A corrosion-resistant and safe gantry crane room rear door

Abstract

This utility model relates to the field of doors, specifically disclosing a corrosion-resistant and safe door machine room back door, including a mounting frame with an entrance opening on the mounting frame. A top-mounted slide rail is fixedly connected to the top of the mounting frame, and a bottom-mounted slide rail is fixedly connected to the bottom of the mounting frame. Two sets of sliding door mechanisms for opening and closing the entrance are installed between the top-mounted slide rail and the bottom-mounted slide rail, solving the technical problem of inconvenient replacement of rollers in existing sliding door systems.

Description

Technical Field

[0001] This utility model relates to the field of doors, and specifically discloses a corrosion-resistant and safe door machine room back door. Background Technology

[0002] In port operations, the rear door of the gantry crane room plays a crucial role. The rear door of the gantry crane room mainly adopts a movable sliding rail door design. This design plays an irreplaceable role in the daily maintenance of the gantry crane, especially in the replacement of wire ropes and the operation of various hoisting items, and provides great convenience for the maintenance of equipment in the room and the hoisting of items.

[0003] For example, utility model patent CN205778108U discloses a sliding door, in which a slide rail is provided on the upper and lower inner surfaces of the door frame, and at least two door panels are provided inside the door frame, with the upper and lower end faces of the door panels slidingly engaged with the slide rail. A slide rod is provided inside the door frame, parallel to the slide rail, with both ends of the slide rod fixedly connected to the left and right sides of the door frame, and the slide rod slidably passing through the door panel. Each slide rod is provided with two stop components, and the door panel is located between the two stop components. The stop components are slidably engaged with the slide rod, and the stop components have a limiting part for contacting the door panel. A fixing part is provided on the slide rod or slide rail, for connecting with the stop components to fix the stop components on the slide rail. Under the action of the two stop components, the door panel cannot move, thus fixing the door panel in an open position, and the sliding door is in a fixed open range. This avoids the problem of accidentally touching the door panel causing the opening range of the sliding door to become larger or smaller.

[0004] The existing device only solves the problem of abnormal opening range of sliding door caused by accidental contact with the door panel. However, it is inconvenient when the rollers on the door panel are damaged or worn out and need to be replaced. The door panel must be removed first to replace the rollers. This process is not only cumbersome and complicated, but also consumes a lot of manpower and time. In addition, the door panel is usually quite heavy, and accidents are prone to occur during the disassembly process, posing a threat to the personal safety of the operator. Utility Model Content

[0005] In view of this, the purpose of this utility model is to provide a corrosion-resistant and safe gantry crane room back door to solve the technical problem that it is inconvenient to replace the rollers of existing sliding door.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a corrosion-resistant and safe gantry crane room rear door, including a mounting frame with an entrance opening on the frame. A top-mounted sliding rail is fixedly connected to the top of the mounting frame, and a bottom-mounted sliding rail is fixedly connected to the bottom of the frame. Two sets of sliding door mechanisms for opening and closing the entrance are installed between the top-mounted and bottom-mounted sliding rails. The sliding door mechanism adopts a double-rail layout of top-mounted and bottom-mounted sliding rails, which effectively reduces the risk of door swaying and offset compared to traditional single-rail sliding doors.

[0007] Furthermore, the sliding door mechanism includes a door panel, which is slidably fitted into the mounting frame. A movable frame is fixedly connected to the door panel. A first movable plate is slidably fitted below the movable frame, and the first movable plate is provided with two ground axis rollers that contact the ground axis slide rail. A second movable plate is slidably fitted above the movable frame, and the second movable plate is provided with two top axis rollers that contact the top axis slide rail. A ground axis lifting and fixing device is installed on the first movable plate for disengaging the two ground axis rollers from contact with the ground axis slide rail, and a top axis lifting and fixing device is installed on the second movable plate for disengaging the two top axis rollers from contact with the top axis slide rail. Through the coordinated action of the ground axis lifting and fixing device and the top axis lifting and fixing device, the first movable plate and the second movable plate can be moved simultaneously, realizing the rapid disengagement of the ground axis rollers and top axis rollers from the corresponding slide rails. The replacement of the ground axis rollers and top axis rollers can be completed without disassembling the door panel. The operation is simple and convenient, saving time and effort, effectively avoiding the safety hazards and manpower waste caused by door panel disassembly, and significantly improving maintenance efficiency and safety.

