JP2009292311A - Onboard led lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an onboard LED (Light Emitting Diode) lighting system capable of preventing damage of LEDs by fluctuation of DC voltage from an onboard battery. <P>SOLUTION: A panel-shaped lighting unit 4 is provided with a mounting board 6, the plurality of LEDs 8 mounted on one surface of the mounting board 6 and a lighting circuit 10 for turning on the plurality of LEDs 8. The lighting circuit 10 has a voltage control circuit for adjusting DC voltage supplied to each of the plurality of LEDs 8 from the onboard battery to a prescribed voltage value or below and a current control circuit for adjusting DC current supplied to each of the plurality of LEDs 8 from the onboard battery to a prescribed value or below. After DC power from the onboard battery is supplied to the voltage control circuit and the DC voltage is adjusted to the prescribed value or below, the DC power is supplied to the current control circuit and the DC current is adjusted to the prescribed value or below. Subsequently, the DC power is supplied to each of the plurality of LEDs 8. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an in-vehicle LED illumination device for illuminating the interior of a vehicle such as a truck.

  For example, a vehicle-mounted illumination device for illuminating the box-type cargo compartment is provided in a box-type cargo compartment of a vehicle such as a truck (see, for example, Patent Document 1). This in-vehicle illumination device includes a fluorescent lamp, a pair of sockets for holding the fluorescent lamp, and a lighting circuit for lighting the fluorescent lamp. When direct-current power from the in-vehicle battery is supplied to the fluorescent lamp via the lighting circuit, the fluorescent lamp is turned on, and the box-type cargo compartment is illuminated by the light from the fluorescent lamp.

Japanese Utility Model Publication No. 7-37861

  However, the conventional in-vehicle lighting device as described above has the following problems. First, since a fluorescent lamp is used as a light source, if the box-type luggage compartment vibrates when the vehicle is traveling, the filament of the fluorescent lamp may be broken by this vibration, and the box-type luggage compartment is stably illuminated. Can not do it.

  Secondly, the DC voltage from the in-vehicle battery tends to fluctuate. For example, the DC voltage from the in-vehicle battery increases when the vehicle engine is started. When the DC voltage from the in-vehicle battery increases in this way, the DC current flowing through the fluorescent lamp increases, and the fluorescent lamp filament may be broken, and the fluorescent lamp may be damaged.

  An object of the present invention is to provide an in-vehicle LED illumination device that can stably illuminate the interior of a vehicle and can prevent an LED from being damaged by a change in DC voltage from an in-vehicle battery. is there.

The vehicle-mounted LED lighting device according to claim 1 of the present invention is a vehicle-mounted LED lighting device for illuminating a vehicle interior,
A panel-like lighting unit that emits light in a planar shape, the panel-like lighting unit including a mounting board, a plurality of LEDs mounted on one side of the mounting board, and a lighting circuit for lighting the plurality of LEDs With
The lighting circuit includes a voltage control circuit for adjusting a direct current voltage supplied from the in-vehicle battery to each of the plurality of LEDs to a predetermined voltage value or less, and a direct current supplied from the in-vehicle battery to each of the plurality of LEDs. A current control circuit for adjusting the current below a predetermined current value,
The direct current power from the in-vehicle battery is supplied to the voltage control circuit and the direct current voltage is adjusted to the predetermined voltage value or less, and then supplied to the current control circuit to adjust the direct current to the predetermined current value or less. Thereafter, the LED is supplied to each of the plurality of LEDs.

  Moreover, in the vehicle-mounted LED illumination device according to claim 2 of the present invention, the panel illumination unit further includes a light-transmitting cover member that covers one surface of the mounting substrate, and the back surface of the cover member. Are provided with a plurality of first receiving recesses for receiving each of the plurality of LEDs, and diffuses light from the plurality of LEDs into a portion of the cover member corresponding to the plurality of first receiving recesses. A light diffusing means is provided.

  Furthermore, in the vehicle-mounted LED illumination device according to claim 3 of the present invention, the panel illumination unit further includes a support member that supports the mounting substrate, and the cover member is attached to the support member. A dampproofing agent is filled between the outer periphery of the support member and the outer periphery of the cover member.

  In the vehicle-mounted LED lighting device according to claim 4 of the present invention, each of the plurality of first housing recesses is filled with a waterproof mold member, and each of the plurality of LEDs is formed by the waterproof mold member. It is characterized by being covered.

  Furthermore, in the vehicle-mounted LED lighting device according to claim 5 of the present invention, the voltage control circuit and the current control circuit are mounted on one surface of the mounting substrate, and the voltage control circuit is mounted on the back surface of the cover member. And the 2nd accommodation recessed part in which the said current control circuit is accommodated is provided.

