AU2019330308B2

AU2019330308B2 - Drill body

Info

Publication number: AU2019330308B2
Application number: AU2019330308A
Authority: AU
Inventors: Zhaodi ZHOU
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-08-31
Filing date: 2019-07-29
Publication date: 2022-02-03
Anticipated expiration: 2039-07-29
Also published as: AU2019330308A1; CN110872838A; WO2020042846A1; ZA202102137B

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 CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims priority to Chinese Patent Application No. 201811010914.0 with the title of "DRILL BODY", filed on August 31, 2018, the content

of which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] The present disclosure relates to the field of pile foundation construction, and in particular, to a drill body for constructing the pile foundation.

BACKGROUND

[0003] Cement-soil mixing pile is a method for reinforcing saturated soft clay

foundation. In the cement-soil mixing pile, cement is used as a curing agent, and soft soil

and the curing agent are forcedly mixed in a predetermined depth of the foundation by a

special mixing machine. Then, the soft soil is hardened into a foundation with high quality,

integrity, water stability and predetermined strength through a series of physical and

chemical reactions between the soft soil and the curing agent.

[0004] When an existing pile machine performs cement-soil mixing pile constructing operations, a drill rod is provided with a slurry discharge port at a lower end thereof to

spray cement slurry during drilling. In this case, the cement slurry cannot be stirred when

the drill rod is reversed and retracted, which results in non-uniform stirring, thereby

affecting overall structural strength of the cement-soil mixing pile.

[0005] In view of the above, in the related art, a cement-soil mixing pile device is

provided to alternately spray the cement slurry in an upward direction and a downward

direction. The cement-soil mixing pile device includes a drill rod, combined slurry feed

pipes disposed within the drill rod and axially sequentially communicated with each other, and a gas control valve. The drill rod is provided with an upper slurry spray port and a lower slurry spray port at a side wall thereof that are communicated with the slurry feed pipes respectively. The air control valve controls switching of communications between the upper slurry spray ports, the lower slurry spray port and the combined slurry feed pipes through inflation and deflation.

[0006] Although the cement-soil mixing pile device as described above can achieve the slurry spraying at a bottom portion of the drill rod when the drill rod drills in the

downward direction and achieve the slurry spraying at an upper portion of the drill rod

when the drill rod is lifted upwardly, the switching of the communications between the

upper slurry spray port, the lower slurry spray port and the combined slurry feed pipes is

manually controlled by operating a control switch of the air control valve to achieve the

operation control. Therefore, the cement-soil mixing pile device has poor automation.

SUMMARY

[0007] An object of the present disclosure is to solve the problem that switching of

communications between an upper nozzle and a lower nozzle of an existing drill rod cannot

be automatically controlled.

[0008] In order to achieve the above object, there is provided a drill body including a hollow transmission shaft and a hollow drill rod that is sleeved axially outside the hollow

transmission shaft and rotates along with the hollow transmission shaft. The hollow

transmission shaft has an axial length greater than an axial length of the hollow drill rod.

The hollow transmission shaft is axially provided with an upper discharge port and a lower

discharge ports that are spaced apart from each other, and the hollow drill rod is axially

provided with an upper nozzle and a lower nozzle that are spaced apart from each other.

The hollow drill rod is axially reciprocable relative to the hollow transmission shaft. The

lower discharge port and the lower nozzle are communicated with each other when the drill

body drills, and the upper discharge port and the upper nozzle are communicated with each

other when the drill body is retracted.

[0009] Further, in the drill body according to some embodiments of the present disclosure, a spacing between the upper nozzle and the lower nozzle is defined as a first distance LI, a spacing between the upper discharge port and the lower discharge port is defined as a second distance L2, an opening size of the upper discharge port is defined as a diameter D, and a sum of the second distance L2 and the diameter D is equal to the first distance Li. The hollow drill rod is axially provided with a waist-shaped hole, a stop rod passing through the waist-shaped hole is radially installed on the hollow transmission shaft, and a reciprocating distance of the stop rod in the waist-shaped hole is equal to the diameter D.