[0008] Furthermore, the sliding door mechanism also includes a handle, which is fixedly connected to the moving frame. When opening or closing the door panel, the operator can directly apply force through the handle, thereby driving the moving frame and the first and second moving plates connected to it to move synchronously, achieving smooth sliding of the door panel.

[0009] Furthermore, the ground axis lifting and fixing device includes a first hydraulic rod, which is fixedly connected within the movable frame. A first pulling plate is provided at the telescopic end of the first hydraulic rod, and the first pulling plate is fixedly connected to the first movable plate. A first toothed rail is provided on one side of the first pulling plate. A first fixing block is slidably mounted below the second movable plate. A second toothed rail that can mesh with the first toothed rail is provided on the first fixing block. A first limiting plate is fixedly connected below the second movable plate. A first threaded rod is provided on the first fixing block. One end of the first threaded rod is rotatably connected to the first fixing block, and the other end of the first threaded rod is threadedly connected to the first limiting plate. A first long rod is provided on the first movable plate, and a first auxiliary wheel that can contact the top axis slide rail is installed on the first long rod. In the aforementioned ground axis lifting and fixing device, the telescopic end of the first hydraulic rod drives the first pulling plate to move vertically, causing the first moving plate to rise and disengage the ground axis roller from the ground axis slide rail. Simultaneously, the first auxiliary wheel on the first long rod rises synchronously and contacts the top axis slide rail, forming a temporary support. This ensures that the door panel remains balanced when the roller disengages from the slide rail, preventing structural deformation caused by unilateral suspension. During the replacement of the ground axis roller, the door panel does not need to be disassembled; maintenance can be completed simply by operating the lifting device, significantly reducing downtime. Furthermore, by rotating the first threaded rod to adjust the position of the first fixing block, the second gear rail engages and locks with the first gear rail. This ensures that the first moving plate remains fixed even after the hydraulic rod stops working, completely solving the energy consumption problem of traditional hydraulic devices requiring continuous power supply to maintain the lifting position. Compared to the complex structures of existing technologies that rely on manual bolt lifting or long-term hydraulic pressure maintenance, this solution utilizes a mechanical self-locking mechanism of toothed rail engagement and threaded limit, reducing energy consumption and improving long-term stability. Furthermore, the contact design between the auxiliary wheel and the top-mounted guide rail further disperses the localized pressure of the door panel's weight on the guide rail, reducing wear. This integrated lifting and locking system combines the advantages of efficient maintenance, energy saving, and structural protection.

[0010] Furthermore, the lifting and fixing device for the top shaft includes a second hydraulic rod, which is fixedly connected within the movable frame. A second pulling plate is provided at the telescopic end of the second hydraulic rod, and the second pulling plate is fixedly connected to the second movable plate. A third toothed rail is provided on one side of the second pulling plate. A second fixing block is slidably mounted above the first movable plate. A fourth toothed rail that can mesh with the third toothed rail is provided on the second fixing block. A second limiting plate is fixedly connected to the first movable plate. A second threaded rod is provided on the second fixing block. One end of the second threaded rod is rotatably connected to the second fixing block, and the other end of the second threaded rod is threadedly connected to the second limiting plate. A second long rod is provided on the second movable plate, and a second auxiliary wheel that can contact the ground shaft slide rail is installed on the second long rod. Compared to the limitations of traditional machine room door roller maintenance, which requires complete disassembly or relies on step-by-step operations, the top shaft lifting and fixing device uses a second hydraulic rod to drive a second pulling plate to move vertically, causing a second moving plate to rise and disengage the top shaft roller from the top shaft slide rail. Simultaneously, the second auxiliary wheel on the second long rod descends to contact the ground shaft slide rail. Meanwhile, the first hydraulic rod of the ground shaft lifting and fixing device simultaneously drives the first moving plate to rise, disengaging the ground shaft roller from the ground shaft slide rail. At this point, the first auxiliary wheel rises to contact the top shaft slide rail. Through the bidirectional temporary support of the first and second auxiliary wheels, both the top and ground shaft rollers simultaneously disengage from the slide rail and rotate. By shifting the load and forming a stable balance structure, operators can replace the top or bottom rollers without disassembling the door panel, significantly reducing maintenance costs and time. During replacement, rotating the second threaded rod pushes the second fixed block to slide, causing the fourth and third toothed rails to engage and lock. This ensures that the second moving plate remains fixed even after the second hydraulic rod stops supplying power. Combined with the synchronous engagement of the first and second toothed rails, a two-way mechanical self-locking mechanism is formed, completely eliminating the redundant design of traditional hydraulic systems that require continuous pressure maintenance or rely on external locks. This solves the technical problem of inconvenient roller replacement in existing sliding door systems.

