JPH04254738A - Controlling device of defrosting of apparatus for thermal shock test - Google Patents

Abstract

PURPOSE:To make the operation end time of a defrosting heater correspond to an optimum defrosting time and thereby to reduce a time loss by conducting a control of increasing and decreasing a working time of the defrosting heater on the basis of a set value of the required number of times of defrosting which is selected and set in accordance with each zone test. CONSTITUTION:The frost sticking to a cooler 10 of a low-temperature tank 3 in the process of a test is removed by a defrosting heater 12 under the control of CPU 18. Under the control of the CPU 18, in other words, a 2 zones/3 zones selection setting unit 17 determines a test zone set by a user. Based on this set zone, besides, a defrosting frequency setting unit 16 judges a defrosting frequency (DEF), i.e., the number of cycles of a test for defrosting at one time which is inputted by the user on the basis of the experience or the like, and decides on the time of electrification of the heater corresponding to each DEF. When the DEF is 50 or above, for instance, 30 minutes are set for a 2-zones test and 35 minutes for a 3-zones test. This time of electrification is determined beforehand by an experiment or the like as an optimum defrosting time for each DEF and set in a processing program. Accordingly, the outputted time of electrification is adequate for making the heater 12 operate and stop without any waste.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a thermal shock testing device for testing the characteristics of electrical and electronic components against heat stress by exposing them to high-temperature or low-temperature air. This invention relates to a death loss control device for a thermal shock testing device for efficient control.

0002

[Prior Art] A thermal shock test device is known, for example, from Japanese Patent Application Laid-Open No.
As shown in Publication No. 274035, the test chamber is configured with a high temperature chamber above and a low temperature chamber below, and the dampers provided in the test chamber are sequentially opened and closed to generate electricity in the high temperature chamber. high-temperature air generated in a cryostat and low-temperature air generated in a cryostat (in the case of a two-zone test), or alternatively, in addition to the above two types of air, room-temperature air may be supplied from outside the device. This is a device that tests the thermal stress characteristics of samples such as electrical and electronic components placed in a test chamber (in the case of a three-zone test).

[0003] In the above-mentioned apparatus, there is a problem that frost builds up inside the cryo-chamber while the above-mentioned thermal shock test is being continued. Temporarily suspended thermal shock test at Taimig.
Defrosting is performed. In this case, as a defrosting means, for example, the above-mentioned publication describes a device that defrosts by introducing warm air into the low temperature chamber from the outside, but generally a defrosting heater is used as a simpler device. It is widely used. The defrosting heater is provided near the refrigerator in the low temperature chamber, starts operating at a defrosting start time preset by the user, and stops operating after completing defrosting. By the way, with regard to the termination of this operation, there are two types: one in which the defrosting heater terminates the operation in a time determined by a timer, and the other in which the operation is terminated as appropriate when the temperature reaches the temperature detected by the temperature sensor. Among these, the object of the present invention is to terminate the operation using a timer, and this termination method has the advantage of being able to terminate the operation of the defrosting heater with a simpler structure and lower cost than when using a temperature sensor. There is.

0004

[Problem to be Solved by the Invention] However, the timer installed in the defrosting heater in this case operates the defrosting heater for a certain period of time from when it starts operating, regardless of the amount of frost formed or the temperature inside the tank. Therefore, for example, if the user sets the defrost start time to an early stage of the test, the defrost heater may continue to operate even though the amount of frost is small, just as it would be when the amount of frost is large. there were. As a result, there was a problem in that the interruption time for defrosting during the thermal shock test became extremely long, resulting in a large amount of lost time.

The present invention deals with this situation, and even when the defrosting heater is terminated by a timer, the timing at which the operation of the defrosting heater is terminated corresponds to the optimal defrosting time at that time, thereby reducing thermal shock. The purpose is to reduce loss time during exams.

[0006]

[Means for Solving the Problems] That is, the features of the present invention that meet the above object include a test chamber, a high temperature tank for generating and holding high temperature air, a low temperature tank for generating and holding low temperature air, and a test chamber for generating and holding low temperature air. There are two high-temperature dampers that allow air in and out of the high-temperature chamber to flow in and out to enable high-temperature exposure tests, and two high-temperature dampers that allow air in and out of the low-temperature chamber to flow in and out of the test chamber to enable low-temperature exposure tests.
and two room-temperature dampers that allow room-temperature air to flow in and out of the test chamber to enable a room-temperature exposure test, and a cooler for generating low-temperature air in the cryostat; In a thermal shock test device equipped with a defrosting heater that operates at predetermined intervals to defrost frost adhering to the cooler, three zones are formed in which one test cycle is formed by the low temperature exposure, room temperature exposure, and high temperature exposure. A test, a two-zone test in which one test cycle is formed from the low-temperature exposure and high-temperature exposure, and the required number of defrosts are selected and set, and the operating time of the defrost heater is increased or decreased based on each set value. It's about control. In addition, here, the number of times of defrosting is specifically 1.
The number of test cycles for each defrost test, that is, the number of cycles required to perform one defrost test, is used to express the defrost temperature. Set the operation start timing.

