CN220563382U - Cover plate pressing mechanism and cabin top manhole sealing device - Google Patents

Abstract

The cover plate pressing mechanism comprises a pressing component and a locking component; the compression assembly comprises an electric push rod vertically arranged above the cover plate, a shell of the electric push rod is fixed on the cover plate through a bracket, a telescopic rod of the electric push rod is respectively hinged with a plurality of slide bar type lock tongues through a plurality of connecting rods, one end of the slide bar type lock tongue, which is far away from the connecting rods, is provided with a wedge-shaped head, and a guide rail for the slide bar type lock tongue to slide is arranged on the cover plate; the locking assembly comprises locking frames, the number of which is consistent with that of the slide bar type lock bolts, and locking channels for the slide bar type lock bolts to be inserted are formed in the locking frames. According to the utility model, the edge of the cover plate can be simultaneously pressed on the bin top manhole, so that the efficiency of pressing work is improved.

Description

A cover pressing mechanism and a silo roof manhole sealing device

Technical field

The utility model relates to the technical field of storage facility sealing, specifically a cover plate pressing mechanism and a warehouse roof manhole sealing device.

Background technique

As a type of storage and transfer warehouse, the shallow round warehouse has a lower comprehensive cost than ordinary silos and a higher degree of mechanization than room-type warehouses. It has the advantages of large storage capacity, small area and low operating costs. The roof of the shallow round silo is equipped with a passage for workers to enter and exit the warehouse for cutting samples and checking grain conditions - a manhole. At present, shallow round silos mostly use escalator-type manholes, that is, the manholes are larger in size. The rectangular hole is convenient for workers to carry items in and out of the warehouse, and is sealed by a sealing device to ensure the sealing performance of the shallow round warehouse.

In the prior art, the manhole extends upward to form an extension, and the sealing device is connected to the extension. The sealing device can cover the cover of the manhole. A rubber pad is often adhered to the bottom surface of the cover. When the cover is closed, At the opening, the rubber gasket is used to seal the manhole.

In practical applications, a compression unit is also installed between the manhole and the cover plate to improve the sealing effect of the manhole. As shown in Figure 10, the compression unit 8 includes a rotating member whose bottom end is rotationally connected to the top of the warehouse. The rotating member The top end of the manhole is bent toward the center of the manhole to form a bent portion. The bent portion is rotated and provided with a pressing rod that can press the cover plate to the upper port of the manhole. When in use, rotate the pressing rod to compress the cover plate. . However, in order to ensure the sealing effect, the compression units between the manhole and the cover are often arranged in multiple groups. When using such compression units to perform compression operations, it is necessary to twist the compression rods of the compression units one by one. , so the efficiency of the compaction work is limited.

Utility model content

The utility model aims to provide a cover plate pressing mechanism and a silo roof manhole sealing device, so as to simultaneously press the edges of the cover plate on the silo roof manhole and improve the efficiency of the pressing work.

In order to solve the above technical problems, the specific solution adopted by this utility model is: a cover plate pressing mechanism, the cover plate is used to cover the manhole on the warehouse roof, and an elastic spring is provided between the cover plate and the manhole on the warehouse roof. Seal, the cover pressing mechanism includes a pressing component and a locking component; the pressing component includes an electric push rod arranged vertically above the cover plate, the housing of the electric push rod is fixed on the cover plate through a bracket, and the electric push rod The telescopic rod of the push rod is respectively hinged with multiple sliding rod lock tongues through multiple connecting rods. The end of the sliding rod lock tongue away from the connecting rod is provided with a wedge-shaped head, and the cover plate is provided with a guide rail for the sliding rod lock tongue to slide. ; The locking assembly includes a locking frame with the same number as the sliding rod lock tongue. The locking frame is provided with a locking channel for the sliding rod lock tongue to be inserted.

As a further optimization of the above technical solution, the guide rail is provided with a limiting component capable of limiting the sliding range of the sliding rod lock tongue.

