Square pile hole rotary drilling equipment and use method thereof

Abstract

A square pile hole rotary drilling device and its use method. The device adopts a structural form different from traditional hole-forming equipment, including a power mechanism, a transmission mechanism, and an excavation mechanism. The transmission mechanism is connected to a hydraulic lifting mechanism on a pile driver column. The power mechanism is arranged at the power input end of the transmission mechanism. The excavation mechanism is arranged at the power output end of the transmission mechanism, and square pile holes are prepared by the excavation mechanism. The device of the present invention eliminates the restrictive structure of the square frame, reduces the space occupied by the device, and effectively improves flexibility. The device drill rod not only provides torque to the drill bit, but also provides downward pressure to the drill bit through the hydraulic lifting mechanism on the pile driver column and the device drill rod. During use, the drilling speed is greatly improved, and the constraint that the length of the drill bit of the traditional square hole drill must be greater than the target pile hole length is broken away. The device has the characteristics of wide application range, strong operability, large power output, and high efficiency, and effectively meets the process requirements of square pile hole rotary drilling.

Description

Technical Field

[0001] The invention belongs to the technical field of concrete cast-in-place pile hole excavation, and in particular relates to a square pile hole rotary excavation device and a use method thereof. Background Art

[0002] At present, concrete cast-in-place piles can be classified into round piles and square piles according to the cross-sectional shape of the pile body. Although round piles are the most common, square piles have a larger lateral surface area than round piles when the cross-sectional area is the same, so that the pile body can obtain greater lateral friction resistance underground, thereby effectively improving the bearing capacity of a single pile. In addition, square piles have better shear resistance and seismic performance.

[0003] However, in the construction of concrete cast-in-place pile foundation projects, pile holes are usually prepared by rotary drilling, so it is easiest to prepare circular pile holes. However, if square piles are used, they are usually prepared by manual excavation, which has the disadvantages of low excavation efficiency, long excavation cycle and high operation risk.

[0004] To this end, Chinese patent application number 202021692933.9 discloses an anti-slip pile square hole drilling device, which uses a square frame the same size as the target hole as a limit and uses a Leroy triangular drill bit to drill the pile hole within the limit. However, this drilling device has the disadvantages of taking up a lot of space and poor flexibility. In addition, the drilling device does not have a downward drilling pressure, which slows the drilling speed. At the same time, it also requires that the drill bit length must be greater than the length of the target pile hole. As a result, the depth of the target pile hole is completely limited by the drill bit length, which affects the scope of application of the drilling device. Summary of the Invention

[0005] In response to the problems existing in the prior art, the present invention provides a square pile hole rotary drilling device and a method for using the same, which adopts a structural form different from traditional hole-forming equipment, eliminates the restrictive structure of the square frame, greatly reduces the space occupied by the equipment, and effectively improves flexibility. The drill rod of the equipment not only provides torque for the drill bit, but also provides downward pressure on the drill bit through the hydraulic lifting mechanism on the pile driver column and the drill rod of the equipment, thereby greatly improving the drilling speed and getting rid of the constraint that the length of the drill bit of the traditional square hole drill must be greater than the length of the target pile hole. The present invention has the characteristics of wide application range, strong operability, large power output and high efficiency, and effectively meets the process requirements of rotary drilling of square pile holes.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solution: a square pile hole rotary drilling device, including a power mechanism, a transmission mechanism and an excavation mechanism; the transmission mechanism is connected to the hydraulic lifting mechanism on the pile driver column; the power mechanism is arranged at the power input end of the transmission mechanism; the excavation mechanism is arranged at the power output end of the transmission mechanism, and the square pile hole is prepared by the excavation mechanism.

[0007] The power mechanism adopts an electric drive gear transmission structure, and the power output end of the power mechanism is a gear set.

[0008] The transmission mechanism includes a gear, a gear ring, a solid drill rod, a hollow drill rod and an adapter bracket; one end of the adapter bracket is connected to the hydraulic lifting mechanism on the pile driver column, and the adapter bracket can slide up and down along the pile driver column; the hollow drill rod is vertically arranged at the other end of the adapter bracket; the gear ring is concentrically fixed on the top of the hollow drill rod, and an internal thread is provided on the inner surface of the bottom end of the hollow drill rod; the solid drill rod is concentrically arranged inside the hollow drill rod, and the gear is concentrically fixed on the top of the solid drill rod and is located above the gear ring; the solid drill rod and the hollow drill rod are rotatably connected through a first bearing; the hollow drill rod and the adapter bracket are rotatably connected through a second bearing; a first adapter flange is fixed at the bottom end of the solid drill rod; the power mechanism meshes with the gear and the gear ring through the gear set at its power output end.

