A bottom expander for a punched bottom filling pile

Abstract

The application discloses a bottom-expanding device for punched bottom-expanded cast-in-place piles and relates to the technical field of punched bottom-expanded cast-in-place piles, which has the advantage that drill cuttings in a slag removal cylinder can be conveniently cleaned, and the technical scheme is as follows: the bottom-expanding device comprises a slag removal cylinder, a secondary shaft, a main shaft coaxially arranged at the bottom end of a drill rod, a first supporting rod and a second supporting rod which are hingedly connected, a sliding groove is formed in the lower end surface of the main shaft and used for sliding the outer wall of the upper end of the secondary shaft, the ends of the first supporting rod and the second supporting rod which are away from each other are hingedly connected with the circumferential side wall of the main shaft and the circumferential side wall of the secondary shaft respectively, a plurality of drill bits are fixed to the sides of the first supporting rod and the second supporting rod which are away from each other, the slot opening of the sliding groove is provided with a limiting piece for limiting the secondary shaft from moving out of the sliding groove, the slag removal cylinder is located below the secondary shaft, a square block is arranged at the bottom end of the secondary shaft and located in the slag removal cylinder, and the square block is detachably connected to the bottom end in the slag removal cylinder through a mounting piece.

Description

Technical Field

[0001] This invention relates to the field of bored pile technology, specifically to a device for expanding the base of a bored pile. Background Technology

[0002] An enlarged-base pile is a cast-in-place pile with a base diameter larger than the upper pile diameter. The bearing capacity of a single pile is significantly increased compared to the bearing capacity of the pile body diameter. Drilled enlarged-base cast-in-place piles are a relatively new construction method, representing an improvement and innovation of drilled cast-in-place piles. After drilling to reach the required bearing layer, a special drill bit is used at the pile end to enlarge the diameter of the pile end, thereby significantly increasing the ultimate bearing capacity of the pile compared to cast-in-place piles without an enlarged head.

[0003] Chinese Patent Publication No. CN201320487671.6 discloses a base-expanding device for perforated cast-in-place piles, comprising: a slag-cleaning cylinder, a baffle, a connecting pipe, a first rod, a second rod, a third rod, a fourth rod, a fifth rod, a sixth rod, a seventh rod, an eighth rod, a first bolt, a second bolt, a third bolt, a fourth bolt, a fifth bolt, a sixth bolt, a seventh bolt, an eighth bolt, a ninth bolt, a tenth bolt, a first guide groove, a second guide groove, a connecting rod, a rock crusher, and a rotating rod. The connection relationship is as follows: the upper end of the connecting pipe is threaded to the drill rod, and the lower end of the connecting pipe is connected to the first rod. The system consists of a single welded rod, with a hollow, internally inserted connecting tube. The first rod's two ends are connected to one end of the second, third, seventh, and eighth rods respectively using the first and second bolts. The other ends of the second, third, seventh, and eighth rods are placed in the first and second guide grooves respectively using the third and fifth bolts, and the fourth and seventh bolts. One end of the fourth and sixth rods is fixed to the fifth rod using the eighth and ninth bolts respectively. The connecting rod has a baffle plate, and its middle section is connected to the tenth bolt and the fifth rod respectively. The lower part of the connecting rod is welded to the bottom of the cleaning cylinder. When the drill rod drives the bottom-expanding device to rotate, the second, fourth, sixth, and seventh rods scrape away soil and expand the bottom. As the bottom-expanding work progresses, the drill cuttings scraped off by the second, fourth, sixth, and seventh rods are swept into the cleaning cylinder. The drill cuttings in the cleaning cylinder are then cleaned by lifting the drill rod.

