High-vacuum low-temperature storage device

Abstract

The invention provides a high-vacuum low-temperature storage device. The high-vacuum low-temperature storage device comprises a main body, a cooling body and a sample conveying channel connected with the main body, a vacuum cavity is formed in the main body, the cooling body comprises a Dewar flask arranged in the vacuum cavity, the Dewar flask is filled with a cooling agent, a sample storage position is formed in the vacuum cavity, and the sample storage position is adjacent to the cooling body. The sample conveying channel is provided with an outer conveying opening and an inner conveying opening, the outer conveying opening is used for being connected with an external electron microscope sample conveying piece in a matched mode, and the inner conveying opening is communicated with the vacuum cavity and aligned to the sample storage position. Therefore, pollution to the sample in the conveying process is avoided. Samples are stored in the sample storage positions, so that the samples are ensured to be in a proper high-vacuum low-temperature environment, pollution and temperature rise to the samples in the storage process are avoided, the sample quality is ensured, the number of effective samples and the effective area of a single sample in the experiment process are increased, and smooth proceeding of subsequent data collection and high-resolution structural analysis is ensured.

Description

Technical Field

[0001] The present invention relates to the field of microscopic imaging technology, and in particular to a high vacuum and low temperature storage device. Background Art

[0002] In the field of microscopic imaging, cryo-electron microscopy is widely used. Cryo-electron microscopy uses rapid freezing or high-pressure freezing technology to freeze biological samples in a near-physiological state, preserving high-resolution structures. For cell tissue samples that are several microns or even thicker, they cannot be directly observed using a transmission electron microscope, and the samples need to be thinned. The currently commonly used sample thinning technology is to use cryo-focused ion beam technology, which uses a high-energy ion beam focused to a few nanometers to process the sample, and can obtain frozen biological thin slice samples within 200nm. With the development of automated cutting and fluorescence-assisted positioning technology, cryo-focused ion beam thinning has become an important technical means to study the in situ three-dimensional structure of cell tissues.

[0003] The sample can be ion-beam thinned in a dual-beam scanning electron microscope and then transferred to a transmission electron microscope for electron tomography data collection. The storage conditions for this type of sample are strict and must be kept below -150°C. In addition, the adsorption of ice crystals and other contaminants on the sample surface must be minimized. Samples that adsorb a large amount of contaminants will be damaged and cannot be used. Currently, this type of sample is stored in a liquid nitrogen tank before being transferred to a cryo-transmission electron microscope for imaging. During this storage process, the sample needs to be transferred multiple times, coming into contact with the water-containing atmosphere and liquid nitrogen containing small ice crystals, causing a certain degree of contamination of the sample. In addition, during storage in the liquid nitrogen storage tank, the liquid nitrogen inevitably contains ice crystals, causing a certain amount of small ice crystals to be adsorbed on the sample surface again, causing contamination. This greatly reduces the number of valid samples and the effective area on a single slice, affecting subsequent data collection and high-resolution structural analysis. Summary of the Invention

[0004] To address the problems existing in the prior art, according to one aspect of the present invention, a high-vacuum, low-temperature storage device is provided. The high-vacuum, low-temperature storage device comprises a main body, a cooling body, and a sample delivery channel connected to the main body. The main body has a vacuum chamber formed therein. The cooling body comprises a Dewar flask disposed within the vacuum chamber and filled with a coolant. A sample storage location is formed within the vacuum chamber and is disposed adjacent to the cooling body. The sample delivery channel comprises an outer delivery port and an inner delivery port. The outer delivery port is configured to engage with an external electron microscope sample delivery member, while the inner delivery port communicates with the vacuum chamber and is aligned with the sample storage location.

[0005] The high vacuum low temperature storage device provided by the present application realizes the transportation of samples by setting up a sample transportation channel. The transportation process is all in the sample transportation channel and the vacuum chamber, which can avoid contamination of the sample during the transportation process. The sample is stored in the sample storage position, and the cooling body ensures that the sample is in a high vacuum low temperature environment (for example, the temperature is lower than -150°C, and the vacuum degree is better than 5×10 -3 Pa) to avoid contamination of samples during storage. This prevents sample contamination, ensures sample quality, increases the number of effective samples during the experiment and the effective area of each sample, and ensures smooth subsequent data collection and high-resolution structural analysis.

[0006] Exemplarily, the sample delivery channel includes a first delivery channel extending in a horizontal direction, the inner delivery port includes a first inner delivery port located on the side wall of the main body, the outer delivery port includes a first outer delivery port located on the outside of the main body, the sample delivery member includes a sample delivery rod, and the first outer delivery port is used to cooperate with the sample delivery rod.