  According to the vehicle-mounted LED illumination device of the first aspect of the present invention, since a plurality of LEDs are used as the light source, the interior of the vehicle (for example, a box-type cargo compartment or a driver's compartment) when the vehicle travels. When it vibrates, there is no possibility that the LED is damaged by vibration, and the interior of the vehicle can be stably illuminated. In addition, since the DC power from the in-vehicle battery is supplied to the voltage control circuit and the DC voltage is adjusted to a predetermined voltage value or less, the DC power is supplied to the current control circuit and the DC current is adjusted to a predetermined current value or less. Even when the DC voltage from the in-vehicle battery fluctuates, it is possible to prevent an excessive DC voltage or DC current from being supplied to each LED and to prevent the LED from being damaged.

  Moreover, according to the vehicle-mounted LED illumination device according to claim 2 of the present invention, since the plurality of first housing recesses are provided on the back surface of the cover member, the LED is provided in each of the plurality of first housing recesses. Is housed, the entire panel illumination unit can be made thinner by the thickness of the LED. Therefore, the space for attaching the panel-like lighting unit to the interior of the vehicle can be kept small, and the panel-like lighting unit can be easily attached. Further, since the light diffusing means is provided at the portion of the cover member corresponding to the plurality of first receiving recesses, the light from the LED is diffused by the light diffusing means so that the interior of the vehicle can be efficiently illuminated. it can.

  Furthermore, according to the vehicle-mounted LED lighting device according to claim 3 of the present invention, the moisture-proofing agent is filled between the outer peripheral portion of the support member and the outer peripheral portion of the cover member. Moisture generated by condensation can be absorbed by the moisture-proofing agent, and moisture can be prevented from entering the panel-like lighting unit.

  Moreover, according to the vehicle-mounted LED illumination device according to claim 4 of the present invention, since each of the plurality of LEDs is covered with the waterproof mold member, moisture generated by dew condensation in the vehicle interior is assumed to be in the form of a panel. Even when the light enters the lighting unit, moisture does not adhere to the lead portion of the LED, and a short circuit of the lighting circuit or the like can be prevented.

  Furthermore, according to the vehicle-mounted LED lighting device according to claim 5 of the present invention, since the second housing recess is provided on the back surface of the cover member, the cover housing is mounted on one surface of the mounting substrate. By accommodating the voltage control circuit and the current control circuit, the entire panel illumination unit can be made thinner by the thickness of the voltage control circuit and the current control circuit. Therefore, the space for attaching the panel-like lighting unit to the interior of the vehicle can be kept small, and the panel-like lighting unit can be easily attached.

  Hereinafter, an embodiment of an in-vehicle LED lighting device according to the present invention will be described with reference to the accompanying drawings. FIG. 1 is a perspective view showing a panel-like illumination unit of an in-vehicle LED illumination device according to an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view of the panel-like illumination unit taken along line AA in FIG. FIG. 3 is a schematic cross-sectional view of the panel-like lighting unit taken along the line BB in FIG. 1, and FIG. 4A is a schematic plan view showing the first housing recess in FIG. 1 in an enlarged manner. 4B is an enlarged schematic cross-sectional view showing the first housing recess of FIG. 1, and FIG. 5 is a circuit block diagram schematically showing the lighting circuit of the panel illumination unit of FIG. .

  Referring to FIGS. 1 to 5, the in-vehicle LED lighting device 2 includes a rectangular panel-shaped lighting unit 4 that emits light in a planar shape. The panel-shaped lighting unit 4 is, for example, a truck. It is installed in a box-type luggage compartment (not shown) of the vehicle. The panel illumination unit 4 includes a mounting board 6, a plurality of LEDs 8 mounted on one side of the mounting board 6, a lighting circuit 10 for lighting the plurality of LEDs 8, and a support member 12 for supporting the mounting board 6. And a cover member 14 that covers one surface of the mounting substrate 6. Hereinafter, the configuration of the panel illumination unit 4 will be described in detail.

  The mounting substrate 6 is configured in a rectangular shape and a thin plate shape, and a wiring pattern (not shown) is provided on one surface thereof. The mounting substrate 6 is provided with a plurality of insertion holes 18 through which the fixing screws 16 are inserted. The LED 8 is composed of, for example, a chip-type high-intensity LED, and includes a light emitting unit 20 and a pair of lead portions (not shown) extending from the light emitting unit 20. The pair of lead portions of the LED 8 are electrically connected to the wiring pattern of the mounting substrate 6 by soldering. In the present embodiment, the plurality of LEDs 8 have first to fourth LED groups 22 to 28 electrically connected in parallel, and each of the first to fourth LED groups 22 to 28 is electrically connected in series. It consists of only one resistive element 30 and seven LEDs 8 (see FIG. 5).