[0004] The disadvantage of the above application is that when cleaning the drill cuttings in the cleaning tube by lifting the drill rod, the cleaning tube cannot be removed separately because it is welded to the lower part of the connecting rod. Therefore, it is necessary to manually remove the drill cuttings from the cleaning tube bit by bit, which is inconvenient. Therefore, the present invention provides a solution to solve the technical problem of the inconvenience of manually removing the drill cuttings from the cleaning tube bit by bit. Summary of the Invention

[0005] To address the aforementioned technical shortcomings, the purpose of this invention is to provide a bottom-expanding device for perforated cast-in-place piles, which has the advantage of facilitating the cleaning of drill cuttings inside the slag removal cylinder.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] This invention provides a base-expanding device for perforated cast-in-place piles, comprising a slag-cleaning cylinder, a secondary shaft, a main shaft coaxially disposed at the bottom end of a drill rod, and a first support rod and a second support rod hinged together. The lower end face of the main shaft has a groove into which the upper outer wall of the secondary shaft slides. The ends of the first and second support rods, which are far apart from each other, are hinged to the peripheral walls of the main shaft and the secondary shaft, respectively. Multiple drill bits are fixed to the opposite sides of the first and second support rods. The groove opening is provided with a limiting component to restrict the secondary shaft from moving out of the groove. The slag-cleaning cylinder is located below the secondary shaft, and the bottom end of the secondary shaft has a square block located inside the slag-cleaning cylinder. The square block is detachably connected to the bottom end of the slag-cleaning cylinder via an mounting component.

[0008] By adopting the above technical solution, the drill rod is lowered to allow the slag removal cylinder, auxiliary shaft, and main shaft to enter the borehole. When the bottom end of the slag removal cylinder abuts against the bottom plane of the borehole, the drill rod continues to lower and rotate. At this time, the drill rod drives the main shaft, auxiliary shaft, first support rod, and second support rod to rotate along the rotation axis of the main shaft, and the auxiliary shaft gradually slides into the groove on the main shaft. At this time, the first and second support rods gradually open, and the drill bits on the first and second support rods can continuously cut the surrounding hole wall to perform hole enlargement. As the drill bits on the first and second support rods continuously cut the surrounding hole wall, the cut drill slag... The cuttings fall into the cleaning cylinder. Once the cleaning cylinder is full, the drill rod is lifted to remove the cleaning cylinder, auxiliary shaft, and main shaft from the borehole. Then, the cleaning cylinder is removed using the mounting hardware. This allows for easy emptying of the drilling cuttings inside the cleaning cylinder, reducing the need for manual removal of the cuttings bit by bit. It facilitates cleaning of the drilling cuttings inside the cleaning cylinder. The limiting device ensures that the top of the auxiliary shaft is always within the groove, reducing the possibility of the auxiliary shaft sliding completely out of the groove due to gravity when the drill rod is lifted or lowered to allow the cleaning cylinder, auxiliary shaft, and main shaft to enter the borehole. It is simple and convenient to use.

[0009] Preferably, the bottom end of the secondary shaft is rotatably connected to the square block.

[0010] Preferably, the mounting component includes a square groove disposed at the bottom of the cleaning cylinder for vertical embedding of a square block, and grooves disposed on opposite sides of the square groove. A movable plate is horizontally slidably connected in both grooves. A slot is provided at the end of the square block near the groove. A rod is horizontally provided on the side of the movable plate away from the bottom of the groove, with one end inserted into the slot. A compression spring is provided between the bottom of the two grooves and the movable plate. A pusher is provided on the cleaning cylinder for simultaneously pushing the two movable plates to move away from each other.

[0011] Preferably, the pushing component includes a circular groove disposed at the bottom of the outer end of the slag cleaning cylinder. The bottom walls of the two grooves are provided with a connecting groove communicating with the circular groove. A turntable is rotatably connected to the bottom of the circular groove, and the bottom end of the turntable has two opposing arc-shaped grooves. The bottom ends of the two moving plates are vertically provided with push rods, and the bottom ends of the two push rods pass through the connecting grooves and are respectively located in the two arc-shaped grooves. The outer walls of the two push rods are in contact with the opposite side walls of the arc-shaped grooves. The slag cleaning cylinder is provided with a sealing component for sealing the opening of the circular groove.

[0012] Preferably, the closure includes a threaded barrel threaded into a circular groove, with the opening of the threaded barrel facing upwards, the turntable located inside the threaded barrel, the bottom end of the threaded barrel being flush with the bottom end of the slag cleaning cylinder, and the bottom end of the threaded barrel having two opposing rotating grooves.

[0013] Preferably, the top of the threaded barrel is provided with a first sealing gasket that abuts against the bottom of the circular groove, and a number of anti-slip ridges are evenly distributed along the circumference of the turntable on the side wall.

