CN111660444A - Drill bit - Google Patents

Abstract

The invention provides a drill bit and relates to the technical field of post-anchoring. The drill bit comprises a drill rod, wherein a groove extending along the axial direction of the drill rod is formed from one end of the drill rod to the opposite end of the drill rod, and the groove penetrates through the drill rod along the radial direction of the drill rod; the pushing piece comprises a connecting part and a base connected with the connecting part, and the connecting part can move in the groove along the axis direction; the plurality of blades are at least partially arranged in the groove and are adjacent to the connecting part, and the plurality of blades can move along the groove under the driving of the connecting part so as to protrude or retract into the drill rod; the thickness of the groove and the thickness of the blades increase along with the approach of the grooves to the axis, and the thickness of one end of the groove far away from the axis is smaller than that of one end of the blades close to the axis. The drill bit can effectively prevent the blade from easily sliding off the drill rod and falling off.

Description

Drill bit

Technical Field

The invention relates to the technical field of rear anchoring, in particular to a drill bit.

Background

The post-anchoring technology is to anchor on the existing concrete structure by related technical means, and mainly comprises mechanical anchor bolts, chemical anchor bolts, embedded bars and other technologies. The rear cutting bottom expanding type anchor bolt in the mechanical anchor bolt realizes the anchoring of the structure fixing piece through the mechanical interlocking between the cutting groove hole expanding at the bottom of the concrete drilling hole and the anchor bolt expansion head. The back-cut under-reamed anchor is divided into a self-grooving anchor and a pre-grooving anchor according to different grooving modes.

The relevant self-grooving crab-bolt is from taking the cutter, and self-grooving reaming, grooving installation once accomplish during the installation, but need use special drill bit to accomplish simultaneously reaming and two works of crab-bolt anchor from undercut crab-bolt, and the cost of this kind of crab-bolt is four times about ordinary expansion anchor. The related pre-grooving anchor bolt is reamed through pre-grooving by using a pre-grooving special drilling tool and then fixed by using a common anchor bolt. Some reaming drills adopt a gear and rack transmission mode to realize the expansion and contraction of the blade at the end part of the drill, and the reaming drill in the form has a complex structure and high manufacturing cost. The expansion and the shrink of blade are realized to the piece that resets in addition, though expand end drill bit simple structure, simple to operate, the cost is lower, but the restoring force that produces between the piece that resets on the one hand is difficult to adjust, and on the other hand once the piece that resets loses efficacy because of fatigue loss, the shrink and the expansion of blade will lose efficacy, lead to the blade easily to follow the drilling rod and slide and leave and drop, influence work efficiency.

Disclosure of Invention

In view of the above, the main objective of the present invention is to provide a drill bit to solve the problem that the blade of the bottom-expanding drill bit is easy to slip off the drill rod and fall off.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

the present invention provides a drill bit, comprising: the drilling rod is provided with a groove extending along the axial direction of the drilling rod from one end to the opposite end of the drilling rod, and the groove penetrates through the drilling rod along the radial direction of the drilling rod; the pushing piece comprises a connecting part and a base connected with the connecting part, and the connecting part can move in the groove along the axis direction; a plurality of blades, each blade being at least partially disposed within the recess and adjacent to the connecting portion, wherein the plurality of blades are movable along the recess under the influence of the connecting portion to protrude from or retract into the drill rod; wherein the thickness of the groove and the thickness of the plurality of blades increase with the approach of the axis, and the thickness of one end of the groove far away from the axis is smaller than that of one end of the plurality of blades close to the axis.

Further, the blade includes: a blade edge located at an outer edge of the blade; the knife back is positioned at the inner edge of the blade; the upper sliding surface is used for connecting one end of the cutting edge with one end of the knife back and is abutted with the groove; the lower sliding surface is connected with the other end of the cutting edge and the other end of the knife back, and the lower sliding surface is used for being abutted against the connecting part.

Further, the cutting edge includes first cutting edge and second cutting edge, the extending direction of first cutting edge with the contained angle that the extending direction of second cutting edge formed is greater than 0 degree and is less than 180 degrees.

Furthermore, the back of a knife includes first back of a knife and second back of a knife, the extending direction of upper sliding surface with the contained angle that the extending direction of lower sliding surface formed is greater than 0 degree and is less than 180 degrees.

