Sealing door
By using low-temperature resistant non-metallic plastic materials in the screw nuts and guide bearings of sealed doors, combined with heating defrost and metal shield design, the problem of sealed doors being easily stuck in low-temperature environments is solved, and the more Smooth opening and closing and better sealing effect.
Patent Information
- Application Number
- CN202411687684.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-22
- Publication Date
- 2025-02-14
AI Technical Summary
Existing sealed doors are prone to stuttering due to frost in low temperature environments, making it difficult to open and close.
Screw nuts are made of non-metallic plastic to reduce the possibility of frost and set up heating parts near the guide grooves to defrost, while adding metal shields outside key moving parts to reduce the impact of frost.
It effectively reduces the risk of frosting and stuck in movable parts in low-temperature environments, reduces the resistance and wear during opening and closing, enables the door body to open and close smoothly, and improves the sealing effect.
Smart Images
Figure CN119436698A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of sealed doors, and in particular provides a sealed door. Background Art
[0002] The existing automatic sealing door of the sample library operates in a low temperature environment, for example, at a low temperature of -80℃, the automatic door switch mostly uses a motor to cooperate with a sprocket chain to achieve transmission. Because the chain has many movable joints, when the temperature difference on both sides of the automatic door is large, the sprocket chain is prone to frost and jam, causing the chain to shake more severely during transmission, the automatic door is noisy during operation, and there is a risk of causing sensor misdetection. At the same time, when the chain-driven automatic door is used horizontally, the chain is affected by gravity and the chain is suspended. The chain support needs to be limited, otherwise there is a hidden danger of misalignment and falling off. Therefore, in order to adapt to the low-temperature use environment, the automatic door switch uses a ball screw drive instead of a chain drive. Although there are fewer movable joints between the screw and the ball nut, in a low-temperature environment, the fluidity of the lubricating grease in the ball nut becomes poor, the running resistance is large, and the connection position of the screw and the ball nut is still prone to frost, causing jamming, or even unable to move.
[0003] Accordingly, the art needs a new sealed door to solve the problem that the existing sealed door is easily stuck or cannot be opened and closed in a low-temperature use environment. Summary of the invention
[0004] The present invention aims to solve the above technical problem, that is, to solve the problem that the existing sealed door is easily stuck or cannot be opened and closed in a low-temperature use environment.
[0005] In a first aspect, the present invention provides a sealing door, comprising a door bottom plate, a door body and a lead screw assembly, wherein the door bottom plate is provided with an opening, the lead screw assembly comprises a lead screw and a lead screw nut cooperating with the lead screw for movement, the lead screw nut being connected to the door body, and the lead screw being connected to the door bottom plate; wherein at least the internal thread on the lead screw nut or the entire lead screw nut is made of a first plastic material.
[0006] In the case of adopting the above technical solution, due to the large temperature difference between the inside and outside of the door body, the thermal conductivity of metal materials is stronger than that of non-metallic materials. Therefore, when there is a certain amount of water vapor in the air, the metal material can quickly conduct the surrounding heat away, so that its own temperature drops rapidly to approach the ambient temperature. For example, in the cold winter, the surface temperature of metal objects exposed to the air can reach equilibrium with the ambient temperature in a short time. Therefore, when two metal parts are in contact in a low temperature environment, it is very easy to get stuck due to frost, increase resistance, and make the door body difficult to open and close. In contrast, non-metallic plastic materials have slow thermal conductivity and the surface temperature drops relatively slowly, so they are not easy to frost. Therefore, in the case of adopting the above technical solution, the internal thread of the lead screw nut or the entire lead screw nut is set to a non-metallic plastic material, which can make it difficult to frost between the lead screw nut and the lead screw, thereby reducing the resistance and wear when opening and closing the door body, so that the door body can be opened and closed smoothly in a low temperature environment.
[0007] In the optional technical solution of the above-mentioned sealing door, the first plastic material is one or a mixture of multiple of polyethylene, polytetrafluoroethylene, polyetheretherketone, and ultra-high molecular weight polyethylene.
[0008] When the above technical solution is adopted, the material of the lead screw nut is a low-temperature resistant plastic material that can maintain stable performance in a low-temperature environment of -80°C and will not become brittle or lose strength due to temperature drop.