[0014] Preferably, the square block includes a first rectangular block and a second rectangular block. The first rectangular block is rotatably connected to the bottom end of the sub-shaft, and the second rectangular block is fixedly connected to the bottom end of the first rectangular block. The two slots are respectively disposed on opposite sides of the second rectangular block. The square groove includes a first rectangular groove and a second rectangular groove. The first rectangular groove and the second rectangular groove are connected. The first rectangular block is embedded in the first rectangular groove, and the bottom end of the first rectangular block is provided with a second sealing gasket that abuts against the bottom of the first rectangular groove. The second rectangular block is embedded in the second rectangular groove, and the two grooves are respectively disposed on opposite sides of the second rectangular groove.

[0015] Preferably, a circular scraper is placed inside the slag cleaning cylinder, and the top of the scraper has an installation groove for the square block and one end of the secondary shaft to pass through. The inner wall of the slag cleaning cylinder is in contact with the side wall of the scraper, the groove wall of the installation groove is in contact with the side wall of the secondary shaft, the bottom end of the scraper is in contact with the bottom of the slag cleaning cylinder, and two opposing pull rods are vertically provided at the top of the scraper, and the top of each pull rod is provided with a pull ring located outside the slag cleaning cylinder.

[0016] Preferably, the limiting member includes a circular sliding plate disposed at the top of the secondary shaft and located in the sliding groove, the groove wall of the sliding groove contacting the side wall of the sliding plate, and a retaining ring provided at the bottom end of the main shaft by bolts, the retaining ring being coaxially disposed with the sliding groove, the inner diameter of the retaining ring being smaller than the diameter of the sliding groove.

[0017] Preferably, the slag removal cylinder is made of stainless steel.

[0018] The beneficial effects of this invention are as follows: Lowering the drill rod allows the slag removal cylinder, auxiliary shaft, and main shaft to enter the borehole. When the bottom end of the slag removal cylinder abuts against the bottom plane of the borehole, the drill rod continues to lower and rotate. At this time, the drill rod drives the main shaft, auxiliary shaft, first support rod, and second support rod to rotate along the rotation axis of the main shaft, and the auxiliary shaft gradually slides into the groove on the main shaft. Simultaneously, the first and second support rods gradually open, allowing the drill bits on the first and second support rods to continuously cut the surrounding borehole walls, thus enlarging the hole. As the drill bits on the first and second support rods continuously cut the surrounding borehole walls, the cut-off drill slag... The cuttings fall into the cleaning cylinder. Once the cleaning cylinder is full, the drill rod is lifted to remove the cleaning cylinder, auxiliary shaft, and main shaft from the borehole. Then, the cleaning cylinder is removed using the mounting hardware. This allows for easy emptying of the drilling cuttings inside the cleaning cylinder, reducing the need for manual removal of the cuttings bit by bit. It facilitates cleaning of the drilling cuttings inside the cleaning cylinder. The limiting device ensures that the top of the auxiliary shaft is always within the groove, reducing the possibility of the auxiliary shaft sliding completely out of the groove due to gravity when the drill rod is lifted or lowered to allow the cleaning cylinder, auxiliary shaft, and main shaft to enter the borehole. It is simple and convenient to use. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the structure of this embodiment;

[0021] Figure 2 This is a schematic diagram illustrating the structure of the chute in this embodiment;

[0022] Figure 3 for Figure 2 Enlarged structural diagram of section A in the middle;

[0023] Figure 4 This is a schematic diagram illustrating the structure of the arc-shaped groove in this embodiment;

[0024] Figure 5 This is a schematic diagram illustrating the structure of the scraper in this embodiment.

[0025] Explanation of reference numerals in the attached figures:

[0026] In the diagram: 1. Slag removal cylinder; 2. Sub-shaft; 3. Drill rod; 4. Main shaft; 5. First support rod; 6. Second support rod; 7. Slide groove; 8. Drill bit; 9. Square block; 10. Square groove; 12. Groove; 13. Moving plate; 14. Slot; 15. Insert rod; 16. Compression spring; 17. Circular groove; 18. Connecting groove; 19. Turntable; 20. Arc groove; 21. Push rod; 22. Threaded barrel; 23. Rotating groove; 24. First sealing gasket; 25. Raised strip; 26. First rectangular block; 27. Second rectangular block; 28. First rectangular groove; 29. ​​Second rectangular groove; 30. Second sealing gasket; 31. Scraper; 32. Mounting groove; 33. Pull rod; 34. Pull ring; 35. Slide plate; 36. Retaining ring. Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] A base-expanding device for bored cast-in-place piles, such as Figure 1 and Figure 2 and Figure 3 The system includes a slag cleaning cylinder 1, a secondary shaft 2, a main shaft 4 coaxially mounted at the bottom of a drill rod 3, and a first support rod 5 and a second support rod 6 hinged together. The lower end face of the main shaft 4 has a groove 7 for the upper outer wall of the secondary shaft 2 to slide into. The ends of the first support rod 5 and the second support rod 6 that are far apart from each other are hinged to the peripheral side wall of the main shaft 4 and the peripheral side wall of the secondary shaft 2, respectively. Multiple drill bits 8 are fixed on the opposite side of the first support rod 5 and the second support rod 6. The groove opening of the groove 7 is provided with a limiting component to restrict the secondary shaft 2 from moving out of the groove 7. The slag cleaning cylinder 1 is located below the secondary shaft 2, and the bottom end of the secondary shaft 2 is provided with a square block 9 located inside the slag cleaning cylinder 1. The square block 9 is detachably connected to the bottom end of the slag cleaning cylinder 1 through an installation component.

[0029] like Figure 1 and Figure 2 and Figure 3The drill rod 3 is lowered so that the slag removal cylinder 1, the auxiliary shaft 2, and the main shaft 4 enter the borehole. When the bottom end of the slag removal cylinder 1 touches the bottom plane of the borehole, the drill rod 3 continues to lower and rotate. At this time, the drill rod 3 drives the main shaft 4, the auxiliary shaft 2, the first support rod 5, and the second support rod 6 to rotate along the rotation axis of the main shaft 4, and the auxiliary shaft 2 gradually slides into the groove 7 on the main shaft 4. At this time, the first support rod 5 and the second support rod 6 gradually open, and the drill bits 8 on the first support rod 5 and the second support rod 6 can continuously cut the surrounding hole wall to perform hole enlargement. As the drill bits 8 on the first support rod 5 and the second support rod 6 continuously cut the surrounding hole wall, the cut drill cuttings fall to the bottom. Inside the slag removal cylinder 1, once the slag removal cylinder 1 is full, the drill rod 3 is lifted to remove the slag removal cylinder 1, the auxiliary shaft 2, and the main shaft 4 from the borehole. Then, the slag removal cylinder 1 is removed using the mounting components. This makes it easy to empty the drill cuttings inside the slag removal cylinder 1, reducing the need for manual removal of the drill cuttings bit by bit. It facilitates the cleaning of the drill cuttings inside the slag removal cylinder 1. The limiting components ensure that the top of the auxiliary shaft 2 is always within the slide groove 7, reducing the possibility that the auxiliary shaft 2 might completely slide out of the slide groove 7 due to gravity when the drill rod 3 is lifted or lowered to allow the slag removal cylinder 1, auxiliary shaft 2, and main shaft 4 to enter the borehole. It is simple and convenient to use.

[0030] like Figure 3 The bottom end of the secondary shaft 2 is rotatably connected to the square block 9. The purpose of this setting is that when the bottom end of the cleaning cylinder 1 is against the bottom plane of the borehole and the drill rod 3 continues to descend and rotate, the secondary shaft 2 will not drive the square block 9 and the cleaning cylinder 1 to rotate because the bottom end of the secondary shaft 2 is rotatably connected to the square block 9. At this time, the cleaning cylinder 1 can be reduced from rotating with the secondary shaft 2, which would cause wear on the cleaning cylinder 1. It is simple and convenient to use.

[0031] like Figure 3 The installation components include a square groove 10 located at the bottom of the cleaning cylinder 1 for vertical insertion of a square block 9, and grooves 12 located on opposite sides of the square groove 10. A movable plate 13 is horizontally slidably connected to each of the two grooves 12. A slot 14 is provided at the end of each square block 9 near the groove 12. A rod 15, with one end inserted into the slot 14, is horizontally provided on the side of the movable plate 13 facing away from the bottom of the groove 12. A compression spring 16 is provided between the bottom of each groove 12 and the movable plate 13. A pusher is provided on the cleaning cylinder 1 to simultaneously push the two movable plates 13 in a direction away from each other. This design aims to simultaneously push the two movable plates 13 in a direction away from each other, compressing the compression spring 16 until the rod 15 is completely removed from the slot 14. At this point, the cleaning cylinder 1 can be removed separately, making disassembly and assembly simple and convenient.

