CN115121851A

CN115121851A - Discrete edge variable tooth pitch end mill

Info

Publication number: CN115121851A
Application number: CN202210405077.1A
Authority: CN
Inventors: 郑敏利; 秘玉琦; 聂婉莹; 刘月秀; 徐世成
Original assignee: Harbin University of Science and Technology
Current assignee: Harbin University of Science and Technology
Priority date: 2022-04-18
Filing date: 2022-04-18
Publication date: 2022-09-30

Abstract

The invention relates to a discrete edge variable tooth pitch end mill, which structurally comprises a handle part and an edge part. Be equipped with a plurality of chip grooves on the cutting part, form the structural style of discrete sword, this structure divides the bits easily, prevents that the piece from detaining. The dynamic balance is improved by changing the clearance angle on two adjacent spiral cutting edges so as to reduce eccentricity. In the cutting process, because the traditional cutter is easy to generate cutting vibration when cutting a workpiece, the structure of changing the tooth space angle and the spiral angle is selected, the probability of generating the flutter can be effectively reduced, and the surface processing quality is improved. The invention has the advantages of preventing chips from being retained, stably cutting, prolonging the service life of the cutter, high processing efficiency and the like.

Description

Discrete edge variable tooth pitch end mill

Technical Field

The invention relates to the field of machining cutter design, in particular to a discrete-edge variable-pitch end mill.

Background

Milling cutter is as present very common production machining tool, when using the end milling cutter processing work piece of spirals such as tradition, the cutter is with fixed frequency work to make the work piece produce the phenomenon of shimmying in the course of working, make the cutter produce great vibration, lead to the cutter to be ruined, the cutter is when cutting simultaneously, and the piece also can not in time be discharged, influences machining efficiency. In order to cope with this situation, a structure of varying helix or varying tooth pitch is adopted, but this causes different cutting loads to be applied to adjacent cutting edges and different peak values of cutting force to be applied to adjacent cutting edges, which is related to the selected sizes of the helix angle and the tooth pitch angle, so that the sizes thereof need to be reasonably selected. In order to improve the situation, the milling cutter provided by the invention is provided to play a positive role in promoting efficient cutting machining.

Disclosure of Invention

The invention aims to solve the problems, designs the discrete edge variable pitch end mill, indirectly changes the pitch and the waveform of cutting force by changing the helical angle and the tooth space angle, reduces the vibration of a cutter, prolongs the service life of the cutter, and solves the problem of chip discharge by arranging a chip separation groove on a helical cutting edge.

The technical scheme of the invention is as follows:

its structure of discrete sword displacement end mill includes the stalk portion, has spiral cutting edge, discrete sword and the cutting part of chip groove, and the key is: the difference value of the spiral angles of the adjacent spiral cutting edges of the edge part is 2 degrees, the tooth space angles between the cutter teeth are different, and a discrete edge and a chip dividing groove are arranged on the edge.

The discrete-edge variable-pitch end mill is a 4-tooth edge, the adjacent helical angles are 36 degrees and 38 degrees respectively, and the rake angle is 10 degrees.

The radial section groove-shaped curve of the discrete blade variable pitch end mill consists of three sections of tangent arcs, and the sizes of the tangent arcs are respectively 13mm, 1.6mm and 5.7 mm.

The relief angles of the adjacent spiral cutting edges of the discrete edge variable pitch end mill are different and are respectively 8 degrees and 15 degrees.

The discrete edge variable tooth pitch end mill has the external diameter of 20mm, the edge part length of 40mm, the handle part length of 60mm, different groove opening angles of 63 degrees and 72 degrees respectively, tooth space angles of 87 degrees and 93 degrees respectively, and the radius of a central groove of 1 mm.

The width and the depth of chip separation grooves of adjacent spiral cutting edges of the discrete edge variable pitch end mill tend to be reduced along the ascending direction of a milling cutter shaft, the chip separation grooves on the two edges are distributed in a staggered mode, and the chip separation grooves on the two edges are gradually reduced in an equal difference mode.

The invention has the advantages of high rotating speed, reduced cutting vibration, prolonged service life of the cutter, easy chip separation, chip retention prevention, improved surface processing quality, stable cutting, high processing efficiency and the like.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention

FIG. 2 is a schematic diagram of the arrangement and distribution of chip dividing grooves

FIG. 3 is a schematic view of a groove-shaped curve of the radial section of the discrete edge variable pitch end mill according to the present invention

Description of drawings reference numbers: a handle part 1, an edge part 2, a spiral cutting edge 3, a central groove 4, a spiral cutting edge 5 and a chip dividing groove 6

Detailed Description

The discrete-edge variable-pitch end mill shown in fig. 1 includes a shank 1 and a lip 2 including a helical cutting edge 3 and a helical cutting edge 5. Wherein discrete edges and chip separating grooves are distributed on the spiral cutting edge, and the central groove 4 is positioned at the center of the top of the milling cutter.

