Liquid nitrogen soaking test device

Abstract

The invention relates to the technical field of spacecraft performance tests, in particular to a liquid nitrogen soaking test device which comprises a soaking pool, a bearing frame, a Dewar flask and an air drying assembly, a test cavity is formed in the lower portion of the interior of the soaking pool, and an air drying cavity is formed in the upper portion of the interior of the soaking pool. The bearing frame is used for bearing a test piece. The bearing frame is arranged in the soaking pool in a manner of moving up and down so as to drive the test piece to move up and down; the Dewar flask is used for storing liquid nitrogen. And the Dewar flask is communicated with the test cavity and is used for supplying liquid nitrogen for soaking the test piece into the test cavity. The air drying assembly is installed in the air drying cavity and used for blowing nitrogen to the soaked test piece. After the test is completed, the test piece ascends along with the bearing frame and abuts against the air drying cavity. And the air drying assembly blows normal-temperature nitrogen to the soaked test piece so as to air the test piece, and the temperature of the test piece is gradually increased to the normal temperature. Therefore, the frosting phenomenon on the surface of the test piece when the test piece is separated from the liquid nitrogen soaking test device is effectively prevented.

Description

Technical Field

[0001] The present invention relates to the technical field of spacecraft performance testing, and in particular to a liquid nitrogen immersion testing device. Background Art

[0002] Deep space exploration refers to space exploration activities conducted on celestial bodies outside the earth. Through deep space exploration, humans can study the physical and chemical properties, dynamic characteristics, and surface topography of the measured celestial bodies, which is of great significance to human exploration of the origin and evolution of the earth and life. Unlike near-Earth space, deep space exploration will experience extreme thermal environments, such as ultra-low temperature environments. Therefore, on the ground, aerospace products are often immersed in liquid nitrogen immersion test devices to conduct ultra-low temperature storage tests to understand the ultra-low temperature comprehensive performance of the materials after manufacturing. However, when the test piece is separated from the liquid nitrogen immersion test device, frost is prone to occur on the surface.

[0003] Therefore, when the test piece is out of the liquid nitrogen immersion test device, how to prevent frost on the surface of the test piece becomes a technical problem that needs to be solved urgently by technical personnel in this field. Summary of the invention

[0004] In order to solve the problem of how to prevent frost from forming on the surface of a test piece when the test piece is separated from the liquid nitrogen immersion test device, the present invention provides a liquid nitrogen immersion test device.

[0005] A liquid nitrogen immersion test device is provided to achieve the purpose of the present invention, comprising:

[0006] An immersion tank, with a test chamber formed at the bottom and an air-drying chamber formed at the top;

[0007] The support frame is used to support the test piece; the support frame is arranged in the immersion tank so as to be movable up and down to drive the test piece to move up and down;

[0008] A Dewar flask is connected to the test chamber and is used to supply liquid nitrogen for immersing the test piece into the test chamber;

[0009] The air drying component is installed in the air drying chamber and is used to blow nitrogen gas to the test piece after immersion.

[0010] In some specific embodiments, the air-drying component includes:

[0011] The blast plate is installed on the inner wall of the air drying chamber; the blast plate is formed with ventilation holes;

[0012] The nitrogen gas supplier is connected to the vent hole on the blast plate and is used for supplying nitrogen gas.

[0013] In some of the specific embodiments, a liquid inlet communicating with the test chamber is provided at the bottom of the immersion tank;

[0014] Also includes:

[0015] Liquid level control mechanism; when the liquid level in the test chamber reaches a preset height, the liquid level control mechanism is used to isolate the liquid inlet and the test chamber.