[0007] Illustratively, a mounting plate is provided at one end of the first conveying channel away from the first inner conveying port, the first outer conveying port is opened on the mounting plate, a positioning column is provided on the mounting plate for adapting to the positioning hole of the sample conveying rod, a fixing claw is also connected to the mounting plate, at least part of the structure of the sample conveying rod is clamped between the fixing claw and the mounting plate, a sample pre-pumping channel is provided on the mounting plate, and the sample pre-pumping channel is connected to a pre-vacuum pump.

[0008] Illustratively, a turntable assembly rotatable relative to the Dewar flask is provided at the bottom of the Dewar flask. The turntable assembly includes a rotating motor, a rotating table and a transmission table. The output end of the rotating motor is connected to the transmission table and drives the rotating table to rotate through the transmission table. A plurality of sample storage positions are formed on the rotating table along the rotation direction. The sample storage positions are used to place the first sample holder.

[0009] Exemplarily, a blocking cover is provided at the bottom of the Dewar flask, which includes a top cover in contact with the bottom of the Dewar flask and a side cover extending downward along the outer edge of the top cover. Multiple sample storage positions are located on the inner side of the side cover, and a connecting port is provided on the side cover corresponding to the first inner conveying port. A first hollow structure is provided at the center of the rotating table, and a second hollow structure is provided at the center of the top cover. A protrusion is provided at the bottom of the Dewar flask, and the protrusion extends into the first hollow structure and the second hollow structure.

[0010] Exemplarily, the sample delivery channel includes a second delivery channel extending in a vertical direction, the inner delivery port includes a second inner delivery port located on the bottom wall of the main body, the outer delivery port includes a second outer delivery port located on the outside of the main body, the sample delivery part includes a liquid nitrogen cup, the second outer delivery port is used to cooperate with the liquid nitrogen cup for connection, the high vacuum low temperature storage device includes a frame, the main body is arranged on the frame, an elastic component is provided on the frame, and the liquid nitrogen cup is installed above the elastic component.

[0011] Illustratively, a movable arm movable in a vertical direction relative to the main body is provided in the vacuum chamber, and a grabbing member for grabbing the second sample holder is provided at the bottom of the movable arm. The grabbing member extends into or out of the liquid nitrogen cup under the drive of the movable arm, and the grabbing member includes a clamping claw for clamping into the groove of the second sample holder and a blocking limit member for blocking the slot of the second sample holder.

[0012] Exemplarily, a push member is further provided in the vacuum chamber. When the second sample holder is moved to the sample storage position driven by the grabbing member, the push member moves and clamps the second sample holder between the push member and the cooling body.

[0013] Exemplarily, the cooling body further includes an extension block arranged on the side of the Dewar flask, and the sample storage position is formed on the side of the extension block away from the Dewar flask. When the second sample holder moves to the sample storage position driven by the gripping member, the pushing member moves and clamps the second sample holder between the pushing member and the extension block.

[0014] Exemplarily, an isolation valve is provided on the side of the sample delivery channel close to the main body, and the opening and closing of the isolation valve is used to realize the connection and disconnection between the sample delivery channel and the vacuum chamber. The main body is also connected to a vacuum pump group, which includes a mechanical pump and a molecular pump. The mechanical pump is connected to the molecular pump, and the molecular pump is connected to the vacuum chamber.

[0015] The Summary of the Invention introduces a series of simplified concepts that will be further described in detail in the Detailed Description of the Invention. This Summary of the Invention is not intended to limit the key features and essential features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0016] The advantages and features of the present invention are described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The following drawings of the present invention are hereby incorporated into the present invention for understanding the present invention. The drawings show embodiments of the present invention and their descriptions, and are used to explain the principles of the present invention. In the drawings,

[0018] Figure 1 is a perspective view of a high vacuum and low temperature storage device according to an exemplary embodiment of the present invention;

[0019] Figure 2 A cross-sectional view of a high vacuum low temperature storage device and a first sample holder according to an exemplary embodiment of the present invention;

[0020] Figure 3 A perspective view of a turntable assembly, a barrier cover, and a first sample holder according to an exemplary embodiment of the present invention;

[0021] Figure 4 A perspective view of a high vacuum low temperature storage device and a liquid nitrogen cup according to an exemplary embodiment of the present invention;

[0022] Figure 5 is a cross-sectional view of a high vacuum low temperature storage device, a liquid nitrogen cup, and a second sample holder according to an exemplary embodiment of the present invention;

[0023] Figure 6 A perspective view of a partial structure of a high vacuum low temperature storage device, a liquid nitrogen cup, and a second sample holder according to an exemplary embodiment of the present invention;

[0024] Figure 7 is a perspective view of a high vacuum and low temperature storage device according to an exemplary embodiment of the present invention;

[0025] Figure 8 4 is a perspective view of a high vacuum and low temperature storage device according to an exemplary embodiment of the present invention.

