JP2012048870A - Water-cooled led lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-cooled LED lighting device capable of maintaining high cooling performance irrespective of mounting angles.SOLUTION: In the water-cooled LED lighting device for cooling an LED light source unit by making cooling water circulate a circulation pump 17, a reserve tank 18, a water-cooled jacket 14, and a radiator 15 in turn in a closed circuit, two sets of first and second cooling water piping (routes) 22, 23 are led from upper and lower sides of the reserve tank 18, the cooling water piping (the second route) 23 is connected with the water-cooled jacket 14, and the cooling water piping (the first route) 22 is connected with the middle of the cooling water piping 23. Then, check valves (reverse flow preventing units) 24, 25 for preventing reverse flows of the cooling water and air from the water-cooled jacket 14 to the reserve tank 18 are respectively arranged on the respective cooling water pipings 23, 22.

Description

  The present invention relates to a water-cooled LED lighting apparatus in which an LED light source unit is forcibly water-cooled by cooling water circulating in a closed circuit.

  In recent years, lighting devices such as vehicular headlamps and outdoor lighting lamps have been changed from those using a high-intensity lamp such as a xenon lamp or sodium lamp as a light source to those using a long-life and low-power consumption LED as a light source. Replacement is progressing, and higher output is desired for LED lighting devices using LEDs as light sources.

  By the way, currently popular xenon lamps have a large output of about 200 W to 2000 W, and the power input to the LED lighting device as a substitute for this tends to increase. Recently, the power input to one LED lighting device is increasing. The thing whose electric power exceeds 200W has been developed.

  Since the amount of heat generated by the LED light source unit increases as the power of the LED lighting device increases, a cooling structure for driving the temperature lower and stably in an LED light source whose life and output change depending on the temperature. It is an important development issue.

  Therefore, for example, in Patent Document 1, the LED mounting substrate is pressed and fixed to a metal heat dissipation fixing plate by a metal heat dissipation cover, and the heat dissipation fixing plate to which the LED mounting substrate is fixed is provided with a translucent cover and a resin case. The structure which arrange | positions in the sealed space formed by (2) and forms a some heat radiating fin in the heat radiating fixed plate is proposed.

  Further, Patent Document 2 discloses an LED as a light source, a heat sink capable of air-cooling or cooling the LED, a light-emitting circuit that applies a current for causing the LED to emit light, and a water droplet that detects that the lighting device is in water. In a lighting device equipped with a sensor, when the water drop sensor detects that the lighting device is not in water, the light emitting circuit limits the current supplied to the LED to prevent overheating of the LED, and the lighting device is in water A configuration has been proposed in which a light emitting circuit supplies a high current to an LED to increase the light emission luminance of the LED.

  Furthermore, in recent years, a water-cooled LED lighting device has been proposed in which the LED light source unit is forcibly water-cooled with cooling water circulating in a closed circuit. Here, the system configuration of the water cooling unit of the water-cooled LED lighting device will be described with reference to FIG.

  FIG. 11 is a system configuration diagram of a water-cooling unit of a conventional water-cooled LED lighting apparatus. The illustrated water-cooling unit 105 is configured by providing a circulation pump 117, a reserve tank 118, a water-cooling jacket 114, and a radiator 115 in a closed circuit. In addition, when the cooling water circulates in the closed circuit by the circulation pump 117, the LED light source unit (not shown) is forcibly water-cooled and the temperature rise is suppressed.

  That is, an LED light source unit (not shown) is in close contact with the water cooling jacket 114, and the cooling water sent from the circulation pump 117 is introduced into the water cooling jacket 114 through the reserve tank 118 as shown by an arrow in FIG. The LED light source unit in close contact with the water cooling jacket 114 is then cooled. Then, the cooling water whose temperature has risen due to the cooling of the LED light source unit is introduced into the radiator 115, cooled by heat dissipation in the radiator 115, and then sucked into the circulation pump 117. The light source unit is continuously cooled.

JP 2002-299700 A JP 2003-047914 A

  By the way, the cooling water circulating through the closed circuit of the water cooling unit 105 shown in FIG. 11 is not sealed by the same amount (full tank amount) with respect to the volume of the closed circuit, and air exists above the reserve tank 117. . In addition, although a part of the closed circuit piping is constituted by a rubber hose, a part of the cooling water evaporates from the rubber hose with the passage of time, so that the ratio occupied by the air layer increases.