[0016] In some specific embodiments, a guide groove is provided inside the side of the soaking tank where the liquid inlet is provided;

[0017] The liquid level control mechanism includes:

[0018] A floating block is disposed in the test chamber so as to be movable up and down;

[0019] A fixed pulley, rotatably mounted on the top of the test chamber;

[0020] A baffle is installed in the guide groove so as to be movable up and down;

[0021] A first traction bar, one end of which is connected to the floating block, and the other end of which is connected to the baffle;

[0022] When the float rises with the liquid level, the baffle plate descends to separate the liquid inlet from the test chamber; when the float falls with the liquid level, the baffle plate rises to connect the liquid inlet with the test chamber.

[0023] In some specific embodiments, the bottom of the immersion tank is also provided with a liquid outlet connected to the test chamber, and the top is provided with an exhaust port;

[0024] Also includes:

[0025] A liquid inlet pipe, one end of which is connected to the Dewar flask, and the other end of which is connected to the liquid inlet; a first electromagnetic switch valve and an electric proportional regulating valve are arranged on the liquid inlet pipe;

[0026] A liquid discharge pipe, one end of which is connected to the liquid outlet; a second electromagnetic switch valve is arranged on the liquid discharge pipe;

[0027] An exhaust pipe, one end of which is connected to the exhaust port; a third electromagnetic switch valve is arranged on the exhaust pipe;

[0028] In-place detection sensor, installed at the top of the test chamber, is used to detect whether the float is in place;

[0029] The controller is respectively connected with the in-position detection sensor, the first electromagnetic switch valve, the electric proportional regulating valve, the second electromagnetic switch valve, and the third electromagnetic switch valve.

[0030] In some specific embodiments, it also includes:

[0031] The lifting mechanism is installed on the top of the soaking tank and connected to the support frame to drive the support frame to move up and down.

[0032] In some specific embodiments, the lifting mechanism includes:

[0033] A drive motor is installed on the top of the immersion tank;

[0034] A winding drum, one end of which is fixedly connected to the output shaft of the driving motor;

[0035] One end of the second traction bar is wound on the winding drum, and the other end is connected to the supporting frame.

[0036] In some specific embodiments, it also includes:

[0037] The insulation board is installed in the immersion tank to separate the interior of the immersion tank into a test chamber and an air-drying chamber; the insulation board is provided with a first clearance hole;

[0038] A second give-way hole is provided on the top of the soaking pool.

[0039] In some specific embodiments, it also includes:

[0040] A first sealing cover is openably and closably disposed at the first clearance hole;

[0041] The second sealing cover is openably and closably arranged at the second clearance hole.

[0042] In some specific embodiments, it also includes:

[0043] The liquid nitrogen recovery tank is arranged below the immersion tank.

[0044] Beneficial effects of the present invention: The liquid nitrogen immersion test device of the present invention is provided with an immersion tank, a support frame, a Dewar flask and an air-drying component, and a test chamber is formed in the lower part of the interior of the immersion tank, and an air-drying chamber is formed in the upper part. The support frame is used to support the test piece. The support frame can be movably arranged in the immersion tank to drive the test piece to move up and down. The Dewar flask is used to store liquid nitrogen. The Dewar flask is connected to the test chamber and is used to supply liquid nitrogen for immersing the test piece into the test chamber. The air-drying component is installed in the air-drying chamber and is used to blow nitrogen gas to the test piece after immersion. After the test is completed, the test piece rises with the support frame and reaches the air-drying chamber. The air-drying component blows room temperature nitrogen gas to the test piece after immersion to air-dry the test piece and gradually heat the test piece to room temperature. In this way, frost on the surface of the test piece is effectively prevented when it is separated from the liquid nitrogen immersion test device. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a structural schematic diagram of some specific embodiments of a liquid nitrogen immersion test device of the present invention;

[0046] Figure 2 yes Figure 1 A partial enlarged view of the middle A area;

[0047] Figure 3 yes Figure 1 A partial enlarged view of area B.