As a further optimization of the above technical solution, the limiting component includes a guide slot hole opened along the length direction of the guide rail, and the sliding rod lock tongue is provided with a limit block that can slide in the guide slot hole.

As a further optimization of the above technical solution, the limiting component includes a limiting bar arranged on the guide rail, and the sliding rod lock tongue is provided with limiting holes along its length direction.

A sealing device for a manhole at the top of a warehouse, which includes a cover opening and closing mechanism, a cover rotation mechanism and the above-mentioned cover pressing mechanism. The cover rotation mechanism includes a screw whose bottom end is rotatably connected to the outer wall of the manhole. The top of the screw A rotating handwheel is installed through the cover plate and can move up and down along the screw.

As a further optimization of the above technical solution, a spring is set on the rod body of the screw.

As a further optimization of the above technical solution, the cover opening and closing mechanism includes a rotating shaft fixed outside the manhole, a large strut connected to the rotating shaft, and a small strut connected to the end of the large strut. The end of the small strut is hinged on The upper surface of the cover.

As a further optimization of the above technical solution, the cover opening and closing mechanism includes a push rod hinged on the outside of the manhole.

As a further optimization of the above technical solution, the upper end surface of the manhole wall and the lower surface of the cover plate are provided with concave and convex sealing pairs.

As a further optimization of the above technical solution, the sealing pair includes an annular protrusion and an annular recess. The annular protrusion is provided on the upper end surface of the manhole wall, and the annular recess is provided on the lower surface of the cover plate. Alternatively, the annular protrusion is provided on the cover plate. On the lower surface of the plate, an annular depression is provided on the upper end surface of the manhole wall.

Compared with the existing technology, the beneficial effects of this utility model are as follows:

1. Through the cover plate pressing mechanism of the present utility model, after the cover plate is closed on the manhole, the telescopic rod pushes the connecting rod downward to move, and then the connecting rod pushes the sliding rod lock tongue on the upper plate of the cover plate. Slide on the surface, and the wedge-shaped head at the end of the sliding rod lock tongue is inserted into the locking frame, thereby pressing the cover plate against the manhole. Therefore, the utility model can simultaneously control the sliding of multiple sliding rod lock tongues below through the movement of a telescopic rod, and simultaneously compress the edges of the cover plate, thereby improving the efficiency of the compression work. At the same time, different sliding rods can The rod-type lock tongue is inserted into the locking frame at the same time, and is pressed at different angles at the same time. Compared with the prior art of pressing the pressing units one by one, on the one hand, uneven stress at different angles caused by pressing one by one can be avoided. , On the other hand, it can also avoid being pressed in one direction while lifting in the other direction, which will affect the sealing effect.

2. When the cover of the utility model is opened, the spring can push up the cover to form a gap between the rubber pad and the upper port of the manhole. Therefore, during the process of closing the cover, the rubber pad is close to one side of the cover rotation mechanism. The side will not be squeezed laterally, which prevents the rubber pad from falling off the cover plate and ensures the sealing effect of the utility model.

Description of drawings

Figure 1 is a schematic view of the front structure of the utility model;

Figure 2 is a schematic top view of the utility model;

Figure 3 is the A-A cross-sectional view of Figure 2 and the pressing diagram of the cover pressing mechanism;

Figure 4 shows the release diagram of the cover pressing mechanism;

Figure 5 is a schematic diagram of opening the manhole;

Figure 6 is a schematic diagram of the layout of each mechanism of the escalator manhole;

Figure 7 is a schematic structural diagram when the annular protrusion is provided on the upper end surface of the manhole side wall and the annular depression is provided on the lower surface of the cover plate;

Figure 8 is a schematic structural diagram when the annular recess is provided on the upper end surface of the manhole side wall and the annular protrusion is provided on the lower surface of the cover plate;

Figure 9 is a schematic structural diagram when the annular protrusion is arranged on the upper end surface of the manhole side wall and is located outside the side wall, and the annular depression is arranged on the lower surface of the cover plate;

