A rope compartment access device and its usage method

Abstract

The present invention relates to the technical field of shipbuilding, and discloses a rope cabin entrance and exit device and its use method, including a three-clamp opening and closing mechanism. The three-clamp opening and closing mechanism includes a main shaft, a clamp, and a locking limit block. The apron base is installed and fixed below the ship deck. The clamp and the locking limit block cooperate with each other. The locking limit block is located on the outer surface of the annular baffle. The annular baffle is composed of a plurality of arc-shaped baffles. There is an opening for clamping the clamp between the arc-shaped baffles. The clamp is located at one end of the main shaft, and the other end of the main shaft passes through the cover plate and is sleeved with a handle. To open the hatch cover: The handle is sleeved with the main shaft; rotate the handle, the handle drives the clamp, and the clamp reaches the opening; lift the lifting handle, remove the cover plate, and the opening is completed; the wear-resistant bushing is sleeved on the apron; To close the hatch cover: Remove the wear-resistant bushing; Place the cover plate above the apron; Sleeve the handle with the main shaft; Rotate the handle, limit the clamp, and the hatch cover is locked. This makes the hatch locking and sealing effect good, and reduces the wear generated when the rope enters and exits the hatch.

Description

Technical Field

[0001] The present invention relates to the technical field of shipbuilding, in particular to a rope compartment entrance and exit device and a use method thereof. Background Art

[0002] Ropes are one of the common equipment on ships. They are of various types and widely used. They are indispensable in the process of ship operations. Therefore, rope compartments are often installed on ships to store and manage ropes in an orderly manner. Since ropes are frequently used, the rope compartment hatch should be openable and closable at any time. The rope compartment hatch is often equipped with a hatch cover as the rope compartment entrance and exit device; traditional hatch covers are mostly protruding structures, and their overall structure protrudes above the deck surface, which not only occupies deck space, but also easily causes friction and collision with workers or equipment on the deck; ships now mostly use embedded hatch covers, that is, the main part is buried under the deck, saving deck space, but most embedded hatch covers cannot completely hide their entirety, and their locking mechanism often uses multiple clips or bolts, which is inconvenient to open and close. In addition, they often cannot effectively achieve hatch sealing.

[0003] Document CN2023116417273 discloses a hatch cover structure and proposes a buried hatch cover structure. In this solution, the hatch cover is embedded in a groove and flush with the deck, which can perfectly hide the hatch cover inside the deck. Its locking mechanism can effectively lock the hatch cover, and the hatch sealing effect is also relatively good. However, the hatch cover locking mechanism of this solution is still relatively complex, and the manufacturing cost of the hatch cover is high. If this hatch cover is used as an entrance and exit device for ropes to enter and exit the rope compartment, when it is open, one side of the hatch cover is hinged to the hinge seat, which may affect the entry and exit of ropes into the rope compartment. In addition, the rope compartment entrance and exit device must meet the requirements of reducing rope wear and ensuring smooth and smooth use of ropes in and out of the rope compartment. Therefore, this type of hatch cover is not entirely suitable as an entrance and exit device for rope compartments.

[0004] Therefore, a new technical solution is needed to solve the above technical problems. Summary of the invention

[0005] In order to solve the above problems, the present invention discloses a rope cabin entrance and exit device and a method of use thereof, which adopts a three-clamp opening and closing mechanism to achieve good hatch locking and sealing effects. This device has a simple structure, low cost, does not occupy deck space, and can effectively reduce the wear caused by ropes entering and exiting the hatch.

[0006] The technical solution of the present invention is as follows: A rope cabin entrance and exit device, including a cover plate, a surrounding plate, a three-clamp opening and closing mechanism, an anti-wear bushing, and a lifting handle. The three-clamp opening and closing mechanism includes a main shaft, a clamp, and a locking and limiting block. The base of the surrounding plate is fixedly installed under the ship's deck of the deck hatch. The clamp and the locking and limiting block cooperate with each other. The locking and limiting block is located on the outer surface of the annular baffle. The annular baffle is composed of multiple arc-shaped baffles. There is an opening for clamping the clamp between the arc-shaped baffles. The clamp is located at one end of the main shaft, and the other end of the main shaft passes through the cover plate and is sleeved with a handle.

[0007] By adopting the above technical solution, the clamp rotates, so that the clamp is located in the opening, thereby opening the cover plate, and then opening the hatch cover, so that the ropes inside can be taken out or put in. The clamp is located on the locking and limiting block, and the cover plate covers the surrounding plate to close the hatch.

