Illumination device for vehicle and lamp for vehicle

Abstract

The invention provides a vehicle lighting device and a vehicle lamp, which can change the total luminous flux reduction proportion in a high ambient temperature area of a light-emitting element. A vehicle lighting device according to an embodiment includes: a socket; the substrate is arranged on one end part side of the lamp holder; the light-emitting element is arranged on the substrate; a control element provided on the substrate and having a current driver and a current setting circuit, the output side of the current driver being electrically connected to the light emitting element, and the output side of the current setting circuit being electrically connected to the current driver; a first circuit which is provided on the substrate, is electrically connected to the first input side of the current setting circuit, and has a resistance value that changes in accordance with the ambient temperature of the light-emitting element; and a second circuit which is provided on the substrate, is electrically connected to the second input side of the current setting circuit, and has a resistance value that changes in accordance with the ambient temperature of the light-emitting element. The amount or proportion of the output current flowing to the light-emitting element is changed in accordance with the ambient temperature of the light-emitting element.

Description

Technical Field

[0001] The present invention relates to a vehicle lighting device and a vehicle lamp. Background Art

[0002] In view of energy saving and long life, vehicle lighting devices including light emitting elements such as light emitting diodes are becoming popular instead of vehicle lighting devices including lamps having filaments. Vehicle lighting devices including light emitting elements include, for example, a substrate on which the light emitting elements and circuit elements are mounted.

[0003] Here, when current flows through the light-emitting element, light is radiated from the light-emitting element, and heat is generated in the light-emitting element and the circuit element. In addition, in the case of a vehicle lighting device, the temperature of the environment in which the vehicle lighting device is installed is sometimes around 85°C. Therefore, there is a concern that the temperature of the light-emitting element becomes too high and exceeds the maximum junction temperature. If the temperature of the light-emitting element exceeds the maximum junction temperature, there is a concern that the light-emitting element fails or the function of the light-emitting element is reduced.

[0004] Therefore, a vehicle lighting device is proposed, which includes a control element that controls a current flowing in a light emitting element according to the ambient temperature of the light emitting element. In other words, a vehicle lighting device is proposed that includes a control element that performs temperature derating. This control element reduces the total luminous flux of light irradiated from the light emitting element based on the ambient temperature of the light emitting element in an area where the ambient temperature of the light emitting element is high.

[0005] However, depending on the type or application of the vehicle lighting device, the total luminous flux at a predetermined temperature may differ from the total luminous flux specified by the temperature derating.

[0006] Therefore, it is desired to develop a technology that can change the ratio of reduction of the total luminous flux in a region where the ambient temperature of a light emitting element is high.

[0007] [Prior art literature]

[0008] [Patent Document]

[0009] [Patent Document 1] Japanese Patent No. 7018124 Summary of the invention

[0010] [Problems to be solved by the invention]

[0011] An object of the present invention is to provide a vehicle lighting device and a vehicle lamp that can change the ratio of total luminous flux reduction in a region where the ambient temperature of a light emitting element is high.

[0012] [Technical means to solve the problem]

[0013] A vehicle lighting device according to an embodiment includes: a lamp holder; a substrate provided on one end side of the lamp holder; a light emitting element provided on the substrate; a control element provided on the substrate and having a current driver and a current setting circuit, wherein an output side of the current driver is electrically connected to the light emitting element, and an output side of the current setting circuit is electrically connected to the current driver; a first circuit provided on the substrate and electrically connected to a first input side of the current setting circuit, and having a resistance value that changes according to an ambient temperature of the light emitting element; and a second circuit provided on the substrate and electrically connected to a second input side of the current setting circuit, and having a resistance value that changes according to the ambient temperature of the light emitting element. The current setting circuit reduces an output current flowing to the light emitting element as the ambient temperature of the light emitting element increases based on a change in the resistance value of the first circuit in a temperature range where the ambient temperature of the light emitting element exceeds a first temperature and is not more than a second temperature higher than the first temperature. The current setting circuit increases the ratio of reducing the output current flowing to the light emitting element as the ambient temperature of the light emitting element rises based on the change in the resistance value of the second circuit in a temperature region where the ambient temperature of the light emitting element exceeds the second temperature.

[0014] [Effects of the Invention]

[0015] According to the embodiment of the present invention, there can be provided a vehicle lighting device and a vehicle lamp capable of changing the ratio of reduction of the total luminous flux in a region where the ambient temperature of a light emitting element is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic perspective view for illustrating the vehicle lighting device according to the present embodiment.

[0017] Figure 2 yes Figure 1 AA line cross-sectional view of the vehicle lighting device in FIG.

[0018] Figure 3 is a circuit diagram for illustrating a light emitting circuit.

[0019] Figure 4 is a circuit diagram for illustrating a light emitting circuit of a comparative example.

[0020] Figure 5 This is a graph for illustrating the effects of the light emitting circuit of the comparative example.

[0021] Figure 6 This is a graph for illustrating the effects of the light emitting circuit of the comparative example.

[0022] Figure 7 This is a graph for illustrating the effects of the light emitting circuit of this embodiment.

[0023] Figure 8 This is a graph for illustrating another effect of the light emitting circuit of the comparative example.

[0024] Fig. 9 is a circuit diagram for illustrating a light emitting circuit according to another embodiment.

[0025] Fig.10 This is a graph for illustrating the effects of the light emitting circuit.

[0026] Fig.11 is a circuit diagram for illustrating a light emitting circuit according to another embodiment.

[0027] Fig.12 is a circuit diagram for illustrating a light emitting circuit according to another embodiment.

[0028] Fig.13 is a circuit diagram for illustrating a light emitting circuit according to another embodiment.

[0029] Fig.14 is a circuit diagram for illustrating a light emitting circuit according to another embodiment.

[0030] Fig.15 It is a schematic partial cross-sectional view for illustrating a vehicle lamp.

[0031] [Explanation of Symbols]

[0032] 1: Vehicle lighting devices

[0033] 10: Lamp holder

[0034] 11: Installation Department

[0035] 20: Light emitting module

[0036] 21: Substrate

[0037] 20a~20f: Light-emitting circuit

[0038] 22: Light-emitting components

[0039] 25: Circuit components

[0040] 25a: Resistor

[0041] 25b: Protection element

[0042] 25c: Control elements

[0043] 25c1: Current driver

[0044] 25c2: Current setting circuit

[0045] 25c3: Constant current circuit

[0046] 25d: Negative characteristic thermistor

[0047] 25e: Resistance

[0048] 25f: Positive characteristic thermistor

[0049] 25g: Negative characteristic thermistor

[0050] 25h: Positive characteristic thermistor

[0051] 100: Vehicle lighting

[0052] 101: Frame

[0053] Ia: Output current DETAILED DESCRIPTION

[0054] Hereinafter, the embodiments will be described with reference to the drawings. In addition, in each of the drawings, the same components are denoted by the same reference numerals and detailed descriptions thereof are appropriately omitted.

[0055] (Vehicle lighting device)

[0056] The vehicle lighting device 1 of the present embodiment can be provided in, for example, a car or a train. As the vehicle lighting device 1 provided in the car, for example, it can be used in a front combination light (for example, a combination of a daytime running lamp (DRL), a position lamp, a turn signal lamp, etc.) or a rear combination light (for example, a combination of a stop lamp, a tail lamp, a turn signal lamp, a back lamp, a fog lamp, etc.). However, the use of the vehicle lighting device 1 is not limited to these.

