CZ2013123A3 - Shank-type angle cutter with edges in helix - Google Patents

Abstract

The helical shank cutter is equipped with a new Integrated IMG microgeometry, which is located on the front of the tooth (8). The integrating function of the surface (1) is achieved by spatially collapsing the surface. The outer edges of the surface (1) of the IMG form cutting edges (3, 4, 5). The decisive factor is the continuous modification of the cutting edge (5), which reinforces the entire corner area of the tooth without creating unwanted edges on the forehead.

Description

End mill with helical blades.

Technical field

The invention relates to a helix cutter, in particular its so-called microgeometry, in particular the part of the helix where the cutting edges intersect the front face of the cutter, i.e. the corner part of the cutter.

BACKGROUND OF THE INVENTION

For all end mills with metal cutting edges, otherwise with grooves, in a helix from helix size greater than 15 ° - most commonly 20 °; 25 °; 30 °; 45 °; 50 ° and more, including all intermediate dimensions, must be made in the slot at the cutter corner to reduce this angle to an acceptable size within the range of ⁸ to 20 ° or more, taking into account the cutting resistance of the workpiece.

The height of this "blunt" is around 5% of the nominal diameter D of the milling cutter. The actual operation is performed for end mills by grinding the face of the milling cutter at this smaller angle of approximately 0 °; 5 °; 10 °; 15 °.

Without this adjustment, the cutting edges on the forehead would be too unstable due to the direction of the resultant cutting forces with a considerable bending moment acting on the corner portion of the cutting edge. The combination of the cutting angle and the angle of the original helix faces this bending moment by directing the resultant to a plane with a larger and more stable cross-section, but at the same time creates a breaking edge on the peripheral cutting edge. then determines the life of the cutter. In addition to the mentioned impact of extreme wear on the service life, the corner area is still a limit for increasing the amount of feed per tooth, far from being possible in the cylindrical portion of the entire helix cutting length.

2. Summary of the Invention

The above drawbacks are largely overcome by the helix burrs of the present invention. It is based on the fact that a new face is created on the tooth face, starting at the end of the cutter and ending at a distance of 5 to 10% of the nominal diameter D of the cutter, the main cutting edge in its corner area formed by a smooth smooth transition the modified helix angle at the beginning of the cutting edge and the nominal helix angle of the cutter.

The invention further describes cutting microgeometry of the cutting edge in the critical corner region of the end mills, which is introduced by the new Integrated MicroGeometry (hereinafter IMG) of the tooth face in the corner region. It is in the shape of a spatially warped continuous smooth surface on the tooth face. At the same time, the IMG surface creates a new shape of the cutter's main cutting edge at its corner, which forms a smooth, smooth transition of the helix at the beginning of the cutting edge, which is usually 0 to 25 °, and a nominal helix angle of 20 to 60 °. This eliminates the fracture transition between the cut and the helix and the resulting initiation of the extreme value of the abrasion value Vb on the back of the teeth and extends the life of the milling cutter.

The benefit of the IMG surface according to the invention can be used in the whole range of end milling cutters with helical flutes greater than 15 °. Especially for grooving cutters and milling cutters.

Clarified? of the drawings

DETAILED DESCRIPTION OF THE INVENTION The invention will be explained in more detail with reference to the accompanying drawings, in which: FIG. 1 is a general view of a shank, end milling cutter. Figures 2 and 3 show a detail of the corner region when comparing standard and new microgeometry. FIG. 4 shows a detail of the cutting edge.

Examples Realized? invention

As an exemplary application of the invention, a shank with helical flutes is mentioned regardless

-3 ·. The number of cutting edges shown in FIG. 1. This type of end milling cutters with an IMG surface according to the invention exhibits increased tool life and performance. The IMG surface can be ground during initial production or after regrinding of standard milling cutters.

Two important features of the invention are seen in the models of a particular embodiment of the invention, i.e. shaping the cutting edge curve and modifying the cutting angle. Fig. 4 shows a continuous helix size transition in the corner region from the nominal 45 ° to 15 ° without creating a sharp dividing edge as a source of extreme wear

The new microgeometry end mill is provided with a surface 1 which is located on the face 9 of the tooth 8. The outer edges of the surface 1 are formed by blades 3, 4, 5, which have a different shape from the standard. What is decisive is the change in the inclination of the cutting edge 3, and in particular the continuous modification of the main cutting edge 5, which decisively strengthens the entire corner area of the tooth 8 without forming undesirable edges and which adjoins the edge 6 of the back. This achieves an exit angle of 15 ° instead of an unacceptable 45 °. The extreme surface of the abrasive pad vb is thereby suppressed on the ridge surface 7 during milling.

Industrial applicability

The IMG-surface helix bit mill according to the present invention finds particular application in sharp-corner and straight-chamfered cutters at any chamfer angle. It will meet the increased demands in machining high-impact and rigid materials, and will also allow increased feed per tooth for conventional machined materials. Its use can be a matter of course equipment of end mills, bearing the mark of the future standard. It is particularly suitable for the current trend in performance machining, known in the public by the abbreviation HPC (High Performance Cutting)

Claims (1)

Helical end mill with helical blades, characterized in that on the end face (9) of the tooth (8), in its corner region, it has a front face (1) having its origin at the end of the cutter, with a continuously decreasing at an angle of the main cutting edge (5) from the original helix angle up to 15 to 20 ° at a distance of 5 to 10% of the nominal diameter D of the milling cutter from its face (2).