[0008] Preferably, the locking and limiting block is integrally in the shape of a right trapezoidal block, and is sequentially arranged in a circular shape on one side of the annular baffle inside the surrounding plate. The locking and limiting block includes a slope, a platform, and a small limiting block. The slope and the small limiting block are located on both sides of the platform. The small limiting block is vertically located on the side of the right-angled side of the platform, and the downward trend of the slope is towards a position away from the small limiting block.

[0009] By adopting the above technical solution, the locking and limiting block plays a role in limiting the clamp. When the clamp rotates to the position of the locking and limiting block, the clamp climbs up from the slope. When it reaches the platform, the small limiting block plays a role in limiting the clamp, preventing the clamp from moving infinitely outwards, so that the sealing strip inside the cover plate closely adheres to the surrounding plate to cover the hatch.

[0010] Preferably, a square annular groove is provided in the circumference of the end plate of the cover plate, and a sealing strip is embedded in the square annular groove. The sealing strip abuts against the surrounding plate below, and a square annular groove body with a shape opposite to that of the square annular groove is provided in the circumference of the end of the surrounding plate, and the inner side edge of the square annular groove body abuts against the sealing strip.

[0011] By adopting the above technical solution, when the sealing strip inside the cover plate presses against the surrounding plate, it means that the cover plate has a downward acting force on the surrounding plate, and the cover plate is tightly abutted against the surrounding plate to seal the hatch.

[0012] Preferably, the arc-shaped baffle is adapted to the circumference of the surrounding plate, the side is perpendicular to the surrounding plate, the number of the arc-shaped baffle and the clamp is the same, and the arc-shaped baffles are arranged at intervals, that is, the interval between the arc-shaped baffles is the opening.

[0013] By adopting the above technical solution, the arc-shaped baffle is arc-shaped and adapted to the surrounding plate, and is located on the side of the surrounding plate. The setting of the arc-shaped baffle makes the locking and limiting block have a fixed position to support the clamp.

[0014] Preferably, a sealing member is snap-fitted around the part of the main shaft passing through the cover plate. A bushing is sleeved on the part of the main shaft below the cover plate. The clamping buckles are evenly distributed on the bushing and are in interference fit with the bushing. The bushing is locked on the main shaft by fasteners, nuts and washers.

[0015] By adopting the above technical solution, the sealing member can ensure the sealing between the main shaft and the cover plate. When the main shaft is rotated by the handle, the clamping buckles also rotate accordingly.

[0016] Preferably, the clamping buckle is in the shape of a long rod. The end of the clamping buckle is located on the locking limit block and does not exceed the inner side surface of the square annular groove. The clamping buckle is located at the opening position. The apron and the sealing strip are in contact, but the sealing strip is not under stress.

[0017] By adopting the above technical solution, the clamping buckle is exactly located on the inner side surface of the square annular groove. When the clamping buckle is at the opening position and the handle is lifted upward, the cover plate can be lifted upward exactly. When the clamping buckle runs to the locking limit block, the cover plate is pressed against the apron.

[0018] Preferably, a square protrusion is provided above the part of the main shaft above the cover plate. A circular protrusion is provided at the bottom of the square protrusion. The size of the circular protrusion is larger than the size of the through groove of the cover plate and is exactly stuck on the upper part of the through groove. The square protrusion is sleeved with the sleeve at the bottom of the handle, and the handle is in an inverted L shape.

[0019] By adopting the above technical solution, the sleeve at the bottom of the handle is sleeved with the square protrusion at the top of the main shaft. The circular protrusion at the bottom of the square protrusion can prevent the handle from passing through the cover plate when the clamping buckle squeezes inward, so as to realize the extrusion of the cover plate. After the work is completed, the handle can be removed from the main shaft, and the whole device will not protrude from the surface of the ship deck.

[0020] Preferably, the wear-resistant bushing is in a barrel shape. The middle part of the wear-resistant bushing is in a cylindrical shape, and its diameter is adapted to the diameter of the annular baffle. The upper part of the cylindrical shape is a convex ring plate facing outward, and the bottom of the convex ring plate is snap-fitted on the ship deck above the apron.

[0021] By adopting the above technical solution, when the cover plate is removed from the apron and the wear-resistant bushing is sleeved on the apron, it can prevent the rope from damaging the apron when being taken out, and play a role in protecting the apron.