[0010] Further, in the drill body according to some embodiments of the present disclosure, the hollow transmission shaft includes an upper shaft segment and a lower shaft segment that are axially connected to each other. An output shaft of the power device is axially connected to the upper shaft segment. The hollow drill rod is axially sleeved outside the lower shaft segment of the hollow transmission shaft, and the upper discharge port and the lower discharge port are disposed in the lower shaft segment of the hollow transmission shaft and spaced apart from each other. An outer circumferential wall of the lower shaft segment has at least one flat surface, and the hollow drill rod is axially provided with a profiling bore on a top end surface of the hollow drill rod to be fitted with the lower shaft segment.

[0011] Further, the drill body according to some embodiments of the present disclosure further includes an elastic element disposed within the profiling bore. Two ends of the elastic element abuts against a bottom portion of the profiling bore and a lower end of the lower shaft segment, respectively.

[0012] Further, in the drill body according to some embodiments of the present disclosure, the hollow drill rod is provided with a cutting portion at a lower end thereof. The cutting portion includes a drill tip formed with at least one cutting edge and at least one spiral wing disposed on an outer circumferential surface of the hollow drill rod close to the drill tip. The at least one cutting edge is formed to be a continuous cutting edge on a radial end surface of the spiral wing close to the drill tip. Alternatively, a plurality of

'I detachable shovel teeth is arranged on the radial end surface of the spiral wing close to the drill tip.

[0013] Further, in the drill body according to some embodiments of the present disclosure, the drill tip is provided with at least two spiral cutting edges around a central axis of the hollow drill rod. The at least two spiral cutting edges are spaced apart from each other around the central axis of the hollow drill rod.

[0014] Further, in the drill body according to some embodiments of the present disclosure, a plurality of stirring blades is arranged on an outer circumferential wall of the hollow drill rod and spaced apart from each other, and a maximum rotation diameter of the plurality of stirring blades around a central axis of the hollow drill rod is less than or equal to a maximum drilling diameter of the hollow drill rod.

[0015] Further, in the drill body according to some embodiments of the present disclosure, every two to five stirring blades of the plurality of stirring blades are arranged around the central axis of the hollow drill rod to form a radial stirring blade group, and all the radial stirring blade groups are spaced apart from each other along the central axis of the hollow drill rod. Alternatively, the plurality of stirring blades is arranged spirally around the outer circumferential wall of the hollow drill rod.

[0016] Further, in the drill body according to some embodiments of the present disclosure, the plurality of stirring blades is arranged obliquely with respect to a cross section of the hollow drill rod.

[0017] Further, the drill body according to some embodiments of the present disclosure further includes a power device for driving the hollow transmission shaft to rotate and a rigid outer tube axially sleeved outside the upper shaft segment of the hollow transmission shaft and supporting the power device at a top thereof. An output shaft of the power device is axially connected to the upper shaft segment, and a bottom portion of the rigid outer tube is movably connected to the upper shaft segment by a slidable sleeve or a bearing. At least one radial channel is provided in an upper circumferential surface of the rigid outer tube, and an annular groove communicating with the at least one radial channel is formed in an inner circumferential wall of the rigid outer tube.

A

[0018] Further, in the drill body according to some embodiments of the present disclosure, the hollow transmission shaft is provided with a radial hole to communicate a shaft bore of the hollow transmission shaft and the annular groove of the rigid outer tube. Alternatively, the output shaft has an axial bore communicating with the shaft bore of the hollow transmission shaft, and the output shaft is further provided with a radial hole to communicate the annular groove of the rigid outer tube and the axial bore. Alternatively, the rigid outer tube is connected to the power device by a cylinder, an inner circumferential wall of the cylinder is provided with an annular groove, the cylinder is further radially provided with a radial hole to communicate an outer circumferential wall and the annular groove of the cylinder, and the output shaft passes through the cylinder, and the output shaft is provided with a radial hole to communicate the annular groove of the cylinder and the axial bore of the output shaft.

