JP5749240B2 - Thermostatic device - Google Patents

Description

  The present invention relates to a thermostatic device used for a temperature accelerated life test of an LED (Light Emitting Diode).

  The LED is a light source characterized by a long life, but the brightness is gradually attenuated as the lighting time increases. Therefore, a standard called “IES LM-80” established by the “North American Lighting Engineering Association” is known as one of the methods for evaluating the LED lifetime. This standard tests the brightness maintenance rate (light flux maintenance rate) with respect to the lighting time of the LED, and evaluates the LED life depending on whether or not the test result is a certain value or more.

  Specifically, for the specimen LEDs driven with the same current value, continuous for 6000 hours (250 days) under three kinds of temperature conditions of 55 ° C., 85 ° C. and any temperature determined by the manufacturer (maximum 125 ° C.) It is a test method in which the brightness of the LED is measured every 1000 hours. When performing such a test, it is necessary to maintain the LED as a specimen at a constant temperature for a long period of time, but conventionally, a hot-air circulation type thermostat is frequently used.

  However, when the LED, which is a specimen, is set in a hot air circulation type thermostatic chamber, the hot air circulating in the thermostatic chamber may directly hit the LED to maintain the temperature, which may adversely affect the test results. There is sex. Moreover, since the conventional warm air circulation type thermostat has a surface inferior in uniformity of temperature distribution in the bath, when a plurality of LEDs are accommodated, the test accuracy may be lowered.

  On the other hand, various types of test devices have been conventionally proposed as a device for performing a temperature accelerated life test of an LED. Examples of devices related to the present invention include test devices described in Patent Documents 1 and 2.

JP 2011-179937 A JP 2010-245348 A

  The LED life test apparatus described in Patent Document 1 performs testing by placing one LED under test in the HAST apparatus, so the uniformity of temperature distribution is excellent, but when performing a life test on a plurality of LEDs, ineffective.

  Since the test device described in Patent Document 2 can arrange a plurality of light emitting devices in a constant temperature and humidity chamber, the efficiency when performing a life test of a plurality of LEDs is good. It is difficult to maintain a uniform temperature. In addition, the temperature in the thermo-hygrostat rises and exceeds the set temperature due to the heat ray component contained in the light beams of the plurality of LEDs that emit light continuously, which may adversely affect the test results. Such a situation becomes more conspicuous as the LED to be tested has a higher output (high luminance), and in recent years, it has become difficult to perform an accurate life test on an LED that tends to increase in luminance. ing.

  The problem to be solved by the present invention is to provide a thermostat capable of maintaining a plurality of LEDs in a stable atmosphere at a uniform temperature in an LED temperature accelerated life test.

The first thermostat according to the present invention is arranged so as to cover a thermostat plate having heating means and cooling means, a plurality of specimen mounting stages arranged on the thermostatic plate, and the specimen mounting stage. A partition member surrounding each of the specimen mounting stages, a lid member having a translucent ceiling member for closing the upper part of the specimen mounting stage surrounded by the partition member, the thermostat plate, and the specimen mounting At least one of a cover that covers the stage and the lid member, and an air supply fan that introduces gas into the cover or an exhaust fan that discharges the gas inside the cover is provided.

The second constant temperature apparatus according to the present invention is disposed so as to cover a constant temperature plate having heating means and cooling means, a plurality of specimen mounting stages arranged on the constant temperature plate, and the specimen mounting stage. A lid member surrounding each of the specimen mounting stages, a lid member having a translucent ceiling member closing the upper part of the specimen mounting stage surrounded by the partition members, the thermostat plate, the serving A cover for covering the specimen mounting stage and the lid member, and temperature control means for adjusting the temperature in the cover are provided.

  Moreover, in the thermostat, it is desirable to provide a vent hole in the ceiling member.

  Further, in the thermostatic device, as the cooling means for the thermostatic plate, a liquid passage through which a coolant can flow can be provided in the thermostatic plate.

  In this case, it is preferable that the cooling liquid is introduced into the liquid flow path located at the center of the constant temperature plate and discharged from the liquid flow path positioned at the periphery of the constant temperature plate.