[0022] Preferably, the cover plate is provided with an inwardly concave square groove, and a lifting handle is arranged in the square groove.

[0023] By adopting the above technical solution, when there is no pressure between the cover plate and the apron, at this time, by lifting the lifting handle upward, the cover plate can be taken off from the apron more conveniently and quickly.

[0024] A method of using a rope cabin access device, comprising the following steps:

[0025] Opening the hatch cover:

[0026] Step 1: Socket the sleeve below the handle with the square protrusion above the main shaft;

[0027] Step 2: Rotate the handle, and the handle drives the main shaft so that the three clamping buckles rotate. The three clamping buckles slide down along the slope of the locking limit block and reach the opening position of the annular baffle inside the bulkhead;

[0028] Step 3: Lift the lifting handle upwards, take out the cover plate, and the hatch cover is opened completely

[0029] Step 4: Sleeve the anti-wear bushing on the bulkhead;

[0030] Closing the hatch cover:

[0031] S1: Remove the anti-wear bushing from above the bulkhead;

[0032] S2: Use the lifting handle to place the cover plate above the bulkhead, and align the sealing strip of the cover plate with the inner plate of the square annular groove of the bulkhead;

[0033] S3: Socket the sleeve below the handle with the square protrusion above the main shaft;

[0034] S4: Rotate the handle, and the handle drives the main shaft so that the three clamping buckles rotate. The three clamping buckles climb along the slope of the trapezoidal locking limit block and reach the small limit block of the locking limit block for limiting, and the hatch cover is locked completely.

[0035] Advantages of the present invention: 1. The hatch cover of the present invention adopts a fixed three-clamping buckle opening and closing mechanism. When closing the hatch, rotate the handle to make the clamping buckle press against the locking limit block. At the same time, the cover plate and the sealing strip are tightly pressed against the top of the bulkhead. Remove the handle from the main shaft, and the deck surface is almost flat without affecting others, realizing hatch sealing, simple and convenient operation, and strong hatch cover sealing performance.

[0036] 2. When the present invention needs to access the rope, only need to rotate the clamping buckle to the open position, then take down the cover plate as a whole from the bulkhead, and then sleeve on the anti-wear bushing. In this way, when the rope enters and exits, it can protect the bulkhead, there are no other obstacles near the rope, and it will not affect the rope's entry and exit from the hatch, improving the efficiency of the rope's entry and exit from the hatch.

[0037] 3. The hatch cover of the present invention adopts an embedded and separable design. The embedded design makes the whole hatch cover flush with the deck, does not occupy the deck space, and there is no need to set up an additional device to place the rope guiding device. The separable design makes the cover plate of the hatch cover separated from the base. After the hatch cover is opened, its cover plate can be taken away, which does not affect the rope's entry and exit from the rope cabin at all. Description of the Drawings

[0038] Figure 1 Schematic structural diagram of an embodiment of the present invention;

[0039] Figure 2 Top view of the hatch cover in the locked state;

[0040] Figure 3 Cross-sectional view of the lifting handle;

[0041] Figure 4 Bottom view of the hatch cover in the locked state;

[0042] Figure 5 Cross-sectional view of the wear-resistant bushing;

[0043] Figure 6 Cross-sectional view of the wear-resistant bushing in the working state.

[0044] Wherein: 1. Handle, 1-1. Sleeve, 2. Cover plate, 2-1. Square annular clamping groove, 2-2. Square groove, 3. Sealing strip, 4. Enclosure, 41. Square annular groove body, 42. Arc-shaped baffle, 5. Three-clamp opening and closing mechanism, 51. Main shaft, 51-1. Square protrusion, 51-2. Ring-shaped protrusion, 52. Fastener, 53. Nut, 54. Washer, 55. Bushing, 56. Seal, 57. Clamp, 58. Locking limit block, 58-1. Slope, 58-2. Platform, 58-3. Small limit block, 6. Lifting handle, 7. Wear-resistant bushing, 7-1. Convex ring plate, 8. Opening. Specific embodiments

[0045] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention.

