JPH05273085A - Method and device for inspecting heat pipe - Google Patents

Abstract

PURPOSE:To exactly and automatically inspect a heat pipe. CONSTITUTION:An inspecting device for heating an end part of a heat pipe 4 sealing working fluid for carrying heat as evaporation latent heat, detecting temperature of the other part of the heat pipe 4 and inspecting a heat pipe 4 is provided with a heater 5 for heating the end part of the heat pipe 4, a first sensor 6 for detecting the temperature of the intermediate part of the heat pipe 4, a second sensor 7 for detecting the temperature of the other end part of the heat pipe 4, a temperature difference detection means 8 for finding a temperature difference detected by the use of these sensors 6, 7 and an inspecting means 9 for inspecting the heat pipe on the basis of the found temperature difference. Exact inspection can be made since the inspection is performed on the basis of the temperature difference between two positions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting heat transfer characteristics of a manufactured heat pipe to judge its quality, and an apparatus for carrying out the method.

[0002]

2. Description of the Related Art As is well known, a heat pipe is a sealed container in which a non-condensable gas such as air is exhausted, and a fluid, such as water or chlorofluorocarbon, which evaporates and condenses in a desired temperature range, is enclosed as a working fluid. By heating one part and cooling the other part, the working fluid evaporates in the heating part and the steam flows to the cooling part and then radiates heat to transport the heat as the latent heat of evaporation. Is. This heat pipe is manufactured through steps such as cleaning the container, exhausting the non-condensable gas, injecting the working fluid, sealing the container, etc. It is shipped after checking the temperature rise characteristics. That is, if the non-condensable gas remains inside the container, the non-condensable gas is pushed into the condensing part side during operation of the heat pipe and shields the heat radiation part from the working fluid, which hinders heat transfer. It Further, if the container is not completely sealed due to poor welding or the like, a large amount of air flows into the inside of the container to prevent evaporation of the working fluid, and heat transfer is not performed. Such a defect cannot be known from the appearance of the heat pipe. Therefore, in general, the heat pipe is generally heated before being subjected to a temperature rise test and then shipped.

An example of the temperature rise test is shown in FIG.
In this test method, the lower end of the heat pipe 1, which is a sample, is immersed in warm water 2 heated to a predetermined temperature, and a thermotape 3 that discolors due to a rise in temperature is wrapped around the upper end of the heat pipe 1 to remove the warm water 2. Is a method of measuring the time from the start of heating of the heat pipe 1 to the color change of the thermotape 3.

[0004]

Although the above-mentioned conventional method is simple, it has the following problems. That is, the temperature characteristic of the thermotape is not always accurate, and since the operator visually confirms the discoloration of the thermotape, there are large individual differences in the measurement of the discoloration time. Therefore, the inspection result is not accurate, and defective products are shipped, and conversely, non-defective products are discarded and the yield is deteriorated. Further, in the above-mentioned conventional method, there is a problem that work efficiency is low and automation cannot be achieved because the operator has to determine the discoloration of the thermotape and measure the time for each.

The present invention has been made in view of the above circumstances, and provides a method capable of accurately determining whether a heat pipe is defective or not, and an automation method, and an apparatus for implementing the method. The purpose is.

[0006]

In order to achieve the above object, the method of the present invention heats one end of a heat pipe enclosing a working fluid for transporting heat as latent heat of vaporization to a predetermined temperature, and A method characterized by detecting the temperature of the intermediate portion and the temperature of the other end of the heat pipe, and determining the quality of the heat pipe based on the difference between the detected temperature of the intermediate portion and the temperature of the other end. Is.

Further, according to the present invention, the quality of the heat pipe can be determined by further adding the temperature of the middle portion or the other end portion of the heat pipe.

Further, according to the method of the present invention, if the heat pipe is erected in the vertical direction to perform heating and temperature measurement, more rapid and accurate determination can be performed.

On the other hand, in the apparatus of the present invention, as shown in FIG. 1, one end of the heat pipe 4 enclosing a working fluid for transporting heat as latent heat of vaporization is heated to a predetermined temperature, and
A quality determination device for determining the quality of the heat pipe 4 by detecting the temperature of the other part of the heat pipe 4, including a heater 5 for heating one end of the heat pipe 4, and an intermediate part of the heat pipe 4. A first sensor 6 for detecting the temperature of
A second sensor 7 for detecting the temperature of the other end of the heat pipe 4, a temperature difference detecting means 8 for obtaining the difference between the temperatures detected by these sensors 6, 7, and a pass / fail judgment based on the obtained temperature difference. It is characterized by comprising a judging means 9 for judging.