  Further, it is desirable to provide a liquid temperature adjusting means for raising or lowering the temperature of the coolant supplied to the liquid passage.

  On the other hand, as a cooling means for the constant temperature plate, at least one of a heat sink or a heat pipe may be attached to the constant temperature plate, and a blower fan for cooling the heat sink or the heat pipe may be provided.

  Further, a cooling member having a Peltier element can be attached to the constant temperature plate as a cooling means for the constant temperature plate.

  The gap between the specimen mounting stage and the ceiling member is preferably 3 mm to 15 mm (desirably 8 mm to 10 mm).

  According to the present invention, it is possible to provide a thermostat capable of maintaining a plurality of LEDs in a stable atmosphere at a uniform temperature in a temperature accelerated life test of the LEDs.

It is a partially-omission perspective view which shows the thermostat which is embodiment of this invention. FIG. 2 is a partially omitted front view of the thermostatic device shown in FIG. 1. It is a top view which shows the test body heating part which comprises the thermostat shown in FIG. It is a front view of the specimen heating part shown in FIG. FIG. 4 is a perspective view of a specimen heating unit shown in FIG. 3. It is a front view which shows the specimen heating part and preheating plate which comprise the thermostat shown in FIG. It is the perspective view which looked at the test piece heating part shown in FIG. 6 from diagonally downward. It is a top view of the preheating plate in the BB line in FIG. It is sectional drawing in the AA line in FIG. It is a partially-omission front view which shows the outline | summary of the thermostat which is other embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIGS. 1 to 5, a thermostatic device 100 according to the present embodiment includes a thermostatic plate 10 having an electric heater 11 as a heating unit and a liquid passage 12 (see FIG. 7) as a cooling unit, and a thermostatic plate 10. A plurality of specimen mounting stages 30 arranged on the soaking plate 20 laminated thereon, and a lid member 50 that covers the plurality of specimen mounting stages 30 so as to be openable and closable are provided. The lid member 50 includes a partition member 51 having an opening 51a that surrounds the periphery of the plurality of specimen mounting stages 30, and a translucent ceiling member that closes the top of the specimen mounting stage 30 surrounded by the partition member 51. 52.

  The lid member 50 is locked so as to be raised and lowered via a plurality of hinges 53 disposed on the back surface of the constant temperature plate 10 and the soaking plate 20, and is used on the front surface of the lid member 50 when the lid member 50 is opened and closed. And a lock member 55 for maintaining the state when the upper surface of the soaking plate 20 is covered with the lid member 50. The ceiling member 52 is provided with a plurality of vent holes 52a having the same phase as the arrangement interval of the plurality of specimen mounting stages 30.

  A specimen heating unit 70 composed of the constant temperature plate 10, the specimen mounting stage 30, the lid member 50, and the like is disposed on the upper surface of a rectangular parallelepiped casing 80, and an openable cover 90 that covers the specimen heating part 70 is provided. The casing 80 is attached to the back side of the upper surface of the casing 80 via a plurality of hinges 91 so as to be raised and lowered. The cover 90 is a rectangular parallelepiped box-like member having an open bottom surface, and an air supply fan 92 for introducing gas into the cover 90 is attached to the bottom surface of the ceiling 90 a of the cover 90. A flat partition wall 93 parallel to the ceiling portion 90 a is disposed below the air supply fan 92, and a plurality of ventilation holes 93 a are formed in the partition wall 93. In addition, a plurality of ventilation holes (not shown) are also formed in the portion directly above the air supply fan 92 of the ceiling portion 90a. The plurality of vent holes 93 a opened in the partition wall 93 are in phase with the arrangement interval of the plurality of specimen mounting stages 30.

  As shown in FIG. 5 and FIG. 6, the liquid temperature is adjusted in the casing 80 immediately below the specimen heating unit 70 including the constant temperature plate 10, the soaking plate 20, the specimen mounting stage 30 and the lid member 50. A preheating plate 40 as a means is arranged. As shown in FIGS. 1 and 2, on the front surface of the casing 80, a flow meter 81 that displays the flow rate of the coolant supplied to the liquid passage hole 12 (see FIG. 7) of the constant temperature plate 10 and the flow rate are increased or decreased. A flow control dial 82 is arranged. A signal tower 83 having a plurality of light emitting portions 83 a, 83 b, 83 c is erected at a position near the back side of the left side surface of the casing 80. The plurality of light emitting units 83a, 83b, and 83c are set so as to emit light with different color lights according to the operation status of the thermostatic device 100, respectively.

