Sample carrier storage rack for continuous sectioning transmission electron microscopy imaging

Abstract

A sample carrier storage rack for continuous sectioning transmission electron microscopy imaging. Carrier base frame units (9) for loading sample carriers (3) are stacked into a tower structure, each carrier base frame unit (9) is provided with a base portion, a central hole (11) is provided in the center of the base portion, the base portion extends centrally symmetrically in a radial outward direction from the central hole (11) to form a plurality of fins, each fin is formed by means of connection and enclosure of an outer peripheral side surface of the central hole (11) and an inner side surface of a side ridge extending radially from the fin, a loading slot (15) for loading the sample carrier (3) is provided on the outer peripheral surface of each fin, and a plurality of stations for placement of sample sections are provided on each sample carrier (3). The problems of an excessively large volume of the sample carrier storage rack and a small number of samples loaded per loading cycle of an automatic sample loading device under the condition of the same number of samples are solved, the space volume of the sample carrier storage rack is reduced while the throughput is increased, and the sample carrier storage rack has the characteristics of flexible operation and cost saving, and is suitable for popularization and application.

Description

A sample plate storage rack for continuous section transmission electron microscopy imaging Technical Field

[0001] This invention discloses a sample carrier storage rack for continuous slice transmission electron microscopy imaging. Background Technology

[0002] To improve the throughput of transmission electron microscopy (TEM), an automated sample loading device was added to the outside of the microscope tube. This automated sample loading device includes a robotic arm system, a sample chamber, and a vacuum system. The robotic arm system grips one sample at a time within the vacuum chamber for observation, reducing the need for vacuum-breaking during sample loading and significantly increasing the imaging throughput of TEM. In existing technical solutions, the robotic arm system integrates a sample loading / unloading system and a sample platform system. During sample loading, the robotic arm grips a sample in the sample chamber, and then the robotic arm holding the sample extends from the automated sample loading device into the TEM tube to observe the sample. During sample unloading, the robotic arm retracts from the TEM tube, placing the sample back into the sample chamber. However, this method only allows for viewing one sample at a time, leaving room for further throughput improvement.

[0003] In the prior art, CN206976282U discloses a scanning electron microscope sample stage suitable for semi-cylindrical samples, including a base. A baffle is vertically fixed on the upper surface of the base. Several transverse through slots are evenly distributed along the longitudinal direction on the bottom of the baffle. A transversely extending slide plate is inserted into each of the transverse through slots. A protrusion is vertically fixed at both ends of each slide plate. A spring is connected between the protrusion at one end of each slide plate and the baffle. The springs of several slide plates are all located on the same side, allowing multiple samples to be placed at once. The extension and retraction of each slide plate are independent, resulting in high efficiency and strong adaptability. Although this prior art can place multiple samples at once, the sample stage is relatively large and cannot flexibly adjust the number of samples according to actual needs.

[0004] CN220894188U discloses a scanning electron microscope (SEM) sample stage suitable for semi-cylindrical samples, including a base plate with a mounting assembly on top. The mounting assembly includes a support plate disposed on the base plate, a rotating motor at the center of the top of the support plate, a rotating ring rotatably connected to the top of the support plate, and a fixedly connected positioning ring inside the rotating ring on the top of the support plate. The outer wall of the positioning ring abuts against and is rotatably connected to the inner wall of the rotating ring. This prior art uses a rotating motor and a drive motor to drive a placement tray to move horizontally and rotate. In later use, after placing multiple samples on the placement tray at once, samples at different positions on the placement tray can be easily moved to the observation position of the SEM. However, this sample stage has a complex structure, high cost, and also suffers from a large size.

[0005] Based on the problems existing in the prior art, the purpose of this invention is to provide a sample plate storage rack that can increase throughput while reducing the space volume of the sample plate storage rack, and is flexible in operation and cost-effective. Technical solutions

[0006] Based on the above objectives, the present invention first provides a sample plate storage rack for transmission electron microscopy imaging. The storage rack is a tower structure composed of plate base frame units for loading sample plates stacked together. Each plate base frame unit is provided with a base, and a central hole is provided in the center of the base. N fins extend symmetrically from the base in a radially outward direction from the central hole. Each fin is provided with a loading groove for loading sample plates, which is surrounded by the inner surface of the inner circumference and the inner surfaces of two radially extending side ridges, and the outer circumference is open. A sample strip station for placing sample strips is provided on the sample plate.

