To achieve the above objectives, one aspect of the present invention relates to a lighting unit mounted on a vehicle, comprising: a light source mounted on a substrate; a reflector reflecting light from the light source forward; a projection lens held in a lens holder and disposed in front of the reflector; and a light-shielding member for forming a cutoff line, disposed behind the projection lens, wherein the lens holder, the reflector, and the light-shielding member are configured as a lens holder unit integrally formed therefrom.

[0011] According to the above method, by integrally molding the reflector, lens bracket, and light shield as a lens bracket unit, the positional accuracy of the light source, reflector, lens, and light shield can be improved by aligning the lens bracket unit with the substrate on which the light source is mounted, thereby reducing light distribution deviations caused by assembly errors. This is also advantageous when the luminaire unit is small. In addition, by integrally molding the reflector, lens bracket, and light shield, the number of parts is reduced, and materials are shared, thereby reducing costs.

[0012] In the above manner, preferably, a substrate mounting portion is formed in the lens support unit.

[0013] In addition, in the above-described manner, preferably, the lens support unit has an opening at a position directly opposite the light-shielding member.

[0014] In addition, in the above-described manner, preferably, the light-shielding member comprises: a horizontal reflective surface that blocks a portion of the light reflected by the reflector to form a light-dark cutoff line; and an inclined reflective surface that tilts forward from the front end of the horizontal reflective surface, forming a secondary reflector in front of the opening of the lens support unit, the secondary reflector reflecting light from the light source toward the inclined reflective surface, and the inclined reflective surface reflecting light incident from the secondary reflector forward.

[0015] In addition, in the above-described manner, preferably, a flange is formed on the back side of the projection lens to abut against the front end face of the lens support unit, a rearwardly protruding positioning protrusion is formed on the back side of the flange, and a recess matching the positioning protrusion is formed on the front end face of the lens support unit.

[0016] Invention Effects

[0017] The luminaire unit involved in the above method can reduce the deviation of the assembly position that affects the light distribution accuracy at a low cost. Attached Figure Description

[0018] Figure 1 This is a front view of a vehicle lamp having the lamp unit according to an embodiment of the present invention.

[0019] Figure 2 It is the edge of the vehicle's lights Figure 1 A sectional view along line II-II.

[0020] Figure 3 This is an exploded perspective view of the aforementioned lighting unit.

[0021] Figure 4 This is a three-dimensional view of the back of the lighting unit.

[0022] Figure 5This is a diagram showing the light distribution pattern of the low beam formed by the aforementioned vehicle lighting fixtures.

[0023] Figure 6 This is a diagram showing the configuration of the mold used for injection molding the lens bracket unit that constitutes the lighting unit.

[0024] Explanation of reference numerals in the attached figures

[0025] 10: Lighting unit;

[0026] 11: Opening;

[0027] 12: Substrate;

[0028] 14: Light source;

[0029] 16: Reflector;

[0030] 16a: First reflecting surface (the reflecting surface of the mirror);

[0031] 17: concave part;

[0032] 18: Lens bracket;

[0033] 19: Substrate mounting section;

[0034] 20: Projection lens;

[0035] 22: Light-shielding components;

[0036] 22d: Reflecting surface;

[0037] 22d: Horizontal reflective surface;

[0038] 22e: Reflective surface;

[0039] 22e: Inclined reflective surface;

[0040] 36: Sub-mirror;

[0041] 36a: Second reflecting surface (reflecting surface of the sub-mirror);

[0042] 40: Lens support unit;

[0043] 44: Open;

[0044] 46: Flange;

[0045] 48: Positioning protrusion;

[0046] 52: concave part;

[0047] 54: protrusion;

[0048] 56: concave part;

[0049] CL: Cutoff line between light and dark. Detailed Implementation

[0050] Hereinafter, the lighting unit 10 according to an embodiment of the present invention will be described with reference to the accompanying drawings. The embodiments are not limited to the invention but are illustrative, and all features and combinations thereof described in the embodiments may not be the essential content of the invention.

[0051] Furthermore, for ease of explanation and illustration, the accompanying drawings are sometimes simplified, except for the essential parts of the invention. Also, in this specification, unless otherwise specified, directions such as front, back, left, and right refer to the directions when viewing the vehicle lamp 1 equipped with the lamp unit 10 from the front. Additionally, in the figures, arrows Up-Lo indicate the vertical direction, Le-Ri indicate the horizontal direction, and Fr-Re indicate the front-back direction.