[0009] The gear and the ring gear rotate in opposite directions, and the speed ratio between the gear and the ring gear is 1:3.

[0010] The excavation mechanism includes a transmission shaft, a hollow drill bit and an adapter sleeve; the cross-sectional shape of the hollow drill bit is a Lerow triangle; the transmission shaft is vertically fixed at the centroid of the top plate of the hollow drill bit, and a reinforcing rib is fixed between the transmission shaft and the top plate of the hollow drill bit. A second adapter flange is fixed at the top of the transmission shaft, and the second adapter flange at the top of the transmission shaft is transmission-connected to the first adapter flange at the bottom end of the solid drill rod through a universal joint; the transmission shaft and the solid drill rod are eccentrically distributed; the adapter sleeve is eccentrically sleeved on the outside of the transmission shaft, and the adapter sleeve and the transmission shaft are rotationally connected through a third bearing; an external thread is provided on the outer surface of the adapter sleeve, and the hollow drill rod and the adapter sleeve are coaxially screwed and fixed together.

[0011] The eccentricity between the adapter sleeve and the transmission shaft is the distance between any two vertices of the Reloj triangle of the hollow drill bit cross section. times.

[0012] A stationary cutter disc is provided at the bottom of the hollow drill bit, and the shape of the stationary cutter disc is a Reuleaux triangle. One of the Reuleaux triangle sides of the stationary cutter disc is hinged to the hollow drill bit by a hinge, and the hinge position of the hinge is located in the middle of the Reuleaux triangle side; a clip is provided between the other two Reuleaux triangle sides of the stationary cutter disc and the hollow drill bit, and the installation position of the clip is located in the middle of the Reuleaux triangle side.

[0013] There are three fan-shaped hollow holes distributed along the circumference on the stationary cutter disc, and static teeth are fixed at the vertices of the Lelo triangle of the stationary cutter disc; a movable cutter disc is axially hinged at the bottom center of the stationary cutter disc, and the movable cutter disc adopts a fan-shaped three-blade structure, and movable teeth are fixed on the blades of the movable cutter disc; the size of the fan-shaped blades of the movable cutter disc is equal to the size of the fan-shaped hollow holes on the stationary cutter disc.

[0014] A docking, blocking, and positioning block structure is provided between the stationary teeth and the movable teeth, and the rotation angle range of the movable cutter disc is limited by the docking, blocking, and positioning block structure.

[0015] A method for using a square pile hole rotary drilling device, specifically comprising:

[0016] When a square pile hole needs to be prepared, the pile driver is first moved to the drilling position so that the square pile hole rotary drilling equipment is located directly above the square pile hole calibration point. Then the power mechanism is started, and the gear set at its power output end transmits power to the gear and ring gear of the transmission mechanism respectively. At this time, the gear and ring gear rotate in opposite directions, and the speed ratio of the gear and ring gear is 1:3;

[0017] When the gear rotates at a set speed, it drives the hollow drill bit to rotate in sequence through the solid drill rod, universal joint, and drive shaft. At the same time, when the ring gear rotates at a specific speed, it drives the adapter sleeve to rotate synchronously through the hollow drill rod, and then drives the drive shaft and hollow drill bit to revolve around the center of the adapter sleeve through the adapter sleeve. At this time, the speed ratio of the hollow drill bit's rotation and revolution is 1:3, and the directions are opposite. The motion trajectory of the vertices of the Reuleaux triangle in the cross section of the hollow drill bit forms a square.