[0007] In this invention, N is a positive integer. For example, the base extends 2, 3, 5, 6, or 8 winglets in a radially outward direction from the central hole. In a specific embodiment of this invention, there are 4 winglets.

[0008] In a preferred embodiment, the sample carrier plate is a rectangular structure. In a more preferred embodiment, the sample carrier plate is a rectangular structure, and the radial length of the sample carrier plate is longer than the radial extension length of the loading groove.

[0009] In another preferred embodiment, the sample carrier plate is provided with 1-50 sample strip stations. The sample strips can be arranged in a matrix of multiple stations, such as 1×5, 2×5, 3×5, 4×5, 5×6, 5×8, etc. Those skilled in the art can adopt a suitable matrix design according to actual needs and the technical parameters of the automatic sample loading device for electron microscopes. In a specific embodiment of the present invention, the sample strips are designed as 2×5 multiple stations. Two sample strips are attached to the sample carrier plate, each sample strip containing 5 ultrathin section samples, and each sample position corresponds one-to-one with the well position of the sample carrier plate.

[0010] In a preferred embodiment, the sample carrier plate is provided with robotic arm gripper slots on both sides extending radially beyond the loading groove. The design that the radial length of the sample carrier plate is longer than the radial extension length of the loading groove is to facilitate robotic arm gripping. In a specific embodiment of the invention, the robotic arm gripper slots are designed to be arc-shaped.

[0011] The carrier plate frame unit of the present invention is configured as a hollow structure with four winglets extending radially symmetrically from the central hole. In a preferred embodiment, the four winglets extend radially in a cross-symmetric manner from the central hole, that is, each winglet has a 90-degree angle with the adjacent winglet, and the four winglets are evenly distributed around the circumference of the central hole.

[0012] In a more preferred embodiment, a first cuboid-shaped limiting boss is provided at the top of the area adjacent to the loading slot on the outer edge of the central hole of each carrier base unit. The first limiting boss can be provided in two corresponding areas adjacent to the four loading slots on the outer edge of the central hole of each carrier base unit. A second annular-shaped limiting boss is provided at the top of the inner edge of the central hole of each carrier base unit. The bottom of the inner edge of the central hole is stepped. A limiting groove that mates with the first limiting boss is provided at the bottom of each loading slot extending radially along the central hole of each carrier base unit. Four limiting grooves arranged in a cross shape are provided along the four flanges at the bottom of each carrier base unit. The first limiting boss mates with the limiting grooves of the carrier base units stacked on top of it, and the second limiting boss mates with the bottom of the central hole of the carrier base units stacked on top of it, thus performing a limiting function. Through these limiting mechanisms, the carrier base units can be stacked into a multi-layered tower structure, with each layer having four loading slots, and each loading slot holding one sample carrier plate. In one specific embodiment of the present invention, the tower structure has 13 layers, and each sample carrier plate has a 2×5 multi-station design. In this scheme, the sample carrier plate storage rack can store 2×5×4×13=520 workstations.

[0013] In a preferred embodiment, a spring is circumferentially disposed on the loading slot of the carrier plate base unit. The spring is fixed to the radially extending top positions on both sides of the loading slot. A ball-shaped positioning screw is disposed on the radially extending inner side of the loading slot. The spring is used to make the sample carrier plate flush with the bottom surface of the loading slot, and the ball-shaped positioning screw is used to make the sample carrier plate flush with the side surface of the loading slot. In a specific embodiment, the spring is fixed to the radially extending top positions on both sides of the loading slot by screws, and the ball-shaped positioning screw is threaded into the side surface of the loading slot of the carrier plate base unit, preferably located on one side.

[0014] In a preferred embodiment, the sample carrier plate has steps on both sides of its bottom surface, the height of which makes the total height of the sample carrier plate greater than the thickness of the sample strip. The steps serve to protect the sample strip from being scraped by the loading groove during the loading process.

[0015] Secondly, the present invention provides an apparatus for automated sample loading in transmission electron microscopy, the apparatus comprising a robotic arm system, a sample chamber and a vacuum system, and a sample carrier storage rack containing the aforementioned sample carrier plate.

[0016] Finally, the present invention provides a method for automatically loading samples using the aforementioned sample carrier storage rack, the method comprising the following steps:

[0017] 1. Insert the sample carrier plate with the sample strip placed into the loading slot of the carrier plate base unit in the specified order and direction.

[0018] 2. Place the sample carrier storage rack containing the sample carrier plate in the designated position of the automatic sample loading device. The Z-axis robotic arm in the vacuum chamber of the automatic sample loading device moves down to grip the robotic arm gripper groove on the top side of the sample carrier storage rack, causing the entire sample carrier storage rack to move. The Z-axis robotic arm then returns the sample carrier storage rack to its original position.