Further, the pushing piece and the drill rod are coaxially arranged; wherein the thickness of the connecting part increases along with the approach of the axis, and the size of the connecting part is matched with that of the groove.

Furthermore, the connecting part is provided with a positioning groove which penetrates through the connecting part along the axis direction; the tail end of the drill rod is provided with a positioning hole penetrating through the drill rod along the radial direction; the drill bit further comprises a positioning pin, and the positioning pin is arranged in the positioning groove and the positioning hole to limit the movement of the connecting part.

Further, the connecting portion has a first contact surface and a second contact surface that abut against the insert, the first contact surface and the second contact surface being disposed symmetrically with respect to the axis.

Further, the connecting portion further has a third contact surface connecting the first contact surface and the second contact surface.

Further, the grooves are multiple and communicated with each other.

Further, the drill bit further comprises a slag containing groove which is arranged adjacent to the groove.

The drill bit comprises a drill rod, a pushing piece and a plurality of blades, wherein the thicknesses of the groove and the blades are increased along with the approach of the groove to the axis, and the thickness of one end of the groove far away from the axis is smaller than that of one ends of the blades close to the axis. According to the drill rod, the blade and the groove are of gradually-changed thickness, so that the blade can be clamped in the groove in the radial movement process of the blade along the groove, and the blade is effectively prevented from slipping off the drill rod and falling off.

Drawings

FIG. 1a is a schematic diagram of the working principle of a drill bit according to an embodiment of the present invention in one working state;

FIG. 1b is a schematic representation of the working principle of a drill bit according to an embodiment of the present invention in another working state;

FIG. 2a is a left side view of a shank configuration of a drill bit of an embodiment of the present invention;

FIG. 2b is a schematic cross-sectional view of FIG. 2a in the direction A-A;

FIG. 2c is a schematic cross-sectional view of FIG. 2B in the direction B-B;

FIG. 3a is a front view of a pusher configuration of a drill bit according to an embodiment of the present invention;

FIG. 3b is a left side view of the ejector structure of the drill bit according to the embodiment of the present invention;

FIG. 4 is a schematic view of an assembly of a drill rod and a pusher of a drill bit according to an embodiment of the present invention;

FIG. 5a is a schematic view of a drill bit according to an embodiment of the present invention in an operating state;

FIG. 5b is a schematic view of a drill bit according to an embodiment of the present invention in another operational state;

FIG. 6a is a schematic cross-sectional view in the direction C-C of FIG. 5 a;

FIG. 6b is a schematic cross-sectional view taken along line D-D of FIG. 5 b;

FIG. 7 is a schematic view of a blade configuration of a drill bit according to an embodiment of the present invention;

FIG. 8 is a top view of a pusher configuration of a drill bit according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of a groove structure of another drill bit;

FIG. 10 is a schematic view of an alternative insert configuration for a drill bit;

fig. 11 is a schematic structural view of a slag containing groove of the drill according to the embodiment of the present invention.

Description of reference numerals:

10-drill rod, 11-groove, 12-locating hole, 13-slag-containing groove, 14-slag guide groove, 20-pushing part, 21-connecting part, 211-locating groove, 212-first contact surface, 213-second contact surface, 214-third contact surface, 22-base, 30-blade, 31-blade, 311-first blade, 312-second blade, 32-back of blade, 33-upper sliding surface, 34-lower sliding surface, 40-locating pin, O' -central axis, X-horizontal symmetry axis, Y-vertical symmetry axis, theta-included angle formed by first blade and second blade, α -included angle formed by upper sliding surface and lower sliding surface, F-force applied by wall surface of construction object to first blade, F-slag guide groove, F-pushing part, 21-connecting part, 211-locating groove, 212-first contact surface, 213-second contact surface, 214-third contact surface, 22-base, 30-blade, 31-₁Horizontal component of force F, F₂Vertical component of force F, v speed of blade relative to first contact surface of connecting part, v₁The horizontal component of the velocity v, v₂Vertical component of velocity v, v' velocity of the blade relative to the groove, v₁Horizontal component of velocity v₂Vertical component of speed v

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The individual features described in the embodiments can be combined in any suitable manner without departing from the scope, for example different embodiments and aspects can be formed by combining different features. In order to avoid unnecessary repetition, various possible combinations of the specific features of the invention will not be described further.