[0018] When the hollow drill bit rotates according to the set speed and motion trajectory, the adapter bracket is controlled to slide downward at a uniform speed along the pile driver column until the movable cutter disc at the bottom of the hollow drill bit first touches the ground. When the movable cutter disc touches the ground, the movement of the movable cutter disc is blocked by the resistance, and the static cutter disc continues to rotate with the hollow drill bit until the movable teeth on the movable cutter disc and the static teeth on the static cutter disc are completely stuck at the docking stop positioning block structure. At this time, the movable cutter disc and the static cutter disc remain relatively stationary, and the fan-shaped hollow holes on the static cutter disc are completely exposed;

[0019] As the hollow drill bit rotates and the adapter bracket slides down at a constant speed along the pile driver column, the hollow drill bit gradually screws into the ground. At the same time, as the hollow drill bit continues to screw in, the soil in the ground enters the hollow drill bit through the fan-shaped hollow holes for temporary storage.

[0020] When the soil inside the hollow drill bit is full, the rotation of the hollow drill bit is first paused, and then the power mechanism is started in the reverse direction to make the hollow drill bit rotate in the reverse direction. Under the action of resistance, the movement of the movable cutter disc is blocked again, and the stationary cutter disc continues to rotate with the hollow drill bit until the static teeth on the movable cutter disc and the stationary cutter disc are completely stuck at the docking stop and positioning block structure. At this time, the movable cutter disc and the stationary cutter disc remain relatively stationary, and the movable cutter disc completely blocks the fan-shaped hollow hole.

[0021] When the fan-shaped hollow hole is completely blocked and closed by the moving cutterhead, the rotation of the hollow drill bit is stopped. Then the adapter bracket is controlled to slide upward at a constant speed along the pile driver column until the hollow drill bit is completely removed from the pile hole. Then the pile driver is adjusted to rotate the hollow drill bit to the ground above the pile hole. Then the buckle is opened, and the static cutterhead flips downward around the hinge under the action of gravity, causing the soil stored in the hollow drill bit to tilt out, thus completing the soil discharge operation.

[0022] When the soil discharge operation is completed, the static cutterhead is flipped upward to a horizontal state and locked with a buckle. Then the pile driver is adjusted to turn the hollow drill bit to the top of the pile hole again, and then the hollow drill bit is sent back to the bottom of the pile hole to continue the drilling operation; and so on, until the preparation of the square pile hole of the set depth is completed.

[0023] Beneficial effects of the present invention:

[0024] The square pile hole rotary drilling equipment and the use method thereof of the present invention adopt a structural form different from traditional hole-forming equipment, eliminate the restrictive structure of the square frame, greatly reduce the space occupied by the equipment, and effectively improve the flexibility. The drill rod of the equipment not only provides torque for the drill bit, but also provides downward pressure on the drill bit through the hydraulic lifting mechanism on the pile driver column and the drill rod of the equipment, thereby greatly improving the drilling speed, getting rid of the constraint that the length of the drill bit of the traditional square hole drill must be greater than the length of the target pile hole, so that the present invention has the characteristics of wide application range, strong operability, large power output and high efficiency, and effectively meets the process requirements of square pile hole rotary drilling. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the transmission mechanism structure of the square pile hole rotary drilling equipment of the present invention;

[0026] Figure 2 A schematic diagram (cross-sectional view) of the transmission mechanism structure of the square pile hole rotary drilling equipment of the present invention;

[0027] Figure 3 This is a schematic structural diagram of the excavation mechanism of the square pile hole rotary drilling equipment of the present invention;

[0028] Figure 4 Schematic diagram of the static cutterhead structure of the excavation mechanism of the square pile hole rotary drilling equipment of the present invention;

[0029] Figure 5 Schematic diagram of the movable cutterhead structure of the excavation mechanism of the square pile hole rotary drilling equipment of the present invention;

[0030] Figure 6 This is a schematic diagram of the structure of the assembled static cutterhead and dynamic cutterhead of the excavation mechanism of the square pile hole rotary drilling equipment of the present invention (the static teeth and the dynamic teeth are butted together and the fan-shaped hollow holes are not blocked by the dynamic cutterhead);

[0031] Figure 7 This is a schematic diagram of the structure of the excavation mechanism of the square pile hole rotary drilling equipment of the present invention after the static cutterhead and the dynamic cutterhead are assembled (the static teeth and the dynamic teeth are separated from each other and the fan-shaped hollow hole is completely blocked by the passive cutterhead);

[0032] Figure 8 A schematic diagram of the partial structure of the square pile hole rotary drilling equipment of the present invention (including a hollow drill bit, a stationary cutterhead, a movable cutterhead and a buckle);

