CN114131063A

CN114131063A - Indexable turning blade for machining small parts

Info

Publication number: CN114131063A
Application number: CN202111416008.2A
Authority: CN
Inventors: 庄艳江; 李东进; 陈建张; 黄冬云
Original assignee: Xiamen Golden Egret Special Alloy Co Ltd
Current assignee: Xiamen Golden Egret Special Alloy Co Ltd
Priority date: 2021-11-25
Filing date: 2021-11-25
Publication date: 2022-03-04

Abstract

The invention discloses an indexable turning insert for small part machining, which comprises an insert body; the projection of the outline of the blade body is in a polygonal shape; cutting parts with the same structure are arranged in each corner of the upper surface and the lower surface of the blade body; the cutting part comprises a cutting edge formed by the intersection of an upper surface, a lower surface and a side surface and a cutting surface extending from the cutting edge along the upper surface and the lower surface towards the middle direction; the cutting edge comprises a knife tip arc edge corresponding to the position of the corner tip and side edges connected with two sides of the knife tip arc edge, and the side edges on the two sides are symmetrically distributed along the angular bisector of the corresponding corner; the side edges at both sides extend to the opposite upper surface or lower surface at a preset inclination angle, and the distance between the side edges and the middle reference surface of the thickness of the blade body is reduced along with the increase of the distance between the side edges and the arc edge of the tool nose. The invention can realize stable low-resistance processing and high-surface-quality processing of small-diameter parts under the working conditions of small cutting depth and small feeding.

Description

Indexable turning blade for machining small parts

Technical Field

The invention relates to the technical field of cutters, in particular to an indexable turning insert for machining small parts.

Background

A tool is a tool used for cutting machining in machine manufacturing, and is also called a cutting tool. There are a wide variety of tools, including tools for machining various outer surfaces, tools for hole machining, tools for thread machining, tools for gear machining, tools for cutting, and so forth. The small-size part is called as a small part for short, is mainly applied to high-precision industries such as 3C, automobile, medical treatment and the like, has extremely high requirements on the size precision and the surface quality of the part, and is mainly automatically processed on a center-moving machine, so that the small-size part has the advantages of small cutting resistance, good chip breaking, smooth chip removal and light and fast cutting during processing, has higher difficulty in turning compared with the common part, and puts higher requirements on the performance of a blade.

At present, the turning processing blade for small parts mainly adopts a simple two-dimensional groove type design and a precise three-dimensional chip breaking groove type design. The two-dimensional groove type is designed to be grooved on a front tool face, so that chip removal is smooth and easy during cutting, the cutting is light and fast, the surface quality is high, the chip breaking requirement cannot be met, and the chip winding problem is easy to occur during machining, so that the service life of a tool and the quality of a machined surface are influenced, and meanwhile, during automatic machining, abnormal machining and part scrapping risks can be generated. The precise three-dimensional chip breaker design mainly ensures the requirements of micro cutting depth and chip feeding and breaking, simultaneously, the cutting edges are symmetrically distributed, the two-way processing requirement can be met, but under the working conditions of small cutting depth and small feeding, the good effect of breaking and chip removal is difficult to realize, meanwhile, the designed edge type is not sharp enough and is difficult to realize good breaking, so that the resistance is large during cutting, and the processing size precision and the processing surface quality are influenced.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide an indexable turning insert for small part machining, which can realize stable low-resistance machining and high-surface-quality machining of small-diameter parts under the working conditions of small cutting depth and small feeding through structural improvement.