[0026] The above drawings include the following reference numerals:

[0027] 10. High-vacuum, low-temperature storage device; 110. Main body; 1101. Vacuum chamber; 1102. Sample storage position; 1110. Turntable assembly; 1111. Turntable; 1112. Rotating motor; 1113. Transmission platform; 1120. Enclosure cover; 1121. Top cover; 1122. Side cover; 1123. Connecting port; 120. Cooling element; 1210. Protrusion; 1220. Extension block; 130. Sample delivery channel; 1310. First delivery channel; 1311. First outer delivery port; 1312. First inner delivery port; 1313. Mounting plate; 131 4. Positioning column; 1315. Fixed claw; 1316. Sample pre-pumping channel; 1320. Second delivery channel; 1321. Second outer delivery port; 1322. Second inner delivery port; 1323. Sealing installation structure; 1330. Sample pre-pumping channel; 140. Frame; 1410. Elastic component; 1510. Moving arm; 1520. Grabbing member; 1521. Clamping claw; 1522. Blocking and limiting member; 1530. Lead screw; 160. Pushing member; 170. Isolation valve; 180. Molecular pump; 20. Liquid nitrogen cup; 30. Second sample holder; 40. First sample holder. DETAILED DESCRIPTION

[0028] In the following description, a large amount of detail is provided to facilitate a thorough understanding of the present invention. However, it will be appreciated by those skilled in the art that the following description merely illustrates preferred embodiments of the present invention, and that the present invention may be practiced without one or more of these details. Furthermore, to avoid confusion with the present invention, some technical features well known in the art have not been described in detail.

[0029] To provide a thorough understanding of the embodiments of the present invention, a detailed description of the structure will be provided in the following description. It should be understood that the implementation of the embodiments of the present invention is not limited to the specific details familiar to those skilled in the art. Preferred embodiments of the present invention are described in detail below, but in addition to these detailed descriptions, the present invention may also have other embodiments.

[0030] The embodiment of the present invention provides a high vacuum low temperature storage device. The high vacuum low temperature storage device can be used to store frozen samples, such as frozen section samples. Figure 1 、 Figure 2 、 Figure 4 、 Figure 7 and Figure 8 The high vacuum low temperature storage device 10 includes a main body 110, a cooling body 120, and a sample delivery channel 130 connected to the main body 110. A vacuum chamber 1101 is formed in the main body 110, and the vacuum chamber 1101 is isolated from the external space. The cooling body 120 includes a Dewar flask arranged in the vacuum chamber 1101. The Dewar flask can be filled with a coolant, and the cooling body 120 is used to maintain the low temperature of the frozen sample. The Dewar flask contains any type of coolant. Specifically, the coolant can be liquid nitrogen. The Dewar flask can be a metal part, such as a copper metal part. A sample storage position 1102 is formed in the vacuum chamber 1101 and the sample storage position 1102 is arranged adjacent to the cooling body 120. The sample delivery channel 130 has an external delivery port and an internal delivery port. The external delivery port can be used to cooperate with an external electron microscope sample delivery member, and the internal delivery port can be connected to the vacuum chamber 1101 and aligned with the sample storage position 1102. The sample storage position 1102 and the inner delivery port can be arranged adjacent to each other or at a certain distance. The cooling body 120 can maintain the temperature of the sample storage position 1102 below -150°C. The sample storage position 1102 can be used to store samples. It should be noted here that frozen samples are usually located in the sample holder. When referring to the sample holder below, it refers to the sample holder and the sample located in the sample holder. The sample storage position 1102 can be set accordingly according to the use requirements. For example, if the sample holder needs to be supported, the sample storage position 1102 is formed on a supporting platform (such as Figure 2 ), or, the sample storage location 1102 may not be carried by an entity, and may be understood as just a space (such as Figure 4). The sample storage position 1102 is arranged adjacent to the cooling body 120, so that the sample holder and the sample storage position are tightly fitted to better ensure that the sample holder is in a low-temperature environment. When it is necessary to transport the sample to the high vacuum low-temperature storage device 10, the electron microscope sample transport part is connected with the external transport port, and the sample enters through the sample transport channel 130 (the transportation process of the sample is related to the type of electron microscope sample transport part. The sample can be moved by the movable arm 1510 or the push rod of the electron microscope sample transport part. The specific movement method is described in detail below) into the vacuum chamber 1101. Since the internal transport port is aligned with the internal transport port, that is, after being moved out of the sample transport channel 130, the sample can directly reach the sample storage position 1102 for storage. Similarly, when it is necessary to take the sample out of the high vacuum low-temperature storage device 10, similar to the transport process, the sample is moved from the sample storage position 1102 to the external transport port by the push rod or the movable arm 1510 until the sample enters the corresponding electron microscope sample transport part.