[0019] The drill body of the present disclosure allows the hollow drill rod to axially reciprocate relative to the hollow transmission shaft. When the drill body drills, the hollow drill rod moves axially and upwardly relative to the hollow transmission shaft under an action of a resistance of an object to be cut, so that the upper discharge port and the upper nozzle are isolated from each other and the lower discharge port and the lower nozzle are communicated with each other. At this time, a fluid can be sprayed through the lower nozzle to an area to be drilled. When the drill body is retracted, the hollow drill rod moves axially and downwardly relative to the hollow transmission shaft due to a self-weight of the hollow drill rod, so that the lower discharge port and the lower nozzle are isolated from each other and the upper discharge port and the upper nozzle are communicated with each other. At this time, the fluid is sprayed through the lower nozzle to a stirring area. With this structure, when the drill body drills or is retracted, the fluid can be sprayed through the lower nozzle or the upper nozzle as desired without manual switching of communication modes, so that the drill body can realize uniform stirring to ensure an overall structural strength in the cement-soil mixing pile.

BRIEF DESCRIPTION OF DRAWINGS

[0020] FIG. 1 is a perspective view of a drill body according to a first embodiment of the present disclosure;

[0021] FIG. 2 is a front view of the drill body according to the first embodiment of the present disclosure;

[0022] FIG. 3 is a schematic structural view of a lower shaft segment according to the first embodiment of the present disclosure;

[0023] FIG. 4 is an axial sectional view of a hollow drill rod according to the first embodiment of the present disclosure;

[0024] FIG. 5 is an axial sectional view of the drill body according to the first

embodiment of the present disclosure;

[0025] FIG. 6 is an enlarged view of a part corresponding to a portion indicated by A shown in FIG. 5;

[0026] Fig. 7 is an enlarged view of a part corresponding to a portion indicated by B

shown in FIG. 5;

[0027] FIG. 8 is a schematic view of an assembly of a hollow drill rod and a lower

shaft segment according to a second embodiment of the present disclosure;

[0028] FIG. 9 is a schematic view of an internal structure of a drill body at a top portion of a rigid outer tube according to a third embodiment of the present disclosure; and

[0029] FIG. 10 is a schematic view of an internal structure of a drill body at a top

position of a rigid outer tube according to a fourth embodiment of the present disclosure.

[0030] Reference List

100: drill body; 1. hollow transmission shaft; 11. upper shaft segment; 12. lower shaft segment;

121. upper discharge port; 122. lower discharge port; 123. flat surface; 124. stop rod; 13.

shaft bore; 14. radial hole; 15. shaft hub;

2. power device; 21. output shaft; 211. axial bore; 212. radial hole;

3. hollow drill rod; 31. upper nozzle; 32. lower nozzle; 33. profiling bore; 34.

cutting portion; 341. drill tip; 342. spiral wing; 343. cutting edge; 344. shovel teeth; 35.

K2 stirring blade; 36. waist-shaped hole; 4. elastic element; 5. rigid outer tube; 51. radial channel; 52. annular groove; 6. sealing body; 7. arc-shaped cover; 71. inclined wedge surface; 72. fastener; 8. slidable sleeve; 9. cylinder; 91. annular groove; 92. radial hole.

DESCRIPTION OF EMBODIMENTS

[0031] Embodiments of the present disclosure will be clearly and completely described hereinafter with reference to the accompanying drawings in order to make objections, technical solutions and advantages of some embodiments of the present disclosure clearer. It should be understood that the embodiments described below are merely some of, rather than all of the embodiments of the present disclosure.

First Embodiment

[0032] As shown in FIGS. 1, 2 and 5, a drill body 100 according to some embodiments of the present disclosure is suitable for pile foundation construction in a cement-soil mixing pile. The drill body 100 includes a hollow transmission shaft 1, a power device 2, a hollow drill rod 3, and a rigid outer tube 5.

[0033] As shown in FIGS. 1 and 2, the hollow drill rod 3 is provided with a cutting portion 34 at a lower end thereof. 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. Further, the spiral wing 342 is disposed on an outer circumferential surface of the hollow drill rod 3 close to the drill tip 341. The spiral wing 342 is fixed to the hollow drill rod 3 by welding. A plurality of detachable shovel teeth 344 is arranged on a radial end surface of the spiral wing 342 close to the drill tip 341. In the drill body 100 according to some embodiments of the present disclosure, the cutting edge may be formed to be a continuous cutting edge on the radial end surface of the spiral wing 342 close to the drill tip 341.

