CN103157834B

CN103157834B - Drill bit with low chisel edge

Info

Publication number: CN103157834B
Application number: CN201310104178.6A
Authority: CN
Inventors: 刘伟; 王弢; 蒋长青
Original assignee: SUZHOU AHNO CUTTING TOOL TECHNOLOGY Co Ltd
Current assignee: Suzhou Ahno Precision Cutting Technology Co., Ltd.
Priority date: 2013-03-28
Filing date: 2013-03-28
Publication date: 2015-03-25
Anticipated expiration: 2033-03-28
Also published as: CN103157834A

Abstract

The invention relates to a drill bit with a low chisel edge. The drill bit comprises a handle portion and a head portion, wherein the handle portion is a cylinder, the head portion is a coaxial cylinder which shares the same axis with the handle portion, two chip discharge grooves are formed in the head portion, a solid portion forming the chip discharge grooves is a knife back, intersecting lines of the two chip discharge grooves and the knife back in the axis direction respectively form two main cutting edges, intersecting lines of the two chip discharge grooves and the knife back in the radial direction form seamed edges, the seamed edges and the main cutting edges intersect to form a knife point, the chisel edge with 140-degree convexity is arranged between the two main cutting edges, and a sharp point of the chisel edge is 0.5-1mm lower than the knife point in the axis direction. Due to the chisel edge with the 140-degree convexity, knife strength is guaranteed, and meanwhile prominent centring capacity is guaranteed; the powerful centring capacity can inhibit bouncing and thereby guarantees long service life of a knife; and the drill bit is suitable for drilling machining for carbon fiber composite materials used for aviation.

Description

Low chisel edge drill bit

Technical field

The present invention relates to efficient high-speed precision cutting tool, particularly relate to a kind of low chisel edge drill bit for the processing of aviation carbon fibre composite, belong to optical, mechanical and electronic integration processing technique field.

Background technology

The processing difficulties be still in Field of Aviation Manufacturing processed by aviation carbon fibre composite, especially in hole machined, very easily occurs the manufacturing defect such as arch limit, layers of material, outlet burr, can cause part rejection time serious.At present, because carbide alloy has balanced physical property, higher toughness and wearability, be still the main cutting tools for cutting material in the processing of aviation carbon fibre composite.But how by the geometric angle of improvement of cutter, improve bore process rigidity and also reduce cutting resistance, then avoiding similar manufacturing defect, is current urgent problem.

Summary of the invention

The object of the invention is the deficiency overcoming prior art existence, a kind of low chisel edge drill bit is provided, be intended to the manufacturing issue such as arch limit, layers of material, outlet burr solving the appearance of aviation carbon fibre composite hole machined.

Object of the present invention is achieved through the following technical solutions:

Low chisel edge drill bit, comprise shank and head, shank is a cylinder, head is the coaxial clyinder of one and shank coaxial line, head has two chip areas, the entity part forming chip area is the knife back, and two chip areas and knife back intersection in the axial direction form two main cutting edges respectively, chip area and knife back intersection in radial directions forms seamed edge, and seamed edge is crossing with main cutting edge forms point of a knife; Feature is: the chisel edge arranging convexity 140 ° between two main cutting edges, at axis direction chisel edge cusp lower than point of a knife 0.5 ~ 1mm.

Further, above-mentioned low chisel edge drill bit, wherein, the angle that main cutting edge is formed is re-entrant angle in 120 °.

Further, above-mentioned low chisel edge drill bit, wherein, the angle that point of a knife is formed is 60 °.

Further, above-mentioned low chisel edge drill bit, wherein, is provided with protection cutter groove in described chip area.

Again further, above-mentioned low chisel edge drill bit, wherein, protection cutter groove is the protection cutter groove of negative 5 ~ 10 ° of anterior angles; The width of protection cutter groove is 0.8 ~ 1.0mm.

The substantive distinguishing features that technical solution of the present invention is outstanding and significant progress are mainly reflected in:

(1) chisel edge of convexity 140 ° both took into account tool strength, in turn ensure that comparatively outstanding centering ability, was applicable to the processing site adopting pneumatic tools; Stronger centering ability can suppress to beat, thus ensures longer cutter life;

(2) drill bit main cutting edge adopts re-entrant angle design in 120 °, makes axial force towards axis, avoids towards the axial force of hole wall, then avoids workpiece to encircle limit phenomenon;

(3) point of a knife of drill bit be designed to 60 ° very sharp, thus can cutting workpiece trippingly, then reduce layers of material and outlet burr;

The chisel edge of (4) 140 °, at axis direction lower than point of a knife 0.5 ~ 1mm, stably feels relieved on the one hand in cutting engineering, long owing to increasing actual sword on the other hand, improves the heat-sinking capability of drill bit, extends the bulk life time of cutter;

(5) in chip area, be provided with the protection cutter groove of negative rake, make it not participate in cutting, improve its guidance capability; Avoid causing " knife " phenomenon by the impact of excessive technological factor such as grade of beating in drilling process.

Accompanying drawing explanation

Below in conjunction with accompanying drawing, technical solution of the present invention is described further:

Fig. 1: the structural representation of the low chisel edge drill bit of the present invention;

Fig. 2: the schematic diagram of main cutting edge angle;

Fig. 3: the schematic diagram of point of a knife angle;

Fig. 4: the structural representation of chisel edge;

Fig. 5: the schematic diagram of protection cutter groove;

The B-B cross-sectional schematic of Fig. 6: Fig. 5.

