Bidirectional stirring pile construction drilling tool capable of vibrating up and down

Abstract

The invention relates to a bidirectional stirring pile construction drilling tool capable of vibrating up and down, which comprises an outer drilling rod, an inner drilling rod, an outer stirring mechanism, an inner stirring mechanism and a drill bit, the outer drilling rod and the inner drilling rod are coaxially and rotatably mounted and rotate reversely, and the inner stirring mechanism comprises an inner rod arranged at the lower end of the inner drilling rod and inner stirring blades mounted on the inner rod; the outer stirring mechanism comprises outer frame plates fixed to the upper portion and the lower portion of the outer drill rod, an upper connecting shaft and a lower connecting shaft, the upper connecting shaft and the lower connecting shaft are rotationally installed on the upper outer frame plate and the lower outer frame plate respectively and sleeved with an outer sleeve, and outer stirring blades are arranged on the outer sleeve. The outer sleeve can move up and down in the axial direction to form an up-and-down vibration stirring state; radial migration of the whole section is achieved, during rapid rotation, the outer sleeve pipe vibrates up and down, the revolution of the outer frame and the rotation of the outer rod are combined, the effect of multi-dimensional rotation and up-down vibration is formed, and stirring is more uniform; and a structural foundation is laid for subsequent radial soil turning and uniform mixing.

Description

Technical Field

[0001] This invention relates to a bidirectional mixing pile construction drilling tool that can vibrate up and down, belonging to the technical field of pile foundation construction equipment. Background Technology

[0002] Cement mixing pile technology is one of the core technologies for soft soil foundation reinforcement. It uses mixing machinery to forcibly mix cement and other solidifying agents with the foundation soil, utilizing physicochemical reactions to harden the soft soil, thereby improving the foundation strength and stability. Due to the shearing effect brought about by the counter-rotation of the inner and outer drill rods, bidirectional mixing piles are superior to traditional single-axis mixing piles in terms of mixing uniformity, and have become one of the mainstream construction methods.

[0003] Currently, most mainstream bidirectional mixing pile drilling tools adopt a cage structure that combines an outer frame drill bit and an inner drill bit. This structure has significant defects in actual construction: when the stratum has high viscosity, the fixed outer frame is easily adhered to by the cohesive soil and gradually forms a soil ball, which prevents the mixing blades from contacting the fresh soil and causes the mixing effect to drop sharply; the mixing trajectory of the cage structure is fixed, and the mixing paddle cannot vibrate up and down, resulting in uneven distribution of slurry and affecting the bearing capacity of the composite foundation. Summary of the Invention

[0004] This invention provides a bidirectional mixing pile construction drilling tool that can vibrate up and down, solving the problems existing in the background art.

[0005] This invention provides a bidirectional mixing pile construction drilling tool capable of vertical vibration, comprising an outer drill rod and an inner drill rod coaxially rotatably mounted and rotating in opposite directions, an outer mixing mechanism, an inner mixing mechanism, and a drill bit. The inner mixing mechanism includes an inner rod disposed at the lower end of the inner drill rod and inner mixing blades mounted on the inner rod. The outer mixing mechanism includes an outer frame plate fixed above and below the outer drill rod, and an upper connecting shaft and a lower connecting shaft rotatably mounted on the upper and lower outer frame plates, respectively. A gap is provided between the upper connecting shaft and the lower connecting shaft. An outer sleeve is fitted onto the upper connecting shaft and the lower connecting shaft, and an outer mixing blade is disposed on the outer sleeve. The outer sleeve can move vertically along the axial direction to form a vertical vibration mixing state. A transmission mechanism is connected between the upper connecting shaft and the inner rod.

[0006] As a preferred embodiment, the transmission mechanism includes a driving gear mounted on the inner rod and a driven gear mounted on the upper connecting shaft, with the driving gear meshing with the driven gear for transmission. This allows for convenient transmission without affecting stirring.

