DE202017103022U1 - End mills - Google Patents

Abstract

End mill (1) with a core (11) to which connect peripherally at least two peripheral cutting, wherein a chip depth is defined by one peripheral edge, characterized in that at least one peripheral cutting edge forms a reference cutting edge (R) and the chip space depth of at least a reference cutting edge (R) from an end face (1S) of the end mill (1) towards at least one clamping region (1E) of the end mill (1) is reduced and the chip space depth of at least one further peripheral cutting edge of a first circumferential cutting edge (U1) from the direction the end face (1S) of the end mill (1) in the direction of the clamping region (1E) of the end mill (1) at least partially increased.

Description

The invention relates to an end mill according to the preamble of the first patent claim. The end mill is to be used preferably for high-performance machining of particular workpieces of metallic material, ceramic material, plastics, composite materials (such as fiber composite material), etc. application.

Known end mills usually consist of a base material of high-speed steel (high-speed steel - derived HSS), hard metal, cermet (composed of English ceramic and metal = composites of ceramic materials in a metallic matrix (binder)), ceramics and other mostly high-strength materials or material combinations. Conventional end mills have cutting in the form of peripheral cutting and cutting edges. The cutting edges can have unequal tooth pitches in relation to one another and different spiral angles in the radial section. The Spanraumtiefen the cutting edges to each other and in the course of the individual cutting from the end to the shaft are uniform and the core of the end mill has a uniform cylindrical shape. Behind the clearance angle of the peripheral cutting edge of the end mill has a puncture. Due to the unequal tooth pitches and the different spiral angles of the main cutting edges, different tooth widths are created. In order to achieve a uniform width of the clearance angle, a puncture is ground at a defined distance from the cutting edge. This has the disadvantage that the power transmission to the cutting edge is not optimal and the stability of the cutting edge is greatly reduced or the end mill wears faster. The end mill has the same rake angle over the entire chip space length at each cutting edge.

From the publication DE 10 2015 214 964 A1 For example, there is known an asymmetrical endmill whose cutting portion has a plurality of unequally indexed blades separated by flutes, at least one of the flutes being of unequal length and the cutter having an imbalance. This can be disadvantageous especially at very high speeds.

From the publication DE 200 23 770 U1 discloses a mill or a rotatable multi-toothed end mill, in which the total cross-sectional area of the milling material gradually increases from the cutting end in the direction of the clamping area. The cross-sectional area increases continuously uniformly circumferentially, whereby each chip space has the same geometry. As a result, strong vibrations may occur during machining.

In the publication DE 102 43 403 A1 a method for producing a tool, in particular a drill or milling cutter is described. The cutter or drill has at least one conveyor spiral, wherein this is introduced in a single operation. The chip space depth is formed constant or variable formed over the length of the drill. According to the document, the mill / drill has only one cutting edge, which brings out the material from a bore on the conveyor spiral.

A milling tool is in the publication AT 14275 U1 named. The milling tool has a head portion with a plurality of spirally rotating blades and a clamping portion for receiving at a machining center. The blades define the direction of rotation of the milling tool in the machining center and have flutes between the blades, with a first spirally rotating blade and a second spiral blade following the first blade in a second flute arranged such that at each axial position of the blade Head portion of the spiral angle of the second cutting edge is smaller than the spiral angle of the first cutting edge, and the core radius of the second flute decreases from the free end in the direction of the tool holder. The chip spaces at the free end are formed uniformly by the geometry, with the first flute not changing its depth in the direction of the clamping area. Only the second flute becomes deeper in the direction of the clamping area and therefore changes the geometry. This can lead to an imbalance in the cutter, which leads to vibrations and vibrations at very high speeds.

From the publication JP 2007-136627 A a milling cutter is known in which the individual chip spaces have different depths. These remain evenly in the geometry from the free end in the direction of the clamping section. Again, vibrations may occur during processing.

The invention is based on the object to develop an end mill, with which the Zeitspanvolumen increases and the life / the end of life can be significantly increased and which has a favorable wear behavior.