[0031] The high vacuum low temperature storage device 10 provided by the present application realizes the transportation of samples through the provision of the sample transportation channel 130. The transportation process is all in the sample transportation channel 130 and the vacuum chamber 1101, which can avoid contamination of the sample during the transportation process. The sample is stored in the sample storage position 1102, and the cooling body 120 ensures that the sample is in a high vacuum low temperature environment (temperature below -150°C, vacuum degree better than 5×10 -3 Pa, and with a shielding device) to prevent contamination of samples during storage. This prevents sample contamination, ensures sample quality, increases the number of effective samples during the experiment and the effective area of each sample, and ensures smooth subsequent data collection and high-resolution structural analysis.

[0032] For example, with reference to Figure 1 、 Figure 2 and Figure 3The sample delivery channel 130 may include a first delivery channel 1310 extending horizontally, an inner delivery port may include a first inner delivery port 1312 located on the side wall of the main body 110, and an outer delivery port may include a first outer delivery port 1311 located on the outside of the main body 110. The sample delivery member may include a sample delivery rod, and the first outer delivery port 1311 may be used to cooperate with the sample delivery rod. The sample delivery rod is a frozen sample delivery rod commonly used in scanning electron microscopes on the market. The sample delivery rod is usually provided with a push rod, and the sample holder includes a first sample holder 40. The first sample holder 40 is disposed in the storage cavity of the sample delivery rod, and the push rod pushes the first sample holder 40 to move. The horizontally extending first delivery channel 1310 can better cooperate with the sample delivery rod. In an embodiment equipped with a pre-vacuum pump, isolation valve 170, fixing claw 1315, and mounting plate 1313, the movement process of the first sample holder 40 can be as follows: the sample transfer rod is connected to the mounting plate, the sample transfer rod is clamped by the clamping claw 1315, the pre-vacuum valve is opened, and the first transfer channel 1310 is pre-vacuumed by the pre-vacuum pump. Then, the pre-vacuum valve is closed, the isolation valve 170 is opened, and the valve on the transfer rod is opened. After pushing the first sample holder 40 through the first inner transfer port 1312, the first sample holder 40 can be directly pushed to the sample storage position 1102. The provision of the first transfer channel facilitates sample transfer between the high-vacuum low-temperature storage device 10 and the scanning electron microscope. The scanning electron microscope can be of any type, for example, a cryo-dual-beam scanning electron microscope.

[0033] For example, with reference to Figure 1 、 Figure 2 、 Figure 7 and Figure 8A mounting plate 1313 may be provided at one end of the first delivery channel 1310 away from the first inner delivery port 1312. The first outer delivery port 1311 is formed on the mounting plate 1313. A positioning post 1314 may be provided on the mounting plate 1313 to mate with the positioning hole of the sample delivery rod. Typically, one end of the sample delivery rod is a plate-like structure, with the positioning hole provided therein. During installation, the plate-like structure of the sample delivery rod abuts against the mounting plate 1313, and the positioning post 1314 is inserted into the positioning hole, allowing for rapid positioning of the sample delivery rod and the first sample holder 40 therein, thereby improving the efficiency of the sample delivery process. For example, a fixing claw 1315 may be connected to the mounting plate 1313, and at least a portion of the sample delivery rod may be clamped between the fixing claw 1315 and the mounting plate 1313. A sample pre-evacuation channel 1316 may also be provided on the mounting plate 1313, which may be connected to a pre-vacuum pump. The pre-vacuum pump can pre-vacuum the first delivery channel 1310. Specifically, when the sample delivery rod is mounted on the mounting plate 1313, the fixing claws 1315 can abut against the plate-like structure of the sample delivery rod, clamping the plate-like structure between the mounting plate 1313 and the fixing claws 1315, further ensuring a secure connection between the sample delivery rod and the first delivery channel 1310.

[0034] For example, with reference to Figure 2 and Figure 3 , a turntable assembly 1110 rotatable relative to the Dewar flask may be provided at the bottom of the Dewar flask, and a plurality of sample storage positions 1102 may be formed on the turntable assembly 1110 along the direction of rotation, and the sample storage positions 1102 may be used to place the first sample holder 40. The plurality of sample storage positions 1102 are spaced apart from each other. By rotating the turntable assembly 1110, the first inner delivery port 1312 can be aligned with different sample storage positions 1102, that is, a plurality of samples can be placed in different sample storage positions 1102 respectively. In this way, the storage of multiple samples can be realized, and the storage capacity of the high vacuum low temperature storage device 10 can be improved. In some embodiments, such as Figure 7 The sample storage location 1102 may be disposed adjacent to a side wall of the Dewar flask.

