JP2006308368A - Test chamber for electronic device and testing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a test chamber for an electronic device, in which a uniform temperature can be maintained. <P>SOLUTION: A large number of magnetic disk devices 101 are housed in the test chamber 10 An operation test on the magnetic disk devices is performed in the temperature environment in the test chamber. Air streams formed by fans 19a and 19b are passed through a central duct 29 and heated by temperature adjusting units 21a and 21b. A duct opening is formed to the central duct and air nozzles 103 and 105 are provided corresponding to the magnetic disk devices in the duct opening. Air with a predetermined temperature is supplied to the magnetic disk devices from the air nozzles. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a test chamber that provides a temperature environment required when testing an electronic device such as a magnetic disk device, and more particularly to each electronic device when storing a large amount of electronic devices at a high density and performing an operation test. The present invention relates to a test chamber that provides a uniform temperature environment.

  In a magnetic disk device as an example of an electronic apparatus, quality is guaranteed by performing an operation test for a predetermined time in a high temperature environment such as 50 ° C. to 60 ° C. or a low temperature environment such as 0 ° C. or less before shipment. In a test process in a factory that mass-produces magnetic disk devices, it is necessary to perform operation tests on a large number of magnetic disk devices at the same time. For example, in a 1-inch type magnetic disk apparatus, several hundred units are put in one test chamber at a time and tests are performed simultaneously. The test chamber needs to keep the temperature around each magnetic disk device within a predetermined test temperature range during an operation test.

  In order to manage the test temperature for each of the hundreds of magnetic disk devices housed in the test chamber, a dedicated fan is provided for each magnetic disk device, and the amount and temperature of air supplied are individually If controlled, a predetermined test temperature can be provided to each magnetic disk device. However, according to this method, as the number of magnetic disk devices increases, the investment for the test chamber becomes enormous, or the test chamber becomes larger and occupies a great amount of floor space. Although it is effective to reduce the external dimensions of the test chamber as much as possible in terms of cost reduction and floor space reduction, the storage density of the magnetic disk device in the chamber becomes high, and the hot chamber with a higher temperature than the surroundings becomes hot. A spot or a cold spot having a temperature lower than that of the surroundings is likely to be generated, and it becomes difficult to provide an appropriate test temperature for all the magnetic disk devices.

Patent Document 1 describes a test of a disk drive in which the amount of air blown to each shelf is made uniform using a turning vane having different lengths provided in a duct and openings having different sizes provided in the duct. Disclose the chamber. In Patent Document 2, an outlet is provided in the hood and the atmosphere blown out by the cooling device is caused to flow out in different directions in the atmosphere adjustment chamber, or a shutter plate is provided to adjust the direction of airflow, flow rate, flow velocity, and the like. Thus, a thermal chamber in which the room temperature is made uniform is disclosed.
US Pat. No. 5,851,143 JP 7-260210 A

  In a test chamber that conducts an operation test by storing a large amount of electronic devices such as magnetic disk drives at high density, the electronic device itself also generates heat and changes the temperature in the chamber locally, so air is not constantly moved. And the temperature around each electronic device cannot be maintained within a predetermined range. Most test chambers have one or two fans, and the temperature adjustment unit consisting of a heater and cooler adjusts the temperature of the air flow generated by the fans, and then a central duct installed in the chamber. The configuration that is sent to is adopted. Then, air is sent from the central duct to each electronic device to generate an air flow in the vicinity of the electronic device to control the ambient temperature of each electronic device. Hereinafter, such a temperature control method for the test chamber is referred to as a central method in contrast to a method in which individual fans are provided to individually control the temperature.

  In the central type test chamber, a technique for making the amount of air supplied to each electronic device uniform by providing a rectifying plate in the duct or changing the size of the blowout opening from the duct is described in the above patent documents. It is generally adopted as well. However, in recent years, the number of magnetic disk devices has been reduced and the number of units stored in one test chamber has increased, and the test temperature conditions have become more severe. It has become difficult to provide a uniform temperature environment for magnetic disk devices. Throughout this specification, uniform temperature or uniform air volume does not mean the same temperature or the same air volume, but a predetermined range of temperatures required for testing or an air volume within a range that can satisfy the temperature conditions. I mean.