[0009] In the optional technical solution of the above-mentioned sealed door, guide strips are provided on both sides of the door bottom plate, guide grooves are provided on the guide strips, corresponding guide rotating parts are provided on both sides of the door body, the guide rotating parts are embedded in the guide grooves, and slide along the guide grooves when the door body is opened and closed.
[0010] When the above technical solution is adopted, the guide bearing is embedded in the guide groove. When the door body moves up and down, the guide bearing is restricted by the guide groove and moves along the guide groove, thereby ensuring the stability of the door body when moving.
[0011] In the optional technical solution of the above-mentioned sealing door, the guide groove includes a vertical section and an inclined section, the sealing door also includes a door body fixing seat and a push block, the screw nut is fixed on the push block, the door body fixing seat is fixed on the door body, the push block is provided with a guide hole, the door body fixing seat is provided with a guide column matching the guide hole, the guide column can slide in the guide hole, so that after the door body enters the inclined section from the vertical section, the door body can slide toward the direction of the door bottom plate, so that the door body is closer to the door bottom plate to enhance the sealing.
[0012] When the above technical solution is adopted, when the door body slides downward to close, the guide bearing enters the inclined section from the vertical section, and at the same time the guide column slides backward along the guide hole to move the door panel toward the door bottom plate, thereby allowing the door panel and the door bottom plate to be pressed together to ensure a sealing effect.
[0013] In an optional technical solution of the above-mentioned sealing door, a heating element is provided on the guide bar.
[0014] When the above technical solution is adopted, a groove is formed at a position of the guide bar close to the guide groove, and a heating element is arranged in the groove to heat and defrost the guide groove.
[0015] In an optional technical solution of the above-mentioned sealed door, limit universal balls are further arranged on both sides of the door body, and the limit universal balls roll along the guide strips when the door body moves.
[0016] When the above technical solution is adopted, the limiting universal ball abuts against the guide bar, and when the door is opened or closed, the ball rolls along the guide bar to limit the range of movement of the door body between the guide bars.
[0017] In an optional technical solution of the above-mentioned sealing door, a guide sleeve is arranged in the guide hole, and the guide column slides in the guide sleeve.
[0018] When the above technical solution is adopted, the sliding resistance between the guide column and the guide sleeve is reduced.
[0019] In an optional technical solution of the above-mentioned sealed door, the door body includes a door panel, door seats are arranged on both sides of the door panel, and the guide rotating member is arranged on the door seat.
[0020] When the above technical solution is adopted, the guide rotating member is fixed by the door seat to improve the installation stability and reduce interference.
[0021] In an optional technical solution of the above-mentioned sealing door, the rotating part of the guide sleeve and / or the guide rotating member is made of a second plastic material.
[0022] When the above technical solution is adopted, the rotating part of the guide bearing and the guide sleeve are set to plastic material, which can also reduce frost on the surface of the guide bearing and the guide sleeve, thereby reducing the resistance of the guide bearing during rotation and the sliding resistance of the guide column to prevent jamming.
[0023] In an optional technical solution of the above-mentioned sealed door, the screw outer cover is provided with a protective cover, and the protective cover is connected to the door bottom plate.
[0024] When the above technical solution is adopted, the protective cover can protect the lead screw and the transmission position between the lead screw and the motor. The frost of the hot and humid air first adheres to the protective cover, thereby preventing the lead screw and the transmission position between the lead screw and the motor from frosting, and reducing the impact of frost on internal moving parts.
[0025] It can be understood by those skilled in the art that the sealed door of the present invention comprises a door bottom plate, a door body and a screw assembly, the door bottom plate is provided with an opening, the screw assembly comprises a screw, a screw nut which moves in cooperation with the screw, the screw nut is connected to the door body, and the screw is connected to the door bottom plate; wherein, at least the internal thread on the screw nut or the entire screw nut is made of a first plastic material.