[0035] For example, with reference to Figure 2 and Figure 3The bottom of the Dewar flask can be provided with a containment cover 1120. This cover 1120 can include a top cover 1121 that contacts the bottom of the Dewar flask and a side cover 1122 that extends downwardly from the outer edge of the top cover 1121. Multiple sample storage locations 1102 can be located inside the side cover 1122, and a communication port 1123 can be defined in the side cover 1122 corresponding to the first inner delivery port 1312. The containment cover 1120 is positioned over the turntable assembly 1110 and surrounds the multiple sample storage locations 1102, specifically, the first sample receptacle 40 within the sample storage locations 1102. The top cover 1121 contacts the bottom of the Dewar flask and conducts low temperatures to the side cover 1122, forming a low-temperature chamber within the containment cover 1120. The sample storage locations 1102 and the first sample receptacle 40 therein are located within the low-temperature chamber. This configuration effectively maintains a low-temperature environment for the first sample receptacle 40. The enclosure cover 1120 can absorb the impurity gas in the vacuum chamber 1101, effectively reducing the contamination of the sample by the impurity gas. Specifically, the turntable assembly 1110 can include a rotating motor 1112, a rotating table 1111 and a transmission table 1113. The output end of the rotating motor 1112 is connected to the transmission table 1113. The transmission table 1113 drives the rotating table 1111 to rotate. There are multiple sample storage positions 1102, and multiple sample storage positions 1102 are formed on the rotating table 1111 along the rotation direction. The rotating motor 1112 can drive the transmission table 1113 to rotate, and the transmission table 1113 drives the rotating table 1111 to rotate, so that different sample storage positions 1102 are exposed to the connecting port 1123 to facilitate sample transmission.

[0036] For example, with reference to Figure 2 and Figure 3 , the center of the rotating table 1111 may have a first hollow structure, the center of the top cover 1121 may be provided with a second hollow structure, the bottom of the Dewar flask may have a protrusion 1210, and the protrusion 1210 extends into the first hollow structure and the second hollow structure. The rotating motor 1112 may be connected to the bottom of the protrusion 1210. Exemplarily, a thermal insulation gasket may be provided between the protrusion 1210 and the rotating motor 1112. In this way, the protrusion 1210 extends into the low-temperature chamber, further ensuring the effect of low-temperature storage, and is used to connect and fix the rotating motor 1112 through the thermal insulation material.

[0037] For example, with reference to Figure 1 、 Figure 2 、 Figure 4 and Figure 7The main body 110 can be connected to a vacuum pump assembly to ensure a vacuum environment in the vacuum chamber 1101. For example, the vacuum pump assembly can include a molecular pump 180 and a mechanical pump. The mechanical pump is connected to the molecular pump 180, and the molecular pump 180 is connected to the vacuum chamber 1101. For example, the first delivery channel 1310 can be connected to a pre-vacuum pump via a pre-vacuum valve. The pre-vacuum pump can pre-vacuum the first delivery channel 1310 to ensure a vacuum environment in the first delivery channel 1310 during the sample transfer process.

[0038] Illustratively, the process of transporting a sample into the vacuum chamber 1101 through the first delivery channel 1310 can be as follows: the sample delivery rod, which is fixed with the sample, is connected to the first external delivery port 1311, the positioning post 1314 is inserted into the positioning hole, the sample delivery rod is abutted against the mounting plate 1313, and the sample delivery rod is locked by the fixing claw 1315; the pre-vacuum pump and the pre-vacuum valve are turned on to pre-vacuum the first delivery channel 1310; after the vacuum level in the first delivery channel 1310 exceeds a set value (e.g., 20 Pa), the pre-vacuum valve is closed, the isolation valve 170 is opened, and the first sample holder 40 is moved toward the sample storage position 1102 by the push rod. The first delivery channel 1310 can be connected to the sample injection pre-vacuum channel 1330, and the pre-vacuum pump is connected to the sample injection pre-vacuum channel 1330 through the pre-vacuum valve. When pre-vacuuming of the first delivery channel 1310 is required, the pre-vacuum pump is turned on and vacuums the first delivery channel 1310 through the pre-vacuum valve and the sample injection pre-vacuum channel 1330. In the present application, vacuuming the first delivery channel 1310 can be achieved through a pre-vacuum pump, a pre-vacuum valve, and the sampling pre-vacuum channel 1330 .

