WO2020042846A1

WO2020042846A1 - Drill body

Info

Publication number: WO2020042846A1
Application number: PCT/CN2019/098082
Authority: WO
Inventors: 周兆弟
Original assignee: 周兆弟
Priority date: 2018-08-31
Filing date: 2019-07-29
Publication date: 2020-03-05
Also published as: AU2019330308A1; CN110872838A; ZA202102137B; AU2019330308B2

Abstract

A drill body, which comprises: a hollow transmission shaft (1); and a hollow drill rod (3) being axially sheathed on the hollow transmission shaft (1) and integrally rotating along with the hollow transmission shaft (1), wherein an upper discharge port (121) and a lower discharge port (122) are formed in the hollow transmission shaft (1) at intervals in an axial direction; the hollow drill rod (3) is provided with an upper nozzle (31) and a lower nozzle (32) at intervals in the axial direction; the hollow drill rod (3) can axially reciprocate relative to the hollow transmission shaft (1), and the lower discharge port (122) is in communication with the lower nozzle (32) when drilling in; and when drilling out, the upper discharge port (121) is in communication with the upper nozzle (31).

Description

Drill body

This application claims priority from a Chinese patent application filed with the Chinese Patent Office on August 31, 2018, with an application number of 201811010914.0, and the invention name is "a drill body." The entire contents of this patent are incorporated herein by reference. Applying.

Technical field

The invention relates to the field of pile foundation construction, in particular to a drill body for pile foundation construction.

Background technique

Cement soil mixing pile is a method for strengthening saturated and soft clay ground. It uses cement as a curing agent, through special mixing machinery, forcibly stirs the soft soil and curing agent in the depth of the foundation, and uses the curing agent and soft soil. A series of physical and chemical reactions between them make the soft soil hard to form a high-quality foundation with integrity, water stability and certain strength.

When the existing pile driver performs the cement soil mixing pile construction operation, a spraying port is provided at the lower end of the drill pipe to perform bottom spraying during drilling, and the cement slurry cannot be stirred when the drill pipe is reversed and withdrawn. Uneven mixing will affect the overall structural strength of the cement-soil mixing pile.

In view of the above problems, the prior art provides a cement-soil mixing pile device capable of up and down spraying. The cement-soil mixing pile device includes a drill pipe, a combined slurry inlet pipe built in the drill pipe, and sequentially axially communicating with each other. The control valve, the side wall of the drill pipe is provided with an upper spraying port and a lower spraying port respectively communicating with the slurry inlet pipe; the gas control valve controls the upper spraying port, the lower spraying port and the combination through inflation and exhaust. The switching of the slurry inlet pipe is conducted.

Although the above-mentioned cement-soil mixing pile device can achieve shotcrete at the bottom of the drill pipe when drilling down and shotcrete at the upper part of the drill pipe when lifting, the upper and lower shotcrete ports, the lower shotcrete port and the combined grout pipe need to be switched on The way of turning the air control valve control switch to realize the operation control, therefore, the degree of automation is not good.

Summary of the Invention

The purpose of the present invention is to solve the problem that the existing drill pipe lacks the automatic control of the upper and lower nozzle switching operations.

In order to achieve the object of the present invention, the present invention adopts the following technical solutions:

A drill body has the following features, including:

Hollow drive shaft; and

A hollow drill pipe, which is axially sheathed on the hollow drive shaft and rotates integrally with the hollow drive shaft;

Wherein, the axial length of the hollow transmission shaft is greater than the axial length of the hollow drill rod, and the hollow transmission shaft is axially spaced with an upper discharge opening and a lower discharge opening; and the hollow drill shaft is axially spaced Set the upper and lower nozzles;

The hollow drill rod can reciprocate axially relative to the hollow drive shaft. When drilling, the lower discharge port and the lower nozzle are in communication with each other; when the drill is withdrawn, the upper discharge port and The upper nozzles are electrically connected.

Further, the above drill body further has the following characteristics: the distance between the upper nozzle and the lower nozzle is a distance L1, and the distance between the upper discharge port and the lower discharge port is a distance L2, the diameter of the upper discharge opening is a diameter D, and the sum of the distance L2 and the diameter D is equal to the distance L1;

The hollow drill rod is provided with a waist-shaped hole in the axial direction, and the hollow transmission shaft is radially installed with a stopper rod penetrating the waist-shaped hole, and the reciprocating distance of the stopper rod in the waist-shaped hole is equal to The diameter D.