[0057] Figure 1 It is a schematic perspective view for illustrating the vehicle lighting device 1 according to the present embodiment.

[0058] Figure 2 yes Figure 1 AA line cross-sectional view of the vehicle lighting device 1 in FIG.

[0059] like Figure 1 and Figure 2 As shown, in the vehicle lighting device 1 , for example, a lamp holder 10 , a light emitting module 20 , a power supply unit 30 , and a heat transfer unit 40 are provided.

[0060] The lamp holder 10 includes, for example, a mounting portion 11 , a bayonet 12 , a flange 13 , heat dissipation fins 14 , and a connector holder 15 .

[0061] The mounting portion 11 is provided on the surface of the flange 13 on the side opposite to the side on which the heat dissipation fins 14 are provided. The outer shape of the mounting portion 11 can be set to a columnar shape. The outer shape of the mounting portion 11 is, for example, a cylindrical shape. The mounting portion 11 has, for example, a recessed portion 11a opened at the end on the side opposite to the flange 13 side.

[0062] The bayonet 12 is provided, for example, on the side surface of the mounting portion 11. The bayonet 12 protrudes toward the outside of the vehicle lighting device 1. The bayonet 12 faces the flange 13. A plurality of bayonet 12 may be provided. The bayonet 12 is used, for example, when the vehicle lighting device 1 is mounted on a frame 101 of a vehicle lamp 100 described later. The bayonet 12 can be used for a twist lock.

[0063] The flange 13 is plate-shaped. For example, the flange 13 is substantially disk-shaped. The side surface of the flange 13 is located outside the vehicle lighting device 1 compared to the side surface of the bayonet 12 .

[0064] The heat dissipation fin 14 is disposed on the side of the flange 13 opposite to the mounting portion 11. At least one heat dissipation fin 14 may be provided. Figure 1 As shown, a plurality of heat dissipation fins 14 may be provided on the lamp holder 10. The plurality of heat dissipation fins 14 may be arranged side by side in a predetermined direction. The heat dissipation fins 14 may be, for example, plate-shaped or cylindrical.

[0065] The connector bracket 15 is provided on the side of the flange 13 opposite to the mounting portion 11. The connector bracket 15 can be provided in parallel with the heat dissipation fins 14. The connector bracket 15 is cylindrical, and a connector 105 having a sealing member 105a is inserted inside.

[0066] The lamp holder 10 has the function of holding the light emitting module 20 and the power supply unit 30 and the function of transferring the heat generated in the light emitting module 20 to the outside. Therefore, the lamp holder 10 is preferably formed of a material with high thermal conductivity. For example, the lamp holder 10 can be formed of a metal such as aluminum alloy.

[0067] In addition, the lamp holder 10 may be formed of, for example, a highly thermally conductive resin. A highly thermally conductive resin is, for example, a resin obtained by mixing a filler such as carbon or aluminum oxide with a resin such as polyethylene terephthalate (PET) or nylon. If the lamp holder 10 includes a highly thermally conductive resin, the heat generated in the light emitting module 20 can be efficiently dissipated. In addition, the weight of the lamp holder 10 can be reduced.

[0068] The power supply portion 30 includes, for example, a plurality of power supply terminals 31 and a holding portion 32 .

[0069] The multiple power supply terminals 31 can be set as rod-shaped bodies. One end of the multiple power supply terminals 31 protrudes from the bottom surface 11a1 of the recessed portion 11a. One end of the multiple power supply terminals 31 is welded to the wiring pattern 21a provided on the substrate 21. The other end of the multiple power supply terminals 31 is exposed to the inside of the hole of the connector bracket 15. The connector 105 is engaged with the multiple power supply terminals 31 exposed to the inside of the hole of the connector bracket 15. The multiple power supply terminals 31 are formed of metal such as copper alloy. In addition, the shape, configuration, material, etc. of the multiple power supply terminals 31 are not limited to the examples and can be appropriately changed.

[0070] The lamp holder 10 is, for example, formed of a highly thermally conductive resin containing a filler using carbon, or a metal, and thus becomes a lamp holder 10 having electrical conductivity. Therefore, the holding portion 32 is provided to insulate the plurality of power supply terminals 31 from the electrically conductive lamp holder 10. In addition, when the lamp holder 10 is formed of a highly thermally conductive resin having insulation properties (for example, a highly thermally conductive resin containing a filler using alumina), the holding portion 32 may be omitted. The holding portion 32 may be, for example, pressed into a hole provided in the lamp holder 10, or bonded to the inner wall of the hole.

[0071] The heat transfer portion 40 is disposed between the lamp holder 10 and the light emitting module 20 (substrate 21). Figure 1 ,and Figure 2 As shown, the heat transfer portion 40 is, for example, provided inside the recess 11b opened at the bottom surface 11a1 of the recess 11a. For example, the heat transfer portion 40 may be bonded to the inner wall of the recess 11b, or assembled inside the recess 11b via thermal grease (heat dissipation grease), or embedded inside the recess 11b using an insert molding method. The heat transfer portion 40 is formed of a material having a high thermal conductivity. For example, the heat transfer portion 40 may be formed of a metal such as aluminum, aluminum alloy, copper, or copper alloy. In addition, when the lamp holder 10 is formed of metal, or when less heat is generated in the light emitting module 20, the heat transfer portion 40 may be omitted.

[0072] The light emitting module 20 includes, for example, a substrate 21 , a light emitting element 22 , a frame portion 23 , a sealing portion 24 , and a circuit element 25 .

[0073] The substrate 21 is provided on one end side of the lamp holder 10. The substrate 21 may be bonded to the heat transfer portion 40, for example. In this case, the adhesive is preferably an adhesive with high thermal conductivity. For example, the adhesive may be an adhesive mixed with a filler of a conductive material or an inorganic material.

[0074] The substrate 21 is plate-shaped. The planar shape of the substrate 21 (the shape when viewed from the direction along the central axis 1a of the vehicle lighting device 1) is, for example, a substantially quadrilateral. The substrate 21 can be formed of, for example, inorganic materials such as ceramics (such as alumina or aluminum nitride), organic materials such as phenolic paper or epoxy glass, etc. In addition, the substrate 21 can also be a metal core substrate formed by coating the surface of a metal plate with an insulating material. In addition, the substrate 21 can have a single-layer structure or a multi-layer structure.

[0075] Moreover, the wiring pattern 21a is provided on the surface of the substrate 21. The wiring pattern 21a is formed of, for example, a material containing silver as a main component or a material containing copper as a main component.

[0076] The light emitting element 22 is provided on the substrate 21 (the surface of the substrate 21 opposite to the lamp holder 10). The light emitting element 22 is electrically connected to the wiring pattern 21a. At least one light emitting element 22 may be provided. Figure 1 and Figure 2 In the illustrated vehicle lighting device 1 (light emitting module 20), a plurality of light emitting elements 22 are provided. When a plurality of light emitting elements 22 are provided, the plurality of light emitting elements 22 may be connected in series.

[0077] The light emitting element 22 may be, for example, a light emitting diode, an organic light emitting diode, a laser diode, or the like.