[0052] (Implementation Method)

[0053] The lamp unit 10 involved in the embodiment is a lamp unit that functions as a vehicle lamp 1 that serves as a low beam headlight mounted at the front of a vehicle.

[0054] Figure 1 This is the front view of vehicle lamp 1. Figure 2 It is the edge of vehicle lighting fixture 1 Figure 1 A sectional view along line II-II. Additionally... Figure 3 This is an exploded perspective view of lighting unit 10. Figure 4 This is an exploded perspective view of the rear of the lens support unit 40 and the projection lens 20 of the lighting unit 10.

[0055] like Figure 1 , Figure 2 As shown, the vehicle lamp 1 includes a lamp unit 10 for low beam, a box-shaped housing 2 with a front opening, and a transparent outer lens 3. The housing 2 is formed of an opaque resin such as polypropylene or polyethylene. The outer lens 3 is formed of a transparent resin such as polycarbonate. The lamp unit 10 is mounted on the front surface of the housing 2 such that the outer lens 3 closes the opening of the housing 2, thereby being disposed within a defined lamp chamber S.

[0056] Between the luminaire unit 10 and the outer lens 3, a shielding extension member (PES cover) 4 is disposed. This shielding extension member (PES cover) 4 has an opening 11 that matches the shape of the projection lens 20 of the luminaire unit 10 (described later), so as to shield the internal structure of the housing 2 from the outside. Figure 1 In the diagram, thick dashed lines represent components that are not visible due to their opaque nature on the front surface. Thin dashed lines represent components that are visible through the projection lens 20, which will be described later.

[0057] The lighting unit 10 includes: a light source 14 mounted on a substrate 12; a reflector 16 disposed above the substrate 12 to reflect light from the light source 14 forward; a projection lens 20 disposed in front of the reflector 16 and held in a lens holder 18; and a light shield 22 for forming a light-dark cutoff line disposed behind the projection lens 20.

[0058] The light source 14 is a white light-emitting diode (LED) with a rectangular emitting surface. The light source 14 is mounted on the substrate 12 with its emitting surface facing upwards. A recess 17 matching the shape of the substrate 12 is formed at the lower part of the reflector 16, and the substrate 12 is positioned between this recess 17 and the rear end of the light-shielding member 22. That is, the substrate mounting portion 19 is defined by the recess 17 formed in the reflector 16 and the rear end of the light-shielding member 22. The substrate 12 is positioned in the substrate mounting portion 19 and, with the emitting surface of the light source 14 facing upwards, is mounted to the base member 24 via the reflector 16 using a screw 21. The base member 24 is configured to also function as a heat sink.

[0059] The base member 24 is mounted to the bracket 26 via a screw 27. The bracket 26 has a rectangular back plate portion 28 that is roughly similar in shape to the vehicle lamp 1 when viewed from the front and extends vertically; and a shelf portion 30 that extends horizontally forward from the back plate portion 28, to which the base member 24 is fixed. Furthermore, a ball joint 32 is mounted on the upper left of the back plate portion 28, and a calibration screw 34 is mounted on both the lower right and lower left. The bracket 26 is mounted to the housing 2 via the ball joint 32 and the calibration screws 34. Thus, the optical axis of the lamp unit 10 can be adjusted in both the vertical and horizontal directions.

[0060] In addition, the rear end of the extension member 4 is attached to the bracket 26, and the lamp unit 10 and the extension member 4 can rotate as a whole.

[0061] Depend on Figure 1 As can be seen, four light sources 14 are arranged at equal intervals in the left-right direction on the substrate 12. Four reflectors 16 are also divided in the left-right direction, corresponding to each of the light sources 14. Each section of the reflector 16 is a rotating elliptical surface arranged such that each light source 14 becomes a first focal point, and a first reflecting surface 16a is formed on its inner surface. The first reflecting surface 16a is formed, for example, by sputtering or vacuum deposition of aluminum or other metals. Four light-shielding members 22 are also arranged side-by-side in the left-right direction. Therefore, the lamp unit 10 consists of four... Figure 2 The shape of the lamp unit with the cross-sectional shape shown is connected in the left-right direction.

[0062] The light-shielding member 22 includes: a horizontal surface 22b, the front end of which is disposed at the second focal point of the reflecting surface 16a of the reflector 16; and an inclined surface 22c, which tilts forward from the front end of the horizontal surface 22b. Reflective surfaces 22d and 22e are formed on the horizontal surface 22b and in the region extending forward from the horizontal surface 22b by vacuum deposition of a metal such as aluminum. Hereinafter, the reflective surface formed on the horizontal surface 22b of the light-shielding member 22 will be referred to as the horizontal reflective surface 22d, and the reflective surface formed on the inclined surface 22c will be referred to as the inclined reflective surface 22e. The front end of the horizontal reflective surface 22d, i.e., the boundary between the horizontal reflective surface 22d and the inclined reflective surface 22e, will be referred to as the ridgeline 22f.