  Next, the specimen heating unit 70 will be described with reference to FIGS. As shown in FIGS. 3 to 5, in the specimen heating unit 70, a plurality of specimen mounting stages 30 are placed on the upper surface of the soaking plate 20 stacked on the constant temperature plate 10 having a substantially square shape in plan view. A total of 25 pieces are arranged detachably along the direction W and the front-rear direction V at a regular interval of 5 pieces each. On the upper surface of the heat equalizing plate 20, grooves 21 penetrating in the left-right direction W are formed between the specimen mounting stages 30 adjacent to each other in the front-rear direction V. These grooves 21 are used as wiring spaces such as a power supply line (not shown) to the LED set on the specimen mounting stage 30 and a signal line (not shown) of a temperature sensor for measuring the temperature in the vicinity of the LED. can do.

  The partition wall member 51 constituting the lid member 50 is a flat plate-like member having a substantially circular opening 51 a opened in the same phase as the plurality of specimen mounting stages 30 arranged on the soaking plate 20. In the partition wall member 51, the plurality of partition walls 51b that divide the opening portions 51a adjacent to each other in the left-right direction W are continuous in the front-rear direction V, and the electric heater 56 is disposed in the state of being accommodated in each partition wall 51b.

  When the lid member 50 is laid down horizontally and the upper surface of the soaking plate 20 is covered, the plurality of specimen mounting stages 30 are respectively fitted into the openings 51a of the partition wall member 51, and the upper surface of the soaking plate 20 and the lower surface of the partition member 51 Are in close contact with each other. In the thermostat 100, the shape of the specimen mounting stage 30 and the opening 51a in plan view are both substantially circular, but the shape is not limited to these. The shape (for example, the shape in plan view is a square shape, an elliptical shape, or a polygonal shape) can also be used.

  Further, the partition wall member 51 located between the specimen mounting stages 30 adjacent in the front-rear direction V is provided with a notch 51c. Like the groove 21 on the upper surface of the soaking plate 20, the notch 51c is a power supply line (not shown) to the LED set on the specimen mounting stage 30 and a signal line of a temperature sensor that measures the temperature in the vicinity of the LED. It can be used as a wiring space (not shown). When the upper surface of the soaking plate 20 and the lower surface of the partition wall member 51 are in close contact with each other, the notch 51 c is in communication with the groove 21 of the soaking plate 20.

  Next, the constant temperature plate 10 and the preheating plate 40 will be described with reference to FIGS. As shown in FIGS. 6 to 8, the constant temperature plate 10 is a member formed of a substantially square metal plate. The plate surface direction and the front-rear direction V are arranged in a region between the front surface and the back surface and closer to the upper surface. A plurality of heater accommodating holes 13 are formed at equal intervals so as to be parallel to each other, and the electric heaters 11 are accommodated in the heater accommodating holes 13, respectively. In addition, a plurality of liquid passages 12 are formed at equal intervals so as to be parallel to the plate surface direction and the left-right direction W in a region between the right side surface and the left side surface of the constant temperature plate 10 and closer to the lower surface.

  The plurality of heater housing holes 13 and the plurality of liquid passages 12 are in a state of three-dimensionally intersecting with each other in the constant temperature plate 10. Further, both end portions of the liquid passage 12 are opened on the right side surface and the left side surface of the thermostatic plate 10, and the connectors 14 are attached to the respective opening portions 12a. Central portions of the plurality of liquid passages 12 communicate with the openings 12b provided on the lower surface of the constant temperature plate 10, and connectors 18 are connected to the respective openings 12b.

  As shown in FIGS. 6 and 8, the preheating plate 40 is formed by attaching planar electric heaters 44 to the upper and lower surfaces of a plate body 43 formed of a substantially square metal plate. A liquid supply pipe 85 for introducing the coolant into the preheating plate 40 is connected to the left and right openings 41 on the back surface of the plate body 43, and the temperature of the preheating plate 40 is adjusted in the preheating plate 40. A plurality of openings 42d for allowing the coolant to flow out toward the constant temperature plate 10 are provided, and the coolant pipe 45 is connected via a connector 42e attached to each opening 42d.