[0034] As shown in FIGS. 1 and 2, in some embodiments of the present disclosure, the drill tip 341 is provided with at least two spiral cutting edges 343 with a spiral angle in a

range from 5° to 850 around a central axis of the hollow drill rod 3, and the spiral cutting

edges 343 are spaced apart from each other around the central axis of the hollow drill rod

3. The drill tip 341 and a rod body of the hollow drill rod 3 are fixed to each other by

welding. Alternatively, the hollow drill rod 3 and the drill tip 341 are screwed and fixed to

each other by a fastener (not shown), or the hollow drill rod 3 and the drill tip 341 are

axially screwed and fixed to each other.

[0035] As shown in FIGS. 1 and 2, a plurality of stirring blades 35 is arranged on an outer circumferential wall of the hollow drill rod 3 at an interval. The stirring blades 35

extend radially and outwardly from the outer circumferential wall of the hollow drill rod 3.

The plurality of stirring blades 35 (not shown) may also be uniformly distributed on the

rigid outer pipe 5. Further, a maximum rotation diameter of the stirring blades 35 around

the central axis of the hollow drill rod 3 is less than or equal to a maximum drilling diameter

of the hollow drill rod 3. In this way, the stirring blades 35 is capable of fully and uniformly

stirring a solid-liquid mixture or object that has been cut into debris.

[0036] As shown in FIG. 2, in some embodiments of the present disclosure, 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 all of the radial mixing blade groups are arranged at

intervals along the central axis of the hollow drill rod 3. When a plurality of drill bodies

100 with similar structures are combined for the pile foundation construction, such

structural design can avoid mutual interference between the drill bodies 100.

[0037] As shown in FIGS. 1 and 2, each of the stirring blades 35 is arranged obliquely

with respect to a cross section of the hollow drill rod 3, in order to reduce an axial

movement resistance of the drill body 100 when the drill body 100 drills or is retracted.

Specifically, a length direction of each stirring blade 35 is perpendicular to an axial

direction of the hollow drill rod 3, and a blade surface of the stirring blade 35 is inclined to

the central axis of the hollow drill rod 3.

[0038] In the drill body 100 according to some embodiments of the present disclosure,

for a single operating drill body 100, or a combined drill body composed of the plurality

Q of drill bodies 100 with similar structures for the pile foundation construction, when a distance between every two adjacent drill bodies 100 is sufficiently large and/or when rotation speeds and rotation directions of the drill bodies 100 are consistent, the stirring blades 35 may also be arranged spirally around the outer circumferential wall of the hollow drill rod 3.

[0039] As shown in FIGS. 3 to 5, the hollow transmission shaft 1 has an axial length greater than that of the hollow drill rod 3. The hollow transmission shaft 1 includes an upper shaft segment 11 and a lower shaft segment 12. Further, the hollow transmission shaft 1 is axially provided with an upper discharge port 121 and a lower discharge port 122 that are spaced apart from each other. In some embodiments of the present disclosure, the upper discharge port 121 and the lower discharge port 122 are disposed in the lower shaft segment 12 and spaced apart from each other. In addition, the hollow drill rod 3 is axially provided with an upper nozzle 31 and a lower nozzle 32 that are spaced apart from each other. The hollow transmission shaft 1 moves downwardly and axially relative to the hollow drill rod 3 during drilling, such that the lower discharge port 122 and the lower nozzle 32 are communicated with each other and the upper discharge port 121 and the upper nozzle 31 are isolated from each other. The hollow transmission shaft 1 moves upwardly and axially relative to the hollow drill rod 3 during retraction, such that the upper discharge port 121 and the upper nozzle 31 are communicated with each other and the lower discharge port 122 and the lower nozzle 32 are isolated from each other.

[0040] As shown in FIGS. 3 to 5, specifically, the power device 2 is configured to drive the hollow transmission shaft 1 to rotate. The upper shaft segment 11 and the lower shaft segment 12 are axially connected to each other by a shaft hub 15 and simultaneously rotate as one part. As shown, an output shaft 21 of the power device 2 is axially connected to the upper shaft segment 11 by the shaft hub. Further, the hollow drill rod 3 can axially reciprocate relative to the hollow transmission shaft 1.