The technical scheme adopted by the invention for solving the technical problems is as follows: an indexable turning insert for small part machining comprising an insert body; the projection of the outline of the blade body is in a polygonal shape; the blade body having an upper surface, a lower surface and a side surface connected between the upper and lower surfaces; the middle part of the blade body is provided with a screw locking hole penetrating through the upper surface and the lower surface; cutting parts with the same structure are arranged in each corner of the upper surface and the lower surface of the blade body; the cutting part comprises a cutting edge formed by the intersection of an upper surface and a lower surface with a side surface and a cutting surface extending from the cutting edge along the upper surface and the lower surface towards the middle direction; the cutting edge comprises a knife tip arc edge corresponding to the position of the corner tip and side edges connected with two sides of the knife tip arc edge, and the side edges on two sides are symmetrically distributed along the angular bisector of the corresponding corner; the side edges of the two sides extend to the opposite upper surface or lower surface at a preset inclination angle, and the distance between the side edges and the middle reference surface of the thickness of the blade body is reduced along with the increase of the distance between the side edges and the arc edge of the tool nose.

The preset inclination angle of the side edges on the two sides is beta, and the beta is more than or equal to 5 degrees and less than or equal to 7 degrees.

The cutting surface comprises a rake surface, a raised structure and a groove bottom surface; the raised structures are distributed on the groove bottom surface, the top surface of each raised structure is parallel to the groove bottom surface, and the groove bottom surface is parallel to the side edges.

The rake face is connected between the cutting edge and the bottom surface of the groove, and the rake face extends towards the middle along a direction perpendicular to the cutting edge and at an angle alpha, wherein alpha is greater than or equal to 10 degrees and less than or equal to 15 degrees.

The bump structure comprises a first bump; the first bulge is in an inverted V shape and is positioned on the angle bisector of the corresponding corner, one end of the first bulge is close to the tool nose arc blade, and the other end of the first bulge extends towards the middle part along the angle bisector of the corresponding corner.

The first bulges are symmetrically distributed along the angle bisector of the corresponding corner.

The bump structure further comprises a second bump; the second bulge is in a large semi-sphere shape and is positioned on the angle bisector of the corresponding corner; the outer side end of the second protrusion is connected with the other end of the first protrusion.

The second bulges are symmetrically distributed along the angle bisector of the corresponding corner part.

The bump structure also comprises two third bumps; the two third bulges are in a small semi-sphere shape and are symmetrically distributed on two sides of the angle bisector of the corresponding corner part; the two third bulges are respectively connected with the second bulges at two sides of the inner side end of the second bulge.

The distance between the top surface of the second protrusion and the middle reference surface of the thickness of the blade body is greater than the distance between the top surface of the first protrusion and the middle reference surface of the thickness of the blade body.

Compared with the prior art, the invention has the beneficial effects that:

the cutting parts with the same structure are arranged in the upper corner and the lower corner of the blade body; the cutting part comprises a cutting edge formed by the intersection of an upper surface and a lower surface with a side surface and a cutting surface extending from the cutting edge along the upper surface and the lower surface towards the middle direction; the cutting edge comprises a knife tip arc edge corresponding to the position of the corner tip and side edges connected with two sides of the knife tip arc edge, and the side edges on two sides are symmetrically distributed along the angular bisector of the corresponding corner; the side edges of the two sides extend to the opposite upper surface or lower surface at a preset inclination angle, and the distance between the side edges and the middle reference surface of the thickness of the blade body is reduced along with the increase of the distance between the side edges and the arc edge of the tool nose. The structure of the invention can realize stable low-resistance processing and high surface quality processing of small-diameter parts under the working conditions of small cutting depth and small feeding.

The invention is further explained in detail with the accompanying drawings and the embodiments; an indexable turning insert for small part machining of the present invention is not limited to the embodiments.

Drawings

FIG. 1 is a schematic perspective view of an embodiment of the present invention;

FIG. 2 is a top view of an embodiment of the present invention;

FIG. 3 is an enlarged schematic view of section A of FIG. 2;

FIG. 4 is a schematic view of FIG. 2 taken along line B;

FIG. 5 is a sectional view taken along line C-C of FIG. 2;

fig. 6 is an enlarged schematic view (rotated by 90 degrees) of the portion D in fig. 5.

In the figure: 1. a blade body; 2. a screw lock hole; 3. cutting the surface; 31. a raised structure; 311. a first protrusion; 312. a second protrusion; 313. a third protrusion; 32. a rake face; 33. the bottom surface of the groove; 4. an upper surface; 5. a flank face; 6. a lower surface; 7. a cutting edge; 71. a knife tip arc edge; 72. a side edge; 73. a side edge; 8. a cutting part.