[0046] As Figures 1-6 shown, a rope hatch entrance and exit device includes a cover plate 2, an enclosure 4, a three-clamp opening and closing mechanism 5, a wear-resistant bushing 7, and a lifting handle 6. The three-clamp opening and closing mechanism 5 includes a main shaft 51, a clamp 57, and a locking limit block 58. The base of the enclosure 4 is fixedly installed below the ship's deck of the deck hatch. The clamp 57 and the locking limit block 58 cooperate with each other. The locking limit block 58 is located on the outer surface of the annular baffle. The annular baffle is composed of a plurality of arc-shaped baffles 42. An opening 8 for clamping the clamp 57 is provided between the arc-shaped baffles 42. The clamp 57 is located at one end of the main shaft 51. The other end of the main shaft 51 passes through the cover plate 2 and is sleeved with the handle 1. The clamp 57 rotates, so that the clamp 57 is located at the opening 8, thereby opening the cover plate 2, and then opening the hatch cover, so that the internal rope can be taken out or put in. The clamp 57 is located on the locking limit block 58, and the cover plate 2 covers the enclosure 4 to close the hatch.

[0047] The locking limit block 58 is integrally in the shape of a right trapezoid and is sequentially arranged on one side of the annular baffle inside the enclosing plate 4 in a circular pattern. The locking limit block 58 includes a slope 58-1, a platform 58-2, and a small limit block. The slope 58-1 and the small limit block 58-3 are located on both sides of the platform 58-2. The small limit block 58-3 is perpendicularly located on the side of the right-angle side of the platform 58-2. The downward trend of the slope 58-1 is towards a position away from the small limit block 58-3. The locking limit block 58 plays a role in limiting the clip 57. When the clip 57 rotates to the position of the locking limit block 58, the clip 57 climbs up from the slope 58-1. When it climbs to the platform 58-2, the small limit block 58-3 plays a role in limiting the clip 57, preventing the clip 57 from extending infinitely outwards, so that the sealing strip 3 inside the cover plate 2 is closely attached to the enclosing plate 4 to cover the hatch. After the fastening is completed, the sleeve 1-1 of the handle 1 can also be removed from the main shaft 51 to ensure that the overall device is almost flat with the deck surface, without affecting the walking of the ship's crew and the stacking of other goods.

[0048] The end plate of the cover plate 2 is provided with a square annular card slot 2-1 around the circumference. A sealing strip 3 is embedded in the square annular card slot 2-1. The sealing strip 3 abuts against the enclosing plate below. The end of the enclosing plate 4 is provided with a square annular groove body 41 with a shape opposite to that of the square annular card slot 2-1. The inner side edge of the square annular groove body 41 abuts against the sealing strip 3. When the sealing strip 3 inside the cover plate 2 abuts against the enclosing plate 4, it means that the cover plate 2 has a downward acting force on the enclosing plate 4, and the cover plate 2 is tightly abutted against the enclosing plate 4 to seal the hatch.

[0049] The arc-shaped baffle 42 is adapted to the circumference of the enclosing plate 4, and its side is perpendicular to the enclosing plate 4. The number of arc-shaped baffles 42 is the same as that of the clips 57. The number of clips 57 is generally set to three, and it can also be set to other numbers according to the actual situation. The arc-shaped baffles 42 are arranged at intervals, that is, the interval between the arc-shaped baffles 42 is the opening 8. The arc-shaped baffles 42 are arc-shaped and adapted to the enclosing plate 4 and are located on the side of the enclosing plate 4. The setting of the arc-shaped baffles 42 enables the locking limit block 58 to have a fixed position to support the clip 57.

[0050] A sealing member 3 is clamped and sleeved on the part of the main shaft 51 passing through the cover plate 2. A bushing 55 is sleeved on the part of the main shaft 51 below the cover plate 2. The clips 57 are radially and evenly distributed on the bushing 55 with the bushing as the center and are in interference fit with the bushing 55. The bushing 55 is locked on the main shaft 51 through fasteners 52, nuts 53, and washers 54. The sealing member 3 can ensure the sealing between the main shaft 51 and the cover plate 2. When the main shaft 51 rotates through the handle 1, the clips 57 also rotate accordingly.

[0051] The clamping buckle 57 is in the shape of a long rod. The end of the clamping buckle 57 is located on the locking limit block 58 and does not exceed the inner side surface of the square annular groove body 41. The clamping buckle 57 is located at the opening position. The surrounding plate 4 and the sealing strip 3 are in contact, but the sealing strip 3 is not under force. The clamping buckle 57 is exactly located on the inner side surface of the square annular groove 2-1. When the clamping buckle 57 is located at the opening 8, when the handle 1 is lifted upwards, the cover plate 2 can be lifted upwards exactly. When the clamping buckle 57 runs to the locking limit block 58, the cover plate 2 is pressed towards the surrounding plate 4.