[0063] Figure 5 In the figure, (A) indicates the shape near the ridge 22f of the light-shielding member 22 when viewed from the front. In the figure, line VV represents the vertical reference line, and line HH represents the horizontal reference line. The horizontal surface 22b of the light-shielding member 22 has the following shape: the left side of line VV is higher than line HH, and the right side of line VV is continuously inclined along the two horizontal surfaces of line HH at line VV. This horizontal surface 22b is configured to form as described later. Figure 5 The light distribution pattern of the near beam is shown in (B) in the image.

[0064] The front end of the light-shielding member 22 forms the lower part of the lens support 18 for holding the projection lens 20. The upper part of the lens support 18 is connected to the front end of the sub-reflector 36, which will be described later.

[0065] like Figure 3 As shown, the lens support 18, reflector 16, and light shield 22 are configured as a lens support unit 40, which is integrally formed. Walls 42 are formed at both ends of the lens support unit 40. An opening 44 is formed at the upper part of the lens support unit 40, directly opposite the ridge line 22f of the light shield 22. When the vehicle lamp 1 is illuminated, the opening 44 functions as a heat dissipation vent for dissipating heat from the substrate 12 to the outside of the lens support unit 40. In conventional vehicle lamps, heat dissipation vents are sometimes provided, but they are usually located further forward than the ridge line 22f of the light shield 22. In the lamp unit 10 of this embodiment, since the opening 44 is positioned closer to the substrate 12, which is the heat source, the heat dissipation effect is improved. The inclined surface 22c of the light shield 22 may also have an opening in the portion other than the inclined reflective surface 22e. If an opening is provided, the heat dissipation effect based on the opening 44 is further improved.

[0066] A second reflective surface 36a is formed on the inner surface of the sub-reflector 36, which, as described later, reflects light from the light source 14 toward the inclined reflective surface 22e of the light-shielding member 22. The second reflective surface 36a is formed by deposition of metals such as sputtering or vacuum deposition, similar to the first reflective surface 16a.

[0067] The projection lens 20 is a rectangular projection lens with a primary view, formed of a transparent resin such as polymethyl methacrylate (PMMA). A flange 46 is formed on the outer periphery of the projection lens 20. Furthermore, for ease of drawing, [the following is missing from the original text]. Figure 3 In the text, the projection lens 20 is represented as a main viewing rectangle with a semi-cylindrical shape protruding in front and behind the flange. However, in reality, it is a shape that is cut into a reduced flange shape by cutting the projection lens that protrudes in front and behind, and protrudes from the flange of the main viewing rectangle in front and behind.

[0068] The front end face of the lens support unit 40 forms a lens support 18 that connects to the front end of the light shield 22 and the sub-reflector 36. The lens support 18 has a frame shape of a main view rectangle that matches the flange 46 of the projection lens 20.

[0069] On the back of the flange 46, two positioning protrusions 48 are formed at the upper part of the projection lens 20 and one at the lower part, for a total of three rearward protrusions. The positioning protrusions 48 are formed into a rectangular shape that is the same as the main view shape of the projection lens when in the main view.

[0070] On the other hand, on the front end face of the lens support 18, i.e. the lens support unit 40, at the position corresponding to the positioning protrusion 48 of the flange 46, there are two recesses 52 in the upper part and one in the lower part that match the shape of the positioning protrusion 48.

[0071] Then, the positioning protrusions 48 are fitted into the corresponding recesses 52 for positioning, and the back side of the flange 46 of the projection lens 20 is brought into contact with the front end face of the lens holder 18 (lens holder unit 40) for laser welding, thereby mounting the projection lens 20 onto the lens holder unit 40.

[0072] In conventional luminaires using rectangular projection lenses, positioning protrusions are provided on the lens holder, and recesses of a matching shape are provided on the flange of the projection lens for positioning the projection lens and lens holder. Therefore, when visually inspecting the luminaire from the front surface, the colored positioning protrusions are conspicuous within the flange of the transparent lens, resulting in a poor appearance.