The flute depth H of the chip-separating groove on the helical cutting edge 3 of the discrete edge variable pitch end mill shown in FIG. 2 ₁ Is 1.4mm, H ₂ Is 1.1mm, the groove width W ₁ Is 2.0mm, W ₂ The diameter of the groove is 1.25mm, namely the size of the groove is decreased progressively along the ascending direction of the milling cutter shaft in an equal difference mode, the groove depth is 1.4mm, 1.3mm, 1.2mm and 1.1mm in sequence, the groove width is 1.4mm, 1.3mm, 1.2mm and 1.1mm in sequence, and the groove spacing is 5.0 mm.

The flute depth H of the chip-separating groove on the helical cutting edge 5 of the discrete edge variable pitch end mill shown in FIG. 2 ₃ Is 1.4mm, H ₄ Is 1.0mm, and has a groove width W ₃ Is 2.0mm, W ₄ The diameter of the groove is 1.0mm, namely the size of the groove is gradually decreased along the ascending direction of the milling cutter shaft in an equal difference mode, the groove depth is sequentially 1.4mm, 1.3mm, 1.2mm, 1.1mm and 1.0mm, the groove width is sequentially 2.0mm, 1.75mm, 1.5mm, 1.25mm and 1.0mm, and the groove interval is 5.0 mm.

As shown in FIG. 3, the groove-shaped curve of the tool bit of the discrete edge variable pitch end mill is composed of three arcs, and the radii of the three tangent arcs respectively correspond to the arcs R ₁ Is 13mm and is in a circular arc R ₂ Is 1.6mm and is in a circular arc R ₃ Is 5.7 mm. Milling cutter tooth space angle theta ₁ Is 93 DEG theta ₂ Is 87 DEG, wherein the front angle gamma of the cutter ₀ Is 10 degrees, the radius r of the central groove is 1mm, and the groove opening angle gamma ₁ Is 72 DEG, gamma ₂ Is 63 deg..

In the discrete edge variable pitch end mill shown in fig. 3, the relief angle of adjacent helical cutting edges is different, α ₁ ＝15°，α ₂ ＝8°。

The invention is suitable for milling aluminum alloy materials and the like by using the discrete-edge variable-pitch end mill, improves the abrasion between the rear cutter face of the milling cutter and the processing surface of a workpiece by changing the relief angle of two adjacent spiral cutting edges, and improves the surface processing quality and dynamic balance. The structure of the variable spiral variable pitch chip dividing groove reduces cutting vibration, prolongs the service life of the cutter, and enables cutting to be stable, and the chip dividing groove of the previous spiral cutting edge and the chip dividing groove of the next spiral cutting edge are not on the same straight line, so that staggered distribution is formed, chips are easily divided, chip retention is prevented, and the processing efficiency is improved.

Claims

1. The utility model provides a discrete sword becomes tooth pitch end mill which the structure includes the stalk portion, has the cutting part of spiral cutting edge and chip-splitting groove, its characterized in that: the helical angle and the relief angle of adjacent spiral cutting edges on the edge part have difference values respectively, the number of chip separation grooves on the adjacent spiral cutting edges is different, and the groove depth and the groove width of different chip separation grooves are also changed.

2. A discrete-edge variable-pitch end mill according to claim 1, wherein: the milling cutter is a 4-tooth cutting edge, the front angle is 10 degrees, the back angles of adjacent cutting edges are respectively 8 degrees and 15 degrees, and the spiral angle angles of adjacent spiral cutting edges are respectively 36 degrees and 38 degrees.

3. A discrete-edge variable-pitch end mill according to claim 1, wherein: the groove-shaped curve of the radial section of the end mill consists of three sections of tangent circular arcs, the sizes of the tangent circular arcs are respectively 13mm, 1.6mm and 5.7mm, and the radius of a central groove is 1 mm.

4. A discrete-edge variable-pitch end mill according to claim 1, wherein: when the chip separating grooves are distributed in the upward direction of the milling cutter shaft, the number of the chip separating grooves of adjacent spiral cutting edges is different, and the groove width and the groove depth of the chip separating grooves are reduced.

5. A discrete-edge variable-pitch end mill according to claim 1, wherein: the tooth space angles of adjacent cutter teeth are different, the tooth space angles at symmetrical positions are equal, and the angles are respectively 87 degrees and 93 degrees.