CN117206575A - Double-spiral toothed strong chip breaking type flanging pagoda twist drill - Google Patents

Abstract

The invention provides a double-spiral chip-breaking type flanging pagoda twist drill with teeth, which comprises a handle and a blade part, wherein the blade part comprises a pagoda cutting blade part and a blade edge cutting blade part which are sequentially connected, the front end of the pagoda cutting blade part is provided with a pagoda center, the rear end of the pagoda center is provided with a multi-stage pagoda ladder, the top of the pagoda center is provided with two symmetrical main cutting edges, each main cutting edge is provided with at least one main cutting edge tooth, each stage of the multi-stage pagoda ladder is provided with a secondary cutting edge, and each secondary cutting edge is provided with at least one secondary cutting edge tooth to realize segmented cutting and independent chip breaking of each ladder. Each step is a small cutting edge, and teeth of each edge part can be meshed with cutting materials in the cutting process, so that concave-convex notches of the cutting edge and the materials to be cut can be formed on each edge during cutting, the cutting stability of the cutting edge is improved, and the service life of a cutter is prolonged.

Description

Double-spiral toothed strong chip breaking type flanging pagoda twist drill

Technical Field

The invention relates to the technical field of twist drills, in particular to a double-spiral toothed strong chip breaking flanging pagoda twist drill which is suitable for the field of machining ISO P-type, K-type and M-type metal material holes of automobiles, engineering machinery and the like.

Background

At present, the common high-speed steel tools in the field of hole processing are commonly used, and two types of drill bits are available on the market: the first common spiral twist drill has low processing efficiency and poor hole processing precision; second kind: the nose contains the drill point of tapering step type, and this type drill bit has certain advantage in efficiency than ordinary fluted drill, but the hole that the processing was come out can lead to hole surface quality to fail to meet the demands because of iron fillings discharge problem is poor, appears obvious step line, and the blade of each ladder receives the top influence of the axial taper angle that it formed, and the cutting allowance increases, and the iron skips is piled up fast in narrow ladder space and is made the blade wearing and tearing faster more easily, reduces cutter life, influences the punching accuracy.

Disclosure of Invention

The technical problems to be solved by the invention are as follows: in order to overcome the defects in the prior art, the invention provides the double-helix toothed strong chip breaking flanging pagoda twist drill.

The technical scheme adopted for solving the technical problems is as follows: the utility model provides a strong chip breaking formula turn-ups pagoda twist drill of double helix tooth, includes stalk portion and cutting edge, the cutting edge is including pagoda cutting edge and the cutting edge of cutting edge portion that connects gradually, the front end of pagoda cutting edge portion is equipped with the pagoda top, and the top of pagoda is equipped with multistage pagoda ladder, the top of pagoda is equipped with two main cutting edges of symmetry, every all be equipped with at least one main cutting edge tooth on the main cutting edge, all be equipped with the minor cutting edge on each level of multistage pagoda ladder, every all be equipped with at least one minor cutting edge tooth on the minor cutting edge. The handle part is a cylindrical handle capable of clamping, three clamping planes are arranged at the tail end of the handle part, and preferably, the pagoda ladder is at least four-stage.

The main cutting edge of the drill point part is provided with 1-2 arc-shaped main cutting edge teeth with concave structures in the radial direction according to the diameter, the main body of the head of the cutter is provided with stepped multi-stage pagoda stepped transition cutting edges with the diameters gradually increased from the top to the rear end, namely, auxiliary cutting edges, and the main cutting edge of each auxiliary cutting edge is provided with one auxiliary cutting edge tooth so as to realize the sectional cutting and independent chip breaking of each step. Each step is a small auxiliary cutting edge, and in the process of cutting chips, the auxiliary cutting edge teeth of each edge part can be meshed with cutting materials, so that concave-convex notch of the cutting edge and the materials to be cut can be formed by each edge during cutting, the cutting stability of the cutting edge is further improved, and the service life of a cutter is prolonged.

Preferably, the number of the main cutting edge teeth on each main cutting edge is two, namely a first main cutting edge tooth and a second main cutting edge tooth, and the number of the auxiliary cutting edge teeth on each auxiliary cutting edge is one.

