JP2022129512A - Vehicular lighting device and vehicular lamp - Google Patents

Abstract

To provide a vehicular lighting device and a vehicular lamp which are capable of ensuring a required total luminous flux even when an input voltage is getting close to a lower limit of an operation voltage range and suppressing a rapid change of the total luminous flux when the input voltage is close to the lower limit of the operation voltage range.SOLUTION: A vehicular lighting device has: a first light-emitting circuit which comprises a plurality of first light-emitting elements connected in series; a second light-emitting circuit which comprises a plurality of second light-emitting elements connected in series and is connected in parallel with the first light-emitting circuit; and a control part which is electrically connected with the first light-emitting circuit and the second light-emitting circuit. The number of the first light-emitting elements is greater than the number of the second light-emitting elements. The control part maintains current flowing in at least the second light-emitting circuit nearly constant within an operation voltage range of the vehicular lighting device.SELECTED DRAWING: Figure 5

Description

TECHNICAL FIELD Embodiments of the present invention relate to vehicle lighting devices and vehicle lamps.

2. Description of the Related Art From the viewpoint of energy saving and long life, vehicle lighting devices equipped with light-emitting diodes are becoming popular instead of vehicle lighting devices equipped with filaments. Generally, a vehicle lighting device is provided with a plurality of light emitting diodes connected in series.

Here, the voltage applied to the vehicle lighting device fluctuates. Therefore, an operating voltage range (voltage fluctuation range) is defined in the vehicle lighting device.
Also, light emitting diodes have a forward voltage drop. Therefore, when the voltage applied to the plurality of light-emitting diodes connected in series decreases, the amount of light emitted from the plurality of light-emitting diodes decreases, and the total luminous flux of the light emitted from the vehicle lighting device reaches the specified value. There is a risk that it will be less than

Therefore, a technique has been proposed in which, when the voltage (input voltage) applied to the vehicle lighting device is lowered, current does not flow through some of the plurality of light emitting diodes connected in series. ing.
In this way, even if the input voltage drops to near the lower limit of the operating voltage range, the required total luminous flux can be ensured.
However, when current is not applied to some of the light emitting diodes, the current flowing through the remaining light emitting diodes suddenly increases, resulting in a sudden increase in the total luminous flux of the light emitted from the vehicle lighting device. A problem arises.

Therefore, it is possible to secure the required total luminous flux even when the input voltage is near the lower limit of the operating voltage range, and to suppress a sudden change in the total luminous flux near the lower limit of the operating voltage range. It was hoped that the technology could be developed.

JP 2015-63252 A

The problem to be solved by the present invention is to ensure the necessary total luminous flux even when the input voltage is near the lower limit of the operating voltage range, and to reduce the total luminous flux sharply near the lower limit of the operating voltage range. An object of the present invention is to provide a vehicle lighting device and a vehicle lamp that can suppress change.

A vehicle lighting device according to an embodiment includes: a first light emitting circuit having a plurality of first light emitting elements connected in series; and a plurality of second light emitting elements connected in series. a second light emitting circuit connected in parallel to the circuit; and a controller electrically connected to the first light emitting circuit and the second light emitting circuit. The number of the first light emitting elements is greater than the number of the second light emitting elements. The control unit keeps the current flowing through at least the second light emitting circuit substantially constant within the operating voltage range of the vehicle lighting device.

According to the embodiment of the present invention, the required total luminous flux can be secured even when the input voltage is near the lower limit of the operating voltage range, and the total luminous flux changes abruptly near the lower limit of the operating voltage range. It is possible to provide a vehicle lighting device and a vehicle lighting device that can suppress the occurrence of overheating.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic perspective view for illustrating the vehicle lighting apparatus which concerns on this Embodiment. FIG. 2 is a schematic cross-sectional view of the vehicle lighting device in FIG. 1 taken along the line AA. (a) and (b) are circuit diagrams for illustrating a light-emitting module according to a comparative example. FIG. 5 is a graph diagram illustrating the relationship between the input voltage and the total luminous flux in a light emitting module according to a comparative example; 1 is a circuit diagram illustrating a light emitting module according to an embodiment; FIG. FIG. 4 is a graph diagram illustrating the relationship between the input voltage and the total luminous flux in the light-emitting module according to the present embodiment; 1 is a schematic partial cross-sectional view for illustrating a vehicle lamp; FIG.