[0039] Similarly, the process of transporting the sample from the vacuum chamber 1101 outward through the first delivery channel 1310 can be as follows: the sample delivery rod is matched and connected with the first external delivery port 1311, the positioning column 1314 is inserted into the positioning hole, the sample delivery rod is abutted against the mounting plate 1313, and the sample delivery rod is locked by the fixing claw 1315; the pre-vacuum pump and the pre-vacuum valve are turned on to pre-vacuum the first delivery channel 1310. After the vacuum degree in the first delivery channel 1310 is better than the set value (for example, 20 Pa), the pre-vacuum valve is closed, the isolation valve 170 is opened, and the first sample holder 40 is moved outward from the sample storage position 1102 by the push rod of the sample delivery rod. After the first sample holder 40 is moved out, the isolation valve 170 is closed.

[0040] For example, with reference to Figure 4 、 Figure 5 and Figure 6The sample delivery channel 130 may include a second delivery channel 1320 extending vertically. The inner delivery port may include a second inner delivery port 1322 located on the bottom wall of the main body 110. The outer delivery port includes a second outer delivery port 1321 located on the outside of the main body 110. The sample delivery member may include a liquid nitrogen cup. The second outer delivery port 1321 is configured to mate with an external liquid nitrogen cup 20. The liquid nitrogen cup 20 is a commonly used transmission electron microscope sample delivery member. The sample holder includes a second sample holder 30, within which the sample is mounted. The second sample holder 30 is placed within the liquid nitrogen cup 20. The second delivery port can dock with the liquid nitrogen cup 20. A sealing mounting structure 1323 may also be provided at the second delivery port to ensure a seal between the high vacuum and low temperature storage device 10 and the liquid nitrogen cup 20 after docking. This arrangement facilitates the transfer of the second sample holder 30 between the high vacuum and low temperature storage device 10 and the transmission electron microscope. After transfer, the second sample holder 30 is positioned in the sample storage position 1102 to ensure effective low temperature storage. The provision of the second delivery channel 1320 facilitates sample transport between the high vacuum and low temperature storage device 10 and the transmission electron microscope. In this embodiment, the sample storage position 1102 can be located on the side of the cooling body 120. For example, the storage device 10 can include a frame 140, the main body 110 is disposed on the frame 140, and the frame 140 can be provided with an elastic component 1410. The liquid nitrogen cup 20 can be mounted above the elastic component 1410. In this way, the elastic component 1410 pushes against the liquid nitrogen cup 20, making the connection between the liquid nitrogen cup 20 and the second delivery channel 1320 more stable.

[0041] It should be noted that the high vacuum low temperature storage device 10 in the present application may only have the first conveying channel 1310 (eg Figure 1 and Figure 2 ), may only have a second delivery channel 1320 (such as Figure 4 and Figure 5 ), and may also have a first delivery channel 1310 and a second delivery channel 1320 (such as Figure 7 and Figure 8 ).

[0042] For example, with reference to Figure 5 and Figure 6A movable arm 1510 is provided in the vacuum chamber 1101 and is movable in the vertical direction relative to the main body 110. A gripping member 1520 is provided at the bottom of the movable arm 1510 for grabbing the second sample holder 30. The gripping member 1520 is driven by the movable arm 1510 to extend into or out of the liquid nitrogen cup 20. The second sample holder 30 is placed in the liquid nitrogen cup 20, and the gripping member 1520 can extend into the liquid nitrogen cup 20 to grab or release the second sample holder 30. In this way, the grabbing member 1520 is driven by the movable arm 1510, making the transfer process of the second sample holder 30 between the high vacuum low temperature storage device 10 and the transmission electron microscope more efficient. During the transfer process, the second sample holder 30 is isolated from the outside in the liquid nitrogen cup 20, the second transfer channel and the main body 110 to prevent the sample from being contaminated. For example, a lead screw 1530 can be provided in the main body 110 to drive the movable arm 1510 to move.

[0043] For example, with reference to Figure 4 and Figure 6 The grabbing member 1520 may include a clamping claw 1521 for clamping into the groove of the second sample holder 30 and a blocking and limiting member 1522 for blocking the slot of the second sample holder 30. The blocking and limiting member 1522 may include a blocking bar and limiting bars located on opposite sides of the blocking bar, and the limiting bars are used to abut against the side walls of the second sample holder 30 to limit the position. In this way, the grabbing member 1520 is guaranteed to be stable during the process of grabbing the second sample holder 30. During the movement of the second sample holder 30 in the second transmission channel, the liquid nitrogen cup 20 and the vacuum chamber 1101, the blocking and limiting member 1522 can reduce the contact between the sample and the outside, further preventing the sample from being contaminated.