[0073] In the lighting unit 10 of this embodiment, since a positioning protrusion 48 is formed on the back side of the flange 46 of the projection lens 20, the positioning protrusion 48 cannot be directly seen. Furthermore, even if the shape of the positioning protrusion is visible through the flange 46 of the transparent projection lens 20, it is not conspicuous, improving aesthetics. Additionally, in the lighting unit 10 of this embodiment, since the shape of the positioning protrusion 48 is a rectangular shape in the main view, it is less conspicuous compared to other shapes such as circles. Furthermore, by aligning the flange 46 of the projection lens 20, where the positioning protrusion 48 is visible, with the extension member 4, a configuration that is almost invisible from the front can be achieved.

[0074] The number of positioning protrusions 48 is not particularly limited, but it is preferred to have at least three. When the number is three, the structure is the simplest and therefore advantageous.

[0075] In addition, such as Figure 3 , Figure 4 As shown, in addition to the positioning protrusion 48, a protrusion 54 is preferably provided on the back of the flange 46, and a recess 56 matching the protrusion 54 is provided on the front end face of the corresponding lens bracket 18 to prevent misassembly of the lens bracket unit 40 and the projection lens 20 due to slight differences in delivery destination, etc.

[0076] Here, the positioning protrusions 48 and 54 can be made to have different shapes (sizes), but they can also be the same shape. Furthermore, the positional relationship between the positioning protrusions 48 and 54 can be appropriately set. Alternatively, instead of providing protrusions 54 and recesses 56, the positional relationship between multiple positioning protrusions 48 and recesses 52 can be changed to serve as a mechanism to prevent misassembly.

[0077] In the lighting unit 10 of this embodiment, the reflector 16, lens bracket 18, and light shield 22 are integrally formed as a lens bracket unit 40. Therefore, by simply aligning the lens bracket unit 40 with the substrate 12 on which the light source 14 is mounted, the positional accuracy of the light source 14, reflector 16, projection lens 20, and light shield 22 can be improved, reducing light distribution deviations caused by assembly errors. In particular, when miniaturizing the lighting unit 10, the impact of assembly errors in the constituent components becomes relatively large; however, if the lens bracket unit 40 is integrally formed as in this embodiment, such assembly deviations between components are avoided. Furthermore, by integrally forming the reflector 16, lens bracket 18, and light shield 22 (single-color forming), the number of components is reduced, allowing for material sharing and thus cost reduction.

[0078] At this time, the substrate 12 equipped with the light source 14 can be configured, for example, to be fixed to the base member 24, or it can be configured to have the lens support unit 40 mounted relative to the base member 24. However, as in the above embodiment, if a substrate mounting portion 19 for positioning and holding the substrate 12 equipped with the direct light source 14 is formed on the lens support unit 40, the positional accuracy of the light source 14, the reflector 16, the lens support 18, and the light shield 22 is improved, which is particularly advantageous.

[0079] Next, refer to Figure 2 as well as Figure 5 Section (A) describes the function of the vehicle lamp 1 equipped with lamp unit 10.

[0080] The light emitted from the light source 14 is reflected by the first reflecting surface 16a of the reflector 16 and converges near the edge 22f of the light-shielding member 22. The light converged near the edge 22f is reversed vertically and horizontally by the projection lens 20 and then shines as parallel light L1 in front of the lamp. In the light distribution pattern formed at this time, dark areas are formed due to the light-shielding member 22.

[0081] Figure 5 (B) is a schematic diagram showing the light distribution pattern of the low beam formed by vehicle lamp 1 projected onto an imaginary screen positioned in front of the lamp. Figure 5 As shown in (B), the vehicle lamp 1 forms a light distribution pattern of a low beam with a cut-off line CL on its upper surface. This cut-off line CL is formed to prevent glare from oncoming vehicles. Therefore, the position of the cut-off line, i.e., the shape of the ridge of the shading element, is designed according to whether right-hand or left-hand traffic is used. The vehicle lamp 1 is a right-hand traffic lamp.

[0082] A portion of the light emitted from the light source 14 is reflected by the reflective surface of the secondary reflector, and then further reflected by the inclined reflective surface of the light-shielding member 22, becoming parallel light that enters the projection lens 20 to form the elevated sign illumination light L2. An elevated sign refers to a road sign or similar marker located above the front of a vehicle and passing overhead as the vehicle moves.

[0083] Next, the mold used to form the lens bracket unit 40 of the lamp unit 10 according to the embodiment will be described. The lens bracket unit 40 is formed by one-piece molding based on opaque resin such as polyethylene or polypropylene.