The object of the invention is achieved by the characterizing features of the first protection claim.

Advantageous embodiments emerge from the subclaims.

The end mill has a core to which at least two circumferential cutting edges adjoin, wherein a chip space is defined by one peripheral cutting edge and wherein according to the invention at least one peripheral cutting edge forms a reference cutting edge and wherein the chip space depth of the at least one reference cutting edge extends from an end face of the end mill in the direction is at least partially reduced to a clamping region of the end mill and wherein the chip space depth of at least one further peripheral edge of a first Umfangsschneidenart at least partially increases from an end face of the end mill towards a clamping region of the end mill.

In this case, the chip space depth of the reference cutting edge over the entire length or a length range is reduced, and the chip space depth of the further peripheral cutting edge of the first peripheral cutting type increases over the entire length or a length range which preferably corresponds to the length range of the reference cutting edge.

Advantageously, the chip space depth of the at least one further peripheral cutting edge of the first peripheral cutting edge type increases from the end face of the end mill towards a clamping region of the end mill opposite to the course of the chip space depth of the reference cutting edge.

Due to the mutually changing chip space depths of the reference cutting edge and the peripheral cutting edge of the first peripheral cutting edge type, the occurring oscillations are surprisingly considerably reduced during milling.

In a further preferred embodiment, the chip space depth of the at least one reference cutting edge from the end face of the end mill towards the clamping area of the end mill is constant over a first length range and decreases over a second length range. In this case, the chip space depth of the further peripheral cutting edge of the first peripheral cutting edge type is also constant from the end face of the end mill towards the clamping region of the end mill over a first length range and increases over a second length range

According to a further variant of the invention, the chip space depth of the at least one reference cutting edge decreases from the end face of the end mill towards the clamping region of the end mill over a first length range and extends over a second length range, the chip space depth of the further peripheral cutting edge of the first peripheral cutting edge type from the end face of the end mill increases in the direction of the clamping region of the end mill over a first length range and extending over a second length range remains constant.

The chip space depth of the further peripheral cutting edge of the first peripheral cutting edge on the front side or in the direction of the end side preferably corresponds essentially to the chip space depth of the reference cutting edge in the direction of the clamping region, and the chip space depth of the further peripheral cutting edge of the first circumferential cutting edge in the direction of the clamping region corresponds essentially to the chip space depth Reference cutting edge on the front side.

However, it is also possible to make the chip space depth of the peripheral cutting edge of the first peripheral cutting type smaller in the direction of the clamping region than the chip space depth of the reference cutting edge on the stimulus region in order to form a core which is somewhat more stable in the direction of the clamping region.

The reduction of the chip space depth of the at least one reference cutting edge and / or the increase of the chip space depth of the at least one further peripheral cutting edge of the first peripheral cutting edge type from the end face of the end mill towards the clamping region of the end mill preferably takes place linearly.

The end mill according to the invention, in addition to at least one reference cutting edge and at least one further first peripheral cutting edge, additionally comprise at least one further second cutting edge type, the chip space depth of the peripheral cutting edge of the further second cutting edge type remaining constant or substantially constant from the end face of the end mill toward the clamping region of the end mill runs.

The core has a shape deviating from the circular shape, which extends from the end face in the direction of the clamping area spirally.

The core also changes its shape in the course from the front to the clamping area.

A further advantageous design of the end mill is that the rake angles of at least two circumferential sheaths are different from one another and / or that the rake angle of at least one circumferential cutting edge changes from the end region to the clamping region.

Particularly preferably, circumferentially close to the core exactly four or exactly five peripheral cutting on.

Of course, the cutter can also have 3 to 6 or more than 6 peripheral cutting.

• ○ eine Umfangsschneide die Referenzschneide ist oder
• ○ zwei Umfangsschneiden die Referenzschneiden sind.