[0033] Figure 9 A schematic diagram of the movement trajectory of the vertices of the Reuleaux triangle of the hollow drill bit of the square pile hole rotary drilling equipment of the present invention;

[0034] In the figure, 1 is a gear, 2 is a gear ring, 3 is a solid drill rod, 4 is a hollow drill rod, 5 is an adapter bracket, 6 is a first bearing, 7 is a second bearing, 8 is a first adapter flange, 9 is a transmission shaft, 10 is a hollow drill bit, 11 is an adapter sleeve, 12 is a stationary cutter head, 13 is a buckle, 14 is a fan-shaped hollow hole, 15 is a stationary tooth, 16 is a moving cutter head, 17 is a moving tooth, 18 is a docking stop and positioning block structure, 19 is a reinforcing rib, 20 is a third bearing, 21 is a second adapter flange, and 22 is a hinge. DETAILED DESCRIPTION

[0035] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] like Figures 1 to 8 As shown, a square pile hole rotary drilling device includes a power mechanism, a transmission mechanism and an excavation mechanism; the transmission mechanism is connected to the hydraulic lifting mechanism on the pile driver column; the power mechanism is arranged at the power input end of the transmission mechanism; the excavation mechanism is arranged at the power output end of the transmission mechanism, and the square pile hole is prepared by the excavation mechanism.

[0037] The power mechanism adopts an electric drive gear transmission structure, and the power output end of the power mechanism is a gear set with a specific speed.

[0038] The transmission mechanism includes a gear 1, a ring gear 2, a solid drill rod 3, a hollow drill rod 4 and an adapter bracket 5; one end of the adapter bracket 5 is connected to the hydraulic lifting mechanism on the pile driver column, and the adapter bracket 5 can slide up and down along the pile driver column; the hollow drill rod 4 is vertically arranged at the other end of the adapter bracket 5; the ring gear 2 is concentrically fixed on the top of the hollow drill rod 4, and an internal thread is provided on the inner surface of the bottom end of the hollow drill rod 4; the solid drill rod 3 is concentrically arranged inside the hollow drill rod 4, and the gear 1 is concentrically fixed on the top of the solid drill rod 3 and is located above the ring gear 2; the solid drill rod 3 and the hollow drill rod 4 are rotatably connected by a first bearing 6; the hollow drill rod 4 and the adapter bracket 5 are rotatably connected by a second bearing 7; a first adapter flange 8 is fixed at the bottom end of the solid drill rod 3; the power mechanism is meshed with the gear 1 and the ring gear 2 through the gear set at its power output end.

[0039] The gear 1 and the ring gear 2 rotate in opposite directions, and the speed ratio between the gear 1 and the ring gear 2 is 1:3.

[0040] The excavation mechanism includes a transmission shaft 9, a hollow drill bit 10 and an adapter sleeve 11; the cross-sectional shape of the hollow drill bit 10 is a Leroy triangle; the transmission shaft 9 is vertically fixed at the centroid of the top plate of the hollow drill bit 10, and a reinforcing rib 19 is fixed between the transmission shaft 9 and the top plate of the hollow drill bit 10, and a second adapter flange 21 is fixed at the top of the transmission shaft 9. The second adapter flange 21 at the top of the transmission shaft 9 is transmission-connected to the first adapter flange 8 at the bottom end of the solid drill rod 3 through a universal joint; the transmission shaft 9 and the solid drill rod 3 are eccentrically distributed; the adapter sleeve 11 is eccentrically sleeved on the outside of the transmission shaft 9, and the adapter sleeve 11 and the transmission shaft 9 are rotationally connected through a third bearing 20; an external thread is provided on the outer surface of the adapter sleeve 11, and the hollow drill rod 4 and the adapter sleeve 11 are coaxially screwed and fixed together.

[0041] The eccentricity between the adapter sleeve 11 and the transmission shaft 9 is the distance between any two vertices of the Reuleaux triangle in the cross section of the hollow drill bit 10. times.