Hereinafter, embodiments will be illustrated with reference to the drawings. In addition, in each drawing, the same reference numerals are given to the same constituent elements, and detailed description thereof will be omitted as appropriate.

(Vehicle lighting device)
The vehicle lighting device 1 according to the present embodiment can be installed in, for example, an automobile or a railroad vehicle. The vehicle lighting device 1 provided in an automobile includes, for example, a front combination light (for example, a combination of a daytime running lamp (DRL), a position lamp, a turn signal lamp, etc.) and a rear combination light. Examples include those used for lights (for example, an appropriate combination of stop lamps, tail lamps, turn signal lamps, back lamps, fog lamps, etc.). However, the applications of the vehicle lighting device 1 are not limited to these.

FIG. 1 is a schematic perspective view for illustrating a vehicle lighting device 1 according to this embodiment.
FIG. 2 is a schematic cross-sectional view of the vehicle lighting device 1 in FIG. 1 taken along the line AA.
As shown in FIGS. 1 and 2, the vehicle lighting device 1 has, for example, a socket 10, a light emitting module 20, and power supply terminals 30. As shown in FIGS.
The socket 10 has, for example, a mounting portion 11, a bayonet 12, a flange 13, heat radiation fins 14, and a connector holder 15. As shown in FIG.

The mounting portion 11 is provided on one surface of the flange 13 (the surface opposite to the side on which the radiation fins 14 are provided). The external shape of the mounting portion 11 can be columnar. The external shape of the mounting portion 11 is, for example, a cylindrical shape. The mounting portion 11 has a concave portion 11a that opens to the end face opposite to the flange 13 side.

A plurality of bayonet 12 are provided on the side surface of the mounting portion 11 . The plurality of bayonet 12 protrudes outward from the vehicle lighting device 1 . A plurality of bayonets 12 are opposed to the flange 13 . The plurality of bayonets 12 are used when the vehicle lighting device 1 is attached to the housing 101 of the vehicle lamp 100 . Multiple bayonets 12 are used for twist locks.

The flange 13 has a plate shape. For example, the flange 13 is disc-shaped. The outer surface of the flange 13 is located outside the vehicle lighting device 1 with respect to the outer surface of the bayonet 12 .

The radiation fins 14 are provided on the side of the flange 13 opposite to the side of the mounting portion 11 . At least one radiation fin 14 can be provided. For example, the socket 10 illustrated in FIGS. 1 and 2 is provided with a plurality of radiating fins 14 . A plurality of radiation fins 14 can be arranged side by side in a predetermined direction. The radiation fins 14 are, for example, plate-shaped.

The connector holder 15 is provided on the side of the flange 13 opposite to the side on which the mounting portion 11 is provided. The connector holder 15 has a tubular shape. A connector 105 having a sealing member 105 a is inserted inside the connector holder 15 . Therefore, the cross-sectional shape and cross-sectional dimensions of the hole of the connector holder 15 are adapted to the cross-sectional shape and cross-sectional dimensions of the connector 105 having the seal member 105a.

Heat generated in the light emitting module 20 is mainly transferred to the heat dissipation fins 14 via the mounting portion 11 and the flange 13 . The heat transferred to the heat radiation fins 14 is mainly released from the heat radiation fins 14 to the outside.
Therefore, considering the transfer of heat generated in the light emitting module 20 to the outside, the socket 10 is preferably made of a material having high thermal conductivity. A material with high thermal conductivity can be, for example, a metal such as an aluminum alloy.

Moreover, in recent years, it is desired that the socket 10 can efficiently dissipate the heat generated in the light emitting module 20 and be lightweight. Therefore, it is more preferable to form the socket 10 from a highly thermally conductive resin. The high thermal conductive resin contains, for example, resin and filler using an inorganic material. The high thermal conductive resin is, for example, a resin such as PET (polyethylene terephthalate) or nylon mixed with a filler using carbon, aluminum oxide, or the like.

If the socket 10 includes a highly thermally conductive resin and the mounting portion 11, the bayonet 12, the flange 13, the heat radiation fins 14, and the connector holder 15 are integrally molded, the heat generated in the light emitting module 20 can be efficiently radiated. can be done. Also, the weight of the socket 10 can be reduced. In this case, the mounting portion 11, the bayonet 12, the flange 13, the heat radiating fins 14, and the connector holder 15 can be integrally molded using an injection molding method or the like. Alternatively, the socket 10 and the power supply portion 30 can be integrally molded using an insert molding method or the like.