  As shown in FIG. 8, a plurality of openings located in the central portion of the plate main body 43 in the left-right direction W from the left and right openings 41 on the back surface of the plate main body 43 are provided inside the plate main body 43 constituting the preheating plate 40. A liquid passage 42 reaching 42d is formed. The liquid passage 42 communicates between the straight pipe portions 42a arranged in parallel in the front-rear direction V in the plate main body 43 and the adjacent straight pipe portions 42a on the front side and the back side in the plate main body 43. And a joining pipe part 42c that unifies the two straight pipe parts 42a located near the center in the left-right direction W, with a predetermined distance along the longitudinal direction of the joining pipe part 43c. A plurality of openings 42d are opened.

  The cooling liquid fed into the liquid passage 42 of the preheating plate 40 heated to a predetermined temperature by the electric heater 44 via the plurality of liquid supply pipes 85 is a straight pipe part 42a, a folded part 42b, and the like. Is heated to a predetermined temperature while passing through and flows into the joining pipe portion 42c, and flows out from the plurality of openings 42d into the coolant pipe 45 through the connectors 42e.

  The coolant that has flowed into the cooling pipes 45 rises in the respective cooling pipes 45, and is connected to the upper ends of the cooling pipes 45 through the connectors 18 and the openings 12 b on the lower surface of the constant temperature plate 10. It flows into the central part of the liquid passage 12. The coolant that has flowed into the liquid passage 12 is divided into left and right inside thereof, discharged from the openings 12a on the left and right side surfaces of the constant temperature plate 10, and discharged through a drain pipe 86 connected to the openings 12a via the connector 14. It is discarded to a predetermined drainage route via, or reused through a predetermined processing step.

  When using the thermostat 100, as shown in FIGS. 1 and 5, the cover 90 and the lid member 50 are opened, and the LEDs as the specimens are placed on the plurality of specimen mounting stages 30, respectively. After wiring of the signal line of the temperature sensor, the lid member 50 is closed, the lid member 50 is locked by the lock member 55, and the specimen heating unit 70 is covered by the cover 90. Thereafter, power supply to the electric heater 11 of the constant temperature plate 10, the electric heater 56 of the lid member 50, and the electric heater 44 of the preheating plate 40 is started, and supply of a cooling liquid (for example, water) to the liquid supply pipe 85 is started. Start and operate the cooling fan 92. Thereby, the LED on the specimen mounting stage 30 rises to a preset temperature (for example, 55 ° C., 85 ° C. or 125 ° C.) and is held at that temperature.

  In the thermostat 100, the plurality of specimen mounting stages 30 are partitioned from the atmosphere by the partition walls 51b and the ceiling member 52, respectively, and are continuously heated to a predetermined temperature by the thermostat plate 10 and the lid member 50 having a heating function. Therefore, the plurality of LEDs set on each specimen mounting stage 30 can be held in a stable atmosphere at a uniform temperature. Moreover, since ventilation is ensured through the vent hole 52a of the ceiling member 52 in the vicinity of the specimen mounting stage 30, it is possible to prevent overheating of the LEDs. Therefore, the temperature accelerated life test of the plurality of LEDs can be efficiently performed with high accuracy.

  Further, since the outside air is sent into the cover 90 from the air supply fan 92 provided in the ceiling portion 90a of the cover 90 via the vent hole 93a of the partition wall 93, the temperature rise in the cover 90 can be suppressed. It is effective for preventing overheating of the LED. Since the outside air sent into the cover 90 by the air supply fan 92 is discharged through the gap provided on the peripheral edge 90b of the lower surface of the cover 90 and the upper surface of the casing 80, the atmospheric pressure in the cover 90 is abnormal. It will not rise.