  Thus, as shown in FIG. 11, when the LED lighting device is used in a state where the water-cooling jacket 114 to which the LED light source unit (not shown) is closely attached is disposed downward, that is, when the light irradiation direction is downward. In this case, the air accumulated in the upper part of the reserve tank 118 does not circulate in the closed circuit together with the cooling water.

  On the other hand, as shown in FIG. 12, when the LED lighting device is turned upside down and the water cooling jacket 114 is installed upward, that is, when the light irradiation direction is upward, the LED illuminating device is accumulated at the upper part of the reserve tank 118. Since air circulates in the closed circuit together with the cooling water, there arises a problem that the cooling performance is lower than the state shown in FIG. 11 where only the cooling water circulates. Actually, even if the LED illumination device is rotated from the direct irradiation direction to an angle of 160 °, the cooling performance is not deteriorated. However, when the LED illumination device is rotated more than that (up to 180 °), the cooling performance is remarkably deteriorated. Become.

  The present invention has been made in view of the above problems, and its object is to provide a water-cooled LED lighting device that can maintain high cooling performance regardless of the installation angle.

  In order to achieve the above object, the invention described in claim 1 is a water-cooled LED lighting device that cools an LED light source unit by circulating cooling water in the order of a circulation pump, a reserve tank, a water-cooling jacket, and a radiator in a closed circuit. The first and second paths are derived from the top and bottom of the reserve tank, the second path is connected to the water cooling jacket, and the first path is connected to the middle of the second path, A backflow prevention means for preventing a backflow of cooling water and air from the water cooling jacket to the reserve tank is provided in each of the first and second paths.

  The invention according to claim 2 is characterized in that, in the invention according to claim 1, the backflow prevention means is constituted by a check valve.

  According to the present invention, for example, when the water-cooled LED lighting device is used in a direction in which the light irradiation direction is directly below, only the cooling water that has been gas-liquid separated in the reserve tank passes through the second path to the water-cooled jacket. Since the flow of the air introduced and staying in the upper part of the reserve tank from the first path to the water cooling jacket is blocked by the backflow prevention means (check valve) provided in the first path, the cooling water circulation path Air is not mixed into the water cooling unit, and high cooling performance is ensured in the water cooling unit as in the prior art.

  In addition, when the water-cooled LED lighting device is used in the direction in which the light irradiation direction is directly above from the above state, only the cooling water that has been gas-liquid separated in the reserve tank passes through the first path. Since the air introduced into the water cooling jacket and staying in the upper part of the reserve tank is prevented from flowing from the second path into the water cooling jacket by the backflow prevention means (check valve) provided in the second path, Air does not enter the water circulation path, and high cooling performance is ensured in the water cooling unit.

  Therefore, regardless of the installation angle of the water-cooled LED lighting device, air can be prevented from being mixed into the circulating cooling water and high cooling performance can always be maintained.

1 is a perspective view of a water-cooled LED lighting device according to the present invention. It is a figure of the arrow A direction of FIG. It is a figure of the arrow B direction of FIG. It is CC sectional view taken on the line of FIG. It is a front view which shows the structure of the cooling unit of the water-cooling type LED lighting apparatus which concerns on this invention. It is a figure (left side view) of the arrow D direction of FIG. It is a figure (right side view) of the arrow E direction of FIG. It is a figure (back view) of the arrow F direction of FIG. It is a system block diagram of a cooling unit in case the light irradiation direction of the water-cooled LED lighting device according to the present invention is downward. It is a system configuration | structure figure of a cooling unit in case the light irradiation direction of the water-cooling type LED illuminating device which concerns on this invention is upward. It is a system block diagram of a cooling unit when the light irradiation direction of the conventional water-cooled LED lighting device is downward. It is a system block diagram of a cooling unit when the light irradiation direction of the conventional water-cooled LED lighting device is upward.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  1 is a perspective view of a water-cooled LED lighting device according to the present invention, FIG. 2 is a view in the direction of arrow A in FIG. 1, FIG. 3 is a view in the direction of arrow B in FIG. FIG. 5 is a front view showing the configuration of the cooling unit of the water-cooled LED lighting device, FIG. 6 is a view in the direction of arrow D in FIG. 5 (left side view), and FIG. FIG. 8 is a view in the E direction (right side view), FIG. 8 is a view in the F direction of FIG. 7 (rear view), and FIG. 9 is a cooling unit system when the light irradiation direction of the water-cooled LED illumination device is downward. FIG. 10 is a system configuration diagram of the cooling unit when the light irradiation direction of the water-cooled LED illumination device is upward.