  The lighting circuit 10 includes a voltage control circuit 32 and a current control circuit 34 mounted on one side of the mounting substrate 6 (see FIG. 5). The voltage control circuit 32 includes a switching element 36 such as a transistor, a resistance element 38, and a Zener diode 40. A DC voltage supplied to each of the plurality of LEDs 8 from a vehicle-mounted battery 42 mounted on the vehicle is set to a predetermined voltage value (for example, Adjust to about 27V or less. The current control circuit 34 includes two switching elements 44 and 46 and five resistance elements 48 to 56, and a direct current supplied from the in-vehicle battery 42 to each of the plurality of LEDs 8 is set to a predetermined current value (for example, about 60 mA). ) Adjust to the following. The plurality of electronic components 58 constituting the voltage control circuit 32 and the current control circuit 34 are electrically connected to the wiring pattern of the mounting substrate 6 by soldering. The lighting circuit 10 is disposed between the in-vehicle battery 42 and the first to fourth LED groups 22 to 28, and the lighting circuit 10 and the in-vehicle battery 42 are electrically connected via a power cable 60 extending from the mounting substrate 6. It is connected. The in-vehicle battery 42 is electrically connected to the input side of the voltage control circuit 32, the input side of the current control circuit 34 is electrically connected to the output side thereof, and the first side is connected to the output side of the current control circuit 34. -4th LED group 22-28 is electrically connected.

  The support member 12 is formed in a plate shape, and an engagement protrusion 62 extending in a predetermined direction (that is, the direction in which the cover member 14 is disposed) is provided on the outer peripheral portion thereof. The mounting substrate 6 is supported on one side of the support member 12. Further, the support member 12 is provided with a plurality of screw holes 64 corresponding to the plurality of insertion holes 18 of the mounting substrate 6, and a power cable 60 extending from the mounting substrate 6 is inserted into the engaging protrusion 62. A notch (not shown) is provided.

  The cover member 14 is made of a translucent acrylic resin or polycarbonate resin. The cover member 14 is provided with a plurality of insertion holes 66 corresponding to the plurality of insertion holes 18 of the mounting substrate 6. An engagement recess 68 extending in a direction opposite to the predetermined direction (that is, the direction in which the support member 12 is disposed) is provided on the outer peripheral portion of the cover member 14, and the notch of the support member 12 is provided in the engagement recess 68. A notch 70 is provided correspondingly. On the back surface of the cover member 14, a plurality of circular first housing recesses 72 corresponding to the plurality of LEDs 8 and a plurality of rectangular shapes corresponding to the plurality of electronic components 58 are provided. 2nd accommodation recessed part 74 is provided. An uneven portion 76 (which constitutes a light diffusing means) is formed in a portion corresponding to the first receiving recess 72 on the back surface side of the cover member 14, and the uneven portion 76 includes a plurality of adjacently disposed plural portions. It is comprised from the peak part 78 and the trough part 80 (refer FIG. 4). Each of the first and second receiving recesses 72 and 74 is filled with a waterproof mold member (not shown) made of, for example, a transparent silicon resin.

  The engagement protrusion 62 of the support member 12 and the engagement recess 68 of the cover member 14 are engaged with each other, and the fixing screw 16 passes through the insertion hole 66 of the cover member 14 and the insertion hole 18 of the mounting substrate 6. The cover member 14 is attached to the support member 12 by being screwed into the screw hole 64. When attached in this way, one surface of the mounting substrate 6 is covered with the cover member 14, each light emitting part 20 of the plurality of LEDs 8 is housed in the plurality of first housing recesses 72, and a plurality of electronic components 58 are respectively disposed. It accommodates in the some 2nd accommodation recessed part 74 (refer FIG.2 and FIG.3). Thereby, LED8 and the electronic component 58 are each covered with the waterproof mold member. Further, the power cable 60 extending from the mounting substrate 6 extends to the outside through the notch of the support member 12 and the notch 70 of the cover member 14. A gap between the engagement protrusion 62 and the engagement recess 68 is filled with a moisture-proofing agent (not shown) such as silica gel.