  Since magnetic disk units generate heat with various amounts of heat during operation tests, the ambient temperature of each magnetic disk unit varies depending on the temperature of the air blown from the central duct and the heat generation state of each magnetic disk unit. To do. In the central type test chamber, basically only the temperature of the air in the central duct and the air volume generated by the fan can be controlled, so that the temperature around each magnetic disk unit is not affected by the heat generated by the magnetic disk unit itself. It is necessary to. For this purpose, it is necessary to increase the amount of air blown from the central duct to each magnetic disk device and to control the ambient temperature of the magnetic disk device by the air flow of the central duct.

  Increasing the size of the fan and increasing the amount of air blown from each outlet of the central duct is one method, but it can increase the consumption of electrical energy and increase the cost of the test chamber. End up. Also, in the conventional central type test chamber, when the magnetic disk unit is stored at a high storage density, it is possible to eliminate hot spots and cold spots simply by increasing the capacity of the fan. Therefore, it was difficult to provide a uniform temperature environment. One direction for solving such problems is how to send a uniform amount of air from the central duct to each magnetic disk drive when the fan airflow is set to a certain value. Challenges appear.

  In the central type test chamber, the amount of air blown out from each air outlet is not uniform even if the opening area is increased as the position of each air outlet becomes farther from the fan. This is thought to be because the air flow inside the central duct is agitated by the fan and becomes turbulent, and the pressure loss does not change regularly according to the distance from the fan. In addition, changing the opening area or adjusting the angle of the rectifying plate to adjust the air volume of a specific outlet will change the air volume of other outlets. There is a limit to supplying a uniform air volume to the magnetic disk drive.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a test chamber capable of providing a uniform temperature environment by storing electronic equipment such as a magnetic disk device with a high storage density. It is a further object of the present invention to provide a method for determining the length of an air nozzle provided in such a test chamber.

  The amount of heat generated by each electronic device during the operation test affects the test temperature for the electronic device. In a test chamber having a structure comprising a central duct, a fan for generating an air flow between the central duct and the housing, and a temperature adjusting unit for adjusting the temperature of the air flow generated by the fan, such an electron is used. In order to keep the test temperature for each of the devices within a predetermined range, it is necessary to supply each electronic device with air whose temperature is controlled so as to eliminate the influence of heat generation of the electronic device. In order to guarantee the test temperature for all electronic equipment when the amount of air generated by the fan is determined, it is necessary to make the amount of air supplied from the central duct uniform.

  According to a first aspect of the present invention, there is provided a test chamber for accommodating a plurality of electronic devices and performing an operation test. The test chamber accommodates the electronic devices, a plurality of duct openings are formed, and an air flow passes therethrough. A central duct, a fan that generates an air flow between the central duct and the housing, a temperature adjustment unit that adjusts the temperature of the air flow generated by the fan, and power supply to each electronic device There is provided a test chamber having a plurality of connectors that can be configured and a plurality of air nozzles that are attached to the positions of the duct openings corresponding to the electronic devices and supply air to the electronic devices.

  If air is supplied by the air nozzle attached to the central duct corresponding to each electronic device, turbulent flow is generated inside the central duct and there is a difference in the amount of air blown out from each duct opening. In addition, the amount of air supplied to the electronic device by the air nozzle can be adjusted. A magnetic disk device is suitable as an example of electronic equipment. The magnetic disk drive has a flat outer shape and can be arranged in high density with a large number of lines in the chamber, which can easily eliminate hot spots and cold spots. It is convenient as a utilization form of the test chamber according to the present invention.

  If the air blown from the air nozzle outlet is directed to the base cover or the surface of the base parallel to the magnetic disk, the magnetic disk drive will be strongly affected by the temperature of the air blown by the magnetic disk drive. Therefore, it is desirable to maintain the temperature of the magnetic disk device during the test. The test chamber is provided with a test control device that communicates with the magnetic disk device. The magnetic disk device receives programs and commands from the test control device and performs test operations in various heat generation states.

  When the air nozzle is detachably attached to the central duct, the air nozzle is replaced according to the position of each duct opening so that the air flow supplied to each electronic device is uniform and the ambient temperature is within a predetermined range. Convenient. In order to adjust the air volume according to the position of the duct opening, two types of air nozzles, a long nozzle and a short nozzle, can be used. The long nozzle is configured so that the air blown from the duct opening is guided to the electronic device most efficiently. Further, when the air nozzle is configured to be extendable and contractible, the length of the flow path of the air nozzle can be adjusted steplessly, so that the amount of air can be made even more uniform.