[0078] The light emitting element 22 may be a chip-shaped light emitting element, a surface mounted light emitting element such as a plastic leaded chip carrier (PLCC) type light emitting element with leads, or a cannonball type light emitting element with leads. Figure 2 The light emitting element 22 illustrated in the example is a chip-shaped light emitting element. In this case, if the miniaturization of the light emitting module 20 and the miniaturization of the vehicle lighting device 1 are taken into consideration, it is preferably a chip-shaped light emitting element. The following is an example in which the light emitting element 22 is a chip-shaped light emitting element.

[0079] The chip-shaped light emitting element 22 can be mounted on the wiring pattern 21a by chip on board (COB). The chip-shaped light emitting element 22 can be any of an upper electrode type light emitting element, a top and bottom electrode type light emitting element, and a flip chip type light emitting element.

[0080] The frame 23 is provided on the substrate 21. The frame 23 is bonded to the substrate 21. The frame 23 is frame-shaped and surrounds the light emitting element 22. The frame 23 is formed of, for example, a thermoplastic resin. The frame 23 may have a function of defining a formation range of the sealing portion 24 and a function as a reflector. In addition, the frame 23 may be omitted. In the case where the frame 23 is omitted, for example, a dome-shaped sealing portion 24 is provided on the substrate 21.

[0081] The sealing part 24 is provided inside the frame part 23. The sealing part 24 is provided so as to cover the region surrounded by the frame part 23. The sealing part 24 is provided so as to cover the light emitting element 22. The sealing part 24 includes a resin having light transmittance. The resin is, for example, a silicone resin. In addition, the sealing part 24 may also include a fluorescent substance.

[0082] Furthermore, optical components may be provided as needed. Examples of the optical components include convex lenses, concave lenses, light guides, etc. The optical components may be provided on the sealing portion 24, for example.

[0083] The circuit element 25 can be a passive element or an active element for constituting the light emitting circuit 20a having the light emitting element 22. The circuit element 25 is provided on the substrate 21. The circuit element 25 is provided, for example, around the frame 23 and electrically connected to the wiring pattern 21a. The circuit element 25 is electrically connected to the light emitting element 22 via the wiring pattern 21a.

[0084] Figure 3 2 is a circuit diagram for illustrating the light emitting circuit 20 a.

[0085] like Figure 3 As shown, the light emitting circuit 20a includes, for example, a light emitting element 22 and a circuit element 25. The circuit element 25 may be, for example, a resistor 25a, a protection element 25b, a control element 25c, a negative characteristic thermistor 25d (equivalent to an example of a first negative characteristic thermistor), a resistor 25e, and a positive characteristic thermistor 25f (equivalent to an example of a second positive characteristic thermistor). The circuit element 25 provided in the light emitting circuit 20a is not limited to the illustrated one. For example, in addition to the above-mentioned elements, the light emitting circuit 20a may also include a capacitor, an inductor, a surge absorber, a varistor, an integrated circuit, an operation element, and the like.

[0086] like Figure 1 and Figure 2 As shown, the resistor 25a can be, for example, a surface mount resistor, a resistor with leads (metal oxide film resistor), a film resistor formed by screen printing or the like. Figure 1 The resistor 25 a shown as an example is a surface mount resistor.

[0087] Here, the forward voltage characteristic of the light emitting element 22 has a deviation, so if the applied voltage between the anode terminal and the ground terminal is set to be fixed, the brightness (luminous flux, brightness, luminosity, illuminance) of the light emitted from the light emitting element 22 will have a deviation. Therefore, the value of the current flowing in the light emitting element 22 is made within a prescribed range by the resistor 25a connected in series with the light emitting element 22, so that the brightness of the light emitted from the light emitting element 22 is within a prescribed range. In this case, by changing the resistance value of the resistor 25a, the value of the current flowing in the light emitting element 22 is made within a prescribed range.

[0088] In the case where the resistor 25a is a surface mounted resistor or a resistor with leads, etc., the resistor 25a having an appropriate resistance value is selected according to the forward voltage characteristics of the light emitting element 22. In the case where the resistor 25a is a film resistor, the resistance value can be increased by removing a portion of the resistor 25a. For example, a portion of the film resistor can be easily removed by irradiating the film resistor with laser light. In addition, the number, arrangement, size, etc. of the resistor 25a are not limited to the examples, and can be appropriately changed according to the number, specifications, etc. of the light emitting element 22.

[0089] The protection element 25b is provided, for example, to prevent a reverse voltage from being applied to the light emitting element 22 and to prevent a pulse noise from being applied from the reverse direction to the light emitting element 22. The protection element 25b is, for example, a diode. Figure 1 The protection element 25b shown as an example is a surface-mount diode.

[0090] The control element 25c controls the current (output current Ia) flowing to the light emitting element 22 according to the ambient temperature of the light emitting element 22. For example, the control element 25c may be an integrated circuit capable of performing temperature derating.

[0091] like Figure 3 As shown, the control element 25c has a VIN terminal, an OUT terminal, an RTH terminal (equivalent to an example of the first input side), an ISET terminal (equivalent to an example of the second input side), and a GND terminal. The VIN terminal is electrically connected to a battery mounted on the vehicle, for example, via the protection element 25b. The OUT terminal is electrically connected to the light-emitting element 22, for example, via the resistor 25a. In this case, the anode of the light-emitting element 22 is electrically connected to the OUT terminal. The cathode of the light-emitting element 22 is electrically connected to the ground terminal of the vehicle, such as the chassis of the vehicle body. The ISET terminal is electrically connected to, for example, a resistor 25e and a positive characteristic thermistor 25f (equivalent to an example of the second circuit) connected in series. The RTH terminal is electrically connected to a negative characteristic thermistor 25d (equivalent to an example of the first circuit). The GND terminal is electrically connected to the ground terminal of the vehicle, for example.

[0092] In addition, the control element 25c includes, for example, a current driver 25c1, a current setting circuit 25c2, and a constant current circuit 25c3.

[0093] The input side of the current driver 25c1 is electrically connected to the VIN terminal. The output side of the current driver 25c1 is electrically connected to the light emitting element 22 via the OUT terminal. The current driver 25c1 generates a current (output current Ia) flowing to the light emitting element 22. The current driver 25c1 performs constant current control on the output current Ia so that the output current Ia becomes a specified value. The current driver 25c1 has, for example, a constant current circuit including an output transistor, a sense resistor, an error amplifier, etc. In addition, the target value of the output current Ia is set based on the set current Ib from the current setting circuit 25c2.

[0094] One input side of the current setting circuit 25c2 is electrically connected to the negative characteristic thermistor 25d via the RTH terminal. The other input side of the current setting circuit 25c2 is electrically connected to the resistor 25e and the positive characteristic thermistor 25f via the ISET terminal. The output side of the current setting circuit 25c2 is electrically connected to the current driver 25c1. The current setting circuit 25c2 generates a setting current Ib for setting a target value of the output current Ia. The setting current Ib is generated based on a change in the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal. If the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases, the current setting circuit 25c2 makes an adjustment to reduce the output current Ia.

[0095] The current setting circuit 25c2 adjusts the set current Ib based on the terminal voltage generated at the ISET terminal. If the combined resistance value of the resistor 25e and the positive characteristic thermistor 25f electrically connected to the ISET terminal increases, the current setting circuit 25c2 adjusts the output current Ia to increase the ratio of reduction.