Further, the above drill body further has the following characteristics: the hollow transmission shaft includes an upper shaft section and a lower shaft section which are axially connected, and an output shaft of the power device is axially connected with the upper shaft section;

The hollow drill pipe is sheathed axially on the lower shaft section of the hollow transmission shaft, and the upper discharge opening and the lower discharge opening are spaced from the lower shaft section of the hollow transmission shaft;

An outer peripheral wall of the lower shaft segment has at least one flat surface, and a contoured hole matching the lower shaft segment is axially opened on the top end surface of the hollow drill rod.

Further, the above drill body also has the following features: it further includes: an elastic element built in the contoured hole, and two ends of the elastic element respectively abut the bottom of the contoured hole and the lower shaft. The lower end of the segment.

Further, the above drill body further has the following features: a lower end of the hollow drill rod is provided with a cutting portion, and the cutting portion includes:

A drill tip formed with a cutting edge; and

At least one turn of a spiral wing disposed on the outer peripheral surface of the hollow drill rod and close to the drill tip;

Wherein, the spiral wing forms a continuous cutting edge on a radial end face near the drill tip;

Alternatively, the spiral wing is provided with a plurality of detachable shovel teeth on a radial end surface near the drill point.

Further, the above drill body also has the following features: the drill point is provided with at least two spiral cutting edges around the central axis, and each of the spiral cutting edges is spaced around the central axis of the central drill rod. .

Further, the above drill body further has the following characteristics: a plurality of stirring blades are arranged on the outer peripheral wall of the hollow drill pipe at intervals, and the maximum rotation diameter of the stirring blade around the center axis of the hollow drill pipe is less than or equal to the hollow drill pipe Maximum drilling diameter of the rod.

Further, the above drill body also has the following features: every two to five stirring blades are arranged around the central axis of the hollow drill rod to form a radial stirring blade group, and each radial stirring blade group is along the hollow drill rod. The central axis is arranged at intervals;

Alternatively, each of the stirring blades is spirally arranged around an outer peripheral wall of the drill pipe.

Further, the above drill body also has the following feature: the stirring blade is arranged obliquely with respect to the cross section of the hollow drill rod.

Further, the above drill body further has the following features, further comprising: a power device for driving the hollow transmission shaft to rotate; and

A rigid outer tube axially sleeved on the upper shaft section of the hollow transmission shaft and supporting the power unit on the top;

The output shaft of the power unit is axially connected to the upper shaft segment, and the bottom of the rigid outer tube and the upper shaft segment are movably connected by a sliding sleeve or a bearing;

At least one radial channel is provided on the upper peripheral surface of the rigid outer tube, and an annular groove is formed on the inner peripheral wall of the rigid outer tube to communicate with the radial channel.

Further, the above drill body also has the following features: the hollow transmission shaft is provided with a radial hole communicating with its own axial center hole and the annular groove;

Alternatively, the output shaft has an axial hole communicating with a shaft center hole in the hollow transmission shaft, and the output shaft is provided with a radial hole communicating with the annular groove and the axial hole;

Alternatively, the rigid outer tube and the power unit are connected by a cylindrical object. An inner circumferential wall of the cylindrical object is provided with an annular groove, and the diameter of the cylindrical object is radially connected to the outer peripheral wall and the annular groove. Directional hole, the output shaft penetrating the cylindrical object has an axial hole communicating with the central hole of the hollow transmission shaft, and the output shaft is provided with a radial hole communicating with the annular groove and the axial hole .

The drill body structure provided by the present invention allows the hollow drill rod to move axially back and forth relative to the hollow drive shaft. When drilling, under the action of the resistance of the cutting body, the hollow drill rod moves axially upward relative to the hollow drive shaft so that The upper discharge port and the upper nozzle are isolated, and the lower discharge port is in communication with the lower nozzle. At this time, the lower nozzle can spray fluid to the drilling area; when the drill is withdrawn, the dead weight of the hollow drill pipe Under the action, the axial movement of the hollow drill rod relative to the hollow drive shaft causes the lower discharge port and the lower nozzle to be isolated, and the upper discharge port and the upper nozzle communicate with each other. At this time, the lower nozzle can spray fluid to the stirring area. With such a structural design, when the drill body enters or withdraws, the corresponding lower nozzle spray or upper nozzle spray can be achieved without artificially switching the conduction mode, and the drill body can be evenly stirred to ensure the cement soil mixing. The overall structural strength of the pile.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a drill body in the first embodiment.