  As shown in FIG. 4, the water-cooled LED lighting device 1 according to the present invention is configured by incorporating an LED light source unit 3, a control circuit unit 4, and a water-cooling unit 5 inside a rectangular box-shaped housing 2. In addition, the upper and lower sides of the water-cooled LED lighting device 1 in the following description are in the state shown in FIG. 1, and the installation of the water-cooled LED lighting device 1 is not necessarily performed in the state shown in FIG.

  The housing 2 is made of a resin such as PC or a metal such as aluminum. As shown in FIG. 1, an air inlet 6 composed of a plurality of longitudinally long slits is formed on the peripheral surface thereof. On the surface perpendicular to the opening 6, that is, on the upper surface that is the end surface in the direction opposite to the light emission direction from the LED light source unit 3 (downward in FIG. 1) (upper in FIG. 1) An exhaust port 7 formed of a slit is formed. The lower surface of the housing 2 is open, and the LED light source unit 3 is fitted and fixed in the opening.

  As shown in FIG. 4, the LED light source unit 3 includes a plurality of (9 in the illustrated example) metal substrates 8 on which LEDs (not shown) as light sources are mounted, and a rectangular plate shape to which these metal substrates 8 are attached. The base 9 and the transparent resin lens 10 in the shape of a rectangular plate that is fitted into the lower surface opening of the housing 2 are configured.

  In the present embodiment, the nine metal substrates 8 on which the LEDs are mounted are arranged in a matrix of three rows and columns. Correspondingly, the same number of pedestals as the LEDs are provided on the aluminum die-cast base 9. 9a (refer to FIG. 4) is integrally projected in a matrix form of three columns in length and width.

  Further, as shown in FIG. 4, the control circuit unit 4 incorporates a circuit board (not shown) on which various electronic components are mounted inside a rectangular box-shaped circuit case 11 whose bottom surface is open. The opening is covered with a rectangular plate-like cover 12. Here, the circuit case 11 is formed by aluminum die casting or the like having a high thermal conductivity, and a large number of heat radiation pins 13 constituting a heat radiation portion are integrally projected on the upper surface thereof.

  As shown in FIG. 4, the water cooling unit 5 cools the water cooling jacket 14 that is a heat exchanger, and the cooling water that has received heat in the water cooling jacket 14 and increased in temperature by heat exchange with the outside air (cooling air). A radiator 15, a fan 16 for supplying cooling air to the radiator 15, a circulation pump 17 for circulating the cooling water in a closed loop circulation path, and a reserve tank 18 for storing the cooling water. The fan 16 is a radiator. 15 is arranged above and facing it.

  By the way, the water cooling jacket 14 is formed in a hollow rectangular plate shape, and a cooling water passage is formed therein. A cooling water pipe 19 extends substantially vertically upward from above the right end on the back side of the cooling jacket 14, and its end (upper end) is connected to the right end on the back side of the radiator 15. Then, the cooling water pipe 20 extends vertically downward from the left end portion on the back side of the radiator 15 and then bends substantially at a right angle and extends forward in the horizontal direction. The end portion is connected to the suction side above the circulation pump 17. It is connected.

  Further, the cooling water pipe 21 extends horizontally from the discharge side at the upper part of the circulation pump 17 toward the back side, and then is bent into a U shape when viewed from the right side and extends obliquely downward (see FIG. 7). The part is connected to the side of the reserve tank 18.

  Thus, in the present embodiment, the cooling water pipe 22 constituting the first path is formed from above the front side of the reserve tank 18, and the second side from below the back side of the reserve tank 18. The cooling water pipes 23 constituting the path are respectively led out, the cooling water pipes 23 extend vertically downward from the lower surface of the reserve tank 18, and the end portion (lower end) is connected to the left end portion on the back side of the water cooling jacket 14. Has been. A check valve 24 is provided in the middle of the cooling water pipe 23 as a backflow prevention means for preventing the backflow of cooling water and air from the water cooling jacket 14 to the reserve tank 18.

