阅读说明：本技术 一种无霜双开门高低温试验机 (Frostless high and low temperature testing machine with double doors ) 是由 刘冬喜 于 2021-08-20 设计创作，主要内容包括：本发明涉及一种无霜双开门高低温试验机,包括箱体、设置在箱体内的试验舱、第一腔体、制冷装置,试验舱与第一腔体之间通过进风口和出风口连通,无霜双开门高低温试验机还包括干燥装置、加热装置、循环风机,箱体上还设置有两个箱门。上述试验机试验温度区间在-82～180℃,测试范围广,且能在低温下保持长时间运行,通过采用上述的箱体结构以及干燥装置,使得高低温试验机更便于线上应用,并且在实现双开门的情况下能够确保试验舱不会结霜,符合高精密工业领域对产品的老化测试要求。(The invention relates to a frostless double-door high-low temperature testing machine which comprises a box body, a test chamber, a first cavity and a refrigerating device, wherein the test chamber, the first cavity and the refrigerating device are arranged in the box body, the test chamber is communicated with the first cavity through an air inlet and an air outlet, the frostless double-door high-low temperature testing machine further comprises a drying device, a heating device and a circulating fan, and two box doors are further arranged on the box body. The testing temperature range of the testing machine is-82-180 ℃, the testing range is wide, the testing machine can keep running for a long time at low temperature, the high-temperature and low-temperature testing machine is more convenient to apply on line by adopting the box body structure and the drying device, the test chamber can be prevented from frosting under the condition of realizing double doors, and the requirement of the high-precision industrial field on the aging test of products is met.)

1. The utility model provides a frostless two high low temperature testing machines that open door, includes box (1), sets up test chamber (2) in box (1), through air intake and air outlet with first cavity (3) that test chamber (2) are linked together, right test chamber (2) carry out cooling device (4), with controlling means (11) that refrigerating device (4) are connected, its characterized in that: the frostless double-door high-low temperature testing machine further comprises a drying device (5) with an air inlet end connected with an air supply system and an air outlet end connected to the first cavity (3), a heating device (6) arranged in the first cavity (3) and used for adjusting the air temperature, and a circulating fan (7) used for enabling air in the test chamber (2) and the first cavity (3) to circularly flow through an air inlet and an air outlet, wherein the control device (11) is connected with the drying device (5), the heating device (6) and the circulating fan (7),

the box body (1) is at least provided with a first box wall, a second box wall and a third box wall, the first box wall and the second box wall are respectively provided with a box door (8) which can be opened/closed so as to enable the test chamber (2) to be communicated with/sealed from the outside, and the first cavity (3) is arranged on one side where the third box wall is arranged;

the drying device (5) comprises an air inlet (5-3) for compressed air to enter, a first drying tower (5-1), a second drying tower (5-2) and an air outlet (5-4) for dried compressed air to discharge, molecular sieves for drying the compressed air are arranged in the first drying tower (5-1) and the second drying tower (5-2), and one end of the first drying tower (5-1), one end of the second drying tower (5-2) and the air outlet (5-4) are communicated with each other;

the drying device (5) further comprises a control mechanism (5-5), the control mechanism (5-5) comprises a first switching device (5-6), a first exhaust hole (5-62) and a second exhaust hole (5-63) which are communicated with the outside, the first switching device (5-6) is provided with a first channel, two ends of the first channel are respectively connected with the other end of the first drying tower (5-1) and the other end of the second drying tower (5-2), a stop block (5-61) which is arranged in the first channel in a sliding mode and driven by air pressure, one end of the first channel connected with the first drying tower (5-1) is defined as a first end, one end of the first channel connected with the second drying tower (5-2) is defined as a second end, and the air inlet (5-3) is communicated with the middle of the first channel, the first end is also communicated with the first exhaust hole (5-62), and the second end is also communicated with the second exhaust hole (5-63); the control mechanism (5-5) has at least two working states and is switched by opening and closing the first exhaust hole (5-62) and the second exhaust hole (5-63);

when the first exhaust hole (5-62) is closed and the second exhaust hole (5-63) is opened, the control mechanism (5-5) is in a first working state, the stop block (5-61) abuts against the second end of the first channel, the air inlet (5-3) and the other end of the second drying tower (5-2) are blocked, the other end of the first drying tower (5-1) is communicated with the air inlet (5-3), the first drying tower (5-1) dries and outputs compressed air, and meanwhile the first drying tower (5-1) transmits the dried compressed air to the second drying tower (5-2) to dry molecular sieves in the second drying tower (5-2);

when the second exhaust hole (5-63) is closed and the first exhaust hole (5-62) is opened, the control mechanism (5-5) is in a second working state, the stop block (5-61) abuts against the first end of the first channel, the air inlet (5-3) and the other end of the first drying tower (5-1) are blocked, the other end of the second drying tower (5-2) is communicated with the air inlet (5-3), the second drying tower (5-2) dries and outputs the compressed air, and meanwhile the second drying tower (5-2) conveys the dried compressed air to the first drying tower (5-1) to dry the molecular sieve in the first drying tower (5-1).

