A vacuum protection system for a direct detection imaging refrigeration camera

Abstract

The application discloses a vacuum protection system of a direct detection imaging refrigeration camera, which comprises a vacuum cavity for providing a vacuum space, a camera positioning structure in the vacuum cavity for providing a fixing function for the refrigeration camera, a refrigeration camera station on the camera positioning structure for placing the refrigeration camera, a refrigeration camera top sealing plate arranged on the upper portion of the refrigeration camera station, a grabbing mechanism for grabbing the refrigeration camera top sealing plate, a screw machine for tightening the refrigeration camera top sealing plate screw with a fixed torque, a vacuum pump for forming the vacuum space, a vacuum gauge for measuring the air pressure of the vacuum cavity, and a circuit interface and a vacuum interface arranged on the outer plate of the vacuum cavity respectively. In the application, the camera is placed in the vacuum cavity, and the refrigeration camera can be automatically sealed after vacuumizing, so that an independent vacuum is formed in the refrigeration camera cavity, other interfaces do not need to be reserved, the leaking surface is reduced, the camera occupying space is reduced, and the overall cost is reduced.

Description

Technical Field

[0001] This invention discloses a vacuum protection system for a cryo-electron microscopy camera, belonging to the field of cryo-electron microscopy technology. Background Technology

[0002] Cryo-electron microscopy has become an indispensable core technology in the field of structural biology. The direct-probe imaging cooled camera, as the "eye" of the cryo-electron microscope, determines its ability to "see clearly." Direct-probe imaging cooled cameras require vacuum protection during transportation and operation to prevent dust and water vapor from contaminating the imaging chip. Existing vacuum protection solutions are costly, requiring pre-installed evacuation ports on the camera and the installation of additional vacuum valves or quick-connect fittings, or pre-installed copper tubing that is cut and welded for sealing after vacuuming. Regardless of the solution, multiple additional interfaces are needed, increasing the overall camera space. The sealing effect is also relatively poor, maintaining only a low vacuum level. The additional interfaces also increase the risk of leakage, providing weak protection for the camera's imaging chip. Furthermore, the vacuum condition inside existing cameras is difficult to assess, and the situation remains unclear after installation.

[0003] The purpose of this invention is to provide a vacuum protection system for a cooling camera that overcomes the above-mentioned technical defects, has a good sealing effect, sufficient vacuum volume, and is easy to operate. Summary of the Invention

[0004] Based on the above objectives, the present invention first provides a vacuum protection system for cryo-electron microscopy. The vacuum protection system includes a vacuum chamber providing a vacuum space, a camera positioning mechanism located within the vacuum chamber for fixing a cryogenic camera, a cryogenic camera station located on the camera positioning mechanism for placing the cryogenic camera, a cryogenic camera top sealing plate with vacuum detection function provided above the cryogenic camera station, a gripper for gripping the cryogenic camera top sealing plate and connecting the internal cavity of the camera with the vacuum chamber in a through or closed state, a lead screw motor for driving the gripper to move up and down, a motor fixing plate located above a constant torque screw machine for fixing the motor, a constant torque screw machine for tightening the screws of the camera top sealing plate with a constant torque, and a screw machine fixing plate for fixing the constant torque screw machine. The outer plate of the vacuum chamber is also provided with a circuit interface and a vacuum interface.

[0005] In a preferred embodiment, the bottom of the top cover plate of the cooled camera is provided with a placement slot for placing the vacuum degree detection function unit inside the camera. Screw fixing holes are reserved on its surface. The screw fixing holes match the holes of the cooled camera and the transmission electron microscope, making it compatible with different models of electron microscopes and corresponding cooled cameras.

[0006] In a preferred embodiment, the top of the cooling camera's top cover plate is provided with a gripping slot for easy gripping by a hand.

[0007] In a preferred embodiment, a through slot is provided in the motor mounting plate, allowing the gripper to grip the top sealing plate of the cooling camera and move it up and down to achieve communication or closure between the vacuum chamber of the cooling camera and the vacuum system chamber. When the gripper grips the top sealing plate of the cooling camera and presses the camera down, the camera forms an independent vacuum state. When the gripper grips the sealing plate and moves it up, the independent vacuum of the camera is opened, thereby communicating with the vacuum chamber of the system.

[0008] In a more preferred embodiment, the opening of the cooled camera is equipped with a sealing ring, which is compressed when the gripper grabs the top sealing plate of the cooled camera and presses the camera down to enhance the sealing effect.