Figure 10 is a schematic structural diagram of the pressing unit provided between the manhole and the cover plate in the prior art;

Reference signs: 1. Cover plate, 2. Cover opening and closing mechanism, 21. Rotating shaft, 22. Large support rod, 23. Small support rod, 24. Small support rod base, 3. Cover rotation mechanism, 31. Hinge Base, 32. Spring, 33. Screw, 34. Hinge upper fixed seat, 35. Rotating handwheel, 4. Cover pressing mechanism, 41. Electric push rod, 42. Connecting rod, 43. Coaxial hinge, 44 , sliding rod lock tongue, 45. guide slot hole, 46. limit block, 47. guide rail, 48. wedge-shaped head, 49. locking frame, 410. limit strip, 411. limit hole, 5. entry Hole, 6. Elastic seal, 7. Sealing pair, 71. Annular protrusion, 72. Annular depression, 8. Pressing unit.

Detailed ways

The technical solutions of the present utility model will be further elaborated in detail below in conjunction with the accompanying drawings and specific embodiments. The parts of the utility model that are not described in detail and disclosed in the following embodiments should be understood to be those known or should be known by those skilled in the art. There is technology.

As shown in Figure 1, the utility model discloses a cover plate pressing mechanism. The cover plate 1 is used to cover the manhole 5 on the warehouse roof. An elastic spring is provided between the cover plate 1 and the manhole 5 on the warehouse roof. Seal 6, the elastic seal is a sealing rubber pad and is bonded to the lower surface of the cover plate 1. In addition, the elastic seal 6 can also be replaced with a sealing strip. The sealing strip is circumferentially arranged along the lower surface of the cover plate 1 and corresponds to the upper end surface of the hole wall of the warehouse top manhole 5. When the cover plate 1 is closed, When closing the silo top manhole 5, the cover plate 1 and the silo top manhole 5 are sealed with a sealing strip.

The cover pressing mechanism 4 includes a pressing component and a locking component. The pressing assembly includes an electric push rod 41 arranged above the cover plate 1. The housing of the electric push rod 41 is fixed on the cover plate 1 through a bracket (not shown in the figure). The telescopic rod of the electric push rod 41 is vertically downward. And the end of the telescopic rod is hinged with a plurality of connecting rods 42, the upper ends of the connecting rods 42 are hinged at the end of the telescopic rod, and the lower ends of the connecting rods 42 face different directions. A sliding rod lock tongue 44 is hingedly connected to the end of the connecting rod 42 away from the telescopic rod. The sliding rod lock tongue 44 is integrally provided with a wedge-shaped head 48 at an end away from the connecting rod 42 . The longitudinal section of the wedge-shaped head 48 is triangular. The lower end surface of the wedge-shaped head 48 is flush with the lower end surface of the sliding rod lock tongue 44 , and the upper end surface gradually decreases along the direction in which the sliding rod lock tongue 44 is away from the connecting rod 42 .

Specifically, as shown in Figures 1 and 2, the manhole 5 in the warehouse roof in this embodiment is a square hole, so the cover 1 used in conjunction with the manhole 5 is also square, and the electric push rod 41 is provided on the cover. At the center of 1, there are four connecting rods 42 hinged below the electric push rod 41, facing the four sides of the square cover 1 respectively. One end of the connecting rod 42 away from the telescopic rod is connected to the sliding rod lock tongue 44 through a coaxial hinge 43. The four sliding rod lock tongues 44 are perpendicular to each other, and the four sliding rod lock tongues 44 are respectively connected with the square cover plate 1. The four sides are vertical. The coaxial hinge 43 is a rotation axis. The end of the connecting rod 42 away from the telescopic rod is provided with a protruding strip extending along the length direction of the connecting rod 42 . The sliding rod lock tongue 44 is provided with a protruding strip at one end facing the connecting rod 42 . After the protruding strip is inserted into the groove, the groove and the protruding strip are inserted into the groove and the protruding strip in sequence through the rotating shaft, thereby realizing the coaxial hinge of the connecting rod 42 and the sliding rod lock tongue 44. The rotating shaft is vertical. The connecting rod 42 is arranged in the length direction and the rotation axis is parallel to the surface of the cover plate 1 .