[0007] As a preferred option, one end of the outer sleeve is connected by a key, and the other end is connected by a protrusion and a threaded groove. This dual connection method balances transmission stability and axial freedom of movement, ensuring that the outer sleeve rotates synchronously with the connecting shaft while providing a structural basis for vertical vibration, thus achieving an organic combination of rotation and vibration functions.

[0008] As a preferred embodiment, the upper inner hole of the outer sleeve is provided with a spline, the upper connecting shaft is provided with a spline groove that mates with the spline, the lower inner hole of the outer sleeve is provided with a protrusion, and the outer wall of the lower connecting shaft is provided with a threaded groove that mates with the protrusion. There are two threaded grooves, which are interconnected at the ends. The spline engagement provides high transmission accuracy and strong load-bearing capacity, while the threaded groove and protrusion structure is compact and reliable, ensuring that the outer sleeve can stably generate vertical vibrations.

[0009] As an alternative, multiple outer sleeves can be configured to vibrate asynchronously, i.e., with different thread groove shapes, to achieve different frequencies of vibration among the three outer sleeves. Different frequency vibrations can create complex mixing trajectories, break up soil agglomeration structures, further eliminate mixing dead zones, and are especially suitable for complex strata, improving mixing uniformity and soil breaking effect.

[0010] As a preferred embodiment, the lower end of the spline groove extends to the lower end of the upper connecting shaft, and the threaded groove extends to the upper end of the lower connecting shaft. This facilitates installation.

[0011] As a preferred embodiment, the number of outer sleeves is 2-4, arranged in a circular array along the axis of the inner rod. The upper and lower connecting shafts are connected to the outer frame plate via bearings. The inner end of the upper outer frame plate is fixed to the outer drill rod, while the inner end of the lower outer frame plate is rotatably mounted on the inner rod. The circular array arrangement ensures uniform mixing force, improving the quality of pile forming; the bearing connection reduces rotational friction, lowering energy consumption and wear; and the frame plate structural design ensures the overall stability of the external mixing mechanism, preventing displacement during operation.

[0012] As a preferred embodiment, both the inner and outer stirring blades are arranged radially, and both are layered, with 1-5 layers and 2-4 blades evenly distributed in each layer. The inner and outer stirring blades are spaced axially, and this spacing is greater than the maximum vertical movement height of the outer stirring blade. The layered radial blades expand the stirring coverage area and improve stirring efficiency; the axial safety spacing effectively prevents interference between the outer and inner stirring blades during vibration, ensuring safe and stable operation of the mechanism.

[0013] As a preferred embodiment, the system also includes a grout channel and a nozzle. The grout channel is a pipe. The nozzle is extended along the back of the inner mixing blades to the middle of the inner mixing blades or between the middle and the end of the blades. The nozzle is close to the mixing area, allowing the grout to be directly injected into the soil to be mixed. Combined with the vibration and mixing action, this promotes rapid diffusion and uniform mixing of the grout, improving the solidification effect of the pile.

[0014] As a preferred embodiment, both the inner and outer mixing blades are arranged radially, and both are layered, with 1-5 layers and 2-4 blades evenly distributed in each layer. A radial gap is provided between the outer end of the inner mixing blade and the inner end of the outer mixing blade. This radial gap prevents interference between the inner and outer blade movements, while simultaneously creating multiple shear surfaces to enhance the soil breaking effect, further improve mixing uniformity, and ensure consistent strength across all parts of the pile.