2. The frostless double-door high-low temperature testing machine according to claim 1, characterized in that: each box door (8) is provided with an observation window (8-1), and the observation window (8-1) is provided with at least one operation opening (8-2) which enables the interior of the test chamber (2) to be communicated with the outside of the box body (1); the length and the width of the observation window (8-1) are both less than or equal to 1000mm, the thickness is less than or equal to 100mm, and the length, the width and the height of the test chamber (2) are both less than or equal to 1200 mm.

3. The frostless double-door high-low temperature testing machine according to claim 2, wherein: the outer side of the operation opening (8-2) is provided with a switchable closing cover (8-3), and when the closing cover (8-3) is closed, the closing cover (8-3) covers the operation opening (8-2).

4. The frostless double-door high-low temperature testing machine according to claim 2, wherein: the operation opening (8-2) is provided with splicing pieces (8-4) made of anti-static flexible materials, and the splicing connection structures formed among the splicing pieces (8-4) enable the interior of the test chamber (2) and the outside of the box body (1) to be isolated from each other.

5. The frostless double-door high-low temperature testing machine according to claim 1, characterized in that: the box body (1) further comprises a second cavity (9) and a third cavity (10), the second cavity (9) is arranged above the test chamber (2) and the first cavity (3), and the drying device (5) and the control device (11) are both located in the second cavity (9); the refrigerating device (4) is positioned in the third cavity (10), and the third cavity (10) is arranged below the test chamber (2) and the first cavity (3).

6. The frostless double-door high-low temperature testing machine according to claim 1, characterized in that: one end of the first drying tower (5-1), one end of the second drying tower (5-2) and the air outlet (5-4) are communicated with each other through a second switching device (5-7); the two ends of the second switching device (5-7) are respectively connected with one end of the first drying tower (5-1) and one end of the second drying tower (5-2), the middle part of the second switching device (5-7) is connected with the air outlet (5-4), a flow limiting ring (5-71) capable of being pushed by air flow to slide is arranged in the second switching device (5-7), and when the control mechanism (5-5) is in the first working state, the flow limiting ring (5-71) slides to one end of the second switching device (5-7) connected with the second drying tower (5-2); when the control mechanism (5-5) is in the second working state, the flow limiting ring (5-71) slides to one end of the second adapter device (5-7) connected with the first drying tower (5-1).

7. The frostless double-door high-low temperature testing machine according to claim 1, characterized in that: an upper filtering component (5-81), a lower filtering component (5-82) and a filling cavity (5-83) arranged between the upper filtering component (5-81) and the lower filtering component (5-82) are arranged in the first drying tower (5-1) and the second drying tower (5-2), the filling cavity (5-83) is used for filling molecular sieves, and a first clamping ring (5-84) used for fixing the upper filtering component is arranged between the upper filtering component (5-81) and the filling cavity (5-83); a second clamping ring (5-85) used for fixing the lower filter assembly is arranged between the lower filter assembly (5-82) and the filling cavity (5-83).

8. The frostless double-door high-low temperature testing machine according to claim 1, characterized in that: the control mechanism (5-5) further comprises a first control valve (5-51) for controlling the opening and closing of the first exhaust hole (5-62), and a second control valve (5-52) for controlling the opening and closing of the second exhaust hole (5-63).

9. The frostless double-door high-low temperature testing machine according to claim 8, wherein: the first control valve (5-51) and the second control valve (5-52) are electromagnetic valves.

Technical Field

The invention relates to the technical field of aging test instruments, in particular to a frostless double-door high-low temperature testing machine.

Background

In high-precision fields such as 5G communication, electrician electronics, aerospace, semiconductor chips and the like, before relevant products are put into the market, strict simulation tests need to be carried out on the products so as to verify the reliability of the products under high-temperature, low-temperature or alternating conditions. The high and low temperature testing machine is formal and commonly used reliability testing equipment.

The existing high-low temperature testing machines are all single-door testing machines, namely, a testing cabin is only provided with one openable cabin door, although high-low temperature testing machines with two cabin doors are available in the market, the number of the testing cabins is also two, and each testing cabin is still only provided with one cabin door, so that the so-called double-door high-low temperature testing machine is still single-door in nature. The high-low temperature testing machine with a single door is not convenient to apply on a production line and is not convenient for simultaneous operation of multiple people due to the limitation of the door opening position. However, if a plurality of doors are arranged in one test chamber, the sealing performance is reduced, external air enters the chamber to frost the chamber, the temperature in the test chamber is inaccurate and unstable, and the test result is affected.