Further, in the apparatus of the present invention, the temperature detected by the first sensor 6 and the second
Other determination means for determining the quality of the heat pipe based on at least one of the temperatures detected by the sensor 7 and the temperature obtained by the temperature difference detection means 8 may be provided.

Further, the apparatus of the present invention heats one end of a heat pipe enclosing a working fluid that transports heat as latent heat of vaporization to a predetermined temperature and detects the temperature of the other part of the heat pipe to detect the heat pipe. Is a quality determination device for determining the quality of, the heat pipe is provided with a set portion to stand up the axis of the heat pipe substantially along the vertical direction, and an inspection portion having a heater for heating the lower end portion of the heat pipe. A handling mechanism is provided for transporting the heat pipe from the setting unit to the inspection unit by grasping the upper end of the heat pipe and suspending it, and further, in the inspection unit, the middle part and the upper end of the heat pipe whose lower end faces the heater. It is characterized in that a temperature detecting chuck is provided for gripping the temperature sensor and the temperature detecting sensor so that the temperature detecting sensor is brought into close contact with the outer surface of the heat pipe.

[0012]

In the method of the present invention, the temperatures at at least two points, that is, the intermediate portion and the other end portion, are measured, and the temperature difference between them is obtained. Then, since the quality of the heat pipe is determined based on the temperature difference, the quality of the temperature equalizing characteristic that the heat pipe originally should have is determined, and as a result, the quality of the heat pipe can be accurately determined. it can.

If the temperature of the intermediate portion or the other end portion is added to the temperature difference in addition to the above-mentioned temperature difference, the amount of heat transport can be known, so that a more accurate determination can be performed.

When the heat pipe is further heated, if the heat pipe is erected along the vertical direction and the lower end portion thereof is heated, the temperature equalizing tendency of the entire heat pipe is promoted, so that the determination is more accurate. Becomes

On the other hand, in the apparatus of the present invention shown in FIG. 1, one end of the heat pipe 4 is heated by the heater 5, and the temperature of the intermediate portion and the temperature of the other end, which are accompanied by it, are respectively detected by the first sensor 6. And detected by the second sensor 7. The difference between these temperatures is detected by the temperature difference detecting means 8, and if the temperature difference is equal to or more than a predetermined value, the determining means 9 determines that it is defective.

If another judging means is used instead of the above judging means 9, the first sensor 6 or the second sensor 7 can be used.
Since the determination is made by adding the temperature of the intermediate portion or the temperature of the other end detected in step 2, more accurate determination is performed.

Further, in the apparatus according to the sixth aspect, the heat pipe is erected so that the axis of the heat pipe is oriented in the vertical direction in the set portion, and the handling mechanism holds the upper end portion of the heat pipe and hangs the heat pipe. Transport. In the inspection part, the lower end of the heat pipe is heated by the heater, and at the same time, the temperature detecting chuck grips the middle part and the upper end of the heat pipe, and the temperature detecting sensor is brought into contact with these parts to detect the temperature. Therefore, the quality of the heat pipe is automatically determined.

[0018]

EXAMPLES The present invention will now be described based on examples. 2 to 4 are schematic views showing an example of the apparatus according to the present invention, and as shown in the plan view of FIG.
A single-axis robot 12 is arranged as a handling mechanism between 0 and the inspection unit 11. The setting unit 10 vertically stands up the heat pipe 14 passed from the feeder 13 in a vertical state to enable suspension and holding by the single-axis robot 12, and a pedestal 15 that rotates about a horizontal axis is provided. A clamper (not shown) for holding the heat pipe 14 is provided on the pedestal 15.

Further, the single-axis robot 12 has a guideway 1
6 is provided with a moving part 17 that moves along
A hand 18 for gripping the upper end of the heat pipe 14 is attached so as to reciprocate in a direction perpendicular to the moving direction of the moving unit 17, that is, move back and forth and move up and down.

The main structure of the inspection unit 11 is as shown in FIGS. 3A and 3B, and the heater 19 arranged at the lower end has a heating block 20 into which the lower end of the heat pipe 14 is inserted. The heating element 21 is built in the inside of the above, and two pairs of temperature detecting chucks 22 and 23 are provided above it. These temperature detecting chucks 22 and 23 are opened and closed by, for example, air pressure to grip the heat pipe 14 from the outer peripheral side, and correspond to the middle portion and the upper end portion of the heat pipe 14 in which the lower end portion is inserted into the heating block 20, respectively. It is located where you want to. Further, thermocouples 24 and 25 as temperature detecting sensors are provided on the inner surface side of the temperature detecting chucks 22 and 23, respectively. In addition,
These temperature detecting chucks 22 and 23 are configured to be water-cooled or air-cooled in order to avoid a thermal effect due to repeated heating.

