CN216841543U

CN216841543U - Hole sealing device for investigation drilling in limestone area

Info

Publication number: CN216841543U
Application number: CN202220340272.6U
Authority: CN
Inventors: 张九会; 黄侄祥; 陈佳嘉; 袁亮; 兰贤东; 陈成博; 赵仁基
Original assignee: Wenzhou Engineering Investigation Institute Co ltd
Current assignee: Wenzhou Engineering Investigation Institute Co ltd
Priority date: 2022-02-19
Filing date: 2022-02-19
Publication date: 2022-06-28
Anticipated expiration: 2032-02-19

Abstract

The utility model relates to a technical field of hole sealing device for drilling discloses a hole sealing device for limestone area reconnaissance drilling, and it is including sealing the hole frame, sealing ball and impeller, the hole sealing frame includes the pushing ram, can dismantle the spliced pole of connection on the pushing ram and set up a plurality of telescopic links on the spliced pole, the one end of telescopic link is fixed on the circumference lateral wall of spliced pole, a plurality of the one end that the spliced pole was kept away from to the telescopic link is circumference distribution around the axis of spliced pole, self length direction extension or shortening can be followed to the telescopic link, still be provided with the drive assembly who is used for driving the telescopic link extension or shortens on the hole sealing frame. The situation that the plugging object falls into the karst cave can be reduced.

Description

Hole sealing device for investigation and drilling in limestone area

Technical Field

The application relates to the technical field of hole sealing device for drilling, in particular to a hole sealing device for investigation in a limestone area.

Background

And (4) the karst cave in the limestone area develops, and after the exploration drilling is finished, hole sealing treatment needs to be carried out on the drilling. If no hole sealing is carried out, the exploration drill hole becomes a groundwater circulation channel, soil mass on an upper covering layer flows to a karst cave through the drill hole under the driving of groundwater, a soil cave is easily formed, the exploration drill hole becomes an important factor inducing the soil cave in engineering, and therefore the exploration drill hole needs to be sealed.

In the related art, the sealing treatment is usually performed by grouting after the sealing of the bag-shaped object. The grouting measure after the bag-shaped object is blocked is generally that a cement bag or a gunny bag is filled with a certain amount of cement and then made into a cylinder shape, a drill rod is used for conveying the cylinder-shaped object to a limestone surface to form a water-resisting channel, then the cylinder-shaped object is grouted, and after the grout is solidified, the hydraulic connection between an upper covering layer and karst water is cut off, so that a drilled hole is prevented from forming a karst water channel.

With respect to the above-described related art, the inventors consider that the following drawbacks exist: the bag-shaped object plugging head often causes the whole plugging head to fall into a karst cave due to deformation or uneven rock surface; and the slurry easily flows into the karst cave along the contact surface, so that the effect of plugging the drilling hole cannot be achieved.

SUMMERY OF THE UTILITY MODEL

In order to reduce the condition emergence that the shutoff thing fell into the solution cavity, this application provides a hole sealing device of limestone area reconnaissance drilling.

The application provides a hole sealing device of rock ash area reconnaissance drilling adopts following technical scheme:

the utility model provides a hole sealing device is used in investigation drilling in limestone area, includes the hole sealing frame, seals hole ball and impeller, the hole sealing frame includes the pushing ram, can dismantle the spliced pole of connection on the pushing ram and set up a plurality of telescopic links on the spliced pole, the one end of telescopic link is fixed on the circumference lateral wall of spliced pole, a plurality of the one end that the spliced pole was kept away from to the telescopic link is circumference around the axis of spliced pole and distributes, self length direction extension or shortening can be followed to the telescopic link, still be provided with the drive assembly who is used for driving the telescopic link extension or shortens on the hole sealing frame.

Through adopting above-mentioned technical scheme, when needing to carry out the hole sealing to the reconnaissance drilling, the propulsion pole that is connected with the telescopic link earlier stretches into in the hole, make the telescopic link down in this operation, when the telescopic link reachs the drilling diapire, use drive assembly, lengthen the telescopic link, when the circumscribed circle diameter of each telescopic link is greater than the drilling aperture, the telescopic link can insert on the drilling pore wall under drive assembly's drive, under the pore wall of drilling blocks, the mounting bracket is fixed in the drilling and is difficult for falling into the solution cavity, at last rethread hole sealing ball and propeller carry out the shutoff to drilling. In addition, the propelling rod is detachably connected with the connecting column, and when the telescopic rod reaches the specified position of the drilled hole, the propelling rod can be detached and the hole can be taken out, so that the hole can be plugged on the next step.