Therefore, it is necessary to invent a high and low temperature testing machine which is convenient for on-line testing operation and can be frostless.

Disclosure of Invention

The invention aims to provide a frostless double-door high-low temperature testing machine.

In order to achieve the purpose, the invention adopts the technical scheme that:

the invention provides a frostless double-door high and low temperature testing machine, which comprises a box body, a testing chamber arranged in the box body, a first cavity communicated with the testing chamber through an air inlet and an air outlet, a refrigerating device for cooling the testing chamber, a control device connected with the refrigerating device, a drying device with an air inlet end connected with an air supply system and an air outlet end connected with the first cavity, a heating device arranged in the first cavity and used for adjusting the air temperature, a circulating fan used for enabling the air in the testing chamber and the first cavity to circularly flow through the air inlet and the air outlet, wherein the control device is connected with the drying device, the heating device and the circulating fan, the gas in the testing chamber circulates into the first cavity under the driving of the circulating fan and is heated by the heating device of the first cavity so as to adjust the temperature of the gas, the combined action of the refrigerating device and the heating device ensures that the air in the test chamber can keep constant at a lower temperature, the long-time operation of the testing machine at a low temperature is realized, the refrigerating temperature is as low as-82 ℃ and the high temperature can reach 180 ℃. Meanwhile, the drying device continuously conveys the dried compressed gas into the first cavity, even if a small amount of gas escapes from the operation port, the test chamber is always in a positive pressure state, and the external gas of the testing machine cannot enter the test chamber through the operation port, so that the test chamber and the observation window are ensured not to frost. The air supply system may be a device or system capable of supplying compressed air, such as a central air compression system at a production and manufacturing site.

The box body is at least provided with a first box wall, a second box wall and a third box wall, the first box wall and the second box wall are respectively provided with a box door which can be opened/closed so as to enable the test chamber to be communicated with/sealed from the outside, and the first cavity is arranged on one side where the third box wall is arranged; the arrangement of the two box doors enables the placing positions of the high-low temperature testing machine and the personnel operating positions during testing to be more flexible, and multiple people can operate simultaneously, so that online testing is facilitated.

Because the dew point, the service life and the connection structure of the common drying device can not meet the requirements of a high-low temperature testing machine, the drying device adopted by the invention comprises an air inlet for compressed air to enter, a first drying tower, a second drying tower and an air outlet for dried compressed air to discharge, molecular sieves for drying the compressed air are arranged in the first drying tower and the second drying tower, and one end of the first drying tower, one end of the second drying tower and the air outlet are communicated with each other; the drying device also comprises a control mechanism, the control mechanism comprises a first switching device, a first exhaust hole and a second exhaust hole which are communicated with the outside, the first switching device is provided with a first channel, two ends of which are respectively connected with the other end of the first drying tower and the other end of the second drying tower, and a stop block which is arranged in the first channel in a sliding mode and driven by air pressure, one end of the first channel, which is connected with the first drying tower, is defined as a first end, one end of the first channel, which is connected with the second drying tower, is defined as a second end, an air inlet is communicated with the middle of the first channel, the first end is also communicated with the first exhaust hole, and the second end is also communicated with the second exhaust hole; the control mechanism has at least two working states and is switched by opening and closing the first exhaust hole and the second exhaust hole; when the first exhaust hole is closed and the second exhaust hole is opened, the control mechanism is in a first working state, the stop block is abutted to the second end of the first channel, the air inlet and the other end of the second drying tower are blocked, the other end of the first drying tower is communicated with the air inlet, the first drying tower dries and outputs the compressed air, and meanwhile, the first drying tower conveys the dried compressed air to the second drying tower to dry the molecular sieve in the second drying tower; when the second exhaust hole is closed and the first exhaust hole is opened, the control mechanism is in a second working state, the stop block is abutted to the first end of the first channel, the other end of the air inlet and the other end of the first drying tower are blocked, the other end of the second drying tower is communicated with the air inlet, the second drying tower dries and outputs the compressed air, and meanwhile, the second drying tower conveys the dried compressed air to the first drying tower so as to dry the molecular sieve in the first drying tower. This drying device when can reuse reach regeneration, through the control mechanism who adopts above-mentioned structure, the maximize reduces solenoid valve use quantity, is difficult for ageing, damage for drying device's long service life, work efficiency is high, has greatly simplified the tube coupling structure simultaneously, reduces the cost, saves space. On the other hand, the air dew point temperature range of the drying device is as low as-80 ℃, so that the drying device can be suitable for the manufacturing of high-precision components and the drying treatment in the testing process in more high-precision fields such as 5G communication, chips, aerospace, rail transit and the like, and the bulkhead and the observation window of the testing cabin are ensured not to frost at low temperature.