Further, the depth h1 of the main cutting edge tooth is 0.02D, the width D1 of the main cutting edge tooth is 0.03D, the main cutting edge tooth is provided with an inward concave arc-shaped groove with a relief angle of 8 degrees in the radial direction, an intermittent cutting edge is formed, so that the special geometric shape of scrap iron is formed, the scrap iron state during cutting is changed, and the scrap iron is easier to bend, break and discharge.

Further, the front angle correction face with the angle of 3 degrees to 5 degrees is arranged in the direction of the front tool face of the main cutting edge, the radial correction depth h2 is 0.03D, the axial correction length D2 is 0.05D, and the radial curling flow direction of scrap iron is forcibly changed while the sharpness of the cutting edge is improved. Wherein D represents the blade diameter.

Further, the pagoda top is a compound multistage top structure, and the compound multistage top structure comprises a first top and a second top, wherein the second top is arranged at the front end of the first top, the vertex angle alpha 1 of the first top is 118 degrees+/-3 degrees, the vertex angle alpha 3 of the second top is 135 degrees+/-3 degrees, and a chip rolling groove is formed in the position of the vertex angle of the second top in a matched penetrating mode.

Further, the radial direction of the second center is provided with two radially symmetrical circular arc symmetrical relief surfaces and two chisel edge lines, the circular arc relief angle alpha 4 of the circular arc symmetrical relief surfaces is 20 degrees, and the angle alpha 5 between the chisel edge line and the center line of the drill edge is 55 degrees.

Further, the blade part is provided with a spiral chip groove extending along the length of the blade part, each stage of pagoda ladder and the spiral chip groove form a radial cutting blade part and an axial reinforcing connection part, the axial groove surface of the chip groove is connected with the circular arc rear blade surface of the tip to form a main cutting edge, the radial front blade surface of the chip groove is connected with the blade back to form a secondary cutting blade, and two edges of the blade back along the spiral direction are respectively provided with a cutting edge used for guiding and supporting.

Further, the helix angle alpha 2 of the spiral chip removal groove is 20 degrees to 30 degrees, and the chip removal groove is provided with a flanging.

Further, the chip groove has a taper structure with a small core thickness and a large back core thickness, and the core thickness increment of the cutting edge part of the pagoda is as follows: the core thickness increment of the cutting edge part of the cutting edge margin is 0.03-0.08mm in every 100mm length: 1.5-2.0mm per 100mm length.

Further, the edges of all cutting edges of the edge part are subjected to negative rake angle passivation, the uniformity of the negative rake angle passivation is within 0.005mm, and the width is 0.02mm.

The beneficial effects of the invention are as follows:

(1) The small top structure of the pagoda is used for accurately punching and positioning, positioning is performed before the traditional center drill is used for drilling, and the drilling position is improved.

(2) The pagoda is multi-stepped, the sectional type cutting is carried out, the cutting form of the whole cutting edge is changed, breaking type scrap iron is generated, radial and axial cutting forces are dispersed, cutting resistance of drilling is reduced, and the cutting force born by each radial cutting edge is ensured to be dispersed to each step through the reinforcing connection part, so that the rigidity is improved, and the stability of drilling is improved.

(3) The main cutting edge part is subjected to negative rake angle passivation strengthening treatment, so that the anti-collapse capacity and wear resistance of the cutting edge are enhanced, the service life of the drill bit is prolonged, and the cutting performance can be ensured to be stable under the condition of high-efficiency processing.

(4) The flanging chip groove mainly promotes chip removal smoothly matched with taper core thickness and has cutter rigidity, so that deformation is reduced when the cutter is subjected to high-rotation-speed large-feed punching.

(5) Tooth structure, fine solution iron fillings rupture's problem to can make coolant liquid fully flow to blade, cooling blade reduces cutting temperature, and the load that bores into when cooperation multi-step structure punches drops obviously, improves drilling stability and improves cutter life.

Drawings

The invention is further described below with reference to the drawings and examples.

Fig. 1 is a schematic structural view of the pagoda twist drill of the present invention.

Fig. 2 is a schematic cross-sectional view of fig. 1 A-A.

Fig. 3 is a schematic side view of the tip.

Fig. 4 is a schematic side view of the tip.

Fig. 5 is a schematic view of the structure of the primary apex.