[0019] 3. The automatic sample loading device combines the extension and gripping motion of the X-axis robotic arm and the lifting and rotating motion of the Z-axis robotic arm within the vacuum chamber to achieve sample loading and unloading operations for the transmission electron microscope. Beneficial effects

[0020] The technical solution of this invention uses a tower-type cross-symmetrical structure design, which greatly reduces the space volume of the sample carrier storage rack. The symmetrical design ensures that each layer of the sample storage rack has the same structure, saving costs while allowing for flexible adjustment of the sample carrier storage capacity.

[0021] This invention employs a multi-station sample carrier plate, allowing 10 or more samples to be delivered into the transmission electron cavity at once using a single sample carrier plate. Compared with existing technologies, the throughput is increased by 10 times or more. It solves the problem of excessively large sample storage rack volume for the same number of samples, and the use of a multi-station sample carrier plate addresses the issue of limited sample loading capacity in automated sample loading devices.

[0022] The positioning design of the sample carrier base frame storage slot in this invention enables the multi-station sample carrier to fit snugly with the sample storage rack slot, achieving precise positioning of the multi-station sample carrier.

[0023] In summary, the technical solution of the present invention has the characteristics of compact structure, flexible operation, cost saving, increased throughput and precise positioning, and is suitable for widespread application. Attached Figure Description

[0024] Figure 1 is a schematic diagram of the multi-station sample carrier plate structure, where Figure 1A is the front view, Figure 1B is the bottom view, and Figure 1C is the axial view.

[0025] Figure 2 is a schematic diagram of the sample carrier storage rack structure, where Figure 2A is the front view, Figure 2B is the top view, and Figure 2C is the axial view.

[0026] Figure 3 is a schematic diagram of the structure of a single-layer sample carrier base frame storage slot, where Figure 3A is a bottom view and Figure 3B is an axial view.

[0027] Figure 4 is a schematic diagram of the automatic sample loading device's robotic arm gripping the sample carrier plate storage rack for loading and unloading.

[0028] In the diagram: 1-Sample tray station, 2-Robot arm gripper groove, 3-Sample carrier plate, 4-Step, 5-Sample carrier plate base frame fixing screw, 6-Spring fixing screw, 7-Spring, 8-Ball positioning set screw, 9-Carrier plate base frame unit, 10-Limiting groove, 11-Center hole, 12-Second limiting boss, 13-Spring mounting screw hole, 14-First limiting boss, 15-Loading groove, 16-Ball positioning set screw mounting screw hole. The best embodiment of the present invention

[0029] The present invention will be further described below with reference to specific embodiments, and the advantages and features of the present invention will become clearer as a result of the description. However, these embodiments are merely exemplary and do not constitute any limitation on the scope of protection defined by the claims of the present invention.

[0030] Referring to the accompanying drawings of the present invention, as shown in Figures 1 to 3, in a specific embodiment of a sample plate storage rack for continuous section transmission electron microscopy imaging provided by the present invention, the storage rack consists of a tower-like structure formed by stacking plate base frame units 9 for loading sample plates 3. Each plate base frame unit 9 has a central hole 11, and four winglets extend radially symmetrically from the central hole. Each winglet has a loading groove 15 for loading the sample plate 3, enclosed by an inner circumferential surface and two radially extending inner surfaces, with an open outer circumferential surface. The radial length of the sample plate is longer than the radial extension length of the loading groove to facilitate the gripping of the sample plate by a robotic arm. A sample strip station 1 for placing sample strips is provided on the sample plate 3. The plate base frame units 9 are fixed together by sample plate base frame fixing screws 5.

[0031] In a preferred embodiment, the sample carrier plate 3 has a rectangular structure, and the radial length of the sample carrier plate is longer than the radial extension length of the loading groove. In a more preferred embodiment, the sample carrier plate 3 has a rectangular structure. The present invention designs the radial length of the sample carrier plate to be longer than the radial extension length of the loading groove, aiming to facilitate the robotic arm gripper to stably grasp the sample carrier plate during operation.

[0032] In another preferred embodiment, the sample carrier plate 3 is provided with 1-50 sample strip stations 1. The sample strips can be arranged in a matrix of multiple stations, such as 1×5, 2×5, 3×5, 4×5, 5×6, 5×8, etc. Those skilled in the art can adopt a suitable matrix design according to actual needs and the technical parameters of the automatic sample loading device for electron microscopes. In a specific embodiment of the present invention, the sample strips are designed as 2×5 multiple stations. Two sample strips are attached to the sample carrier plate 3, each sample strip containing 5 ultrathin section samples, and each sample position corresponds one-to-one with the well position of the sample carrier plate.