Furthermore, each box door is provided with an observation window, at least one operation opening which enables the interior of the test chamber and the outside of the box body to be communicated is formed in each observation window, and the operation opening is formed in each observation window, so that the box door of the testing machine does not need to be opened during operation, a large amount of cooling air in the test chamber is prevented from increasing equipment energy consumption due to the fact that the box door of the testing machine is opened and escaped, and outside air enters the test chamber, and therefore frosting of the test chamber and the observation windows is avoided. Even if a small amount of air escapes from the operation port during operation, the air temperature in the test chamber is not affected; the length and width of the observation window are less than or equal to 1000mm and the thickness is less than or equal to 100mm, the length, width and height of the test chamber are less than or equal to 1200mm, and the high-low temperature testing machine can achieve frost-free performance within the size range. Compared with the prior art, the visual area of the observation window relative to the test chamber is enlarged as much as possible, the test condition in the test chamber is observed in an all-round and real-time manner, and frost-free and temperature in the chamber can be ensured.

Further, the outside of operation mouth is provided with the closing cap of switch, and when the closing cap was closed, the closing cap covered the operation mouth, has increased the leakproofness, prevents that test chamber and external world from carrying out air exchange in a large number.

Furthermore, the operation opening is provided with splicing pieces made of anti-static flexible materials, and the splicing type connecting structures formed among the splicing pieces enable the inside of the test chamber to be isolated from the outside of the box body. The splicing positions of the splicing pieces cannot be avoided to have certain gaps, so that the isolation does not completely isolate the interior of the test chamber from the outside, but blocks the connection position of the test chamber and the outside to a certain extent.

Furthermore, the box body also comprises a second cavity and a third cavity, the second cavity is arranged above the test cabin and the first cavity, and the drying device and the control device are both positioned in the second cavity; the refrigerating device is positioned in the third cavity, and the third cavity is arranged below the test cabin and the first cavity. The structural layout is set for the double door, and the double door is more reasonable.

Furthermore, one end of the first drying tower, one end of the second drying tower and the air outlet are communicated with each other through a second switching device; the two ends of the second switching device are respectively connected with one end of the first drying tower and one end of the second drying tower, the middle part of the second switching device is connected with the air outlet, a flow-limiting ring capable of being pushed by air flow to slide is arranged in the second switching device, and when the control mechanism is in a first working state, the flow-limiting ring slides to one end of the second switching device connected with the second drying tower; when the control mechanism is in the second working state, the flow limiting ring slides to one end of the second adapter device connected with the first drying tower. Under the effect of current-limiting ring, only make the drying tower that the small part compressed air can get into failure, and guarantee that most compressed air can discharge through the gas outlet and use to the high low temperature test box test in the first cavity, handled the drying tower that became invalid promptly, guaranteed the normal operating of high low temperature testing machine again, ensure that it reaches frostless, and not only primary and secondary is clear but also high-efficient.

Furthermore, an upper filtering component, a lower filtering component and a filling cavity arranged between the upper filtering component and the lower filtering component are arranged in the first drying tower and the second drying tower respectively, the filling cavity is used for filling the molecular sieve, and a first clamping ring used for fixing the upper filtering component is arranged between the upper filtering component and the filling cavity; and a second clamping ring for fixing the lower filtering component is arranged between the lower filtering component and the filling cavity. Because the inside molecular sieve of drying tower can be impacted by the air current and produce the tiny particle, and the tiny particle diffuses to first switching device and second switching device along with the air current, and dog and restriction ring that can lead to block when removing, and through setting up filter assembly, lower filter assembly, can prevent the emergence of this problem effectively. On the other hand, the drying effect can be ensured, and the frostless high-low temperature testing machine can be ensured when the low-temperature testing is carried out.

Further, the control mechanism further comprises a first control valve for controlling the opening and closing of the first air hole and a second control valve for controlling the opening and closing of the second air hole. Preferably, the first control valve and the second control valve are both solenoid valves.

Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages:

the frostless double-door high-low temperature testing machine has the advantages that the testing temperature interval is-82-180 ℃, the testing range is wide, the machine can keep running for a long time at low temperature, the high-low temperature testing machine is more convenient to apply on line by adopting the box body structure and the drying device, the test chamber can be prevented from frosting under the condition of realizing double doors, and the aging test requirement of the high-precision industrial field on products is met.

