JP6116049B2 - Light emitting diode projector - Google Patents

Description

  The present invention relates to a light emitting diode projector using a light emitting diode element as a light source. In particular, the present invention relates to a large projector that has a relatively large amount of light used outdoors.

  In recent years, with the progress of technology for obtaining white light with a light-emitting diode element, the conversion from an illumination lamp such as an incandescent lamp, a fluorescent lamp, and a mercury lamp to a light-emitting diode-type illumination lamp is rapidly progressing. And light-emitting diode elements are mainly used in place of mercury lamps as light sources for large floodlights with a relatively large amount of light that are used for night lighting, garden lighting, or signage lighting for tennis courts and sports fields. It is getting used. Hereinafter, in the present invention, a semiconductor chip of a light emitting diode including electrodes is referred to as a light emitting diode element (LED).

  If the irradiation distance which is the same as the mercury lamp projector is obtained for the LED projector, the amount of heat generated by the LED exceeds the allowable amount. Therefore, the light projector is provided with a heat sink having flat fins that can increase the blade area. However, in a projector having a large amount of light where the temperature of the LED of the light source is too high to touch, the energy loss cannot be sufficiently reduced only by using a large heat sink, and the LED is still damaged. There is a fear.

  It is possible to increase the heat dissipation effect by increasing the volume of the heat sink body and increasing the total number of fins by increasing the number of flat fins. However, if the heat sink body is too large, the mass of the heat sink increases and the total weight of the projector increases. Further, in the metal integral molding process, it is difficult to add a sufficient number of thin plate-shaped fins having a larger blade area.

  If a cooling device that forcibly cools, such as a blower fan or a water cooling device, is provided, the number of parts increases and the structure of the projector becomes more delicate. Therefore, productivity is reduced. In addition, in an outdoor lighting facility that is exposed to direct sunlight and wind, snow and rain, a projector equipped with a cooling device is more easily damaged. As a result, compared to a projector using a so-called light bulb as a light source such as a mercury lamp projector that does not require a cooling device, the burden of work and cost required for equipment and maintenance by installation, inspection, repair, or replacement is greater. .

  For example, as shown in Patent Document 1, a Peltier element is provided between a heat sink body provided with a cooling medium in a hollow space and a plurality of heat radiation fins provided on a lower surface of a substrate on which a plurality of LEDs are arranged. A light emitting diode module is known. Although the Peltier element cannot be said that the cooling efficiency is so excellent in principle, there is an advantage that the cooling device can be made relatively small. Further, the structure of the cooling device is relatively simple.

JP 2008-53724 A

  Since the Peltier element is configured to absorb heat from the absorption side, transfer heat to the exhaust heat side, and exhaust heat from the exhaust heat side, cooling efficiency cannot be improved unless the Peltier element is effectively cooled. In particular, if heat is accumulated without being sufficiently radiated, the Peltier element itself may be burned out. Therefore, when a Peltier element is used as a cooling device for a projector used outdoors, the cooling device is still likely to fail.

  In view of the above problems, an object of the present invention is to provide an LED projector having a heat sink that has a relatively simple configuration and can radiate heat more efficiently. The advantages of the present invention will be shown each time in the description of specific embodiments of the invention.

In order to solve the above problems, the projector according to the present invention is configured such that a substrate (3) on which a plurality of light emitting diode elements (2) as light sources are disposed, and a hole-shaped space is formed inside. A base (61) for tightly fixing the substrate (3) to the surface where the space is not formed, and a base (61) fixed to the base (61) so as to cover the space with a lid are in close contact with the base (61). A main body (6A) composed of a vibrating body (62) in which a plurality of linear grooves are formed in parallel on the surface opposite to the surface to be fixed, and a thin plate formed at a predetermined minimum interval. A plurality of fins (6B) that are respectively fitted in a plurality of straight grooves formed on the vibrator (62) of the main body (6A) so as to be parallel to each other, and a base (61 of the main body (6A)) ) and vibration in the space formed between the vibrator (62) A square plate shape or a disc shape of the ultrasonic transducer vibrates the body (62) fins are provided so as to be in contact with (6B) (6C), the heat sink (6) made of, is to have.