[0041] As shown in FIGS. 3 to 5, the hollow drill rod 3 is axially sleeved outside the hollow transmission shaft 1 and rotates along with the hollow transmission shaft 1. Specifically, the hollow drill rod 3 is axially sleeved outside the lower shaft segment 12 of the hollow transmission shaft 1. An outer circumferential wall of the lower shaft segment

12 has at least one flat surface 123, and the hollow drill rod 3 is axially provided with a profiling bore 33 on a top end surface thereof to befitted with the lower shaft segment 12. This structure can prevent the hollow drill rod 3 from circumferentially rotating relative to the hollow transmission shaft 1.

[0042] As shown in FIGS. 3 to 5, in some embodiments of the present disclosure, a spacing between the upper nozzle 31 and the lower nozzle 32 is defined as a first linear distance LI, a spacing between the upper discharge port 121 and the lower discharge port 122 is defined as a second linear distance L2, and an opening size of the upper discharge port 121 is defined as a diameter D. A sum of the second linear distance L2 and the diameter D is equal to the first linear distance LI, in order to ensure that the lower discharge port 122 and the lower nozzle 32 are fully communicated with each other during drilling and the upper discharge port 121 and the upper nozzle 31 are fully communicated with each other during retraction.

[0043] As shown in FIGS. 5 and 6, in order to prevent the hollow drill rod 3 from axially separating from the hollow transmission shaft 1 when the drill body 100 is retracted, the hollow drill rod 3 is axially provided with a waist-shaped hole 36, and a stop rod 124 passing through the waist-shaped hole 36 is radially installed on the lower shaft segment 12. The stop rod 124 axially reciprocates relative to the hollow transmission shaft 1 along with the hollow drill rod 3. That is, the stop rod 124 and the waist-shaped hole 36 are combined to form an anti-separation device. However, a reciprocating distance of the stop rod 124 in the waist-shaped hole 36 should be equal to the diameter D of the upper discharge port 121. This size can ensure that the lower discharge port 122 and the lower nozzle 32 are fully communicated with each other when the drill body drills, and the upper discharge port 121 and the upper nozzle 31 are fully communicated with each other when the drill body is retracted.

[0044] As shown in FIGS. 5 and 6, in order to prevent debris from entering the waist shaped hole 36 to affect the reciprocating movement of the stop rod 124 during the pile foundation construction, an arc-shaped cover 7 may be further installed on the stop rod 124 and attached to the outer circumferential wall of the hollow drill rod 3. The arc-shaped cover 7 moves synchronously with the stop rod 124. Further, the arc-shaped cover 7 can

11) effectively cover the waist-shaped hole 36, regardless of a position of the stop rod 124 at either end of the waist-shaped hole 36. In some embodiments of the present disclosure, the arc-shaped cover 7 and the stop rod 124 are detachably connected to each other by a fastener 72. With such a structure, even if some small debris enter the waist-shaped hole

36, the arc-shaped cover 7 can be removed for regular cleaning and maintenance.

[0045] As shown in FIGS. 5 and 6, in some embodiments of the present disclosure, both end portions of the arc-shaped cover 7 are formed into inclined wedge surfaces 71 in

an axial direction of the drill body 100. That is, the both end portions of the arc-shaped

cover 7 have cutting edges formed by the inclined wedge surfaces 71. Such structure can

remove the debris or the solid-liquid mixture with viscous substance attached to the outer

circumferential wall of the hollow drill rod 3 while the arc-shaped cover 7 reciprocates.

[0046] As shown in FIGS. 2, 5 and 7, in this embodiment, the rigid outer tube 5 is axially sleeved outside the upper shaft segment 11 of the hollow transmission shaft 1 and

supports the power device 2 at a top thereof. A bottom of the rigid outer tube 5 and the

upper shaft segment 11 are movably connected to each other by a slidable sleeve 8, so that

the upper shaft segment 11 is rotatable freely relative to the rigid outer tube 5. Specifically,

the rigid outer tube 5 is connected to the power device 2 by a cylinder 9. An inner

circumferential wall of the cylinder 9 is provided with an annular groove 91. The cylinder

9 is radially provided with a radial hole 92 for communicating an outer circumferential

wall of the cylinder 9 and the annular groove 91. Furthermore, the output shaft 21 passing

through the cylinder 9 has an axial bore 211 communicated with a shaft bore 13 of the

hollow transmission shaft 1, and the output shaft 21 is provided with a radial hole 212 to

communicate the annular groove 91 and the axial bore 211.