Fig. 2 is a front view of a drill body in the first embodiment.

FIG. 3 is a schematic structural diagram of a lower shaft segment in Embodiment 1. FIG.

FIG. 4 is an axial sectional view of a hollow drill pipe in Embodiment 1. FIG.

5 is an axial sectional view of a drill body in the first embodiment.

FIG. 6 is an enlarged view of a portion corresponding to the letter A in FIG. 5.

FIG. 7 is an enlarged view of a portion corresponding to the letter B in FIG. 5.

FIG. 8 is a schematic assembly diagram of a hollow drill pipe and a lower shaft section in Embodiment 2. FIG.

FIG. 9 is a schematic diagram of the internal structure of the drill body at the top of the rigid outer tube in the third embodiment.

10 is a schematic diagram of the internal structure of the drill body at the top of the rigid outer tube in the fourth embodiment.

In the drawings:

100. Drill body;

1. Hollow transmission shaft; 11, upper shaft section; 12, lower shaft section; 121, upper discharge port; 122, lower discharge port; 123, flat surface; 124, blocking rod; 13, shaft hole; 14, Radial hole; 15, shaft hub;

2, power unit; 21, output shaft; 211, axial hole; 212, radial hole;

3. Hollow drill pipe; 31, upper nozzle; 32, lower nozzle; 33, contoured hole; 34, cutting part; 341, drill tip; 342, spiral wing; 343, cutting edge; 344, shovel tooth; 35, stirring Blades; 36, waist-shaped holes;

4. Elastic components;

5. Rigid outer tube; 51, radial channel; 52, annular groove;

6, sealed body;

7, curved cover; 71, inclined wedge surface; 72, fasteners;

8, sliding sleeve;

9. Cylinder; 91. Annular groove; 92. Radial hole.

detailed description

In order to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are part of the present invention. Examples, not all examples.

As shown in FIGS. 1, 2 and 5, the drill body 100 provided in this embodiment is used for pile foundation construction in the case of a cement-soil mixing pile. The drill body 100 includes a hollow transmission shaft 1, a power device 2, and a hollow drill. Rod 3 and rigid outer tube 5.

As shown in FIG. 1 and FIG. 2, the lower end of the hollow drill rod 3 is provided with a cutting portion 34. The cutting portion 34 includes a drill tip 341 and at least one spiral wing 342. Specifically, the drill tip 341 is formed with a cutting edge 343 and a spiral wing. 342 is disposed on the outer peripheral surface of the hollow drill pipe 3 and is close to the drill tip 341; the spiral wing 342 and the hollow drill pipe 3 are welded and fixed. The spiral wing 342 has a plurality of detachable shovel teeth 344 arranged on a radial end surface near the drill point 341. Of course, in the drill body 100 provided by the present invention, the spiral wing 342 forms a continuous cutting edge on a radial end surface near the drill point 341.

As shown in FIG. 1 and FIG. 2, as a preferred technical solution, in this embodiment, at least two spiral cutting edges 343 having a spiral angle of 5 ° to 85 ° are arranged around the central axis of the drill point 341, and each spiral shape The cutting edges 343 are spaced around the central axis of the center drill rod. The rod body and the drill point 341 of the hollow drill rod 3 are welded and fixed, or the hollow drill rod 3 and the drill point 341 are screwed and fixed by a fastener not shown in the figure, or the hollow drill rod 3 and the drill point 341 are axially screwed. fixed.

As shown in FIGS. 1 and 2, a plurality of stirring blades 35 are arranged on the outer peripheral wall of the hollow drill rod 3 at intervals. The stirring blades 35 extend radially outward from the outer peripheral wall of the hollow drill rod 3. Of course, the rigid outer tube 5 may also be uniformly distributed with several stirring blades 35 not shown in the figure. In addition, the maximum turning diameter of the stirring blade 35 around the center axis of the hollow drill rod 3 is less than or equal to the maximum drilling diameter of the hollow drill rod 3, so that the stirring blade 35 can fully and uniformly stir the object or solid-liquid mixture that has been cut and broken.