The light emitting module 20 has, for example, a substrate 21, a light emitting element 22, and a circuit component 23.

The substrate 21 is provided on one end side of the socket 10 . The substrate 21 can be adhered to the bottom surface 11a1 of the recess 11a, for example. In this case, the adhesive is preferably an adhesive with high thermal conductivity. The adhesive can be, for example, an adhesive mixed with a filler using an inorganic material. The inorganic material is preferably a material with high thermal conductivity (for example, ceramics such as aluminum oxide and aluminum nitride). The thermal conductivity of the adhesive can be, for example, 0.5 W/(m·K) or more and 10 W/(m·K) or less.

Further, a plate-shaped heat transfer portion can be provided between the substrate 21 and the socket 10 . The heat transfer section contains metal such as aluminum, and can be adhered to or embedded in the bottom surface 11a1 of the recess 11a. If a heat transfer section is provided, the substrate 21 is adhered onto the heat transfer section.

The substrate 21 has a plate shape. The planar shape of the substrate 21 is, for example, a quadrangle. The substrate 21 can be made of, for example, an inorganic material such as ceramics (eg, aluminum oxide or aluminum nitride), or an organic material such as paper phenol or glass epoxy. Also, the substrate 21 may be a metal core substrate in which the surface of a metal plate is coated with an insulating material. When the amount of heat generated by the light emitting element 22 is large, it is preferable to form the substrate 21 using a material with high thermal conductivity from the viewpoint of heat dissipation. Examples of materials with high thermal conductivity include ceramics such as aluminum oxide and aluminum nitride, high thermal conductive resins, and metal core substrates. The substrate 21 may have a single layer structure or may have a multilayer structure.

A wiring pattern is provided on the surface of the substrate 21 . The wiring pattern can be formed of, for example, a material containing silver as a main component, a material containing copper as a main component, or the like.

The light emitting element 22 is provided on the substrate 21 . The light emitting element 22 is provided on the side of the substrate 21 opposite to the socket 10 side. The light emitting element 22 is electrically connected to the wiring pattern. A plurality of light emitting elements 22 are provided.
The light emitting element 22 can be, for example, a light emitting diode, an organic light emitting diode, a laser diode, or the like.

The format of the light emitting element 22 is not particularly limited. The light-emitting element 22 can be, for example, a surface-mounted light-emitting element such as a PLCC (Plastic Leaded Chip Carrier) type. The light-emitting element 22 illustrated in FIGS. 1 and 2 is a surface-mounted light-emitting element.
The light-emitting element 22 may be, for example, a bullet-shaped light-emitting element having lead wires.

Also, the light emitting element 22 can be a chip-shaped light emitting element. The chip-shaped light emitting element 22 can be mounted by COB (Chip On Board). The electrodes of the chip-shaped light emitting element 22 are electrically connected to the wiring pattern by wire bonding, for example. Further, when a chip-shaped light emitting element is used, a frame portion surrounding the plurality of light emitting elements 22 and a sealing portion provided inside the frame portion to cover the plurality of light emitting elements 22 can be provided. In addition, the sealing portion can also contain a phosphor as needed.

A circuit component 23 is provided on the substrate 21 . The circuit component 23 is provided, for example, on the side of the substrate 21 opposite to the socket 10 side. The circuit component 23 is electrically connected to, for example, a wiring pattern.
The circuit component 23 can be, for example, a resistor 23a, a protective element 23b, and a controller 23c.

The resistor 23a can be, for example, a surface-mounted resistor, a resistor having lead wires (metal oxide film resistor), or a film resistor formed using a screen printing method or the like. Note that the resistor 23a illustrated in FIG. 1 is a film resistor.

The material of the film resistor is, for example, ruthenium oxide (RuO ₂ ). A film resistor is formed using, for example, a screen printing method and a firing method. If the resistor 23a is a film-shaped resistor, the contact area between the resistor 23a and the substrate 21 can be increased, so heat dissipation can be improved. Also, a plurality of resistors 23a can be formed at once. Therefore, productivity can be improved. In addition, it is possible to suppress variations in resistance values of the plurality of resistors 23a.

