CN214023646U

CN214023646U - Asymmetric back-pull type tooth crown drill bit

Info

Publication number: CN214023646U
Application number: CN202022344223.3U
Authority: CN
Inventors: 蒋长青; 欧望达; 卜新荣; 沈秋波; 范羽; 殷亚军
Original assignee: Suzhou Ahno Precision Cutting Technology Co ltd
Current assignee: Suzhou Ahno Precision Cutting Technology Co ltd
Priority date: 2020-10-20
Filing date: 2020-10-20
Publication date: 2021-08-24
Anticipated expiration: 2030-10-20

Abstract

The utility model discloses an asymmetric back pull formula crown drill bit, inside main cooling hole of establishing of drilling rod, run through inside neck and stalk portion, two exports are seted up at the working part left end face in main cooling hole, form Y type structure, the working part is equipped with helicla flute and back of a knife blade, the entity part that the helicla flute was removed in the working part is the back of a knife blade, the helicla flute cross-section adopts U type groove, establish protection sword arris in the helicla flute, drilling rod left end face both sides are equipped with the locating surface that is used for crown tool bit location, left-handed internal thread hole is seted up to front end central part in the working part, locking screw one end screw in left-handed internal thread is downthehole and its other end is connected with the crown tool bit, fasten the crown tool bit on the drilling rod through locking screw. The utility model provides an asymmetric back pull formula crown drill bit, locking screw left end, right-hand member adopt the right-hand left-hand rotation, simple to operate, can not become flexible in the course of working, and tool bit assembly precision is high, and it is very firm to press from both sides tightly, and tool bit installation zero clearance, the general type of drilling is strong, under the poor condition of operating mode, also can use.

Description

Asymmetric back-pull type tooth crown drill bit

Technical Field

The utility model belongs to the technical field of accurate high-efficient metal cutting tool, concretely relates to draw formula crown drill bit behind asymmetry.

Background

The crown bit is a combined bit formed by a head and a drill rod, the head is made of hard alloy or other high-performance materials, the drill rod is made of alloy steel materials, and the crown bit is suitable for machining large-diameter holes and has the advantages of low use cost, large machining range and the like. At present, the head part of the crown drill bit and a drill rod have a plurality of combination modes, but most of the crown drill bits have complex structures, low tool bit assembly precision and high manufacturing cost.

SUMMERY OF THE UTILITY MODEL

For solving the technical problem that exists among the prior art, the utility model aims to provide an asymmetric back-pull type crown drill.

In order to realize the above purpose, reach above-mentioned technological effect, the utility model discloses a technical scheme be:

the utility model provides an asymmetric back pull formula crown drill bit, including drilling rod, crown tool bit and back pull formula locking screw, the drilling rod includes the work portion, neck and the stalk portion that connect gradually from left to right, inside the seting up main cooling hole of drilling rod, run through inside neck and the stalk portion, two exports are seted up at the work portion left end face in main cooling hole, form Y type structure, the work portion is equipped with helicla flute and back of a knife blade, the entity portion that the work portion removed the helicla flute is the back of a knife blade, the helicla flute cross-section adopts U type groove, be equipped with the protection sword arris in the helicla flute, work portion left end face both sides form the locating surface that is used for crown tool bit location, the levogyration internal thread hole is seted up to the front end in the work portion, locking screw one end screw in levogyration internal thread and its other end are connected with the crown tool bit, through locking screw with the detachable fastening of crown tool bit on the drilling rod.

Furthermore, the left end of the locking screw is provided with a right-handed thread matched with the crown bit, and the right end of the locking screw is provided with a left-handed external thread matched with the left-handed internal thread hole.

Furthermore, the outer diameter of the left end of the locking screw is smaller than that of the right end of the locking screw.

Furthermore, the contact position of the two sides of the left end face of the working part and the tooth crown cutter head is provided with a positioning surface, the positioning surface adopts an obtuse angle design, and the obtuse angle is 100-154 degrees.

Furthermore, the stalk portion is the cylinder structure, and the stalk portion top is equipped with oblique side pressure face, and oblique side pressure face is nonparallel with the drilling rod axis.

Furthermore, the included angle between the inclined lateral pressure surface of the handle part and the central axis of the drill rod is 2 degrees.