[0047] As shown in FIGS. 2, 5 and 7, a small radial gap is formed between the output

shaft 21 of the power device 2 and the cylinder 9 to ensure that the output shaft 21 can

rotate freely relative to the cylinder 9. The cylinder 9 is provided with sealing bodies 6 at

both axial sides of the annular groove 91, in order to prevent a fluid (a gas or a cement

slurry) from entering to interfere normal operation of the power device 2 and freedom of

the movement of the hollow drive shaft 1 relative to the rigid outer tube 5. Further, the

cylinder 9 may be provided with one or more sealing bodies, and the sealing bodies 6 may be different from each other in material and structure.

[0048] As shown in FIGS. 2, 5 and 7, with the structure as described above, when the drill body 100 drills, the fluid (the gas or the cement slurry) sequentially flows through the radial hole 92, the annular groove 91, the radial hole 212, the axial bore 211, the shaft bore 13 and the lower discharge port 122, and then is transported to the lower nozzle 32 to be discharged out of the drill body 100. When the drill body 100 is retracted, the fluid (the gas or the cement slurry) sequentially flows through the radial hole 92, the annular groove 91, the radial hole 212, the axial bore 211, the shaft bore 13 and the upper discharge port 121, and then is transported to the upper nozzle 31 to be discharged out of the drill body 100.

[0049] As shown in FIG. 2, in some embodiments of the present disclosure, when the drill body 100 drills, the fluid discharged from the drill body 100 through the lower nozzle 32 is the cement slurry. When the drill body 100 is retracted, the fluid discharged from the drill body 100 through the upper nozzle 31 is the gas such as a compressed air. In the drill body 100 according to the embodiments of the present disclosure, the fluid discharged from the drill body 100 through the upper nozzle 31 or the lower nozzle 32 is the cement slurry when the drill body 100 drills or when the drill body 100 is retracted.

Second Embodiment

[0050] A second embodiment of the present disclosure will be described hereinafter. In this embodiment, the same parts as in the first embodiment are indicated by the same reference numerals, and the detailed description thereof will be omitted herein.

[0051] The drill body 100 according to the second embodiment of the present disclosure has a different structure described below as compared with the first embodiment. As shown in FIG. 8, the drill body 100 according to the second embodiment of the present disclosure further includes an elastic element 4. Specifically, the elastic element 4 is disposed within the profiling bore 33, and the elastic element 4 abuts against a bottom portion of the profiling bore 33 and a lower end of the lower shaft segment 12 at two ends thereof, respectively. Further, the elastic element 4 has an elastic deformation amplitude that is equal to or greater than the diameter D of the upper discharge port 121, in order to ensure effective operation of the elastic element 4. When the drill body 100 drills, the

11) elastic element 4 is compressed downwardly to be shortened axially by the hollow transmission shaft 1. In this case, the lower discharge port 122 communicates with the lower nozzle 32.

[0052] As compared with the first embodiment, the elastic element 4 is configured in

a manner that when the drilling body 100 is retracted, the elastic element 4 is axially

extended after removing an axial compression force exerted to the elastic element 4, and

then two ends of the elastic element 4 are urged against the bottom portion of the profiling

bore 33 and the lower end of the lower shaft segment 12, which facilitates the axial and

downward movement of the hollow drill rod 3 relative to the hollow transmission shaft and

allow for the communication between the upper discharge port 121 and the upper nozzle

31. In some embodiments of the present disclosure, the elastic element 4 may be a

compression spring. In the drill body 100 according to some embodiments of the present

disclosure, the elastic element 4 may also be an extendable elastic ring made of a material

with elastic properties such as polyurethane.

Third Embodiment

[0053] A third embodiment of the present disclosure will be described hereinafter. In

this embodiment, the same parts as in the first embodiment are indicated by the same

reference numerals, and the detailed description thereof will be omitted herein.