[0015] The present invention has the following beneficial effects: By replacing the fixed structure of the outer mixing mechanism with a rotatable outer sleeve, and using a transmission mechanism to drive the outer sleeve to rotate, cohesive soil cannot stably adhere to the outer frame and the outer sleeve, fundamentally preventing soil ball formation. Simultaneously, the inner and outer mixing blades rotate with the inner rod and outer sleeve respectively, forming a bidirectional composite mixing action. The outer sleeve drives the outer mixing blades to rotate, turning the slurry near the inner rod to the outside and turning the outer soil to the vicinity of the inner rod, thus achieving radial migration of the entire cross-section. Furthermore, by setting upper and lower connecting shafts to connect the outer sleeve, the outer sleeve can move up and down axially, creating a vertical vibration mixing state. When rotating rapidly, the outer sleeve exhibits vertical vibration, which, combined with the revolution of the outer frame and the rotation of the outer rod, forms a multi-dimensional rotation + vertical vibration effect, resulting in more uniform mixing. This lays the structural foundation for subsequent radial soil turning and uniform mixing. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 2 ; Figure 3 This is a schematic diagram of the main structure of the present invention; Figure 4 A top view schematic diagram of the present invention; Figure 5 This is a partial three-dimensional structural schematic diagram of the present invention; Figure 6 This is a partial front view structural diagram of the present invention; In the diagram: 1. Driven gear; 2. Outer stirring blade; 3. Outer sleeve; 4. Lower connecting shaft; 5. Upper connecting shaft; 6. Inner rod; 7. Drive gear; 8. Spline groove; 9. Threaded groove; 10. Outer frame plate; 11. Drill bit; 12. Outer drill rod; 13. Inner stirring blade; 14. Inner drill rod. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments. 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.

[0018] Example 1, as Figures 1 to 6 As shown, the present invention provides a bidirectional mixing pile construction drilling tool capable of vertical vibration, including an outer drill rod 12 and an inner drill rod 14 coaxially rotatably mounted and rotating in opposite directions, an outer mixing mechanism, an inner mixing mechanism, and a drill bit 11. The inner mixing mechanism includes an inner rod 6 disposed at the lower end of the inner drill rod 14 and inner mixing blades 13 mounted on the inner rod 6. The outer mixing mechanism includes an outer frame plate 10 fixed above and below the outer drill rod 12, an upper connecting shaft 5 and a lower connecting shaft 4 rotatably mounted on the upper and lower outer frame plates 10 respectively, with a gap between the upper connecting shaft 5 and the lower connecting shaft 4, and an outer sleeve 3 sleeved on the upper connecting shaft 5 and the lower connecting shaft 4, with outer mixing blades 2 disposed on the outer sleeve 3; the outer sleeve 3 can move vertically along the axial direction to form a vertical vibration mixing state; a transmission mechanism is connected to the upper connecting shaft 5 and the inner rod 6.

[0019] During construction, after the drilling rig is in place, the inner and outer drill rods rotate in opposite directions, the drill bit breaks through the soil and drills down, and the inner and outer mixing blades rotate in opposite directions to forcibly mix the slurry with the soil. Radial turning achieves uniform mixing across the entire cross-section. While the outer mixing blades rotate rapidly, they also vibrate up and down. Combined with the revolution of the outer frame and the rotation of the outer mixing blades, this creates a multi-dimensional rotation + up-and-down vibration effect, resulting in more uniform mixing. This lays the structural foundation for subsequent radial turning of the soil and achieving uniform mixing. After drilling to the designed depth, slurry is continuously sprayed and mixed for more than 10 seconds, then the drill string is raised in the opposite direction to the surface, completing the single pile construction. For multi-pile interlocking construction, the center distance between adjacent piles is adjusted, and the rotation trajectory of the outer mixing blades achieves staggered interlocking at the edges.

[0020] In Example 2, based on Example 1, the transmission mechanism includes a driving gear 7 mounted on the inner rod 6 and a driven gear 1 mounted on the upper connecting shaft 5. The driving gear 7 and the driven gear 1 mesh and transmit power. When the driving gear 7 and the driven gear 1 mesh, a gap is left between the root of the gear and the tip of the tooth to prevent particles from getting stuck.