In the following description, references to the term "first/second" merely distinguish between different objects and do not denote the same or a relationship between the two. It should be understood that the references to "above" and "below" are to be interpreted as referring to the orientation during normal use.

It should be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element. The term "coupled", where not otherwise specified, includes both direct and indirect connections. The term "plurality" means greater than or equal to two. The term "thickness" means the distance between two opposing faces of a sheet or block having a relatively large area.

The invention provides a drill bit which can be widely applied to the technical field of engineering and building construction as a rear anchoring tool, such as building beams, plates, columns, walls, brackets and the like. The processes of reinforcement, decoration, installation and the like are realized through drilling and/or reaming. It should be noted that the type of application scenario of the present invention does not limit the drill bit of the present invention.

The working principle of the drill bit is exemplified below in connection with fig. 1a and 1 b. The drill bit may include a drill rod 10, an ejector 20, and a blade 30. The drill rod 10 may be a generally cylindrical rod having a recess formed in one end for receiving the pusher 20 and the blade 30. The pusher 20 is movable along the recess relative to the drill rod 10 to move the blade 30 relative to the drill rod 10, the blade 30 having an expanded configuration and a contracted configuration. The blades 30 in the expanded state, in the radial direction of the drill rod 10, the distance between two points (or lines and/or faces) of two opposite blades 30 which are farthest away is greater than the outer diameter of the drill rod 10; the blade 30 in the retracted state is fully received in the recess. As shown in fig. 1a, the drill head extends to the surface of the construction object and is aligned with the region to be processed when the blade 30 is in the retracted state, the drill rod 10 starts to rotate at a high speed under the driving of an external machine, and the surface of the construction object is cut and ground by the end of the pushing member 20 of the drill head, thereby functioning as a lower probe drill head. Then, continuously extending the drill bit into the construction object until the preset depth, and finishing the processing of the straight hole, namely drilling, wherein the diameter of the straight hole is approximately the same as the outer diameter of the drill rod 10; when the blade 30 is switched from the contracted state to the expanded state as shown in fig. 1b, the part of the blade 30 protruding out of the drill rod 10 can continuously cut the wall surface of the straight hole contacted with the blade to realize reaming. After the reaming is completed, the blade 30 is switched from the expanded state to the contracted state, and the drill bit is lifted. The drill bit completes the whole process of drilling and reaming in the mode.

In an embodiment of the invention, as shown in fig. 1a and 1b, the drill bit comprises a drill rod 10, an ejector 20 and a plurality of blades 30. As shown in fig. 2a, a groove 11 extending along the axial direction of the drill rod 10 is opened from one end of the drill rod 10 to the opposite end, and the groove 11 penetrates through the drill rod 10 along the radial direction of the drill rod 10. In particular, the drill rod 10 is a generally cylindrical rod, the central axis O' of the cylinder being the axis. Along the direction of the central axis O ', the drill rod 10 is provided with a groove 11 extending from one end to the other end, as shown in the up-down direction of fig. 2a, the groove 11 extends upwards from the bottom end of the drill rod 10, and the groove 11 is of a symmetrical structure, and the symmetrical axis is the central axis O'. As shown in fig. 2b and 2c, the groove 11 extends through the drill rod 10 in the radial direction of the drill rod 10, so that the groove 11 communicates with the outside.

As shown in fig. 3a and 3b, the pusher 20 includes a connecting portion 21 and a base 22 connected to the connecting portion 21. Specifically, the connecting portion 21 may be a substantially plate-shaped object, and the base 22 may have various structures, such as a cone or a pyramid, that is, a structure with one end being sharp and the other end being round and blunt, so as to reduce the resistance of cutting the object, and effectively crush the region to be processed to form the hole. In an exemplary embodiment, the base 22 is a cone having a diameter substantially equal to the outer diameter of the drill rod 10, an end surface of the base 22 is connected to one end of the connecting portion 21, and the connecting portion 21 and the base 22 may be integrally formed or may be fixedly connected by welding, screwing, or the like.