  In the projector, the ultrasonic transducer (6C) is preferably provided between the base (61) and the vibrating body (62). In addition, the code | symbol described in the said parenthesis attaches | subjects the code | symbol provided in drawing so that drawing can be referred for convenience of explanation, Comprising: This invention is shown concretely in drawing However, the present invention is not limited to such an embodiment.

  The projector of the present invention imparts minute vibrations to a thin flat fin by an ultrasonic vibrator. In a space formed between fins adjacent to each other provided in parallel to each other, air whose temperature has risen due to heat dissipation is swept by the vibrating fins and convection is promoted. Therefore, the air in the space is circulated, the heat dissipation effect is improved, and the temperature of the substrate can be maintained at a predetermined temperature or lower. As a result, the burden of work and costs required for equipment and maintenance is reduced.

It is side surface sectional drawing which shows the projector of embodiment of this invention. It is a front view of the state which removed the reflector of the projector of an embodiment. It is a perspective view which shows the light projector of this invention.

  1 to 3 show an embodiment of a projector according to the present invention. In the present invention, as shown in FIG. 1, a linear direction in which a projector is installed to irradiate light is defined as an irradiation direction Dx. And the surface which goes to the irradiation direction Dx is made into the front surface or front surface of a projector, and the opposite surface of a front surface is made into a back surface or a back surface. Further, the right side is the right side, the left side is the left side, the upper side is the upper side, and the lower side is the lower side with respect to the irradiation direction Dx. The direction from the rear surface to the front surface along the irradiation direction Dx will be described as the front-rear direction, the direction from the upper surface to the lower surface as the vertical direction or the vertical direction, and the directions of the left and right side surfaces as the horizontal direction or the horizontal direction.

  As shown in FIGS. 1 to 3, the LED projector includes a projector main body 1, a plurality of light emitting diode elements (LEDs) 2 that are light sources provided in the projector main body 1, and a substrate on which a plurality of LEDs 2 are disposed. 3, a support 4 that supports the projector main body 1, a reflector 5 that is provided so as to surround the LED 2 of the light source, and a substrate 3 that is provided in the projector main body 1 so as to be in contact with the entire surface of the substrate 3. And a heat sink 6.

  The plurality of LEDs 2 are supplied with electric power from a DC power source (not shown) provided far away from the projector main body 1. For example, an input terminal is provided on the lower side of the projector main body 1, and a cable is connected between the input terminal and the DC power source. Since the distance between the projector main body 1 and the DC power supply is limited, depending on the scale of the facility, the plurality of projectors can be supplied with power from the plurality of DC power supplies.

  The plurality of LEDs 2 are electrically connected in series in units of several to a dozen. A series unit composed of a plurality of LEDs 2 connected in series is connected in parallel. The substrate 3 is provided with the number of the light quantity with a margin so that the maximum light quantity that can be obtained when the rated maximum current value is supplied from the DC power supply sufficiently exceeds the required light quantity. Even if the LED 2 is damaged and the series unit is electrically disconnected, it is possible to continue irradiating with a required amount of light.

  The substrate 3 is made of a metal with good heat conductivity. Therefore, the substrate 3 absorbs heat generated from the LEDs 2 in a short time. Specifically, the substrate 3 is made of copper. A printed circuit board (not shown) is provided adjacent to the substrate 3 and supplies current to the substrate 3 through the printed circuit board. The substrate 3 is fixed so that the entire back surface where the LED 2 is not disposed is in close contact with the heat sink 6 with a flexible heat transfer body such as silicon grease or graphite sheet interposed therebetween. Therefore, the heat generated by the LED 2 is quickly transmitted to the heat sink 6 through the substrate 3.

  The projector main body 1 is installed by a support 4 on an illumination tower of an illumination facility or an illumination stand of an illumination column. The support 4 is manufactured by bending both sides of a highly rigid metal sheet metal such as iron. The support body 4 has a strength that can withstand the load of the projector main body 1 including the mounting metal and the bolts that are fixed to the illumination base. For example, the support body 4 has such a strength that it does not break immediately even when the floodlight body 1 is subjected to a predictable strong wind load at a high place.