[0011] The working principle and beneficial effects of this solution are as follows:

[0012] When it is necessary to replace the ground axle roller and top axle roller on the door panel, activate the first and second hydraulic rods in the moving frame and keep the current extension stroke unchanged. Rotate the second threaded rod counterclockwise to drive the second fixed block to move away from the second pull plate in the second slide groove, so that the fourth toothed rail and the third toothed rail are disengaged. Similarly, rotate the first threaded rod counterclockwise to disengage the second toothed rail on the first fixed block from the first toothed rail on the first pull plate. Then, the first hydraulic rod drives the first moving plate to move away from the bottom plate, and the second hydraulic rod drives the second moving plate to move closer to the bottom plate, so that the ground axle roller disengages from the ground axle slide rail. At the same time, the first hydraulic rod... The first auxiliary wheel on a long rod gradually contacts the top axis slide rail; when the second hydraulic rod moves, it drives the second moving plate downward via the second pulling plate, causing the top axis roller to disengage from the top axis slide rail. Simultaneously, the second auxiliary wheel on the second long rod gradually contacts the bottom axis slide rail. After the first auxiliary wheel and the top axis slide rail, and the second auxiliary wheel and the bottom axis slide rail, are fully in contact, the bottom axis roller and the top axis roller are completely disengaged from their respective slide rails. At this point, rotating the first and second threaded rods clockwise re-engages the first and second toothed rails, and the third and fourth toothed rails. The first and second hydraulic rods stop working, and the first and second moving plates are fixed in their positions. The first and second auxiliary wheels temporarily replace the top axis roller and the bottom axis roller, allowing the door panel to slide. This facilitates the replacement of the bottom axis roller and the top axis roller, solving the technical problem of inconvenient roller replacement in existing sliding door systems.

[0013] Other advantages, objectives, and features of this invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination and study, or may be learned from practice of this invention. The objectives and other advantages of this invention can be realized and obtained through the following description. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of an embodiment;

[0015] Figure 2 This is a schematic diagram of the sliding door mechanism in the embodiment;

[0016] Figure 3 The image shows an exploded view of the mounting frame, the top axis slide rail, and the bottom axis slide rail in the embodiment.

[0017] Figure 4 This is an exploded view of the ground axis lifting and fixing device and the top axis lifting and fixing device in the embodiment;

[0018] Figure 5 This is a schematic diagram of the structure of the first threaded rod, the first limiting plate, the first fixing block, the second threaded rod, the second limiting plate, and the second fixing block in the embodiment.

[0019] Figure 6 This is a schematic diagram of the structure of the first and second movable plates in the embodiment;

[0020] Figure 7 Figure 5 Enlarged view of point A in the middle;

[0021] Figure 8 Figure 5 Enlarged diagram of point B in the middle.

[0022] The following are the markings in the attached diagram: base plate 1, mounting frame 2, top axis slide rail 3, bottom axis slide rail 4, entrance 5, door panel 6, moving frame 7, handle 8, first moving plate 9, first mounting plate 10, bottom axis roller 11, second moving plate 12, second mounting plate 13, top axis roller 14, first moving groove 15, second moving groove 16, first hydraulic rod 17, first connecting plate 18, first pulling plate 19, first fixing block 20, first limiting plate 21, first threaded rod 22, first long rod 23, first auxiliary wheel 24, first gear rail 25, second gear rail 26, first slide groove 27, second hydraulic rod 28, second connecting plate 29, second pulling plate 30, second fixing block 31, second limiting plate 32, second threaded rod 33, second long rod 34, second auxiliary wheel 35, second slide groove 36, third gear rail 37, fourth gear rail 38. Detailed Implementation

[0023] The following detailed description illustrates the specific implementation method:

[0024] Example

[0025] like Figures 1 to 8 As shown, a corrosion-resistant and safe gantry crane room rear door is disclosed, including a base plate 1, a mounting frame 2, a top axis slide rail 3, a bottom axis slide rail 4, and two sets of sliding door mechanisms. The mounting frame 2 is provided on the base plate 1, and an entrance 5 is provided on the mounting frame 2, which passes through the mounting frame 2. The top axis slide rail 3 is fixedly connected to the upper inner wall of the mounting frame 2, and the bottom axis slide rail 4 is fixedly connected to the end of the mounting frame 2 away from the top axis slide rail 3. Two sets of sliding door mechanisms are provided between the top axis slide rail 3 and the bottom axis slide rail 4, and the two sets of sliding door mechanisms are used to open and close the entrance 5.