[0096] The constant current circuit 25c3 is electrically connected between the input side of the current setting circuit 25c2 and the RTH terminal. The constant current circuit 25c3 allows a current of a predetermined value to flow through the negative characteristic thermistor 25d via the RTH terminal. Therefore, a terminal voltage based on the change in the resistance value of the negative characteristic thermistor 25d is generated at the RTH terminal.

[0097] The resistance value of the negative characteristic thermistor 25d decreases when the temperature exceeds a predetermined temperature (Curie temperature).

[0098] In addition, the resistance value of the positive characteristic thermistor 25f increases when the temperature exceeds a predetermined temperature (Curie temperature). In this case, for example, the Curie temperature of the positive characteristic thermistor 25f becomes higher than the Curie temperature of the negative characteristic thermistor 25d. The negative characteristic thermistor 25d and the positive characteristic thermistor 25f can be set as surface mount type thermistors, for example.

[0099] The resistor 25e may be, for example, a surface mount resistor, a resistor with leads (metal oxide film resistor), or a film resistor formed using a screen printing method or the like. Figure 1 The resistor 25e shown as an example is a surface mount resistor.

[0100] As described later, the current setting circuit 25c2 generates a setting current Ib required when the current driver 25c1 sets the output current Ia flowing to the light emitting element 22 based on the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal. In addition, the current setting circuit 25c2 adjusts the setting current Ib based on the resistance value of the positive characteristic thermistor 25f electrically connected to the ISET terminal.

[0101] Here, a light emitting circuit 120a of a comparative example will be described.

[0102] Figure 4 2 is a circuit diagram for illustrating a light emitting circuit 120 a of a comparative example.

[0103] like Figure 4 As shown, the light emitting circuit 120a includes the light emitting element 22, the resistor 25a, the protection element 25b, the control element 25c, the negative characteristic thermistor 25d, and the resistor 25e. That is, the light emitting circuit 120a does not include the positive characteristic thermistor 25f provided in the light emitting circuit 20a.

[0104] Figure 5 and Figure 6 It is a graph for illustrating the effects of the light emitting circuit 120a of the comparative example.

[0105] also, Figure 5 and Figure 6 "La" is the total luminous flux required when the ambient temperature of the light emitting element 22 is 20°C (for example, 350 lumens). "Lb" is the total luminous flux required when the ambient temperature of the light emitting element 22 is 60°C (for example, 280 lumens).

[0106] like Figure 5 As shown, since the control element 25c is also provided in the light emitting circuit 120a, the current flowing in the light emitting element 22 can be controlled according to the ambient temperature of the light emitting element 22. That is, temperature derating is also performed in the light emitting circuit 120a.

[0107] In this case, the current setting circuit 25c2 generates the setting current Ib based on the change in the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal. In addition, the current setting circuit 25c2 adjusts the setting current Ib based on the terminal voltage generated at the ISET terminal. Since only the resistor 25e is connected to the ISET terminal, a terminal voltage corresponding to the resistance value of the resistor 25e is generated.

[0108] Furthermore, the current driver 25c1 sets a target value of the output current Ia based on the setting current Ib from the current setting circuit 25c2.

[0109] When the temperature of the negative characteristic thermistor 25d is below the Curie temperature of the negative characteristic thermistor 25d (for example, the ambient temperature of the light emitting element 22 is below 40°C), the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal hardly changes. Therefore, the setting current Ib generated based on the resistance value of the negative characteristic thermistor 25d by the current setting circuit 25c2 hardly changes. In this case, for example, the resistance value of the resistor 25e electrically connected to the ISET terminal is set so that the output current Ia that satisfies the total luminous flux La required when the temperature is 20°C is output from the current driver 25c1. In this case, for example, if the resistance value of the resistor 25e electrically connected to the ISET terminal is reduced, the output current Ia increases. In addition, if the resistance value of the resistor 25e electrically connected to the ISET terminal is increased, the output current Ia decreases.

[0110] If the temperature of the negative characteristic thermistor 25d exceeds the Curie temperature of the negative characteristic thermistor 25d (for example, the ambient temperature of the light emitting element 22 exceeds 40°C), the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases. Therefore, the current setting circuit 25c2 generates the setting current Ib based on the change in the resistance value of the negative characteristic thermistor 25d. In this case, if the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases, the output current Ia decreases.

[0111] In this case, if Figure 5 As shown, there may be a situation where the total luminous flux Lb required when the ambient temperature of the light emitting element 22 reaches a predetermined temperature (for example, 60° C.) cannot be satisfied.

[0112] In this case, the set current Ib and thus the output current Ia can be adjusted according to the resistance value of the resistor 25e electrically connected to the ISET terminal.

[0113] Therefore, if a resistor 25e having an appropriate resistance value is selected and electrically connected to the ISET terminal, or the resistance value of the resistor 25e is changed, Figure 6 As shown, the total luminous flux Lb required when the predetermined temperature (for example, 60° C.) is reached can be satisfied. For example, if the resistance value of the resistor 25 e electrically connected to the ISET terminal is reduced, the output current Ia can be adjusted to increase.

[0114] However, if this is the case, when the ambient temperature of the light emitting element 22 further increases (for example, to 80° C.), the decrease in total luminous flux (the decrease in the output current Ia flowing in the light emitting element 22) becomes too small. Therefore, the temperature of the light emitting element 22 becomes too high, and there is a concern that the temperature of the light emitting element 22 exceeds the maximum junction temperature.

[0115] Therefore, in the light emitting circuit 20a of the present embodiment, a positive characteristic thermistor 25f connected in series with a resistor 25e is further electrically connected to the ISET terminal of the control element 25c.

[0116] If the positive characteristic thermistor 25f is provided, a terminal voltage is generated at the RTH terminal based on the change in the ambient temperature of the light emitting element 22. Therefore, based on the change in the ambient temperature of the light emitting element 22, the set current Ib and the output current Ia can be changed.

[0117] In this case, when the temperature of the positive characteristic thermistor 25f is lower than the Curie temperature of the positive characteristic thermistor 25f (for example, the ambient temperature of the light emitting element 22 is lower than 60°C), the resistance value of the positive characteristic thermistor 25f hardly changes. When the ambient temperature of the light emitting element 22 is near the Curie temperature of the positive characteristic thermistor 25f, the amount of change in the resistance value is small.

[0118] As the temperature of the positive characteristic thermistor 25f increases above the Curie temperature of the positive characteristic thermistor 25f (for example, as the ambient temperature of the light emitting element 22 increases above 60°C), the resistance value of the positive characteristic thermistor 25f increases sharply.

[0119] Figure 7 This is a graph for illustrating the effects of the light emitting circuit 20a of the present embodiment.

[0120] In a region where the temperature of the negative characteristic thermistor 25d is lower than the Curie temperature of the negative characteristic thermistor 25d and the temperature of the positive characteristic thermistor 25f is lower than the Curie temperature of the positive characteristic thermistor 25f (for example, a temperature region where the ambient temperature of the light emitting element 22 is lower than 40°C), the set current Ib is set based on the resistance value of the resistor 25e electrically connected to the ISET terminal. Figure 7 As shown, the total luminous flux of light emitted from the light emitting element 22 hardly changes.