Drawings

Some specific embodiments of the invention will be described in detail hereinafter, by way of illustration and not limitation, with reference to the accompanying drawings. The same reference numbers in the drawings identify the same or similar elements or components. Those skilled in the art will appreciate that the drawings are not necessarily drawn to scale. In the drawings:

FIG. 1 is a schematic structural diagram of an embodiment of a frostless double-door high and low temperature tester in the invention;

FIG. 2 is an enlarged view of a portion of area A of FIG. 1;

FIG. 3 is a cross-sectional view of one embodiment of the frost-free double door high and low temperature testing machine of the present invention;

FIG. 4 is a schematic structural view of an embodiment of a drying device in the frostless double-door high and low temperature testing machine of the present invention;

FIG. 5 is a cross-sectional view of FIG. 4;

fig. 6 is a schematic view of the internal structure of a drying tower of the drying apparatus of fig. 4.

Wherein the reference numerals are as follows:

1. a box body; 2. a test chamber; 3. a first cavity; 4. a refrigeration device; 5. a drying device; 5-1, a first drying tower; 5-2, a second drying tower; 5-3, an air inlet; 5-4, air outlet; 5-5, a control mechanism; 5-51, a first control valve; 5-52, a second control valve; 5-6, a first switching device; 5-61, a stop block; 5-62, a first exhaust hole; 5-63 parts of a second exhaust hole; 5-7, a second switching device; 5-71, a flow-limiting ring; 5-81, an upper filter assembly; 5-82, a lower filter assembly; 5-83, filling the cavity; 5-84, a first snap ring; 5-85 parts of a second snap ring; 6. a heating device; 7. a circulating fan; 8. a box door; 8-1, an observation window; 8-2, an operation port; 8-3, closing the cover; 8-4, splicing sheets; 9. a second cavity; 10. a third cavity; 11. and a control device.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "first", "second", and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Referring to fig. 1 to 6, the frostless double-door high and low temperature testing machine in this embodiment includes a box 1, a test chamber 2 disposed in the box 1, a first cavity 3, a second cavity 9, and a third cavity 10, the test chamber 2 and the first cavity 3 are communicated through an air inlet and an air outlet, the second cavity 9 is disposed above the test chamber 2 and the first cavity 3, and the third cavity 10 is disposed below the test chamber 2 and the first cavity 3.

The box body 1 at least comprises a first box wall, a second box wall and a third box wall, wherein the first box wall and the second box wall are oppositely arranged, and the third box wall is located between the first box wall and the second box wall. The first cavity 3 is arranged on the side close to the third wall. And the first box wall and the second box wall are both provided with box doors 8, the test chamber 2 can be communicated with the outside by opening the box doors 8, and the test chamber 2 is sealed by closing the box doors 8. The arrangement of the two box doors 8 enables the placing positions of the high-low temperature testing machine and the personnel operating positions during testing to be more flexible, and multiple people can operate simultaneously, so that online testing is facilitated.

A heating device 6 for adjusting the air temperature and a circulating fan 7 for circulating the air in the test chamber 2 and the first cavity 3 are arranged in the first cavity 3.

This testing machine still includes refrigerating plant 4, the drying device 5, the controlling means 11 that carry out drying to the air that gets into first cavity 3 that carry out cooling to experimental cabin 2, and drying device 5, controlling means 11 all set up in second cavity 9, and refrigerating plant 4 sets up in third cavity 10. The control device 11 is connected with the refrigerating device 4, the drying device 5, the heating device 6 and the circulating fan 7. The air inlet end of the drying device 5 is connected with an air compression system/equipment at a production and manufacturing site, and the air outlet end of the drying device is connected with the first cavity 3. Under the drive of the circulating fan 7, the gas in the test chamber 2 circulates to the first cavity 3, the gas is heated by the heating device 6 of the first cavity 3 so as to adjust the temperature of the gas, the air in the test chamber 2 can be kept constant at a lower temperature under the combined action of the refrigerating device 4 and the heating device 6, the long-time operation of the testing machine at a low temperature can be realized, the refrigerating temperature can be as low as-82 ℃, and the high temperature can be as high as 180 ℃. Meanwhile, the drying device 5 continuously conveys the dried compressed gas into the first cavity 3 to enable the test chamber 2 to be in a positive pressure state all the time, so that constant low temperature can be kept in the test chamber 2, and the test chamber 2 is ensured not to frost.