  Illumination by the vehicle-mounted LED illumination device 2 described above will be described as follows. The in-vehicle battery 42 is configured to output DC power of about 24V, for example. When DC power from the in-vehicle battery 42 is supplied to the voltage control circuit 32 via the power cable 60, the DC voltage is adjusted to be equal to or lower than the predetermined voltage value in the voltage control circuit 32 by the action of the Zener diode 40. For example, when the DC voltage supplied to the voltage control circuit 32 is lower than the predetermined voltage value of 27V (for example, 20V), a DC voltage having the same voltage value as the supplied voltage value is output. When the DC voltage supplied to is higher than 27V (for example, 36V), the DC voltage is adjusted to 27V and output.

  When the DC power output from the voltage control circuit 32 is supplied to the current control circuit 34, the DC current is adjusted below the predetermined current value in the current control circuit 34 by the on / off operation of the switching elements 44 and 46. Is done. For example, when the direct current supplied to the current control circuit 34 is smaller than the predetermined current value of 60 mA (for example, 50 mA), the switching element 44 is turned on and the switching element 46 is turned off. When a direct current having the same current value is output and the direct current supplied to the current control circuit 34 is larger than 60 mA (for example, 70 mA), the switching element 44 is turned off and the switching element 46 is turned on. Is adjusted to 60 mA and output.

  The DC power output from the current control circuit 34 is supplied to each LED 8, thereby turning on each LED 8. The light from the LED 8 passes through the cover member 14 and is irradiated to the outside. As a result, light is emitted in a planar shape over almost the entire area of the cover member 14 to illuminate the box-type cargo compartment.

  In the vehicle-mounted LED lighting device 2 of the present embodiment, the following operational effects are achieved. First, when starting an engine mounted on a vehicle or using an air conditioner, the DC voltage from the in-vehicle battery 42 tends to fluctuate within a range of 18 to 36 V, for example. As described above, the DC voltage supplied to each LED 8 is adjusted to be equal to or lower than the predetermined voltage value, and the DC current flowing through each LED 8 is equal to or lower than the predetermined current value. Adjusted to. Therefore, it is possible to prevent an excessive direct current voltage or direct current from being supplied to each LED 8, and it is possible to prevent the LED 8 from being damaged.

  Secondly, since the light from the LED 8 is diffused by the concavo-convex portion 76 of the cover member 14, the light from the plurality of LEDs 8 is diffused and irradiated into the box-type luggage compartment, thereby efficiently illuminating the box-type luggage compartment. Can do.

  Third, each light emitting unit 20 of the plurality of LEDs 8 is housed in the plurality of first housing recesses 72, and the plurality of electronic components 58 are housed in the plurality of second housing recesses 74, respectively. The entire panel-like lighting unit 4 can be reduced in thickness by the thickness of the light emitting unit 20 and the thickness of the electronic component 58. Therefore, the space for mounting the panel-shaped lighting unit 4 in the box-type cargo compartment of the vehicle can be kept small, and the panel-shaped lighting unit 4 can be easily mounted.

  Fourth, since a moisture proofing agent is filled in the gap between the engagement protrusion 62 and the engagement recess 68, for example, moisture generated by condensation in the box-type cargo compartment can be absorbed by the moisture proofing agent. It is possible to prevent moisture from entering the panel illumination unit 4. In addition, since the LED 8 and the electronic component 58 are each covered with a waterproof mold member, even if moisture enters the inside of the panel-like lighting unit 4, the moisture is in the lead portion of the LED 8 and the electronic component 58. It is possible to prevent the lighting circuit 10 and the like from being short-circuited without being attached. Instead of the moisture-proof agent, a waterproof seal member such as silicon rubber is interposed in the gap between the engagement protrusion 62 and the engagement recess 68, and the gap is sealed by the waterproof seal member. It may be.

  Next, with reference to FIG. 6, another embodiment of the in-vehicle LED lighting device will be described. FIG. 6 is a perspective view showing a panel illumination unit of an in-vehicle LED illumination device according to another embodiment of the present invention. In this other embodiment, components that are substantially the same as those of the above-described embodiment are given the same reference numerals, and descriptions thereof are omitted.

  In the vehicle-mounted LED lighting device 2A according to another embodiment, the panel-shaped lighting unit 4A is formed in a circular shape. A plurality of concentrically arranged LEDs 8 are mounted on one side of the circular and thin mounting board 6A, and a voltage control circuit (not shown) and a current control circuit (not shown) are mounted at the center. A plurality of electronic components 58 constituting the device are mounted. On the back surface of the cover member 14 </ b> A, a plurality of circular first receiving recesses 72 </ b> A disposed corresponding to the plurality of LEDs 8, and a circular first corresponding to the plurality of electronic components 58. 2 accommodating recesses 74A are provided. Further, an uneven portion (not shown) (which constitutes a light diffusing means) is formed in a portion corresponding to the first accommodating recess 72A on the back surface side of the cover member 14A, and this uneven portion is a blast having fine unevenness. Configured. In the in-vehicle LED lighting device 2A of the present embodiment, the same effects as those of the above-described embodiment are achieved.