The Schaffräser can have exactly three peripheral cutting, wherein

• ○ a peripheral cutting edge is the reference cutting edge or
• ○ two circumferential cutting edges are the reference cutting edges.

At least one further peripheral cutting edge is a peripheral cutting edge of the first peripheral cutting edge type. In an embodiment with a reference cutting edge and a further peripheral cutting edge of the first peripheral cutting edge type, the second further peripheral cutting edge can be both a peripheral cutting edge of the first and the second peripheral cutting edge type.

Or the end mill has exactly four peripheral cutting, wherein two opposing peripheral cutting edges are the reference cutting edges and between each two reference cutting edges each have a further peripheral cutting edge is arranged. At least one further peripheral cutting edge is a peripheral cutting edge of the first peripheral cutting edge type. The second further peripheral cutting edge can be both a peripheral cutting edge of the first and the second peripheral cutting edge type.

It is also possible that two adjacent peripheral cutters are the reference cutters.

• o eine Umfangsschneide die Referenzschneide ist wobei wenigstens eine der weiteren vier Umfangsschneiden eine weitere Umfangsschneide der ersten Umfangsschneidenart ist oder
• o zwei Umfangsschneiden die Referenzschneiden sind und jeweils zwischen den zwei Referenzschneiden einmal eine weitere Umfangsschneide und einmal zwei nebeneinander liegende weitere Umfangsschneiden angeordnet sind oder
• o drei Umfangsschneiden die Referenzschneiden sind und jeweils zwei Referenzschneiden zueinander benachbart sind und zwischen den zwei benachbarten und der dritten Referenzschneide jeweils eine weitere Umfangsschneide angeordnet ist

The end mill can also have exactly five peripheral cutting, wherein

• a circumferential cutting edge is the reference cutting edge, wherein at least one of the further four circumferential cutting edges is a further peripheral cutting edge of the first circumferential cutting edge type or
• o two peripheral cutting edges are the reference cutting edges and in each case between the two reference cutting edges a further peripheral cutting edge and once two adjacent further peripheral cutting edges are arranged, or
• o three peripheral cutting edges are the reference cutting edges and in each case two reference cutting edges are adjacent to each other and between the two adjacent and the third reference cutting edge in each case a further peripheral cutting edge is arranged

Even in an embodiment with exactly five peripheral cutting edges, at least one further peripheral cutting edge is a circumferential cutting edge of the first circumferential cutting edge type. The remaining peripheral cutting edges may be of the first and / or the second peripheral cutting edge type.

• o wenigstens eine Umfangsschneide eine Referenzschneide ist und wobei wenigstens eine der weiteren fünf Umfangsschneiden eine weitere Umfangsschneide der ersten Umfangsschneidenart ist oder
• o wenigstens zwei Umfangsschneiden die Referenzschneiden sind und zwischen den Referenzschneiden weitere Umfangsschneiden angeordnet sind wobei wenigstens eine weitere Umfangsschneide eine Umfangsschneide der ersten Umfangsschneidenart ist oder
• o drei Umfangsschneiden die Referenzschneiden sind, wobei jeweils zwischen zwei Referenzschneiden eine weitere Umfangsschneide angeordnet ist und wobei wenigstens eine der weiteren Umfangsschneiden eine Umfangsschneide der ersten Umfangsschneidenart ist.

It is also possible that the end mill has exactly six peripheral cutting edges, wherein

• o at least one peripheral cutting edge is a reference cutting edge and wherein at least one of the further five peripheral cutting edges is a further peripheral cutting edge of the first peripheral cutting edge type or
• o at least two peripheral cutting edges are the reference cutting edges and further peripheral cutting edges are arranged between the reference cutting edges, wherein at least one further peripheral cutting edge is a circumferential cutting edge of the first circumferential cutting edge type or
• o three peripheral cutting edges are the reference cutting edges, wherein in each case between two reference cutting edges a further peripheral cutting edge is arranged and wherein at least one of the further peripheral cutting edges is a peripheral cutting edge of the first circumferential cutting edge type.