Optionally, the telescopic link includes a plurality of slip cap's removal sleeve pipe in proper order, drive assembly includes the actuating lever and can dismantle the fixed column of connection on the actuating lever, the equal slip cap of actuating lever and fixed column is established outside the pushing ram, it is connected with tensile strip to rotate on the circumference lateral wall of fixed column, the one end that the actuating lever was kept away from to tensile strip is rotated and is connected on the removal sleeve pipe of keeping away from spliced pole one end, the quantity of tensile strip is the same with the quantity of telescopic link.

Through adopting above-mentioned technical scheme, when the telescopic link stretched into in the drilling, promote the actuating lever and remove to the one side that is close to the spliced pole, the one end of connecting the tensile strip on the fixed column this moment is removed downwards, and the tensile strip other end can not remove downwards under the blockking of telescopic link, then tensile strip can elongate the telescopic link under the thrust effect of actuating lever, thereby make tensile pole keep away from on the one end of spliced pole inserts the drilling pore wall, thereby make the mounting bracket be difficult for falling into in the solution cavity, above-mentioned process operation is simple, and is convenient. Can dismantle between actuating lever and the fixed column in addition and be connected, when the telescopic link reachd the appointed degree of depth of drilling, can pull down the actuating lever from the fixed column to carry out hole sealing processing on next step.

Optionally, one end of the movable sleeve extending into the adjacent movable sleeve is provided with a clamping table, and the other end of the movable sleeve is provided with a limiting ring for preventing the clamping table of the adjacent movable sleeve from dropping off.

By adopting the technical scheme, when two adjacent movable sleeves are mutually sleeved together, the clamping table is mutually abutted to the limiting ring, and the movable sleeves are not easy to separate from the adjacent movable sleeves which slide and stretch into the movable sleeves under the blocking of the limiting ring.

Optionally, one end fixedly connected with anticreep piece that the actuating lever is close to the fixed column, set up the fixed orifices that supplies the actuating lever to stretch into on the fixed column, set up the anticreep groove that supplies the embedding of anticreep piece on the pore wall of fixed orifices, the anticreep groove includes embedding portion and the anticreep portion that communicates each other, the extending direction of embedding portion and anticreep portion is different.

Through adopting above-mentioned technical scheme, when stretching into the fixed orifices with the actuating lever, anticreep piece on the actuating lever can stretch into the embedding part in anticreep groove, rotates the actuating lever after that and makes the anticreep portion in anticreep piece embedding anticreep groove, under the blockking of anticreep portion cell wall, realizes relatively fixed between actuating lever and the fixed column.

Optionally, the push rod is close to the one end fixedly connected with connecting block of spliced pole, the mounting groove that supplies the push rod to stretch into is seted up to the one end of spliced pole, set up the spread groove that supplies the connecting block embedding on the cell wall of mounting groove, the spread groove includes the portion and spacing portion of stretching into of intercommunication each other, the extending direction of the portion of stretching into and spacing portion is different.

Through adopting above-mentioned technical scheme, when assembling the telescopic link to the spliced pole on, aim at the spread groove with the connecting block earlier, stretch into the mounting groove with the telescopic link again, in the connecting block stretches into the portion of stretching into of spread groove simultaneously, rotate the telescopic link after that for the connecting block stretches into the spacing portion of spread groove, spacing portion blocks that the telescopic link is deviate from the mounting groove along the direction of keeping away from the spliced pole. The assembling process is simple and convenient.

Optionally, a positioning assembly for controlling the hole sealing depth is arranged on the pushing rod.

Through adopting above-mentioned technical scheme, when needing to carry out the shutoff to the reconnaissance drilling of specific degree of depth, adjust the position of locating component on the pushing ram earlier, stretch into the drilling with the pushing ram to can control the degree of depth of hole sealing.