[0042] A stationary cutter disc 12 is provided at the bottom of the hollow drill bit 10. The stationary cutter disc 12 is in the shape of a Reuleaux triangle. One of the Reuleaux triangle sides of the stationary cutter disc 12 is hinged to the hollow drill bit 10 through a hinge 22, and the hinge position of the hinge 22 is located in the middle of the Reuleaux triangle side; a clip 13 is provided between the other two Reuleaux triangle sides of the stationary cutter disc 12 and the hollow drill bit 10, and the installation position of the clip 13 is located in the middle of the Reuleaux triangle side.

[0043] There are three fan-shaped hollow holes 14 distributed along the circumferential direction on the static cutter disc 12, and static teeth 15 are fixedly provided at the vertices of the Reault triangle of the static cutter disc 12; a movable cutter disc 16 is axially hinged at the bottom center of the static cutter disc 12, and the movable cutter disc 16 adopts a fan-shaped three-blade structure, and movable teeth 17 are fixedly provided on the blades of the movable cutter disc 16; the size of the fan-shaped blades of the movable cutter disc 16 is equal to the size of the fan-shaped hollow holes 14 on the static cutter disc 12.

[0044] A docking, blocking, and positioning block structure 18 is provided between the stationary teeth 15 and the movable teeth 17 , and the rotation angle range of the movable cutter head 16 is limited by the docking, blocking, and positioning block structure 18 .

[0045] A method for using a square pile hole rotary drilling device, specifically comprising:

[0046] When it is necessary to prepare a square pile hole, the pile driver is first moved to the drilling position so that the square pile hole rotary drilling device of the present invention is located directly above the square pile hole calibration point. Then, the power mechanism is started, and the gear set at its power output end transmits power to the gear 1 and the ring gear 2 of the transmission mechanism respectively. At this time, the rotation directions of the gear 1 and the ring gear 2 are opposite, and the speed ratio of the gear 1 to the ring gear 2 is 1:3.

[0047] When the gear 1 rotates at a set speed, it drives the hollow drill bit 10 to rotate through the solid drill rod 3, the universal joint and the transmission shaft 9. At the same time, when the ring gear 2 rotates at a specific speed, it drives the adapter sleeve 11 to rotate synchronously through the hollow drill rod 4, and then drives the transmission shaft 9 and the hollow drill bit 10 to revolve around the center of the adapter sleeve 11 through the adapter sleeve 11. At this time, the speed ratio of the hollow drill bit 10's rotation to revolution is 1:3 and the directions are opposite. Figure 9 As shown, the movement trajectory of the vertices of the Reuleaux triangle of the cross section of the hollow drill bit 10 can just form a square.

[0048] When the hollow drill bit 10 rotates according to the set speed and motion trajectory, the adapter bracket 5 is controlled to slide downward at a uniform speed along the pile driver column until the movable cutter disc 16 at the bottom of the hollow drill bit 10 first touches the ground. When the movable cutter disc 16 touches the ground, the movement of the movable cutter disc 16 is blocked by the action of resistance, and the stationary cutter disc 12 continues to rotate with the hollow drill bit 10 until the movable teeth 17 on the movable cutter disc 16 and the stationary teeth 15 on the stationary cutter disc 12 are completely stuck at the docking blocking positioning block structure 18. At this time, the movable cutter disc 16 and the stationary cutter disc 12 remain relatively stationary, and the fan-shaped hollow holes 14 on the stationary cutter disc 12 are completely exposed.

[0049] As the hollow drill bit 10 rotates and the adapter bracket 5 slides downward at a uniform speed along the pile driver column, the hollow drill bit 10 gradually screws into the ground. At the same time, as the hollow drill bit 10 continues to be screwed in, the soil in the ground enters the hollow drill bit 10 through the fan-shaped hollow holes 14 for temporary storage.

[0050] When the soil inside the hollow drill bit 10 is fully stored, the rotation of the hollow drill bit 10 is first paused, and then the power mechanism is started in reverse to make the hollow drill bit 10 rotate in the reverse direction. Under the action of resistance, the movement of the movable cutter disc 16 is blocked again, and the stationary cutter disc 12 continues to rotate with the hollow drill bit 10 until the movable cutter disc 16 and the stationary teeth 15 on the stationary cutter disc 12 are completely stuck at the docking blocking and positioning block structure 18. At this time, the movable cutter disc 16 and the stationary cutter disc 12 remain relatively stationary, and the movable cutter disc 16 completely blocks the fan-shaped hollow hole 14.

