CN222565499U - A multifunctional exhibition display stand - Google Patents

Abstract

The utility model belongs to the technical field of exhibition equipment and discloses a multifunctional exhibition display stand, which comprises a transportation main board and a display platform, wherein two groups of support boards are arranged on the upper surface of the transportation main board, clamping grooves are formed in the lower surface of the display platform, the top ends of the two groups of support boards are slidably connected in the clamping grooves of the display platform, a limiting mechanism for limiting displayed objects is arranged on the upper surface of the display platform, the clamping grooves are formed in the upper surface of the transportation main board, a driving mechanism for driving the display platform and the limiting mechanism to rotate is arranged in the clamping grooves of the transportation main board, a protection mechanism is arranged on the outer surface of the display platform, and the driving mechanism can be detached from the joint of the display platform and the transportation main board in the using process, so that the driving mechanism can be replaced and maintained by subsequent staff conveniently, and the time consumed by the subsequent staff in maintaining the device is reduced.

Description

Multifunctional exhibition stand

Technical Field

The utility model relates to the technical field of exhibition equipment, in particular to a multifunctional exhibition stand.

Background

In the exhibition, the merchant can place commodity through the show stand and show, in order to enable the viewer to carry out audio-visual understanding to commodity fast, improves user experience, generally can be used for rotating the article of show through rotatory show stand to make the better show in the eyes of viewer of each angle of article.

The utility model discloses a multifunctional exhibition product display stand, which comprises a main board, a fixing component and a rotating component, wherein baffle plates are fixedly arranged at two ends of the main board, the outer ends of the baffle plates are provided with the fixing component, a pushing handle is fixedly arranged at the upper end of the fixing component, a fixing rod is fixedly arranged in the middle of the pushing handle, a moving component is arranged at the bottom of the main board, and an exhibition stand I is arranged at the upper end of the main board. According to the utility model, the fixed assembly and the rotating assembly are arranged, the fixed assembly is in telescopic adjustment through the fixed column, the rotating assembly is matched with the rotating wheel through the rotating groove to achieve a rotatable effect, and the problems that a viewer cannot see clearly due to a visual field blind area, the display stand is easy to move at will, and the display stand upper end exhibits are difficult to protect are solved.

In the process of realizing the application, the technology has the following problems that the existing multifunctional exhibition product display table mostly rotates by driving the display platform through the starting motor, so that the problem that viewers cannot see clearly due to a visual field blind area is solved, but the driving motor at the lower end of most display tables cannot be disassembled, so that the whole display table needs to be replaced when the subsequent driving motor is damaged, and the practicability of the equipment is reduced.

Therefore, a multifunctional exhibition stand is provided.

Disclosure of utility model

The utility model aims to solve the problem that the drive motor at the lower end of most display tables cannot be disassembled, so that the whole display table needs to be replaced when the subsequent drive motor is damaged.

The utility model adopts the following technical scheme for realizing the purposes:

The utility model provides a multi-functional meeting exhibition stand, includes transportation mainboard and show platform, the last surface mounting of transportation mainboard has two sets of backup pads, the draw-in groove has been seted up to the lower surface of show platform, two sets of the top sliding connection of backup pad is in inside the draw-in groove of show platform, the last surface mounting of show platform has the stop gear who restricts the show article, the draw-in groove has been seted up to the upper surface of transportation mainboard, the draw-in groove internally mounted joint of transportation mainboard has the drive show platform reaches stop gear carries out pivoted actuating mechanism, the surface mounting of show platform has protection machanism, the draw-in groove has all been seted up to protection machanism's left and right sides, the cooling machanism is all installed to protection machanism's two sets of draw-in inside, protection machanism's inside is provided with positioning mechanism.

Further, actuating mechanism includes fixed plate and locating piece, the locating piece joint is in inside the draw-in groove of transportation mainboard, the fixed plate is installed the upper surface of locating piece, the upper surface of fixed plate is provided with motor two, electric telescopic handle is installed to the output shaft of motor two, fixed block one is installed to electric telescopic handle's output, the surface joint of fixed block one has fixed block two, fixed block two is installed the lower surface of show platform.