Even in an embodiment with exactly six peripheral cutting edges, at least one further peripheral cutting edge is a peripheral cutting edge of the first peripheral cutting edge type. The remaining peripheral cutting edges may be of the first and / or the second peripheral cutting edge type. In the embodiment with two opposite reference cutting edges, the peripheral cutting edges of the first and / or the second circumferential cutting edge type are preferably arranged in pairs opposite each other.

It is possible that several or all peripheral cutting edges extend from the end face in the direction of the clamping area in mutually different spiral angles.

The spiral angles of adjacent circumferential cutting edges can become larger or smaller in the circumferential direction and / or the spiral angle of at least one circumferential cutting edge can vary from the end face to the clamping region.

Surprisingly, it was found and demonstrated by experiments that the service life or the tool life of the end mill according to the invention could be increased by more than twice compared to conventional end mills by this novel structural design. This means that also the time wastage volume could be increased considerably.

Preferably, the chip space depth of several or all peripheral cutting edges is changed from the end face of the milling cutter in the direction of the clamping area of the milling cutter. When peripheral cutting the second Umfangsschneidenart are in particular conventional peripheral cutting.

The peripheral cutting can be made in any length and the peripheral cutting edges also have different lengths.

Advantageously, at least one end cutting edge extends up to the radial center of the end mill in order to ensure machining over the entire end face region and the removal of the chips.

According to a variant of the invention, some or all of the peripheral cutting edges may have an unequal tooth pitch relative to each other in the radial section.

Furthermore, it is possible that at least two or all peripheral cutting edges have mutually different spiral angles.

It is also possible for the peripheral blades to have a variable spiral angle varying over their length such that the spiral of a blade on the face of the cutter begins with a defined first helix angle which varies towards the chucking region, i. increased or decreased to a second spiral angle.

According to a further variant, the chip space size and / or a chip space profile between two adjacent peripheral cutting edges is different from a chip space size and / or a chip space profile between at least one further peripheral cutting edge or chip space size and / or the chip space profile of two other adjacent peripheral cutting edges.

Due to the different chip space depths or chip space profiles and thus the different chip space sizes, the core of the end mill has at least a section of a circular shape in cross-section and may for example have an elliptical or otherwise non-circular core shape.

The core shape thereby changes spirally in the course from the forehead to the clamping area.

The radially outer cutting edges of the peripheral cutting edges lie on a common outer diameter. The diameter of the cutting edges may vary over the length of the cutting area (e.g., in the form of a circumferential diameter taper from the face towards the clamping area). with conical cutters. Also, the cutter can be made flat or in the form of a radius on its front side.

It can also cutting edge differences are provided under the edges to each other, so that the outer contour varies over the length and the outer contour can also be elliptical or oval. The core may extend helically into the clamping area.

Overall, the core thus changes in its cross-sectional shape as a function of the axial position.

Furthermore, the core may vary in its cross-section over the length of the circumferential sheaths or a static shape (consistent over the entire length of the peripheral cutting edges) or a variable shape (changing according to the shape and shape of the circumferential sheath and the resulting Spanraumtiefen) exhibit.

In this case, the rake angle of at least two peripheral cutting edges or even several or all peripheral cutting edges may be different from one another. The rake angle (s) of the peripheral cutters can also change from the front end of the end mill to the clamping area, for example, becoming larger or smaller in the direction of the clamping area.

The shape of the core is thus significantly defined by the Spanraumtiefen the peripheral cutting and / or the chip space profiles.

The chip space sizes and the chip space course and / or the tooth back contours of at least two circumferential cutting edges are preferably different from one another and / or have a variable size over the length of the peripheral cutting edges.

The chip space depth of at least two circumferential sheaths is designed differently.

Between two adjacent peripheral cutting edges, an offset angle is provided on the circumference, wherein at least one peripheral cutting edge has a chip space depth which differs from the chip space depths of the other peripheral cutting edges.