[0007]

[Function] The defrost control device with the above configuration allows the user to set each zone for a 2-zone test or a 3-zone test, and furthermore, when the number of defrosts at that time is set based on the user's experience, etc. On the other hand, the defrosting time for the set number of defrosts in the set zone is determined by the control device, and the defrosting heater ends its operation based on this defrosting time.

[0008] Therefore, the defrosting heater does not operate for an unnecessarily long time, and the interruption time for defrosting heater operation during the thermal shock test is shortened.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory cross-sectional view of a thermal shock test apparatus to which the defrost control device of the present invention is applied, in which a high temperature chamber (2) is arranged above a test chamber (1) and a low temperature chamber (3) is arranged below. There is.

The test chamber (1) and each tank (2), (3) are separated by a heat insulating wall (4), and each heat insulating wall (4) is equipped with opening/closing dampers (5A ), (5A
), (6A), (6A) openings (5B), (5
B), (6B), and (6B) are arranged.

[0012] Furthermore, openings (7B) and (7B) equipped with opening/closing dampers (7A) and (7A) are also provided on both sides of the test chamber (1).
) is provided.

A heater (8) and a high-temperature fan (9) are provided inside the high-temperature tank (2) to generate high-temperature air and direct the generated high-temperature air through the opening (5B).
) can be circulated to the test room (1). On the other hand, inside the low temperature tank (3), there is a cooler (10), a regenerator (11), and a defrost heater (12) to be described later.
A cooler (
The low temperature air generated in step 10) can be circulated and supplied to the test chamber (1).

[0014] Furthermore, on the side outside of the test chamber (1),
A room temperature fan (15) is attached so that outside room temperature air can be supplied into the test chamber (1) from the opening (7B) through the duct (14).

[0015] Note that each of the fans (9), (13), (
15) to supply each air to the test chamber (1), each of the dampers (5A) to (7A), that is, the high temperature tank (2
) side, the low-temperature damper (6A) installed on the low-temperature tank (3) side, and the normal-temperature damper (7A) installed on the outside. Air is alternately sent into the test chamber (1), and the above-described two-zone test with high-temperature air and low-temperature air, and the three-zone test with high-temperature air, room temperature air, and low-temperature air are performed.

By the way, while performing the thermal shock test in this way, frost gradually adheres to the cooler (10) part of the cryostat (3), but the defrost heater (10) installed in the cryostat (3) 12) is provided to defrost this frost, and is controlled by a defrost control device shown in block form in FIG. 2 as a feature of the present invention.

The defrost control device shown in FIG. 2 is equipped with a defrost frequency setting device (16) and a 2-zone or 3-zone selection setting device (17).
A CPU (18) is provided which calculates the defrosting time using each of the set values 6) and (17) as input values, and controls the operation of the defrosting heater (12) based on the calculation results. The CPU (
18) also simultaneously operates the high temperature damper (5A), room temperature damper (7A), and low temperature damper (5A) based on the input value.
6A), it also issues operation commands to the cooler (10) and heater (8), and also manages interruption of the thermal shock test during defrosting.

FIG. 3 is an example of a flowchart of a processing program for determining the defrosting time of the CPU (18). This flowchart will be explained below.
First, (T) indicates the defrosting time, specifically the defrosting heater (
12) represents the energization time. In (a), the energization time (T) is set to an initial value of 0. Then, in (b), it is determined whether the test zone set by the user is 2 zones or 3 zones, and if it is 3 zones,
As shown in (c), 5 (minutes) is added to the initial value. From now on, when performing a 3-zone test, the energization time (T) of the defrost heater (12) is always set to be 5 minutes longer than when performing a 2-zone test. This is because during a zone test, there is a large amount of room-temperature air entering from the outside, resulting in a large amount of frost formation, which requires a correspondingly longer defrosting time. Next, in (d) and below, the set number of defrost operations (DEF) is determined.