Fig. 6 is a schematic view of a two-stage tip.

Fig. 7 is a schematic view of the core thickness.

In the figure: 1. shank, 2, blade, 3, clamping plane, 4, pagoda tip, 41, first tip, 42, second tip, 43, main cutting edge, 44, first main cutting edge tooth, 45, second main cutting edge tooth, 51, first pagoda step, 52, second pagoda step, 53, third pagoda step, 54, fourth pagoda step, 55, fifth pagoda step, 56, minor cutting edge, 57, minor cutting edge tooth, 6, circular arc symmetrical relief surface, 7, reinforcing engagement, 8, margin, 9, junk slot, 10, flanging, 11, land, 12, chip reeling slot, 13, core thickness.

Detailed Description

The present invention will now be described in detail with reference to the accompanying drawings. The figure is a simplified schematic diagram illustrating the basic structure of the invention only by way of illustration, and therefore it shows only the constitution related to the invention.

As shown in fig. 1 and 2, the double-spiral toothed strong chip breaking type flanging pagoda twist drill comprises a handle part 1 and a blade part 2, wherein the handle part 1 is a cylindrical cutter handle which can be clamped, and three clamping planes 3 are arranged at the tail end of the cutter handle. The blade part 2 comprises a tower cutting blade part and a margin cutting blade part which are sequentially connected, the front end of the tower cutting blade part is provided with a tower center 4, the rear end of the tower center 4 is provided with a plurality of stages of tower steps, and preferably, the tower steps are at least four stages, in this embodiment five stages, and are sequentially a first tower step 51, a second tower step 52, a third tower step 53, a fourth tower step 54 and a fifth tower step 55 from front to back. As shown in fig. 3, two symmetrical main cutting edges 43 are arranged at the top of the pagoda center 4, at least one main cutting edge tooth is arranged on each main cutting edge 43, a secondary cutting edge 56 is arranged on each stage of the multi-stage pagoda ladder, and at least one secondary cutting edge tooth 57 is arranged on each secondary cutting edge 56. Preferably, the number of main cutting edge teeth on each main cutting edge 43 is two, namely a first main cutting edge tooth 44 and a second main cutting edge tooth 45, and the number of auxiliary cutting edge teeth 57 on each auxiliary cutting edge 56 is one.

As shown in figure 1, the rake angle is increased, drilling is light and rapid, the axial resistance can be reduced by 35% -50%, the blade part 2 is provided with spiral chip grooves 9 extending along the length of the blade part, each stage of pagoda ladder and the spiral chip grooves 9 form radial cutting blade parts and axial reinforcing connection parts 7, the axial groove surfaces of the chip grooves 9 are connected with the circular arc rear blade surfaces of the tip to form main cutting edges 43, the radial front blade surfaces of the chip grooves 9 are connected with blade backs 11 to form auxiliary cutting edges 56, two edges of the blade backs 11 along the spiral direction are respectively provided with a blade margin 8 for guiding and supporting, in the embodiment, the difference between the blade margin 8 and the blade backs 11 is less than or equal to 0.10mm, and the difference between the two blade backs 11 is less than or equal to 0.10mm. The helix angle alpha 2 of the spiral chip groove 9 is 20 degrees to 30 degrees, preferably, the spiral chip groove 9 is a right spiral, the helix angle alpha 2 is 25 degrees, and the chip groove 9 is provided with a flanging 10. As shown in fig. 7, the chip groove 9 has a taper structure with a small core thickness 13 and a large core thickness 13, and the increment of the core thickness 13 of the cutting edge of the pagoda is: every 100mm length is 0.03-0.08mm, the increment of the core thickness 13 of the cutting edge part of the cutting edge is: 1.5-2.0mm per 100mm length. The increment of the core thickness 13 of the cutting edge part of the cutting edge refers to the increment of the diameter reverse taper of the working part of the drill, and the increment of the core thickness 13 of the cutting edge part of the cutting edge is the increment of the core thickness 13 of the working part of the drill towards the direction of the handle part 1. The cutting edges of all cutting edges of the edge part 2 are subjected to negative rake angle passivation, the uniformity of the negative rake angle passivation is within 0.005mm, and the width is 0.02mm.