[0009] In a preferred embodiment, a movable plate is provided between the screw fixing plate and the top sealing plate of the cooling camera. The lead screw motor is connected to the movable plate and drives the movable plate to move up and down. A hole for a gripper to pass through is provided in the middle of the movable plate. The gripper is fixed to the movable plate and moves up and down with the movable plate, thereby driving the top sealing plate of the cooling camera to rise or fall.

[0010] In a preferred embodiment, the screw machine is fixed to a movable plate and moves up and down with the movable plate. The movable plate has holes at its four corners for screws to pass through. The movable plate enables the constant torque screw machine to move up and down for tightening the screws on the top sealing plate of the camera with a constant torque.

[0011] In a preferred embodiment, the base plate of the camera positioning mechanism is provided with a locking positioning mechanism that matches the camera. The locking positioning mechanism is a detachable structure and is compatible with different models of cooling cameras.

[0012] In a preferred embodiment, the base plate of the camera positioning mechanism is provided with a locking positioning mechanism that matches the camera. The locking positioning mechanism is a detachable structure and is compatible with different models of cooling cameras.

[0013] Secondly, the present invention also provides a method for generating a vacuum space using the above-mentioned vacuum protection system, the method comprising the following steps: S1: Place the cooled camera inside the vacuum protection system; S2: Turn on the lead screw motor switch. The lead screw motor lifts the top sealing plate of the cooling camera, opening the independent internal cavity of the cooling camera and connecting it with the cavity of the vacuum system. S3: Start the mechanical pump and molecular pump switch, use pump force to remove air and generate negative pressure, use a vacuum gauge to detect the air pressure in the vacuum system cavity until the target vacuum level is reached; S4: The specified lead screw motor moves the top sealing plate of the cooling camera downward, separating the internal space of the camera from the vacuum chamber and compressing the camera sealing ring. After the screw is tightened by the fixed torque screw machine, the vacuum degree inside the camera is evaluated by the camera internal vacuum degree detection function unit. S5: Remove the camera that meets the vacuum requirements from the vacuum system.

[0014] Based on considerations of reducing costs, minimizing camera size, and increasing the vacuum level inside the camera, this invention provides a vacuum protection system for a direct-detection imaging cooled camera. The vacuum protection system of this invention demonstrates the following superior technical effects in addressing the technical problems of existing technologies: The vacuum protection system of this invention places the camera inside a vacuum chamber. After evacuation, it automatically seals and cools the camera in a vacuum environment, creating an independent vacuum within the camera chamber. This eliminates the need for other interfaces, reducing leakage points and providing better vacuum protection for the direct-detection imaging cooled camera. It also reduces the space occupied by the camera, making lead shielding simpler and more efficient, lowering the overall cost of the camera, and facilitating the design and installation of subsequent lead shielding (transmission electron microscopes generate radiation during use, requiring lead shielding to cover the entire camera). The camera top sealing plate provided by this invention has a vacuum detection function, allowing for real-time monitoring of the vacuum level inside the camera. Furthermore, the camera top sealing plate is recyclable and reusable after camera installation. Attached Figure Description

[0015] Figure 1 This is a perspective view of an overall vacuum protection system according to an embodiment of the present invention; Figure 2 A perspective view of the vacuum protection system and its associated support device of the present invention is shown; Figure 3 The top cover of the direct detection imaging cooled camera and its accessories are shown; Figure 4 The connection mechanism between the top cover and the gripper of the direct-probe imaging cooled camera is shown; Figure 5 A stereoscopic view of the top cover of the direct-probe imaging cooled camera is shown.

[0016] The reference numerals in the figure are as follows: 001-Vacuum gauge; 002-Ultra-high vacuum adapter chamber; 003-Molecular pump; 004-Mechanical pump; 005-Vacuum system controller; 100 - Vacuum chamber; 200 - Camera top sealing plate fixing mechanism; 300 - Camera top sealing plate; 400 - Direct detection imaging cooled camera; 101-Vacuum interface of vacuum chamber; 102-Circuit interface of vacuum chamber; 103-Camera positioning bottom of vacuum chamber; 201-Gripper; 202-Torque screwdriver; 203-Screw motor; 204-Motor mounting plate; 205-Screwdriver mounting plate; 206-Moving plate; 207-Gripper mounting plate; 208-Grip slot; 209-Cable interface; 210-Placement slot. Detailed Implementation

[0017] 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.