[0121] In a region where the temperature of the negative characteristic thermistor 25d exceeds the Curie temperature of the negative characteristic thermistor 25d and the temperature of the positive characteristic thermistor 25f is below the Curie temperature of the positive characteristic thermistor 25f (for example, a temperature region where the ambient temperature of the light emitting element 22 exceeds 40°C (an example of the first temperature) and is below 60°C (an example of the second temperature)), the set current Ib is set based on the decrease in the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal. If the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases, the output current Ia decreases. Therefore, if Figure 7 As shown, the total luminous flux of light emitted from the light emitting element 22 decreases as the temperature rises. That is, the output current Ia decreases due to temperature derating, so the total luminous flux of light emitted from the light emitting element 22 decreases.

[0122] Furthermore, in a region where the temperature of the negative characteristic thermistor 25d exceeds the Curie temperature of the negative characteristic thermistor 25d and the temperature of the positive characteristic thermistor 25f exceeds the Curie temperature of the positive characteristic thermistor 25f (for example, a temperature region where the ambient temperature of the light emitting element 22 exceeds 60°C), the set current Ib is adjusted in accordance with the increase in the resistance value of the positive characteristic thermistor 25f electrically connected to the ISET terminal, and the ratio of the reduction of the output current Ia increases. If the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the positive characteristic thermistor 25f increases as the resistance value of the positive characteristic thermistor 25f increases, the output current Ia further decreases. As a result, Figure 7 As shown, the ratio of total luminous flux reduction can be increased.

[0123] That is, in a region where the ambient temperature of the light emitting element 22 is high, the ratio at which the total luminous flux can be reduced can be changed.

[0124] In this case, for example, when the required total luminous flux Lb is specified when the ambient temperature of the light emitting element 22 is 60°C, it is preferred to measure the temperature (e.g., 120°C±10°C) of the positive characteristic thermistor 25f when the ambient temperature of the light emitting element 22 is 60°C, and select a positive characteristic thermistor 25f whose Curie temperature is the measured temperature (e.g., 120°C±10°C). In this way, the required total luminous flux can be obtained in the region where the ambient temperature of the light emitting element 22 is high, and the temperature rise of the light emitting element 22 can be suppressed.

[0125] As described above, if the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases, the current setting circuit 25c2 generates the setting current Ib that reduces the output current Ia. If the resistance value of the positive characteristic thermistor 25f electrically connected to the ISET terminal increases, the current setting circuit 25c2 adjusts the setting current Ib so that the ratio of the reduction of the output current Ia increases.

[0126] Here, when the temperature of the light emitting element 22 rises, the total luminous flux of the light emitted from the light emitting element 22 may decrease.

[0127] Figure 8 This is a graph for illustrating another effect of the light emitting circuit 120 a of the comparative example.

[0128] When the ambient temperature of the light emitting element 22 is low (eg, 40° C. or lower), the resistance value of the negative characteristic thermistor 25 d electrically connected to the RTH terminal hardly changes, so a substantially constant output current Ia flows through the light emitting element 22 .

[0129] Therefore, if Figure 8 As shown, in a region where the ambient temperature of the light emitting element 22 is low (for example, a region of 40° C. or less), the total luminous flux may decrease as the ambient temperature of the light emitting element 22 increases.

[0130] Fig. 9 2 is a circuit diagram for illustrating a light emitting circuit 20 b according to another embodiment.

[0131] Fig.10 It is a graph for illustrating the effect of the light emitting circuit 20b.

[0132] like Fig. 9 As shown, the light emitting circuit 20b includes, for example, a light emitting element 22, a resistor 25a, a protection element 25b, a control element 25c, a negative characteristic thermistor 25d, a resistor 25e, a positive characteristic thermistor 25f, and a negative characteristic thermistor 25g (equivalent to an example of a second negative characteristic thermistor). That is, the light emitting circuit 20b may further include a negative characteristic thermistor 25g in the light emitting circuit 20a.

[0133] The negative characteristic thermistor 25g can be connected in series with the positive characteristic thermistor 25f and the resistor 25e connected in series. The positive characteristic thermistor 25f, the resistor 25e, and the negative characteristic thermistor 25g connected in series are electrically connected to the ISET terminal (equivalent to an example of the second circuit). The negative characteristic thermistor 25d is electrically connected to the RTH terminal (equivalent to an example of the first circuit).

[0134] The region where the ambient temperature of the light emitting element 22 is low (for example, a region below 40°C) becomes a region where the temperature of the positive characteristic thermistor 25f is below the Curie temperature of the positive characteristic thermistor 25f, and thus the resistance value of the positive characteristic thermistor 25f is substantially constant. Therefore, in the region where the ambient temperature of the light emitting element 22 is low, the set current Ib and thus the output current Ia change based on the change in the resistance value of the negative characteristic thermistor 25g electrically connected to the ISET terminal.

[0135] Since the resistance value of the negative characteristic thermistor 25g electrically connected to the ISET terminal decreases as the temperature rises, if the ambient temperature of the light emitting element 22 rises in a region where the ambient temperature of the light emitting element 22 is low, the resistance value of the negative characteristic thermistor 25g decreases.

[0136] If the combined resistance value of the resistor 25e, the positive characteristic thermistor 25f, and the negative characteristic thermistor 25g electrically connected to the ISET terminal decreases as the resistance value of the negative characteristic thermistor 25g decreases, the output current Ia increases. Fig.10 As shown in FIG. 1 , in the region where the ambient temperature of the light emitting element 22 is low, the set current Ib and the output current Ia can be increased as the ambient temperature of the light emitting element 22 increases. That is, in the region where the ambient temperature of the light emitting element 22 is low, the decrease in the total luminous flux accompanying the increase in the ambient temperature of the light emitting element 22 can be offset by the increase in the total luminous flux caused by the increase in the output current Ia. As a result, for example, Figure 7 As shown, in a region where the ambient temperature of the light emitting element 22 is low, the total luminous flux variation can be suppressed.

[0137] As described above, in the temperature range below the Curie temperature of the positive characteristic thermistor 25f, the current setting circuit 25c2 generates the setting current Ib for increasing the output current Ia based on the decrease in the resistance value of the negative characteristic thermistor 25g electrically connected to the ISET terminal.

[0138] Fig.11 2 is a circuit diagram for illustrating a light emitting circuit 20c according to another embodiment.

[0139] like Fig.11 As shown in FIG. 1 , the light emitting circuit 20c includes, for example, a light emitting element 22, a resistor 25a, a protection element 25b, a control element 25c, a negative characteristic thermistor 25d, a resistor 25e, and a positive characteristic thermistor 25f. That is, the light emitting circuit 20c replaces the connection position of the negative characteristic thermistor 25d and the positive characteristic thermistor 25f in the light emitting circuit 20a.

[0140] In this case, for example, a resistor 25e and a negative characteristic thermistor 25d (corresponding to an example of the second circuit) connected in series are electrically connected to the ISET terminal, and a positive characteristic thermistor 25f (corresponding to an example of the first circuit) is electrically connected to the RTH terminal.

[0141] In this case, the current setting circuit 25c2 generates the setting current Ib required when the current driver 25c1 sets the output current Ia flowing to the light emitting element 22 based on the resistance value of the positive characteristic thermistor 25f electrically connected to the RTH terminal. In addition, the current setting circuit 25c2 adjusts the setting current Ib based on the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the negative characteristic thermistor 25d.