Optionally, the positioning assembly includes a positioning disk, the outer diameter of the positioning disk is larger than the size of the hole diameter of the drill hole, a positioning thread is arranged on the circumferential side wall of one end, close to the positioning disk, of the pushing rod, a positioning bolt matched with the positioning thread is arranged on the positioning thread, a moving rod is arranged at one end, far away from the fixed column, of the driving rod, a moving hole for the moving rod to slide and penetrate is formed in the positioning disk, a positioning hole for the pushing rod to slide and penetrate is formed in the positioning disk, and the inner diameter of the positioning hole is smaller than the diameter of an outer circle of the positioning bolt.

Through adopting above-mentioned technical scheme, when needing to carry out the hole sealing to the reconnaissance drilling of setting for the degree of depth and handling, pass locating hole, carriage release lever with the propulsion pole earlier and pass the removal hole, adjust the position of positioning bolt on the positioning thread according to setting for the degree of depth again, then stretch into the drilling with the mounting bracket, when the telescopic link reachs appointed degree of depth, the positioning disk can cover on drilling with ground butt to stop the telescopic link and continue to get into drilling depths. Meanwhile, the movable rod is pushed to one side far away from the positioning disc, so that the telescopic rod is driven to be inserted into the hole wall of the drilled hole.

Optionally, the hole sealing ball comprises a clay ball, and the diameter of the hole sealing ball is smaller than the bore diameter of the drill hole.

Through adopting above-mentioned technical scheme, when the telescopic link inserted the drilling pore wall, in filling the drilling with the hole sealing ball, the hole sealing ball can carry out the shutoff to the drilling, and the telescopic link also can block in the hole sealing ball falls into the solution cavity. In addition, the hole sealing ball is a clay ball, and the clay has a certain water-resisting effect and can prevent water flow from eroding the drilled hole.

Optionally, the outer layer of clay ball wraps up the elastic anti-falling membrane of one deck, the one end that the anti-falling membrane is close to the impeller is equipped with the opening.

Through adopting above-mentioned technical scheme, prevent falling the membrane and can block that the clay ball falls into the solution cavity from the space between the telescopic link, prevent falling the membrane simultaneously and have elasticity, make it scatter along with the clay ball for the better laminating of clay ball and drilling pore wall.

In summary, the present application includes at least one of the following beneficial technical effects:

1. the telescopic rod can be inserted into the hole wall of the drilled hole after being stretched, so that the telescopic rod has the effects of bearing the hole sealing ball and preventing the hole sealing ball from falling into the karst cave easily;

2. the hole sealing ball is a clay ball, and the clay ball has a certain water-proof effect and can prevent water flow from corroding the drilled hole.

Drawings

Fig. 1 is a schematic overall structure diagram of an embodiment of the present application.

FIG. 2 is a schematic view of the sealing process using the embodiment of the present application.

Fig. 3 is an exploded view highlighting the anti-run-off slots in the embodiments of the present application.

FIG. 4 is an exploded view highlighting the attachment slot in the embodiment of the present application.

Fig. 5 is an enlarged view of a portion a in fig. 4.

Description of reference numerals:

1. a push rod; 11. connecting blocks; 12. positioning the screw thread; 13. positioning the bolt; 2. connecting columns; 21. mounting grooves; 211. connecting grooves; 2111. an insertion portion; 2112. a limiting part; 3. a telescopic rod; 31. moving the sleeve; 311. clamping a platform; 312. a limiting ring; 4. a drive rod; 41. an anti-drop block; 42. a travel bar; 5. fixing a column; 51. stretching the strip; 52. a fixing hole; 521. a drop-proof groove; 5211. an insertion section; 5212. an anti-drop part; 6. positioning a plate; 61. positioning holes; 62. moving the hole; 7. clay balls; 71. preventing the membrane from falling; 8. and a pusher.

Detailed Description

The present application is described in further detail below with reference to figures 1-5.

The embodiment of the application discloses hole sealing device for investigation of limestone area. Referring to fig. 1 and 2, above-mentioned hole sealing device is including sealing the hole frame, hole sealing ball and impeller 8, the hole sealing frame includes pushing ram 1, can dismantle spliced pole 2 and the eight telescopic links 3 of fixed connection on spliced pole 2 of connection on pushing ram 1, the one end fixed connection of every telescopic link 3 is on spliced pole 2's circumference lateral wall, the other end of telescopic link 3 is the circumference equipartition around spliced pole 2's axis, every telescopic link 3 is all perpendicular with spliced pole 2.