Compared with the prior art, the beneficial effects of the utility model are that:

the utility model discloses an asymmetric back-pull type tooth crown drill bit, which adopts a central back-pull type locking screw to lock, a wrench screws a drill rod and a tooth crown tool bit together by screwing the locking screw, the tensioning force is large, the installation is reliable, and the drill bit cannot be loosened in the processing process; the left end and the right end of the locking screw are respectively provided with a right-handed thread and a left-handed external thread with different turning directions, which are respectively matched with the crown bit and the drill rod, and the left-handed and right-handed locking screw is designed to be left-handed and right-handed, so that the installation is more convenient, and the locking screw cannot be loosened in the machining process; the matching precision of the left-handed inner threaded hole in the center of the drill rod and the locking screw is high, so that the cooling liquid is effectively prevented from leaking from the center, and the cooling effect is prevented from being influenced; the positioning surfaces on the upper side and the lower side of the left end of the drill rod are positioned by adopting an obtuse angle design, the angle is 100-154 degrees, and the positioning reliability is high; the area of the drill rod supporting part is large, and the supporting strength is high; the drill rod is made of high-strength alloy steel, so that the drill rod is high in strength, good in wear resistance, good in shock resistance and long in service life; a main cooling hole structure with a Y-shaped outlet is adopted, so that cooling liquid is conveniently provided; the spiral groove adopts a U-shaped groove structure, the drill rod has good rigidity, can bear large-feed processing and is not easy to break, and the design of the protective knife edge effectively prevents the drill rod from being broken due to the fact that the front knife face of the drill rod participates in cutting and extrusion; the left end of the drill rod is provided with a supporting surface, so that an effective supporting effect is achieved during drilling and machining, and drilling is stable; the handle part is provided with an inclined lateral pressing surface which forms an included angle of 2 degrees with the central axis of the drill rod, and after the drill rod is installed and locked, the drill bit is prevented from being loosened due to axial displacement in the machining process; overall structure is simple, and tool bit assembly precision is high, and it is very firm to press from both sides tightly, and tool bit installation zero clearance, drilling general type are strong, under the poor condition of operating mode, also can use.

Drawings

Fig. 1 is a schematic perspective view of the present invention;

fig. 2 is a schematic cross-sectional view of the present invention;

3-5 are respectively the three-dimensional structure schematic diagrams of the drill rod of the utility model;

FIG. 6 is a schematic cross-sectional view of a drill rod according to the present invention;

fig. 7 is a cross-sectional view taken along line a-a of fig. 6 in accordance with the present invention;

fig. 8 is a cross-sectional view taken along line B-B of fig. 6 in accordance with the present invention;

fig. 9 is a schematic perspective view of the crown bit of the present invention;

fig. 10 is a schematic cross-sectional view of a crown bit of the present invention;

fig. 11 is a cross-sectional view taken along line C-C of fig. 10 in accordance with the present invention;

fig. 12 is a cross-sectional view taken along line D-D of fig. 10 in accordance with the present invention;

fig. 13 is a schematic view of the flute, back and edge of the crown bit of the present invention;

fig. 14 is a schematic structural view of the main blade, the inner blade and the transition blade of the crown bit of the present invention;

fig. 15 is a schematic structural view of a locking screw according to the present invention;

fig. 16 is a schematic structural view of the assembled drill rod, crown bit and locking screw of the present invention.

Detailed Description

The embodiments of the present invention are described in detail below to make the advantages and features of the present invention easier to understand by those skilled in the art, thereby making more clear and definite definitions of the protection scope of the present invention.

As shown in fig. 1-16, an asymmetric back-pull type crown drill bit comprises a drill rod 1, a crown bit 2 and a back-pull type locking screw 3, wherein the crown bit 2 is detachably fastened on the drill rod 1 through the back-pull type locking screw 3, the drill rod 1 is a coaxial cylinder formed by a working part 5, a neck part 10 and a handle part 11 which are sequentially connected from left to right and take the same central axis as the center, a left-handed internal thread hole 7 is formed in the center of the left end of the drill rod 1, a right-handed thread 20 matched with the crown bit 2 is arranged at the left end of the locking screw 3, a left-handed external thread 21 matched with the left-handed internal thread hole 7 is arranged at the right end of the locking screw 3, the outer diameters of the left and right ends of the locking screw 3 are different, the outer diameter of the left end is small, the outer diameter of the right end is large, during assembly, the left-handed external thread 21 at the right end of the locking screw 3 is screwed into the left-handed internal thread hole 7, the crown bit 2 is connected together through the right-handed thread 20 on the locking screw 3, the spanner passes through the main cooling hole 13 to tighten the locking screw 3, and then the crown bit 2 is tightly fixed on the drill rod 1.