Adjacent to the above-mentioned inspection section 11, there are provided a non-defective product container 26 for containing the heat pipes 14 judged to be non-defective and a defective product container 27 for inserting the heat pipes 14 judged to be defective.

FIG. 4 is a block diagram showing a control unit, in which a central processing unit (CPU) 28 controls the entire operation of the driving part in the above-mentioned device and the temperature of the heat pipe 14 is based on the detected temperature. The CPU 28 is connected to the robot controller 29 for controlling the single-axis robot 12 so as to perform data communication. The CPU 28 is also connected to the thermocouples 24, 25.
Output signal and the position signal 30 of the moving unit 17, and the CPU 28 outputs a command signal to the electromagnetic valve 31 that opens and closes the temperature detecting chucks 22 and 23 to detect the temperature detecting chucks 22 and 23. It is designed to open and close 23. On the other hand, the printer 33 is connected to the CPU 28 via the printer interface 32, and outputs the determination result of the heat pipe 14.

A method of determining the quality of the heat pipe 14 by the above-mentioned device will be described below. The heat pipe 14 as the sample is in a horizontal state from the feeder 13
Then, the pedestal 15 is fixed to the pedestal 15 by a clamper, and the pedestal 15 is rotated in this state so that the heat pipe 14 is erected vertically. At this time, the single-axis robot 1
The second moving unit 17 is stopped on the side of the setting unit 10, and when the heat pipe 14 is erected vertically, its hand 18 moves forward and holds the upper end of the heat pipe 14. When the clamper releases the fixation of the heat pipe 14, the moving unit 17 moves to the right in FIG. 2, that is, toward the inspection unit 11.

In the inspection unit 11, the hand 18 descends on the heater 19 and is suspended and held in the heat pipe 14.
The lower end of the heat pipe 14 is inserted into the heater 19 and the grip of the heat pipe 14 by the hand 18 is released. Instead, the temperature measuring chucks 22 and 23 are closed to grip the heat pipe 14, and the thermocouples 24 and 25 attached to the inner surface side thereof are brought into close contact with the outer surface of the heat pipe 14. Therefore, since the lower end of the heat pipe 14 is heated by the heater 19, the working fluid evaporates inside the heat pipe 14 depending on the state of good or bad, and heat is transported. Then, the temperatures of the intermediate portion and the upper end portion rise according to the degree of the heat transport, and the respective temperatures are detected by the thermocouples 24 and 25 attached to the temperature detecting chucks 22 and 23.

FIG. 5 is a flow chart showing a routine for judging the quality of the heat pipe 14 based on the detected temperature of each part. In Step 1, the timer T is started at the same time as the heating of the heat pipe 14 and the temperature measurement are started. In step 2, it is judged whether or not the count value has reached a predetermined value α, and if the judgment result is “no”, the control process returns, and if “yes”, the process proceeds to step 3. Next, the temperature T1 of the middle part and the temperature T2 of the upper end of the heat pipe 14 are read. Then, in step 4, it is judged whether or not the temperature T1 of the intermediate portion is equal to or higher than a predetermined reference temperature A. If the determination result is "no", the heat transport amount is insufficient, so it is determined to be defective, and a defective product signal is output (step 5). If the result of the determination in step 4 is "yes", it means that the temperature of the intermediate portion has risen to the required temperature. In this case, therefore, proceed to step 6 to determine the temperature T1 of the intermediate portion and the temperature of the upper end portion. It is determined whether or not the absolute value of the difference from the temperature T2 is less than or equal to a predetermined value B. If the judgment result is "No", the temperature-equalizing characteristic of the heat pipe 14 is bad, so the process proceeds to Step 5 to output a defective product signal, and if the judgment result in Step 6 is "Yes". ,
Proceeding to step 7, a non-defective signal is output. Then return.

FIG. 6 is a diagram showing the experimental results of examining the temperature characteristics of the non-defective product and the defective product. In the case of the non-defective product, the temperatures T1 and T2 at the middle portion and the upper end portion are both high and The difference is getting smaller. On the other hand, if the heat pipe 14 is not completely sealed due to defective welding or the like, the amount of heat transport is reduced, so that the temperature T1 of the middle portion and the upper portion is reduced.
, T2 are both low. Further, in the case of the heat pipe in which the non-condensable gas remains, the temperature T2 at the upper end which is the condensing part does not become high, and the temperature difference between the middle part and the upper end becomes large. Therefore, according to the determination routine shown in FIG.
By determining the temperature difference in step 6, it is possible to reliably determine the defect due to the remaining non-condensable gas.