[0032] like Figure 3 and Figure 4The pushing component includes a circular groove 17 located at the bottom of the slag cleaning cylinder 1. The bottom walls of the two grooves 12 are provided with connecting grooves 18 that communicate with the circular groove 17. A turntable 19 is rotatably connected to the bottom of the circular groove 17, and two opposing arc-shaped grooves 20 are opened at the bottom of the turntable 19. Push rods 21 are vertically provided at the bottom of the two moving plates 13, and the bottom ends of the two push rods 21 pass through the connecting grooves 18 and are located in the two arc-shaped grooves 20 respectively. The outer walls of the two push rods 21 are in contact with the opposite side walls of the arc-shaped grooves 20. The slag cleaning cylinder 1 is provided with a sealing component for closing the opening of the circular groove 17. The purpose of this setting is that when it is necessary to push the two moving plates 13 to move away from each other at the same time, it is only necessary to release the sealing component from the opening of the circular groove 17, and then manually rotate the turntable 19. At this time, the two moving plates 13 can be pushed to move away from each other at the same time through the cooperation of the two arc-shaped grooves 20 on the turntable 19 and the push rods 21 on the two moving plates 13. It is simple and convenient to use.

[0033] like Figure 3 and Figure 4 The sealing component includes a threaded barrel 22 threadedly connected to a circular groove 17, with the opening of the threaded barrel 22 facing upwards. A turntable 19 is located inside the threaded barrel 22, and the bottom end of the threaded barrel 22 is flush with the bottom end of the cleaning cylinder 1. The bottom end of the threaded barrel 22 is provided with two opposing rotating grooves 23. The purpose of this arrangement is to seal the opening of the circular groove 17 through the threaded barrel 22. At this time, the threaded barrel 22 can reduce the occurrence of soil from the bottom surface of the drill hole entering the circular groove 17 when the bottom end of the cleaning cylinder 1 is pressed against the bottom surface of the drill hole. When it is necessary to release the seal on the opening of the circular groove 17, simply unscrew the threaded groove to separate it from the circular groove 17. At this time, the seal on the opening of the circular groove 17 can be released. The threaded barrel 22 can be easily rotated manually through the two rotating grooves 23, making it simple and convenient to use.

[0034] like Figure 3 The top of the threaded barrel 22 is provided with a first sealing gasket 24 that abuts against the bottom of the circular groove 17. Several anti-slip ridges 25 are evenly distributed along the circumference of the turntable 19 on the side wall of the turntable 19. The purpose of this setting is to facilitate the sealing of the gap between the top of the threaded barrel 22 and the bottom of the circular groove 17 through the first sealing gasket 24. At this time, the moisture or water in the borehole can be reduced from entering the threaded barrel 22 through the gap between the top of the threaded barrel 22 and the bottom of the circular groove 17, thus reducing the occurrence of corrosion of the turntable 19 and the push rod 21. It is simple and convenient to use.

[0035] like Figure 3The square block 9 includes a first rectangular block 26 and a second rectangular block 27. The first rectangular block 26 is rotatably connected to the bottom end of the sub-shaft 2, and the second rectangular block 27 is fixedly connected to the bottom end of the first rectangular block 26. Two slots 14 are respectively provided on opposite sides of the second rectangular block 27. The square groove 10 includes a first rectangular groove 28 and a second rectangular groove 29. The first rectangular groove 28 and the second rectangular groove 29 communicate with each other. The first rectangular block 26 is embedded in the first rectangular groove 28, and the bottom end of the first rectangular block 26 is provided with a second sealing gasket 30 that abuts against the bottom of the first rectangular groove 28. The second rectangular block 27 is embedded in the second rectangular groove 28. Inside the two rectangular grooves 29, two recesses 12 are respectively set on opposite sides of the second rectangular groove 29. The purpose of this setting is to seal the gap between the bottom end of the first rectangular block 26 and the bottom of the first rectangular groove 28 through the second sealing gasket 30. At this time, the moisture or water in the slag cleaning cylinder 1 can be reduced from entering the recesses 12 or slots 14 through the gap between the bottom end of the first rectangular block 26 and the bottom of the first rectangular groove 28 and the gap between the side wall of the second rectangular block 27 and the wall of the second rectangular groove 29, thus reducing the occurrence of corrosion of the moving plate 13, compression spring 16, and insertion rod 15. It is simple and convenient to use.