Here, since the forward voltage characteristics of the light emitting element 22 vary, if the voltage applied between the anode terminal and the ground terminal is constant, the brightness of the light emitted from the light emitting element 22 (luminous flux, luminance) , luminous intensity, and illuminance). Therefore, the resistor 23a connected in series with the light emitting element 22 keeps the value of the current flowing through the light emitting element 22 within a predetermined range so that the brightness of the light emitted from the light emitting element 22 is within a predetermined range. make it In this case, by changing the resistance value of the resistor 23a, the value of the current flowing through the light emitting element 22 is kept within a predetermined range.

When the resistor 23a is a surface-mounted resistor or a resistor having lead wires, the resistor 23a having an appropriate resistance value is selected according to the forward voltage characteristics of the light emitting element 22. FIG. If the resistor 23a is a film-like resistor, the resistance value can be increased by removing part of the resistor 23a. For example, by irradiating a film resistor with laser light, a part of the film resistor can be easily removed. Note that the number and size of the resistors 23a are not limited to those illustrated, and can be changed as appropriate according to the number and specifications of the light emitting elements 22. FIG.

The protective element 23b can be provided, for example, to prevent reverse voltage from being applied to the light emitting element 22 and to prevent pulse noise from being applied to the light emitting element 22 from the reverse direction. The protective element 23b is, for example, a surface-mounted diode or a diode having a lead wire. The protective element 23b illustrated in FIG. 1 is a surface-mounted diode.

The controller 23c is electrically connected to the multiple light emitting elements 22 . The control unit 23c controls the current flowing through the plurality of light emitting elements 22 when the voltage (input voltage) applied to the vehicle lighting device 1 fluctuates in the operating voltage range (voltage fluctuation range) of the vehicle lighting device 1. suppress fluctuations.
Details of connection between the control unit 23c and the plurality of light emitting elements 22 will be described later.

Also, the circuit component 23 is not limited to the illustrated one. For example, passive elements or active elements used to configure a light emitting circuit having the light emitting element 22 can be appropriately provided as required. For example, the circuit components 23 may include capacitors, pull-down resistors, positive characteristic thermistors, negative characteristic thermistors, inductors, surge absorbers, varistors, transistors such as bipolar transistors and field effect transistors, Zener diodes, integrated circuits, arithmetic It may be an element or the like. The integrated circuit can have, for example, a flashing circuit, a constant current circuit, and/or a lighting circuit (drive circuit). For example, the control unit 23c described above may be an integrated circuit provided with a constant current circuit.

Further, the circuit component 23 can also be provided in, for example, a control device, a power source, or the like provided outside the vehicle lighting device 1 .
In addition, it is also possible to provide a covering portion that covers wiring patterns, film-like resistors, and the like. The cover can include, for example, a glass material.

The power feeding section 30 has, for example, a plurality of power feeding terminals 31 and a holding section 32 .
The plurality of power supply terminals 31 are rod-shaped bodies, for example. A plurality of power supply terminals 31 can be arranged side by side in a predetermined direction. One ends of the plurality of power supply terminals 31 protrude from the bottom surface 11a1 of the recess 11a. One ends of the plurality of power supply terminals 31 are soldered to a wiring pattern provided on the substrate 21 . The other ends of the plurality of power supply terminals 31 are exposed inside the holes of the connector holder 15 . A connector 105 is fitted to the plurality of power supply terminals 31 exposed inside the holes of the connector holder 15 . The plurality of power supply terminals 31 are made of metal such as copper alloy, for example. The shape, arrangement, material, number, etc. of the plurality of power supply terminals 31 are not limited to those illustrated, and can be changed as appropriate.

As previously mentioned, socket 10 is preferably formed from a material with high thermal conductivity. However, materials with high thermal conductivity may have electrical conductivity. For example, metals such as aluminum alloys and highly thermally conductive resins containing carbon-based fillers have electrical conductivity. Therefore, the holding portion 32 is provided to insulate between the plurality of power supply terminals 31 and the conductive socket 10 . The holding portion 32 also has a function of holding the plurality of power supply terminals 31 . Note that if the socket 10 is made of an insulating, highly thermally conductive resin (for example, a highly thermally conductive resin containing a filler using aluminum oxide), the holding portion 32 can be omitted. In this case, the socket 10 holds a plurality of power supply terminals 31 . The holding portion 32 can be made of an insulating resin. For example, the holding portion 32 can be press-fitted into a hole provided in the socket 10 or adhered to the inner wall of the hole.