Referring to fig. 3, the telescopic rod 3 can be extended or shortened along its length direction. The telescopic rod 3 comprises four moving sleeves 31 which are sequentially sleeved in a sliding manner, wherein one end of one moving sleeve 31 is arranged in the adjacent moving sleeve 31 in a sliding manner in a penetrating manner, and the other end of the moving sleeve 31 is sleeved in the adjacent moving sleeve 31 in a sliding manner. A clamping table 311 is arranged at one end of the movable sleeve 31 extending into the adjacent movable sleeve 31, and a limiting ring 312 for preventing the clamping table 311 from dropping out of the movable sleeve 31 is arranged on the inner side wall of the other end of the movable sleeve 31. The four moving sleeves 31 are sequentially sleeved together to form the telescopic rod 3, and the moving sleeves 31 at the two ends of the telescopic rod 3 are pulled to one side far away from or close to each other to elongate or shorten the telescopic rod 3.

Referring to fig. 3, the hole sealing frame is further provided with a driving assembly for driving the telescopic rod 3 to extend or contract. Drive assembly includes actuating lever 4 and can dismantle fixed column 5 of connection on actuating lever 4, fixed column 5 is located actuating lever 4 and is close to one side of spliced pole 2, actuating lever 4 and the equal slip cap of fixed column 5 are established outside pushing ram 1, it has tensile strip 51 to articulate on the circumference lateral wall of fixed column 5, the quantity of tensile strip 51 is the same with the quantity of telescopic link 3, the one end that actuating lever 4 was kept away from to tensile strip 51 articulates on the removal sleeve pipe 31 that spliced pole 2 one end was kept away from to telescopic link 3.

Referring to fig. 3, when the driving rod 4 is pushed to a side close to the telescopic rod 3, the fixed column 5 also moves to a side close to the telescopic rod 3 along with the driving rod 4, one end of the tension bar 51 connected to the fixed column 5 moves to a side close to the telescopic rod 3, and the other end of the tension bar 51 is not easily moved in the length direction of the push rod 1 under the block of the telescopic rod 3, so that the tension bar 51 moves in the length direction of the telescopic rod 3, thereby elongating the telescopic rod 3. Also, when the drive lever 4 is pushed to the side away from the telescopic link 3, the telescopic link 3 is shortened.

Referring to fig. 3, when the hole sealing treatment is needed to be carried out on the exploration drilling hole, the hole sealing frame firstly extends into the drilling hole, the telescopic rod 3 extends into the bottom of the drilling hole, and one side, away from the telescopic rod 3, of the push rod 1 is located at the opening of the drilling hole. Then to pushing away the actuating lever 4 to one side that is close to telescopic link 3, then tensile strip 51 can elongate telescopic link 3, and the one end of keeping away from spliced pole 2 of telescopic link 3 can insert on the drilling pore wall under the pulling force effect this moment to fix telescopic link 3 in the drilling bottom, make telescopic link 3 be difficult for falling into the solution cavity.

Referring to fig. 3, the anti-drop block 41 is integrally formed at one end of the driving rod 4 close to the fixing column 5, the fixing column 5 is provided with a fixing hole 52 into which the driving rod 4 extends, the hole wall of the fixing hole 52 is provided with an anti-drop groove 521 into which the anti-drop block 41 is inserted, the anti-drop groove 521 comprises an embedding portion 5211 and an anti-drop portion 5212 which are communicated with each other, and the extending directions of the embedding portion 5211 and the anti-drop portion 5212 are different. During the assembly hole sealing frame, stretch into drive lever 4 in the fixed orifices 52 earlier, anticreep piece 41 can stretch into the embedding portion 5211 of anticreep groove 521 simultaneously, then rotates drive lever 4, and anticreep piece 41 moves to anticreep portion 5212 in anticreep groove 521, and under the blockking of anticreep portion 5212 cell wall, drive lever 4 is difficult for deviating from fixed column 5 along self length direction this moment. When the telescopic rod 3 is assembled in place, the driving rod 4 can be rotated to remove the driving rod 4 from the fixed column 5, so that the next hole sealing treatment can be carried out.