[0044] For example, with reference to Figure 4 and Figure 6 A push-pull member 160 may also be provided in the vacuum chamber 1101. When the second sample holder 30 is moved to the sample storage position 1102 under the drive of the gripping member 1520, the push-pull member 160 moves and clamps the second sample holder 30 between the push-pull member 160 and the cooling body 120. The push-pull member 160 can move horizontally. In this way, the push-pull member 160 makes the second sample holder 30 stick to the cooling body 120, further ensuring that the second sample holder 30 is in a high vacuum and low temperature environment (temperature below -150°C, vacuum degree better than 5×10 -3 Pa). For example, the cooling body 120 may include an extension block 1220 disposed on the side of the Dewar flask, and the sample storage position 1102 may be formed on the side of the extension block 1220 away from the Dewar flask. When the second sample holder 30 is moved to the sample storage position 1102 by the gripping member 1520, the push member moves and sandwiches the second sample holder 30 between the push member 160 and the extension block 1220. The extension block 1220 may be a copper metal block.

[0045] For example, with reference to Figure 2 、 Figure 5 and Figure 8 , an isolation valve 170 is provided on one side of the sample delivery channel 130 close to the main body 110, and the connection and disconnection between the sample delivery channel 130 and the vacuum chamber 1101 is realized by opening and closing the isolation valve 170. It can be understood that, during storage, the isolation valve 170 is in a closed state to ensure the isolation of the vacuum chamber 1101 from the external environment. When the sample needs to be transported, the isolation valve 170 is opened to ensure smooth transportation of the sample. When the second delivery channel 1320 transports the sample, the second delivery channel 1320 is connected to the liquid nitrogen cup 20. In this usage scenario, dry nitrogen can be introduced into the vacuum chamber 1101, and then the isolation valve 170 is opened to transport the sample.

[0046] Illustratively, the process of transporting the sample into the vacuum chamber 1101 through the second delivery channel 1320 can be as follows: the liquid nitrogen cup with the second sample holder 30 placed thereon is connected to the second external delivery port 1321, and the liquid nitrogen cup 20 is firmly connected to the second external delivery port 1321 through the cooperation of the sealing mounting structure 1323 and the elastic component 1410. Dry nitrogen, for example, is introduced into the vacuum chamber 1101, the isolation valve 170 is opened, the movable arm 1510 drives the grabbing member 1520 to extend into the liquid nitrogen cup 20, the grabbing member 1520 grabs the second sample holder 30, and the movable arm 1510 drives the grabbing member 1520 to move the second sample holder 30 upward to the sample storage position 1102. The pushing member 160 pushes the second sample holder 30 so that the second sample holder 30 is attached to the Dewar flask.

[0047] Illustratively, the process of transporting the sample from the vacuum chamber 1101 to the outside through the second delivery channel 1320 can be as follows: through the cooperation of the sealing mounting structure 1323 and the elastic component 1410, the liquid nitrogen cup 20 is firmly connected to the second external delivery port 1321, the movable arm 1510 drives the grabbing part 1520 to the sample storage position 1102, and dry nitrogen is introduced into the vacuum chamber 1101. When the pressure in the vacuum chamber reaches atmospheric pressure, the isolation valve 170 is opened, and the grabbing part 1520 is driven by the movable arm 1510 to move the second sample holder 30 downward until the second sample holder 30 is placed in the liquid nitrogen cup 20. The movable arm 1510 moves upward, the isolation valve 170 is closed, and the vacuum pump group evacuates the vacuum chamber 1101.

[0048] For example, with reference to Figure 7 and Figure 8 In this embodiment, the main body 110 is connected to a first delivery channel 1310 and a second delivery channel 1320. In this way, the high vacuum and low temperature storage device 10 can be compatible with the electron microscope sample conveying parts of both the scanning electron microscope and the transmission electron microscope.

[0049] In the description of the present invention, it should be understood that the directions or positional relationships indicated by directional words such as "front", "back", "up", "down", "left", "right", "horizontal", "vertical", "vertical", "horizontal", "top", "bottom", etc. are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention; the directional words "inside" and "outside" refer to the inside and outside relative to the outline of each component itself.

[0050] For ease of description, area-relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the regional positional relationship between one or more components or features shown in the figures and other components or features. It should be understood that area-relative terms include not only the orientation of the components as described in the figures, but also different orientations in use or operation. For example, if the components in the drawings are inverted as a whole, the situation where the components are "above other components or features" or "above other components or features" will include the situation where the components are "below other components or structures" or "below other components or structures". Thus, the exemplary term "above" may include both the orientations "above" and "below". In addition, these components or features may also be positioned at other different angles (e.g., rotated 90 degrees or other angles), and this document is intended to include all of these situations.

[0051] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, parts, components and / or combinations thereof.

