Power distribution bolt device with multi-stage locking mechanism

Abstract

The invention relates to the technical field of bolt devices, in particular to a power distribution bolt device with a multi-stage locking mechanism, which comprises a central bolt and an outer sleeve column, the central bolt is inserted into the outer sleeve column, a threaded column at the bottom of the central bolt is connected with the inner wall of the outer sleeve column through internal and external threads in a matched manner, and the interior of the central bolt is of a hollow structure. And an adjustable stopper mechanism is arranged in the center bolt. According to the power distribution bolt device with the multi-stage locking mechanism, due to the fact that the adjustable blocking piece mechanism is arranged, even if the operation faces of the device do not have the same space, the bolt device can be fixedly installed, and operation is more convenient; due to the fact that the locking mechanism is arranged, when the bolt device is installed, the structure is not prone to loosening and rotating, and using is safer and more stable.

Description

Technical Field

[0001] The present invention relates to the technical field of bolt devices, and particularly to a bolt device for power distribution and transmission with a multi-stage locking mechanism. Background Technique

[0002] The power distribution and transmission project is an important branch of the power system project, which mainly focuses on safely, reliably and economically transporting and distributing electric power from the end of the power transmission system (usually a regional substation or switch station) to the final users (such as households, commercial and industrial users). In the power distribution and transmission project, devices such as transformers, switchgear, protection devices, transmission equipment, electric poles, and iron towers are required, and a large number of bolt devices are needed in these devices. Traditional bolts are used for connecting two or more objects, and are mostly used in combination with nuts. As Figure 1 shown, for example: when connecting two objects A and B, first stack A and B together, place the nut on the A surface, pass the stud through BA from the B surface, and then use tools such as hands or wrenches to fix the nut, and then turn the stud to complete the installation; however, in the power distribution and transmission project, there are some usage situations that make the bolt device very troublesome to use: when the AB surfaces do not belong to the same space, such as installing an object on the cabinet wall inside or outside the power distribution cabinet, if the operator turns the bolt inside, the nut outside cannot be fixed, and when turning, the two will rotate synchronously, and the bolt cannot be installed stably, and multiple operators need to cooperate; there is also in some installation sites (such as beside the railway), there will be large vibrations, which are likely to cause the bolt device to loosen and rotate, so improvements are needed. Summary of the Invention

[0003] The purpose of the present invention is to provide a bolt device for power distribution and transmission with a multi-stage locking mechanism to solve the problems proposed in the above background technique.

[0004] To achieve the above purpose, the present invention provides the following technical solution: A bolt device for power distribution and transmission with a multi-stage locking mechanism, including a central bolt and an outer sleeve column. The central bolt is inserted into the outer sleeve column. The threaded column at the bottom of the central bolt is connected to the inner wall of the outer sleeve column through internal and external thread cooperation. The inside of the central bolt is a hollow structure, and an adjustable stopper mechanism is arranged inside the central bolt; An installation groove is provided at the upper end of the outer sleeve column, and a rotating ring is rotatably installed in the installation groove. A locking mechanism is arranged on the rotating ring, and the locking mechanism is used to lock the outer sleeve column and the stopper mechanism inside the outer sleeve column.

[0005] Preferably, anti-slip grooves are provided on the side wall of the outer sleeve column.

[0006] Preferably, a buffer pad ring is connected to the bottom of the outer sleeve column, and the buffer pad ring is used for buffering and anti-slip.

[0007] Preferably, the blocking member mechanism includes several movable stoppers. At the bottom end of the threaded column portion of the central bolt, several bottom side grooves are provided, and one movable stopper is arranged in each bottom side groove. A groove is provided at one end of the movable stopper located inside the central bolt, a connecting shaft is arranged in the groove, a traction belt is fixed on the connecting shaft, and the end of the traction belt is connected to a top plate; The blocking member mechanism further includes a driving component arranged inside the central bolt. The driving component is used to adjust the position state of the movable stopper. The driving component includes an inner core. A groove for cooperating with an internal hexagonal wrench is provided at the top of the inner core. Such a groove is also provided at the screw head portion of the central bolt. A round hole is provided at the center of this groove, and the inner core is inserted into the round hole. Two internal hexagonal wrenches with different sizes can be used to turn the central bolt and the inner core respectively. The diameter of the lower section of the inner core is larger than that of the upper section. Threads are provided on the side wall of the lower section of the inner core. The lower section of the inner core is connected to the inner side wall of the central bolt through internal and external thread cooperation. A push rod is connected to the bottom of the inner core. The push rod corresponds to the top plate. By turning the inner core to make it descend, the push rod descends and pushes the top plate downward. The movable stopper can be pulled by the traction belt to change from a vertical state to a horizontal state. A limiting support ring is arranged on the side wall at the bottom end of the central bolt, and the limiting support ring is used to limit the movable stopper.