[0048] In the attached drawings, 110, immersion tank; 111, test chamber; 112, air drying chamber; 113, liquid inlet; 114, guide groove; 115, liquid outlet; 116, exhaust port; 117, second clearance hole; 120, support frame; 130, Dewar flask; 140, air drying assembly; 150, liquid level control mechanism; 151, floating block; 152, fixed pulley; 153, baffle; 154, first traction bar; 161, liquid inlet pipe; 1611, first electric Magnetic switch valve; 1612, electric proportional control valve; 162, drain pipe; 1621, second electromagnetic switch valve; 163, exhaust pipe; 1631, third electromagnetic switch valve; 164, in-place detection sensor; 170, lifting mechanism; 171, drive motor; 172, winding drum; 173, second traction bar; 180, thermal insulation board; 181, first make way hole; 191, first cover; 192, second cover; 193, liquid nitrogen recovery pool. DETAILED DESCRIPTION

[0049] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0050] Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar symbols throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0051] In the description of the present invention, it is necessary to understand that the orientations or positional relationships indicated by the terms "top", "bottom", "inside", "outside", "axis", "circumferential", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention or simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0052] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0053] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix", "join", "hinge", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0054] As the background technology, aerospace products are often immersed in liquid nitrogen immersion test equipment on the ground to conduct ultra-low temperature storage tests to understand the ultra-low temperature comprehensive performance of the materials after manufacturing. However, when the test piece is out of the liquid nitrogen immersion test device, the surface is prone to frost. Therefore, when the test piece is out of the liquid nitrogen immersion test device, how to prevent frost on the surface of the test piece has become a technical problem that needs to be solved urgently by technicians in this field.

[0055] To improve the above problems, refer to Figure 1 , Figure 2 and Figure 3 , a liquid nitrogen immersion test device is provided, including an immersion tank 110, a support frame 120, a Dewar flask 130 and an air-drying assembly 140. A test chamber 111 is formed at the lower part of the interior of the immersion tank 110, and an air-drying chamber 112 is formed at the upper part. The support frame 120 is used to support the test piece. The support frame 120 is movably arranged in the immersion tank 110 up and down to drive the test piece to move up and down. The Dewar flask 130 is used to store liquid nitrogen. The Dewar flask 130 is connected to the test chamber 111, and is used to supply liquid nitrogen for immersing the test piece into the test chamber 111. The air-drying assembly 140 is installed in the air-drying chamber 112, and is used to blow nitrogen gas to the test piece after immersion.

[0056] The process and principle of the liquid nitrogen immersion test device are as follows:

[0057] First, the test piece is placed on the top surface of the support frame 120. Then, the test piece is lowered along with the support frame 120, passing through the air-drying chamber 112 and reaching the test chamber 111. In the test chamber 111, the test piece is soaked in liquid nitrogen to perform an ultra-low temperature storage test. After the test is completed, the test piece is raised along with the support frame 120 and reaches the air-drying chamber 112. Afterwards, the air-drying component 140 blows room temperature nitrogen to the soaked test piece to air-dry the test piece and gradually heat the test piece to room temperature. In this way, frost is effectively prevented from forming on the surface of the test piece when it is separated from the liquid nitrogen immersion test device.

[0058] Specifically, in the exemplary embodiment, the air-drying assembly 140 includes a blast plate and a nitrogen gas supplier. The blast plate is mounted on the inner wall of the air-drying chamber 112. A plurality of vents are formed on the blast plate. The nitrogen gas supplier is connected to the vents on the blast plate to supply nitrogen gas at room temperature. When the test piece reaches the air-drying chamber 112 from the test chamber 111, the nitrogen gas at room temperature flows through the vents and then flows to the test piece. Accordingly, an exhaust port 116 is provided at the top of the immersion tank 110 to allow nitrogen gas to flow out of the immersion tank 110.