[0026] Due to the large temperature difference between the inside and outside of the door body, the thermal conductivity of metal materials is stronger than that of non-metallic materials. Therefore, the inventors found that when there is a certain amount of water vapor in the air, the metal material can quickly conduct the surrounding heat away, so that its own temperature drops rapidly to close to the ambient temperature, and the surface temperature of the metal object exposed to the air can reach equilibrium with the ambient temperature in a relatively short time. Therefore, when two metal parts are in contact in a low-temperature environment, it is very easy to get stuck due to frost, increase resistance, and make the door difficult to open and close. In contrast, non-metallic plastic materials have slow thermal conductivity and the surface temperature drops relatively slowly, so they are not easy to frost. Therefore, in the case of adopting the above-mentioned technical solution, the internal thread of the lead screw nut or the entire lead screw nut is set to a non-metallic plastic material, which can make it difficult to frost between the lead screw nut and the lead screw, thereby making the resistance and wear smaller when opening and closing the door body, so that the door body can be opened and closed smoothly in a low-temperature environment. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings, in which:
[0028] Figure 1 is a three-dimensional structural diagram of the sealing door of the present invention;
[0029] Figure 2 is a rear view of the sealing door of the present invention;
[0030] Figure 3 yes Figure 2 The enlarged schematic diagram of the center C;
[0031] Figure 4 yes Figure 2 Sectional view at AA in the middle;
[0032] Figure 5 yes Figure 4 Schematic diagram at D in the middle;
[0033] Figure 6 It is a schematic diagram of the door body of the present invention;
[0034] Figure 7 is a right side view of the sealing door of the present invention when it is opened;
[0035] Figure 8 yes Figure 7 Schematic diagram at E in the middle;
[0036] Fig. 9 is a right side view of the sealing door of the present invention when it is closed;
[0037] Fig.10 yes Fig. 9 Enlarged view at F in the middle;
[0038] Fig.11 is a three-dimensional view of a guide bar of the present invention;
[0039] Fig.12 It is a schematic diagram of the protective cover of the present invention.
[0040] List of reference numerals:
[0041] 1. Door bottom plate; 11. Guide strip; 12. Guide groove; 121. Vertical section; 122. Inclined section; 13. Guide column; 14. Guide bushing; 15. Screw rear support;
[0042] 2. Door body; 21. Door panel; 22. Support plate; 23. Door seat; 24. Door body fixing seat; 25. Push block;
[0043] 3. Screw assembly; 31; motor; 32. screw; 33. screw nut;
[0044] 41. Guide bearing; 42. Limit universal ball;
[0045] 5. Protective cover. DETAILED DESCRIPTION
[0046] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. Those skilled in the art can make adjustments to them as needed to adapt to specific application scenarios. For example, although the present application is described with the automatic sealing door of the sample library, it can also be applied to other fields that require a sealed door. The present invention does not impose any restrictions on the application scenarios of the sealed door and all fall within the scope of protection of the present invention.
[0047] It should be noted that in the description of the present invention, the terms "upper", "lower", "left", "right", "vertical", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.
[0048] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0049] Reference Figure 1 , in order to solve the problem that the existing sealed door is easy to get stuck or cannot be opened and closed in a low-temperature use environment. The sealed door of the present invention includes a door bottom plate 1, a door body 2 and a screw assembly 3. The screw assembly 3 includes a screw 32 and a screw nut 33 that moves in cooperation with the screw 32. The screw nut 33 is connected to the door body 2, and the screw 32 is connected to the door bottom plate 1. An opening is provided on the door bottom plate 1. When the screw 32 rotates, the screw nut 33 drives the door body 2 to move along the direction of the screw 32 to open and close the opening. Among them, at least the internal thread of the screw nut 33 or the entire screw nut 33 is made of a first plastic material.
[0050] Due to the large temperature difference between the inside and outside of the door body 2, the thermal conductivity of metal materials is stronger than that of non-metal materials. Therefore, the inventors found that when there is a certain amount of water vapor in the air, the metal material can quickly conduct the surrounding heat, so that its own temperature drops rapidly to close to the ambient temperature, and the surface temperature of the metal object exposed to the air can reach equilibrium with the ambient temperature in a short time. Therefore, when two metal parts are in contact in a low temperature environment, it is very easy to get stuck due to frost, increase resistance, and make the door body 2 difficult to open and close. In contrast, non-metallic plastic materials have slow thermal conductivity and the surface temperature drops relatively slowly, so they are not easy to frost. Therefore, setting the internal thread of the lead screw nut 33 or the entire lead screw nut 33 to a non-metallic plastic material can make it difficult to frost between the lead screw nut 33 and the lead screw 32, thereby making the resistance and wear smaller when opening and closing the door body 2, so that the door body 2 can be opened and closed smoothly in a low temperature environment.