Further, stop gear includes the show board, the show board is installed the upper surface of show platform, the draw-in groove has been seted up to the upper surface of show board, the through-hole has all been seted up to the left and right sides inner wall of show board draw-in groove, the inside rotation of two sets of through-holes of show board is connected with two sets of threaded rods one, the outside threaded connection of two sets of connecting blocks one of threaded rod, the connecting rod is installed to the right-hand member of two threaded rods one, the connecting rod is kept away from one end of two threaded rods one installs the handle, is close to a set of upper surface mounting of connecting block one has the connecting plate, the connecting plate is kept away from one side of handle has seted up flutedly, the through-hole has all been seted up to both sides inner wall around the connecting plate recess, the inside rotation of two sets of through-holes of connecting plate is connected with two sets of threaded rods two connecting blocks two, the back of connecting plate installs motor one, the output of motor one is installed the back of two threaded rods.

Further, the protection mechanism comprises a fixing rod and a fixing ring, the fixing rod is installed on the outer surface of the display platform, the fixing ring is connected to the outer surface of the fixing rod in a sliding mode, and the lower surface of the fixing ring abuts against the upper surface of the transportation main board.

Further, two sets of the cooling mechanism includes back font fixed plate, the draw-in groove has all been seted up to the left and right sides of fixed ring, and two sets of back font fixed plate is installed respectively inside two sets of draw-in grooves of fixed ring, two sets of the filter screen is all installed to the inside of back font fixed plate.

Further, positioning mechanism includes stopper and bolt, the dead lever is kept away from the draw-in groove has been seted up to one side of show platform, stopper sliding connection is in inside the draw-in groove of dead lever, the inner wall top of dead lever draw-in groove is seted up flutedly, surface mounting has spacing slider on the stopper, spacing slider sliding connection is in inside the recess of dead lever, the stopper is close to one side of show platform installs the spring telescopic link, the spring telescopic link is close to one side of show platform is installed the dead lever is close to one side inner wall of show platform, the dead lever reaches the through-hole has all been seted up to the upper surface of stopper, the bolt is pegged graft the dead lever with inside the through-hole of stopper, the lower surface butt of stopper is in the upper surface of fixed ring.

The beneficial effects of the utility model are as follows:

1. According to the utility model, the first fixing block is pushed to move by starting the electric telescopic rod, the first fixing block is clamped into the second fixing block, and then the second fixing block and the display platform are driven to synchronously rotate by starting the second motor, so that the device can rotate and display the display objects in the using process, the first fixing block is moved out of the second fixing block by starting the electric telescopic rod, and then the positioning block is driven to move out of the clamping groove of the transportation main board by pulling the fixing plate, so that the driving mechanism can be detached from the position between the transportation main board and the display platform in the using process, and the driving mechanism is convenient to maintain by subsequent staff, so that the practicability of the device is improved.

2. According to the utility model, the rotating handle is started to drive the first connecting blocks to move, one adjacent sides of the first connecting blocks are respectively abutted against the left side and the right side of the display article, the first motor is started to drive the second connecting blocks to move, and one adjacent sides of the second connecting blocks are respectively abutted against the front side and the rear side of the display article at the upper end of the display plate, so that the limiting mechanism limits the moving position of the display article placed at the upper end of the display platform, and the movement of the article at the upper end of the display plate in the rotating process of the display platform is avoided as much as possible, so that the stability of the display article in the rotating display process is improved.

Drawings

FIG. 1 is a schematic top plan view of the present utility model;

FIG. 2 is a schematic side elevational view of the present utility model;

FIG. 3 is a schematic side elevational view of the drive mechanism of the present utility model;

FIG. 4 is a schematic side elevational view of the spring telescoping rod of the present utility model;

fig. 5 is an enlarged view of the utility model at a in fig. 2.