[0059] Preferably, there are one, two or four blast plates. A plurality of vents are formed on each blast plate. When there is one blast plate, it is installed on one inner wall of the air-drying chamber 112. When there are two blast plates, they are installed on the inner walls of two sides of the air-drying chamber 112, and the test piece is blown from two sides of the test piece, thereby improving the efficiency of air drying and heating of the test piece. When there are four blast plates, they are installed on the inner walls of four sides of the air-drying chamber 112, and the test piece is blown from four sides of the test piece, thereby further improving the efficiency of air drying and heating of the test piece.

[0060] Specifically, in the example, Figure 1 , Figure 2 and Figure 3 As shown, a liquid inlet 113 connected to the test chamber 111 is provided at the bottom of the immersion tank 110. The liquid nitrogen immersion test device also includes a liquid level control mechanism 150. When the liquid level in the test chamber 111 reaches a preset height, the liquid level control mechanism 150 is used to separate the liquid inlet 113 from the test chamber 111. When the liquid level drops, the liquid level control mechanism 150 no longer separates the liquid inlet 113 from the test chamber 111, and liquid nitrogen can be replenished into the test chamber 111 through the liquid inlet 113. A guide groove 114 is provided inside the side of the immersion tank 110 where the liquid inlet 113 is provided. The liquid level control mechanism 150 includes a floating block 151, a fixed pulley 152, a baffle 153 and a first traction bar 154. The floating block 151 is movably provided in the test chamber 111. The fixed pulley 152 is rotatably mounted on the top of the test chamber 111. The baffle 153 is installed in the guide groove 114 so as to be movable up and down. The guide groove 114 can limit the moving direction of the baffle 153, thereby improving the smoothness of the operation of the liquid level control mechanism 150. One end of the first traction bar 154 is connected to the float 151, and the other end is connected to the baffle 153. When the liquid level in the test chamber 111 rises, the float 151 rises with the liquid level, and the baffle 153 descends in the guide groove 114 and reaches the connection between the liquid inlet 113 and the test chamber 111 to separate the liquid inlet 113 from the test chamber 111. When the liquid level in the test chamber 111 drops, the float 151 drops with the liquid level, and the baffle 153 rises in the guide groove 114 to connect the liquid inlet 113 with the test chamber 111. In this way, it is beneficial to automatically control the replenishment of liquid nitrogen, so that the liquid level of liquid nitrogen can always be maintained at a preset height to ensure that the test piece is immersed in liquid nitrogen throughout the entire process.

[0061] Specifically, in the example, Figure 1 and Figure 2 As shown, a liquid outlet 115 connected to the test chamber 111 is also provided at the bottom of the immersion pool 110. The liquid nitrogen immersion test device also includes a liquid inlet pipe 161, a liquid discharge pipe 162, an exhaust pipe 163, an in-place detection sensor 164 and a controller. One end of the liquid inlet pipe 161 is connected to the Dewar flask 130, and the other end is connected to the liquid inlet 113. The liquid nitrogen in the Dewar flask 130 can flow into the test chamber 111 through the liquid inlet pipe 161. A first electromagnetic switch valve 1611 and an electric proportional control valve 1612 are provided on the liquid inlet pipe 161. The first electromagnetic switch valve 1611 is used to control the on-off of the liquid inlet pipe 161. The electric proportional control valve 1612 is used to adjust the flow rate of liquid nitrogen in the liquid inlet pipe 161. One end of the liquid discharge pipe 162 is connected to the liquid outlet 115. The liquid nitrogen in the test chamber 111 can flow out of the test chamber 111 through the liquid outlet 115 and the liquid discharge pipe 162. A second electromagnetic switch valve 1621 is provided on the liquid discharge pipe 162. The second electromagnetic switch valve 1621 is used to control the on-off of the liquid discharge pipe 162. One end of the exhaust pipe 163 is connected to the exhaust port 116. A third electromagnetic switch valve 1631 is provided on the exhaust pipe 163. The third electromagnetic switch valve 1631 is used to control the on-off of the exhaust pipe 163. The in-place detection sensor 164 is installed on the top of the test chamber 111 through a fixed plate, and is used to detect whether the floating block 151 is in place. The controller is electrically connected to the in-place detection sensor 164, the first electromagnetic switch valve 1611, the electric proportional control valve 1612, the second electromagnetic switch valve 1621, the third electromagnetic switch valve 1631, and the gas nitrogen supplier. When liquid nitrogen needs to be added to the test chamber 111, the controller controls the first electromagnetic switch valve 1611 to open, and controls the opening of the electric proportional control valve 1612. When the float 151 contacts the in-place detection sensor 164 as the liquid level rises, the in-place detection sensor 164 sends an in-place signal to the controller, and the controller controls the first electromagnetic switch valve 1611 and the electric proportional control valve 1612 to close. When the liquid nitrogen in the test chamber 111 needs to be discharged, the controller controls the second electromagnetic switch valve 1621 to open. When nitrogen needs to be input into the air-drying chamber 112, the controller controls the nitrogen gas supplier to open and controls the third electromagnetic switch valve 1631 to open. Overall, the degree of automation is greatly improved.

