CN102896366A

CN102896366A - Four-tip and eight-edge drill bit without chisel edge

Info

Publication number: CN102896366A
Application number: CN2012103862190A
Authority: CN
Inventors: 蔡晓双; 於星; 孙重阳
Original assignee: Suzhou Industrial Park Institute of Vocational Technology
Current assignee: Suzhou Industrial Park Institute of Vocational Technology
Priority date: 2012-10-12
Filing date: 2012-10-12
Publication date: 2013-01-30

Abstract

The invention discloses a four-tip and eight-edge drill bit without a chisel edge. A drill bit body adopts a three-tip and seven-edge basic gang drill bit; a V-shaped groove is ground between two arc edges of the basic gang drill bit, namely the position of the original chisel edge along a plane in the counterclockwise direction at 25 to 28 degrees and in the axial direction perpendicular to the edges; two inner cutting edges are formed on two sides of the V-shaped groove; and one chisel edge is ground away, so that the four-tip and eight-edge drill bit without the chisel edge is formed. With the adoption of the four-tip and eight-edge gang drill edge type, when fragile metal material is drilled, the operation difficulty is reduced and the drilling technologic scope is expanded, and therefore, the working efficiency can be improved.

Description

Four sharp eight swords without the chisel edge drill bit

Technical field

The present invention relates to a kind of drill bit, particularly a kind of four sharp eight swords of the Machining Brittle metal material that can use at common driller, numerical control drilling machine and boring machine without the chisel edge drill bit.

Background technology

Existing high speed steel twist drill head, its main body comprises cutter hub and cutter head, cutter hub is provided with spiral goove as chip area, its cutting tip comprises the cutting edge of two symmetries on the cutter head, be chisel edge between the symmetrical cutting edge, resistance main in drilling is from chisel edge, and therefore efficient is low when the Machining Brittle metal material.

Existing basic multi-facet drill is tricuspid seven swords, and speed of its cutting brittle metal material improves 2～3 times with respect to above-mentioned common fluted drill, but its chisel edge compares the chisel edge of common fluted drill and will lack, but still has resistance.

Summary of the invention

Goal of the invention of the present invention is in order to overcome the shortcoming of above-mentioned background technology, provide a kind of simple and direct and easy operating, and Machining Brittle metal material efficient to be high, and is improved without chisel edge four sharp eight cutting drill heads on the basic multi-facet drill drill bit.

Technical scheme of the present invention is as follows: a kind of four sharp eight swords without the chisel edge drill bit, its drill main body is the basic multi-facet drill drill bit of tricuspid seven swords, be that counterclockwise 25～28 degree and axial perpendicular blade grind a V-shaped groove along the plane at former chisel edge place between two Circular Nose Cutting Edges of this basic multi-facet drill drill bit, two trough rims of V-type groove form two interior cutting edges, grind off a chisel edge, form four sharp eight swords without the chisel edge drill bit.

Angle between described two interior cutting edges is 85～95 degree.

The degree of depth of described V-type groove is 15%～20% of basic multi-facet drill bit diameter length value.

The invention has the beneficial effects as follows: the present invention is by grinding off chisel edge, form two interior cutting edges, eliminated the resistance that chisel edge forms in the working angles, when the Machining Brittle metal material, reduce operation easier, expanded the processing range of drilling, significantly improved operating efficiency.

Description of drawings

Fig. 1 is front view of the present invention;

Fig. 2 is top view of the present invention;

Wherein: a, wedge angle one, b, wedge angle two, c, wedge angle three, d, wedge angle four, L1, outside, L2, arc sword, L3, inner edge, L4, interior cutting edge, R, the V-type angle of the v-groove, φ, bit diameter.

The specific embodiment

Present embodiment as shown in Figure 1 and Figure 2 be a kind of four sharp eight swords without the chisel edge drill bit, between two Circular Nose Cutting Edges of the basic multi-facet drill drill bit of tricuspid seven swords be former chisel edge place along the plane counterclockwise 25 degree and axially perpendicular blade grind a V-shaped groove, two trough rims of V-type groove form two interior cutting edges, grind off a chisel edge, form four sharp eight swords without the chisel edge drill bit.

Four wedge angles shown in Fig. 1 front view are wedge angle one (a), wedge angle two (b), wedge angle three (c), wedge angle four (d), outside (L1), arc sword (L2), the inner edge (L3) in drill bit left side, four swords of interior cutting edge (L4), the drill bit right side also has four swords symmetrical with the left side, forms like this eight swords.

Angle between described two interior cutting edges is that the angle of V-shaped groove (R) is 90 degree.

The degree of depth of described V-type groove be basic multi-facet drill bit diameter (φ) length value 15%～20%.

The process of described V-type groove is 25 ° of oblique angles that the chisel edge center of basic multi-facet drill is turned clockwise along the emery wheel side as shown in Figure 2, and up and down the radial feed sharpening into about 90 ° of angles.

Take 20 millimeters high speed steel twist drills of diameter as example, on the basis of basic multi-facet drill tricuspid seven swords, the chisel edge sharpening of former drill bit is become angle as depicted in figs. 1 and 2 and forms four sharp eight swords, because former chisel edge has become two oblique swords and has participated in cutting, under the guide-localization of drill bit at drill bushing, in drilling HT20-40 cast iron part, rotation speed n=115～220r/min, amount of feeding f=2.2mm/n, axial force descends significantly, the former basic multi-facet drill amount of feeding is less than 1.5 mm/n, and efficient of the present invention improves 1.5～2 times than former basic multi-facet drill.

Claims

1. sharp eight swords without the chisel edge drill bit, its drill main body is the basic multi-facet drill drill bit of tricuspid seven swords, be that counterclockwise 25～28 degree and axial perpendicular blade grind a V-shaped groove, two interior cutting edges of two trough rims formation of V-type groove along the plane at former chisel edge place between two Circular Nose Cutting Edges of this basic multi-facet drill drill bit.

According to claim 1 four sharp eight swords without the chisel edge drill bit, it is characterized in that angle between described two interior cutting edges is 85～95 degree.

According to claim 1 four sharp eight swords without the chisel edge drill bit, the degree of depth that it is characterized in that described V-type groove is 15%～20% of basic multi-facet drill bit diameter length value.