As shown in FIG. 2, as a preferred technical solution, every two to five stirring blades 35 are arranged around the central axis of the hollow drill rod 3 to form a radial stirring blade group, and each radial stirring blade group is along the hollow drill rod 3. The central axes are spaced. When multiple drill bodies 100 with similar structures are combined to form a pile foundation for construction, such a structural design can prevent the drill bodies 100 from interfering with each other.

As shown in FIG. 1 and FIG. 2, in order to reduce the axial movement resistance of the drill body 100 during drilling or withdrawal, the cross section of the stirring blade 35 with respect to the hollow drill rod 3 is arranged obliquely. In detail, the length direction of the stirring blade 35 is perpendicular to the axial direction of the hollow drill rod 3, and the blade surface of the stirring blade 35 is inclined to the central axis of the hollow drill rod 3.

Of course, in the drill body 100 provided by the present invention, for a single-operating drill body 100, or a combination drill composed of a plurality of drill bodies 100 of similar structure to perform the pile foundation construction as a whole, the interval between the drill bodies 100 When the rotation speed is sufficient and / or the rotation speed is constant, the stirring blades 35 may be spirally arranged around the outer peripheral wall of the hollow drill rod 3.

As shown in FIGS. 3 to 5, the axial length of the hollow transmission shaft 1 is greater than the axial length of the hollow drill rod 3. The hollow transmission shaft 1 includes an upper shaft section 11 and a lower shaft section 12, and the hollow transmission shaft 1 is axially spaced apart. An upper discharge opening 121 and a lower discharge opening 122 are provided. Preferably, the discharge opening 121 and the lower discharge opening 122 are spaced from the lower shaft section 12 of the hollow transmission shaft 1; the hollow drill rod 3 is arranged along the axial interval. Nozzle 31 and lower nozzle 32. When drilling, the hollow transmission shaft 1 moves axially downward relative to the hollow drill rod 3 so that the lower discharge port 122 and the lower nozzle 32 are in communication with each other, and the upper discharge port 121 and the upper nozzle 31 are isolated; when the drill is withdrawn The hollow transmission shaft 1 moves axially upward relative to the hollow drill rod 3 so that the upper discharge port 121 and the upper nozzle 31 are in communication with each other, and the lower discharge port 122 and the lower nozzle 32 are isolated.

As shown in FIG. 3 to FIG. 5, specifically, the power device 2 is used to drive the hollow transmission shaft 1 to rotate, and the upper shaft section 11 and the lower shaft section 12 are axially docked by the shaft hub 15 and rotate integrally and synchronously. As shown in the figure, the output shaft 21 and the upper shaft section 11 of the power unit 2 are axially connected by a shaft hub. In addition, the hollow drill rod 3 can move back and forth axially relative to the hollow transmission shaft 1.

As shown in FIG. 3 to FIG. 5, the hollow drill rod 3 is sleeved on the hollow transmission shaft 1 axially and rotates integrally with the hollow transmission shaft 1. Specifically, the hollow drill rod 3 is axially sleeved on the lower shaft section 12 of the hollow transmission shaft 1. The outer peripheral wall of the lower shaft segment 12 has at least one flat surface 123, and the hollow drill rod 3 is provided with a contour hole 33 matching the lower shaft segment 12 in the axial direction at the top end surface. Such a structural design can prevent the hollow drill rod 3 from transmitting to the hollow The shaft 1 rotates in the circumferential direction.

As shown in FIG. 3 to FIG. 5, in this embodiment, the distance between the upper nozzle 31 and the lower nozzle 32 is a linear distance L1, and the distance between the upper discharge port 121 and the lower discharge port 122 is a linear distance L2. The diameter of the upper discharge port 121 is a diameter D. In order to ensure that the lower discharge port 122 and the lower nozzle 32 are completely communicated when the drill is fed, the upper discharge port 121 and the upper nozzle 31 are completely communicated when the drill is withdrawn, and the straight line distance L2 is equal to the diameter D. The sum is equal to the linear distance L1.

As shown in Figs. 5 and 6, in order to prevent the hollow drill rod 3 and the hollow transmission shaft 1 from being axially separated when the drill body 1 is withdrawn, the hollow drill rod 3 is provided with a waist-shaped hole 36 in the axial direction, and the lower shaft section 12 is along the diameter. A blocking rod 124 penetrating the waist-shaped hole 36 is installed, and the blocking rod 124 follows the hollow drill rod 3 to reciprocate axially with respect to the hollow transmission shaft 1. That is, the blocking rod 124 and the waist-shaped hole 36 are combined to form a detachment prevention device. However, it is necessary to ensure that the reciprocating distance of the blocking rod 124 in the waist hole 36 is equal to the diameter D of the upper discharge port 121. This size design can ensure that when the drill body enters the drill, the lower discharge port 122 and the lower nozzle 32 is completely conductive; when backing out, the upper discharge port 121 and the upper nozzle 31 are completely conductive.