[0142] Here, the current setting circuit 25c2 of the light emitting circuit 20c is set to operate differently from the current setting circuit 25c2 of the light emitting circuit 20a.

[0143] When the resistance value of the positive characteristic thermistor 25f electrically connected to the RTH terminal increases, the current setting circuit 25c2 performs adjustment to reduce the output current Ia.

[0144] When the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the negative characteristic thermistor 25d decreases, the current setting circuit 25c2 performs adjustment to increase the rate at which the output current Ia is reduced.

[0145] If the positive characteristic thermistor 25f is provided, a terminal voltage is generated at the RTH terminal based on the change in the ambient temperature of the light emitting element 22. Therefore, based on the change in the ambient temperature of the light emitting element 22, the set current Ib and the output current Ia can be changed.

[0146] In this case, when the temperature of the positive characteristic thermistor 25f is lower than the Curie temperature of the positive characteristic thermistor 25f (for example, the ambient temperature of the light emitting element 22 is lower than 40°C), the resistance value of the positive characteristic thermistor 25f hardly changes. When the ambient temperature of the light emitting element 22 is near the Curie temperature of the positive characteristic thermistor 25f, the amount of change in the resistance value is small.

[0147] As the temperature of the positive characteristic thermistor 25f increases above the Curie temperature of the positive characteristic thermistor 25f (for example, as the ambient temperature of the light emitting element 22 increases above 40°C), the resistance value of the positive characteristic thermistor 25f increases sharply.

[0148] Therefore, the current setting circuit 25c2 generates a setting current Ib for reducing the output current Ia based on the increase in the resistance value of the positive characteristic thermistor 25f.

[0149] In addition, if the ambient temperature of the light emitting element 22 becomes higher (for example, the ambient temperature of the light emitting element 22 is higher than 60° C.), the resistance value of the negative characteristic thermistor 25d electrically connected to the ISET terminal decreases, so the current setting circuit 25c2 increases the ratio of reducing the output current Ia based on the reduction in the resistance value of the negative characteristic thermistor 25d.

[0150] As described above, the structure of the light emitting circuit 20c can also achieve the same effects as those of the light emitting circuit 20a.

[0151] Fig.12 20 d is a circuit diagram for illustrating a light emitting circuit 20 d according to another embodiment.

[0152] like Fig.12 As shown, the light emitting circuit 20d includes, for example, a light emitting element 22, a resistor 25a, a protection element 25b, a control element 25c, a negative characteristic thermistor 25d, and a resistor 25e. That is, the light emitting circuit 20d replaces the positive characteristic thermistor 25f in the light emitting circuit 20a with a negative characteristic thermistor 25d.

[0153] In this case, for example, a resistor 25e and a negative characteristic thermistor 25d (corresponding to an example of the second circuit) connected in series are electrically connected to the ISET terminal. The negative characteristic thermistor 25d (corresponding to an example of the first circuit) is electrically connected to the RTH terminal.

[0154] In this case, the current setting circuit 25c2 generates the setting current Ib required when the current driver 25c1 sets the output current Ia flowing to the light emitting element 22 based on the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal. In addition, the current setting circuit 25c2 adjusts the setting current Ib based on the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the negative characteristic thermistor 25d.

[0155] Here, the current setting circuit 25c2 of the light emitting circuit 20d is set to operate differently from the current setting circuit 25c2 of the light emitting circuit 20a.

[0156] When the resistance value of the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases, the current setting circuit 25c2 performs adjustment to decrease the output current Ia.

[0157] When the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the negative characteristic thermistor 25d decreases, the current setting circuit 25c2 performs adjustment to increase the ratio at which the output current Ia is reduced.

[0158] Therefore, similarly to the case of the light emitting circuit 20a, the current setting circuit 25c2 can change the setting current Ib and thus the output current Ia based on the change in the ambient temperature of the light emitting element 22. Also, similarly to the case of the light emitting circuit 20c, the setting current Ib can be adjusted.

[0159] As described above, the structure of the light emitting circuit 20d can also achieve the same effects as those of the light emitting circuit 20a.

[0160] Fig.13 20e is a circuit diagram for illustrating a light emitting circuit 20e according to another embodiment.

[0161] like Fig.13 As shown, the light emitting circuit 20e includes, for example, a light emitting element 22, a resistor 25a, a protection element 25b, a control element 25c, a positive characteristic thermistor 25f, and a resistor 25e. That is, the light emitting circuit 20e replaces the negative characteristic thermistor 25d in the light emitting circuit 20a with a positive characteristic thermistor 25f.

[0162] In this case, for example, a resistor 25e and a positive thermistor 25f (corresponding to an example of the second circuit) connected in series are electrically connected to the ISET terminal. The positive thermistor 25f (corresponding to an example of the first circuit) is electrically connected to the RTH terminal.

[0163] In this case, the current setting circuit 25c2 generates the setting current Ib required when the current driver 25c1 sets the output current Ia flowing to the light emitting element 22 based on the resistance value of the positive characteristic thermistor 25f electrically connected to the RTH terminal. In addition, the current setting circuit 25c2 adjusts the setting current Ib based on the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the positive characteristic thermistor 25f.

[0164] Here, the current setting circuit 25c2 of the light emitting circuit 20e is set to operate differently from the current setting circuit 25c2 of the light emitting circuit 20a.

[0165] When the resistance value of the positive characteristic thermistor 25f electrically connected to the RTH terminal increases, the current setting circuit 25c2 performs adjustment to reduce the output current Ia.

[0166] If the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the positive characteristic thermistor 25f increases, the current setting circuit 25c2 performs adjustment to increase the ratio at which the output current Ia is reduced.

[0167] Therefore, similarly to the light emitting circuit 20c, the current setting circuit 25c2 can change the setting current Ib and thus the output current Ia based on the change in the ambient temperature of the light emitting element 22. Also, similarly to the light emitting circuit 20a, the setting current Ib can be adjusted.

[0168] As described above, the structure of the light emitting circuit 20e can also achieve the same effects as those of the light emitting circuit 20a.

[0169] Fig.14 20f is a circuit diagram for illustrating a light emitting circuit 20f according to another embodiment.

[0170] like Fig.14 As shown in FIG. 1 , the light emitting circuit 20f includes, for example, a light emitting element 22, a resistor 25a, a protective element 25b, a control element 25c, a negative characteristic thermistor 25d, a resistor 25e, a positive characteristic thermistor 25f, and a positive characteristic thermistor 25h (corresponding to an example of a first positive characteristic thermistor). That is, the light emitting circuit 20f replaces the connection position of the positive characteristic thermistor 25f and the negative characteristic thermistor 25d in the light emitting circuit 20c, and further connects the positive characteristic thermistor 25h and the negative characteristic thermistor 25d in series.

[0171] In this case, the positive characteristic thermistor 25h and the negative characteristic thermistor 25d connected in series are electrically connected to the RTH terminal (corresponding to an example of the first circuit). The resistor 25e and the positive characteristic thermistor 25f connected in series are electrically connected to the ISET terminal (corresponding to an example of the second circuit).

[0172] Here, the current setting circuit 25c2 of the light emitting circuit 20f is set to operate in the same manner as the current setting circuit 25c2 of the light emitting circuit 20a or the current setting circuit 25c2 of the light emitting circuit 20c.