If an end mill, for example, has four peripheral cutting edges, a first peripheral cutting edge has a first chip space depth, one offset circumferentially at a first offset angle arranged second peripheral edge a second chip space depth, a second offset angle circumferentially offset to the second peripheral edge arranged third peripheral edge a third chip space depth and a third offset angle circumferentially offset to the third peripheral edge arranged fourth peripheral edge has a fourth chip space depth, wherein between the fourth peripheral edge and the first circumferential cutting a fourth offset angle is present.

The chip space depths of the substantially opposite peripheral cutting edges are preferably of the same design, that is, with four peripheral cutting edges, the chip clearance depths of the first and third peripheral cutting edges and / or the chip clearance depths of the second and fourth peripheral cutting edges are each made equal in pairs.

The chip space depth of the first and third peripheral cutting edges is the largest in the end section of the end mill (these then form the reference cutting edges) and decreases in the direction of the clamping region to a smallest chip space depth.

The chip space depths of the further second and third peripheral cutting edges are smallest in the end section of the end milling cutter and increase in the direction of the clamping region (peripheral cutting of the first type). In this case, the largest chip space depth of the first and third peripheral cutting edges (reference cutting edges) preferably corresponds essentially to the largest chip space depth of the further second and fourth peripheral cutting edges (1st type) at the end of the peripheral cutting edges in the direction of the clamping region and the smallest chip space depth of the further second and fourth peripheral cutting edges (FIG. 1st type) in the stimulus of the smallest chip space depth of the first and third peripheral cutting edge (reference cutting edge) at the end towards the clamping area.

In this case, therefore, the first and the third peripheral cutting edge (reference cutting edge) and / or the further second and fourth peripheral cutting edge (first type) are formed substantially equal but opposite to each other.

Preferably, to the same extent as the chip space depth of the first and third circumferential sheath (reference cutting edge) decreases from the end region in the direction of the clamping region, the chip space depth of the further second and fourth peripheral cutting edge increases.

The outer diameter of the end mill is constant over the length of the cutting (cylindrical) or conical from the front side in the direction of the clamping area.

The diameter can also taper from the end face in the direction of the clamping area.

In a cylindrical end mill with an outer diameter that is the same over the entire length of the cutting edges, the core changes from the end face to the clamping region.

In a conical end mill, the outer diameter of the tip (front) in the direction of the shank (clamping area) increases conically and the core can also in its cross section from a smallest cross section in the region of the tip (front) to a larger cross section at the end of Circumferential cutting in the direction of the clamping area increase, whereby here too the core changes substantially helically from the end face to the clamping area.

Preferably, several or all peripheral cutting edges extend from the end face in the direction of the clamping area in mutually different spiral angles. The spiral angles of adjacent peripheral cutting edges can become larger or smaller in the circumferential direction. Furthermore, the spiral angle of one or more peripheral cutting edges can change over their length.

Furthermore, the cutting edge distances of adjacent or opposite circumferential cutting edges can increase or decrease from the end face to the clamping region.

According to a further embodiment of the invention, a substantially tangential transition is formed in each case between a radial clearance angle of at least one peripheral cutting edge and a tooth back of this circumferential cutting edge. The clearance angle of the cutting edges can also be formed faceted in conventional design. Also, both variants of the design of the clearance angle can be present in an end mill.

The end mill is formed such that the rake angle of the reference blade is made larger than the rake angle of the circumferential sheath of the first peripheral blade type. In an alternative embodiment, the rake angle of the reference cutting edge is smaller than the rake angle of the peripheral scarf of the first peripheral cutting edge type.

With uniform chip space depth of the peripheral cutting the second Umfangsschneidenart the rake angles are also formed uniformly.

Depending on the field of application, different rake angles are different Materials proved to be advantageous. Thus, for machining titanium, the rake angle between 8 ° -18 ° (preferably 10 ° -16 °), which is large compared to the rake angle, and the rake angle 2 ° -7 ° (preferably 5 ° -5 °), which is small compared to the rake angle, are preferably selected ,

For machining high-alloy steels, the rake angle is advantageously selected with a large chip space depth between 5 ° -12 ° (preferably 6 ° to 10 °) and with small chip space depth between 1 ° -7 ° (preferably 3 ° to 6 °). The chip space depth is specified in relation to each other.