When the manhole is an escalator-type manhole, as shown in Figure 6, since the escalator-type manhole is rectangular, in order to effectively seal the periphery of the rectangular cover plate 1, two holes are provided on the upper surface of the cover plate 1. Each cover plate pressing mechanism 4 is connected with three sliding rod lock tongues 44 . Each cover plate pressing mechanism 4 keeps one of the sliding rod lock tongues 44 facing the short side of the rectangular cover plate 1, and the other two sliding rod lock tongues 44 facing the long sides of both sides respectively, so that the rectangular cover plate Each long side of 1 is provided with two sliding rod lock tongues 44 correspondingly, and the short side is correspondingly provided with one sliding rod lock tongue 44 to ensure uniform stress around the cover plate 1 .

The locking assembly includes a locking frame 49 with the same number as the sliding rod lock tongue 44. The locking frame 49 is provided with a locking channel for the sliding rod lock tongue 44 to be inserted. The locking frame 49 is in the shape of a triangle and includes two vertical bars and a horizontal bar located at the upper end of the vertical bars and connected between the two vertical bars. The vertical bars and the horizontal bars form the locking channel, and the locking channel The height of the wedge-shaped head 48 is lower than the highest position of the wedge-shaped head 48, so that during the pressing process of the cover plate 1, as the wedge-shaped head 48 is inserted into the locking channel, the locking channel squeezes the wedge-shaped head 48, and the wedge-shaped head 48 drives the cover plate 1 Move down and squeeze the elastic seal 6 to finally seal the manhole 5 with the elastic seal 6 .

The two vertical rods of the locking frame 49 are fixed on the outside of the hole wall of the manhole 5. In this embodiment, the lower end of the vertical rod is provided with a bent portion extending toward the outside of the manhole 5, so that the vertical rods are in contact with the manhole 5. A certain gap is left between the walls of the holes 5 to prevent the vertical rods from interfering with the closing process of the cover plate 1.

In addition, the locking bracket 49 can also be fixed on the wall outside the manhole 5. It only needs to be ensured that the locking channel in the locking bracket 49 faces the wedge head 48 so that the wedge head 48 can be inserted, and the height of the locking channel is low. At the highest position of the wedge-shaped head 48.

The cover plate 1 is provided with a guide rail 47 for the sliding rod lock tongue 44 to slide. The guide rail 47 is provided with a limiting component capable of limiting the sliding range of the slide rod lock tongue 44 . As shown in FIG. 1 , the limiting assembly includes a guide slot 45 opened along the length direction of the guide rail 47 . The sliding rod lock tongue 44 is provided with a limit block 46 that can slide in the guide slot 45 .

The guide rail 47 is an installation frame arranged on the cover plate 1. The installation frame is elongated. A sliding channel is provided in the installation frame for the sliding rod lock tongue 4 to extend into. The direction of the sliding channel is consistent with the length direction of the installation frame. The guide slot 45 is opened on the side wall of the sliding channel. The guide slot 45 limits the sliding range of the sliding rod lock tongue 44, thereby controlling the depth of the wedge head 48 extending into the locking frame 49 to control the sealing of the cover plate 1. degree.

As another arrangement method of the limiting component, as shown in FIG. 3 , the limiting component includes a limiting bar 410 provided on the guide rail 47 , and a limiting hole 411 is formed on the sliding rod lock tongue 44 along its length direction. During the sliding process of the sliding rod lock tongue 44, the limiting hole 411 moves with the sliding of the sliding rod lock tongue 44, and the sliding range of the sliding rod lock tongue 44 can be limited by the limit strip 410 fixed on the guide rail 47. .