[0026] like Figure 1 As shown, the sliding door mechanism includes a door panel 6, a movable frame 7, a handle 8, a first movable plate 9, two first mounting plates 10, two ground axle rollers 11, a second movable plate 12, two second mounting plates 13, two top axle rollers 14, a ground axle lifting and fixing device, and a top axle lifting and fixing device. The door panel 6 is slidably mounted inside the mounting frame 2. The length of the door panel 6 is greater than the length of the entrance 5. The movable frame 7 is fixedly connected to the door panel 6. The movable frame 7 runs vertically through the door. The movable frame 7 has a first movable groove 15 and a second movable groove 16 on both sides. The handle 8 is fixedly connected to the movable frame 7.

[0027] like Figure 2 and Figure 3 The movable frame 7 shown has a slidable first movable plate 9. Two first mounting plates 10 are fixedly connected to the first movable plate 9. Two ground shaft rollers 11 are rotatably connected to the two first mounting plates 10. Both ground shaft rollers 11 are slidably connected to the ground shaft slide rail 4. A slidable second movable plate 12 is provided at one end of the movable frame 7 near the top shaft slide rail 3. Two second mounting plates 13 are fixedly connected to the second movable plate 12. Two top shaft rollers 14 are rotatably connected to the two second mounting plates 13. Both top shaft rollers 14 are slidably connected to the top shaft slide rail 3. A ground shaft lifting and fixing device is installed on the first movable plate 9. The ground shaft lifting and fixing device is used to disengage the two ground shaft rollers 11 from the ground shaft slide rail 4. A top shaft lifting and fixing device is installed on the second movable plate 12. The top shaft lifting and fixing device is used to disengage the two top shaft rollers 14 from the top shaft slide rail 3.

[0028] like Figure 4 As shown, the ground shaft lifting and fixing device includes a first hydraulic rod 17, a first connecting plate 18, a first pulling plate 19, a first fixing block 20, a first limiting plate 21, a first threaded rod 22, a first long rod 23, and a first auxiliary wheel 24. The first hydraulic rod 17 is fixedly connected inside the movable frame 7. The telescopic end of the first hydraulic rod 17 is vertically upward. The telescopic end of the first hydraulic rod 17 is fixedly connected to the first connecting plate 18. The first pulling plate 19 is fixedly connected to the first connecting plate 18. The first pulling plate 19 is fixedly connected to the first movable plate 9.

[0029] like Figure 5 , Figure 6 and Figure 7 As shown, a first toothed rail 25 is provided on one side of the first pull plate 19, and a first sliding groove 27 is provided below the second moving plate 12. A first slidable fixed block 20 is provided in the first sliding groove 27. A second toothed rail 26 is provided on the first fixed block 20. The second toothed rail 26 can mesh with the first toothed rail 25. A first limiting plate 21 is fixedly connected below the second moving plate 12. A first threaded rod 22 is rotatably connected to the side of the first fixed block 20 near the first limiting plate 21. The end of the first threaded rod 22 away from the first fixed block 20 is threadedly connected to the first limiting plate 21 and passes through the first moving groove 15. A first long rod 23 is fixedly connected to the first moving plate 9. A first auxiliary wheel 24 is rotatably connected to the end of the first long rod 23 near the top axis slide rail 3. The first auxiliary wheel 24 can slide with the top axis slide rail 3.

[0030] like Figure 5 , Figure 6 and Figure 8As shown, the lifting and fixing device of the top shaft includes a second hydraulic rod 28, a second connecting plate 29, a second pulling plate 30, a second fixing block 31, a second limiting plate 32, a second threaded rod 33, a second long rod 34, and a second auxiliary wheel 35. The second hydraulic rod 28 is fixedly connected inside the moving frame 7. The telescopic end of the second hydraulic rod 28 is vertically downward. The telescopic end of the second hydraulic rod 28 is fixedly connected to the second connecting plate 29. The second pulling plate 30 is fixedly connected to the second connecting plate 29. The second pulling plate 30 is fixedly connected to the second moving plate 12.