[0018] Figure 1 A specific embodiment of the present invention is provided, wherein the vacuum protection system includes: a vacuum chamber 100, a cooling camera 400 located inside the vacuum chamber 100, a camera positioning structure 103 located at the bottom of the cooling camera 400 to provide support thereto, a camera top sealing plate 300 located at the top of the cooling camera 400 to provide vacuum protection for the cooling camera 400, a constant torque screwdriver 202 located on the upper part of the camera top sealing plate 300, a gripper 201 for lifting and lowering the camera top sealing plate 300 to complete the connection between the internal cavity of the camera and the vacuum chamber and to maintain the vacuum inside the camera, and a camera top sealing plate fixing mechanism 200 for fixing the camera top sealing plate 300 to the top of the vacuum chamber 100.

[0019] Figure 1 The circuit interface 102 located at the top of the vacuum chamber 100 and the vacuum interface 101 on one side for creating a vacuum environment are also provided.

[0020] Figure 2 A perspective view of the vacuum protection system and its associated support device of the present invention is shown, which includes a vacuum gauge 001 for measuring the gas pressure of the entire vacuum protection system, as well as an ultra-high vacuum transfer chamber 002, a molecular pump 003, a mechanical pump 004, and a vacuum system controller 005.

[0021] Figure 3 The top cover fixing mechanism and its supporting devices for a direct-detection imaging cooled camera are shown. The bottom of the gripper 201 is fixed to the top cover 300 of the camera via a gripper fixing plate 207, the structure of which matches the gripping slot 208 of the top cover 300. When the gripper 201 clamps, the gripper fixing plate 207 extends into the slot 208 of the top cover (see...). Figure 4 While gripper 201 clamps the top cover plate 300 of the camera, gripper fixing plate 207 can also hold the top cover plate 300 of the camera in place, making it more secure and preventing it from falling accidentally.

[0022] Figure 3 In the middle, between the motor fixing plate 204 and the camera top sealing plate 300, from top to bottom, there are screw plate fixing plate 205 and movable plate 206 through which the gripper 201 passes. The motor fixing plate 204, screw plate fixing plate 205, movable plate 206 and camera top sealing plate 300 are all rectangular in shape with corresponding vertical orientation. Four constant torque screw machines are set at the four corners of the screw plate fixing plate 205 for tightening the screws of the camera top sealing plate 300 with constant torque. The bottom of the screw machine has a screw head limiting structure with magnetism for limiting and fixing the screws. The screws are fixed by rotating the motor of the screw machine.

[0023] The lead screw motor 203 is fixed to the motor mounting plate 204, and the lead screw nut and gripper 201 are fixed to the movable plate 206. That is, the rotation of the lead screw motor drives the lead screw nut to move up and down. Since the lead screw nut is fixed to the movable plate, the motor drives the movable plate 206 to move up and down. Simultaneously, the gripper 201, fixed to the movable plate, also moves up and down. The motor mounting plate 204 is fixed to the top of the vacuum chamber 100 and provides electrical connection to the motor 203 through its open circuit interface 102.

[0024] Figure 4 A more detailed connection relationship is given for the gripper 201, the gripper fixing plate 207, and the camera top cover 300. The gripper fixing plate 207 is fixed to the bottom of the gripper 201, and its structure matches the gripping slot 208 on the camera top cover 300. When the gripper 201 clamps, the gripper fixing plate 207 extends into the gripping slot 208 of the camera top cover. While the gripper 201 clamps the camera top cover 300, the gripper fixing plate 207 can also secure the camera top cover 300, making it more reliable and preventing it from falling accidentally.

[0025] Figure 5 The top cover plate 300 of the camera shows the pre-welded cable interface 209 at the bottom, which has a slot 210 inside for placing a vacuum detection device, so that the vacuum status inside the camera can still be detected and read after the camera is removed from the vacuum system.

[0026] Through a unique design, the vacuum chamber provided by this invention is an internally sealed space that can withstand the atmospheric pressure generated by a high vacuum. This chamber can achieve a 5×10 -5 A vacuum level of Pa provides better vacuum protection for the camera.