[0062] Specifically, in the exemplary embodiment, the liquid nitrogen immersion test device further includes two lifting mechanisms 170. Both lifting mechanisms 170 are installed at the top of the immersion tank 110. The two lifting mechanisms 170 are respectively connected to the opposite sides of the support frame 120, and cooperate to drive the support frame 120 to move up and down to ensure the stability of lifting. Each lifting mechanism 170 includes a driving motor 171, a winding drum 172 and a second traction bar 173. The driving motor 171 is installed at the top of the immersion tank 110 and is electrically connected to the controller. One end of the winding drum 172 is fixedly connected to the output shaft of the driving motor 171. One end of the second traction bar 173 is wound on the winding drum 172, and the other end is connected to the support frame 120. The driving motor 171 can drive the winding drum 172 to rotate to release or reel the second traction bar 173, thereby driving the support frame 120 to descend or ascend, thereby driving the test piece to descend or ascend.

[0063] Specifically, in the exemplary embodiment, the liquid nitrogen immersion test device further includes a thermal insulation plate 180, a first cover 191, a second cover 192 and a liquid nitrogen recovery pool 193. The thermal insulation plate 180 is installed in the immersion pool 110 to isolate the interior of the immersion pool 110 into a test chamber 111 and an air-drying chamber 112. The thermal insulation plate 180 can effectively reduce the degree of mutual influence between the temperature in the test chamber 111 and the temperature in the air-drying chamber 112, thereby ensuring the test effect and the air-drying effect. A first clearance hole 181 is provided on the thermal insulation plate 180 for the support bracket 120 to be raised and lowered. A second clearance hole 117 is provided on the top of the immersion pool 110 for the support bracket 120 to be raised and lowered. The first cover 191 can be opened and closed at the first clearance hole 181. The second cover 192 can be opened and closed at the second clearance hole 117. After the test piece is placed on the top surface of the support bracket 120, the first cover 191 and the second cover 192 are opened. When the test piece reaches the test chamber 111, the first cover 191 and the second cover 192 are closed to isolate the air-drying chamber 112 from the outside and the test chamber 111 from the air-drying chamber 112, which can effectively reduce the volatilization of liquid nitrogen. Before the test piece is transferred from the test chamber 111 to the air-drying chamber 112, the first cover 191 and the second cover 192 are opened. After the test piece is transferred from the test chamber 111 to the air-drying chamber 112, the first cover 191 and the second cover 192 are closed to isolate the air-drying chamber 112 from the outside and the test chamber 111 from the air-drying chamber 112. When the test piece is transferred from the test chamber 111 to the outside of the immersion tank 110, the second cover 192 is opened. The liquid nitrogen recovery tank 193 is arranged below the immersion tank 110 to receive the liquid nitrogen flowing out of the drain pipe 162 for the purpose of recycling the liquid nitrogen.