The device comprises a transportation main board, a display platform, a support board, a limit mechanism, 401, a display board, 402, a bi-directional threaded rod I, 403, a connecting rod, 404, a handle, 405, a connecting block I, 406, a connecting plate, 407, a bi-directional threaded rod I, 408, a connecting block II, 409, a motor I, 5, a driving mechanism, 501, a fixing board, 502, a locating block, 503, a motor II, 504, an electric telescopic rod, 505, a fixing block I, 506, a fixing block II, 6, a protection mechanism, 601, a fixed circular ring, 602, a fixing rod, 7, a heat dissipation mechanism, 701, a zigzag fixing board, 702, a filter screen, 8, a locating mechanism, 801, a limit block, 802, a bolt 803, a spring telescopic rod, 804 and a limit sliding block.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present utility model more apparent, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are some embodiments of the present utility model, but not all embodiments of the present utility model. The components of the embodiments of the present utility model generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the utility model, as presented in the figures, is not intended to limit the scope of the utility model, as claimed, but is merely representative of selected embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that like reference numerals and letters refer to like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures. Furthermore, the terms "first," "second," and the like, are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.

In describing embodiments of the present utility model, it should be noted that the directions or positional relationships indicated by the terms "inner", "outer", "upper", etc. are directions or positional relationships based on those shown in the drawings, or those that are conventionally put in place when the inventive product is used, are merely for convenience of description and simplification of description, and are not indicative or implying that the apparatus or element in question must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present utility model.

As shown in fig. 1 to 5, a multifunctional exhibition stand comprises a transportation main board 1 and a display platform 2, wherein two groups of support boards 3 are arranged on the upper surface of the transportation main board 1, clamping grooves are formed in the lower surface of the display platform 2, the top ends of the two groups of support boards 3 are slidably connected inside the clamping grooves of the display platform 2, a limiting mechanism 4 for limiting display objects is arranged on the upper surface of the display platform 2, the clamping grooves are formed in the upper surface of the transportation main board 1, a driving mechanism 5 for driving the display platform 2 and the limiting mechanism 4 to rotate is arranged in the clamping grooves of the transportation main board 1, a protection mechanism 6 is arranged on the outer surface of the display platform 2, clamping grooves are formed in the left side and the right side of the protection mechanism 6, a heat dissipation mechanism 7 is arranged in the two groups of clamping grooves of the protection mechanism 6, and a positioning mechanism 8 is arranged in the protection mechanism 6.

As shown in fig. 1 and 2, the driving mechanism 5 includes a fixing plate 501 and a positioning block 502, the positioning block 502 is clamped in a clamping groove of the transportation main board 1, the fixing plate 501 is mounted on the upper surface of the positioning block 502, a second motor 503 is arranged on the upper surface of the fixing plate 501, an electric telescopic rod 504 is mounted on an output shaft of the second motor 503, a first fixing block 505 is mounted at an output end of the electric telescopic rod 504, a second fixing block 506 is clamped on an outer surface of the first fixing block 505, and the second fixing block 506 is mounted on the lower surface of the display platform 2;

Specifically, after the display object is placed at the upper end of the display platform 2, the first fixing block 505 is pushed to move by starting the electric telescopic rod 504, the first fixing block 505 is clamped into the second fixing block 506, the second fixing block 506 and the display platform 2 are driven to synchronously rotate by starting the motor 503, so that the display object can be rotated and displayed in the using process of the display device, the first fixing block 505 is driven to move by starting the electric telescopic rod 504, the first fixing block 505 is moved out of the second fixing block 506, the positioning block 502 is driven to move out of the clamping groove of the transport main board 1 by pulling the fixing plate 501, the driving mechanism 5 can be detached from the position between the transport main board 1 and the display platform 2 in the using process, and the driving mechanism 5 is maintained by subsequent staff conveniently, so that the practicability of the display device is improved.

As shown in fig. 1 to 3, the limiting mechanism 4 includes a display board 401, the display board 401 is mounted on the upper surface of the display platform 2, a clamping groove is formed in the upper surface of the display board 401, through holes are formed in inner walls of the left side and the right side of the clamping groove of the display board 401, two groups of through holes of the display board 401 are internally connected with a first bidirectional threaded rod 402 in a rotating mode, two groups of connecting blocks 405 are connected to the outer threads of the first bidirectional threaded rod 402, a connecting rod 403 is mounted at the right end of the first bidirectional threaded rod 402, a handle 404 is mounted at one end, far from the first bidirectional threaded rod 402, a connecting plate 406 is mounted on the upper surface, close to the handle 404, of the first connecting block 405, a groove is formed in one side, far from the handle 404, of the connecting plate 406, through holes are formed in the inner walls of the front side and the groove, two sides of the connecting plate 406 are respectively, two groups of through holes of the connecting plate 406 are internally connected with a second bidirectional threaded rod 407 in a rotating mode, two groups of connecting blocks 408 are connected to the outer threads of the second bidirectional threaded rod 407, a motor 409 is mounted at the back of the connecting plate 406, and the output end of the motor 409 is mounted at the back of the second bidirectional threaded rod 407;

