JP2016085788A - Luminaire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a luminaire keeping excellent heat radiation performance of an LED, without impairing a characteristic of an electric component such as an illuminance sensor IC mounted on the same substrate as the LED.SOLUTION: A luminaire comprises: two LEDs 101A, 101B used as a lighting device; an illuminance sensor IC 102A detecting the light and shade of external light; a chip resistance 102B being a peripheral component of the sensor; a chip capacitor 102C; a connector 102D electrically connected an LED drive substrate; a mounting substrate 103 mounted with each components; a heat radiation member 106 directly contacting with the mounting substrate 103 and having four opening parts 104A-104D; and two machine screws 105A, 105B for attaching the mounting substrate 103 to the heat radiation member 106.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an illumination device, and more particularly to an LED illumination device.

  In recent years, lighting devices using LED elements are increasing. Also in surveillance cameras, illumination devices (infrared illumination devices) equipped with LEDs that irradiate light of infrared wavelengths are becoming popular as night vision applications. Although the LED has a characteristic that the light emission efficiency is higher than that of the fluorescent lamp, the lighting device still requires a countermeasure against heat generation. This is especially true when a large amount of electric power is applied to the LEDs to increase the illuminance or a plurality of LEDs are provided in the apparatus.

  Conventionally, as a countermeasure against heat generation, many configurations are known in which heat of an LED is radiated to a metal body (heat sink). Patent Document 1 discloses a configuration in which ceramics are in close contact with a contact portion between a substrate on which an LED is mounted and a metal body (heat sink).

JP 2011-96416 A

  By the way, in an infrared illumination device for a surveillance camera, in order to reduce the number of substrates and reduce costs, not only LEDs but also other electrical components are often mounted on the same substrate. One typical electric component is an illuminance sensor IC. The illuminance sensor IC is provided for the purpose of detecting the brightness of external light in order to determine whether or not to drive the infrared illumination device.

  While the illuminance sensor IC is required to detect minute external light, the illuminance sensor IC has a characteristic that a detection value changes with a change in temperature. Therefore, it is desirable to keep the temperature of the illuminance sensor as constant as possible.

  However, in the configuration in which the metal body (heat sink) is attached to the substrate on which the LED is mounted as disclosed in the above-mentioned patent document, the heat of the LED conducts the metal body, and the heat increases the temperature of the illuminance sensor IC. As a result, there is a problem that the detection value changes.

  Accordingly, an object of the present invention is to provide an illumination device that maintains good heat dissipation of an LED and that does not impair the characteristics of an electrical component such as an illuminance sensor IC mounted on the same substrate as the LED.

In order to achieve the above object, the present invention provides:
At least one optical component that emits light;
At least one electrical component other than the optical component;
A mounting substrate for mounting the optical component and the electrical component;
A heat dissipating means for directly contacting the mounting substrate or indirectly through a heat conducting member to dissipate heat generated from the optical component;
A lighting device having
The heat dissipating means has one or more openings;
At least one of the openings has at least one electrical component in the opening.

  ADVANTAGE OF THE INVENTION According to this invention, provision of the illuminating device which maintains the heat dissipation of LED favorable and does not impair the characteristic of electrical components, such as illumination sensor IC mounted in the same board | substrate as LED, is realizable.

It is a figure which shows the typical structure in connection with embodiment of this invention. It is the figure seen from the mounting board | substrate 103 side when the mounting board | substrate 103 is attached to the heat radiating member 106. FIG. It is a figure which shows the conventional structure. FIG. 4 is a diagram showing a cross section of a dashed line Z part in the configuration of FIG. 3. It is a figure which shows the surface temperature (temperature after saturation) of each component when LED101A and LED101B are driven. FIG. 2 is a view showing a cross section of a dot-dash line Z portion in the configuration of FIG. 1. It is a figure which shows the surface temperature (temperature after saturation) of each component when LED101A and LED101B are driven. It is a figure which shows the typical structure of the surveillance camera provided with the illuminating device.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 8 shows a typical configuration of a surveillance camera provided with a lighting device.

  The surveillance camera provided with the illumination device includes an illumination device 201, a lens unit 202 provided with an image sensor, a drive board 203 for controlling the illumination device 201 and the lens unit 202, an exterior cover 204 for housing them, It comprises a communication cable 205 for connecting to a peripheral device (not shown) such as a recording device. Illumination light from the illumination device 201 is emitted in the optical axis direction of the lens unit 202 as shown in FIG.

  Next, the lighting device 202 will be described along the embodiment of the present invention. FIG. 1 is a diagram showing a typical configuration according to an embodiment of the present invention.

Embodiments of the present invention
Two LEDs 101A, 101B used as illumination,
An illuminance sensor IC 102A for detecting the brightness of external light;
Chip resistors 102B, chip capacitors 102C, which are peripheral components,
A connector 102D for electrically connecting to an LED drive board (not shown);
A mounting board 103 on which the above-described components are mounted;
A heat dissipating member 106 in direct contact with the mounting substrate 103 and having four openings 104A to 104D;
Two screws 105A, 105B for attaching the mounting substrate 103 to the heat dissipation member 106,
Consists of.