As shown in fig. 5, the depth h1 of the tooth of the main cutting edge is 0.02D, the width D1 is 0.03D, and the tooth of the main cutting edge is provided with an inward concave arc groove with a relief angle of 8 ° in the radial direction, so that an intermittent cutting edge is formed to enable the scrap iron to form a special geometric shape, and further the state of the scrap iron during cutting is changed, so that the scrap iron is easier to bend, break and discharge. The front cutting surface direction of the main cutting edge 43 is a positive rake angle correction surface of 3 degrees to 5 degrees, the radial correction depth h2 is 0.03D, the axial correction length D2 is 0.05D, and the radial curling flow direction of the scrap iron is forcibly changed while the sharpness of the cutting edge is increased. Wherein D represents the blade diameter.

As shown in fig. 4 and fig. 6, the pagoda center 4 is a compound multistage center structure, and includes a first center 41 and a second center 42, the second center 42 is disposed at the front end of the first center 41, the vertex angle α1 of the first center 41 is 118 ° ± 3 °, the vertex angle α3 of the second center 42 is 135 ° ± 3 °, and the chip winding groove 12 is disposed in a position matching the vertex angles penetrating through the two centers. The second center 42 has two radially symmetrical circular arc symmetrical relief surfaces 6 and two chisel edge lines in the radial direction, the circular arc relief angle alpha 4 of the circular arc symmetrical relief surfaces 6 is 20 degrees, and the angle alpha 5 between the chisel edge line and the drill edge center line is 55 degrees.

The process is characterized in that: the existing high-speed steel cutter is basically subjected to slotting and sharpening processing by using a special machine, the processing conditions of the cutter are creatively integrated with a CNC grinding machine process according to the structural characteristics and the use requirements of the cutter, after the process of processing a spiral groove by using a conventional special machine is finished, NUMROTOPLUS cutter software is used for programming, a processing program is led into the CNC grinding machine, the sharpening of the bottom edge part and the processing of teeth are performed by using the CNC grinding machine, the tooth processing needs to control the tooth size, and the distribution of the teeth at different positions is positioned. The machining capability and precision of the general special machine cannot ensure the symmetry of teeth, and the accurate detection and positioning cannot be completed. The CNC five-axis grinding machine is matched with a single-crystal corundum grinding wheel (100 #) with the advantages of multifunction, high efficiency and high precision, and the edge part 2 and teeth are precisely ground. The single edging time of the existing special machine is 5min, the CNC machine tool is 3min higher than the special machine efficiency by 40%, and the machining cost is basically consistent.

Under different workpiece materials: can be matched with nano coating technology with different purposes. The surface layer covers the coating, and the service life of the cutter is prolonged.

According to the comparison test result with the common twist drill:

and (3) testing the punching life of 8KG of a common twist drill crane with the specification of 8 mm: 45 steel which is a processed material, the hardness of the material is 230HB, the punching depth is 15mm for through holes, the number of the holes to be punched is 406 finally, the hole expansion amount is between 0.1 and 0.2mm, the outlet has obvious burr problem, the hole wall has obvious scratch, and after 200 holes are processed, long scrap iron and winding cutter phenomenon occur. Under the condition of unchanged working condition, the product of the invention is used for punching, the last punching is 627 hole walls are visually smooth, the whole-process cutter cutting is stable, the hole expansion amount is between 0.05 and 0.07mm, and the scrap iron is small scraps. The burr and flash at the outlet of the hole are not obvious.

And (3) testing the punching efficiency of the 8KG hanging weight of the common twist drill with the specification of 8 mm:

processing 45 steel, material hardness 230HB, punching a through hole with depth of 15mm, linear speed Vc is 15m/min, feeding quantity F is 120mm/min, punching is 400, single-hole processing time is 7.5S+completely discharged for 2S and total 9.5S, cutting tools process 326, burning of the cutters, winding of scrap iron and stopping processing.

And (3) increasing the linear speed to Vc of 25m/min, punching 83 holes at the feed rate F of 150mm/min to generate abnormal sound, and stopping processing under the condition that scrap iron is not broken.

(2) When the product provided by the invention is used, the efficiency of punching 300 cutters is improved by 16% and finally the punching 300 cutters are free from obvious abnormality and defect under the conditions that the linear speed Vc is 25m/min and the feeding quantity F is 180mm/min, and the other cutters are unchanged, and the single-hole processing time is 5S+ and the total time is 8S.