The telescopic air nozzle can be easily configured with a fixed nozzle fixed to the central duct and a movable nozzle that slides relative to the fixed nozzle. The position of the movable nozzle, that is, the length of the flow path of the air nozzle is determined with the goal of making the amount of air supplied to each electronic device uniform. Since the test chamber according to the present invention can supply a uniform amount of air to each electronic device, it can be configured for either a high temperature environment or a low temperature environment. The test chamber according to the present invention can be used for an electronic device that hardly generates heat during an operation test or an electronic device with a constant calorific value, but is particularly suitable for an electronic device with a large fluctuation in the calorific value. For example, it is suitable for an operation test of an electronic device in which the minimum heat generation amount with respect to the maximum heat generation amount randomly varies in the range of 70% to 0% during the operation test. Even in this case, the test chamber can be configured to control the temperature in the vicinity of each electronic device by the air flow from the central duct.

  According to a second aspect of the present invention, there is provided a storage portion for storing electronic equipment, a central duct in which a plurality of duct openings are formed and an air flow passes, and an air flow between the central duct and the storage portion. A fan for generating, a temperature adjusting unit for adjusting a temperature of an air flow generated by the fan, a plurality of connectors capable of supplying power to the electronic devices, and the ducts corresponding to the electronic devices. In a test chamber comprising a plurality of air nozzles attached at positions of openings and supplying air to the respective electronic devices, a method for determining a length of the plurality of air nozzles, comprising: Setting all of the plurality of air nozzles to a certain length so that the air outlet is farthest from each electronic device, and connecting the electronic device to each of the connectors And a step of operating all the electronic devices at a maximum calorific value, a step of measuring temperatures of a plurality of guarantee points respectively set in the vicinity of the electronic devices, and a step of measuring the air in accordance with a result of the step of measuring. Providing a method for determining the length of an air nozzle comprising changing the length of the nozzle.

  First, the length of all the air nozzles is set to be constant so that the amount of air supplied from each air nozzle to each electronic device is minimized, and all the electronic devices are operated so as to have the maximum heat generation amount. Under this condition, the ratio of the electronic device affecting the temperature of the guarantee point is the largest, and the temperature increases as the guarantee point has a smaller amount of air blown from the air nozzle. Therefore, the temperature between each guarantee point can be made uniform by changing the length of the air nozzle corresponding to such a location so that the amount of air supplied to the electronic device is increased. The length of the air nozzle may be changed by preparing a plurality of air nozzles of different lengths and replacing them, or by adjusting the expansion / contraction amount of the extendable air nozzle. You may do it.

  According to the present invention, it has been possible to provide a test chamber capable of providing a uniform temperature environment by storing electronic devices such as a magnetic disk device with a high storage density. Furthermore, the present invention has provided a method for determining the length of the air nozzle provided in such a test chamber.

[Test chamber structure]
The configuration of the test chamber 10 according to the embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an outline view of a test chamber 10 that provides a high temperature environment at a higher temperature than ambient. The test chamber 10 has an outline dimension of approximately XX.times.XX. FIG. 1 shows a casing 11 and a front door 13 attached to the casing 11. Air intakes 15 and 17 each having three blocks are formed on the front surface of the housing 11. The test chamber 10 can accommodate 204 1-inch type magnetic disk devices. By adopting the test chamber configuration according to the present invention, it is possible to provide a temperature environment for storing and testing a larger number of magnetic disk devices at one time.

  FIG. 2 is a front view of the test chamber 10 in which the front door 13 is removed and the magnetic disk device 101 housed inside and the air nozzle for supplying air to the magnetic disk device 101 are shown in a simplified manner. In FIG. 2, only two nozzles, a long nozzle 103 having a long flow path from the air inlet to the outlet, and a short nozzle 105 having a short flow path are shown with reference numerals. However, pairs of the magnetic disk device 101 and the air nozzles are arranged in a matrix of 6 rows × 34 rows.

  The magnetic disk devices 101 are all the same type. By explaining the configuration of the long nozzle 103 and the short nozzle and the positional relationship between them and the magnetic disk device 101 with reference to FIG. 3 and FIG. be able to. The long nozzle 103 and the short nozzle 105 are mixedly attached to the central duct 29, and the selection method will be described later as one embodiment of the present invention.