Next, connection between the control unit 23c and the plurality of light emitting elements 22 will be further described.
First, a light-emitting module 200 according to a comparative example will be described.
3A and 3B are circuit diagrams illustrating a light emitting module 200 according to a comparative example. In addition, in FIGS. 3(a) and 3(b), in order to avoid complication, the above-described protection element 23b and the like are omitted.
3(a) shows the current flow when the input voltage is 10V or more, and FIG. 3(b) shows the current flow when the input voltage is less than 10V.
FIG. 4 is a graph for illustrating the relationship between the input voltage and the total luminous flux in the light emitting module 200 according to the comparative example.

As shown in FIGS. 3A and 3B, the light emitting module 200 is provided with a light emitting circuit 200a, a light emitting circuit 200b, a resistor 223a1, a resistor 223a2, and a controller 223c.
The light emitting circuit 200a has two light emitting elements 22 connected in series.
The light emitting circuit 200 b has one light emitting element 22 .
The light emitting circuit 200a and the light emitting circuit 200b are connected in series.
The resistor 223a1 is connected in series with the light emitting circuit 200b.
The resistor 223a2 is connected in series with the light emitting circuit 200a.
The resistors 223 a 1 and 223 a 2 are provided to adjust variations in forward voltage characteristics of the light emitting element 22 .

Here, although the vehicle lighting device uses a battery as a power source, the voltage (input voltage) applied to the vehicle lighting device fluctuates. For example, the operating standard voltage (rated voltage) of a vehicle lighting device for a general automobile is about 13.5V. However, the input voltage fluctuates due to battery voltage drops, alternator operation, circuit influences, and other factors. Therefore, the operating voltage range (voltage fluctuation range) is defined in the vehicle lighting device for automobiles. For example, the operating voltage range is from 9V to 16V. Note that the operating voltage range may be from 7V to 16V.

Also, the light emitting element 22 has a forward voltage drop. Therefore, when the number of the plurality of light emitting elements 22 connected in series increases, the total luminous flux of the light emitted from the vehicle lighting device 1 may become less than the specified value near the lower limit of the operating voltage range. For example, if the forward voltage drop of the light emitting element 22 is about 3V, connecting three light emitting elements 22 in series results in a voltage drop of 9V. A resistor 223 a 1 is also connected in series to the three light emitting elements 22 . Therefore, when the input voltage is approximately 10 V, almost no current flows through the three light emitting elements 22, and the total luminous flux of the light emitted from the vehicle lighting device becomes less than the specified value.

Therefore, the light emitting module 200 is provided with a control section 223c.
The control unit 223c detects the input voltage, and when the detected input voltage exceeds a predetermined value (for example, when it is 10 V or higher), the series-connected light-emitting circuits 200a and 200b (series-connected A current I1 is passed through the three light emitting elements 22).
Further, when the detected input voltage is less than a predetermined value (for example, less than 10 V), the control unit 223c causes the current I2 to flow only through the light emitting circuit 200a (the two light emitting elements 22 connected in series). . In this way, the current flowing through the two light emitting elements 22 can be increased even if the input voltage becomes less than the predetermined value. Therefore, in the vicinity of the lower limit of the operating voltage range, it is possible to prevent the total luminous flux of the light emitted from the vehicle lighting device from becoming less than the specified value.

However, in this case, when the current I2 is caused to flow only through the light emitting circuit 200a, the current flowing through the two light emitting elements 22 increases sharply. Therefore, as shown in part B of FIG. 4, a new problem arises in that the total luminous flux of the light emitted from the vehicle lighting device sharply increases in the vicinity of the lower limit of the operating voltage range.

FIG. 5 is a circuit diagram illustrating the light emitting module 20 according to this embodiment.
In FIG. 5, in order to avoid complication, the resistor 23a and the protective element 23b are omitted.
As shown in FIG. 5, the light-emitting module 20 includes a light-emitting circuit 20a (corresponding to an example of a first light-emitting circuit), a light-emitting circuit 20b (corresponding to an example of a second light-emitting circuit), and a controller 23c. is provided.