  As mentioned above, although the embodiment of various vehicle-mounted LED lighting devices according to the present invention has been described, the present invention is not limited to such an embodiment, and various modifications and corrections can be made without departing from the scope of the present invention. It is.

  For example, the light diffusing means for diffusing the light from the plurality of LEDs 8 may be constituted by the uneven portion 76 having a plurality of peak portions 78 and valley portions 80 arranged in a lattice shape, a concentric circle shape, or a spiral shape. Good. Or you may comprise from the diffusion sheet attached to the site | part corresponding to the 1st accommodating recessed part 72 (72A) of the back surface side of the cover member 14 (14A).

Further, for example, in each of the above embodiments, the uneven portion 76 is formed on the back surface side of the cover member 14 (14A), but the uneven portion 76 may be formed on the front surface side of the cover member 14 (14A).
Further, for example, in each of the embodiments described above, the panel-like lighting unit 4 (4A) is attached to the box-type cargo compartment of the vehicle, but may be attached to the cab of the vehicle.

It is a perspective view which shows the panel-shaped illumination unit of the vehicle-mounted LED illuminating device by one Embodiment of this invention. It is a schematic sectional drawing of the panel-shaped illumination unit by the AA line in FIG. It is a schematic sectional drawing of the panel-shaped illumination unit by the BB line in FIG. (A) is a schematic plan view which expands and shows the 1st accommodation recessed part of FIG. 1, (b) is a schematic sectional drawing which expands and shows the 1st accommodation recessed part of FIG. It is a circuit block diagram which shows simply the lighting circuit of the panel-shaped illumination unit of FIG. It is a perspective view which shows the panel-shaped illumination unit of the vehicle-mounted LED illuminating device by other embodiment of this invention.

Explanation of symbols

2,2A In-vehicle LED lighting device 4,4A Panel illumination unit 6,6A Mounting board 8 LED
DESCRIPTION OF SYMBOLS 10 Lighting circuit 14,14A Cover member 32 Voltage control circuit 34 Current control circuit 42 Car-mounted battery 72,72A 1st accommodation recessed part 74,74A 2nd accommodation recessed part 76 Irregularity part

Claims (5)

An in-vehicle LED lighting device for illuminating the interior of a vehicle,
A panel-like lighting unit that emits light in a planar shape, the panel-like lighting unit including a mounting board, a plurality of LEDs mounted on one side of the mounting board, and a lighting circuit for lighting the plurality of LEDs With
The lighting circuit includes a voltage control circuit for adjusting a direct current voltage supplied from the in-vehicle battery to each of the plurality of LEDs to a predetermined voltage value or less, and a direct current supplied from the in-vehicle battery to each of the plurality of LEDs. A current control circuit for adjusting the current below a predetermined current value,
The direct current power from the in-vehicle battery is supplied to the voltage control circuit and the direct current voltage is adjusted to the predetermined voltage value or less, and then supplied to the current control circuit to adjust the direct current to the predetermined current value or less. Thereafter, the vehicle-mounted LED lighting device is supplied to each of the plurality of LEDs.   The panel-like lighting unit further includes a light-transmitting cover member that covers one surface of the mounting substrate, and a plurality of first housings in which each of the plurality of LEDs is housed on the back surface of the cover member. The light-diffusion means for diffusing the light from these LED is provided in the site | part corresponding to the said some 1st accommodation recessed part of the said cover member provided with the recessed part, The light-diffusion means for diffusing the light from these LED is provided. The vehicle-mounted LED illumination device according to 1.   The panel-like lighting unit further includes a support member that supports the mounting substrate, and the cover member is attached to the support member, and is between the outer peripheral portion of the support member and the outer peripheral portion of the cover member. The in-vehicle LED lighting device according to claim 2, which is filled with a moisture-proofing agent.   4. The vehicle-mounted device according to claim 2, wherein each of the plurality of first housing recesses is filled with a waterproof mold member, and each of the plurality of LEDs is covered with the waterproof mold member. LED lighting device.   The voltage control circuit and the current control circuit are mounted on one surface of the mounting substrate, and a second housing recess for housing the voltage control circuit and the current control circuit is provided on the back surface of the cover member. The in-vehicle LED lighting device according to any one of claims 2 to 4.

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