The drying device in the prior art also can not satisfy the frostless test requirement of high low temperature testing machine, therefore this embodiment provides a low dew point and long service life, structure and is applicable to drying device. As shown in fig. 4 to 6, the drying device 5 in the present embodiment includes an air inlet 5-3 for compressed air to enter, a first drying tower 5-1, a second drying tower 5-2, and an air outlet 5-4 for dried compressed air to exit, wherein both the first drying tower 5-1 and the second drying tower 5-2 have a molecular sieve for drying compressed air, and one end of the first drying tower 5-1, one end of the second drying tower 5-2, and the air outlet 5-4 are communicated with each other. The drying device 5 also comprises a control mechanism 5-5, the control mechanism 5-5 comprises a first switching device 5-6, a first exhaust hole 5-62 and a second exhaust hole 5-63 which are communicated with the outside, the first switching device 5-6 is provided with a first channel, two ends of the first channel are respectively connected with the other end of the first drying tower 5-1 and the other end of the second drying tower 5-2, and a stopper 5-61 slidably disposed in the first passage and driven by air pressure, one end of the first passage connected to the first drying tower 5-1 being defined as a first end, one end of the first passage connected to the second drying tower 5-2 being defined as a second end, the air inlet 5-3 communicating with a middle portion of the first passage, the first end further communicating with the first exhaust hole 5-62, the second end further communicating with the second exhaust hole 5-63. The control mechanism 5-5 has at least two working states and is switched by the opening and closing of the first exhaust hole 5-62 and the second exhaust hole 5-63; when the first exhaust hole 5-62 is closed and the second exhaust hole 5-63 is opened, the control mechanism 5-5 is in the first working state, the stop block 5-61 is abutted to the second end of the first channel, so that the air inlet 5-3 and the other end of the second drying tower 5-2 are blocked, the other end of the first drying tower 5-1 is communicated with the air inlet 5-3, the first drying tower 5-1 dries and outputs the compressed air, and meanwhile, the first drying tower 5-1 transmits the dried compressed air to the second drying tower 5-2 so as to dry the molecular sieve in the second drying tower 5-2; when the second exhaust hole 5-63 is closed and the first exhaust hole 5-62 is opened, the control mechanism 5-5 is in the second working state, the stop block 5-61 is abutted to the first end of the first channel, so that the space between the air inlet 5-3 and the other end of the first drying tower 5-1 is blocked, the other end of the second drying tower 5-2 is communicated with the air inlet 5-3, the second drying tower 5-2 dries and outputs the compressed air, and meanwhile, the second drying tower 5-2 transmits the dried compressed air to the first drying tower 5-1 so as to dry the molecular sieve in the first drying tower 5-1.

The control mechanism 5-5 realizes the specific principle of the working state switching through the opening and closing of the first exhaust hole 5-62 and the second exhaust hole 5-63: in an initial state, taking a first working state as an example, as shown in fig. 5, the first exhaust hole 5-62 is closed, the second exhaust hole 5-63 is opened, the stopper 5-61 is located at the second end of the first channel, the compressed air flows into the first drying tower 5-1 through the first end of the first channel via the air inlet 5-3, and flows out through the air outlet 5-4 after being dried, and meanwhile, part of the dried air flows into the second drying tower 5-2 to dry the molecular sieve therein, and then is exhausted through the second exhaust hole 5-63. The air pressure at the other end of the first drying tower 5-1 (i.e., the bottom end of the first drying tower 5-1 shown in fig. 5) is greater than the normal atmospheric pressure due to the continuous air intake of the air intake port 5-3 and the obstruction of the air flow by the molecular sieves in the first drying tower 5-1; meanwhile, since the molecular sieve in the second drying tower 5-2 obstructs the air flow and the second exhaust hole 5-63 is communicated with the external atmosphere, the air pressure at the other end of the second drying tower 5-2 (i.e., the bottom end of the second drying tower 5-2 shown in fig. 5) is substantially equal to the normal atmospheric pressure, which results in that the air pressure at the left side of the stopper 5-61 is greater than the air pressure at the right side thereof (where the left side and the right side of the stopper 5-61 are defined as shown in fig. 5), thereby pressing the stopper 5-61 against the second end of the passage, and blocking the second drying tower 5-2, so that the compressed air cannot enter. During switching, the first exhaust hole 5-62 is opened, the second exhaust hole 5-63 is closed, and at the moment after switching, the first exhaust hole 5-62 is communicated with the outside atmosphere, so that the first drying tower 5-1 is instantly decompressed. Meanwhile, the airflow enters the second drying tower 5-2 from one end of the second drying tower 5-2 (i.e. the top end of the second drying tower 5-2 shown in fig. 5), so that the air pressure in the second drying tower 5-2 rises, and the air flow in the second drying tower 5-2 is stagnated due to the closing of the second exhaust hole 5-63, so that the air flow rate on the right side of the stopper 5-61 is close to 0, and the pressure difference is generated on the left and right sides of the stopper 5-61 due to the inverse proportion (bernoulli's theorem) of the air flow rate and the pressure generated thereby, so that the pressure on the right side is greater than the pressure on the left side thereof, and the stopper 5-61 slides leftwards to push to the first end of the first channel, and the bottom end of the first drying tower 5-1 is blocked. In the process that the stop block 5-61 is separated from the right side and moves leftwards, gas can enter the second drying tower 5-2 through the right side, but because the top end of the second drying tower 5-2 still has gas entering, and the molecular sieve in the second drying tower 5-2 blocks the gas flow, the gas pressure at the bottom end of the second drying tower 5-2 further rises, the gas flow rate at the right side of the stop block 5-61 is always smaller than that at the left side, so that the stop block 5-61 can move leftwards conveniently until the stop block 5-61 is tightly pressed at the first end of the first channel, and the bottom end of the first drying tower 5-1 is blocked. By adopting the control mechanism 5-5 with the structure, the drying device 5 can maximally reduce the using number of the electromagnetic valves while achieving regeneration through repeated utilization, has long service life, is not easy to age and damage, has high working efficiency, greatly simplifies a pipeline connecting structure, reduces cost, saves space, reduces the air dew point temperature range of the drying device to-80 ℃, and can meet the testing requirements of a high-low temperature testing machine on high-precision components in more high-precision fields such as 5G communication, chips, aerospace, rail transit and the like.