Main cooling hole 13 is seted up at the inside middle part of drilling rod 1, run through work portion 5, neck 10 and stalk portion 11 are inside, two exports 14 are seted up at the left end face of work portion 5 in main cooling hole 13, provide the coolant liquid for crown bit 2 at the during operation, main cooling hole 13 forms Y type structure with two exports 14, external spanner can pass main cooling hole 13 and screw up or loosen the locking screw 3 in the levogyration internal thread hole 7, and then realize crown bit 2 and drilling rod 1 whether locking.

The supporting surface 6 is arranged on the outer side of the left end face of the drill rod 1, obtuse positioning surfaces 17 are arranged at the contact positions of the upper side and the lower side of the left end face of the drill rod 1 and the tooth crown tool bit 2 and used for positioning the tooth crown tool bit 2, the obtuse design is adopted on the positioning surfaces 17, the value range of an included angle 16 formed by the positioning surfaces 17 is 100-154 degrees, the positioning surfaces 17 on the two sides are not centrosymmetric and are eccentrically arranged with a left-handed inner threaded hole 7, the eccentricity 15 is 0.05-0.3mm, the area of the supporting part of the drill rod 1 is large, and the supporting strength is high.

Work portion 5 is equipped with spiral helicine helicla flute 8 and back of a knife 9, helicla flute 8 plays appearance bits and chip removal effect at the during operation, the entity portion that removes helicla flute 8 on the work portion 5 is called back of a knife 9, the design of U type groove 19 is adopted in the 8 cross-sections of helicla flute, adopt the design of U type groove 19, it is big to hold the bits space, the chip removal is smooth and easy, back of a knife 9 intensity is also high simultaneously, the feed rate is fast during processing, be equipped with protection arris of a knife 18 in the helicla flute 8, the partial groove anterior angle of external diameter has been reduced, prevent that abominable operating mode drilling rod 1 from participating in the cutting and leading to the disconnected sword.

The neck 10 is a combination of a left end cone and a right end cylinder and is used for connecting the working part 5 and the handle part 11, so that chips can be prevented from splashing to impact the handle part 11 and a machine tool spindle during working, and a protection effect is achieved.

The shank 11 is a section of cylinder with high circular precision, an inclined side pressing surface 12 is arranged on the cylinder (the outer side of the top), an included angle between the inclined side pressing surface 12 and the central axis of the drill rod 1 is 2 degrees, the inclined side pressing locking screw is used for locking, the shank 11 is clamped by the tool holder during use to transmit power of a machine tool, so that the drill bit rotates to have cutting capacity, and cooling liquid of a cooling system of the machine tool can be transmitted to the tool through a main cooling hole 13 formed in the central axis of the shank 11.

As a specific embodiment, the crown bit 2 is provided with a cylindrical surface 35, a bottom surface 36, a central hole 37, an apex angle 38 and a locking thread 39, the crown bit 2 is positioned by two obtuse angle positioning surfaces 311 and locked by a steel wire thread sleeve 310, the locking screw 3 locks the crown bit 2 on the drill rod 1, the crown bit 2 mainly plays a role of drilling and cutting and ensures the precision of processing holes, the cylindrical surface 35 is positioned at the outer edge of the crown bit 2, the bottom surface 36 is arranged perpendicular to the central axis of the drill rod 1, the locking thread 39 is arranged in the central hole 37, the steel wire thread sleeve 310 is sleeved in the locking thread 39 and used for locking the crown bit 2, the two sides of the crown bit 2 are ground to respectively form the obtuse angle positioning surfaces 311, the obtuse angle positioning surfaces 311 are provided with clearance surfaces 312, the central lines of the obtuse angle positioning surfaces 311 at the two sides are arranged eccentrically to the central line of the central hole 37, the solid part of the crown bit 2 except the chip discharge groove 117 is a back 115, the intersection surface of the chip groove 117 and the back 115 in the radial direction forms an edge 116, the guide surface 114 is used for installation and guide, when the crown bit 2 is installed, the crown bit is self-guided into the drill rod 1, when the vertex angle 38 is ground, a flank face 318 and a chisel edge 319 are automatically formed, the flank face 318 can reduce friction during drilling and machining, the chisel edge 319 plays a centering role, the chip groove 320 is ground to form a main edge 322 and an inner edge 321, a transition edge 323 is formed between the main edge 322 and the inner edge 321, and the flank face 318, the chisel edge 319, the main edge 322, the inner edge 321 and the transition edge 323 form the whole cutting edge.