Detailed description of the invention

The mentality of designing of the low chisel edge drill bit of the present invention improves the sharpness of drill bit, changes the processing mode that conventional drill chisel edge first contacts workpiece, change re-entrant angle in 120 ° into, avoid into radial load during brill by the convex drift angle of traditional design.Adopt the protection cutter groove of negative rake in drill bit rear end, to improve the stability of guiding, reduce drill bit seamed edge to the secondary cutting of workpiece, thus suppress workpiece to produce the tendency of arch limit and burr.

As shown in Figure 1, low chisel edge drill bit, comprise shank 1 and head 2, shank 1 is a cylinder, and head 2 is the coaxial clyinder of one and shank coaxial line, head has two chip areas 3, the entity part forming chip area is the knife back 4, two chip areas 3 are formed with two main cutting edges 5 with the knife back 4 intersection in the axial direction, and chip area 3 and the knife back 4 intersection in radial directions form seamed edge 6, and seamed edge 6 is crossing with main cutting edge 5 forms point of a knife 7; The chisel edge 8 of convexity 140 ° is set between two main cutting edges, as Fig. 4, at axis direction chisel edge cusp lower than point of a knife 0.5 ~ 1mm, stably can feel relieved in cutting engineering on the one hand, long owing to increasing actual sword on the other hand, improve the heat-sinking capability of drill bit, then significantly improve the bulk life time of cutter.Main cutting edge bears main drill tasks, and interior cutting edge intersects the chisel edge 8 forming convexity 140 ° and plays certralizing ability, reduces the circular runout in processing, and seamed edge 6 is for guiding, and the outside diameter that seamed edge is formed simultaneously is exactly bore diameter.In drilling engineering, first point of a knife 7 contacts workpiece, and is the operating position that the working time is the longest, linear velocity is maximum.

As shown in Figure 2, the angle that main cutting edge is formed is re-entrant angle in 120 °, makes axial force towards axis, avoids towards the axial force of hole wall, then can reduce workpiece arch limit phenomenon.

As shown in Figure 3, the angle that point of a knife is formed is 60 °, and point of a knife is very sharp, thus can then reduce layers of material and outlet burr by cutting workpiece trippingly.

As shown in Figure 5, be provided with protection cutter groove 9 in chip area, as shown in Figure 6, protection cutter groove is the protection cutter groove of negative 10 ° of anterior angles; The width of protection cutter groove is 0.8 ~ 1.0mm.Avoid causing " knife " phenomenon by the impact of excessive technological factor such as grade of beating in drilling process, by arranging the protection cutter groove of negative rake in chip area, making it not participate in cutting, improving its guidance capability.

Low chisel edge drill bit adopts whole hard alloy material, because it has higher hardness and wearability, is applicable to the processing characteristic of aviation carbon fibre composite.Usual selection ISO K05 ~ K10 trade mark, can select the trade mark of the good toughness such as ISO K30 ~ K40 when hole is comparatively dark or system of processing rigidity is poor.

Because low chisel edge drill bit belongs to efficient high-accuracy metal cutting tool, point of a knife and cutting edge are very sharp, conventional equipment easily produce microcosmic chipping and affects cutter life, must manufacturing in the contour rigid device of five axle CNC cutter and tool grinding machines, and amplifying Microscopic observation cutting edge state at 200 times.Crucial controlling dimension ensures the accuracy of manufacture by tolerance: main cutting edge indent 120 ° ± 1.5 °; Point of a knife angle 60 ± 1.5 °; Chisel edge convexity 140 ° ~ 137 °; Chisel edge is lower than point of a knife 0.5 ~ 1mm.

In sum, the low chisel edge drill bit of the present invention is applicable to the Drilling operation of aviation carbon fibre composite, by the optimization of geometry, the manufacturing defect such as arch limit, layers of material, outlet burr can be avoided, and can reach higher tool life by multiple auxiliary process means such as PVD coatings, application prospect is had an optimistic view of.

It is to be understood that: the above is only the preferred embodiment of the present invention; for those skilled in the art; under the premise without departing from the principles of the invention, can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims

1. low chisel edge drill bit, comprise shank and head, shank is a cylinder, head is the coaxial clyinder of one and shank coaxial line, head has two chip areas, the entity part forming chip area is the knife back, and two chip areas and the intersection of the knife back on the radial line direction of drill bit form two main cutting edges respectively, chip area and the intersection of the knife back on the axial direction of drill bit form seamed edge, and seamed edge is crossing with main cutting edge forms point of a knife; It is characterized in that: the chisel edge arranging convexity 140 ° between two main cutting edges, at axis direction chisel edge cusp lower than point of a knife 0.5 ~ 1mm, the angle that main cutting edge is formed is re-entrant angle in 120 °, and the angle that point of a knife is formed is 60 °.

2. low chisel edge drill bit according to claim 1, is characterized in that: be provided with protection cutter groove in described chip area.

3. low chisel edge drill bit according to claim 2, is characterized in that: the width of described protection cutter groove is 0.8 ~ 1.0mm.