Claims

1. A vacuum protection system for a direct detection imaging refrigeration camera, comprising: The vacuum protection system includes a vacuum chamber providing a vacuum space, a camera positioning mechanism located within the vacuum chamber providing a fixed position for the cooling camera, a cooling camera station located on the camera positioning mechanism for placing the cooling camera, a cooling camera top sealing plate with vacuum detection function provided above the cooling camera station, a gripper for gripping the cooling camera top sealing plate and connecting the internal cavity of the camera with the vacuum chamber in a through or closed state, a lead screw motor for driving the gripper to move up and down, a motor fixing plate located above the constant torque screw machine for fixing the motor, a constant torque screw machine for tightening the screws of the camera top sealing plate with a constant torque, and a screw machine fixing plate for fixing the constant torque screw machine. An electrical interface and a vacuum interface are also respectively provided on the outer plate of the vacuum chamber.

2. The vacuum protection system for a direct detection imaging refrigerator camera of claim 1, wherein, The top cover plate of the cooled camera has a slot at the bottom for placing the vacuum detection function unit inside the cooled camera. Screw fixing holes are reserved on its surface. The screw fixing holes match the holes of the cooled camera and the transmission electron microscope, making it compatible with different models of electron microscopes and corresponding cooled cameras.

3. The vacuum protection system for a direct-detection imaging cooled camera according to claim 1, characterized in that, The top of the cooling camera's top cover plate is provided with a gripping slot for easy gripping by a hand.

4. The vacuum protection system for a direct-detection imaging cooled camera according to claim 1, characterized in that, The motor mounting plate has a through slot, which allows the gripper to grasp the top sealing plate of the cooling camera and move it up and down to achieve the connection or closure of the vacuum chamber of the cooling camera and the vacuum system. When the gripper grasps the top sealing plate of the cooling camera and presses it down to tighten the cooling camera, the cooling camera forms an independent vacuum state. When the gripper grasps the sealing plate and moves it up, the independent vacuum of the cooling camera is opened, thereby connecting with the vacuum chamber of the system.

5. The vacuum protection system for a direct-detection imaging cooled camera according to claim 4, characterized in that, The opening of the cooling camera is equipped with a sealing ring. When the gripper grabs the top sealing plate of the cooling camera and presses the camera down, the sealing ring is compressed to enhance the sealing effect.

6. The vacuum protection system for a direct-detection imaging cooled camera according to claim 1, characterized in that, A movable plate is provided between the screw machine fixing plate and the top sealing plate of the cooling camera. The lead screw motor is connected to the movable plate and drives the movable plate to move up and down. A hole is provided in the middle of the movable plate for a gripper to pass through. The gripper is fixed to the movable plate and moves up and down with the movable plate, thereby driving the top sealing plate of the cooling camera to rise or fall.

7. The vacuum protection system for a direct-detection imaging cooled camera according to claim 6, characterized in that, The screwdriver is fixed to the movable plate and moves up and down with the movable plate. The movable plate has holes at its four corners for screws to pass through. The movable plate enables the constant torque screwdriver to move up and down, and is used to tighten the screws on the top sealing plate of the camera with a constant torque.

8. The vacuum protection system for a direct-detection imaging cooled camera according to claim 1, characterized in that, The base plate of the camera positioning mechanism is equipped with a positioning mechanism that matches the camera. The positioning mechanism is a detachable structure and is compatible with different models of cooling cameras.

9. The vacuum protection system for a direct-detection imaging cooled camera according to claim 1, characterized in that, The vacuum chamber is externally equipped with a mechanical pump, an ultra-high vacuum transfer chamber, and a molecular pump connected to the vacuum interface.

10. A method for creating a vacuum space in a cooled camera using the vacuum protection system of any one of claims 1-9, characterized in that, The method includes the following steps: S1: Place the cooled camera inside the vacuum protection system; S2: Turn on the lead screw motor switch. The lead screw motor lifts the top sealing plate of the cooling camera, opening the independent internal cavity of the cooling camera and connecting it with the cavity of the vacuum system. S3: Start the mechanical pump and molecular pump switch, use pump force to remove air and generate negative pressure, use a vacuum gauge to detect the air pressure in the vacuum system cavity until the target vacuum level is reached; S4: The specified lead screw motor moves the top sealing plate of the cooling camera downward, separating the internal space of the cooling camera from the vacuum chamber and compressing the camera sealing ring. After the screw is tightened by the fixed torque screw machine, the vacuum degree inside the camera is evaluated by the camera internal vacuum degree detection function unit. S5: Remove the cooled camera that meets the vacuum requirements from the vacuum system.

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