[0054] The drill body 100 according to the third embodiments of the present disclosure

has a different structure described below as compared with the first embodiment. As shown

in FIG. 9, the rigid outer tube 5 is formed with at least one radial channel 51 in an upper

circumferential surface thereof. The rigid outer tube 5 is further formed with an annular

groove 52 communicating with the radial channel 51 in an inner circumferential wall

thereof. In addition, the hollow transmission shaft 1 is provided with a radial hole 14 to

communicate the shaft bore 13 thereof and the annular groove 52.

[0055] With this structure, when the drill body 100 drills, the fluid (the gas or the

cement slurry) sequentially flows through the radial channel 51, the annular groove 52, the

radial hole 14, the shaft bore 13, and the lower discharge port 122, and then is transported

to the lower nozzle 32 to be discharged from the drill body 100. When the drill body 100

1'l is retracted, the fluid (the gas or the cement slurry) sequentially flows through the radial channel 51, the annular groove 52, the radial hole 14, the shaft bore 13, and the upper discharge port 121, and then is transported to the upper nozzle 31 to be discharged from the drill body 1000

[0056] As compared with the first embodiment, the drill body 100 according to the

third embodiment of the present disclosure is not provided with the cylinder 9, which

makes the drill body 100 more compact in structure.

Fourth Embodiment

[0057] A fourth embodiment of the present disclosure will be described hereinafter. In

[0058] The drill body 100 according to the fourth embodiments of the present disclosure has a different structure described below as compared with the first embodiment.

As shown in FIG. 10, the rigid outer tube 5 is formed with the at least one radial channel

51 in the upper circumferential surface thereof. The rigid outer tube 5 is further formed

with the annular groove 52 communicating with the radial channel 51 in the inner

circumferential wall thereof. In addition, the output shaft 21 is provided with the axial bore

211 communicating with the shaft bore 13 of the hollow transmission shaft 1, and the

output shaft 21 is further provided with the radial hole 212 to communicate the annular

groove 52 and the axial bore 211.

[0059] With this structure, when the drill body 100 drills, the fluid (the gas or the

is retracted, the fluid (the gas or the cement slurry) sequentially flows through the radial

channel 51, the annular groove 52, the radial hole 212, the axial bore 211, the shaft bore

13, and the upper discharge port 121, and then is transported to the upper nozzle 31 to be

discharged from the drill body 100.

[0060] As compared with the first embodiment, the drill body 100 according to the

1IA fourth embodiment of the present disclosure is not provided with the cylinder 9, which makes the drill body 100 more compact in structure.

[0061] The technical principle of the present disclosure has been described above in conjunction with some embodiments thereof. However, it should be noted that the foregoing description are merely used for explaining the principle of the present disclosure, and cannot be construed as a specific limitation on the scope of the present disclosure in any way. In view of this, other specific embodiments or equivalent substitutions made by those skilled in the art without departing from the scope of the present disclosure shall fall within the scope of the present disclosure.

Claims

Uni-Intel Ref DF210610AU

What is claimed is: 1. A drill body, comprising:

a hollow transmission shaft; and

a hollow drill rod sleeved axially outside the hollow transmission shaft and rotating along

with the hollow transmission shaft,

wherein the hollow transmission shaft has an axial length greater than an axial length of

the hollow drill rod, and the hollow transmission shaft is axially provided with an upper

discharge port and a lower discharge port that are spaced apart from each other;

wherein the hollow drill rod is axially provided with an upper nozzle and a lower nozzle

that are spaced apart from each other; and

wherein the hollow drill rod is axially reciprocable relative to the hollow transmission

shaft, and the lower discharge port and the lower nozzle are communicated with each other

when the drill body drills; and the upper discharge port and the upper nozzle are communicated

with each other when the drill body is retracted.
2. The drill body according to claim 1, wherein a spacing between the upper nozzle and

the lower nozzle is defined as a first distance (LI), a spacing between the upper discharge port

and the lower discharge port is defined as a second distance (L2), an opening size of the upper

discharge port is defined as a diameter (D), and a sum of the second distance (L2) and the

diameter (D) is equal to the first distance (LI); and

the hollow drill rod is axially provided with a waist-shaped hole, a stop rod passing through

the waist-shaped hole is radially installed on the hollow transmission shaft, and a reciprocating

distance of the stop rod in the waist-shaped hole is equal to the diameter (D).
3. The drill body according to claim 1, wherein the hollow transmission shaft comprises

an upper shaft segment and a lower shaft segment that are axially connected to each other;

the hollow drill rod is axially sleeved outside the lower shaft segment of the hollow