  Mounting holes are provided at two locations in the intermediate portion sandwiched between both ends of the support 4 where the sheet metal is bent. One attachment hole is an arc-shaped long hole. By aligning the position of the mounting hole of the support 4 and the position of the mounting hole provided on the side of the illumination stand and completely fixing the projector body 1 through a bolt to one of the mounting holes, the projector is installed in the lighting equipment. .

  As shown in FIG. 1, the reflector 5 is entirely attached and fixed to a heat sink body 6 </ b> A of the heat sink 6 so that at least a part of the inner cylinder end contacts the surface of the copper substrate 3. It can also be fixed so that the inner cylinder end of the reflector 5 is in contact with the main body 6A. The reflector 5 of the projector according to the embodiment has a role of a heat radiating plate that radiates heat generated from the LED 2 by the reflector 5 being in contact with the surface of the copper substrate 3. Therefore, the projector according to the embodiment has an advantage that the heat dissipation effect is further improved.

  The reflector 5 is a reflecting tube for condensing the light from the LED 2 serving as a light source and applying light to a predetermined irradiation range required in advance according to a predetermined irradiation distance. The inside of the reflector 5 is formed of a plurality of metal flat plates. The reflection surface is an entirely smooth surface so as not to scatter the reflected light as much as possible, and is coated with a reflection material having a high reflectance. The reflector 5 of the projector according to the embodiment is formed of an aluminum plate in which fine metal particles capable of forming a reflective surface such as aluminum, silver, and titanium oxide are uniformly deposited on the inner surface.

  In the reflector 5, at least the front shape of the opening 5 </ b> A is a square shape. In the reflector 5 of the projector according to the embodiment, the step surface in the direction perpendicular to the irradiation direction Dx has a quadrangular shape. The shape of the boundary of the light irradiated on the flat irradiation surface is a shape obtained by projecting the opening 5A according to a predetermined irradiation angle. Therefore, when the irradiation surface to be irradiated is a flat surface, the shape of the predetermined irradiation range is approximately a trapezoid. The irradiation angle is an angle formed by the irradiation direction Dx with respect to a flat irradiation surface.

  The central region of the irradiation region is irradiated with light that directly hits the irradiation surface without being reflected by the reflection surface of the reflector 5 from the LED 2 of the light source and reflected light that is reflected by the reflection surface. On the other hand, in a region at the outer edge of the predetermined irradiation region, light having a relatively long distance hits the light directly hitting the irradiation surface without being reflected from the reflection surface of the reflector 5 from the LED 2. Therefore, the brightness in the outer edge region is darker than the brightness in the central region. Therefore, strong light does not strike beyond a predetermined irradiation range.

  Specifically, the reflector 5 includes a condensing part 5B and an irradiation part 5C. The condensing part 5B has a role which mainly condenses the light of LED2 which is a light source. The inner reflecting surface, which is the inner surface of the condensing portion 5B, expands in all directions toward the outside at the first angle α with respect to the irradiation direction Dx. The irradiation part 5C has a role of applying light to a predetermined irradiation range mainly in accordance with a predetermined irradiation distance. The inner reflective surface of the irradiated portion 5C expands outward in all directions at a second angle β smaller than the first angle α with respect to the irradiation direction Dx.

  The condensing part 5B is located in the reflector 5 at a place closer to the LED 2 of the light source than the irradiation part 5C. The irradiation part 5C is located in the reflector 5 at a position closer to the opening 5A than the condensing part 5B. The irradiation part 5C is connected to the condensing part 5B. The cross-sectional shape of the frontage at the position where the condensing part 5B and the irradiation part 5C are connected is a quadrangular shape similar to the cross-sectional shape of the opening 5A.

  The heat sink 6 includes a heat sink main body 6A including a heat sink base 61 for fixing the substrate 3 in close contact and a heat sink vibrating body 62 fixed to the heat sink base 61, a plurality of thin flat plate-like fins 6B provided on the main body 6A, and the main body 6A. And an ultrasonic transducer 6C that applies vibration to the plurality of fins 6B. In particular, in the heat sink 6 of the projector according to the embodiment, a hollow space is provided in the main body 6A in order to reduce the mass of the heat sink 6. Specifically, the main body 6 </ b> A includes a heat sink base 61 and a heat sink vibrating body 62, and a hollow space is formed between the base 61 and the vibrating body 62.