As shown in fig. 4, the connecting portion 21 is movable in the axial direction within the recess 11. Specifically, the connecting portion 21 can be inserted into the groove 11 and move in the groove 11 along the direction of the central axis O' relative to the drill rod 10 to move the base 22. When the coupling 21 is moved to one end of the range of motion (the upper end as shown in fig. 4), the end surface of the seat 22 can contact the bottom end of the drill rod 10.

As shown in fig. 5a and 5b, each blade 30 is at least partially disposed within the recess 11 and adjacent to the connecting portion 21. Specifically, each insert 30 is arranged symmetrically about the central axis O', the structural shape of each insert 30 is substantially the same, the number of inserts 30 is arbitrary and may depend on the number of recesses 11, and an embodiment of the present invention employs one recess 11, and accordingly, two inserts 30 may be radially disposed. The blade 30 can be inserted into the recess 11 and abuts against one end of the connecting portion 21 remote from the base 22. It should be noted that abutting means that two members are in contact with each other and abut against each other to form close contact.

As shown in fig. 5a and 5b, the plurality of blades 30 can be moved along the groove 11 by the connecting portion 21 to protrude or retract into the drill rod 10. In particular, as shown in fig. 5a, the blades 30 are all located in the recess 11 when the drill bit is in a non-working state or in a state of drilling straight holes, i.e. the drill rod 10 is received. When the drill bit needs to perform a reaming operation, the pushing member 20 moves in a direction approaching the drill rod 10 along the central axis O' (as indicated by the arrow in fig. 5 a), the connecting portion 21 can push the blade 30 located in the groove 11 to move relative to the drill rod 10, and under the continuous pushing force of the connecting portion 21, an increasing portion of the blade 30 gradually protrudes out of the drill rod 10, and assumes an open state, i.e., the state shown in fig. 5 b. It should be noted that even in the extreme state of opening, the blades 30 may not fully protrude from the drill rod 10, and at least a portion of the blades 30 is located in the recess 11, and is connected to the connecting portion 21 and the recess 11, so as to prevent the blades 30 from falling off the drill rod 10, i.e., each blade 30 is at least partially disposed in the recess 11.

As shown in fig. 6a, the thickness of both the recess 11 and the plurality of blades 30 increases as one approaches the axis. The thickness is a distance between two opposite surfaces having a large area. As shown in fig. 6a, which is a cross-sectional view of the drill, X and Y are two axes of symmetry of the flutes 11 and the blades 30. The thickness of the groove 11 is the length of the cross section of the groove 11 in the vertical direction, and the thickness of the blade 30 is the length of the cross section of the blade 30 in the vertical direction. The length of the line of the cross section of the groove 11 coinciding with the axis of symmetry Y is the maximum thickness of the groove 11, and the length of the line of the cross section of the insert 30 coinciding with the axis of symmetry Y is the maximum thickness of the insert 30. The thickness of the groove 11 and the blade 30 is gradually reduced from the symmetry axis Y along the symmetry axis X. And the minimum thickness of the recess 11 is greater than the minimum thickness of the blade 30 so that the blade 30 can only protrude from the drill rod 10 when moving in the direction of the axis of symmetry X.

As shown in fig. 6b, the thickness of the end of the recess 11 remote from the axis is less than the thickness of the end of the plurality of blades 30 adjacent to the axis. Specifically, the minimum thickness of the groove 11 is smaller than the maximum thickness of the blade 30, and when the blade 30 moves along the direction of the symmetry axis X, the maximum thickness of the blade 30 cannot pass through the minimum thickness of the groove 11, so that the blade 30 can be clamped in the groove 11, and the blade is prevented from falling off the drill rod 10 when moving along the direction of the symmetry axis X.

According to the embodiment of the invention, the drill bit is provided with the drill rod, the pushing piece and the blades, the blades can move in the grooves formed in the drill rod, the thicknesses of the grooves and the blades are increased along with the approach of the grooves to the axis, and the thickness of one end of each groove far away from the axis is smaller than that of one end of each blade close to the axis. According to the drill rod, the blade and the groove are of gradually-changed thickness, so that the blade can be clamped in the groove in the radial movement process of the blade along the groove, and the problem that the blade is easy to slip off from the drill rod and fall off is effectively solved.