[0008] Preferably, the movable stopper is rotatably installed in the bottom side groove through a rotating shaft on the side wall. When the device is not in use, the movable stopper is in a vertical state. A torsion spring connection can be provided at the connection between the rotating shaft and the inner wall of the bottom side groove, so that the movable stopper can automatically adjust to a vertical state and retract into the threaded column of the central bolt without manual adjustment.

[0009] Preferably, an anti-slip pad is provided on the upper surface of the end of the movable stopper.

[0010] Preferably, the traction belt is a flexible high-strength traction wire. The diameter of the traction belt is 1-2 mm. The traction belt is made of one of aramid fiber, ultra-high molecular weight polyethylene fiber, and multi-strand braided fine metal wire rope, and needs to have a certain flexibility and high strength.

[0011] Preferably, several positioning holes are provided on the bottom surface of the installation groove. A positioning plug is movably inserted on the rotating ring, and the positioning plug is correspondingly inserted into the positioning holes. The bottom of the positioning plug is a permanent magnet, and the bottom of the positioning plug is adsorbed inside the positioning holes.

[0012] Preferably, the locking mechanism includes a locking assembly mounted on a rotating ring, a cavity is provided in the rotating ring, the locking assembly includes a locking pin that movably passes through the cavity, a pull block is provided at the outer end of the locking pin, the pull block is used for the user to dial, an inner movable plate is provided on the portion of the locking pin located in the cavity, a group of tightening springs are connected to the side wall of the inner movable plate, a fixing hole is provided on the side wall of the connection between the threaded column and the screw head of the central bolt, the inner end of the locking pin corresponds to the fixing hole, and when the device is installed, the rotating ring is first rotated so that the locking pin and the fixing The fixed holes are aligned, and the tightening spring pushes the inner movable plate so that the inner end of the locking pin is inserted into the fixing hole. Then the positioning pin is inserted into the positioning hole at the corresponding position to fix the rotating ring. The operation steps are not unique. You can also insert the positioning pin into the positioning hole to fix the rotating ring first, and then rotate and install the center bolt and outer sleeve column. If there is a slight gap between the locking pin and the fixing hole and they are not aligned, because the buffer washer has a buffering function, you can make a slight adjustment to align them after the installation is completed. At the same time, the center bolt and outer sleeve column are relatively fixed and will not loosen at will.

[0013] Preferably, a circle of clamping grooves is provided on the upper side wall of the inner core, and an inner mounting ring is embedded and installed on the inner side wall at the connection between the threaded column and the screw head of the center bolt, and several annular inflatable air bags are arranged on the inner wall of the inner mounting ring, and an inner clamping plate is connected to the air bags, and the inner clamping plate is embedded and installed on the inner wall of the inner mounting ring. The inner clamping plate can only move inwards and outwards relative to the inner mounting ring and cannot move left and right. A card ridge is provided on the inner side wall of the inner clamping plate, and the card ridge and the clamping groove correspond to each other. An air bag boss is connected on the outer wall of the inner mounting ring, and the air bag boss is located in the fixing hole. When the locking pin is inserted into the fixing hole, the air bag boss is compressed, so that the air bag on the inner mounting ring expands and pushes the inner clamping plate to move. The card ridge is originally attached to the side wall of the inner core, so the moving distance is very small, and the card ridge on the inner clamping plate is embedded in the clamping groove, which can fix the inner core to prevent rotation and loosening after the device is installed.

[0014] Preferably, the diameter of the airbag boss is larger than the inner diameter of the fixing hole opening, so that when one airbag boss is compressed, if there are multiple airbag bosses, the remaining airbag bosses 17 will not expand and stretch, and only the airbag on the inner mounting ring can expand.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention proposes a bolt device for power distribution with a multi-stage locking mechanism. Since an adjustable blocking mechanism is provided, the bolt device can be fixedly installed even when the operating surface of the device does not exist in the same space, and the operation is more convenient. And since a locking mechanism is provided, when the bolt device is installed, its structure will not loosen and rotate easily, and it is safer and more stable to use.