[0021] One end of the outer tube 3 is connected by a key, and the other end is connected by a protrusion and a threaded groove 9. Both the outer drill rod 12 and the inner drill rod 14 are machined from 45# seamless steel pipe. The upper inner hole of the outer sleeve 3 is provided with a spline, and the upper connecting shaft 5 is provided with a spline groove 8 that mates with the spline. The lower inner hole of the outer sleeve 3 is provided with a protrusion, and the outer wall of the lower connecting shaft 4 is provided with a threaded groove 9 that mates with the protrusion. When connecting the outer sleeve 3, first put the outer sleeve 3 on the upper connecting shaft 5, and then move it downward so that the lower protrusion engages with the threaded groove 9. There are two threaded grooves 9, and the two threaded grooves 9 are connected to each other at the ends. When the protrusion rises to the top along one threaded groove 9, it will enter the other threaded groove 9, and then descend along the other threaded groove 9. When it descends to the bottom, it will enter the original threaded groove 9 and rise again.

[0022] Multiple outer tubes 3 can be set to vibrate asynchronously, that is, the threaded grooves 9 have different shapes, so that the three outer tubes 3 vibrate at different frequencies.

[0023] The lower end of the spline groove 8 extends to the lower end of the upper connecting shaft 5, and the threaded groove 9 extends to the upper end of the lower connecting shaft 4. Connect the drill bit to the power output end of the construction machinery, start the power system, adjust the rotation speed of the outer drill rod 12 and the inner drill rod 14, observe the vibration of the outer sleeve 3, and ensure that the three outer sleeves 3 vibrate up and down at different frequencies, and the vibration amplitude meets the design requirements; check whether the blade rotation is smooth, without jamming or abnormal noise.

[0024] The number of outer sleeves 3 is 2-4, preferably 3, and the outer sleeves 3 are arranged in a circular array along the axis of the inner rod 6; the upper connecting shaft 5 and the lower connecting shaft 4 are connected to the outer frame plate 10 by bearings, the inner end of the upper outer frame plate 10 is fixed to the outer drill rod 12, and the inner end of the lower outer frame plate 10 is rotatably mounted on the inner rod 6.

[0025] Both the inner stirring blade 13 and the outer stirring blade 2 are arranged radially. Both are layered, with 1-5 layers and 2-4 blades evenly distributed in each layer. The inner stirring blade 13 and the outer stirring blade 2 are spaced axially, and this distance is greater than the maximum vertical movement height of the outer stirring blade 2. When the inner stirring blade 13 and the outer stirring blade 2 rotate, the outer stirring blade 2 will slide axially up and down, but this sliding distance is limited and will not cause contact or collision between the inner stirring blade 13 and the outer stirring blade 2.

[0026] It also includes a slurry channel and a nozzle, wherein the slurry channel is a pipe; the nozzle is extended along the back of the inner stirring blade 13 to the middle of the inner stirring blade 13 or between the middle and the end.

[0027] In Example 3, unlike Example 2, both the inner stirring blade 13 and the outer stirring blade 2 are arranged radially. Both blades are layered, with 1-5 layers, and each layer has 2-4 blades evenly distributed, preferably 3 blades. A radial gap is provided between the outer end of the inner stirring blade 13 and the inner end of the outer stirring blade 2. With this structure, the lifting height of the outer stirring blade 2 does not need to be considered, and neither the inner stirring blade 13 nor the outer stirring blade 2 will cause collision interference.

[0028] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0029] In the description of this invention, the terms "inner", "outer", "longitudinal", "lateral", "upper", "lower", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and do not require that this invention must be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