  Furthermore, as shown in FIG. 9, if the gap X between the specimen mounting stage 30 and the ceiling member 52 is 3 mm to 15 mm (preferably 8 mm to 10 mm), and the LED is disposed closest to the ceiling member 52, the LED is generated from the LED. Since most of the emitted light passes through the ceiling member 52 and diverges, the light of the LED irradiated to the partition member 51 and the like can be greatly reduced. Therefore, the temperature rise of the partition member 51 etc. resulting from irradiation of the heat ray contained in the light of LED can be prevented.

  Further, as a cooling means for the constant temperature plate 10, the constant temperature plate 10 that is continuously heated by the electric heater 12 is reliably provided by providing the constant temperature plate 10 with a plurality of liquid passage holes 12 through which the coolant can flow. And since it can cool equally, overheating can be prevented and it is effective for the improvement of temperature accuracy.

  In this case, by providing the preheating plate 40 as a liquid temperature adjusting means for raising the temperature of the coolant supplied to the liquid flow path 12, the temperature of the coolant supplied to the liquid flow path 12 of the constant temperature plate 10 is controlled to a constant temperature. Since the plate 10 can be supplied close to the set temperature of the plate 10 itself, temperature fluctuations of the constant temperature plate 10 can be suppressed, which is effective for stabilizing the heating temperature.

  Further, the coolant is introduced into the liquid passage 12 from the opening 12b located at the center in the left-right direction W of the constant temperature plate 10, and the liquid passage 12 opening located on the left and right side surfaces which are the peripheral portions of the constant temperature plate 10. Since it discharges | emits from the part 12a, it is effective in suppressing the temperature fluctuation of the constant temperature plate 10 by inflow of cooling water.

  Moreover, since the partition wall member 51 constituting the lid member 50 is provided with the electric heater 56 as a sub-heating means, the partition wall member 51 itself also has a heating function, so that the heat uniformity can be improved.

As described above, the constant temperature apparatus 100 is provided with the specimen heating unit 70 (constant temperature plate 10, specimen mounting stage 30 and the lid member 5 0 etc.) openable cover 90 for covering a specimen heating unit 70 By covering the whole with a cover, it is possible to prevent heat dissipation and thermal effects due to outside air.

  Next, based on FIG. 10, the thermostat 200 which is other embodiment of this invention is demonstrated. In the thermostat 200 shown in FIG. 10, parts having the same structure and function as the constituent parts of the thermostat 100 described above are given the same reference numerals as those in FIGS. 1 to 9 and description thereof is omitted.

  As shown in FIG. 10, the thermostatic apparatus 200 arranges a specimen heating unit 70 composed of the thermostatic plate 10, the soaking plate 20, the lid member 50 and the like on the upper surface of the casing 80 and covers the specimen heating part 70. An inner cover 90x and an outer cover 90y covering the outer periphery of the inner cover 90x are provided, and the temperature adjusting means 96 and the blower fan 97 are disposed in a ventilation path 95 formed between the inner cover 90x and the outer cover 90y. ing. Further, the right side wall 90xa and the left side wall 90xb of the inner cover 90x have air permeability.

  When performing the temperature accelerated life test of the LED using the specimen heating unit 70, when the temperature control unit 96 and the blower fan 97 are operated, the temperature control gas adjusted to a predetermined temperature by the temperature control unit 96 is changed to the blower fan 97. The gas passes through the right side wall 90xa and is sent into the inner cover 90x, passes through the inside of the inner cover 90x, passes through the left side wall 90xb, is discharged into the ventilation path 95, and is adjusted by the temperature control means 96. Then, the air is sent again into the inner cover 90x by the blower fan 97.

  In this manner, the temperature inside the inner cover 90x is maintained at a predetermined temperature by operating the blower fan 97 and the temperature adjusting means 96 and circulating the temperature adjusting gas between the inside of the inner cover 90x and the ventilation path 95. Therefore, it is possible to prevent the influence of heat due to the outside air, and it is possible to maintain a plurality of LEDs in a stable atmosphere at a uniform temperature in the temperature accelerated life test of the LEDs.

  On the other hand, the cooling means for the constant temperature plate 10 is not limited to the above-described one. However, as other cooling means, although not shown, a heat sink is attached to the lower surface, outer peripheral surface, etc. of the constant temperature plate 10 to cool the heat sink. A fan can also be provided. In this case, it is desirable to provide a cover for airflow rectification between the heat sink and the blower fan.