As shown in Figs. 5 and 6, in order to prevent the broken body from entering the waist hole 36 during the construction of the pile foundation to affect the stroke of the retaining rod 124 to and fro, the retaining rod 124 can also be fitted with an arc cover 7 close to the outer peripheral wall of the hollow drill rod 3. The arc-shaped cover 7 moves synchronously with the blocking bar 124, and the arc-shaped cover 7 can effectively cover the waist-shaped hole 36 no matter which end of the blocking bar 124 is located at the waist-shaped hole 36. Of course, the arc cover 7 and the blocking rod 124 are preferably detachably connected by fasteners 72. With such a structural design, even if a part of the small broken body enters the waist-shaped hole 36, the arc cover 7 can be regularly removed for cleaning. maintain.

As shown in FIG. 5 and FIG. 6, it is more preferable that both ends of the arc-shaped cover 7 are designed as inclined wedge surfaces 71 in the axial direction of the drill body 100. The blade body formed by the wedge surface 71 has such a structural design that the broken body or the viscous solid-liquid mixture attached to the outer peripheral wall of the hollow drill pipe 3 can be eliminated while the arc cover 7 is reciprocating.

As shown in FIG. 2, FIG. 5 and FIG. 7, in this embodiment, the rigid outer tube 5 is axially sleeved on the upper shaft segment 11 of the hollow transmission shaft 1 and supports the power unit 2 on the top, and the bottom and the upper shaft of the rigid outer tube 5 The segments 11 are movably connected by a sliding sleeve 8 so that the upper shaft segment 11 can rotate freely with respect to the rigid outer tube 5. Specifically, the rigid outer tube 5 and the power device 2 are connected by a cylinder 9. An inner circumferential wall of the cylinder 9 is provided with an annular groove 91, and the diameter of the cylindrical 9 is connected to the outer peripheral wall and the annular groove 91 in a radial direction. The direction hole 92, the output shaft 21 penetrating the cylindrical member 9 has an axial hole 211 communicating with the shaft center hole 13 in the hollow transmission shaft 1, and the output shaft 21 is provided with a radial hole 212 communicating with the annular groove 91 and the axial hole 211. .

As shown in FIG. 2, FIG. 5, and FIG. 7, there is a slight radial clearance between the output shaft 21 of the power unit 2 and the barrel 9 to ensure that the output shaft 21 can rotate freely relative to the barrel 9. The entry of fluid (gas or cement slurry) leads to interference with the normal operation of the power unit 2 and the freedom of movement of the hollow transmission shaft 1 relative to the rigid outer tube 5. The cylinder 9 is embedded with seals on the axial sides of the annular groove 91 respectively. Body 6. The sealing body 6 may be single or plural, and the materials and structures of the sealing bodies 6 may be different.

As shown in FIG. 2, FIG. 5, and FIG. 7, in the above-mentioned structure, when the drill body 100 is drilled, the fluid (gas or cement slurry) sequentially passes through the radial hole 92, the annular groove 91, the radial hole 212, and the axial direction. The hole 211, the axial hole 13 and the lower discharge port 122 are transported to the lower nozzle 32 to discharge the drill body 100. When the drill body 100 is withdrawn, the fluid (gas or cement slurry) passes through the radial hole 92, the annular groove 91, The radial hole 212, the axial hole 211, the axial center hole 13 and the upper discharge port 121 are conveyed to the upper nozzle 31 and discharged from the drill body 100.

As shown in FIG. 2, in this embodiment, as a preferred fact solution, when the drill body 100 is drilled, the fluid discharged from the drill body 100 through the lower nozzle 32 is cement slurry; when the drill body 100 is withdrawn, the upper nozzle is used. 31 The fluid discharged from the drill body 100 is a gas (such as compressed air). Of course, when the drill body 100 provided by the present invention is used, the fluid discharged from the drill body 100 through the upper nozzle 31 or the lower nozzle 32 during the drilling or withdrawal of the drill body 100 is all cement slurry.