[0051] After the fan-shaped hollow hole 14 is completely blocked and closed by the movable cutter head 16, the rotation of the hollow drill bit 10 is suspended, and then the adapter bracket 5 is controlled to slide upward at a uniform speed along the pile driver column until the hollow drill bit 10 is completely removed from the pile hole. The pile driver is then adjusted to rotate the hollow drill bit 10 to the ground above the pile hole. The buckle 13 is then opened, and the static cutter head 12 flips downward around the hinge 22 under the action of gravity. At this time, the soil stored in the hollow drill bit 10 is no longer blocked and can be tilted out, thereby achieving rapid soil discharge operations.

[0052] After the soil removal operation is completed, the static cutterhead 12 is flipped upward to a horizontal position and locked with the buckle 13. Then, the pile driver is adjusted again to rotate the hollow drill bit 10 to the top of the pile hole. The hollow drill bit 10 is then inserted into the bottom of the pile hole again to continue the drilling operation. This process is repeated until the square pile hole of the set depth is prepared.

[0053] When different requirements are placed on the hole size of the square pile hole, it is only necessary to replace the hollow drill bit 10 of the corresponding size, and the other components of the present invention are all universal parts.

[0054] The solutions in the embodiments are not intended to limit the patent protection scope of the present invention. Any equivalent implementation or modification that does not deviate from the present invention is included in the patent scope of this case.

Claims

1. A square pile hole rotary drilling device, characterized by: The jackup mechanism is connected with the hydraulic lifting mechanism on the pile driver column of the pile driver, the hydraulic lifting mechanism being connected with the hydraulic lifting mechanism on the pile driver column of the pile driver, the hydraulic lifting mechanism being connected with the hydraulic lifting mechanism on the pile driver column of the pile driver, the hydraulic lifting mechanism being connected with the hydraulic lifting mechanism on the pile driver column of the pile driver, the hydraulic lifting mechanism being connected with the hydraulic lifting mechanism on the pile driver column of the pile driver, the hydraulic lifting mechanism being connected with the hydraulic lifting mechanism on the pile driver column of the pile driver, the hydraulic lifting mechanism being connected with the hydraulic lifting mechanism on the pile driver column of the pile driver, the hydraulic lifting mechanism being connected with the hydraulic lifting mechanism on the pile driver column of the pile driver, the hydraulic lifting mechanism being connected with the hydraulic lifting mechanism on the pile driver column The power mechanism is meshed with the gear and the gear ring through the gear set at its power output end; a static cutter disc is provided at the bottom of the hollow drill bit, and the static cutter disc is in the shape of a Reuleaux triangle. One of the single sides of the static cutter disc is hinged to the hollow drill bit through a hinge, and the hinge position of the hinge is located in the middle of the single side of the Reuleaux triangle; a buckle is provided between the other two single sides of the static cutter disc and the hollow drill bit, and the installation position of the buckle is located in the middle of the single side of the Reuleaux triangle; There are three fan-shaped hollow holes distributed along the circumference of the stationary cutter disc, and a static tooth is fixed at the vertex of the Lelo triangle of the stationary cutter disc; a movable cutter disc is axially hinged at the bottom center of the stationary cutter disc, and the movable cutter disc adopts a fan-shaped three-blade structure, and movable teeth are fixed on the blades of the movable cutter disc; the size of the fan-shaped blades of the movable cutter disc is equal to the size of the fan-shaped hollow hole on the stationary cutter disc; a docking stop positioning block structure is provided between the static teeth and the movable teeth, and the rotation angle range of the movable cutter disc is limited by the docking stop positioning block structure.

2. The square pile hole rotary drilling equipment according to claim 1, characterized in that: The power mechanism adopts an electric drive gear transmission structure, and the power output end of the power mechanism is a gear set.

3. The square pile hole rotary drilling equipment according to claim 2, characterized in that: The gear and the ring gear rotate in opposite directions, and the speed ratio between the gear and the ring gear is 1:

3.