  Further, the cooling water pipe 22 extends vertically upward from the upper surface of the reserve tank 18, is then bent in an inverted U shape and directed downward, and horizontally between the circulation pump 17 and the reserve tank 18 toward the back side. After extending, it is bent at a substantially right angle and extends vertically downward, and its end (lower end) is connected between the water cooling jacket 14 of the cooling water pipe 23 and the check valve 24. A check valve 25 (see FIG. 9) is provided in the middle of the cooling water pipe 22 as a backflow prevention means for preventing the backflow of cooling water and air from the water cooling jacket 14 to the reserve tank 18. Yes.

  Thus, in the present embodiment, as shown in FIG. 4, the water cooling jacket 14 is horizontally disposed at the lower portion in the housing 2, and the control circuit unit 4 is disposed above and below the water cooling jacket 14. An LED light source unit 3 is arranged. Here, the LED light source unit 3 disposed on the lower surface side of the water-cooling jacket 14 has its base 9 in close contact with the lower surface of the water-cooling jacket 14 via a heat conductive sheet (not shown).

  The control circuit unit 4 is arranged on the upper surface side of the water cooling jacket 14 with the cover 12 being in close contact with the upper surface of the water cooling jacket 14. In this embodiment, an antifreeze liquid obtained by mixing water with propylene glycol is used as the cooling water.

  On the other hand, as shown in FIG. 4, the radiator 15 and the fan 16 are disposed in the vicinity of the upper exhaust port 7 spaced apart from the water cooling jacket 14 in the housing 2 by a predetermined distance, and the water cooling jacket 14 and the radiator 15 are arranged. A space S is formed between and an air passage S1 along the inner surface of the peripheral wall of the housing 2 is formed. The control circuit unit 4, the circulation pump 17 and the reserve tank 18 are arranged in the space S in the housing 2.

  By the way, the cooling water circulating through the closed circuit of the water cooling unit 5 is not sealed by the same amount (full tank amount) with respect to the volume of the closed circuit, and some of the cooling water pipes 19 to 23 are configured by rubber hoses. Therefore, since a part of the cooling water evaporates from the rubber hose with the passage of time, the gas and liquid are separated in the reserve tank 18, and air stays in the upper part of the reserve tank 18 as shown in FIG.

  Thus, when the water-cooled LED lighting device 1 configured as described above is activated and power is supplied to the LED light source unit 3, the control circuit unit 4, and the water-cooled unit 5, a plurality of LED light source units 3 (books) Nine LEDs in the embodiment emit light, and the light passes through the lens 10 and irradiates downward in FIG. 1 to illuminate the lower part. The lighting control of the LED light source unit 3 is controlled by a control circuit. During operation, the LED of the LED light source unit 3 and various electronic components (not shown) of the control circuit unit 4 generate heat, and the LED light source unit 3, the control circuit unit 4, and the housing 2 that houses them are left as they are. Overheating raises their temperature.

  However, in this embodiment, the water cooling unit 5 is driven at the same time, and the LED light source unit 3 and the control circuit unit 4 are forcibly cooled by the cooling water circulating in the closed circuit of the water cooling unit 5 in the direction of the arrow in FIG. The temperature rise is suppressed, and the housing 2 is forcibly air-cooled by a part of the cooling air introduced into the housing 2 from the air inlet 6 of the housing 2 by the fan 16 to suppress the temperature rise.

  That is, the cooling water discharged from the circulation pump 17 is introduced into the reserve tank 18 through the cooling water pipe 21, gas and liquid are separated in the reserve tank 18, and the air separated from the cooling water is stored in the reserve tank 18. It stays in the upper part. In this embodiment, the cooling water in the reserve tank 18 is introduced into the water cooling jacket 14 through the cooling water pipe 23, and the air staying in the upper part of the reserve tank 18 is transferred from the cooling water pipe 22 to the water cooling jacket 14. Since the inflow is blocked by a check valve 25 provided in the cooling water pipe 22, air is not mixed into the cooling water introduced into the water cooling jacket 14.