  Although not shown in the figure as a cooling means for the constant temperature plate 10, a heat pipe is attached to the lower surface or outer peripheral surface of the constant temperature plate 10 via a heat conducting member, and a heat sink is attached to a part of the heat pipe. A blower fan for cooling the heat sink can also be provided. Also in this case, a cover for airflow rectification can be provided between the heat sink and the blower fan.

  Furthermore, although not shown as a cooling means for the constant temperature plate 10, a cooling member having a Peltier element can be attached to the constant temperature plate 10.

  In addition, the thermostat 100,200 etc. which were demonstrated based on FIGS. 1-10 show an example of this invention, and the thermostat of this invention is not limited to the thermostat 100,200 mentioned above.

  The thermostat according to the present invention can be widely used in fields such as the electronic / electric equipment industry or the machine industry where temperature accelerated life tests of various LEDs are performed.

DESCRIPTION OF SYMBOLS 10 Constant temperature plate 11,44,56 Electric heater 12 Flow path 12a, 41,42d Opening 13 Heater accommodation hole 14,18,42e Connector 20 Soaking plate 21 Groove 30 Specimen mounting stage 40 Preheating plate 42 Liquid flow path 42a Straight pipe part 42b Folding part 42c Merge pipe part 43 Plate body 50 Lid member 51 Bulkhead member 51a Opening part 51b Bulkhead 51c Notch part 52 Ceiling member 52a, 93a Vent hole 53, 91 Hinge 54 Grip 55 Lock member 70 Specimen heating Part 80 Caging 81 Flow meter 82 Flow rate adjustment dial 83 Signal tower 83a, 83b, 83c Light emitting part 90 Cover 90a Ceiling part 90b Peripheral part 90x Inner cover 90y Outer cover 92 Air supply fan 93 Partition 96 Temperature control means 97 Blower fan 100, 200 Heng Apparatus V front and back direction W left and right direction X gap

Claims (9)

A constant temperature plate having a heating means and a cooling means, a plurality of specimen mounting stages arranged on the constant temperature plate, and a partition wall that is arranged so as to cover the specimen mounting stage and surrounds each of the specimen mounting stages A lid member having a translucent ceiling member that closes the upper part of the specimen mounting stage surrounded by the member and the partition member, a thermostat plate, a cover that covers the specimen mounting stage and the lid member, A thermostatic device comprising at least one of an air supply fan for introducing gas into the cover or an exhaust fan for discharging gas within the cover. A constant temperature plate having a heating means and a cooling means, a plurality of specimen mounting stages arranged on the constant temperature plate, and a partition wall that is arranged so as to cover the specimen mounting stage and surrounds each of the specimen mounting stages A lid member having a translucent ceiling member that closes the upper part of the specimen mounting stage surrounded by the member and the partition member, a thermostat plate, a cover that covers the specimen mounting stage and the lid member, A temperature control device comprising a temperature control means for adjusting the temperature in the cover.   The thermostat according to claim 1 or 2, wherein a ventilation hole is provided in the ceiling member.   The thermostat according to any one of claims 1 to 3, wherein a liquid passage through which a coolant can flow is provided in the thermostat plate as a cooling means for the thermostat plate.   The thermostatic device according to claim 4, wherein the cooling liquid is introduced into the liquid flow path located at a central portion of the constant temperature plate and discharged from the liquid flow path positioned at a peripheral portion of the constant temperature plate.   The thermostat according to claim 4 or 5, further comprising a liquid temperature adjusting means for raising or lowering the temperature of the coolant supplied to the liquid passage.   The thermostat according to any one of claims 1 to 3, wherein at least one of a heat sink or a heat pipe is attached to the thermostat plate as a cooling means for the thermostat plate, and a blower fan for cooling the heat sink or the heat pipe is provided. .   The constant temperature apparatus in any one of Claims 1-3 which attached the cooling member which has a Peltier element to the said constant temperature plate as a cooling means of the said constant temperature plate.   The thermostat according to any one of claims 1 to 8, wherein a gap between the specimen mounting stage and the ceiling member is 3 mm to 15 mm.

Images