The light emitting circuit 20a and the light emitting circuit 20b are connected in parallel.
The light emitting circuit 20a is provided with a plurality of light emitting elements 22 (corresponding to an example of a first light emitting element) connected in series.
The light emitting circuit 20b is provided with a plurality of light emitting elements 22 (corresponding to an example of a second light emitting element) connected in series.
In this case, the number of light emitting elements 22 provided in the light emitting circuit 20a is greater than the number of light emitting elements 22 provided in the light emitting circuit 20b. For example, the number of light emitting elements 22 provided in the light emitting circuit 20a can be three or more. For example, the number of light emitting elements 22 provided in the light emitting circuit 20b can be two or more. For example, the light emitting circuit 20a illustrated in FIG. 5 is provided with three light emitting elements 22 connected in series, and the light emitting circuit 20b is provided with two light emitting elements 22 connected in series.

The controller 23c is electrically connected to the light emitting circuit 20a and the light emitting circuit 20b. For example, the controller 23c is electrically connected to the anode side of the light emitting element 22 in the light emitting circuit 20a and the anode side of the light emitting element 22 in the light emitting circuit 20b.

As described above, when the voltage (input voltage) applied to the vehicle lighting device 1 fluctuates in the operating voltage range of the vehicle lighting device 1 (for example, 10V to 16V), the control unit 23c controls a plurality of It suppresses the fluctuation of the current flowing through the light emitting element 22 . For example, as shown in FIG. 6, which will be described later, the control unit 23c keeps the current flowing through at least the light emitting circuit 20b approximately constant within the operating voltage range of the vehicle lighting device 1. FIG. The control unit 23c may make the current flowing through the light emitting circuit 20a substantially the same as the current flowing through the light emitting circuit 20b within the operating voltage range of the vehicle lighting device 1 . For example, the controller 23c can have a constant current circuit.

FIG. 6 is a graph for illustrating the relationship between the input voltage and the total luminous flux in light emitting module 20 according to this embodiment.
Note that C in FIG. 6 is the total luminous flux of the light emitted from the light emitting circuit 20a.
D in FIG. 6 is the total luminous flux of light emitted from the light emitting circuit 20b.
E in FIG. 6 is the sum of the total luminous flux of the light emitted from the light emitting circuit 20a and the total luminous flux of the light emitted from the light emitting circuit 20b, that is, the total luminous flux of the light emitted from the vehicle lighting device 1. is.

As described above, the number of light-emitting elements 22 provided in the light-emitting circuit 20a is greater than the number of light-emitting elements 22 provided in the light-emitting circuit 20b, so the voltage drop in the light-emitting circuit 20a is greater than the voltage drop in the light-emitting circuit 20b. growing.

In this case, for example, if the voltage drop in the forward direction of the light emitting element 22 is about 3V, the voltage drop in the light emitting circuit 20a is about 9V, and the voltage drop in the light emitting circuit 20b is about 6V.
Therefore, when the input voltage is close to the lower limit of the operating voltage range (for example, 10 V), almost no current flows through the light emitting circuit 20a, and light is no longer emitted from the light emitting circuit 20a. On the other hand, even when the input voltage is close to the lower limit of the operating voltage range, current flows through the light emitting circuit 20b, so light is emitted from the light emitting circuit 20a.

As described above, the total luminous flux of the light emitted from the vehicle lighting device 1 is the sum of the total luminous flux of the light emitted from the light emitting circuit 20a and the total luminous flux of the light emitted from the light emitting circuit 20b. Therefore, as shown in FIG. 6, even if the lower limit of the operating voltage range (for example, 9 V) is reached, the total luminous flux of the light emitted from the vehicle lighting device 1 is equal to or greater than the specified value.

In the vicinity of the lower limit of the operating voltage range, the total luminous flux of the light emitted from the light emitting circuit 20a gradually decreases substantially in proportion to the decrease in the input voltage. Therefore, as shown in FIG. 6, the total luminous flux of light emitted from the vehicle lighting device 1 gradually decreases near the lower limit of the operating voltage range.
As a result, unlike the light-emitting module 200 according to the comparative example described above, the total luminous flux of light emitted from the vehicle lighting device does not suddenly increase near the lower limit of the operating voltage range.
As described above, with the vehicle lighting device 1 according to the present embodiment, the required total luminous flux can be ensured even when the input voltage is near the lower limit of the operating voltage range, and the operating voltage is low. Abrupt changes in the total luminous flux can be suppressed near the lower limit of the voltage range.