In a more preferred embodiment, the drying device 5 further comprises a second switching device 5-7, and one end of the first drying tower 5-1, one end of the second drying tower 5-2 and the air outlet 5-4 are communicated with each other through the second switching device 5-7, and particularly, as shown in fig. 4 and fig. 5, two ends of the second adapter 5-7 are respectively connected to one end of the first drying tower 5-1 and one end of the second drying tower 5-2, the middle of the second adapter 5-7 is connected to the air outlet 5-4, a flow-limiting ring 5-71 capable of being pushed by the air flow to slide is arranged in the second adapter 5-7, when the control mechanism 5-5 is in the first working state, the flow-limiting ring 5-71 slides to one end of the second adapter device 5-7 connected with the second drying tower 5-2; when the control mechanism 5-5 is in its second operating state, the restrictor ring 5-71 slides to the end of the second adapter 5-7 where it is connected to the first drying tower 5-1. Through setting up restrictor ring 5-71, only a small part gets into the drying tower that became invalid in the gas after making the drying, guarantees that most dry back gas is discharged to high low temperature test box test in first cavity 3 through gas outlet 5-4 and is used, has handled the drying tower that becomes invalid promptly, has guaranteed the normal operating of high low temperature test machine again, ensures that it reaches frostless, and is both primary and secondary clear and high-efficient. In addition, the second switching device 5-7 in this embodiment does not need to be controlled by a solenoid valve, and along with the change of the air flow direction of the first drying tower 5-1 and the second drying tower 5-2 after the switching of the working state of the control mechanism 5-5, the position of the flow limiting ring 5-71 is automatically changed by being pushed by the air flow, and in the process of switching the working state of the control mechanism 5-5, the flow limiting ring 5-71 does not cause any influence on the change of the air flow direction.

Preferably, as shown in fig. 6, an upper filter assembly 5-81, a lower filter assembly 5-82, and a filling cavity 5-83 disposed between the upper filter assembly 5-81 and the lower filter assembly 5-82 are disposed inside each of the first drying tower 5-1 and the second drying tower 5-2, the filling cavity 5-83 is used for filling molecular sieves, and a first snap ring 5-84 for fixing the upper filter assembly is disposed between the upper filter assembly 5-81 and the filling cavity 5-83; a second snap ring 5-85 for fixing the lower filter assembly is provided between the lower filter assembly 5-82 and the filling chamber 5-83. The molecular sieve can be limited in the drying tower by the internal structure of the drying tower, small particles generated by the impact of the airflow on the molecular sieve are prevented from being blocked when the stop block and the flow limiting ring move due to the fact that the small particles diffuse into the first switching device 5-6 and the second switching device 5-7 along with the airflow, normal operation of the device is guaranteed, and normal work of the high-low temperature test box is guaranteed. On the other hand, the problem of molecular sieve leakage is solved, so that the drying effect of the molecular sieve is ensured, and low dew point drying is kept, so that the frostless condition of the high-low temperature test box in the low-temperature test process is ensured.