When used for machining fiber composite material, for example glass fiber or carbon fiber, the rake angle with large chip space depth between 12 ° - 25 ° preferably 14 ° to 23 °) and with small chip space depth between 8 -16 ° (preferably 10 ° to 14 °) as advantageously result.

It can change the rake angle at a peripheral edge over its length from large to small or from small to large.

Circumferential cutting second Umfangsschneidenart constant chip space depth preferably have a constant rake angle over its length.

The end mill is designed such that the rake angle of the reference cutting edge is preferably reduced from a large rake angle in the region of the end face to a small rake angle in the direction of the clamping region. Consequently, the small rake angle of the peripheral edge cutter of the first peripheral cutter type in the area of the front side is increased to a large rake angle in the direction of the clamping area.

In an alternative embodiment, the end mill is designed such that the rake angle of the reference cutting edge is increased from a small rake angle in the region of the front side to a large rake angle in the direction of the clamping region. Moreover, the large rake angle of the peripheral edge of the first type of peripheral cutting in the region of the end face is limited to a small rake Rake angle is reduced in the direction of the clamping area.

The depth of the reference cutting edges on the front side preferably corresponds substantially to the depth of a peripheral cutting edge of a conventional milling cutter, but may also be deeper or less deep, depending on the machining task.

For example, when machining high-strength materials such as high-alloyed steels, a larger core cross-section is required for a given outside diameter to ensure the required stability - this will select a smaller chip depth of the reference cutters in the stimulus area.

If, for example, GFK, CFRP or a light metal such as aluminum is to be machined with an end mill of the same outside diameter, the chip space depth can be increased for the same outside diameter since the core cross section can be smaller.

The present end mill can consist of HSS, hard metal, cermet, ceramics and all other suitable materials as base material.

Investigations between a conventional milling cutter and the milling cutter according to the invention were able to demonstrate that the tool life of the end mill according to the invention could be more than doubled in comparison to a conventional end mill.

• 1 die Seitenansicht eines Schaftfräsers mit zylindrischem Außendurchmesser und Stirnschneiden nach dem Stand der Technik,
• 2 stimseitige Ansicht gem. 1,
• 3 Schnitt A-A gemäß 1,
• 4 vergrößerte stirnseitige Ansicht gem. 1,
• 5 die Seitenansicht eines erfindungsgemäßen Schaftfräsers mit zylindrischem Außendurchmesser und Stirnschneiden,
• 6 die Stirnseitige Ansicht gem. 5,
• 7 Schnitt B-B gem. 5,
• 8 die Prinzipskizze des Kerns mit den Umfangsschneiden an der Stirnseite und im Schaftbereich des Schaftfräsers,
• 9 den Spanraumverlauf der Zähne 6 und 9 bzw. 7 und 8 in der Seitenansicht, mit sich in Richtung zum Einspannbereich verringernden Abstand,
• 10 den Spanraumverlauf der Zähne 6 und 7 bzw. 8 und 9 in der Seitenansicht, mit sich in Richtung zum Einspannbereich vergrößernden Abstand,
• 11 die stimseitige Ansicht eines Schaftfräsers mit drei Umfangsschneiden,
• 12 die stimseitige Ansicht eines Schaftfräsers mit fünf Umfangsschneiden, davon eine Referenzschneide,
• 13 die stimseitige Ansicht eines Schaftfräsers mit sechs Umfangsschneiden,
• 14 ein Diagramm des Standweges eines herkömmlichen Fräsers mit 6 Umfangsschneiden und des erfindungsgemäßen mit Fräsers mit 4 Umfangsschneiden,
• 15 die Seitenansicht eines zylindrischen Schaftfräsers mit einem Radius in Richtung zur Stirnseite,
• 16 die Seitenansicht eines kegelförmigen Schaftfräsers,
• 17 den Querschnitt C-C gemäß 16,
• 18 den Querschnitt D-D gemäß 16,
• 19 Prinzipdarstellung der Abwicklung einer Referenzschneide und zweier weiterer Umfangsschneiden,
• 20 Prinzipdarstellung der Abwicklung einer weiteren Variante einer Referenzschneide und zweier weiterer Umfangsschneiden,
• 21 die stimseitige Ansicht eines Schaftfräsers mit fünf Umfangsschneiden, davon zwei Referenzschneiden,
• 22 die stimseitige Ansicht eines Schaftfräsers mit fünf Umfangsschneiden, davon drei Referenzschneiden.