[0033] In a preferred embodiment, the sample carrier plate 3 is provided with robotic arm gripper grooves 2 on both sides that extend radially beyond the loading groove. In a specific embodiment of the invention, the robotic arm gripper grooves 2 are designed to be arc-shaped.

[0034] The carrier plate base unit 9 of the present invention is configured as a hollow structure, with four winglets extending radially symmetrically from the central hole. In a preferred embodiment, the four winglets extend radially in a cross-symmetric manner from the central hole, that is, each winglet has a 90-degree angle with the adjacent winglet, and the four winglets are evenly distributed around the circumference of the central hole.

[0035] In a more preferred embodiment, a first limiting boss 14 with a cuboid structure is provided on the top of the area adjacent to the loading slot 15 at the outer edge of the base of the carrier frame unit 9. The first limiting boss 14 can be provided in two corresponding areas adjacent to the four loading slots at the outer edge of the base of each carrier frame unit. A second limiting boss 12 with a circular structure is provided on the top of the inner edge of the central hole of the carrier frame unit. The bottom of the inner edge of the central hole is stepped. A limiting slot 10 that mates with the first limiting boss 14 is provided at the bottom of each loading slot extending radially along the central hole of the carrier frame unit. A total of four limiting slots 10 arranged in a cross shape are provided on the bottom of the four wings of each carrier frame unit. The first limiting boss 14 mates with the limiting slots 10 of the carrier frame units stacked thereon, and the second limiting boss 12 mates with the bottom of the central hole of the carrier frame units stacked thereon, thus performing a limiting function. The point-like limiting of the first limiting boss 14 and the limiting groove 10, and the circumferential limiting of the second limiting boss 12 and the central hole, provide a more stable limiting mechanism. The carrier plate base unit can be stacked into a multi-layered tower structure, with each layer having four loading slots, each slot holding one sample carrier plate. In one specific embodiment of the invention, the tower structure has 13 layers, and each sample carrier plate has a 2×5 multi-station design. In this scheme, the sample carrier plate storage rack can store 2×5×4×13=520 workstations.

[0036] In a preferred embodiment, a spring 7 is circumferentially arranged on the loading slot of the carrier plate base unit 9. The spring 7 is fixed to the radially extending top positions on both sides of the loading slot. A ball-bead positioning screw 8 is provided on the radially extending inner side of the loading slot. The spring 7 is used to make the sample carrier plate flush with the bottom surface of the loading slot, and the ball-bead positioning screw 8 is used to make the sample carrier plate flush with the side of the loading slot. In a specific embodiment, the spring 7 is fixed to the radially extending top positions on both sides of the loading slot by spring screws 6 passing through spring screw mounting holes 13. The ball-bead positioning screw 8 is threaded into the side of the loading slot 15 of the carrier plate base unit through ball-bead positioning screw mounting holes 16, preferably located on one side.

[0037] In a preferred embodiment, steps 4 are provided on both sides of the bottom surface of the sample carrier plate, the height of which makes the total height of the sample carrier plate greater than the thickness of the sample strip. The steps 4 are used to protect the sample strip from being scraped by the loading groove during the loading of the sample carrier plate.

[0038] Figure 4 shows the apparatus for automated sample loading in transmission electron microscopy provided by the present invention. The apparatus includes a robotic arm system, a sample chamber and a vacuum system, as well as a sample carrier storage rack containing the aforementioned sample carrier. The specific steps are as follows:

[0039] 1. Insert the sample carrier plate 3 with the sample tape attached into the loading slot of the carrier plate base unit 9 in the specified order and direction.

[0040] 2. Place the sample carrier storage rack containing the sample carrier plate 3 at the designated position of the automatic sample loading device. The Z-axis robotic arm in the vacuum chamber of the automatic sample loading device moves down to grip the robotic arm gripper groove 2 on the top side of the sample carrier storage rack, causing the entire sample carrier storage rack to move. The Z-axis robotic arm then returns the sample carrier storage rack to its original position.

[0041] 3. The specific actions of sample loading are as follows: After the Z-axis robotic arm carries the sample carrier storage rack to the sample loading position, the X-axis robotic arm picks up the target sample carrier. The Z-axis robotic arm carries the sample carrier storage rack back to the Standby position. The X-axis robotic arm delivers the sample to the transmission electron microscope sample chamber and then returns to the Standby position.