[0016] 2. When actually operating to connect A and B, pass the bottom end of the central bolt through the mounting holes on A and B, then turn the inner core to make it descend, and further the ejector rod descends to push down the top plate. The movable stop block can be pulled by the traction belt to change from the vertical state to the horizontal state. At this time, the movable stop block and the outer sleeve column are respectively located on the two sides of A and B. Then rotate the central bolt or the outer sleeve column, and the outer sleeve column and the movable stop block are respectively pressed on the surfaces of A and B, so that the bolt can be installed in the same operating space.

[0017] 3. After the installation is completed, first rotate the rotating ring to align the locking plug column with the fixing hole. The top spring pushes the inner movable plate so that the inner end of the locking plug column is inserted into the fixing hole. Then insert the positioning plug into the positioning hole at the corresponding position to fix the rotating ring. At the same time, the central bolt and the outer sleeve column are also relatively fixed and will not loosen randomly. When the locking plug column is inserted into the fixing hole, the airbag convex column is compressed so that the airbag on the inner mounting ring expands to push the inner clamping plate to move, and the card ribs on the inner clamping plate are embedded in the clamping groove, which can fix the inner core to prevent rotational loosening after the device is installed. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of a bolt device in the prior art.

[0019] Figure 2 It is a schematic structural diagram of the bolt device of the present invention.

[0020] Figure 3 It is a structural diagram of another perspective of the bolt device of the present invention.

[0021] Figure 4 It is a schematic structural diagram of the central bolt of the present invention.

[0022] Figure 5 It is a schematic structural diagram of the outer sleeve column of the present invention.

[0023] Figure 6 It is a schematic structural diagram of the inner core connection structure of the present invention.

[0024] Figure 7 It is a schematic structural diagram of the movable stop block connection structure of the present invention.

[0025] Figure 8 It is a schematic structural diagram of the locking assembly of the present invention.

[0026] Figure 9 It is a schematic structural diagram of the connection structure at the top end of the inner core of the present invention.

[0027] Figure 10 For the present invention Figure 9 Another embodiment of the structure in the schematic diagram.

[0028] In the figure: central bolt 1, outer sleeve column 2, buffer cushion ring 201, bottom side groove 3, movable stopper 4, connecting shaft 5, traction belt 6, top plate 7, inner core 8, ejector rod 9, limit support ring 10, rotating ring 11, positioning hole 12, positioning plug 13, locking assembly 14, locking plug 1401, pull block 1402, inner movable plate 1403, top spring 1404, fixing hole 15, inner mounting ring 16, airbag convex column 17, inner clamping plate 18, clamping groove 19. Detailed implementation manner

[0029] 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. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0030] Please refer to Figures 1 to 10 , the present invention provides a technical solution: a distribution and power supply bolt device with a multi-stage locking mechanism, including a central bolt 1 and an outer sleeve column 2. Anti-slip grooves are provided on the side wall of the outer sleeve column 2 to facilitate clamping and fixing. A buffer cushion ring 201 is connected to the bottom of the outer sleeve column 2. The buffer cushion ring 201 is used for buffering and anti-slip. The central bolt 1 is inserted into the outer sleeve column 2, and the threaded column at the bottom of the central bolt 1 is connected to the inner wall of the outer sleeve column 2 through internal and external thread cooperation.

[0031] The central bolt 1 has a hollow structure inside, and an adjustable stopper mechanism is provided inside the central bolt 1. The stopper mechanism includes several movable stoppers 4. Several bottom side grooves 3 are provided at the bottom end of the threaded column part of the central bolt 1. One movable stopper 4 is provided in each bottom side groove 3. Anti-slip pads are provided on the upper surface of the end of the movable stopper 4. The movable stopper 4 is rotatably installed in the bottom side groove 3 through a rotating shaft on the side wall. When the device is not in use, the movable stopper 4 is in a vertical state. A torsion spring connection can be provided at the connection between the rotating shaft and the inner wall of the bottom side groove 3 to facilitate the movable stopper 4 to automatically adjust to the vertical state and retract into the threaded column of the central bolt 1 without manual adjustment.