[0052] Above the part of the main shaft 51 located above the cover plate 2, there is a square protrusion 51-1. At the bottom of the square protrusion 51-1, there is a circular protrusion 51-2. The size of the circular protrusion 51-2 is larger than the size of the through groove 2-3 of the cover plate 2 and is exactly stuck in the upper part of the through groove 2-3. In this way, due to gravity, the main shaft 51 always faces downwards, and the top is stuck in the upper part of the through groove of the cover plate 2 due to the square protrusion 51-1, which is convenient for the sleeve 1-1 of the handle 1 to be sleeved. The square protrusion 51-1 and the sleeve 1-1 at the bottom of the handle 1 are sleeved. The handle 1 is in an inverted L shape. The sleeve 1-1 at the bottom of the handle 1 and the square protrusion 51-1 at the top of the main shaft 51 are sleeved. The circular protrusion 51-2 at the bottom of the square protrusion 51-1 can prevent the handle 1 from passing through the cover plate 2 when the clamping buckle 57 squeezes towards the inside, thereby realizing the extrusion of the cover plate 2. After the work is completed, the handle 1 can also be removed from the main shaft 51, and the whole device will not protrude from the surface of the ship's deck.

[0053] The wear-resistant bushing 7 is in a barrel shape. The middle part of the wear-resistant bushing 7 is in a cylindrical shape, and its diameter is adapted to the diameter of the annular baffle. The upper part of the cylindrical shape is a convex ring plate 7-1 facing outwards. The bottom of the convex ring plate 7-1 is clamped on the ship's deck above the surrounding plate 4. When the cover plate 2 is removed from the surrounding plate 4 and the wear-resistant bushing 7 is sleeved on the surrounding plate 4, it can prevent the rope from generating intense friction with the surrounding plate when the rope is taken out, thereby preventing the rope from damaging the surrounding plate 4 and playing a role in protecting the surrounding plate 4 and prolonging the service life of the surrounding plate 4.

[0054] The cover plate 2 is provided with an inwardly recessed square groove 2-2, and a lifting handle 6 is arranged in the square groove 2-2. When there is no pressure between the cover plate 2 and the surrounding plate 4, at this time, by lifting the lifting handle 6 upwards, it is convenient to take down the cover plate 2 from the surrounding plate 4 faster.

[0055] A usage method of a rope cabin entrance and exit device includes the following steps:

[0056] Open the hatch cover:

[0057] Step 1: Sleeve the lower sleeve 1-1 of the handle 1 with the upper square protrusion 51-1 of the main shaft 51;

[0058] Step 2: Rotate the handle 1. The handle 1 drives the main shaft 51, thereby rotating the three clamping clips 57. The three clamping clips 57 slide down along the slope 58-1 of the locking limit block 58 and reach the opening 8 of the annular baffle 42 inside the apron 4.

[0059] Step 3: Lift the lifting handle 6 upward to remove the cover plate 2, and the hatch cover is fully opened.

[0060] Step 4: Slip the wear-resistant bushing 7 onto the apron 4.

[0061] Closing the hatch cover:

[0062] S1: Remove the wear-resistant bushing 7 from above the apron 4.

[0063] S2: Use the lifting handle 6 to place the cover plate 2 above the apron 4. The sealing strip 3 of the cover plate 2 is aligned with the inner plate of the square annular groove body 41 of the apron 4.

[0064] S3: Socket the sleeve 1-1 below the handle 1 with the square protrusion 51-1 above the main shaft 51.

[0065] S4: Rotate the handle 1. The handle 1 drives the main shaft 51, thereby rotating the three clamping clips 57. The three clamping clips 57 climb along the slope 58-1 of the trapezoidal locking limit block 58 and reach the small limit block 58-3 of the locking limit block 58 for limiting, and the hatch cover is fully locked.

[0066] Those skilled in the art should understand that the embodiments of the present invention described above and shown in the drawings are only examples and do not limit the present invention. The object of the present invention has been fully and effectively achieved. The function and structural principle of the present invention have been demonstrated and explained in the embodiments. Without departing from the principle, any deformation or modification of the embodiments of the present invention is possible.