During manufacturing, the bottom surface 36 is ground, the crown bit 2 is locked through the wire thread insert 310 by taking the bottom surface 36 as a reference, the vertex angle 38 is ground, and then the cylindrical surface 35 is ground by taking the vertex angle 38 and the central hole 37 as references.

The obtuse angle positioning surfaces 311 on the two sides of the crown bit 2 are ground, the center lines of the obtuse angle positioning surfaces 311 on the two sides of the crown bit 2 and the center line of the central hole 37 are eccentrically arranged, the eccentricity 313 is 0.02-0.2 mm, the obtuse angle positioning surfaces 311 on the two sides are designed to be obtuse angles, the included angle formed by the two sides of each obtuse angle positioning surface 311 is 100 plus 154, each obtuse angle positioning surface 311 is provided with a clearance avoiding surface 312, and the crown bit 2 can conveniently enter the drill rod 1 in a self-guiding manner during installation.

And grinding the cylindrical surface parts of the chip grooves 117 and the grinding back 115 to form edges 116, wherein the spiral angle alpha of the chip grooves 117 is 0-35 degrees.

Grinding the top angle 38 to form a flank face 318, grinding the flank face 318 and the chip groove 320 to form a main edge 322 and an inner edge 321, forming a transition edge 323 between the main edge 322 and the inner edge 321, wherein the length of the inner edge 321 is 1/4-1/2 of the length of the main edge 322, and the arc size of the transition edge 323 is R0.1-3 mm.

The size of centre bore 37 is 0.2 ~ 1mm, and the centre bore angle is 60.

The pitch of the locking thread 39 is M2-12.

The utility model discloses the part of not specifically describing adopt prior art or product can, do not do here and describe repeatedly.

The above only is the embodiment of the present invention, not limiting the patent scope of the present invention, all the equivalent structures or equivalent processes that are used in the specification and the attached drawings or directly or indirectly applied to other related technical fields are included in the patent protection scope of the present invention.

Claims

1. The utility model provides an asymmetric back pull formula crown drill bit, a serial communication port, including drilling rod, crown bit and back pull formula locking screw, the drilling rod includes work portion, neck and the stalk portion that connects gradually from left to right, inside the seting up main cooling hole of drilling rod, run through inside neck and the stalk portion, two exports are seted up at the work portion left end face to main cooling hole, form Y type structure, the work portion is equipped with helicla flute and back of a knife blade, the entity portion that the helicla flute was removed to the work portion is the back of a knife blade, the helicla flute cross-section adopts U type groove, be equipped with the protection arris in the helicla flute, work portion left end face both sides form the locating surface that is used for crown bit location, left-handed internal thread hole is seted up to the front end in the work portion, locking screw one end screw in left-handed internal thread hole and its other end are connected with the crown bit, fasten the crown bit on the drilling rod detachably through locking screw.

2. The asymmetric back-pull type crown drill according to claim 1, wherein a right-handed thread adapted to the crown bit is provided at the left end of the locking screw, and a left-handed external thread adapted to the left-handed internal thread hole is provided at the right end of the locking screw.

3. The asymmetric back pull crown drill bit according to claim 1, wherein the locking screw has a smaller outer diameter at the left end than at the right end.

4. The asymmetric back-pull type crown drill according to claim 1, wherein the positions of both sides of the left end surface of the working portion, which are in contact with the crown bit, are provided with positioning surfaces, and the positioning surfaces are designed to form an obtuse angle, and the obtuse angle is 100-154 degrees.

5. The asymmetric back-pull crown bit according to claim 1, wherein the shank is cylindrical, and the top of the shank is provided with an inclined side pressing surface which is not parallel to the central axis of the drill rod.

6. The asymmetric back pull crown drill bit as claimed in claim 5, wherein the angle between the inclined flank of the shank and the central axis of the drill rod is 2 °.