While the foregoing is directed to the preferred embodiment of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. The technical scope of the present invention is not limited to the description, but must be determined according to the scope of claims.

Claims (10)

1. A double-spiral toothed strong chip breaking type flanging pagoda twist drill is characterized in that: including stalk portion and cutting part, the cutting part is including the pagoda cutting edge part and the margin cutting edge part that connect gradually, the front end of pagoda cutting edge part is equipped with at least one-level pagoda top, and the top of pagoda top is equipped with multistage pagoda ladder, every it is equipped with at least one main cutting edge tooth to prop up top of tower, every all be equipped with the minor cutting edge on each level of multistage pagoda ladder, every all be equipped with at least one minor cutting edge tooth on the minor cutting edge.

2. The double helical toothed strong chip breaking type flanging pagoda twist drill as set forth in claim 1, wherein: the number of the main cutting edge teeth on each main cutting edge is two, and the number of the auxiliary cutting edge teeth on each auxiliary cutting edge is one.

3. The double helical toothed strong chip breaking type flanging pagoda twist drill as set forth in claim 1, wherein: the depth h1 of the main cutting edge tooth is 0.02D, the width D1 of the main cutting edge tooth is 0.03D, and the main cutting edge tooth is provided with a concave arc-shaped groove with a relief angle of 8 degrees in the radial direction.

4. A twin helical toothed strong chip breaking type flanging pagoda twist drill as defined in claim 1 or 3, wherein: the rake face direction of the main cutting edge is provided with a positive rake angle correction face of 3-5 degrees, the radial correction depth h2 is 0.03D, and the axial correction length D2 is 0.05D.

5. The double helical toothed strong chip breaking type flanging pagoda twist drill as set forth in claim 1, wherein: the pagoda center is a compound multistage center structure and comprises a first center and a second center, wherein the second center is arranged at the front end of the first center, the vertex angle alpha 1 of the first center is 118 degrees+/-3 degrees, the vertex angle alpha 3 of the second center is 135 degrees+/-3 degrees, and a chip rolling groove is formed in the position of the vertex angle of the second center, which is matched with the position of the vertex angle penetrating through the two centers.

6. The double helical toothed strong chip breaking type flanging pagoda twist drill as set forth in claim 5, wherein: the radial direction of the second center is provided with two radially symmetrical circular arc symmetrical relief angle surfaces and two chisel edge lines, the circular arc relief angle alpha 4 of the circular arc symmetrical relief angle surfaces is 20 degrees, and the angle alpha 5 between the chisel edge line and the center line of the drill edge is 55 degrees.

7. The double helical toothed strong chip breaking type flanging pagoda twist drill as set forth in claim 1, wherein: the cutting edge part is provided with a spiral chip groove extending along the length of the chip groove, each stage of pagoda ladder and the spiral chip groove form a radial cutting edge part and an axial reinforcing connection part, the axial groove surface of the chip groove is connected with the circular arc rear cutting edge of the center to form a main cutting edge, the radial front cutting edge of the chip groove is connected with a blade back to form a secondary cutting edge, and two edges of the blade back along the spiral direction are respectively provided with a cutting edge used for guiding and supporting.

8. The double helical toothed strong chip breaking type flanging pagoda twist drill as set forth in claim 7, wherein: the helix angle alpha 2 of the spiral chip removal groove is 20 degrees to 30 degrees, and the chip removal groove is provided with a flanging.

9. The double helical toothed strong chip breaking type flanging pagoda twist drill as set forth in claim 7, wherein: the chip groove has a taper structure with small front and large rear, and the core thickness increment of the cutting edge part of the pagoda is as follows: the core thickness increment of the cutting edge part of the cutting edge margin is 0.03-0.08mm in every 100mm length: 1.5-2.0mm per 100mm length.

10. The double helical toothed strong chip breaking type flanging pagoda twist drill as set forth in claim 1, wherein: negative rake angle passivation treatment is carried out on all cutting edges of the cutting edge part, the uniformity of the negative rake angle passivation treatment is within 0.005mm, and the width is 0.02mm.