[0032] A groove is provided at one end of the movable stopper 4 located inside the central bolt 1. A connecting shaft 5 is arranged in the groove. A traction belt 6 is fixed on the connecting shaft 5. The traction belt 6 is a flexible high-strength traction wire. The diameter of the traction belt 6 is 1-2 mm, which can also be set according to requirements. The traction belt 6 is made of one of aramid fiber, ultra-high molecular weight polyethylene fiber, and multi-strand braided fine metal wire rope, and needs to have a certain flexibility and high strength. The end of the traction belt 6 is connected to a top plate 7. The stopper mechanism further includes a driving component arranged inside the central bolt 1. The driving component is used to adjust the position state of the movable stopper 4. The driving component includes an inner core 8. A groove for cooperating with an inner hexagon wrench is provided at the top of the inner core 8. Such a groove is also provided at the screw head of the central bolt 1. A round hole is provided at the center of this groove, and the inner core 8 is inserted into the round hole. Two inner hexagon wrenches with different model sizes can be used to turn the central bolt 1 and the inner core 8 respectively. The diameter of the lower section of the inner core 8 is larger than that of the upper section. Threads are provided on the side wall of the lower section of the inner core 8. The lower section of the inner core 8 and the inner side wall of the central bolt 1 are connected by internal and external thread cooperation. A push rod 9 is connected to the bottom of the inner core 8. The push rod 9 corresponds to the top plate 7. By rotating the inner core 8 to make it descend, the push rod 9 descends to push down the top plate 7. The movable stopper 4 can be pulled by the traction belt 6 to change from a vertical state to a horizontal state. A limiting support ring 10 is provided on the side wall of the bottom end of the central bolt 1. The limiting support ring 10 is used to limit the movable stopper 4.

[0033] An installation groove is provided at the upper end of the outer sleeve column 2. A rotating ring 11 is rotatably installed in the installation groove. A plurality of positioning holes 12 are formed on the bottom surface of the installation groove. A positioning plug 13 is movably inserted into the rotating ring 11. The positioning plug 13 is correspondingly inserted into the positioning hole 12. The bottom of the positioning plug 13 is a permanent magnet, and the bottom of the positioning plug 13 is adsorbed inside the positioning hole 12. A locking mechanism is provided on the rotating ring 11, and the locking mechanism is used to lock the outer sleeve column 2 and the blocking member mechanism inside the outer sleeve column 2. The locking mechanism includes a locking assembly 14 installed on the rotating ring 11. A cavity is provided inside the rotating ring 11. The locking assembly 14 includes a locking plug 1401 that movably penetrates the cavity. A pulling block 1402 is provided at the outer end of the locking plug 1401, and the pulling block 1402 is used for the user to toggle. An inner movable plate 1403 is provided on the part of the locking plug 1401 located in the cavity. A set of tightening springs 1404 are connected to the side wall of the inner movable plate 1403. A fixing hole 15 is formed on the side wall at the connection of the threaded column and the screw head of the central bolt 1. The inner end of the locking plug 1401 corresponds to the fixing hole 15. After the device is installed, first rotate the rotating ring 11 to align the locking plug 1401 with the fixing hole 15. The tightening spring 1404 pushes the inner movable plate 1403 to insert the inner end of the locking plug 1401 into the fixing hole 15. Then insert the positioning plug 13 into the positioning hole 12 at the corresponding position, and the rotating ring 11 can be fixed. The operation steps are not unique. It is also possible to first insert the positioning plug 13 into the positioning hole 12 to fix the rotating ring 11, and then perform the rotational installation of the central bolt 1 and the outer sleeve column 2. If there is a slight gap between the locking plug 1401 and the fixing hole 15 and they are not aligned, because the buffer pad ring 201 has a buffering function, it can be slightly adjusted to align after the installation is completed. At the same time, the central bolt 1 and the outer sleeve column 2 are also relatively fixed and will not loosen randomly.