  Here, a rigid substrate or a flexible substrate can be used as the mounting substrate 103, but the use of the flexible substrate is more effective for heat dissipation. In addition, the LED 101A, 101B can be applied to either one that emits visible light or one that emits invisible light (infrared light).

  The four openings 104A to 104D in the heat dissipation member 106 will be described with reference to FIG. FIG. 2 is a view seen from the mounting substrate 103 side when the mounting substrate 103 is attached to the heat dissipation member 106. The opening of the heat radiating member 106 is indicated by a dotted line.

  The opening 104A is provided at a position where the screw 105A is attached. The opening 104D is provided at a position where the screw 105B is attached. The opening 104B is provided directly below the connector 102D and has an opening diameter larger than the outer shape of the connector 102D. The opening 104C is provided immediately below the illuminance sensor IC 102A, the chip resistor 102B, and the chip capacitor 102C, and has an opening diameter such that all of these components can be accommodated in the opening.

  Here, FIG. 3 shows a conventional configuration. The point where the opening 104B and the opening 104C do not exist is a difference from FIG. 1 showing a typical configuration according to the embodiment of the present invention.

  FIG. 4 is a view showing a cross-section of the dot-dash line Z portion in the conventional configuration of FIG. The main conduction path of heat when the LED 101A and the LED 101B are driven is indicated by arrows using FIG.

  The four components of the illuminance sensor IC 102A, the chip resistor 102B, the chip capacitor 102C, and the connector 102D are not regarded as heating elements because they generate a small amount of heat. Accordingly, when the two heating elements are the LED 101A and the LED 101B, the heat generated by the LED 101A is conducted to the connector 102D, the illuminance sensor IC 102A, the chip resistor 102B, and the chip capacitor 102C.

  Further, the heat generated in the LED 101B is conducted to the illuminance sensor IC 102A, the chip resistor 102B, and the chip capacitor 102C.

  FIG. 5 shows the surface temperature (temperature after saturation) of each component when LED 101A and LED 101B are driven in a 25 ° C. environment. The LEDs 101A and 101B are 90 ° C., the illuminance sensor IC 102A is 60 ° C., the chip resistor 102B and the chip capacitor 102C are both 70 ° C., and the connector 102D is 75 ° C. Since the temperature of 102A to 102D, which is not regarded as a heating element, is rising, it can be seen that the heat generated in the LEDs 101A and 101B conducts the heat dissipation member 106 to increase the temperature of 102A to 102D. .

  As described above, while the illuminance sensor IC 102A is provided for the purpose of detecting minute external light, it has a characteristic that the detection value changes according to a change in temperature. Therefore, it is desirable to keep the temperature of the illuminance sensor constant. . Similarly, the resistance value and the capacitance value of the chip resistor 102B and the chip capacitor 102C change depending on the temperature. Further, when the temperature rises, the connector 102D is affected by an increase in the contact resistance value. Therefore, it is desirable to take a configuration that keeps the temperature of these electric components 102A to 102D as constant as possible.

  FIG. 6 is a cross-sectional view taken along the alternate long and short dash line Z in the configuration of FIG. 1 according to the embodiment of the present invention. According to FIG. 6, it can be seen that the conduction path shown in FIG. 4 is blocked by the openings 104 </ b> B, 104 </ b> C, and 104 </ b> D provided in the heat radiating member 106. The blocked path is indicated by a broken line.

  Furthermore, FIG. 7 shows the surface temperature (temperature after saturation) of each component when LED 101A and LED 101B are driven in a 25 ° C. environment. Compared with FIG. 5, it turns out that all of 102A-102D have the temperature reduction effect of 20 degreeC.

  As can be seen from the embodiment of the present invention described above, by providing an opening in the heat dissipating member 106 so as to cut off the heat conduction path from the LED, which is a heat generating element, to other electric components, It becomes possible to suppress the influence concerning the temperature rise of components.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

101A, 101B LED, 102A Illuminance sensor IC, 102B Chip resistance,
102C chip capacitor, 102D connector, 103 mounting board,
104A to 104D Opening, 106 Heat dissipation member, 105A, 105B Screw

Claims (3)

At least one optical component that emits light;
At least one electrical component other than the optical component;
A mounting substrate for mounting the optical component and the electrical component;
A heat dissipating means for directly contacting the mounting substrate or indirectly through a heat conducting member to dissipate heat generated from the optical component;
A lighting device having
The heat dissipating means has one or more openings;
At least one of the openings includes at least one electrical component in the opening.   The lighting device according to claim 1, wherein the optical component is mounted on the surface of the mounting substrate using an LED as a light source.   The lighting device according to claim 1, wherein the mounting substrate is a single-sided mounting substrate in which the optical component and the electrical component are mounted on the same surface.