The invention will be explained in more detail with reference to embodiments and accompanying drawings. Show it:

• 1 the side view of an end mill with cylindrical outer diameter and end cutting according to the prior art,
• 2 end-face view acc. 1 .
• 3 Section AA according to 1 .
• 4 enlarged frontal view acc. 1 .
• 5 the side view of an end mill according to the invention with cylindrical outer diameter and end cutting,
• 6 the frontal view acc. 5 .
• 7 Section BB gem. 5 .
• 8th the schematic diagram of the core with the peripheral cutting at the front and in the shank region of the end mill,
• 9 the Spanraumverlauf the teeth 6 and 9 or 7 and 8 in the side view, with decreasing towards the clamping area distance,
• 10 the Spanraumverlauf the teeth 6 and 7 or 8 and 9 in the side view, with increasing towards the clamping area distance,
• 11 the end view of an end mill with three peripheral cutting edges,
• 12 the end view of an end mill with five peripheral cutting edges, one of which is a reference cutting edge,
• 13 the end view of an end mill with six peripheral cutting edges,
• 14 a diagram of the life of a conventional milling cutter with 6 peripheral cutting edges and the invention with milling cutter with 4 peripheral cutting edges,
• 15 the side view of a cylindrical end mill with a radius in the direction of the front side,
• 16 the side view of a conical end mill,
• 17 the cross section CC according to 16 .
• 18 the cross section DD according to 16 .
• 19 Schematic representation of the development of a reference cutting edge and two further peripheral cutting edges,
• 20 Schematic representation of the development of a further variant of a reference cutting edge and two further peripheral cutting edges,
• 21 the end view of an end mill with five peripheral cutting edges, two of which are reference cutting edges,
• 22 the end view of an end mill with five peripheral cutting edges, three of which are reference cutting edges.

An end mill 1' in the prior art is in 1 in the side view, in 2 from the direction of the end face 1S 'and in 3 on average A - A according to 1 shown.

The end mill 1' here has four end cutting 1.1 ', 1.2', 1.3 ', 1.4' (see 2 ) to each a peripheral cutting edge 1.1 " . 1.2 " . 1.3 " . 1.4 " followed.

At the front 1S ' opposite end is a clamping area 1E formed, with which the end mill 1 'is clamped in a chuck of a main spindle of a milling machine or a Fräsbearbeitungszentrums. According to this state of the art here are four end cutting 1.1 ' to 1.4 ' and four peripheral cutting 1.1 "to 1.4" provided.

All 4 peripheral cutting edges 1.1 " to 1.4 " wind at a same spiral angle 1W 'around the circular core 11'. From the 2 it can be seen that the two opposite end cutting 1.1 ' and 1.3 ' extend into the center of the end mill, which ensures that a chip removal over the entire end face 1S ' he follows. The shape of the peripheral cutting 1.1 " to 1.4 " is the same thing, especially from 3 can be seen and what is true for all peripheral cutting 1.1 " to 1.4 " gives the same chip space depth t '.

An enlarged view of the end mill 1' according to the prior art from the direction of the front side 1S ' is in 4 shown. It can be seen that the core 11 ' has a circular cross-section with a diameter 11D '.