Referring to fig. 3, 4 and 5, one end of the push rod 1 close to the connection column 2 is integrally formed with a connection block 11, the connection column 2 is provided with a mounting groove 21 for the push rod 1 to extend into, a connection groove 211 for the connection block 11 to be embedded into is provided on a groove wall of the mounting groove 21, the connection groove 211 comprises an extension portion 2111 and a limiting portion 2112 which are mutually communicated, and the extension directions of the extension portion 2111 and the limiting portion 2112 are different. When assembling push rod 1 to spliced pole 2, earlier stretch into mounting groove 21 with push rod 1 in, make connecting block 11 stretch into the portion 2111 that stretches into of spread groove 211 simultaneously, rotate push rod 1 after that and make connecting block 11 stretch into spacing portion 2112 of spread groove 211, spacing portion 2112's pore wall can block push rod 1 and deviate from spliced pole 2. When the telescopic rod 3 is assembled in the drill hole, the push rod 1 can be rotated to take down the connecting column 2, so that the convenience and the rapidness are realized, and the hole sealing treatment on the next step is conveniently carried out.

Referring to fig. 3, a positioning assembly for controlling the hole sealing depth is arranged on the push rod 1. The positioning assembly comprises a positioning disc 6, and the outer diameter of the positioning disc 6 is larger than the bore diameter of the drill hole. Set up on the positioning disk 6 and supply pushing ram 1 to slide the locating hole 61 of wearing to establish, pushing ram 1 wears out and is provided with location screw thread 12 on the circumference lateral wall of positioning disk 6 one end, and the cover is equipped with the positioning bolt 13 rather than self screw-thread fit on the location screw thread 12. One end fixedly connected with carriage release lever 42 that fixed column 5 was kept away from to actuating lever 4, carriage release lever 42 are located the circumference lateral wall of actuating lever 4, offer on the positioning disk 6 and supply the removal hole 62 that carriage release lever 42 slided and establish.

Referring to fig. 3, when a hole sealing treatment needs to be performed on a prospecting borehole with a specific depth, the push rod 1 firstly penetrates through the positioning hole 61, the moving rod 42 penetrates through the moving hole 62, then the position of the positioning bolt 13 on the positioning thread 12 is adjusted according to the hole sealing position, then the push rod 1 connected with the connecting column 2 extends into the borehole, and the positioning disc 6 covers the opening of the borehole; when the push rod 1 reaches the designated depth, the positioning bolt 13 is abutted against the side wall of the positioning plate 6 far away from the drill hole, the positioning plate 6 can prevent the push rod 1 from continuously moving downwards, and the position of the push rod 1 is relatively fixed at the moment.

Referring to fig. 2, the hole sealing ball includes clay ball 7, and the diameter of clay ball 7 is less than the drilling aperture for clay ball 7 can put into the drilling smoothly, and the outer parcel one deck elastic anti-falling membrane 71 of clay ball 7, the one end that anti-falling membrane 71 is close to the propeller is equipped with the opening. When the hole sealing frame is assembled in place, the end part of the telescopic rod 3 is inserted into the hole wall of the drilled hole, so that the telescopic rod 3 is not easy to fall into the karst cave and can bear objects with certain weight. Then put into the drilling with clay ball 7, telescopic link 3 withstands clay ball 7, prevents that falling membrane 71 can stop clay ball 7 and fall into the solution cavity from the clearance between telescopic link 3 after scattering, pushes pusher 8 into the drilling again, and under the action of gravity of pusher 8, pusher 8 can push away clay ball 7, makes clay ball 7 closely laminate with the pore wall of drilling to cut off the rivers passageway, reduce the erosion of rivers to the hole.

The embodiment of the application provides a hole sealing device for investigation of limestone area's implementation principle does: need carry out the hole sealing to reconnaissance drilling and handle, stretch into the trompil with the hole sealing frame earlier, make 3 reachs the assigned position backs of telescopic link, promote actuating lever 4 to the one side that is close to telescopic link 3 again, actuating lever 4 drives 3 extensions of telescopic link and the tip can insert in the drilling pore wall, then take out drilling with actuating lever 4 and propulsion pole 1 in proper order, put into drilling with clay ball 7 after that, make clay ball 7 fall on telescopic link 3, push into the drilling with impeller 8 again and make clay ball 7 pushed open and closely laminate with the drilling pore wall, carry out the grout to drilling at last and handle, thereby accomplish the hole sealing process.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. The utility model provides a hole sealing device is used in investigation of limestone area which characterized in that: including sealing hole frame, hole sealing ball, seal hole frame include push ram (1), can dismantle spliced pole (2) of connection on push ram (1) and set up a plurality of telescopic link (3) on spliced pole (2), the one end of telescopic link (3) is fixed on the circumference lateral wall of spliced pole (2), a plurality of the one end that spliced pole (2) were kept away from in telescopic link (3) is circumference around the axis of spliced pole (2) and distributes, self length direction extension or shortening can be followed in telescopic link (3), still be provided with the drive assembly who is used for driving telescopic link (3) extension or shortens on the frame of sealing hole.