[0031] like Figure 4 As shown, a third toothed rail 37 is provided on one side of the second pull plate 30, a second slide groove 36 is provided above the first moving plate 9, a slidable second fixed block 31 is provided in the second slide groove 36, a fourth toothed rail 38 is provided on the second fixed block 31, the fourth toothed rail 38 can mesh with the third toothed rail 37, a second limiting plate 32 is fixedly connected above the first moving plate 9, a second threaded rod 33 is rotatably connected to the side of the second fixed block 31 near the second limiting plate 32, the end of the second threaded rod 33 away from the second fixed block 31 is threadedly connected to the second limiting plate 32 and passes through the second moving groove 16, a second long rod 34 is fixedly connected to the second moving plate 12, a second auxiliary wheel 35 is rotatably connected to the end of the second long rod 34 near the ground axis slide rail 4, the second auxiliary wheel 35 can slide with the ground axis slide rail 4.

[0032] In practice

[0033] Pushing the handle 8 on the movable frame 7 can move the door panel 6 between the ground axis slide rail 4 and the top axis slide rail 3 via the ground axis roller 11 and the top axis roller 14. The door panel 6 is moved by the handle 8 to open and close the entrance 5. The ground axis slide rail 4 and the top axis slide rail 3 are fixed by the mounting frame 2, and the mounting frame 2 is fixed by the base plate 1.

[0034] When it is necessary to replace the ground roller 11 and top roller 14 on the door panel 6, first activate the first hydraulic rod 17 and the second hydraulic rod 28 in the moving frame 7 to put them into working state and keep the current extension stroke unchanged.

[0035] By rotating the second threaded rod 33 on the second limiting plate 32 counterclockwise, since the second threaded rod 33 is threadedly connected to the second limiting plate 32, the counterclockwise rotation will cause the second fixing block 31 to move away from the second pulling plate 30 in the second slide groove 36. At this time, the fourth toothed rail 38 on the second fixing block 31 will stop engaging with the third toothed rail 37 on the second pulling plate 30. After rotating the second threaded rod 33 on the second limiting plate 32 counterclockwise, rotate the first threaded rod 22 on the first limiting plate 21 counterclockwise. Since the first threaded rod 22 is threadedly connected to the first limiting plate 21, the counterclockwise rotation will cause the first fixing block 20 to move away from the first pulling plate 19 in the first slide groove 27. At this time, the second toothed rail 26 on the first fixing block 20 will stop engaging with the first toothed rail 25 on the first pulling plate 19.

[0036] After the first gear 25 and the second gear 26 have finished meshing, and the third gear 37 and the fourth gear 38 have finished meshing, the first hydraulic rod 17 inside the moving frame 7 can be activated simultaneously to move the first connecting plate 18 away from the base plate 1, and the second hydraulic rod 28 to move the second connecting plate 29 closer to the base plate 1. When the first connecting plate 18 moves within the moving frame 7, it will cause the first pulling plate 19 to move upward. During the movement of the first pulling plate 19, it will cause the first moving plate 9 to move upward. When the first moving plate 9 moves, it will also drive the first threaded rod. 22. The first fixed block 20 and the first limiting plate 21 move. At this time, the first threaded rod 22 moves upward through the first moving groove 15. During the movement, the first moving plate 9 will drive the ground shaft roller 11 on the first mounting plate 10 to disengage from the ground shaft slide rail 4. At this time, the first long rod 23 on the first moving plate 9 will gradually move upward and approach the top shaft slide rail 3. During the movement, the first long rod 23 will drive the first auxiliary wheel 24 to gradually contact the top shaft slide rail 3. After the first auxiliary wheel 24 is completely in contact with the top shaft slide rail 3, the ground shaft roller 11 will also completely disengage from the ground shaft slide rail 4.

[0037] While the first hydraulic rod 17 moves the first connecting plate 18 away from the base plate 1, the second hydraulic rod 28 moves the second connecting plate 29 closer to the base plate 1. As the second hydraulic rod 28 moves the second connecting plate 29 downwards, the second connecting plate 29 moves the second pulling plate 30 downwards. When the second pulling plate 30 moves, it moves the second moving plate 12 downwards. The movement of the second moving plate 12 also moves the second threaded rod 33, the second fixing block 31, and the second limit... When the position plate 32 moves, the second threaded rod 33 moves upward through the second moving groove 16. During the movement, the second moving plate 12 will cause the upper shaft roller 14 on the second mounting plate 13 to disengage from the upper shaft slide rail 3. At this time, the second long rod 34 on the second moving plate 12 will gradually move downward and approach the ground shaft slide rail 4. When the second long rod 34 moves, it will cause the second auxiliary wheel 35 to contact the ground shaft slide rail 4. After the second auxiliary wheel 35 is fully in contact with the ground shaft slide rail 4, the upper shaft roller 14 will simultaneously completely disengage from the upper shaft slide rail 3.