In some embodiments, as shown in FIG. 7, blade 30 includes a cutting edge 31, a back 32, an upper sliding surface 33, and a lower sliding surface 34. The cutting edge 31 is located at the outer edge of the blade 30. Specifically, the outer edge refers to an edge of the insert 30 away from the central axis O'. The blade 31 is used for cutting an object. The back 32 is located at the inner edge of the blade. Specifically, the inner edge refers to an edge of the insert 30 in a direction close to the central axis O'. The back 32 is also the largest part of the overall thickness of the insert 30, and provides good rigidity for the rotational cutting of the insert 30.

As shown in fig. 5b, the upper sliding surface 33 connects one end of the blade 31 with one end of the back 32, the upper sliding surface 33 being adapted to abut the recess 11. It should be noted that the abutment means that the two members are in contact with each other and abut against each other to form close contact. The upper sliding surface 33 is at an angle to the central axis O 'and the top surface of the groove 11 is at the same angle to the central axis O', so that the upper sliding surface 33 makes good contact with the top surface of the groove 11, allowing the upper sliding surface 33 to slide along the top surface of the groove 11. The lower sliding surface 34 connects the other end of the blade 31 and the other end of the back 32, and the lower sliding surface 34 is adapted to abut the connecting portion 21. Specifically, the angle formed by the lower sliding surface 34 and the central axis O 'is the same as the angle formed by the end surface of the connecting portion 21 and the central axis O', so that the lower sliding surface 34 can be brought into good contact with the end surface of the connecting portion 21, and the lower sliding surface 34 can slide along the end surface of the connecting portion 21.

By arranging the blades in a polygonal structure, some edges have a cutting function, some edges have a guiding function, and other edges have good rigidity performance. The functions of the cutter blade are clear, and the safety, reliability and practicability of the cutter blade are guaranteed.

In some embodiments, as shown in fig. 7, the blade 31 includes a first blade 311 and a second blade 312, and an angle θ formed by an extending direction of the first blade 311 and an extending direction of the second blade 312 is greater than 0 degree and less than 180 degrees. Specifically, when the drill rod 10 is lifted up after the reaming step is completed and the first blade 311 and the second blade 312 are attached to the wall surface of the hole to be worked, the wall surface of the hole applies a force F perpendicular to the wall surface of the first blade 311 to the first blade 311, and the force F can be decomposed into a first component force F in the horizontal and vertical directions₁And a second component force F₂. Wherein, waterFirst component F of force in the horizontal direction₁The blade can be retracted and received in the recess 11 of the drill rod 10. Only if the included angle theta is greater than 0 degree and less than 180 degrees, the first blade 311 can generate a horizontal component force F when the drill rod 10 is lifted₁To receive the blade 30 into the recess 11. The included angle formed by the first cutting edge and the second cutting edge is set to be larger than 0 degree and smaller than 180 degrees, so that when the drill bit needs to be lifted up after hole expansion is completed, the blade can be collected in the groove through the horizontal component force applied by the hole wall surface of the construction object to the cutting edges, and no external force needs to be contacted. The design avoids the need of additionally arranging a blade restoring piece to reset the blade, and saves the cost of the drill bit.

In some embodiments, as shown in FIG. 7, the direction of extension of upper sliding surface 33 forms an angle α with the direction of extension of lower sliding surface 34 that is greater than 0 degrees and less than 180 degrees, and in particular, as shown in FIG. 5b, both upper sliding surface 33 and lower sliding surface 34 are sloped such that the angle between the slopes is 0 degrees < α < 180 degrees, upper sliding surface 33 is the surface in direct contact with groove 11, and lower sliding surface 34 is the surface in direct contact with joint 21. joint 21 moves upwardly in a vertical direction, and blade 30 moves along the slope of joint 21 relative to joint 21 at a velocity v that can be resolved into a horizontal velocity component v₁And a vertical velocity component v₂(ii) a The blade 30, when sliding along the slope of the groove 11 at a velocity v', is able to generate a horizontal velocity component v₁' and vertical velocity component v₂' of a compound of formula I; wherein a vertical velocity component v₂With vertical velocity component v₂Equal and opposite in size, so that the blade 30 is not displaced in the vertical direction, with a horizontal velocity component v₁And a horizontal velocity component v₁The same direction allows the blade 30 to move horizontally outwards with respect to the drill rod 10, i.e. the blade 30 can protrude from the drill rod 10, and only with an angle of 0 < α < 180 can the blade 30 be forced horizontally outwards to protrude from the drill rod 10, by setting the angle formed by the upper and lower sliding surfaces to be greater than 0 and less than 180, the design of the ramp can be used as a guide to move the blade to protrude from the drill rod.