  FIG. 3 is a side view schematically showing the inside of the test chamber 10. The test chamber 10 has a central duct 29 provided therein. The central duct 29 is composed of two horizontal portions that are coupled to the air intakes 15 and 17 of the housing 11 and extend horizontally from the front surface to the rear surface direction, and a vertical portion that extends vertically connecting the two horizontal portions. Yes. In the present embodiment, the horizontal portion and the vertical portion of the central duct are integrally formed, and fans 19a and 19b and temperature adjustment units 21a and 21b are provided inside the horizontal portion.

  The fans 19a and 19b have the same configuration, and generate air flows toward the vertical portion of the central duct 29, respectively. The temperature adjustment units 21a and 21b have the same configuration, and each of them has an electric heater inside and can heat an air flow passing through them. The amount of heat generated by the heater can be controlled by a signal from the temperature control unit 26. The airflow flowing through the central duct 29 is agitated by the fans 19a and 19b and has a substantially uniform temperature. The central duct 29 can be divided into three parts so that the horizontal part and / or the vertical part correspond to every two rows of the magnetic disk device 101 and the air nozzles arranged as shown in FIG. However, if the horizontal portion is divided into three, the number of fans and temperature adjustment units increases.

  Air dampers 23 a, 23 b, 25 a, 25 b are provided in the horizontal portion of the central duct 29. The air dampers 23a and 23b are both electrically operated, and adjust the amount of air flowing into the central duct 29 from the outside when the fans 19a and 19b are operated. The reason why air is taken in from the outside is that when the internal temperature becomes too high, air at a low temperature is taken in from outside and the temperature is lowered in a short time. The air dampers 25a and 25b are also electrically operated, and adjust the amount of air circulating through the central duct 29 and the storage unit 30 when the fans 19a and 19b are operated.

  The storage unit 30 is a room for providing a temperature environment to the magnetic disk device 101, and has a structure in which 204 magnetic disk devices 101 can be mounted so that the magnetic disks are horizontal. Temperature sensors 31 a and 31 b are attached in the vicinity of the magnetic disk device 10, and are connected to a temperature control unit 26 provided on the back surface of the central duct 29. The temperature sensors 31a and 31b are sensors that can electrically measure the temperature, and can be composed of a thermocouple, a thermistor, or a resistance temperature detector. The temperature signal of the temperature sensor 31a is used by the temperature control unit 26 to control the amount of heat of the heater of the temperature adjustment unit 21a, and the temperature signal of the temperature sensor 31b is used by the temperature control unit 26 to control the amount of heat of the heater of the temperature adjustment unit 21b. Used to do.

  A plurality of temperature sensors 31a and 31b may be provided in the vicinity of the magnetic disk device 101 for the temperature adjustment unit 21a and for the temperature adjustment unit 21b, respectively, and the average value of each may be calculated. In this case, the temperature sensor used for controlling the temperature adjustment unit 21a is arranged in the vicinity of the magnetic disk device 101 arranged in the upper half, and the temperature sensor used for controlling the temperature adjustment unit 21b is arranged in the lower half. It may be arranged in the vicinity of the magnetic disk device 101. In the test chamber 10, a test control device 27 is provided behind the central duct 29. The test control device 27 can communicate with 204 magnetic disk devices for an operation test, transfers a test program to each magnetic disk device, or sends a command to each magnetic disk device to perform a response operation. Check or monitor the progress of the operation test.

  FIG. 4 is an enlarged side view of the mounting portion of the magnetic disk device 101, the long nozzle 103, and the short nozzle 105. FIG. On the side wall of the vertical portion of the central duct 29, a duct opening 33 is formed at a location corresponding to the mounting position of each air nozzle on the storage portion 30 side. Therefore, there are 204 duct openings 33 as a whole. In this embodiment, the duct openings 33 are all the same size. An air nozzle mounting location is set around each duct opening 33, and the air nozzle can be detachably mounted with a screw so as to protrude toward the storage unit 30 side. The size of the duct opening 33 can be different depending on the position of the central duct.

  The areas of the air inlets attached to the duct opening 33 of the long nozzle 103 and the short nozzle 105 are substantially the same, and the duct opening 33 is made large so that a larger area of the air nozzle can be attached. Is formed. The long nozzle 103 includes a base plate 115 and a blowing port 119, and the short nozzle 105 includes a base plate 117 and a blowing port 121. On the side wall of the central duct 29, the substrate 107 is attached so as to protrude toward the space of the storage portion 33 corresponding to the long nozzle 103 and the short nozzle 105. A through-hole 109 is formed in the substrate 107, and an HDD holder 111 is attached to the lower surface. The HDD holder 111 may be attached to the upper surface of the substrate 107. An interface connector 113 is provided inside the HDD holder 111, and each interface connector 113 is connected to the test control device 27. When the magnetic disk device 101 is inserted into the HDD holder 111 and the connector of the magnetic disk device 101 and the interface connector 113 are connected, the signal line and the power line of the magnetic disk device 101 are connected to the test control device 27.