Specifically, after the display article is placed at the upper end of the display board 401, the rotating handle 404 is started to drive the two groups of connecting blocks one 405 to move, one adjacent sides of the two groups of connecting blocks one 405 are respectively abutted against the left side and the right side of the display article, the first 409 of the starting motor drives the two groups of connecting blocks two 408 to move, one adjacent sides of the two groups of connecting blocks two 408 are respectively abutted against the front side and the rear side of the display article at the upper end of the display board 401, and the limiting mechanism 4 limits the moving position of the display article placed at the upper end of the display platform 2, so that the movement of the article at the upper end of the display board 401 in the rotating process of the display platform 2 is avoided as much as possible, and the stability of the display article in the rotating display process is improved.

As shown in fig. 1 and 2, the protection mechanism 6 comprises a fixing rod 602 and a fixing ring 601, wherein the fixing rod 602 is mounted on the outer surface of the display platform 2, the fixing ring 601 is slidably connected to the outer surface of the fixing rod 602, the lower surface of the fixing ring 601 is abutted against the upper surface of the transportation main board 1, specifically, when the driving mechanism 5 is mounted at the lower end of the display platform 2, the fixing ring 601 is clamped to the outer end of the fixing rod 602 by pushing the fixing ring 601, and then the lower surface of the fixing ring 601 is abutted against the upper surface of the transportation main board 1 by pushing the fixing ring 601, so that the fixing ring 601 shields the driving mechanism 5 at the lower end of the display platform 2, and the service life of the driving mechanism 5 is prolonged.

As shown in fig. 1 and 2, the two sets of heat dissipation mechanisms 7 include two sets of fixing plates 701 shaped like a Chinese character 'hui', the left and right sides of the fixing ring 601 are provided with clamping grooves, the two sets of fixing plates 701 shaped like a Chinese character 'hui' are respectively arranged in the two sets of clamping grooves of the fixing ring 601, and the interiors of the two sets of fixing plates 701 shaped like a Chinese character 'hui' are respectively provided with a filter screen 702;

Specifically, the outside air of the fixed circular ring 601 is guided to the inside of the fixed circular ring 601 through the two groups of filter screens 702, the positions of the two groups of filter screens 702 are respectively arranged at the left side and the right side of the fixed circular ring 601, so that the air at the left side and the right side of the fixed circular ring 601 keeps circulating in the using process of the fixed circular ring 601, the damage to the driving mechanism 5 caused by too high temperature due to the fact that the air cannot enter the inside of the protection mechanism 6 when the driving mechanism 5 is shielded and protected by the fixed circular ring 601 is avoided as much as possible, the two groups of double-square-shaped fixing plates 701 are respectively clamped in the two groups of clamping grooves of the fixed circular ring 601, a worker drives the two groups of filter screens 702 to move out of the two groups of clamping grooves of the fixed circular ring 601 by pushing the two groups of double-square-shaped fixing plates 701, and the filter screens 702 can be quickly dismounted, and the time consumed by the subsequent worker in cleaning and maintaining the two groups of filter screens 702 is reduced.

As shown in fig. 4 and 5, the positioning mechanism 8 includes a limiting block 801 and a bolt 802, a clamping groove is formed on one side of the fixed rod 602 away from the display platform 2, the limiting block 801 is slidably connected inside the clamping groove of the fixed rod 602, a groove is formed at the top of the inner wall of the clamping groove of the fixed rod 602, a limiting block 804 is mounted on the upper surface of the limiting block 801, the limiting block 804 is slidably connected inside the groove of the fixed rod 602, a spring telescopic rod 803 is mounted on one side of the limiting block 801 close to the display platform 2, a spring telescopic rod 803 is mounted on one side of the fixed rod 602 close to the display platform 2, through holes are formed on the upper surfaces of the fixed rod 602 and the limiting block 801, the bolt 802 is inserted inside the through holes of the fixed rod 602 and the limiting block 801, and the lower surface of the limiting block 801 is abutted against the upper surface of the fixed circular ring 601;