[0084] Figure 6This is a cross-sectional view of the mold 200 used for injection molding the lens bracket unit 40 of the lamp unit 10 according to the embodiment. The mold 200 includes a cavity-side mold 210, a core-side mold 220, and a sliding mold 230. A cavity C1 is formed on the dividing surface PL of the cavity-side mold 210 and the core-side mold 220, which divides the portion of the reflector 16 having the substrate mounting portion 19.

[0085] Additionally, the cavity-side mold 210 protrudes relative to the core-side mold 220 at the portion corresponding to the opening 44 of the lens support unit 40, and cooperates with the core-side mold 220 and the sliding mold 230 to form the lower part of the lens support 18 and the cavity C2 of the dividing light-shielding member 22. The cavity-side mold 210 defines a portion of the inclined reflective surface 22e within the horizontal surface 22b and inclined surface 22c of the light-shielding member 22, while the sliding mold 230 defines the portion of the lens support 18 and the portion of the inclined reflective surface 22e within the inclined surface 22c of the light-shielding member 22, excluding the inclined reflective surface 22e.

[0086] In addition, the cavity side mold 210 and the sliding mold 230 cooperate to form the cavity C3 that divides the sub-reflector 36 and the upper part of the lens support 18.

[0087] Here, in the lens support unit 40, the rear end 22a of the horizontal surface 22b of the light-shielding member 22 is designed to be located further forward than the front end of the reflector 16 in the front-rear cross-section. Furthermore, the front end of the inclined reflective surface 22e in the inclined surface 22c of the light-shielding member 22 is designed to be located further rearward than the rear end of the sub-reflector 36. Additionally, the inclination of the inclined surface 22c of the light-shielding member 22 relative to the horizontal line is designed to be greater than the inclination of the reflective surface 36a of the sub-reflector 36 relative to the horizontal line.

[0088] By designing the lens support unit 40 in this way, and by opening the cavity-side mold 210, the core-side mold 220, and the sliding mold 230 in the directions of arrows A1, A2, and A3 respectively, the undercut can be avoided, and the lens support unit 40, as a molded product, can be demolded.

[0089] In a luminaire unit for low beam applications, a light-shielding element is required for forming the cutoff line CL. If a light-shielding element is included, and the lens support, reflector, and light-shielding element are integrally formed into a lens support unit, the light-shielding element may become a dead angle, preventing the mold from being properly formed. In the luminaire unit 10 of this embodiment, since an opening 44 is provided at the upper part of the lens support unit 40 opposite to the light-shielding element 22, the opening 44 can be used to divide the reflective surface 22d and reflective surface 22e of the light-shielding element in the cavity-side mold 210, the core-side mold 220, and the sliding mold 230, thereby enabling integral forming.

[0090] When the lens bracket, reflector, and light shield are integrally formed, it is not necessarily necessary to have an opening on the upper surface opposite to the light shield. However, as in the lighting unit 10 of the embodiment, in a structure that includes a sub-reflector 36 and a light shield 22 having a horizontal surface 22b and an inclined reflective surface 22e, and illuminates the overhead sign, if integrally formed, the horizontal surface 22b and the inclined surface 22c would inevitably become dead angles. If, as in this embodiment, an opening 44 is provided on the upper surface opposite to the light shield 22 (reflective surfaces 22d and 22e), then even in a structure that illuminates the overhead sign, the reflector 16, the light shield 22, and the lens bracket 18 can be integrally formed.

Claims

1. A lighting unit mounted on a vehicle, characterized in that, The lighting unit includes: The light source is mounted on the substrate; A reflector that reflects light from the light source forward; A projection lens, held in a lens holder, is positioned in front of the reflector; as well as A light-shielding element for forming the cutoff line is disposed behind the projection lens. The lens holder, the reflector, and the light-shielding member constitute a lens holder unit formed by integrally molding them together. The lens support unit has an opening at a position directly opposite the light-shielding member. The light-shielding component includes: A horizontal reflective surface that blocks a portion of the light reflected by the reflector, thus forming a cutoff line between light and dark; and The inclined reflective surface tilts forward from the front end of the horizontal reflective surface. A secondary reflector is formed in front of the opening of the lens support unit, and the secondary reflector reflects light from the light source toward the inclined reflective surface. The tilted reflective surface will reflect the light incident from the sub-reflector forward.

2. The lighting unit according to claim 1, characterized in that, A substrate mounting portion is formed on the lens support unit.

3. The lighting unit according to claim 1 or 2, characterized in that, On the outer periphery of the projection lens, a flange is formed on its back side to abut against the front end face of the lens support unit. A rearwardly protruding positioning protrusion is formed on the back side of the flange, and a recess matching the positioning protrusion is formed on the front end face of the lens support unit.

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