Claims

1. A rope hatch entrance device, comprising a cover plate, a surrounding plate, a three-clamp opening and closing mechanism, an anti-wear bushing and a lifting handle. The three-clamp opening and closing mechanism includes a main shaft, a clamp and a locking limit block. The base of the surrounding plate is fixedly installed under the ship's deck of the deck hatch. It is characterized in that: The clip and the locking limit block cooperate with each other. The locking limit block is located on the outer surface of the annular baffle. The annular baffle is composed of a plurality of arc-shaped baffles. An opening for clamping the clip is provided between the arc-shaped baffles. The clip is located at one end of the main shaft, and the other end of the main shaft passes through the cover plate and is sleeved with the handle. The locking limit block is integrally in a right trapezoidal block structure and is sequentially arranged in a circular shape on one side of the annular baffle within the surrounding plate. The locking limit block includes a slope, a platform, and a small limit block. The slope and the small limit block are located on both sides of the platform. The small limit block is vertically located on the side of the right-angled edge of the platform. The downward trend of the slope is towards a position away from the small limit block. A square annular groove is provided on the circumferential end plate of the cover plate, and a sealing strip is embedded in the square annular groove. The sealing strip abuts against the surrounding plate below. A square annular groove body with a shape opposite to that of the square annular groove is provided on the circumferential end of the surrounding plate, and the inner side edge of the square annular groove body abuts against the sealing strip. The arc-shaped baffle is adapted to the circumference of the surrounding plate, and the side is perpendicular to the surrounding plate. The number of the arc-shaped baffles is the same as that of the clips, and the arc-shaped baffles are arranged at intervals, that is, the interval between the arc-shaped baffles is the opening.

2. The rope cabin entrance and exit device according to claim 1, characterized in that: A sealing member is clamped and sleeved on the part of the main shaft passing through the cover plate. A bushing is sleeved on the part of the main shaft below the cover plate. The clips are evenly distributed on the bushing and are in interference fit with the bushing. The bushing is locked on the main shaft through fasteners, nuts, and washers.

3. The rope cabin access device according to claim 2, characterized in that: The clip is in a long rod shape. The end of the clip is located on the locking limit block and does not exceed the inner side surface of the square annular groove body. The clip is located at the position of the opening. The surrounding plate contacts the sealing strip, but the sealing strip is in an unloaded state.

4. The rope cabin access device according to claim 1, characterized in that: A square protrusion is provided above the part of the main shaft above the cover plate. A circular protrusion is provided at the bottom of the square protrusion. The size of the circular protrusion is larger than the size of the through groove of the cover plate and is just stuck at the upper part of the through groove. The square protrusion is sleeved with the sleeve at the bottom of the handle. The handle is in an inverted L shape.

5. The rope cabin access device according to claim 1, characterized in that: The wear-resistant bushing is in a barrel shape. The middle part of the wear-resistant bushing is in a cylindrical shape, and its diameter is adapted to the diameter of the annular baffle. The upper part of the cylindrical shape is a convex ring plate facing the outside. The bottom of the convex ring plate is clamped on the ship's deck above the surrounding plate.

6. The rope cabin entrance and exit device according to claim 1, characterized in that: An inwardly concave square groove is provided in the cover plate, and a lifting handle is provided in the square groove.

7. The usage method of a rope cabin access device according to claim 1, characterized in that, Including the following steps: Opening the hatch cover: Step 1: Sleeve the sleeve below the handle with the square protrusion above the main shaft; Step 2: Rotate the handle. The handle drives the main shaft, so that the three clips rotate. The three clips slide down along the slope of the locking limit block and reach the opening position of the annular baffle within the surrounding plate; Step 3: Lift the lifting handle upward and remove the cover plate. The hatch cover is opened; Step 4: Sleeve the wear-resistant bushing on the surrounding plate; Closing the hatch cover: S1: Remove the wear-resistant bushing from above the surrounding plate; S2: Use the lifting handle to place the cover plate above the surrounding plate. Align the sealing strip of the cover plate with the inner side plate of the square annular groove body of the surrounding plate; S3: Sleeve the sleeve below the handle with the square protrusion above the main shaft; S4: Rotate the handle. The handle drives the main shaft, so that the three clips rotate. The three clips climb along the slope of the trapezoidal locking limit block and reach the small limit block of the locking limit block for limiting. The hatch cover is locked.

Images