  Both the air outlet 119 of the long nozzle 103 and the air outlet 121 of the short nozzle 105 are positioned so as to send air to the base cover or base surface parallel to the magnetic disk of the magnetic disk device 101. The air outlet 119 of the long nozzle 103 extends to the center of the magnetic disk device 101, and the air outlet 121 of the short nozzle 105 is located closer to the central duct 29 than that. Therefore, the portion of the air flow supplied from the outlet 121 of the short nozzle 105 does not reach the magnetic disk device 101, and the long nozzle 103 supplies the magnetic disk device 101 to the magnetic disk device 101 compared to the short nozzle 105. Air volume is increasing.

[Explanation of test chamber operation]
The operation of the test chamber 10 configured as described above will be described. First, the magnetic disk device 101 to be tested is inserted into each HDD holder 111 and connected to the interface connector 113. Next, the set temperature for the temperature sensors 31 a and 31 b of the storage unit 30 is set to 60 ° C., for example, the test chamber 10 is switched on, and the temperature control unit 26 is operated. The temperature control unit 26 performs control so that the fans 19a and 19b have the maximum output, and controls the amount of heat generated by the heaters of the temperature adjustment units 21a and 21b to be maximum. Further, the temperature control unit 26 fully closes the air dampers 23a and 23b and fully opens the air dampers 25a and 25b.

  In this state, the air sent from the fans 19a and 19b passes through the vertical part of the central duct 29, circulates along the route passing through the air dampers 25a and 25b after being blown out from each air nozzle to the storage part 30. The temperature sensors 31a and 31b detect the set temperature in the minimum time. Thereafter, the temperature control unit 26 adjusts the opening degree of the air dampers 23a, 23b, 25a, 25b, or controls the heaters of the temperature adjustment units 21a, 21b, so that the detected temperatures of the temperature sensors 31a, 31b are 60. Keep at ℃.

  At this time, the air blown from the long nozzle 103 is likely to reach the magnetic disk device 101 through the through-hole 109 because the blower port 119 is directed substantially to the center of the magnetic disk device 101 as shown in FIG. . On the other hand, as shown in FIG. 4, the air blown out from the short nozzle 105 does not reach the center of the magnetic disk device 101, and therefore the amount of air that reaches the magnetic disk device 101 through the through-hole 109 is small. Less.

  However, the internal pressure of the central duct 29 at the position of the duct opening 33 corresponding to the short nozzle 105 is higher than the internal pressure of the central duct 29 at the position of the duct opening 33 corresponding to the long nozzle 103. In this case, the amounts of air supplied from both air nozzles to the magnetic disk device 101 are close to each other. Accordingly, by properly using the long nozzle and the short nozzle according to the position of the duct opening 33, the amount of air supplied to each magnetic disk device 101 can be made uniform.

[How to determine the length of the air nozzle]
Next, a method for appropriately selecting the long nozzle 103 and the short nozzle 105 for each position of the duct opening 33 will be described. The storage portion 30 of the test chamber 10 rises in temperature due to the heat of the heaters of the temperature adjustment units 21 a and 21 b and the heat generation from the magnetic disk device 101. The magnetic disk device 101 generates heat in the range of 300 mW to 1 W during the operation test, but the generation timing of each heat generation amount is random. The greater the amount of heat generated by the magnetic disk device 101, the stronger the influence on the ambient temperature of each magnetic disk device 101.

  The position in the storage unit 30 where the test chamber 10 guarantees the test temperature for each magnetic disk device 101 is called a guarantee point. In this embodiment, the guarantee point is set at a position 5 mm away from the base cover (position on the air duct side) on the vertical line at the center of the base cover of each magnetic disk device. There are 204 guarantee points corresponding to the number of magnetic disk devices 101 to be stored. In order to keep the temperature at each guarantee point within a predetermined range, it is necessary to make the amount of air supplied to each magnetic disk device uniform as a first condition. Further, as a second condition, air in a predetermined temperature range supplied from the air nozzle under the condition that the first condition is satisfied does not undergo a large temperature change due to a change in the amount of heat generated by the magnetic disk device 101. It is necessary.