3 is a schematic structural diagram of the wedge head 48 inserted into the locking frame 49 (that is, when the cover pressing mechanism 4 is pressed). At this time, the limit bar 410 is in contact with the hole at the end of the limit hole 411 away from the wedge head 48 As shown in FIG. 4 , it is a schematic structural diagram after the wedge head 48 is separated from the locking frame 49 (that is, when the cover pressing mechanism 4 is released). At this time, the limit bar 410 is in contact with the limit hole 411 and is close to the wedge head 48 The hole wall at one end.

In the present utility model, the electric push rod 41 of the cover pressing mechanism 4 is operated to drive the telescopic rod on it to move up and down, thereby controlling the sliding of the plurality of sliding rod lock tongues 44 below, thereby realizing or releasing the lock tongue. The edge of the cover plate 1 is pressed simultaneously, which improves the efficiency of the pressing work and has a high degree of automation.

Continuing to refer to Figures 1 and 2, the utility model also discloses a silo roof manhole sealing device, which includes a cover opening and closing mechanism 2, a cover rotating mechanism 3 and the above-mentioned cover pressing mechanism 4.

The cover opening and closing mechanism 2 and the cover rotating mechanism 3 are arranged on the same side of the manhole 5. The cover opening and closing mechanism 2 includes a rotating shaft 21 fixed outside the manhole 5 and a large support rod 22 connected to the rotating shaft 21. and a small strut 23 connected to the end of the large strut 22. The rotating shaft 21 is laterally fixed on the wall on one side of the manhole 5. The rotating shaft 21 is connected with a driving motor for driving its rotation. There are two large struts 22 and two small struts 23. The two large struts 22 are distributed in parallel. And fixed on both ends of the rotating shaft 21, each small support rod 23 is coaxially hinged with the corresponding large support rod 22. The specific hinge method can refer to the connection method between the connecting rod 42 and the sliding rod lock tongue 44, which will not be discussed here. Again. The upper surface of the cover 1 is provided with a small support base 24, and the end of the small support 23 is hinged on the upper surface of the cover 1. Figure 5 shows a schematic diagram after the manhole 5 is opened. When the manhole 5 is opened, the driving motor drives the rotating shaft 21 to rotate, and the large support rod 22 can be driven to rotate through the rotating shaft 21. The rotation of the large support rod 22 can pull the small The support rod 23 moves in the direction of the rotating shaft 21, thereby driving the cover plate 1 to flip around the cover plate rotating mechanism 3, opening the manhole 5; rotating the rotating shaft 21 in the opposite direction can close the manhole 5.

Setting two large struts 22 and two small struts 23 respectively can ensure the stability of the cover 1 when it is opened or closed. Depending on the specific size of the cover 1, the large strut 22 and the small strut 23 can also be Set to multiple roots of more than two respectively.

As another arrangement method of the cover opening and closing mechanism 2, the cover opening and closing mechanism 2 includes a push rod (not shown in the figure) hinged outside the manhole 5. The number of push rods is two and the two push rods are The rods are parallel. The push rod is an electric push rod. The shell of the electric push rod is hinged on the wall on the side of the manhole 5. The end of the telescopic rod of the electric push rod is hinged on the upper surface of the cover plate 1. It is pulled by the contraction of the electric push rod. The cover 1 opens the manhole 5, and the cover 1 is closed on the manhole 5 through the extension of the electric push rod.

The cover opening and closing mechanism 2 of this embodiment can realize automatic and slow opening and closing of the cover 1. Compared with the method of manually pulling the cover 1, it reduces the operator's workload and is more practical.