Detailed Description

Examples

Referring to fig. 1 to 6, an indexable turning insert for small part machining of the present invention includes an insert body 1; the projection of the outline of the blade body 1 is in a polygonal shape; the projection of the outline of the blade body 1 of the embodiment is in a regular triangle shape; the insert body 1 has an upper surface 4, a lower surface 6 and a side surface 5 connected between the upper and lower surfaces; the middle part of the blade body 1 is provided with a screw locking hole 2 penetrating through the upper surface and the lower surface; the upper surface 4 and the lower surface 6 are parallel symmetrical planes, and the positions of the upper surface 4 and the lower surface 6, which are close to the screw locking hole 2, are set as blade supporting surfaces; cutting parts 8 with the same structure are arranged in six corners of the upper surface and the lower surface of the blade body; the cutting part 8 comprises a cutting edge 7 formed by intersecting an upper surface, a lower surface and a side surface, and a cutting surface 3 extending from the cutting edge 7 to the middle direction along the upper surface and the lower surface, wherein the side surface 5 is a rear cutter surface, so that the cutting edge 7 is a sharp edge; the cutting edge 7 comprises a knife tip circular arc edge 71 corresponding to the position of the corner tip and

side edges

72 and 73 connected with two sides of the knife tip circular arc edge, and the

side edges

72 and 73 on the two sides are symmetrically distributed along the angular bisector of the corresponding corner; the

side edges

72, 73 of both sides extend to the opposite upper or lower surfaces at a preset inclination angle, and the distance between the

side edges

72, 73 and the middle reference plane of the thickness of the insert body 1 decreases as the distance from the nose arc edge 71 increases. In this embodiment, the upper surface 4 forms a 90 ° angle with the flank surface 5, ensuring sufficient strength of the insert. However, the invention can also be applied to a product with an acute included angle formed by the upper surface and the rear cutter surface, so that the rear cutter surface is prevented from interfering with a workpiece during cutting; the upper surface 4, the lower surface 6 and the rear cutter face 5 are directly connected to form a whole, so that the integral rigidity and strength of the blade are improved, and the fracture risk under severe working conditions is reduced.

As shown in fig. 2 to 4, the cutting edge 7 is composed of three segments: the cutting tool comprises

side edges

72 and 73 of two line segments at the left and right boundaries of the cutting surface 3 and a tool nose circular arc edge 71 connecting the two line segments, wherein the

side edges

72 and 73 are symmetrically distributed along the central line of the tool nose circular arc edge 71 and have the same characteristics; the

side edges

72 and 73 extend to the opposite surface at an inclination angle beta, the height of the middle reference surface relative to the thickness of the blade body 1 is reduced along with the increase of the distance from the knife tip arc edge 71, wherein beta is more than or equal to 5 degrees and less than or equal to 7 degrees, the knife tip arc edge 71 is at a high point during cutting, and the

side edges

72 and 73 are at a low point during cutting, so that the cutting is lighter and faster, meanwhile, in the embodiment, the length of the

side edges

72 and 73 is more than 3.5mm, thereby ensuring enough cutting depth and improving the processing universality.