[0064] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", "one specific embodiment" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0065] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solution and the inventive concept of the present invention within the scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A liquid nitrogen immersion test device, characterized in that: include: An immersion tank, with a test chamber formed at the bottom and an air-drying chamber formed at the top; A support frame, used for supporting the test piece; the support frame is arranged in the immersion tank so as to be movable up and down, so as to drive the test piece to move up and down; A Dewar flask, connected to the test chamber, and used for supplying liquid nitrogen for immersing the test piece into the test chamber; The air drying component is installed in the air drying chamber and is used to blow nitrogen gas to the test piece after immersion.

2. The liquid nitrogen immersion test device according to claim 1, characterized in that: The air-drying component comprises: A blast plate is installed on the inner wall of the air-drying chamber; a vent hole is formed on the blast plate; A nitrogen supplier is connected to the vent hole on the blast plate and is used to supply nitrogen.

3. The liquid nitrogen immersion test device according to claim 1, characterized in that: The bottom of the immersion tank is provided with a liquid inlet connected to the test cavity; Also includes: Liquid level control mechanism; when the liquid level in the test chamber reaches a preset height, the liquid level control mechanism is used to isolate the liquid inlet and the test chamber.

4. The liquid nitrogen immersion test device according to claim 3, characterized in that: A guide groove is provided inside the side of the soaking tank where the liquid inlet is provided; The liquid level control mechanism comprises: A floating block is disposed in the test chamber so as to be movable up and down; a fixed pulley rotatably mounted on the top of the test chamber; A baffle plate is installed in the guide groove so as to be movable up and down; A first traction bar, one end of which is connected to the floating block, and the other end of which is connected to the baffle; When the float rises with the liquid level, the baffle plate descends to separate the liquid inlet from the test chamber; when the float falls with the liquid level, the baffle plate ascends to connect the liquid inlet with the test chamber.

5. The liquid nitrogen immersion test device according to claim 4, characterized in that: The bottom of the immersion tank is also provided with a liquid outlet connected to the test chamber, and the top is provided with an exhaust port; Also includes: A liquid inlet pipe, one end of which is connected to the Dewar flask, and the other end of which is connected to the liquid inlet; the liquid inlet pipe is provided with a first electromagnetic switch valve and an electric proportional regulating valve; A liquid discharge pipe, one end of which is connected to the liquid outlet; a second electromagnetic switch valve is provided on the liquid discharge pipe; An exhaust pipe, one end of which is connected to the exhaust port; a third electromagnetic switch valve is provided on the exhaust pipe; An in-place detection sensor is installed at the top of the test chamber to detect whether the floating block is in place; The controller is respectively connected with the in-position detection sensor, the first electromagnetic switch valve, the electric proportional control valve, the second electromagnetic switch valve, and the third electromagnetic switch valve.

6. The liquid nitrogen immersion test device according to claim 1, characterized in that: Also includes: The lifting mechanism is installed on the top of the soaking tank and connected to the support frame to drive the support frame to move up and down.

7. The liquid nitrogen immersion test device according to claim 6, characterized in that: The lifting mechanism comprises: A driving motor is installed on the top of the soaking tank; A winding drum, one end of which is fixedly connected to the output shaft of the driving motor; One end of the second traction bar is wound around the winding drum, and the other end is connected to the supporting frame.

8. The liquid nitrogen immersion test device according to claim 1, characterized in that: Also includes: A thermal insulation board is installed in the soaking tank to separate the interior of the soaking tank into the test chamber and the air-drying chamber; a first clearance hole is opened on the thermal insulation board; A second clearance hole is provided on the top of the soaking pool.

9. The liquid nitrogen immersion test device according to claim 8, characterized in that: Also includes: A first sealing cover, which is openably and closably disposed at the first clearance hole; The second sealing cover is openably and closably arranged at the second evacuation hole.

10. The liquid nitrogen immersion test device according to claim 1, characterized in that: Also includes: The liquid nitrogen recovery tank is arranged below the immersion tank.

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