[0051] Optionally, the material of the lead screw nut 33 is a low-temperature resistant plastic material that can maintain stable performance in a low-temperature environment of -80°C and will not become brittle or lose strength due to temperature drop. For example, the low-temperature resistant plastic material can be a polyolefin plastic, such as polyethylene (PE), which has excellent low-temperature resistance. It can still maintain good toughness and mechanical strength in a low-temperature environment of -100°C and is not prone to brittleness. For another example, the low-temperature resistant plastic material can also be polyetheretherketone (PEEK) plastic, which is a high-performance special plastic with excellent low-temperature resistance. It can still maintain high mechanical properties and wear resistance at extremely low temperatures of -100°C. In addition to the above embodiments, the low-temperature resistant plastic material can also be polytetrafluoroethylene (PTFE), ultra-high molecular weight polyethylene (UHMW-PE), etc. Those skilled in the art can set the material of the lead screw nut 33 according to the actual working environment temperature, as long as it can ensure the strength and wear resistance in a low-temperature environment, and all fall within the scope of protection of the present invention.
[0052] In addition, the above-mentioned low-temperature resistant plastic material also contains fillers and reinforcing agents that enable the lead screw nut 33 to run without lubricants and with low friction. For example, the filler can be graphite, molybdenum disulfide, etc. Adding the filler to the plastic can significantly reduce the friction coefficient of the plastic, so that it can achieve low-friction operation without lubricants. The reinforcing agent can be carbon fiber, glass fiber or polytetrafluoroethylene, etc., so as to improve the mechanical strength and hardness of the plastic, while improving the friction properties of the composite material and reducing deformation and wear caused by friction. Alternatively, nanomaterials, such as silicon dioxide, aluminum oxide, etc., can also be added to the low-temperature resistant plastic material to form a special interface structure to reduce the friction coefficient.
[0053] Reference Figure 1 and Figure 2 In a possible embodiment, the sealed door of the present invention comprises a door bottom plate 1, a door body 2 and a screw assembly 3. The door bottom plate 1 is provided with an opening, and the door body 2 is provided on the door bottom plate 1 so as to be movable up and down to open and close the opening. Figure 6 The door body 2 includes a door panel 21, a support plate 22 is provided on the upper and lower sides of the door panel 21, and a door seat 23 is provided on the left and right sides of the back of the door panel 21. To increase the strength, the door seat 23 and the support plate 22 are connected in sequence.
[0054] The lead screw assembly 3 is an electric lead screw. Figure 1 The electric lead screw comprises a motor 31, a lead screw 32 drivingly connected to the motor 31, and a lead screw nut 33 cooperating with the lead screw 32. The motor 31 is fixedly arranged on the upper part of the door bottom plate 1.
[0055] Next refer to Figure 7 and Figure 8Further, the sealing door further comprises a door body fixing seat 24 and a push block 25. The door body fixing seat 24 is arranged on the support plate 22 at the upper part of the door body 2. The lead screw nut 33 is fixed on the push block 25.
[0056] Reference Figure 4 and Figure 5 The door body fixing seat 24 is provided with a guide column 13 protruding outward, and the push block 25 is provided with a guide hole matched with the guide column 13. The push block 25 is connected to the door body fixing seat 24 through the guide column 13, and the guide column 13 can slide along the front and rear direction of the guide hole (the direction close to the door bottom plate or away from the door bottom plate). When the motor 31 drives the lead screw 32 to rotate, the lead screw nut 33 drives the push block 25 to move up and down along the lead screw 32, so as to drive the door body 2 to move up and down.
[0057] Further, a guide sleeve 14 is arranged in the guide hole, and the guide sleeve 14 is made of the second plastic material. The guide sleeve 14 is arranged to be made of plastic material, which can reduce frost, thereby reducing the sliding resistance between the guide column 13 and the guide sleeve 14, and preventing jamming.
[0058] Further, continue to refer to Figure 1 and Figure 2 Guide bars 11 are respectively arranged on the left and right sides of the opening of the door bottom plate 1. A lead screw rear support 15 is arranged between the guide bars 11 on both sides, and the lower end of the lead screw 32 abuts against the lead screw rear support 15 to provide certain support for the lead screw 32 without affecting the rotation of the lead screw 32.