[0019] Set defrost number (DEF) in this case
As mentioned above, is input by the user using the defrost frequency setting device (16) based on experience, etc., and the value is that in a two-zone test, high temperature exposure and low temperature exposure are considered to be one test cycle. , in the case of a three-zone test, the number of test cycles required to start defrosting after repeating high temperature exposure, room temperature exposure, and low temperature exposure as one test site, i.e., one defrost. The number of test cycles for is used.

[0020] In (d), when the defrost count (DEF) is 50 or more, the process flow is (f).
The energization time (T) of the defrosting heater (12) is
The value obtained by adding 30 (minutes) to the above initial value, that is, 30 minutes in the case of a 2-zone test, and 3 minutes in the case of a 3-zone test.
It is decided in 5 minutes. Similarly, the number of defrosts (DE
When F) is less than 50, (E), (F), (G) in the figure
, (H), the times shown in (W), (E), (L), (N), and (R) are determined, respectively, according to the range of the defrost frequency (DEF) shown in (H).

[0021] Here, each of these defrost times (DEF
) determined according to the range of (ri), (nu), (ru),
The energizing time (T) in (E), (W), and (F) is as follows:
The optimum defrosting time for each defrost frequency (DEF) is determined in advance through experiments or the like and is set in the processing program. Therefore, the energization time (T) finally output in (Y) is such that the defrosting heater (12) is operated for an efficient time and then terminated.

Note that FIG. 3 shows the output results of the defrosting time with respect to the number of times of defrosting explained above. Figure 3 is a graph with the defrost time on the vertical axis and the number of defrosts on the horizontal axis. From the graph, it can be seen that the greater the number of defrosts (the greater the number of cycles for one defrost), the longer the defrost time becomes. I can see that Of course, this is because the amount of frost formation increases as the number of times of defrosting increases. Further, the rate of increase in the defrosting time is changed stepwise every time the number of defrosting operations increases by 10, considering ease of control. However, it goes without saying that the relationship between the number of times of defrosting and the rate of increase in defrosting time, or the difference in defrosting time due to the difference in test zones described above, is not limited to this example.

[0023]

[Effects of the Invention] As explained above, the present invention provides a thermal shock test device in which the distinction between a 3-zone test and a 2-zone test and the value of the required number of defrosts can be set in the defrost heater installed in the low temperature chamber. , is equipped with a defrost control device that increases or decreases the operating time of the defrost heater based on each set value, so the defrost heater is operated for the optimum defrosting time according to the required number of defrosts for each test zone. can be done. Therefore, the thermal shock test interruption test for defrosting can be shortened, not only loss time is reduced, but also power consumption for defrosting can be saved. Moreover, since it does not include a temperature sensor or the like to detect the completion of defrosting, the above effects can be achieved with a low cost and simple structure.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a thermal shock test device to which a defrost control device of the present invention is applied.

FIG. 2 is a block diagram illustrating the defrost control device of the present invention.

FIG. 3 is a flowchart showing the operation of the defrost control device of the present invention.

FIG. 4 is a graph showing the operation results of the defrost control device of the present invention.

[Explanation of symbols]

(1) Testing room (2) High temperature bath (3) Low temperature chamber (5A) High temperature damper (6A) Low temperature damper (7A) Room temperature damper (10) Cooler (12) Defrost heater

Claims (1)

[Claims] Claim 1: A test chamber (1), a high-temperature tank (2) that generates and holds high-temperature air, and a low-temperature tank (2) that generates and holds low-temperature air.
3), two high-temperature dampers (5A), (5A) that allow air from the high-temperature tank (2) to flow in and out of the test chamber (1) to perform a high-temperature exposure test, and the test chamber (1). There are two low temperature dampers (6A), (6A) that allow air to flow in and out of the low temperature chamber (3) to enable low temperature exposure tests, and two low temperature dampers (6A) that allow air at room temperature to flow in and out of the test chamber (1). Two room temperature dampers (7A), (7A) that enable room temperature exposure tests
and a cooler (10) for generating low-temperature air in the low temperature tank (3), and a defrosting heater that operates at predetermined time intervals to defrost frost attached to the cooler (10). (12
), a three-zone test in which one test cycle is formed by the low-temperature exposure, room temperature exposure, and high-temperature exposure, and a two-zone test in which one test cycle is formed by the low-temperature exposure and high-temperature exposure. defrost control of a thermal shock test apparatus, characterized in that the defrost control is configured to selectively set one of the tests and the required number of defrosts, and to increase/decrease the operating time of the defrosting heater based on each set value. Device.