(vehicle lamp)
Next, the vehicle lamp 100 is illustrated.
In the following description, as an example, the case where the vehicle lamp 100 is a front combination light provided in an automobile will be described. However, the vehicle lamp 100 is not limited to a front combination light provided in an automobile. The vehicle lighting device 100 may be a vehicle lighting device provided in an automobile, railroad vehicle, or the like.

FIG. 7 is a schematic partial cross-sectional view for illustrating the vehicle lamp 100. As shown in FIG.
As shown in FIG. 7 , the vehicle lamp 100 includes a vehicle lighting device 1 , a housing 101 , a cover 102 , an optical element 103 and a connector 105 .

The housing 101 holds the mounting portion 11 . The housing 101 has a box shape with one end open. The housing 101 can be made of, for example, a resin that does not transmit light. The bottom surface of the housing 101 is provided with a mounting hole 101a into which a portion of the mounting portion 11 provided with the bayonet 12 is inserted. A recess into which the bayonet 12 provided on the mounting portion 11 is inserted is provided on the periphery of the attachment hole 101a. Although the case where the housing 101 is directly provided with the mounting hole 101a is illustrated, the housing 101 may be provided with a mounting member having the mounting hole 101a.

When the vehicle lighting device 1 is attached to 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, the bayonet 12 is held in the fitting portion provided on the periphery of the mounting hole 101a. Such an attachment method is called a twist lock.

The cover 102 is provided so as to close the opening of the housing 101 . The cover 102 can be made of a translucent resin or the like. The cover 102 can also have a function such as a lens.

Light emitted from the vehicle lighting device 1 enters the optical element 103 . The optical element 103 reflects, diffuses, guides, and collects the light emitted from the vehicle lighting device 1, and forms a predetermined light distribution pattern. For example, optical element 103 illustrated in FIG. 7 is a reflector. In this case, the optical element 103 reflects the light emitted from the vehicle lighting device 1 to form a predetermined light distribution pattern.

The connector 105 is fitted to the ends of the plurality of power supply terminals 31 exposed inside the connector holder 15 . A power source (not shown) is electrically connected to the connector 105 . Therefore, by fitting the connector 105 to the end of the power supply terminal 31, a power source (not shown) and the light emitting element 22 are electrically connected. Further, the connector 105 is provided with a sealing member 105a. The sealing member 105a is provided to prevent water from entering the interior of the connector holder 15. As shown in FIG. When the connector 105 having the seal member 105a is inserted into the connector holder 15, the interior of the connector holder 15 is sealed so as to be watertight.

Although some embodiments of the present invention have been illustrated above, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, changes, etc. can be made without departing from the scope of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention described in the claims and equivalents thereof. Moreover, each of the above-described embodiments can be implemented in combination with each other.

1 Vehicle Lighting Device 10 Socket 20 Light Emitting Module 20a Light Emitting Circuit 20b Light Emitting Circuit 21 Substrate 22 Light Emitting Element 23 Circuit Part 23a Resistor 23b Protection Element 23c Control Unit

Claims (5)

a first light emitting circuit having a plurality of first light emitting elements connected in series;
a second light emitting circuit having a plurality of second light emitting elements connected in series and connected in parallel to the first light emitting circuit;
a controller electrically connected to the first light emitting circuit and the second light emitting circuit;
and
the number of the first light emitting elements is greater than the number of the second light emitting elements,
The control unit is a vehicle lighting device that makes a current flowing through at least the second light emitting circuit substantially constant within an operating voltage range of the vehicle lighting device. 2. The vehicle lighting device according to claim 1, wherein the control unit has a constant current circuit. The number of the first light emitting elements is three or more,
3. The vehicle lighting device according to claim 1, wherein the number of said second light emitting elements is two or more. The vehicle lighting device according to any one of claims 1 to 3, wherein the operating voltage range is from 9V to 16V. A vehicle lighting device according to any one of claims 1 to 4;
a housing to which the vehicle lighting device is attached;
A vehicle lamp equipped with

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