[0173] When the combined resistance value of the positive characteristic thermistor 25h and the negative characteristic thermistor 25d electrically connected to the RTH terminal decreases, the current setting circuit 25c2 performs adjustment to decrease the output current Ia.

[0174] If the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the positive characteristic thermistor 25f increases, the current setting circuit 25c2 performs adjustment to increase the ratio at which the output current Ia is reduced.

[0175] Since the area where the ambient temperature of the light emitting element 22 is low (for example, an area below 40°C) becomes an area where the temperature of the positive characteristic thermistor 25f electrically connected to the ISET terminal is below the Curie temperature of the positive characteristic thermistor 25f, the combined resistance value of the resistor 25e and the positive characteristic thermistor 25f is substantially constant.

[0176] Therefore, in a region where the ambient temperature of the light emitting element 22 is low, the set current Ib and thus the output current Ia change based on changes in the combined resistance value of the positive characteristic thermistor 25h and the negative characteristic thermistor 25d electrically connected to the RTH terminal.

[0177] The Curie temperature of the positive characteristic thermistor 25h and the Curie temperature of the negative characteristic thermistor 25d electrically connected to the RTH terminal are adjusted so that in an area where the ambient temperature of the light emitting element 22 is low (for example, an area below 40°C), as the temperature rises, the combined resistance value of the positive characteristic thermistor 25h and the negative characteristic thermistor 25d increases, and when the temperature further rises (for example, when it becomes an area exceeding 40°C), the combined resistance value of the positive characteristic thermistor 25h and the negative characteristic thermistor 25d turns to decrease.

[0178] In a region where the ambient temperature of the light emitting element 22 is low (e.g., a region below 40°C), if the combined resistance value of the positive characteristic thermistor 25h and the negative characteristic thermistor 25d electrically connected to the RTH terminal increases as the resistance value of the positive characteristic thermistor 25h increases, the output current Ia increases. Fig.10 As shown in FIG. 1 , in the region where the ambient temperature of the light emitting element 22 is low, the set current Ib and the output current Ia can be increased as the ambient temperature of the light emitting element 22 increases. That is, in the region where the ambient temperature of the light emitting element 22 is low, the decrease in the total luminous flux accompanying the increase in the ambient temperature of the light emitting element 22 can be offset by the increase in the total luminous flux caused by the increase in the output current Ia. As a result, for example, Figure 7 As shown, in a region where the ambient temperature of the light emitting element 22 is low, the total luminous flux variation can be suppressed.

[0179] Furthermore, if the ambient temperature of the light-emitting element 22 rises, the reduction ratio of the resistance value of the negative characteristic thermistor 25d becomes greater than the increase ratio of the resistance value of the positive characteristic thermistor 25h (for example, when it becomes a region exceeding 40°C), and the combined resistance value of the positive characteristic thermistor 25h and the negative characteristic thermistor 25d electrically connected to the RTH terminal changes from increasing to decreasing, so the set current Ib and then the output current Ia decreases.

[0180] Furthermore, in a region where the temperature of the positive characteristic thermistor 25f electrically connected to the ISET terminal exceeds the Curie temperature of the positive characteristic thermistor 25f (for example, a temperature region where the ambient temperature of the light emitting element 22 exceeds 60°C), the set current Ib is adjusted in accordance with the increase in the resistance value of the positive characteristic thermistor 25f electrically connected to the ISET terminal, and the ratio of the reduction of the output current Ia increases. If the combined resistance value of the resistor 25e electrically connected to the ISET terminal and the positive characteristic thermistor 25f increases as the resistance value of the positive characteristic thermistor 25f increases, the output current Ia further decreases. As a result, Fig.10 As shown, the ratio at which the output current Ia can be reduced is increased.

[0181] That is, in a region where the ambient temperature of the light emitting element 22 is high, the ratio at which the total luminous flux can be reduced can be changed.

[0182] As described above, the structure of the light emitting circuit 20f can also achieve the same effects as those of the light emitting circuit 20c.

[0183] (Vehicle Lighting)

[0184] In one embodiment of the present invention, a vehicle lamp 100 including the vehicle lighting device 1 is provided. The description of the vehicle lighting device 1 and the modified examples of the vehicle lighting device 1 (for example, the light emitting circuit 20b, or an example having the features of the present invention by adding, deleting or changing the design of components appropriately by a person skilled in the art) can be applied to the vehicle lamp 100.

[0185] In addition, the following description takes the case where the vehicle lamp 100 is a front combination lamp provided in a car as an example. However, the vehicle lamp 100 is not limited to a front combination lamp provided in a car. The vehicle lamp 100 may be any vehicle lamp provided in a car, a train, or the like.

[0186] Fig.15 It is a schematic partial cross-sectional view for illustrating the vehicle lamp 100 .

[0187] like Fig.15 As shown, the vehicle lamp 100 includes, for example, the vehicle lighting device 1 , a housing 101 , a cover 102 , an optical component 103 , a sealing member 104 , and a connector 105 .

[0188] The vehicle lighting device 1 is mounted on the frame 101. The frame 101 holds the mounting portion 11. The frame 101 is in the shape of a box with one end side opened. The frame 101 is formed of, for example, a light-proof resin or the like. An assembly hole 101a is provided on the bottom surface of the frame 101, and the assembly hole 101a is inserted into the portion of the mounting portion 11 provided with the bayonet 12. A recess is provided around the periphery of the assembly hole 101a, into which the bayonet 12 provided on the mounting portion 11 is inserted. In addition, although the case where the assembly hole 101a is directly provided on the frame 101 is illustrated, an assembly component having the assembly hole 101a may also be provided on the frame 101.

[0189] When the vehicle lighting device 1 is mounted on the vehicle lamp 100, the portion of the mounting portion 11 provided with the bayonet 12 is inserted into the mounting hole 101a, and the vehicle lighting device 1 is rotated. Then, for example, the bayonet 12 is held by the fitting portion provided on the periphery of the mounting hole 101a. This mounting method is called twist lock.

[0190] The cover 102 is provided to close the opening of the housing 101. The cover 102 is formed of a light-transmitting resin or the like. The cover 102 may also have a function of a lens or the like.

[0191] The light emitted from the vehicle lighting device 1 enters the optical component 103. The optical component 103 performs reflection, diffusion, light guiding, light focusing, formation of a predetermined light distribution pattern, etc. of the light emitted from the vehicle lighting device 1. For example, Fig.15 The optical member 103 shown as an example is a reflector. In this case, the optical member 103 reflects the light emitted from the vehicle lighting device 1 to form a predetermined light distribution pattern.

[0192] The sealing member 104 is provided between the flange 13 and the frame 101. The sealing member 104 is annular and is formed of an elastic material such as rubber or silicone resin.

[0193] When the vehicle lighting device 1 is mounted on the vehicle lamp 100, the sealing member 104 is sandwiched between the flange 13 and the frame 101. Therefore, the internal space of the frame 101 can be sealed by the sealing member 104. In addition, the bayonet 12 is pressed to the frame 101 by the elastic force of the sealing member 104. Therefore, the vehicle lighting device 1 can be prevented from being separated from the frame 101.