2. The hole sealing device for the investigation borehole of the limestone area as claimed in claim 1, wherein: telescopic link (3) include removal sleeve pipe (31) that a plurality of slip caps in proper order established, drive assembly includes actuating lever (4) and can dismantle fixed column (5) of connection on actuating lever (4), actuating lever (4) and fixed column (5) all slide the cover and establish outside push rod (1), it is connected with tensile strip (51) to rotate on the circumference lateral wall of fixed column (5), the one end rotation connection of keeping away from actuating lever (4) of tensile strip (51) is on keeping away from removal sleeve pipe (31) of spliced pole (2) one end, the quantity of tensile strip (51) is the same with the quantity of telescopic link (3).

3. The hole sealing device for the investigation borehole of the limestone area as claimed in claim 2, wherein: one end of each movable sleeve (31) extending into the adjacent movable sleeve (31) is provided with a clamping table (311), and the other end of each movable sleeve (31) is provided with a limiting ring (312) for preventing the clamping table (311) of the adjacent movable sleeve (31) from dropping out of the movable sleeve.

4. The hole sealing device for the investigation borehole of the limestone area as claimed in claim 2, wherein: the anti-falling device is characterized in that one end of the driving rod (4) close to the fixing column (5) is fixedly connected with an anti-falling block (41), a fixing hole (52) for the driving rod (4) to extend into is formed in the fixing column (5), an anti-falling groove (521) for the anti-falling block (41) to be embedded is formed in the hole wall of the fixing hole (52), the anti-falling groove (521) comprises an embedding part (5211) and an anti-falling part (5212) which are communicated with each other, and the extending directions of the embedding part (5211) and the anti-falling part (5212) are different.

5. The hole sealing device for the investigation borehole of the limestone area as claimed in claim 1, wherein: one end fixedly connected with connecting block (11) that pushing ram (1) is close to spliced pole (2), set up mounting groove (21) that confession pushing ram (1) stretched into on spliced pole (2), set up spread groove (211) that confession connecting block (11) was embedded in on the cell wall of mounting groove (21), spread groove (211) are including the portion of stretching into (2111) and spacing portion (2112) that communicate each other, the extending direction who stretches into portion (2111) and spacing portion (2112) is different.

6. The hole sealing device for the investigation borehole of the limestone area as claimed in claim 1, wherein: and a positioning component for controlling the hole sealing depth is arranged on the push rod (1).

7. The hole sealing device for the investigation borehole of the limestone area as claimed in claim 6, wherein: locating component includes positioning disk (6), the external diameter of positioning disk (6) is greater than the drilling aperture, set up on positioning disk (6) and supply pushing ram (1) to slide locating hole (61) of wearing to establish, pushing ram (1) are worn out and are provided with location screw thread (12) on the circumference lateral wall of positioning disk (6) one end, the cover is equipped with positioning bolt (13) rather than self screw-thread fit on location screw thread (12), the one end fixedly connected with carriage release lever (42) of fixed column (5) are kept away from in actuating lever (4), set up on positioning disk (6) and supply carriage release lever (42) to slide removal hole (62) of wearing to establish.

8. The hole sealing device for the investigation borehole of the limestone area as claimed in claim 1, wherein: the hole sealing ball comprises a clay ball (7), and the diameter of the clay ball (7) is smaller than the aperture of the drilled hole.

9. The hole sealing device for the investigation borehole of the limestone area as claimed in claim 8, wherein: the outer layer of the clay ball (7) is wrapped by a layer of elastic anti-falling film (71), and one end, close to the pusher (8), of the anti-falling film (71) is provided with an opening.