[0059] Reference Figure 3 and Fig.11 , a guide groove 12 is provided on the guide bar 11, and guide bearings 41 matching the guide groove 12 are provided on the door seats 23 on both sides of the door body 2. The guide bearings 41 are embedded in the guide grooves 12, and when the door body 2 moves up and down, the guide bearings 41 are restricted by the guide grooves 12 and move along the guide grooves 12, thereby ensuring the stability of the door body 2 when moving. Specifically, the guide bearings 41 include an outer ring and an inner ring, and the outer ring is rotatably arranged on the outer periphery of the inner ring.
[0060] Of course, those skilled in the art may replace the guide bearing 41 as needed. For example, the guide bearing 41 may also be a guide wheel. As long as it is a guide rotating part that can reduce friction by rotating and play a guiding role, it falls within the protection scope of the present invention.
[0061] Reference Figure 3Furthermore, the door seats 23 on both sides of the door body 2 are provided with limit universal balls 42. Specifically, the limit universal balls 42 include a mounting seat and a ball, and the ball is freely rotatably arranged on the mounting seat. The limit universal balls 42 abut against the guide bars 11. When the door is opened or closed, the ball rolls along the guide bars 11 to limit the range of movement of the door body 2 between the guide bars 11.
[0062] Furthermore, the rotating part of the guide bearing 41 is made of a second plastic material. The rotating part of the guide bearing 41 is set to a plastic material, which can also reduce frost on the guide bearing 41 when it moves in the guide groove 12, thereby reducing the risk of the guide bearing 41 getting stuck when rotating.
[0063] Furthermore, a groove is formed at a position of the guide bar 11 close to the guide groove 12, and a heating wire (not shown in the figure) is arranged in the groove to heat and defrost the guide groove 12. However, it should be noted that although the present invention is described with a heating wire, the heating of the guide groove 12 can also be carried out by other types of heating elements, such as a heating plate, a heating rod, etc. In addition, the setting position of the heating element can also be set by those skilled in the art as needed, as long as it can conduct heat to the guide groove 12, and all fall within the protection scope of the present invention.
[0064] Furthermore, a sealing strip is provided between the door panel 21 and the door bottom plate 1. Fig.11 The guide groove 12 includes a vertical section 121 and an inclined section 122. The inclined section 122 is arranged at the lower part of the guide bar 11. Figures 7 to 10 , Figure 7 and Figure 8 This is a schematic diagram of the door body 2 when it is opened. Fig. 9 yes Fig.10 It is a schematic diagram of the door body 2 being closed. When the door body 2 slides downward to close, the guide bearing 41 enters the inclined section 122 from the vertical section 121, and the guide column 13 slides backward along the guide hole, so that the door panel 21 moves toward the door bottom plate 1, thereby enabling the door panel 21 and the door bottom plate 1 to be pressed tightly to ensure a sealing effect.
[0065] Reference Fig.12 Furthermore, a protective cover 5 is provided on the outer peripheral cover of the electric lead screw, and the protective cover 5 is connected to the door bottom plate 1. The protective cover 5 can protect the lead screw 32 and the transmission position between the lead screw 32 and the motor 31. The frost of the hot and humid air preferentially adheres to the protective cover 5, thereby preventing the lead screw 32 and the transmission position between the lead screw 32 and the motor 31 from frosting, and reducing the influence of condensation on the internal moving parts.
[0066] Optionally, the second plastic material may be the same as or different from the first plastic material. Those skilled in the art may set the second plastic material according to actual needs, and all of them fall within the protection scope of the present invention.
[0067] It should also be noted that the door body fixing seat 24 can be detachably connected to the support plate 22, or the door body fixing seat 24 and the support plate 22 can be integrally formed. Technical personnel in this field can set the door body fixing seat 24 according to their needs, and all of them fall within the protection scope of the present invention.
[0068] The following is a detailed description of the opening and closing process of the sealed door:
[0069] Reference Figure 7 and Figure 8 When the sealed door is in the open state, the door body 2 is located at the top, the guide bearing 41 is in the vertical section 121, and the front-to-back distance between the door panel 21 and the door bottom plate 1 is large. Fig. 9 and Fig.10 When the sealed door is closed, the motor 31 is turned on, the screw 32 rotates in the first direction, the screw nut 33 drives the push block 25 to move downward, and the guide bearing 41 moves in the vertical section 121 of the guide groove 12. At the same time, the door body 2 gradually moves downward. After moving a certain distance, the guide bearing 41 enters the inclined section 122. At the same time, the guide column 13 on the door body fixing seat 24 slides along the guide shaft sleeve 14 toward the door bottom plate 1, and the door body 2 slides a certain distance toward the door bottom plate 1 until the door body 2 is completely closed. At this time, the door panel 21, the door bottom plate 1 and the sealing strip are pressed tightly.