In this embodiment, the same parts as those in the first embodiment are given the same reference numerals, and the same text description is omitted.

As shown in FIG. 8, compared to the first embodiment, the drill body 100 provided in this embodiment also has such a different structural design. The drill body 100 provided in this embodiment further includes an elastic element 4. Specifically, the elastic element 4 is built in In the contoured hole 33, and the two ends of the elastic element 4 abut the bottom of the contoured hole 33 and the lower end of the lower shaft section 12, respectively, in order to ensure the effective operation of the elastic element 4, the elastic deformation amplitude of the elastic element 4 is equal to or greater than The diameter D of the upper discharge opening 121. When the drill body 100 is drilled, the hollow transmission shaft 1 presses down the elastic element 4 to shorten the axial direction. In this case, the lower discharge port 122 and the lower nozzle 32 communicate with each other.

Compared with the first embodiment, the role of the elastic element 4 is that when the drill body 100 is withdrawn, the axial compression force experienced by the elastic element 4 is eliminated and the axial length of the elastic element 4 is extended. The bottom of the profiled hole 33 and the lower end of the lower shaft section 12 help the hollow drill rod 3 to move axially downward with respect to the hollow rotating shaft, and meet the condition that the upper discharge port 121 and the upper nozzle 31 are in communication. In this embodiment, the elastic element 4 is preferably a compression spring. Of course, in the drill body 100 provided by the present invention, the elastic element 4 may also be a retractable elastic ring made of a material with elastic properties such as polyurethane.

As shown in FIG. 9, compared to the first embodiment, the drill body 100 provided in this embodiment also has such a different structural design: the upper end peripheral surface of the rigid outer tube 5 is provided with at least one radial channel 51, and the rigid outer tube 5 An annular groove 52 communicating with the radial channel 51 is provided on the inner peripheral wall, and the hollow transmission shaft 1 is provided with a radial hole 14 communicating with its own axial center hole 13 and the annular groove 52.

Under this structure design, when the drill body 100 is drilled, the fluid (gas or cement slurry) is conveyed through the radial channel 51, the annular groove 52, the radial hole 14, the shaft hole 13 and the lower discharge port 122 in order. To the lower nozzle 32, the drill body 100 is discharged; when the drill body 100 is withdrawn, the fluid (gas or cement slurry) sequentially passes through the radial channel 51, the annular groove 52, the radial hole 14, the shaft hole 13 and the upper discharge port. After 121, it is conveyed to the upper nozzle 31 to discharge the drill body 100.

Compared with the first embodiment, the drill body 100 provided in this embodiment omits the barrel 9, which can make the drill body 100 more compact in structure.

As shown in FIG. 10, compared to the first embodiment, the drill body 100 provided in this embodiment also has such a different structural design: the upper peripheral surface of the rigid outer tube 5 is provided with at least one radial channel 51, and the rigid outer tube 5 has An annular groove 52 communicating with the radial channel 51 is provided on the inner peripheral wall. The output shaft 21 has an axial hole 211 communicating with the shaft center hole 13 in the hollow transmission shaft 1. The output shaft 21 is provided with an annular groove 52 and an axial hole. 211 的平面孔 212。 Radial hole 212 of 211.

With this structural design, when the drill body 100 is drilled, the fluid (gas or cement slurry) passes through the radial channel 51, the annular groove 52, the radial hole 212, the axial hole 211, the shaft hole 13 and the lower hole in order. After the material port 122 is conveyed to the lower nozzle 32 to discharge the drill body 100; when the drill body 100 is withdrawn, the fluid (gas or cement slurry) sequentially passes through the radial channel 51, the annular groove 52, the radial hole 212, and the axial hole 211 , The shaft center hole 13 and the upper discharge port 121 are conveyed to the upper nozzle 31 to discharge the drill body 100.

The technical principles of the present invention have been described above in conjunction with specific embodiments, but it should be noted that the above descriptions are only for explaining the principles of the present invention, and cannot be construed in any way as specific limitations on the protection scope of the present invention. Based on the explanations herein, those skilled in the art can think of other specific embodiments or equivalent replacements of the present invention without paying any creative work, and all will fall into the protection scope of the present invention.