[0036] like Figure 2 and Figure 3 and Figure 5 A circular scraper 31 is placed inside the slag cleaning cylinder 1. The top of the scraper 31 has an installation groove 32 for the square block 9 and one end of the auxiliary shaft 2 to pass through. The inner wall of the slag cleaning cylinder 1 contacts the side wall of the scraper 31, the groove wall of the installation groove 32 contacts the side wall of the auxiliary shaft 2, and the bottom end of the scraper 31 contacts the bottom of the slag cleaning cylinder 1. Two opposing pull rods 33 are vertically mounted on the top of the scraper 31, and each pull rod 33 has a pull ring 34 located outside the slag cleaning cylinder 1 at its top. The slag cleaning cylinder 1 is made of stainless steel. This design is intended to allow for easy removal of the slag cleaning cylinder. When the cuttings in the cleaning cylinder 1 are poured out, the scraper 31 will follow the cuttings out of the cleaning cylinder 1. At this time, the cuttings adhering to the inner wall of the cleaning cylinder 1 can be scraped off by the scraper 31. Alternatively, without removing the cleaning cylinder 1, the pull ring 34 can be manually pulled to move the pull rod 33 and the scraper 31 vertically upward. At this time, the cuttings in the cleaning cylinder 1 can be pushed out by the scraper 31, thereby reducing the need to manually remove the cuttings in the cleaning cylinder 1 bit by bit. This makes it easier to clean the cuttings in the cleaning cylinder 1 and is simple and convenient to use.

[0037] like Figure 2The limiting component includes a circular sliding plate 35 located at the top of the secondary shaft 2 and within the slide groove 7. The groove wall of the slide groove 7 contacts the side wall of the sliding plate 35. A retaining ring 36 is bolted to the bottom of the main shaft 4, and the retaining ring 36 is coaxially arranged with the slide groove 7. The inner diameter of the retaining ring 36 is smaller than the diameter of the slide groove 7. The purpose of this arrangement is that when the secondary shaft 2 gradually slides out of the slide groove 7, the secondary shaft 2 will drive the sliding plate 35 to gradually approach the retaining ring 36. Because the inner diameter of the retaining ring 36 is smaller than the diameter of the slide groove 7, the groove wall of the slide groove 7 contacts the side wall of the sliding plate 35. Therefore, when the bottom end of the sliding plate 35 contacts the top end of the retaining ring 36, this is the farthest distance that the secondary shaft 2 has slid out of the slide groove 7. This design is simple and convenient to use.

[0038] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A base-expanding device for bored cast-in-place piles, characterized in that, The system includes a slag cleaning cylinder (1), a secondary shaft (2), a main shaft (4) coaxially disposed at the bottom end of a drill rod (3), a first support rod (5) and a second support rod (6) hinged together. The lower end face of the main shaft (4) is provided with a groove (7) for the upper outer wall of the secondary shaft (2) to slide into. The ends of the first support rod (5) and the second support rod (6) that are far apart from each other are respectively hinged to the peripheral side wall of the main shaft (4) and the peripheral side wall of the secondary shaft (2). Multiple drill bits (8) are fixed on the opposite side of the first support rod (5) and the second support rod (6). The groove opening of the groove (7) is provided with a limiting member to restrict the secondary shaft (2) from moving out of the groove (7). The slag cleaning cylinder (1) is located below the secondary shaft (2), and the bottom end of the secondary shaft (2) is provided with a square block (9) located inside the slag cleaning cylinder (1). The square block (9) is detachably connected to the bottom end of the slag cleaning cylinder (1) through an installation member. The bottom end of the sub-shaft (2) is rotatably connected to the square block (9); The mounting components include a square groove (10) set at the bottom of the cleaning cylinder (1) for vertical embedding of a square block (9) and grooves (12) set on opposite sides of the square groove (10). A movable plate (13) is horizontally slidably connected in both grooves (12). A slot (14) is provided at the end of the square block (9) near the groove (12). A rod (15) with one end inserted into the slot (14) is horizontally provided on the side of the movable plate (13) away from the bottom of the groove (12). A compression spring (16) is provided between the bottom of the two grooves (12) and the movable plate (13). A pusher is provided on the cleaning cylinder (1) for simultaneously pushing the two movable plates (13) to move away from each other. A circular scraper (31) is placed inside the slag cleaning cylinder (1), and the top of the scraper (31) is provided with an installation groove (32) for the square block (9) and one end of the secondary shaft (2) to pass through. The inner wall of the slag cleaning cylinder (1) is in contact with the side wall of the scraper (31), the groove wall of the installation groove (32) is in contact with the side wall of the secondary shaft (2), the bottom end of the scraper (31) is in contact with the bottom of the slag cleaning cylinder (1), and two opposing pull rods (33) are vertically provided at the top of the scraper (31), and the top of each of the two pull rods (33) is provided with a pull ring (34) located outside the slag cleaning cylinder (1).