Preferably, the control mechanism 5-5 controls the opening and closing of the first exhaust hole 5-62 and the second exhaust hole 5-63 through the first control valve 5-51 and the second control valve 5-52, respectively, in this embodiment, the first control valve 5-51 and the second control valve 5-52 are both solenoid valves, when the solenoid valve of the first control valve 5-51 is opened, the compressed air in the first drying tower 5-1 is exhausted from the first exhaust hole 5-62 to the outside, and when the solenoid valve is closed, the first exhaust hole 5-62 is closed. Similarly, when the solenoid valve of the second control valve 5-52 is opened, the compressed air in the second drying tower 5-2 is discharged to the outside through the second discharge hole 5-63, and when the solenoid valve is closed, the second discharge hole 5-63 is closed. The first exhaust holes 5-62 and the second exhaust holes 5-63 are respectively controlled by different devices, so that the accuracy of control operation is improved. In practical applications, the first control valve 5-51 and the second control valve 5-52 may be other devices or apparatuses capable of controlling the opening and closing of the exhaust hole in the prior art, and are not limited to solenoid valves. It can be seen that the drying device 5 in this embodiment requires only a maximum of two solenoid valves.

Preferably, as shown in fig. 2, each box door 8 is provided with an observation window 8-1, the length and width of each observation window 8-1 are less than or equal to 1000mm, the thickness of each observation window 8-1 is less than or equal to 100mm, and the length, width and height of the test chamber 2 are less than or equal to 1200 mm. Compared with the prior art, the visual area of the observation window 8-1 relative to the test chamber 2 is enlarged as much as possible, so that the test condition in the test chamber 2 can be observed in all directions and in real time, and frost-free and temperature in the chamber can be ensured. In practical application, the length and width of the observation window 8-1 should be increased along with the increase of the length, width and height of the test chamber, that is, the larger the size of the test chamber 2 is, the larger the observation window 8-1 is within a limited size range, so as to enlarge the visible area of the observation window 8-1 relative to the test chamber 2 as much as possible, so as to observe the test condition inside the test chamber 2 in an omnibearing and real-time manner, that is, the observation window 8-1 is a large window relative to the test chamber 2.

The observation window 8-1 is provided with at least one operation opening 8-2, the operation opening 8-2 is used for communicating the interior of the test chamber 2 with the exterior of the box body 1, and the object to be measured can be directly operated through the operation opening 8-2. The position of the operation port 8-2 on the observation window 8-1 is not limited. The operation opening 8-2 is formed in the box door 8, opening and closing of the box door 8 can be reduced, the box door 8 does not need to be opened in the test process, escape of cooling air in the test chamber 2 due to opening of the box door 8 is avoided, energy consumption is reduced, external air which is not dried is prevented from entering the test chamber 2, and frosting of the test chamber 2 and the observation window 8-1 is avoided. Even if a small amount of air escapes from the operation port 8-2 during operation, the air temperature in the test chamber 2 is not affected. It should be noted that, as described above, since the drying device 5 continuously delivers the dried compressed gas into the first chamber 3, even if a small amount of gas escapes from the operation opening 8-2, the test chamber 2 is always in a positive pressure state, and the external gas of the testing machine cannot enter the test chamber through the operation opening 8-2, so as to ensure that the test chamber and the observation window do not frost.

The operation opening 8-2 is provided with a plurality of splicing pieces 8-4 which are made of anti-static flexible materials in a splicing mode, when no operation action is carried out, the interior of the test chamber 2 is isolated from the outside of the box body 1 through the splicing pieces 8-4, but gaps are inevitably formed in the splicing positions of the splicing pieces 8-4, so that the interior of the test chamber 2 is not completely isolated from the outside through the isolation, the connection position of the test chamber 2 and the outside is blocked to a certain degree, and air in the test chamber 2 cannot escape outwards as much as possible.

The outer side of the operation opening 8-2 is provided with a closing cover 8-3 which can be opened and closed, the closing cover 8-3 can be opened to carry out operation through the operation opening 8-2, and after the operation is finished, the sealing cover 8-3 is closed, so that the sealing performance of the operation opening 8-2 is further improved.

The refrigerating device 4, the heating device 6 and the circulating fan 7 in this embodiment are devices that can achieve corresponding effects in the prior art, and therefore, the structures of these devices are not described in detail herein.

The frostless double-door high-low temperature testing machine in the embodiment has the advantages that the testing temperature range is-82-180 ℃, the testing range is wide, the high-low temperature testing machine can keep running for a long time at low temperature, the high-low temperature testing machine is more convenient to apply on line by adopting the box body structure and the drying device, the test chamber can be prevented from frosting under the condition of realizing double doors, and the requirement of the high-precision industrial field on the aging test of products is met.

The above embodiments are merely illustrative of the technical concept and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the content of the present invention and implement the invention, and not to limit the scope of the invention, and all equivalent changes or modifications made according to the spirit of the present invention should be covered by the scope of the present invention.