  The heat sink base 61 fixes the copper substrate 3 provided with the LEDs 2 so that the entire surface of the substrate 3 is in close contact. The base body 61 is a box that is configured such that a space is formed inside by combining an aluminum casting body in which a hole-shaped space is formed or a plurality of aluminum plates. The substrate 3 is provided on the surface of the base 61 where the space is not formed. The heat sink vibrating body 62 is fixed to the base body 61. The heat sink vibrating body 62 is made of aluminum, and is fixed to the base 61 so as to cover and close the space. As a result, a hollow space is formed in the main body 6 </ b> A composed of the base body 61 and the vibrating body 62.

  The fin 6B is formed of a thin aluminum plate. The plurality of fins 6B are provided on the heat sink body 6A so as to be parallel to each other at a predetermined interval as small as possible. Desirably, the plurality of fins 6B are provided in a direction in which a space formed by adjacent fins 6B (hereinafter referred to as a heat radiation space) is opened upward in accordance with a posture in which the projector main body 1 is attached to the illumination base. In the projector according to the embodiment, it is assumed that the irradiation surface is irradiated downward at a predetermined irradiation angle, and the plurality of fins 6B are open to the outside on the rear surface of the projector main body 1 with respect to the main body 6A. And are provided so as to protrude vertically.

  In the heat sink body 6A, a plurality of straight grooves for attaching and fixing the fins 6B to the surface opposite to the surface (the rear surface side) with respect to the surface to which the substrate 3 is closely fixed are formed in parallel. In particular, in the heat sink 6 of the projector according to the embodiment, the heat sink vibrating body 62 is provided with a plurality of grooves. The plurality of grooves are formed by cutting. Then, the plurality of fins 6B are fitted into the respective grooves and fixed to the main body 6A by welding with a metal made of heat conduction or adhesion with an adhesive having high thermal conductivity.

  Therefore, the heat sink 6 can increase the blade area of the fin 6B and reduce the thickness. Moreover, the attachment cost for attaching the fin 6B to the heat sink main body 6A is unnecessary. Moreover, the predetermined space | interval of adjacent fin 6B can be made smaller. Therefore, a larger number of fins 6B can be provided, and an increase in the mass of the heat sink 6 relative to the heat dissipation effect can be minimized. And since the thin flat fin 6B is flat on the whole surface, it can obtain a sufficient heat dissipation effect without hindering smooth flow in the heat dissipation space.

  In order to increase the heat radiation amount per unit time, as many fins 6B as possible should be provided. However, if the interval between the adjacent fins 6B is too small, the air flow in the heat dissipation space is deteriorated. As a result, the air heated by heat dissipation stays in the heat dissipation space and is not easily exchanged with outside air having a low temperature, and the heat dissipation effect is reduced. Therefore, basically, the predetermined interval at which the plurality of fins 6B are arranged depends on the installation location of the projector, and at least the length necessary for at least warmed air to be quickly discharged from the heat dissipation space. Also long.

  The thin aluminum fin 6B has small rigidity and is easy to bend. If the fins 6B are bent, the heat dissipation space may be blocked by the bent fins 6B and the air fluidity may be reduced. Therefore, it is desirable to provide a reinforcing member 7 that fixes and supports the opposite edges of the plurality of fins 6B and the heat sink body 6A. The reinforcing material 7 prevents the fins 6B from dropping off from the main body 6A at the same time.

  The ultrasonic transducer 6C is means for vibrating the fin 6B. The ultrasonic transducer 6C is provided substantially in the heat sink 6A. More specifically, the ultrasonic transducer 6 </ b> C is provided between the heat sink base 61 and the vibrating body 62 so as to be accommodated in a mounting space formed in the heat sink vibrating body 61. A plurality of ultrasonic transducers 6C can be provided as shown in FIG. The ultrasonic vibrator 6 </ b> C is provided so as to come into contact with the vibrating body 62 within a range in which the efficiency of heat conduction between the base 61 and the vibrating body 62 is not significantly reduced.