[0038] After the first hydraulic rod 17 and the second hydraulic rod 28 drive the ground axis roller 11 and the top axis roller 14 to disengage from the ground axis slide rail 4 and the top axis slide rail 3, respectively, the first threaded rod 22 and the second threaded rod 33 are rotated clockwise, causing the previously disengaged first toothed rail 25, second toothed rail 26, third toothed rail 37, and fourth toothed rail 38 to re-engage. At this time, the first hydraulic rod 17 and the second hydraulic rod 28 stop working, so as to fix and limit the first moving plate 9 and the second moving plate 12. At this time, the first auxiliary wheel 24 and the second auxiliary wheel 35 play the role of fixing the door panel 6. The first auxiliary wheel 24 and the second auxiliary wheel 35 temporarily replace the function of the top axis roller 14 and the ground axis roller 11. At this time, the ground axis slide rail 4 and the top axis slide rail 3 can be replaced. At the same time, the door panel 6 can be slid by the first auxiliary wheel 24 and the second auxiliary wheel 35.

[0039] The above description is merely an embodiment of this utility model, and common knowledge such as specific structures and characteristics in the solution is not described in detail here. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of this utility model, and these should also be considered within the protection scope of this utility model. These modifications and improvements will not affect the effectiveness of the implementation of this utility model or its practicality.

Claims

1. A corrosion-resistant and safe gantry crane room rear door, characterized in that: The device includes a mounting frame with an entrance. A top-mounted slide rail is fixedly connected to the top of the mounting frame, and a bottom-mounted slide rail is fixedly connected to the bottom of the mounting frame. Two sets of sliding door mechanisms for opening and closing the entrance are installed between the top-mounted slide rail and the bottom-mounted slide rail.

2. The corrosion-resistant and safe gantry crane room rear door according to claim 1, characterized in that: The sliding door mechanism includes a door panel, which is slidably fitted into the mounting frame. A movable frame is fixedly connected to the door panel. A first movable plate is slidably fitted below the movable frame. The first movable plate is provided with two ground axis rollers that contact the ground axis slide rail. A second movable plate is slidably fitted above the movable frame. The second movable plate is provided with two top axis rollers that contact the top axis slide rail. A ground axis lifting and fixing device is installed on the first movable plate for disengaging the two ground axis rollers from contact with the ground axis slide rail. A top axis lifting and fixing device is installed on the second movable plate for disengaging the two top axis rollers from contact with the top axis slide rail.

3. The corrosion-resistant and safe gantry crane room rear door according to claim 2, characterized in that: The sliding door mechanism also includes a handle, which is fixedly connected to the movable frame.

4. The corrosion-resistant and safe gantry crane room rear door according to claim 2, characterized in that: The ground axis lifting and fixing device includes a first hydraulic rod, which is fixedly connected within the movable frame. A first pulling plate is provided at the telescopic end of the first hydraulic rod, and the first pulling plate is fixedly connected to the first movable plate. A first toothed rail is provided on one side of the first pulling plate. A first fixing block is slidably mounted below the second movable plate. A second toothed rail that can mesh with the first toothed rail is provided on the first fixing block. A first limiting plate is fixedly connected below the second movable plate. A first threaded rod is provided on the first fixing block. One end of the first threaded rod is rotatably connected to the first fixing block, and the other end of the first threaded rod is threadedly connected to the first limiting plate. A first long rod is provided on the first movable plate, and a first auxiliary wheel that can contact the top axis slide rail is installed on the first long rod.

5. The corrosion-resistant and safe gantry crane room rear door according to claim 4, characterized in that: The lifting and fixing device for the top shaft includes a second hydraulic rod, which is fixedly connected within the movable frame. A second pulling plate is provided at the telescopic end of the second hydraulic rod, and the second pulling plate is fixedly connected to the second movable plate. A third toothed rail is provided on one side of the second pulling plate. A second fixing block is slidably mounted above the first movable plate. A fourth toothed rail that can mesh with the third toothed rail is provided on the second fixing block. A second limiting plate is fixedly connected to the first movable plate. A second threaded rod is provided on the second fixing block. One end of the second threaded rod is rotatably connected to the second fixing block, and the other end of the second threaded rod is threadedly connected to the second limiting plate. A second long rod is provided on the second movable plate, and a second auxiliary wheel that can contact the ground shaft slide rail is installed on the second long rod.

Images