4. The square pile hole rotary drilling equipment according to claim 3, characterized in that: The excavation mechanism includes a transmission shaft, a hollow drill bit and an adapter sleeve; the cross-sectional shape of the hollow drill bit is a Lerow triangle; the transmission shaft is vertically fixed at the centroid of the top plate of the hollow drill bit, and a reinforcing rib is fixed between the transmission shaft and the top plate of the hollow drill bit. A second adapter flange is fixed at the top of the transmission shaft, and the second adapter flange at the top of the transmission shaft is transmission-connected to the first adapter flange at the bottom end of the solid drill rod through a universal joint; the transmission shaft and the solid drill rod are eccentrically distributed; the adapter sleeve is eccentrically sleeved on the outside of the transmission shaft, and the adapter sleeve and the transmission shaft are rotationally connected through a third bearing; an external thread is provided on the outer surface of the adapter sleeve, and the hollow drill rod and the adapter sleeve are coaxially screwed and fixed together.

5. The square pile hole rotary drilling equipment according to claim 4, characterized in that: The eccentricity between the adapter sleeve and the transmission shaft is the distance between any two vertices of the Reloj triangle of the hollow drill bit cross section. times.

6. The method for using the square pile hole rotary drilling equipment according to claim 5, characterized in that Specifically: When a square pile hole needs to be prepared, the pile driver is first moved to the drilling position so that the square pile hole rotary drilling equipment is located directly above the square pile hole calibration point. Then the power mechanism is started, and the gear set at its power output end transmits power to the gear and ring gear of the transmission mechanism respectively. At this time, the gear and ring gear rotate in opposite directions, and the speed ratio of the gear and ring gear is 1:3; When the gear rotates at a set speed, it drives the hollow drill bit to rotate in sequence through the solid drill rod, universal joint, and drive shaft. At the same time, when the ring gear rotates at a specific speed, it drives the adapter sleeve to rotate synchronously through the hollow drill rod, and then drives the drive shaft and hollow drill bit to revolve around the center of the adapter sleeve through the adapter sleeve. At this time, the speed ratio of the hollow drill bit's rotation and revolution is 1:3, and the directions are opposite. The motion trajectory of the vertices of the Reuleaux triangle in the cross section of the hollow drill bit forms a square. When the hollow drill bit rotates according to the set speed and motion trajectory, the adapter bracket is controlled to slide downward at a uniform speed along the pile driver column until the movable cutter disc at the bottom of the hollow drill bit first touches the ground. When the movable cutter disc touches the ground, the movement of the movable cutter disc is blocked by the resistance, and the static cutter disc continues to rotate with the hollow drill bit until the movable teeth on the movable cutter disc and the static teeth on the static cutter disc are completely stuck at the docking stop positioning block structure. At this time, the movable cutter disc and the static cutter disc remain relatively stationary, and the fan-shaped hollow holes on the static cutter disc are completely exposed; As the hollow drill bit rotates and the adapter bracket slides down at a constant speed along the pile driver column, the hollow drill bit gradually screws into the ground. At the same time, as the hollow drill bit continues to screw in, the soil in the ground enters the hollow drill bit through the fan-shaped hollow holes for temporary storage. When the soil inside the hollow drill bit is full, the rotation of the hollow drill bit is first paused, and then the power mechanism is started in the reverse direction to make the hollow drill bit rotate in the reverse direction. Under the action of resistance, the movement of the movable cutter disc is blocked again, and the stationary cutter disc continues to rotate with the hollow drill bit until the static teeth on the movable cutter disc and the stationary cutter disc are completely stuck at the docking stop and positioning block structure. At this time, the movable cutter disc and the stationary cutter disc remain relatively stationary, and the movable cutter disc completely blocks the fan-shaped hollow hole. When the fan-shaped hollow hole is completely blocked and closed by the moving cutterhead, the rotation of the hollow drill bit is stopped. Then the adapter bracket is controlled to slide upward at a constant speed along the pile driver column until the hollow drill bit is completely removed from the pile hole. Then the pile driver is adjusted to rotate the hollow drill bit to the ground above the pile hole. Then the buckle is opened, and the static cutterhead flips downward around the hinge under the action of gravity, causing the soil stored in the hollow drill bit to tilt out, thus completing the soil discharge operation. When the soil discharge operation is completed, the static cutterhead is flipped upward to a horizontal state and locked with a buckle. Then the pile driver is adjusted to turn the hollow drill bit to the top of the pile hole again, and then the hollow drill bit is sent back to the bottom of the pile hole to continue the drilling operation; and so on, until the preparation of the square pile hole of the set depth is completed.

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