As shown in Figures 1 and 7, the cover rotating mechanism 3 includes a screw 33 whose bottom end is rotatably connected to the outer wall of the manhole 5. The top of the screw 33 passes through the cover 1 and is equipped with a rotating handwheel that can move up and down along the screw 33. 35. A hinge base 31 is fixedly provided on the outer wall of the manhole 5. The hinge base 31 includes two fixed blocks arranged at intervals. A rotation axis with an axis perpendicular to the axis of the screw 33 is fixedly connected between the two fixed blocks. The bottom of the screw 33 is connected to the axis of the screw 33. The rotating shaft is rotatably connected, and during the opening process of the cover 1, the screw 33 can rotate around the axis of the rotating shaft. The cover plate 1 is fixedly connected with an upper hinge fixing seat 34 corresponding to the hinge base 31 . The upper hinge fixing seat 34 is a fixed plate. The upper hinge fixing seat 34 is provided with a perforation through which the screw rod 33 can pass. The hinge upper fixed seat 34 extends in a direction away from the cover plate 1. The connection between the hinge upper fixed seat 34 and the cover plate 1 can be bolted connection, integral connection or welding. In this embodiment, the connection mode of the two is integral connection; The diameter of the hole is larger than the diameter of the screw rod 33 and is coaxial with the screw rod 33, so that the screw rod 33 can pass through the hole.

The rotating handwheel 35 is located above the fixed seat 34 on the hinge. The outer diameter of the rotating handwheel 35 is larger than the diameter of the hole, and the inner diameter is the same as the diameter of the screw 33. The inner wall of the rotating handwheel 35 is provided with internal threads that match the screw 33.

A spring 32 is mounted on the rod body of the screw rod 33. In this embodiment, the spring 32 is located between the fixed seat 34 on the hinge and the hinge base 31. When the cover plate 1 is pressed against the manhole 5, turn the rotating handwheel 35 to move it downward, and then push the hinge upper fixed seat 34 and the cover plate 1 to move toward the manhole 5 until the corresponding cover plate 1 is pressed. Tighten to the upper end of the side wall of the manhole 5. At this time, the spring 32 is in a compressed state; during the opening process of the cover 1, rotate the handwheel 35 in the opposite direction to move it upward, and the spring 32 pushes the cover under the action of its restoring elasticity. 1. Move away from the manhole 5 until a gap is formed between the elastic seal 6 and the upper end surface of the side wall of the manhole 5. Then lift the side of the cover 1 away from the cover rotation mechanism 3 and flip it upward to open. When the cover 1 is closed again, the side wall of the manhole 5 located close to the cover rotating mechanism 3 will not squeeze the elastic seal 6 laterally. At the same time, when the cover 1 is closed again, the side wall of the manhole 5 located close to the cover rotating mechanism 3 The side walls of the hole 5 will not squeeze the elastic seal 6 laterally, thereby preventing the elastic seal 6 from falling off the cover plate 1 and causing the sealing property to gradually deteriorate. Especially when the elastic seal 6 provided on the lower surface of the cover plate 1 is a sealing strip, due to the limited width of the sealing strip, it is more likely to be squeezed by the side wall of the manhole 5 and fall off. The arrangement of the spring 32 on the screw 33 It is more helpful to ensure the sealing performance when the cover plate 1 is provided with a sealing strip.

In order to further enhance the orifice sealing effect of the manhole 5, a concave-convex seal pair 7 is provided on the upper end surface of the wall of the manhole 5 and the lower surface of the cover plate 1.

The sealing pair 7 includes an annular protrusion 71 and an annular recess 72. As shown in Figure 7, the annular protrusion 71 is provided on the upper end surface of the wall of the manhole 5 and is located in the middle of the upper end surface. The annular recess 72 is provided under the cover plate 1. The plate surface; as shown in Figure 8, the annular protrusion 71 is provided on the lower surface of the cover plate 1, and the annular recess 72 is provided on the upper end surface of the wall of the manhole 5; as shown in Figure 9, the annular protrusion 71 is provided on the lower surface of the manhole 5. The upper end surface of the wall of the manhole 5 is located at the edge of the upper end surface, and an annular depression 72 is provided on the lower surface of the cover plate 1 . Therefore, the annular protrusion 71 and the annular recess 72 can be arranged in various positions, as long as they ensure concave-convex matching. Through the combined use of the annular protrusion 71 and the annular recess 72, the sealing strip or the elastic seal 6 is arranged between the annular protrusion 71 and the annular recess 72, thereby enhancing the firmness of the sealing strip and the rubber pad to a certain extent. It also increases the resistance to air flow inside and outside the hole, improving the sealing effect.