As shown in fig. 2, the cutting surface 3 consists of three parts: the cutting tool comprises a front tool face 32, a convex structure 31 and a groove bottom face 33, wherein the front tool face 33 is a face connecting a cutting surface 3 and a cutting edge 7, and an included angle alpha is formed between the face and a horizontal plane parallel to the upper surface and the lower surface, namely the front tool face 32 extends along a direction perpendicular to the cutting edge 7 and at an angle alpha, wherein the angle alpha cannot be too small, the cutting edge cannot be too blunt if the angle alpha is too small, the cutting resistance is large, the quality of the processed surface is influenced, meanwhile, the angle alpha cannot be too large, the cutting is too sharp if the angle alpha is too large, the strength is insufficient, the cutting is easy to break, and the cutting life of the cutting tool is influenced, the angle alpha is more than or equal to 10 degrees and less than or equal to 15 degrees, the sufficient sharpness of the cutting blade is ensured, and meanwhile, certain strength is achieved; it should be noted here that the angle α in the same cutting portion 8 is constantly changing, the position α closer to the arc edge is larger, and the position α farther from the nose arc edge 71 is smaller, but no matter how the angle is changed, the angle is within the range of α being not less than 10 ° and not more than 15 °, such design is for making the cutting edge participating in cutting sharper when the cutting depth is small, which is beneficial to improving the quality of the machined surface and chip breaking, and when the cutting depth is large, the cutting edge participating in cutting has certain strength, which is beneficial to avoiding the risk of edge breaking; in conclusion, under the action of the structure, the cutting tool can show excellent cutting service life and processing surface quality under wide working conditions.

Referring to fig. 3 and 6, the protruding structures 31 are distributed on the groove bottom surface 33, the top surfaces of the protruding structures 31 are parallel to the groove bottom surface 33, the groove bottom surface 33 is parallel to the

side edges

72 and 73, the distance between the cutting edge and the groove bottom is fixed, the height difference between the cutting edge 7 and the protruding structures 31 is relatively fixed, chips with different cutting depths can be curled through the groove bottom and the protrusion, and good chip breaking is achieved.

Referring to fig. 3, the bump structure 31 includes a first bump 311; the first protrusion 311 is in an inverted V shape, and the first protrusion 311 is located on the bisector of the corresponding corner, one end of the first protrusion 311 is close to the knife tip arc edge 71, and the other end extends toward the middle along the bisector of the corresponding corner. The first protrusions 311 are symmetrically distributed along the bisector of the corresponding corner.

The bump structure 31 further includes a second bump 312; the second protrusion 312 is in a big semi-sphere shape, and the second protrusion 312 is located on the angle bisector of the corresponding corner; the outer end of the second protrusion 312 is connected to the other end of the first protrusion 311. The second protrusions 312 are symmetrically distributed along the bisector of the corresponding corner.

The protrusion structure 31 further includes two third protrusions 313; the two third protrusions 313 are in a small semi-sphere shape and are symmetrically distributed on two sides of the angle bisector of the corresponding corner; the two third protrusions 313 are connected to the second protrusion 312 at two sides of the inner end of the second protrusion 312, respectively.

The first bulge 311 is in an inverted V shape, so that chips can be properly and effectively processed within a certain cutting depth range no matter the cutting depth is small or large, or the cutting depth is changed, and the chips can be stably curled, broken and smoothly discharged; the second bulge 312 is in a large semi-sphere shape, so that the chips can be smoothly discharged along the arc surface when the cutting depth is large, and meanwhile, the friction heat generated by the contact of the chips and the bulge can be effectively reduced, so that the generated temperature is reduced; the third protrusion 313 is in the shape of two separated small hemispheres, is symmetrically distributed on the groove bottom surface 33 by taking the central line of the arc edge as a bisector and is connected with the upper surface 4.

Referring to fig. 6, the first protrusion 311 and the second protrusion 312 have a height difference, and based on the groove bottom surface 33, the first protrusion 311 is lower, and the second protrusion 312 is higher, that is, the distance between the top surface of the second protrusion 312 and the middle reference surface of the thickness of the insert body is greater than the distance between the top surface of the first protrusion 311 and the middle reference surface of the thickness of the insert body. Thus, the chip breaking effect can be well guaranteed under different cutting depth conditions, and meanwhile, in order to guarantee good positioning support, the height of the upper surface 4 is higher than that of the cutting edge, the front cutter surface and the protruding portion.

Referring to fig. 6, the top surface of the first protrusion 311 is connected to the groove bottom surface 33 by a slope, which ensures smooth chip discharge.

Referring to fig. 3, the distance between the inverted V-shaped first protrusion 311 and the nose arc edge 71 is not too close, which mainly ensures a sufficient chip containing space, so that the chip can be discharged more smoothly, and the cutting resistance is lower.