  In order to satisfy the first condition, either the long nozzle 103 or the short nozzle 105 is selected according to the position of the duct opening 33. In order to satisfy the second condition, the air volume of the fans 19a and 19b is increased sufficiently. Ideally, the length of the air nozzle should be adjustable steplessly, but depending on the range of test temperatures allowed for each guarantee point, it is practical even if it can be adjusted stepwise. There is sex. In the present embodiment, the air volume is made uniform by using two types of air nozzles, the long nozzle 103 and the short nozzle 105.

  Now, it is assumed that the test chamber 10 satisfies the second condition. However, the air flow inside the central duct 29 is turbulent, and even if the duct openings 33 are all the same size, they are placed at any same stage that is equidistant from the fan 19a or the fan 19b. The amount of air blown out from the arranged duct openings 33 will be different. Further, the amount of air blown out from each duct opening 33 arranged in any same row is not necessarily regular with respect to the position from the fan 19a or the fan 19b. Therefore, in the central type chamber, there is a limit in adjusting the amount of air blown out only by adjusting the size of the duct opening 33.

  In block 201, short nozzles 105 are attached to all duct openings 33 of the central duct 29. Therefore, the amount of air supplied to each magnetic disk device 101 is minimized. In block 203, the magnetic disk device 101 is connected to each interface connector 113. At block 205, a thermocouple is installed at the warranty point. Instead of the thermocouple, other electrical temperature sensors such as a resistance temperature detector or a thermistor can be installed. Each thermocouple is connected to a temperature recorder prepared outside the test chamber 10.

  In block 207, the test control device 27 sends a command to all the magnetic disk devices 101 so that the heat generation amount is maximized. Such an operation state can be realized, for example, under conditions such that the actuator of the magnetic disk device 101 is frequently operated to perform a data read / write test. Such an operating condition of each magnetic disk device 101 can be realized by each magnetic disk device 101 executing a program incorporated in advance or transferred from the test control device 27. In this state, the influence of the heat generation of the magnetic disk device 101 on the temperature of the guarantee point is the largest.

  In block 209, the test chamber 10 is operated with a set temperature value used for the actual test, for example, 60 ° C. The temperature control unit 26 of the test chamber 10 includes the fans 19a and 19b, the temperature adjustment units 21a and 21b, and the air dampers 23a, 23b, 25a, and 25b so that the temperature detected by the temperature sensors 31a and 31b is 60 ° C. Control. In block 211, the temperature detected by each thermocouple after the temperature in the storage unit 30 rises and the internal temperature becomes stable is recorded and analyzed by a temperature recorder. Desirably, a temperature distribution diagram corresponding to the position of each thermocouple is created. The temperature of the air flowing through the central duct 29 is uniform, and the temperature of the air supplied to each air nozzle is approximately 60 ° C. Further, since the short nozzles 105 are attached to all the duct openings 33, the ratio that the air supplied from the central duct 29 dominates the temperature of the guarantee point is the lowest.

  Therefore, even when the temperature detected by the temperature sensors 31a and 31b is fed back to the temperature control unit 26 and enters a state where the set temperature is maintained at 60 ° C., there is a difference in the temperature of each guarantee point measured by the thermocouple. Come. The guarantee point having a higher temperature than the surroundings corresponds to a portion where the influence of the heat generation amount from each magnetic disk device 101 is large. In other words, a high-temperature guarantee point means that the amount of air blown from the short nozzle 105 is supplied to the magnetic disk device is smaller than other guarantee points. At the position of the duct opening 33 to which the short nozzle 105 corresponding to such a guarantee point is attached, it is considered that the internal pressure of the central duct 29 is lower than the internal pressure of the position of the other duct opening 33.

  Therefore, in block 213, the air nozzle corresponding to the high temperature guarantee point is replaced from the short nozzle 105 to the long nozzle 103, and the amount of air supplied from the central duct 29 to the guarantee point is increased. As a result, the temperature dominance due to the air flow from the central duct 29 can be increased with respect to the guarantee point where the temperature is high. Even if the short nozzle 105 is replaced with the long nozzle 103, the amount of air blown out from the long nozzle blowout port 119 is almost the same as the amount of air blown out from the blowout port 121 of the short nozzle 105. There is no change in the amount of air blown from the air nozzle attached to the duct opening 33, and the overall air flow can be easily adjusted.