2. The base-expanding device for a perforated cast-in-place pile as described in claim 1, characterized in that, The pusher includes a circular groove (17) at the bottom of the slag cleaning cylinder (1). The bottom walls of the two grooves (12) are provided with a connecting groove (18) that communicates with the circular groove (17). The bottom of the circular groove (17) is rotatably connected to a turntable (19), and the bottom of the turntable (19) has two opposing arc grooves (20). The bottom of the two moving plates (13) is provided with push rods (21) vertically, and the bottom of the two push rods (21) passes through the connecting groove (18) and is located in the two arc grooves (20) respectively. The outer walls of the two push rods (21) are in contact with the opposite side walls of the arc grooves (20). The slag cleaning cylinder (1) is provided with a sealing member for closing the opening of the circular groove (17).

3. The base-expanding device for a perforated cast-in-place pile as described in claim 2, characterized in that, The closure includes a threaded barrel (22) threaded into a circular groove (17), with the opening of the threaded barrel (22) facing upwards. The turntable (19) is located inside the threaded barrel (22). The bottom end of the threaded barrel (22) is flush with the bottom end of the slag cleaning cylinder (1). The bottom end of the threaded barrel (22) is provided with two opposing rotating grooves (23).

4. The base-expanding device for a perforated cast-in-place pile as described in claim 3, characterized in that, The top of the threaded barrel (22) is provided with a first sealing gasket (24) that abuts against the bottom of the circular groove (17), and a number of anti-slip ridges (25) are evenly distributed along the circumference of the turntable (19) on the side wall of the turntable (19).

5. The base-expanding device for a perforated cast-in-place pile as described in claim 1, characterized in that, The square block (9) includes a first rectangular block (26) and a second rectangular block (27). The first rectangular block (26) is rotatably connected to the bottom end of the sub-shaft (2). The second rectangular block (27) is fixedly connected to the bottom end of the first rectangular block (26). The two slots (14) are respectively located on opposite sides of the second rectangular block (27). The square groove (10) includes a first rectangular groove (28) and a second rectangular groove (29). The first rectangular groove (28) and the second rectangular groove (29) are connected. The first rectangular block (26) is embedded in the first rectangular groove (28). The bottom end of the first rectangular block (26) is provided with a second sealing gasket (30) that abuts against the bottom of the first rectangular groove (28). The second rectangular block (27) is embedded in the second rectangular groove (29). The two grooves (12) are respectively located on opposite sides of the second rectangular groove (29).

6. The base-expanding device for a perforated cast-in-place pile as described in claim 1, characterized in that, The limiting component includes a circular slide plate (35) disposed at the top of the secondary shaft (2) and located in the slide groove (7). The groove wall of the slide groove (7) contacts the side wall of the slide plate (35). The bottom end of the main shaft (4) is provided with a retaining ring (36) by bolts. The retaining ring (36) is coaxially disposed with the slide groove (7). The inner diameter of the retaining ring (36) is smaller than the diameter of the slide groove (7).

7. The base-expanding device for a perforated cast-in-place pile as described in claim 6, characterized in that, The slag cleaning cylinder (1) is made of stainless steel.

Images