[0070] When the sealed door is opened, the motor 31 is turned on, the screw 32 rotates in the second direction, the screw nut 33 drives the push block 25 to move upward, and the guide bearing 41 moves in the inclined section 122 of the guide groove 12. While the door body 2 moves upward, the guide column 13 on the door body fixing seat 24 slides along the guide shaft sleeve 14 in the direction away from the door bottom plate 1, and the door body 2 slides a certain distance in the direction away from the door bottom plate 1, thereby preventing the friction resistance between the door body 2 and the door bottom plate 1 from being too large. After moving a certain distance, the guide bearing 41 enters the vertical section 121, and the door body 2 continues to move upward until the door body 2 is fully opened.
[0071] In summary, the sealed door of the present invention uses wear-resistant non-metallic plastic materials for the lead screw nut 33, the guide bearing 41 and the guide sleeve 14 that are in contact with and move relative to the metal parts, thereby reducing frost adhesion and reducing the risk of frosting and jamming of the moving parts in low-temperature environments. In addition, by adding electric heating defrosting near the guide groove 12 and adding metal shields outside the key moving parts, the impact of frost on the moving parts is further reduced. The present invention also generates relative sliding between the guide column 13 and the push block 25, so that the door body 2 can move forward and backward relative to the door bottom plate 1, thereby ensuring the compression and loosening between the door body 2 and the sealing strip, which can not only ensure the sealing, but also reduce the friction resistance during opening and closing.
[0072] As stated in the first paragraph of this section, the above implementation mode is only used to illustrate the principles of the present invention and is not intended to limit the scope of protection of the present invention. Without departing from the principles of the present invention, those skilled in the art can adjust the above structure so that the present invention can be applied to more specific application scenarios.
[0073] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.
Claims
1. A sealed door, characterized in that: The sealed door includes a door bottom plate, a door body and a screw assembly, wherein the door bottom plate is provided with an opening, and the screw assembly includes a screw and a screw nut that moves in cooperation with the screw, wherein the screw nut is connected to the door body, and the screw is connected to the door bottom plate; wherein at least the internal thread on the screw nut or the entire screw nut is made of a first plastic material.
2. The sealing door according to claim 1, characterized in that: The first plastic material is one of polyethylene, polytetrafluoroethylene, polyetheretherketone, and ultra-high molecular weight polyethylene, or a mixture of more thereof.
3. The sealing door according to claim 1, characterized in that: Guide bars are arranged on both sides of the door bottom plate, guide grooves are arranged on the guide bars, and corresponding guide rotating parts are arranged on both sides of the door body. The guide rotating parts are embedded in the guide grooves and slide along the guide grooves when the door body is opened or closed.
4. The sealing door according to claim 3, characterized in that: The guide groove includes a vertical section and an inclined section, and the sealed door also includes a door body fixing seat and a push block, the screw nut is fixed on the push block, the door body fixing seat is fixed on the door body, the push block is provided with a guide hole, and the door body fixing seat is provided with a guide column matching the guide hole, and the guide column can slide in the guide hole, so that after the door body enters the inclined section from the vertical section, the door body can slide toward the direction of the door bottom plate, so that the door body is closer to the door bottom plate to enhance the sealing.
5. The sealing door according to claim 3, characterized in that: A heating element is arranged on the guide bar.
6. The sealing door according to claim 3, characterized in that: Limiting universal balls are also arranged on both sides of the door body, and the limiting universal balls roll along the guide bars when the door body moves.
7. The sealing door according to claim 4, characterized in that: A guide sleeve is arranged in the guide hole, and the guide column slides in the guide sleeve.
8. The sealing door according to claim 3, characterized in that: The door body comprises a door panel, door seats are arranged on both sides of the door panel, and the guide rotating member is arranged on the door seats.
9. The sealing door according to claim 7, characterized in that: The guide sleeve and / or the rotating part of the guide rotating member are made of a second plastic material.
10. The sealing door according to any one of claims 1 to 9, characterized in that: The screw outer cover is provided with a protective cover, and the protective cover is connected to the door bottom plate.