1K

Uni-Intel Ref DF210610AU

transmission shaft, and the upper discharge port and the lower discharge port are disposed in

the lower shaft segment of the hollow transmission shaft and spaced apart from each other; and

an outer circumferential wall of the lower shaft segment has at least one flat surface, and

the hollow drill rod is axially provided with a profiling bore on a top end surface of the hollow

drill rod to be fitted with the lower shaft segment.
4. The drill body according to claim 3, further comprising:

an elastic element disposed within the profiling bore, two ends of the elastic element

abutting against a bottom portion of the profiling bore and a lower end of the lower shaft

segment, respectively.
5. The drill body according to claim 1, wherein the hollow drill rod is provided with a

cutting portion at a lower end thereof, and the cutting portion comprises:

a drill tip formed with at least one cutting edge; and

at least one spiral wing disposed on an outer circumferential surface of the hollow drill rod

close to the drill tip,

wherein the at least one cutting edge is formed to be a continuous cutting edge on a radial

end surface of the spiral wing close to the drill tip; or

wherein a plurality of detachable shovel teeth is arranged on the radial end surface of the

spiral wing close to the drill tip.
6. The drill body according to claim 5, wherein the drill tip is provided with at least two

spiral cutting edges around a central axis of the hollow drill rod, and the at least two spiral

cutting edges are spaced apart from each other around the central axis of the hollow drill rod.
7. The drill body according to claim 1, wherein a plurality of stirring blades is arranged on

an outer circumferential wall of the hollow drill rod and spaced apart from each other, and a

maximum rotation diameter of the plurality of stirring blades around a central axis of the hollow

drill rod is less than or equal to a maximum drilling diameter of the hollow drill rod.

1-7

Uni-Intel Ref DF210610AU
8. The drill body according to claim 7, wherein every two to five stirring blades of the

plurality of stirring blades are arranged around the central axis of the hollow drill rod to form a

radial stirring blade group, and all the radial stirring blade groups are spaced apart from each

other along the central axis of the hollow drill rod; or

the plurality of stirring blades is arranged spirally around the outer circumferential wall of

the hollow drill rod.
9. The drill body according to claim 7 or 8, wherein the plurality of stirring blades is

arranged obliquely with respect to a cross section of the hollow drill rod.
10. The drill body according to claim 3, further comprising:

a power device for driving the hollow transmission shaft to rotate; and

a rigid outer tube axially sleeved on the upper shaft segment of the hollow transmission

shaft and supporting the power device at a top thereof,

wherein an output shaft of the power device is axially connected to the upper shaft segment,

and a bottom portion of the rigid outer tube is movably connected to the upper shaft segment

by a slidable sleeve or a bearing;

wherein at least one radial channel is provided in an upper circumferential surface of the

rigid outer tube, and an annular groove communicating with the at least one radial channel is

provided in an inner circumferential wall of the rigid outer tube;

wherein the hollow transmission shaft is provided with a radial hole to communicate a

shaft bore of the hollow transmission shaft and the annular groove of the rigid outer tube; or

wherein the output shaft has an axial bore communicating with the shaft bore of the hollow

transmission shaft, and the output shaft is further provided with a radial hole to communicate

the annular groove of the rigid outer tube and the axial bore; or

wherein the rigid outer tube is connected to the power device by a cylinder, an inner

circumferential wall of the cylinder is provided with an annular groove, the cylinder is further

radially provided with a radial hole to communicate an outer circumferential wall and the

annular groove of the cylinder, the output shaft passes through the cylinder, and the output shaft

is provided with a radial hole to communicate the annular groove of the cylinder and the axial

1Q

Uni-Intel Ref DF210610AU

bore of the output shaft.