[0034] A clamping groove 19 is provided in a circle on the upper side wall of the inner core 8. An inner mounting ring 16 is embedded and installed on the inner side wall at the connection of the threaded column and the screw head of the central bolt 1. Several annular inflatable airbags are arranged on the inner wall of the inner mounting ring 16. An inner clamping plate 18 is connected to the airbag. The inner clamping plate 18 is embedded and installed on the inner wall of the inner mounting ring 16. The inner clamping plate 18 can only move in and out relative to the inner mounting ring 16 and cannot move left and right. Corrugations are provided on the inner side wall of the inner clamping plate 18. When the movable stop block 4 is unfolded to a horizontal state, the position height of the corrugations corresponds to that of the clamping groove 19, and the length of the clamping groove 19 can be set longer to ensure the correspondence. An airbag convex column 17 is connected to the outer wall of the inner mounting ring 16. The airbag convex column 17 is located in the fixing hole 15. When the locking plug 1401 is inserted into the fixing hole 15, the airbag convex column 17 is compressed, so that the airbag on the inner mounting ring 16 expands and pushes the inner clamping plate 18 to move. The corrugations originally fit on the side wall of the inner core 8, so the moving distance is very small. The corrugations on the inner clamping plate 18 are embedded in the clamping groove 19, and the inner core 8 can be fixed to prevent rotation and loosening after the device is installed. If the corrugations on the inner clamping plate 18 pushed by the expansion of the airbag do not align with the clamping groove 19, in this case, if the inner core 8 is not loose, it does not affect the use of the device. If the inner core 8 rotates and loosens, when the inner core 8 rotates to align the clamping groove 19 with the corrugations, due to the air pressure inside the airbag, the corrugations will automatically be embedded in the clamping groove 19. At this time, the rotation angle of the inner core 8 is very small and still does not affect the use of the device.

[0035] In some embodiments, multiple airbag convex columns 17 and fixing holes 15 can be provided to facilitate alignment with the locking plug 1401. The diameter of the airbag convex column 17 is larger than the inner diameter of the opening of the fixing hole 15, so that when one airbag convex column 17 is compressed, if there are multiple airbag convex columns 17, the remaining airbag convex columns 17 will not expand and elongate, and only the airbag on the inner mounting ring 16 can expand.

[0036] When actually operating to connect A and B, pass the bottom end of the central bolt 1 through the mounting holes on A and B, then turn the inner core 8 to make it descend, and further the ejector rod 9 descends to push down the top plate 7. The movable stopper 4 can be pulled by the traction belt 6 to change from the vertical state to the horizontal state. At this time, the movable stopper 4 and the outer sleeve column 2 are respectively located on the two sides of A and B. Then rotate the central bolt 1 or the outer sleeve column 2 (fix one and rotate the other). The outer sleeve column 2 and the movable stopper 4 are respectively pressed on the surfaces of A and B, so that the bolt can also be installed in the same operating space; after the installation is completed, first rotate the rotating ring 11 to align the locking plug 1401 with the fixing hole 15. The tightening spring 1404 pushes the inner movable plate 1403 to make the inner end of the locking plug 1401 insert into the fixing hole 15. Then insert the positioning plug 13 into the positioning hole 12 at the corresponding position to fix the rotating ring 11. At the same time, the central bolt 1 and the outer sleeve column 2 are also relatively fixed and will not loosen randomly. When the locking plug 1401 is inserted into the fixing hole 15, the airbag convex column 17 is compressed to make the airbag on the inner mounting ring 16 expand and push the inner clamping plate 18 to move. The corrugations on the inner clamping plate 18 are embedded in the clamping groove 19, and the inner core 8 can be fixed to prevent rotational loosening after the device is installed.

[0037] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A bolt device for power distribution with a multi-stage locking mechanism, comprising a central bolt and an outer sleeve column. The central bolt is inserted into the outer sleeve column, and the threaded column at the bottom of the central bolt is connected to the inner wall of the outer sleeve column through internal and external thread cooperation. It is characterized in that: The interior of the central bolt is a hollow structure, and an adjustable stopper mechanism is arranged inside the central bolt; An installation groove is provided at the upper end of the outer sleeve column, a rotating ring is rotatably installed in the installation groove, and a locking mechanism is arranged on the rotating ring, and the locking mechanism is used to lock the outer sleeve column and the stopper mechanism inside the outer sleeve column.

2. The bolt device for power distribution according to claim 1, which is characterized in that: Anti-slip grooves are formed on the side wall of the outer sleeve column.

3. The bolt device for power distribution according to claim 1, which is provided with a multi-stage locking mechanism, is characterized in that: A buffer cushion ring is connected to the bottom of the outer sleeve column, and the buffer cushion ring is used for buffering and anti-slip.