[0042] 4. The specific actions for sample loading are as follows: the X-axis robotic arm extends into the sample chamber of the transmission electron microscope to pick up the sample carrier plate 3, the X-axis robotic arm returns the sample carrier plate 3 to the Standby position, the Z-axis robotic arm lowers the sample storage rack to the loading / unloading position, the X-axis robotic arm puts the sample carrier plate back to the designated position, and both the X-axis robotic arm and the Z-axis robotic arm return to their respective Standby positions.

[0043] 5. The automatic sample loading device combines the extension and gripping motion of the X-axis robotic arm and the lifting and rotating motion of the Z-axis robotic arm within the vacuum chamber to achieve sample loading and unloading operations for the transmission electron microscope.

[0044] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0045] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of the invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the invention should be included within the protection scope of the invention. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. A sample carrier storage rack for electron microscope imaging, characterized in that, The sample carrier storage rack is a tower structure formed by stacking carrier base units for loading sample carriers. Each carrier base unit has a base with a central hole in the center. N winglets extend symmetrically from the base in a radially outward direction from the central hole. Each winglet has a loading groove for loading sample carriers, which is surrounded by the outer peripheral side of the central hole and the inner side of the radially extending side ridge of the winglet, and has an open outer peripheral surface. A sample strip station for placing sample strips is provided on the sample carrier.

2. The sample carrier storage rack according to claim 1, characterized in that, The sample carrier plate has a rectangular structure, and the radial length of the sample carrier plate is longer than the radial extension length of the loading groove.

3. The sample carrier storage rack according to claim 1, characterized in that, The sample carrier plate is equipped with 1-50 sample strip stations.

4. The sample carrier storage rack according to claim 3, characterized in that, The sample carrier plate is provided with robotic arm gripper slots on both sides that extend radially beyond the loading groove.

5. The sample carrier storage rack according to claim 1, characterized in that, N=4, and the four blades extend radially in a cross-shaped symmetrical manner from the central hole.

6. The sample carrier storage rack according to claim 5, characterized in that, A first limiting boss with a cuboid structure is provided at the top of the area adjacent to the loading slot on the outer edge of the base of the carrier plate base unit. A second limiting boss with a circular ring structure is provided at the top of the inner edge of the central hole of the carrier plate base unit. The bottom of the inner edge of the central hole is stepped. A limiting groove that mates with the first limiting boss is provided at the bottom of each loading slot that extends radially along the central hole of the carrier plate base unit. The first limiting boss mates with the limiting groove of the carrier plate base unit stacked thereon, and the second limiting boss mates with the bottom of the central hole of the carrier plate base unit stacked thereon, thereby performing a limiting function.

7. The sample carrier storage rack according to claim 1, characterized in that, A spring is provided circumferentially on the loading slot of the carrier plate base unit. The spring is fixed to the top of the radially extending sides of the loading slot. A ball positioning screw is provided on the radially extending inner side of the loading slot. The spring is used to make the sample carrier plate flat with the bottom surface of the loading slot. The ball positioning screw is used to make the sample carrier plate flat with the side of the loading slot.

8. The sample carrier storage rack according to claim 1, characterized in that, The sample carrier plate has steps on both sides of its bottom surface, and the height of the steps makes the total height of the sample carrier plate greater than the thickness of the sample strip.

9. A device for automated sample loading in a transmission electron microscope, characterized in that, The device includes a robotic arm system, a sample chamber and a vacuum system, and a sample carrier storage rack containing any one of claims 1-8.

10. A method for automatically loading samples using a sample carrier storage rack according to any one of claims 1-8, characterized in that, The method includes the following steps: (1) Insert the sample carrier plate with the sample strip placed in it into the loading slot of the carrier plate base unit in the specified order and direction; (2) Place the sample carrier storage rack containing the sample carrier in the designated position of the automatic sample loading device. The Z-axis robotic arm in the vacuum chamber of the automatic sample loading device moves down to grip the robotic arm gripper groove on the top side of the sample carrier storage rack, causing the entire sample carrier storage rack to move. The Z-axis robotic arm then clamps the sample carrier storage rack back to its original position. (3) The extension and gripping motion of the X-axis robotic arm and the lifting and rotating motion of the Z-axis robotic arm in the vacuum chamber of the automatic sample loading device are combined in an orderly manner to realize the sample loading and unloading work of the transmission electron microscope.

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