[0194] The connector 105 is fitted with the ends of the plurality of power supply terminals 31 exposed inside the connector holder 15. The lighting circuit is electrically connected to the connector 105. Therefore, by fitting the connector 105 to the ends of the plurality of power supply terminals 31, the lighting circuit and the like can be electrically connected to the light emitting element 22.

[0195] In addition, a sealing member 105a is provided in the connector 105. When the connector 105 having the sealing member 105a is inserted into the inside of the connector holder 15, the inside of the connector holder 15 is sealed watertightly.

[0196] Several embodiments of the present invention are illustrated above, but these embodiments are only provided as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, changes, etc. can be made without departing from the scope of the invention. These embodiments or their modifications are included in the scope or spirit of the invention, and are included in the invention described in the claims and their equivalents. In addition, the embodiments described above can be implemented in combination with each other.

[0197] The following are additional notes related to the above-described embodiment.

[0198] (Note 1)

[0199] A vehicle lighting device, comprising:

[0200] Lamp holder;

[0201] A substrate, disposed on one end side of the lamp holder;

[0202] A light emitting element is disposed on the substrate;

[0203] a control element, disposed on the substrate and having a current driver and a current setting circuit, wherein an output side of the current driver is electrically connected to the light-emitting element, and an output side of the current setting circuit is electrically connected to the current driver;

[0204] a first circuit, which is provided on the substrate and is electrically connected to the first input side of the current setting circuit, and whose resistance value changes according to the ambient temperature of the light emitting element; and

[0205] a second circuit, which is disposed on the substrate and is electrically connected to the second input side of the current setting circuit, and whose resistance value changes according to the ambient temperature of the light emitting element;

[0206] The current setting circuit

[0207] In a temperature range where the ambient temperature of the light emitting element exceeds a first temperature and is not more than a second temperature higher than the first temperature, an output current flowing to the light emitting element is reduced as the ambient temperature of the light emitting element increases based on a change in the resistance value of the first circuit,

[0208] In a temperature region where the ambient temperature of the light emitting element exceeds the second temperature, based on a change in the resistance value of the second circuit, a ratio of reducing the output current flowing to the light emitting element increases as the ambient temperature of the light emitting element rises.

[0209] (Note 2)

[0210] According to the vehicle lighting device described in Appendix 1, in a temperature region where the ambient temperature of the light-emitting element is lower than the first temperature, the current setting circuit increases the output current flowing to the light-emitting element as the ambient temperature of the light-emitting element rises based on the change in the resistance value of the second circuit.

[0211] (Note 3)

[0212] According to the vehicle lighting device described in Note 1 or 2, in a temperature region where the ambient temperature of the light-emitting element is lower than the first temperature, the current setting circuit increases the output current flowing to the light-emitting element as the ambient temperature of the light-emitting element rises based on the change in the resistance value of the first circuit.

[0213] (Note 4)

[0214] The vehicle lighting device according to any one of Supplementary Notes 1 to 3, wherein the first circuit comprises a first negative characteristic thermistor, or a first positive characteristic thermistor, or the first negative characteristic thermistor and the first positive characteristic thermistor connected in series,

[0215] The second circuit includes a second negative characteristic thermistor, a second positive characteristic thermistor, or the second negative characteristic thermistor and the second positive characteristic thermistor connected in series.

[0216] (Note 5)

[0217] According to the vehicle lighting device described in Appendix 4, the current setting circuit generates a setting current required for the current driver to set the output current flowing to the light-emitting element based on the resistance value of the first negative characteristic thermistor, and adjusts the setting current based on the resistance value of the second positive characteristic thermistor.

[0218] (Note 6)

[0219] According to the vehicle lighting device described in Appendix 5, in the current setting circuit, if the resistance value of the first negative characteristic thermistor decreases, the set current is generated to reduce the output current, and if the resistance value of the second positive characteristic thermistor increases, the set current is adjusted to increase the ratio of the output current reduction.

[0220] (Note 7)

[0221] The vehicle lighting device according to any one of Supplementary Notes 4 to 6, wherein in a temperature range below the Curie temperature of the second positive characteristic thermistor,

[0222] The current setting circuit generates the setting current for increasing the output current based on a decrease in the resistance value of the second negative characteristic thermistor.

[0223] (Note 8)

[0224] A vehicle lamp, comprising:

[0225] The vehicle lighting device according to any one of Supplementary Notes 1 to 7; and

[0226] The frame is used to assemble the vehicle lighting device.

Claims

1. A vehicle lighting device, comprising: Lamp holder; A substrate, disposed on one end side of the lamp holder; A light emitting element is disposed on the substrate; A control element, disposed on the substrate, and having a current driver and a current setting circuit, wherein an output side of the current driver is electrically connected to the light-emitting element, and an output side of the current setting circuit is electrically connected to the current driver; a first circuit, which is disposed on the substrate and is electrically connected to the first input side of the current setting circuit, and whose resistance value changes according to the ambient temperature of the light-emitting element; as well as a second circuit, which is disposed on the substrate and is electrically connected to the second input side of the current setting circuit, and whose resistance value changes according to the ambient temperature of the light emitting element; The current setting circuit In a temperature range where the ambient temperature of the light emitting element exceeds a first temperature and is not more than a second temperature higher than the first temperature, an output current flowing to the light emitting element is reduced as the ambient temperature of the light emitting element increases based on a change in the resistance value of the first circuit, In a temperature region where the ambient temperature of the light emitting element exceeds the second temperature, based on a change in the resistance value of the second circuit, a ratio of reducing the output current flowing to the light emitting element increases as the ambient temperature of the light emitting element rises.

2. The vehicle lighting device according to claim 1, wherein the current setting circuit increases the output current flowing to the light emitting element as the ambient temperature of the light emitting element rises based on the change in the resistance value of the second circuit in a temperature region where the ambient temperature of the light emitting element is lower than the first temperature.

3. The vehicle lighting device according to claim 1, wherein the current setting circuit increases the output current flowing to the light emitting element as the ambient temperature of the light emitting element rises based on the change in the resistance value of the first circuit in a temperature region where the ambient temperature of the light emitting element is lower than the first temperature.

4. The vehicle lighting device according to claim 1, wherein the first circuit comprises a first negative characteristic thermistor, a first positive characteristic thermistor, or the first negative characteristic thermistor and the first positive characteristic thermistor connected in series, The second circuit includes a second negative characteristic thermistor, a second positive characteristic thermistor, or the second negative characteristic thermistor and the second positive characteristic thermistor connected in series.

5. The vehicle lighting device according to claim 4, wherein the current setting circuit generates a setting current required for the current driver to set the output current flowing to the light-emitting element based on the resistance value of the first negative characteristic thermistor, and adjusts the setting current based on the resistance value of the second positive characteristic thermistor.

6. The vehicle lighting device according to claim 5, wherein in the current setting circuit, if the resistance value of the first negative characteristic thermistor decreases, the set current is generated to reduce the output current, and if the resistance value of the second positive characteristic thermistor increases, the set current is adjusted to increase the ratio of the output current reduction.

7. The vehicle lighting device according to any one of claims 4 to 6, wherein in a temperature range below the Curie temperature of the second positive characteristic thermistor, The current setting circuit generates the setting current for increasing the output current based on a decrease in the resistance value of the second negative characteristic thermistor.

8. A vehicle lamp, comprising: The vehicle lighting device according to claim 1; as well as The frame is used to assemble the vehicle lighting device.

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