4. A power distribution bolt device with a multi-stage locking mechanism according to claim 1, characterized in that: The stopper mechanism includes several movable stoppers. Several bottom side grooves are formed at the bottom end of the threaded column part of the central bolt. One movable stopper is arranged in each bottom side groove. A groove is formed at one end of the movable stopper located inside the central bolt. A connecting shaft is arranged in the groove, a traction belt is fixed on the connecting shaft, and the end of the traction belt is connected to a top plate; The stopper mechanism further includes a driving component arranged inside the central bolt. The driving component is used to adjust the position state of the movable stopper. The driving component includes an inner core. The diameter of the lower section of the inner core is larger than that of the upper section. Threads are formed on the side wall of the lower section of the inner core. The lower section of the inner core and the inner side wall of the central bolt are connected by internal and external thread cooperation. A top rod is connected to the bottom of the inner core. The top rod corresponds to the top plate. By rotating the inner core to make it descend, the top rod descends and pushes the top plate downward. The movable stopper can be pulled by the traction belt to change from a vertical state to a horizontal state. A limiting support ring is arranged on the side wall at the bottom end of the central bolt, and the limiting support ring is used to limit the movable stopper.

5. A distribution and power supply bolt device with a multi-stage locking mechanism according to claim 4, characterized in that: The movable stopper is rotatably installed in the bottom side groove through a rotating shaft on the side wall.

6. The bolt device for power distribution according to claim 4, which is provided with a multi-stage locking mechanism, is characterized in that: An anti-slip pad is arranged on the upper surface of the end of the movable stopper.

7. A power distribution bolt device with a multi-stage locking mechanism according to claim 4, characterized in that: The traction belt is a flexible high-strength traction wire. The diameter of the traction belt is 1-2 mm. The traction belt is made of one of aramid fiber, ultra-high molecular weight polyethylene fiber, and multi-strand braided fine metal wire rope.

8. A power distribution bolt device with a multi-stage locking mechanism according to claim 1, characterized in that: Several positioning holes are formed on the bottom surface of the installation groove. A positioning plug is movably inserted on the rotating ring, and the positioning plug is correspondingly inserted into the positioning hole. The bottom of the positioning plug is a permanent magnet, and the bottom of the positioning plug is adsorbed inside the positioning hole.

9. A power distribution bolt device with a multi-stage locking mechanism according to claim 1, characterized in that: The locking mechanism includes a locking component installed on the rotating ring. A cavity is arranged inside the rotating ring. The locking component includes a locking plug column that movably penetrates through the cavity. A pulling block is arranged at the outer end of the locking plug column, and the pulling block is used for the user to dial. An inner movable plate is arranged on the part of the locking plug column located in the cavity. A group of tightening springs are connected to the side wall of the inner movable plate. A fixing hole is formed on the side wall at the connection between the threaded column and the screw head of the central bolt. The inner end of the locking plug column corresponds to the fixing hole. After the device is installed, first rotate the rotating ring to align the locking plug column with the fixing hole. The tightening spring pushes the inner movable plate to make the inner end of the locking plug column insert into the fixing hole. Then insert the positioning plug into the positioning hole at the corresponding position, and the rotating ring can be fixed. At the same time, the central bolt and the outer sleeve column are also relatively fixed and will not loosen randomly.

10. A distribution and power supply bolt device with a multi-stage locking mechanism according to claim 4, characterized in that: A circumferential clamping groove is formed on the upper side wall of the inner core. An inner mounting ring is embedded and installed on the inner side wall at the connection of the threaded column and the screw head of the central bolt. Several annular expandable air bags are arranged on the inner wall of the inner mounting ring. An inner clamping plate is connected to the air bag. The inner clamping plate is embedded and installed on the inner wall of the inner mounting ring. The inner clamping plate can only move in and out relative to the inner mounting ring and cannot move left and right. A clamping rib is arranged on the inner side wall of the inner clamping plate. The clamping rib corresponds to the clamping groove. An air bag convex column is connected to the outer wall of the inner mounting ring. The air bag convex column is located in the fixing hole. When the locking plug is inserted into the fixing hole, the air bag convex column is compressed, so that the air bag on the inner mounting ring expands and pushes the inner clamping plate to move. The clamping rib on the inner clamping plate is embedded in the clamping groove, and the inner core can be fixed to prevent rotation and loosening after the device is installed.

11. A power distribution bolt device with a multi-stage locking mechanism according to claim 10, characterized in that: The diameter of the air bag convex column is larger than the inner diameter of the opening of the fixing hole, so that when one air bag convex column is compressed, if there are multiple air bag convex columns, the other air bag convex columns will not expand and elongate, and only the air bag on the inner mounting ring can expand.

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