  By replacing the air nozzles at the high-temperature guarantee points with the long nozzles 103 in order, the amount of air for each guarantee point approaches a uniform direction, and the temperature variation Δt between the guarantee points is reduced. be able to. Even if the amount of air supplied to each guarantee point can be made completely uniform, if there is a difference in the amount of heat generated by each magnetic disk device 101 in the actual operation test, there will be a temperature difference between each guarantee point. Arise. However, since the adjustment of the air flow is performed by causing the magnetic disk device 101 to generate the maximum heat, the temperature difference generated between the respective guarantee points during the actual operation test in which the heat generation amount is smaller than this is adjusted. Therefore, the temperature at each guarantee point in the actual operation test is guaranteed.

  Even if the set temperature of the test chamber 10 is changed to various values such as 55 ° C, 50 ° C, etc., if the Δt in the adjustment stage is within the allowable temperature range of the test temperature, the temperature of all guarantee points is guaranteed. can do. If Δt does not fall within the allowable range of the test temperature even after following the above procedure, make a difference in the size of the duct opening of the central duct 29, change the cross-sectional area of the air nozzle passage, Increase the capacity of the system. In one example, when Δt when the short nozzles 105 are attached to all the duct openings 33 is 5.3 ° C., if some of the air nozzles are replaced with the long nozzles 103 according to the procedure of FIG. It was possible to reach 6 ° C.

  So far, the test chamber for providing a high temperature environment has been described as an example. However, the test chamber of the present invention can also be configured as a test chamber for providing a low temperature environment. For example, a compressor and a heat exchanger are incorporated in the temperature adjustment units 21a and 21b in FIG. 3 to cool the air in the central duct 29. In this case, it is desirable to incorporate a dehumidifier to prevent condensation. The length of each air nozzle can be determined by a procedure similar to that shown in the flowchart of FIG.

  In addition, although the test chamber 10 is configured by using only two types of air nozzles, the long nozzle 103 and the short nozzle 105, the above-described air nozzles can be additionally employed by additionally using air nozzles having different lengths. Δt can be further reduced. Furthermore, if a telescopic air nozzle as shown in FIG. 6 is used, not only does it take time to replace the air nozzle, but the length of the air nozzle can be continuously changed. Further, Δt can be further reduced. In FIG. 6, the extendable nozzle 300 includes a movable nozzle 301 and a fixed nozzle 303. The inner wall of the movable nozzle 301 is configured to be able to slide in close contact with the outer wall of the fixed nozzle 303. After the movable nozzle 301 is slid with respect to the fixed nozzle 303 to adjust the amount of expansion and contraction, the movable nozzle 301 is fixed to the fixed nozzle 303 with a bolt 305. The slide position of the movable nozzle 301 with respect to the fixed nozzle 303 is determined with the goal of making the amount of air supplied to the magnetic disk device uniform.

  A blowout port 307 is formed in the movable nozzle 301, and a blowout port 309 is formed in the fixed nozzle 303. A base plate 311 is formed on the fixed nozzle 303 and can be attached to the duct opening 33 of the central duct 29 with a bolt. FIG. 6A shows a state where the movable nozzle 301 extends the longest, and FIG. 6B shows a state where the movable nozzle 303 contracts most. In the state of FIG. 6A, the outlet 309 of the fixed nozzle 303 is blocked by the wall of the movable nozzle 301. However, in the state of FIG. 6B, the outlet 309 is connected to the substrate 107 side through the outlet 307. Air can flow. The expandable / retractable air nozzle is not limited to the configuration illustrated in FIG. 6, and other structures such as a bellows type may be employed.

  Although the present invention has been described with the specific embodiments shown in the drawings, the present invention is not limited to the embodiments shown in the drawings, and is known so far as long as the effects of the present invention are achieved. It goes without saying that any configuration can be adopted.

  It can be used for a test chamber that houses a large number of heating elements.