Specifically, the lower surface of the limiting block 801 is abutted against the upper surface of the fixed ring 601, so that the positioning mechanism 8 limits the moving position of the fixed ring 601 at the outer end of the fixed rod 602, and the fixed ring 601 is prevented from moving as much as possible when the fixed ring 601 shields the driving mechanism 5, so that the stability of the fixed ring 601 in the use process is improved; when the staff is dismantling the in-process of removing fixed ring 601, through promoting stopper 801, move the draw-in groove inside to dead lever 602 with the one side that transportation mainboard 1 was kept away from to stopper 801 to move the position of stopper 801 upper end through-hole to dead lever 602 inside through-hole under the dead lever 802, the rethread promotes bolt 802, peg graft the bottom of bolt 802 inside the through-hole of dead lever 602 and stopper 801, make stopper 801 at the inside mobile position of dead lever 602 draw-in groove by bolt 802 restriction, thereby avoid stopper 801 to stop the staff normal safety and tear fixed ring 601 open at the in-process of using as far as possible.

Meanwhile, the moving position of the limiting block 801 in the clamping groove of the fixing rod 602 is limited by the bolt 802, so that a worker does not need to manually support the limiting block 801 in the process of mounting and dismounting the fixing ring 601, and the time consumed by the subsequent worker in mounting and dismounting the fixing ring 601 is reduced.

In sum, the first fixing block 505 is pushed to move by starting the electric telescopic rod 504, the first fixing block 505 is clamped into the second fixing block 506, the second fixing block 506 and the display platform 2 are driven to synchronously rotate by starting the second motor 503, so that the device can rotate and display the display objects in the using process, the first fixing block 505 is driven to move by starting the electric telescopic rod 504, the first fixing block 505 is moved out of the second fixing block 506, the positioning block 502 is driven to move out of the clamping groove of the transport main board 1 by pulling the fixing plate 501, the driving mechanism 5 can be detached from the space between the transport main board 1 and the display platform 2 in the using process, and accordingly maintenance of the driving mechanism 5 by subsequent staff is facilitated.

Simultaneously, the rotating handle 404 is started to drive the two groups of first connecting blocks 405 to move, one sides of the two groups of first connecting blocks 405 adjacent to each other are respectively abutted to the left side and the right side of a displayed object, the first starting motor 409 is used to drive the two groups of second connecting blocks 408 to move, one sides of the two groups of second connecting blocks 408 adjacent to each other are respectively abutted to the front side and the rear side of the displayed object at the upper end of the display platform 401, the limiting mechanism 4 limits the moving position of the displayed object placed at the upper end of the display platform 2, and therefore the object at the upper end of the display platform 401 is prevented from moving in the rotating process as much as possible, the fixed ring 601 is clamped to the outer end of the fixed rod 602 by pushing the fixed ring 601, the lower surface of the fixed ring 601 is abutted to the upper surface of the transportation main board 1, and the fixed ring 601 shields the driving mechanism 5 at the lower end of the display platform 2, and the service life of the driving mechanism 5 is prolonged.

In addition, the lower surface of the limiting block 801 is abutted against the upper surface of the fixed circular ring 601, so that the positioning mechanism 8 limits the moving position of the fixed circular ring 601 at the outer end of the fixed rod 602, and the fixed circular ring 601 is prevented from moving when the fixed circular ring 601 shields the driving mechanism 5 as much as possible.

The foregoing has shown and described the basic principles, principal features and advantages of the utility model. It will be understood by those skilled in the art that the present utility model is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present utility model, and various changes and modifications may be made therein without departing from the spirit and scope of the utility model, which is defined by the appended claims. The scope of the utility model is defined by the appended claims and equivalents thereof.