After the pass / fail judgment is made as described above,
The grip of the heat pipe 14 by the temperature sensing chucks 22 and 23 is released, and the upper end of the heat pipe 14 is gripped by the hand 18 of the uniaxial robot 12, and the heat pipe 14 judged as non-defective is placed in the non-defective product box 26 and again. The heat pipe 14 determined to be a good product is conveyed to the defective product container 27 and inserted.

In the above embodiment, the heat pipe 1
However, the present invention is not limited to the above embodiment, and heating and temperature measurement may be performed at an angle close to horizontal. Further, the device of the present invention is not limited to the configuration shown in the above embodiment, the above-mentioned as a handling mechanism for transporting the heat pipe from the setting part to the inspection part, and further from the inspection part to another part. Mechanisms other than the single-axis robot can be adopted.

[0029]

As is apparent from the above description, according to the present invention, the temperatures of the middle part and the other end of the heat pipe whose one end is heated are detected, and the heat pipe based on the difference between the temperatures is detected. Since it was decided to judge pass / fail, it is possible to detect defects due to the fact that the non-condensable gas remains inside, in addition to the defects due to the poor heat transport properties as a whole, and therefore cannot be detected conventionally. It is possible to accurately find out whether the heat pipe is defective or not by identifying the defectiveness. Further, since the quality determination is performed based on the detected temperature difference, it can be mechanically determined, and the determination result is accurate in this respect as well, and in addition, the heat pipe can be automated.

[Brief description of drawings]

FIG. 1 is a block diagram showing in principle the apparatus of the present invention.

FIG. 2 is a plan view schematically showing an example of the device of the present invention.

FIG. 3 is a schematic diagram showing the main configuration of the inspection unit.

FIG. 4 is a block diagram showing the control device.

FIG. 5 is a flowchart showing an example of a determination routine.

FIG. 6 is a diagram showing the results of inspecting the temperature characteristics of non-defective and defective heat pipes.

FIG. 7 is a schematic diagram for explaining a conventional determination method.

[Explanation of symbols]

4 ... Heat pipe, 5 ... Heater, 6 ... First sensor, 7 ... Second sensor, 8 ... Temperature difference detecting means, 9
... determination means.

Claims (6)

[Claims] 1. A heat pipe enclosing a working fluid that transports heat as evaporation latent heat is heated to a predetermined temperature, and the temperature of the middle part and the temperature of the other end of the heat pipe are detected. A heat pipe quality determination method, comprising determining the quality of the heat pipe based on a difference between the detected temperature of the intermediate portion and the temperature of the other end portion. 2. A heat pipe enclosing a working fluid for transporting heat as evaporation latent heat is heated to a predetermined temperature, and the temperature of the middle part and the temperature of the other end of the heat pipe are detected, A heat pipe quality determination method for determining the quality of a heat pipe based on the difference between the detected temperature of the intermediate portion and the temperature of the other end and at least one of the temperature of the intermediate portion and the temperature of the other end. 3. The heat pipe is held substantially vertically, and the lower end of the heat pipe is heated to a predetermined temperature.
The method for determining the quality of a heat pipe according to claim 1 or 2, wherein the temperatures of the intermediate portion and the upper end portion in the vertical direction are detected. 4. The quality of the heat pipe is determined by heating one end of the heat pipe enclosing a working fluid that transports heat as evaporation latent heat to a predetermined temperature and detecting the temperature of the other part of the heat pipe. In the quality determination device, a heater that heats one end of the heat pipe, a first sensor that detects the temperature of the middle part of the heat pipe, and a second sensor that detects the temperature of the other end of the heat pipe, A heat pipe quality determination device comprising: a temperature difference detection unit that determines a temperature difference detected by these sensors; and a determination unit that determines quality based on the determined temperature difference. 5. In place of the determination means, at least one of the temperature detected by the first sensor and the temperature detected by the second sensor and the temperature obtained by the temperature difference detection means are used. The heat pipe quality determination apparatus according to claim 4, further comprising another determination unit that determines quality of the heat pipe based on the heat pipe. 6. The quality of the heat pipe is determined by heating one end of the heat pipe enclosing a working fluid that transports heat as evaporation latent heat to a predetermined temperature and detecting the temperature of the other part of the heat pipe. In the pass / fail judgment device, a set part is provided to erect the heat pipe so that its axis is substantially vertical, and an inspection part having a heater for heating the lower end of the heat pipe is provided. A handling mechanism is provided for gripping the upper end of the pipe and suspending and transporting the pipe. Further, the inspection unit grips the middle part and the upper end of the heat pipe whose lower end faces the heater, and measures the temperature. A heat pipe good / bad determination device, which is provided with a temperature detecting chuck for closely adhering the sensor to the outer surface of the heat pipe.