[0052] It should be noted that the terms "first," "second," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0053] The present invention has been described through the above-described embodiments. However, it should be understood that the above-described embodiments are for illustrative and illustrative purposes only and are not intended to limit the present invention to the described embodiments. Furthermore, it will be understood by those skilled in the art that the present invention is not limited to the above-described embodiments and that various variations and modifications may be made based on the teachings of the present invention, all of which fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high vacuum low temperature storage device, characterized in that: The invention comprises a main body, a cooling body and a sample delivery channel connected to the main body, wherein a vacuum cavity is formed in the main body, the cooling body comprises a Dewar flask arranged in the vacuum cavity, the Dewar flask is filled with a coolant, a sample storage position is formed in the vacuum cavity and the sample storage position is arranged adjacent to the cooling body, the sample delivery channel comprises an outer delivery port and an inner delivery port, the outer delivery port is used for cooperating and connecting with an external electron microscope sample delivery member, and the inner delivery port is communicated with the vacuum cavity and aligned with the sample storage position.

2. The high vacuum and low temperature storage device according to claim 1, characterized in that: The sample delivery channel includes a first delivery channel extending in a horizontal direction, the inner delivery port includes a first inner delivery port located on the side wall of the main body, the outer delivery port includes a first outer delivery port located on the outside of the main body, and the sample delivery member includes a sample delivery rod, and the first outer delivery port is used to cooperate with the sample delivery rod.

3. The high vacuum low temperature storage device according to claim 2, characterized in that: A mounting plate is provided at one end of the first delivery channel away from the first inner delivery port, the first outer delivery port is opened on the mounting plate, a positioning column for adapting to the positioning hole of the sample delivery rod is provided on the mounting plate, a fixing claw is further connected to the mounting plate, at least part of the structure of the sample delivery rod is clamped between the fixing claw and the mounting plate, a sample pre-pumping channel is provided on the mounting plate, and the sample pre-pumping channel is connected to a pre-vacuum pump.

4. The high vacuum low temperature storage device according to claim 2, characterized in that: A turntable assembly rotatable relative to the Dewar flask is provided at the bottom of the Dewar flask, and the turntable assembly includes a rotary motor, a rotary table and a transmission table. The output end of the rotary motor is connected to the transmission table and drives the rotary table to rotate via the transmission table. A plurality of sample storage positions are formed on the rotary table along the rotation direction, and the sample storage positions are used to place the first sample holder.

5. The high vacuum and low temperature storage device according to claim 4, characterized in that: The bottom of the Dewar flask is provided with a surrounding cover, which includes a top cover in contact with the bottom of the Dewar flask and a side cover extending downward along the outer edge of the top cover. The multiple sample storage positions are all located on the inner side of the side cover, and the side cover is provided with a connecting port corresponding to the first inner conveying port. A first hollow structure is provided at the center of the rotating table, and a second hollow structure is provided at the center of the top cover. A protrusion is provided at the bottom of the Dewar flask, and the protrusion extends into the first hollow structure and the second hollow structure.

6. The high vacuum low temperature storage device according to claim 1, characterized in that: The sample delivery channel includes a second delivery channel extending in a vertical direction, the inner delivery port includes a second inner delivery port located on the bottom wall of the main body, the outer delivery port includes a second outer delivery port located on the outside of the main body, the sample delivery part includes a liquid nitrogen cup, the second outer delivery port is used to cooperate with the liquid nitrogen cup for connection, the high vacuum low temperature storage device includes a frame, the main body is arranged on the frame, an elastic component is provided on the frame, and the liquid nitrogen cup is installed above the elastic component.

7. The high vacuum and low temperature storage device according to claim 6, characterized in that: A movable arm is provided in the high vacuum chamber and is movable in a vertical direction relative to the main body. A grabbing member for grabbing the second sample holder is provided at the bottom of the movable arm. The grabbing member extends into or out of the liquid nitrogen cup under the drive of the movable arm. The grabbing member includes a clamping claw for clamping into the groove of the second sample holder and a blocking limiter for blocking the slot of the second sample holder.

8. The high vacuum low temperature storage device according to claim 7, characterized in that: A push member is further provided in the high vacuum chamber. When the second sample holder is moved to the sample storage position under the drive of the grabbing member, the push member moves and clamps the second sample holder between the push member and the cooling body.

9. The high vacuum and low temperature storage device according to claim 8, characterized in that: The cooling body further includes an extension block provided on a side of the Dewar flask, and the sample storage position is formed on a side of the extension block away from the Dewar flask. When the second sample holder is moved to the sample storage position under the drive of the grabbing member, the pushing member moves and clamps the second sample holder between the pushing member and the extension block.

10. The high vacuum and low temperature storage device according to claim 1, characterized in that: An isolation valve is provided on the side of the sample delivery channel close to the main body, and the sample delivery channel and the vacuum chamber are connected and disconnected by opening and closing the isolation valve. The main body is also connected to a vacuum pump group, which includes a mechanical pump and a molecular pump. The mechanical pump is connected to the molecular pump, and the molecular pump is connected to the vacuum chamber.

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