  Thus, the cooling water introduced into the water cooling jacket 14 receives the heat generated in the LED light source unit 3 and the control circuit unit 4 to cool the LED light source unit 3 and the control circuit unit 4, and receives the heat to change the temperature. The increased cooling water is introduced into the radiator 15 through the cooling water pipe 19. In this case, only the cooling water is introduced into the water cooling jacket 14 as described above, and air having low thermal conductivity is not mixed into the cooling water, so that high cooling performance is ensured in the water cooling jacket 14 and the LED light source. The unit 3 and the control circuit unit 4 are efficiently cooled.

  On the other hand, when the fan 16 is rotationally driven by a motor (not shown), outside air is sucked into the housing 2 from the side as cooling air from the air inlet 6 formed in the peripheral surface of the housing 2, and a part of this cooling air is drawn. As shown by an arrow in FIG. 4, the housing 2 is forcibly air-cooled by flowing through an air passage S1 formed along the inner surface of the peripheral wall of the housing 2 to suppress the temperature rise.

  The cooling air introduced into the housing 2 (including the cooling air that has cooled the housing 2) is a space S formed between the water cooling jacket 14 and the radiator 15, as indicated by an arrow in FIG. In the process, passes through the radiator 15, and is discharged to the outside through the exhaust port 7 that opens on the upper surface of the housing 2. In the radiator 15, the heat of the cooling water is radiated to the outside by the cooling air passing therethrough to cool the cooling water, and the cooling liquid water whose temperature has decreased passes through the cooling water pipe 21 and the circulation pump 17. Sucked into.

  The cooling water sucked into the circulation pump 17 is boosted by the circulation pump 17 and then sent out to the reserve tank 18 through the cooling water pipe 21. Thereafter, the same operation (cooling cycle) as described above is repeated to repeat the LED light source. The unit 3 and the control circuit unit 4 are forcibly water-cooled.

  On the other hand, as shown in FIGS. 1-9, the light irradiation direction is turned upside down as shown in FIG. 10 from the state where the water-cooled LED lighting device 1 is used with the light irradiation direction facing downward. When the water-cooled LED lighting device 1 is installed and used in the direction in which the water is upward, only the cooling water that has been gas-liquid separated in the reserve tank 18 as shown by the arrows in FIG. A check valve provided in the cooling water pipe 23 is introduced into the water cooling jacket 14 through the cooling water pipe 22 and flows into the water cooling jacket 14 from the cooling water pipe 23 of the air staying in the upper part of the reserve tank 18. Blocked by 24. For this reason, in this case as well, only the cooling water is introduced into the water cooling jacket 14, and air with low thermal conductivity is not mixed into the cooling water, so that high cooling performance is ensured in the water cooling jacket 14, and the LED light source unit. 3 and the control circuit unit 4 are efficiently cooled.

  Therefore, in this embodiment, regardless of the installation angle of the water-cooled LED lighting device 1, there is an effect that it is possible to always maintain high cooling performance by preventing air from entering the cooling water circulating in the closed circuit. It is done.

  In the above embodiment, the check valves 24 and 25 are used as the backflow prevention means for preventing the backflow of the cooling water and the air from the water cooling jacket 14 to the reserve tank 18, but the backflow prevention means includes two paths. Any other one can be used as long as one of the paths through which the cooling water should flow can be selected.

DESCRIPTION OF SYMBOLS 1 Water-cooled LED illuminating device 2 Housing 3 LED light source unit 4 Control circuit unit 5 Water-cooling unit 6 Intake port 7 Exhaust port 8 Metal substrate 9 Base 9a Base of base 10 Lens 11 Circuit case 12 Cover 13 Radiation pin 14 Water-cooled jacket 15 Radiator 16 Fan 17 Circulation pump 18 Reserve tank 19-23 Cooling water piping 24, 25 Check valve (back flow prevention means)
S space part S1 wind path

Claims (2)

In the water-cooled LED lighting device for cooling the LED light source unit by circulating the cooling water in the order of the circulation pump, the reserve tank, the water cooling jacket, and the radiator in the closed circuit,
The first and second paths are derived from the upper and lower sides of the reserve tank, the second path is connected to the water cooling jacket, and the first path is connected to the middle of the second path, A water-cooled LED lighting device, characterized in that backflow prevention means for preventing backflow of cooling water and air from the water cooling jacket to the reserve tank is provided in the first and second paths, respectively. The water-cooled LED lighting device according to claim 1, wherein the backflow prevention means is constituted by a check valve.

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