Claims (6)

1. The utility model provides a multifunctional exhibition show stand, includes transportation mainboard (1) and show platform (2), its characterized in that, the last surface mounting of transportation mainboard (1) has two sets of backup pad (3), the draw-in groove has been seted up to the lower surface of show platform (2), two sets of the top sliding connection of backup pad (3) is in inside the draw-in groove of show platform (2), the last surface mounting of show platform (2) has stop gear (4) that restrict show article, the draw-in groove has been seted up to the upper surface of transportation mainboard (1), the draw-in groove internally mounted joint of transportation mainboard (1) has the drive show platform (2) with stop gear (4) carry out pivoted actuating mechanism (5), the surface mounting of show platform (2) has protection machanism (6), the draw-in groove has all been seted up in both sides of protection machanism (6), heat dissipation mechanism (7) are all installed to the inside of two sets of draw-in grooves of protection machanism (6), the inside of protection machanism (6) is provided with positioning mechanism (8).

2. The multifunctional exhibition stand according to claim 1, wherein the driving mechanism (5) comprises a fixed plate (501) and a positioning block (502), the positioning block (502) is clamped inside a clamping groove of the transportation main board (1), the fixed plate (501) is installed on the upper surface of the positioning block (502), a motor II (503) is arranged on the upper surface of the fixed plate (501), an electric telescopic rod (504) is installed on an output shaft of the motor II (503), a fixed block I (505) is installed at an output end of the electric telescopic rod (504), a fixed block II (506) is clamped on the outer surface of the fixed block I (505), and the fixed block II (506) is installed on the lower surface of the exhibition stand (2).

3. The multifunctional exhibition stand according to claim 1, wherein the limiting mechanism (4) comprises a display plate (401), the display plate (401) is mounted on the upper surface of the display platform (2), a clamping groove is formed in the upper surface of the display plate (401), through holes are formed in the inner walls of the left side and the right side of the clamping groove of the display plate (401), a first two-way threaded rod (402) is rotatably connected to the inner walls of the two groups of through holes of the display plate (401), two first two-way threaded rod (405) are connected to the external threads of the first two-way threaded rod (402) in a connecting mode, a connecting rod (403) is mounted at the right end of the first two-way threaded rod (402), a connecting plate (406) is mounted on the upper surface of one group of connecting rod (405) close to the handle (404), grooves are formed in one side of the connecting plate (406), through holes are formed in the inner walls of the front and the back of the grooves of the connecting plate (406), two groups of threaded rods (407) are rotatably connected to the two connecting plates (407) in a back face of the two-way threaded rod (407), the output end of the first motor (409) is arranged on the back of the second bidirectional threaded rod (407).

4. The multifunctional exhibition stand according to claim 1, wherein the protection mechanism (6) comprises a fixing rod (602) and a fixing ring (601), the fixing rod (602) is installed on the outer surface of the exhibition stand (2), the fixing ring (601) is slidingly connected to the outer surface of the fixing rod (602), and the lower surface of the fixing ring (601) is abutted to the upper surface of the transportation main board (1).

5. The multifunctional exhibition stand according to claim 4, wherein the two groups of heat dissipation mechanisms (7) comprise a back-shaped fixing plate (701), clamping grooves are formed in the left side and the right side of the fixing ring (601), the two groups of back-shaped fixing plates (701) are respectively arranged in the two groups of clamping grooves of the fixing ring (601), and filter screens (702) are respectively arranged in the two groups of back-shaped fixing plates (701).

6. The multifunctional exhibition stand according to claim 4, wherein the positioning mechanism (8) comprises a limiting block (801) and a plug pin (802), a clamping groove is formed in one side, far away from the exhibition platform (2), of the fixing rod (602), the limiting block (801) is slidably connected inside the clamping groove of the fixing rod (602), a groove is formed in the top of the inner wall of the clamping groove of the fixing rod (602), a limiting block (804) is mounted on the upper surface of the limiting block (801), the limiting block (804) is slidably connected inside the groove of the fixing rod (602), a spring telescopic rod (803) is mounted on one side, close to the exhibition platform (2), of the limiting block (801), one side, close to the exhibition platform (2), of the fixing rod (602), through holes are formed in the upper surfaces of the fixing rod (602) and the plug pin (801), and the upper surface, abutting against the inner surface (601) of the limiting block (801), of the fixing rod (602) is inserted into the circular ring (601).