Claims

1. A bidirectional mixing pile construction drilling tool capable of vertical vibration, comprising an outer drill rod (12) and an inner drill rod (14) coaxially mounted and rotating in opposite directions, an outer mixing mechanism, an inner mixing mechanism, and a drill bit (11), characterized in that: The internal stirring mechanism includes an inner rod (6) located at the lower end of the inner drill rod (14) and an inner stirring blade (13) mounted on the inner rod (6). The external stirring mechanism includes an outer frame plate (10) fixed above and below the outer drill rod (12), an upper connecting shaft (5) and a lower connecting shaft (4) rotatably mounted on the upper and lower outer frame plates (10) respectively. There is a gap between the upper connecting shaft (5) and the lower connecting shaft (4). An outer sleeve (3) is sleeved on the upper connecting shaft (5) and the lower connecting shaft (4). An outer stirring blade (2) is provided on the outer sleeve (3). The outer sleeve (3) can move up and down along the axial direction to form a stirring state of up and down vibration. A transmission mechanism is connected between the upper connecting shaft (5) and the inner rod (6).

2. The bidirectional mixing pile construction drilling tool capable of vertical vibration according to claim 1, characterized in that: The transmission mechanism includes a drive gear (7) mounted on the inner rod (6) and a driven gear (1) mounted on the upper connecting shaft (5), and the drive gear (7) meshes with the driven gear (1) for transmission.

3. The bidirectional mixing pile construction drilling tool capable of vertical vibration according to claim 1, characterized in that: One end of the outer tube (3) is connected by a key, and the other end is connected by a protrusion and a threaded groove (9).

4. The bidirectional mixing pile construction drilling tool capable of vertical vibration according to claim 3, characterized in that: The upper end of the outer tube (3) is provided with a spline in the inner hole, the upper connecting shaft (5) is provided with a spline groove (8) that mates with the spline, the lower end of the outer tube (3) is provided with a protrusion in the inner hole, the lower connecting shaft (4) is provided with a threaded groove (9) that mates with the protrusion on the outer wall, there are two threaded grooves (9), and the two threaded grooves (9) are connected to each other at the ends.

5. The bidirectional mixing pile construction drilling tool capable of vertical vibration according to claim 4, characterized in that: Multiple outer tubes (3) are set to vibrate asynchronously, that is, the thread grooves (9) have different shapes, so that the three outer tubes (3) vibrate at different frequencies.

6. The bidirectional mixing pile construction drilling tool capable of vertical vibration according to claim 4, characterized in that: The lower end of the spline groove (8) extends to the lower end of the upper connecting shaft (5), and the threaded groove (9) extends to the upper end of the lower connecting shaft (4).

7. A bidirectional mixing pile construction drilling tool capable of vertical vibration according to any one of claims 1-6, characterized in that: There are 2-4 outer tubes (3), which are arranged in a circular array along the axis of the inner rod (6); the upper connecting shaft (5) and the lower connecting shaft (4) are connected to the outer frame plate (10) by bearings. The inner end of the upper outer frame plate (10) is fixed to the outer drill rod (12), and the inner end of the lower outer frame plate (10) is rotatably mounted on the inner rod (6).

8. The bidirectional mixing pile construction drilling tool capable of vertical vibration according to claim 1, characterized in that: The inner stirring blade (13) and the outer stirring blade (2) are arranged radially. The inner stirring blade (13) and the outer stirring blade (2) are arranged in layers, with 1-5 layers and 2-4 blades evenly arranged in each layer. The inner stirring blade (13) and the outer stirring blade (2) are spaced along the axial direction, and this space is greater than the maximum height of the outer stirring blade (2) moving up and down.

9. A bidirectional mixing pile construction drilling tool capable of vertical vibration according to claim 1, characterized in that: It also includes a slurry channel and a nozzle, the slurry channel being a pipe; the nozzle is extended along the back of the inner stirring blade (13) to the middle of the inner stirring blade (13) or between the middle and the end.

10. A bidirectional mixing pile construction drilling tool capable of vertical vibration according to claim 1, characterized in that: The inner stirring blade (13) and the outer stirring blade (2) are arranged radially. The inner stirring blade (13) and the outer stirring blade (2) are arranged in layers, with 1-5 layers and 2-4 blades evenly arranged in each layer. There is a radial gap between the outer end of the inner stirring blade (13) and the inner end of the outer stirring blade (2).

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