In some embodiments, as shown in fig. 5b, the pusher 20 is arranged coaxially with the drill rod 10. Specifically, the pushing member 20 is symmetrical about the central axis O ', so that the pushing member 20 can drive the plurality of blades 30 to synchronously move to protrude out of the drill rod 10 when moving along the central axis O', so that each blade 30 protrudes out as much as possible, thereby satisfying the uniformity of hole expansion. As shown in fig. 8, the thickness of the connecting portion 21 increases as approaching the axis, and the size of the connecting portion 21 matches the size of the recess 11. In particular, matching means that the thickness of the connecting portion 21 is approximately the same as the thickness of the groove 11, and can be adapted properly. The groove 11 and the connecting portion 21 may be in a clearance fit manner, so that the connecting portion 21 can be more easily inserted into the groove 11 and slide in the groove 11. Because the groove 11 and the connecting part 21 are thick in the middle and thin on two sides and the sizes of the groove 11 and the connecting part 21 are adaptive, the connecting part 21 cannot move in the groove 11 along the radial direction, and the connecting part 21 can be always centered with the drill rod 10 in the moving process without center deviation. The thickness of the groove limits the connecting part to move along the radial direction of the groove, so that the pushing piece can always keep centering movement with the drill rod, and the design is simple and ingenious.

In some embodiments, as shown in fig. 5a, the connecting portion 21 is opened with a positioning groove 211 penetrating the connecting portion 21 along the axial direction. Specifically, the positioning groove 211 extends from one end close to the base 22 to the other end opposite to the one end along the central axis O', and penetrates through the connecting portion 21 along the thickness direction of the connecting portion 21, and the width of the positioning groove 211 is much smaller than that of the connecting portion 21. Note that the width refers to a distance between two opposing faces of the members in a direction perpendicular to the center axis O'. The end of the drill rod 10 is provided with a positioning hole 12 in the radial direction through the drill rod 10. Specifically, the positioning hole 12 may be a substantially circular hole with a center located at the central axis O', the positioning hole 12 penetrates through the drill rod 10 along the radial direction of the drill rod 10, and the diameter of the positioning hole 12 is substantially the same as the width of the positioning groove 211. The drill further includes a positioning pin 40, and the positioning pin 40 is disposed in the positioning groove 211 and the positioning hole 12 to restrict the movement of the connection portion 21. Specifically, the length of the positioning pin 40 is greater than the length of the positioning hole 12, the connecting portion 21 is inserted into the groove 11, the positioning pin 40 passes through the positioning hole 12 and the positioning groove 211, so that the connecting portion 21 is movably connected with the drill rod 10, and when the connecting portion 21 moves to the other end (the lower end as shown in fig. 5 a) of the movement range relative to the drill rod 10, the positioning pin 40 can prevent the connecting portion 21 from completely separating from the drill rod 10. Through setting up constant head tank, locating hole and locating pin, play the effect of restriction connecting portion motion jointly, this cooperation connected mode is simple, easily installs and changes, and the cost is lower.

In some embodiments, as shown in fig. 5b, the connecting portion 21 has a first contact surface 212 and a second contact surface 213 abutting the insert 30, the first contact surface 212 and the second contact surface 213 being symmetrically arranged about the axis. Specifically, the first contact surface 212 and the second contact surface 213 are symmetrical with respect to the central axis O', the first contact surface 212 and the second contact surface 213 are in contact with the lower sliding surface 34 of the insert 30, and the symmetrical arrangement of the first contact surface 212 and the second contact surface 213 can push each insert 30 to move synchronously. The first contact surface and the second contact surface which are symmetrically arranged on the connecting part realize synchronous movement between the blades.

In some embodiments, as shown in fig. 5b, the connecting portion 21 further has a third contact surface 214 connecting the first contact surface 212 and the second contact surface 213. Specifically, the third contact surface 214 is perpendicular to the central axis O', and when the insert 30 is completely received in the recess 11, as shown in fig. 5a, an included angle at which the third contact surface 214 and the insert 30 overlap forms a vacant space, so as to prevent the top end of the connecting portion 21 from contacting the insert 30, and causing impact and damage to the insert 30. The damage of the intersection between the blades is effectively reduced by arranging the third contact surface.