1 is an external view of a test chamber 10 according to an embodiment of the present invention. FIG. 2 is a simplified front view of the inside of a test chamber. FIG. 2 is a simplified side view of the inside of a test chamber. It is the side view to which the magnetic disk apparatus and the air nozzle were expanded. It is a flowchart explaining the method to determine the length of an air nozzle. It is a figure explaining a telescopic air nozzle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Test chamber 11 Case 13 Front door 15, 17 Air intake port 19a, 19b Fan 21a, 21b Temperature adjustment unit 23a, 23b, 25a, 25b Air damper 26 Temperature control part 27 Test control apparatus 29 Central duct 30 Housing Portions 31a and 31b Temperature sensor 33 Duct opening 101 Magnetic disk device 103 Long nozzle 105 Short nozzle 107 Substrate 111 HDD holder 113 Interface connector 119, 121 Outlet

Claims (20)

A test chamber that houses a plurality of electronic devices and performs an operation test,
A storage section for storing the electronic device;
A central duct through which a plurality of duct openings are formed and through which airflow passes;
A fan that generates an air flow between the central duct and the housing;
A temperature adjustment unit for adjusting the temperature of the air flow generated by the fan;
A plurality of connectors capable of supplying power to each electronic device;
A test chamber having a plurality of air nozzles attached to the positions of the duct openings corresponding to the electronic devices and supplying air to the electronic devices.   The test chamber according to claim 1, wherein the plurality of electronic devices are magnetic disk devices.   3. The test chamber according to claim 2, wherein the blowout port is positioned so that air blown out from the blowout port of the air nozzle is directed to a base cover or a surface of the base parallel to the magnetic disk of the magnetic disk device. .   The test chamber according to claim 2, further comprising a test control device that communicates with the magnetic disk device.   3. The central duct extends vertically in the test chamber, and the magnetic disk device is arranged such that the surface of the magnetic disk is perpendicular to the front of the central duct. Test chamber.   The test chamber according to claim 1, wherein each of the air nozzles is detachably attached to the central duct.   The test chamber according to claim 1, wherein the plurality of air nozzles includes a long nozzle having a long flow path and a short nozzle having a short flow path.   The test chamber according to claim 7, wherein a blowout port of the long nozzle extends to a central portion of the magnetic disk device.   The test chamber according to claim 1, wherein the plurality of air nozzles are configured to be extendable.   The test chamber according to claim 9, wherein the air nozzle includes a fixed nozzle attached to the central duct and a movable nozzle attached to be slidable with respect to the fixed nozzle.   The test chamber according to claim 9, wherein a position of the movable nozzle with respect to the fixed nozzle is determined with a goal of uniforming an amount of air supplied to the electronic device.   The test chamber of claim 1, wherein the temperature adjustment unit includes a heater and the test chamber provides a high temperature environment.   The test chamber of claim 1, wherein the temperature adjustment unit includes a heat exchanger and a dehumidifier and the test chamber provides a low temperature environment.   The test chamber according to claim 1, wherein the central duct communicates with the top and bottom of the test chamber, and the fans are provided above and below the test chamber, respectively.   The test chamber according to claim 1, wherein a temperature sensor for controlling the temperature adjustment unit is installed in the vicinity of the electronic device.   The test chamber according to claim 1, wherein the minimum calorific value of the electronic device varies randomly within a range of 70% to 0% of the maximum calorific value during the operation test. A storage unit for storing electronic equipment, a central duct in which a plurality of duct openings are formed and an air flow passes, a fan for generating an air flow between the central duct and the storage unit, and the fan generated A temperature adjustment unit that adjusts the temperature of the air flow, a plurality of connectors that can supply power to the electronic devices, and the electronic devices that are attached to the duct openings corresponding to the electronic devices. In a test chamber comprising a plurality of air nozzles for supplying air to an instrument, a method for determining the length of the plurality of air nozzles,
Setting all of the plurality of air nozzles to a certain length so that the air nozzle outlet is farthest from each electronic device;
Connecting the electronic device to each of the connectors and operating all the electronic devices with maximum heat generation;
Measuring the temperature of a plurality of guarantee points set in the vicinity of each electronic device; and
Changing the length of the air nozzle according to the result of the measuring step.   The step of changing the length of the air nozzle includes the step of changing the air nozzle corresponding to a place where the temperature of the air nozzle corresponding to the place where the temperature measured at each guarantee point is high is lower than that. The determination method according to claim 17, further comprising a step of changing a length of the air nozzle so as to approach the electronic device from an outlet.   Each of the air nozzles can be attached to and detached from the central duct and is composed of a long nozzle having a long flow path and a short nozzle having a short flow path. The determination method according to claim 17, further comprising an attaching step. The determination method according to claim 17, wherein the air nozzle is configured to be extendable and the step of changing the length includes a step of changing an extension amount of the nozzle.

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