  When a high-frequency current is supplied from a lead wire (not shown), the ultrasonic transducer 6C repeats expansion and reduction at a predetermined frequency. Since the ultrasonic vibrator 6C is provided so as to come into contact with the heat sink vibrating body 62, the vibrating body 62 is slightly vibrated without substantially vibrating the heat sink base 61 having a relatively large mass. At this time, since the fin 6B fixed to each groove formed in the vibrating body 62 has a thin flat plate shape, the fin 6B is ultrasonically vibrated by the vibration of the vibrating body 62.

  When fine vibration is applied to the plurality of fins 6B by the ultrasonic vibrator 6C, the air in the heat dissipation space is blown and stirred. Therefore, convection of air in the heat dissipation space whose temperature is rising due to heat dissipation is promoted, and hot air is positively released out of the projector, and is replaced with outside air having a relatively low temperature. As a result, the temperature rise in the heat dissipation space can be suppressed and the heat dissipation effect can be further enhanced.

  As described above, in the heat sink 6 of the projector according to the embodiment, since the ultrasonic transducer 6C is housed in the heat sink body 6 of the heat sink 6, it is difficult to be damaged. In addition, since the plurality of fins 6B have a thin flat plate shape, they easily vibrate by ultrasonic vibration, and the ultrasonic vibrator 6C vibrates the fins 6B by vibrating at a high frequency outside the range of human hearing. The problem does not occur. In particular, in the projector according to the embodiment, since the ultrasonic vibrator 6C vibrates the heat sink vibrator 62, the LED 2 of the light source hardly vibrates and does not generate light fluctuations as long as a human can experience it. .

  Specifically, the ultrasonic vibrator 6C is a piezoelectric ceramic. In the projector of the embodiment, a plurality of thin rectangular plate-shaped or disk-shaped ultrasonic transducers 6C formed by stacking sintered ceramic plates and electrode plates are dispersedly arranged in a state of being electrically insulated from the heat sink body 6A. doing. For example, as shown in FIG. 2, four rectangular plate-shaped piezoelectric ceramics are arranged. Therefore, according to the projector of the embodiment, it is possible to reduce the area occupied by the ultrasonic transducer 9 </ b> C at the joint surface between the heat sink base 61 and the heat sink vibrating body 62 and suppress a decrease in thermal conductivity.

  Since the projector according to the embodiment described above is configured to finely vibrate thin flat fins by ultrasonic vibration, the heat dissipation effect can be improved, and a relatively large LED used outdoors. Suitable for floodlights. The projector according to the present invention is not limited to the specific embodiment shown in the drawings, and as some examples have already been given, the projector according to the embodiment is modified without departing from the object of the present invention. It is possible to implement by applying. For example, it is possible to selectively apply vibration directly to the plurality of fins by providing a plurality of ultrasonic transducers at the fin attachment site outside the heat sink body.

  The LED type projector of the present invention is particularly useful for lighting required outdoors such as lighting for night lighting equipment in a playground, garden lighting, signboard lighting, and lighting at a construction site, and is implemented in various industries. Is possible. The projector of the present invention reduces power consumption, does not contain a designated harmful substance, is relatively safe, and contributes to the popularization of LED projectors.

1 Emitter body 2 Light-emitting diode element (LED)
3 Substrate 4 Support 5 Reflector 5A Condensing part 5B Irradiation part 6 Heat sink 6A Heat sink body 6B Fin (heat sink)
6C Ultrasonic vibrator 61 Heat sink base 62 Heat sink vibrator 7 Reinforcing material

Claims (1)

A substrate on which a plurality of light emitting diode elements as light sources are disposed;
A base that is configured so that a hole-shaped space is formed on the inner side and that tightly fixes the substrate to a surface on which the space is not formed, and a base that is fixed to the base so as to cover the space with a lid . parallel to each other in the main body and a small predetermined distance as possible are formed by the thin plate grooves of the plurality of straight lines on the opposite side made of parallel-formed have that vibrator respectively with respect to a plane closely fixed to the substrate A plurality of fins that are respectively fitted to the plurality of straight grooves formed in the vibrator of the main body, and the base of the main body and the vibrator are formed. A heat sink composed of a square plate-shaped or disk-shaped ultrasonic transducer provided in the space so as to be in contact with the vibrating body and vibrating the fin;
A light emitting diode type projector.

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