The invention can lead the blade to have higher sharpness, simultaneously realize good chip treatment under the conditions of small cutting depth and small feeding, and lead the cutting processing to be lighter and faster and the quality of the processed surface to be better.

The foregoing is considered as illustrative of the preferred embodiments of the invention and is not to be construed as limiting the invention in any way. Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make many possible variations and modifications to the disclosed embodiments, or equivalent modifications, without departing from the scope of the disclosed embodiments. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention should fall within the protection scope of the technical scheme of the present invention, unless the technical spirit of the present invention departs from the content of the technical scheme of the present invention.

Claims

1. An indexable turning insert for small part machining comprising an insert body; the projection of the outline of the blade body is in a polygonal shape; the blade body having an upper surface, a lower surface and a side surface connected between the upper and lower surfaces; the middle part of the blade body is provided with a screw locking hole penetrating through the upper surface and the lower surface; the method is characterized in that: cutting parts with the same structure are arranged in each corner of the upper surface and the lower surface of the blade body; the cutting part comprises a cutting edge formed by the intersection of an upper surface and a lower surface with a side surface and a cutting surface extending from the cutting edge along the upper surface and the lower surface towards the middle direction; the cutting edge comprises a knife tip arc edge corresponding to the position of the corner tip and side edges connected with two sides of the knife tip arc edge, and the side edges on two sides are symmetrically distributed along the angular bisector of the corresponding corner; the side edges of the two sides extend to the opposite upper surface or lower surface at a preset inclination angle, and the distance between the side edges and the middle reference surface of the thickness of the blade body is reduced along with the increase of the distance between the side edges and the arc edge of the tool nose.

2. The indexable turning insert for small part machining according to claim 1 wherein: the preset inclination angle of the side edges on the two sides is beta, and the beta is more than or equal to 5 degrees and less than or equal to 7 degrees.

3. The indexable turning insert for small part machining according to claim 1 wherein: the cutting surface comprises a rake surface, a raised structure and a groove bottom surface; the raised structures are distributed on the groove bottom surface, the top surface of each raised structure is parallel to the groove bottom surface, and the groove bottom surface is parallel to the side edges.

4. The indexable turning insert for small part machining of claim 3 wherein: the rake face is connected between the cutting edge and the bottom surface of the groove, and the rake face extends towards the middle along a direction perpendicular to the cutting edge and at an angle alpha, wherein alpha is greater than or equal to 10 degrees and less than or equal to 15 degrees.

5. The indexable turning insert for small part machining of claim 3 wherein: the bump structure comprises a first bump; the first bulge is in an inverted V shape and is positioned on the angle bisector of the corresponding corner, one end of the first bulge is close to the tool nose arc blade, and the other end of the first bulge extends towards the middle part along the angle bisector of the corresponding corner.

6. The indexable turning insert for small part machining according to claim 5, wherein: the first bulges are symmetrically distributed along the angle bisector of the corresponding corner.

7. The indexable turning insert for small part machining according to claim 5, wherein: the bump structure further comprises a second bump; the second bulge is in a large semi-sphere shape and is positioned on the angle bisector of the corresponding corner; the outer side end of the second protrusion is connected with the other end of the first protrusion.

8. The indexable turning insert for small part machining according to claim 7, wherein: the second bulges are symmetrically distributed along the angle bisector of the corresponding corner part.

9. The indexable turning insert for small part machining according to claim 5, wherein: the bump structure also comprises two third bumps; the two third bulges are in a small semi-sphere shape and are symmetrically distributed on two sides of the angle bisector of the corresponding corner part; the two third bulges are respectively connected with the second bulges at two sides of the inner side end of the second bulge.

10. The indexable turning insert for small part machining according to claim 7, wherein: the distance between the top surface of the second protrusion and the middle reference surface of the thickness of the blade body is greater than the distance between the top surface of the first protrusion and the middle reference surface of the thickness of the blade body.