The above descriptions are only preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present utility model shall be included in within the protection scope of this utility model.

Claims (10)

1. A cover plate pressing mechanism. The cover plate (1) is used to cover the manhole (5) on the warehouse roof. An elastic seal is provided between the cover plate (1) and the manhole (5) on the warehouse roof. Part (6), characterized in that: the cover plate pressing mechanism (4) includes a pressing component and a locking component; The pressing assembly includes an electric push rod (41) arranged vertically above the cover plate (1). The housing of the electric push rod (41) is fixed on the cover plate (1) through a bracket. The telescopic push rod (41) The rod is hinged with multiple sliding rod lock tongues (44) respectively through multiple connecting rods (42). One end of the sliding rod lock tongue (44) away from the connecting rod (42) is provided with a wedge-shaped head (48), and the cover plate (48) 1) There is a guide rail (47) for the sliding rod lock tongue (44) to slide; The locking assembly includes a locking frame (49) with the same number as the sliding rod lock tongue (44). The locking frame (49) is provided with a locking channel for the sliding rod lock tongue (44) to be inserted. 2. A cover pressing mechanism according to claim 1, characterized in that: the guide rail (47) is provided with a limiting component capable of limiting the sliding range of the sliding rod lock tongue (44). 3. A cover pressing mechanism according to claim 2, characterized in that: the limiting component includes a guide slot (45) opened along the length direction of the guide rail (47), and the sliding rod lock tongue (44) A limiting block (46) that can slide in the guide slot hole (45) is provided. 4. A cover pressing mechanism according to claim 2, characterized in that: the limiting component includes a limiting bar (410) arranged on the guide rail (47), and the upper edge of the sliding rod lock tongue (44) A limited hole (411) is provided in its length direction. 5. A sealing device for a warehouse roof manhole, characterized by: comprising a cover opening and closing mechanism (2), a cover rotating mechanism (3) and a cover pressing mechanism (4) as claimed in claim 1, The cover rotating mechanism (3) includes a screw (33) whose bottom end is rotationally connected to the outer wall of the manhole (5). The top of the screw (33) passes through the cover (1) and is installed with a screw (33) that can move up and down along the screw (33). of the rotating handwheel (35). 6. A sealing device for a warehouse roof manhole according to claim 5, characterized in that a spring (32) is set on the rod body of the screw (33). 7. A silo top manhole sealing device according to claim 5, characterized in that: the cover opening and closing mechanism (2) includes a rotating shaft (21) fixed outside the manhole (5), and a rotating shaft connected to the manhole. The large support rod (22) on (21) and the small support rod (23) connected to the end of the large support rod (22), the end of the small support rod (23) is hinged on the upper surface of the cover plate (1). 8. A sealing device for a warehouse roof manhole according to claim 5, characterized in that: the cover opening and closing mechanism (2) includes a push rod hinged on the outside of the manhole (5). 9. A silo roof manhole sealing device according to claim 5, characterized in that: the upper end surface of the hole wall of the manhole (5) and the lower surface of the cover plate (1) are provided with concave and convex matching sealing pairs. (7). 10. A silo roof manhole sealing device according to claim 9, characterized in that: the sealing pair (7) includes an annular protrusion (71) and an annular depression (72), and the annular protrusion (71) is arranged on On the upper end surface of the hole wall of the manhole (5), an annular recess (72) is provided on the lower surface of the cover plate (1), or an annular protrusion (71) is provided on the lower surface of the cover plate (1), and an annular recess (72) is provided on the lower surface of the cover plate (1). 72) is arranged on the upper end surface of the hole wall of the manhole (5).