In other embodiments, as shown in fig. 9, the grooves 11 are provided in plurality, and the grooves 11 communicate with each other. Specifically, the number of the grooves 11 is arbitrary, and may be one or multiple, and the greater the number of the grooves 11 is, the greater the difficulty of the process of the drill rod 10 is, and accordingly, the number of the grooves 11 can be flexibly set according to actual needs. As shown in fig. 10, the number of blades 30 corresponds to the number of recesses 11, and the more blades 30, the more efficient the drilling and reaming will be, but the higher the cost of the blades will be.

In some embodiments, as shown in fig. 11, the drill bit further comprises a slag receiving groove 13 disposed adjacent to the recess 11. Specifically, hold sediment groove 13 and set up in the drilling rod 10 surface near the one end of recess 11, the drill bit can produce the cutting disintegrating slag at the in-process of work, holds sediment groove 13 and is used for accepting the disintegrating slag, effectively reduces the disintegrating slag and falls into the hole bottom. Meanwhile, the drill bit further comprises a slag guide groove 14 communicated with the slag containing groove 13, the slag guide groove 14 is arranged at the other end, far away from the groove 11, of the drill rod 10 and is communicated with the outside, and broken slag can be discharged to the outside environment along a channel of the slag guide groove 14 by centrifugal force generated by high-speed rotation of the drill bit. The number of the slag containing grooves 13 and the slag guiding grooves 14 can be one or more, the shapes can be the same or different, and the structure can be linear or spiral.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention.

Claims (10)

1. A drill bit, comprising:

the drilling rod is provided with a groove extending along the axial direction of the drilling rod from one end to the opposite end of the drilling rod, and the groove penetrates through the drilling rod along the radial direction of the drilling rod;

the pushing piece comprises a connecting part and a base connected with the connecting part, and the connecting part can move in the groove along the axis direction;

a plurality of blades, each blade being at least partially disposed within the recess and adjacent to the connecting portion, wherein the plurality of blades are movable along the recess under the influence of the connecting portion to protrude from or retract into the drill rod;

wherein the thickness of the groove and the thickness of the plurality of blades increase with the approach of the axis, and the thickness of one end of the groove far away from the axis is smaller than that of one end of the plurality of blades close to the axis.

2. The drill bit of claim 1, wherein the blade comprises:

a blade edge located at an outer edge of the blade;

the knife back is positioned at the inner edge of the blade;

the upper sliding surface is used for connecting one end of the cutting edge with one end of the knife back and is abutted with the groove;

the lower sliding surface is connected with the other end of the cutting edge and the other end of the knife back, and the lower sliding surface is used for being abutted against the connecting part.

3. The drill bit of claim 2, wherein the cutting edge comprises a first cutting edge and a second cutting edge, and the extending direction of the first cutting edge forms an angle greater than 0 degrees and less than 180 degrees with the extending direction of the second cutting edge.

4. The drill bit of claim 2, wherein an angle formed by the direction of extension of the upper sliding surface and the direction of extension of the lower sliding surface is greater than 0 degrees and less than 180 degrees.

5. The drill bit of claim 1, wherein the pusher is disposed coaxially with the drill rod; wherein the thickness of the connecting part increases along with the approach of the axis, and the size of the connecting part is matched with that of the groove.

6. The drill bit as claimed in claim 5, wherein the connecting portion has a positioning groove formed therethrough along the axial direction; the tail end of the drill rod is provided with a positioning hole penetrating through the drill rod along the radial direction; the drill bit further comprises a positioning pin, and the positioning pin is arranged in the positioning groove and the positioning hole to limit the movement of the connecting part.

7. The drill bit of claim 2, wherein the connecting portion has first and second contact surfaces that abut the insert, the first and second contact surfaces being symmetrically disposed about the axis.

8. The drill bit of claim 7, wherein the connecting portion further has a third contact surface connecting the first contact surface and the second contact surface.

9. The drill bit of claim 1, wherein the recess is a plurality of recesses, each recess communicating with the other recess.

10. The drill bit of claim 1, further comprising a slag receiving groove disposed adjacent the recess.

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