Claims

A drill body, comprising:

Hollow drive shaft; and

A hollow drill pipe, which is axially sheathed on the hollow drive shaft and rotates integrally with the hollow drive shaft;

Wherein, the axial length of the hollow transmission shaft is greater than the axial length of the hollow drill rod, and the hollow transmission shaft is axially spaced with an upper discharge opening and a lower discharge opening; and the hollow drill shaft is axially spaced Set the upper and lower nozzles;

The hollow drill rod can reciprocate axially relative to the hollow drive shaft. When drilling, the lower discharge port and the lower nozzle are in communication with each other; when the drill is withdrawn, the upper discharge port and The upper nozzles are electrically connected.
The drill body according to claim 1, wherein a distance between the upper nozzle and the lower nozzle is a distance L1, and a distance between the upper discharge port and the lower discharge port is a distance L2, the diameter of the upper discharge opening is a diameter D, and the sum of the distance L2 and the diameter D is equal to the distance L1;

The hollow drill rod is provided with a waist-shaped hole in the axial direction, and the hollow transmission shaft is radially installed with a stopper rod penetrating the waist-shaped hole, and the reciprocating distance of the stopper rod in the waist-shaped hole is equal to The diameter D.
The drill body according to claim 1, wherein the hollow transmission shaft comprises an upper shaft section and a lower shaft section which are axially butted;

The hollow drill pipe is sheathed axially on the lower shaft section of the hollow transmission shaft, and the upper discharge opening and the lower discharge opening are spaced from the lower shaft section of the hollow transmission shaft;

An outer peripheral wall of the lower shaft segment has at least one flat surface, and a contoured hole matching the lower shaft segment is axially opened on the top end surface of the hollow drill rod.
The drill body according to claim 3, further comprising: an elastic element built into the contoured hole, and two ends of the elastic element abut the bottom of the contoured hole and the lower shaft, respectively. The lower end of the segment.
The drill body according to claim 1, wherein a cutting portion is provided at a lower end of the hollow drill rod, and the cutting portion comprises:

A drill tip formed with a cutting edge; and

At least one turn of a spiral wing disposed on the outer peripheral surface of the hollow drill rod and close to the drill tip;

Wherein, the spiral wing forms a continuous cutting edge on a radial end face near the drill tip;

Alternatively, the spiral wing is provided with a plurality of detachable shovel teeth on a radial end surface near the drill point.
The drill body according to claim 5, wherein the drill point is provided with at least two spiral cutting edges around the central axis, and each of the spiral cutting edges is spaced around the central axis of the central drill rod. .
The drill body according to claim 1, wherein a plurality of stirring blades are arranged on the outer peripheral wall of the hollow drill pipe at intervals, and the maximum rotation diameter of the stirring blade around the center axis of the hollow drill pipe is less than or equal to the hollow drill pipe. Maximum drilling diameter of the rod.
The drill body according to claim 7, wherein each two to five stirring blades are arranged around a central axis of the hollow drill rod to form a radial stirring blade group, and each radial stirring blade group is along the hollow drill rod. The central axis is arranged at intervals;

Alternatively, each of the stirring blades is spirally arranged around an outer peripheral wall of the drill pipe.
The drill body according to claim 7 or 8, characterized in that the stirring blade is arranged obliquely with respect to the cross section of the hollow drill rod.
The drill body according to claim 3, further comprising: a power device for driving the hollow transmission shaft to rotate; and a power device axially sleeved on the upper shaft section of the hollow transmission shaft and supporting the power device on the top. Rigid outer tube

The output shaft of the power unit is axially connected to the upper shaft segment, and the bottom of the rigid outer tube and the upper shaft segment are movably connected by a sliding sleeve or a bearing;

At least one radial channel is opened on the peripheral surface of the upper end of the rigid outer tube, and an annular groove communicating with the radial channel is formed on the inner peripheral wall of the rigid outer tube;

The hollow transmission shaft is provided with a radial hole that communicates with its own axial center hole and the annular groove;

Alternatively, the output shaft has an axial hole communicating with a shaft center hole in the hollow transmission shaft, and the output shaft is provided with a radial hole communicating with the annular groove and the axial hole;

Alternatively, the rigid outer tube and the power unit are connected by a cylindrical object. An inner circumferential wall of the cylindrical object is provided with an annular groove, and the diameter of the cylindrical object is radially connected to the outer peripheral wall and the annular groove. Directional hole, the output shaft penetrating the cylindrical object has an axial hole communicating with the central hole of the hollow transmission shaft, and the output shaft is provided with a radial hole communicating with the annular groove and the axial hole .