The outer diameter 1D 'of the end mill is from the front side 1S formed substantially equal to the shaft, resulting in a substantially cylindrical shape of the end mill 1 results.

Furthermore, the rake angle α 'is exemplary on the peripheral edge 1.1 " plotted. The rake angle α 'is at all peripheral cutting 1.1 " to 1.4 " and the same over their entire cutting length.

The frontal cutting 1.1 ' to 1.4 ' and the peripheral cutting edges 1.1 " to 1.4 " have an imbalance Tu 'on. Between a radial clearance angle Wr 'of each peripheral cutting edge 1.1 " to 1.4 " (here only applied to the peripheral edge 1.3 ") and a tooth back this R1" to R4 "of the peripheral cutting 1.1 " to 1.4 " there is an undercut S '.

The power transmission of the chip force F '(bold arrow) is not optimally guided by the undercut behind the peripheral sheath 1.1 "to 1.4" on the non-designated cutting edge. The power transmission is due to the undercut in the radial direction well below the cutting edge on the rake face. Thus, the cutting edge is weakened during chip formation, resulting in a swinging of the cutting edge during the cutting process, which greatly reduces the wear resistance of the end mill and affects the quality of machining.

In the 5 to 7 is a cylindrical end mill according to the invention 1 in 5 in the side view, in 6 in the view from the direction of the front side 1S and in 7 in cross-section BB according to 5 shown. At the front 1S opposite end is according to 5 a clamping area 1E educated.

The end mill according to the invention 1 points to its front 1S here four frontal cutting 2 . 3 . 4 . 5 (S. 6 ) on. To the four frontal cutting edges 2 to 5 close four peripheral cutting edges 6 . 7 . 8th . 9 with rake angles Wα (only on the first peripheral cutting edge 6 submitted). From the direction of the front side 1S become the frontal cutting 2 to 5 and the peripheral cutting edges 2 to 9 numbered consecutively in the clockwise direction. The peripheral cutting 6 to 9 can be executed in any length. In the illustrated embodiment, they extend over a cutting length LS (Please refer 5 ) and have a spiral angle 1W on.

The at the front 1S existing end cutting 2 to 5 , from 6 are apparent, are necessary for the axial machining.

To ensure this, at least one end cutting edge must reach the radial center of the end mill 1 ie to the longitudinal axis A , run. In the example shown ( 6 ) These are the opposite end cutting 2 and 4.

The frontal cutting 3 and 5 and the peripheral cutting edges 7 and 9 have an uneven tooth pitch Tu in the radial section 6 ) to each other.

Out 6 it can be seen that in the area of the front side 1S the first peripheral cutting edge 6 a first chip space depth t6, the second peripheral edge 7 a second chip space depth t7 , the third peripheral cutting edge 8th a third chip space depth t8 and the fourth peripheral cutting edge 9 a fourth chip space depth t9 having. Here, t6 and t8 are substantially the same and t7 and t9 are also substantially the same, with the chip space depths t6 and t8 are larger than the Spanraumtiefen t7 and t9 , In the illustrated variant, the Spanraumtiefen t6 and t8 the opposite circumferential cutting 6 and 8th in the area of the front side 1S about twice as deep as the chip depths t7 and t9. The peripheral cutting 6 and 8th have at the front side the largest Spanraumtiefe t6 . t8 on and form the reference cutting edges R , The other two circumferential cutting edges 7 and 9 have at the front side the smallest Spanraumtiefe t7 and t9 and are in the form of peripheral cutting of the first type U1 formed, ie, the chip space depth changes over the length inversely to the chip space depth of the reference edges R. Due to the different Spanraumtiefen the peripheral cutting 6 to 9 results in an elliptical shape of the core 11 of the end mill 1 ,

The second peripheral cutting edge 7 is radial to the first peripheral edge 6 in a first offset angle a1 arranged, between the second peripheral edge 7 and the third peripheral cutting edge 8th is a second offset angle α2 present, between the third peripheral cutting edge 8th and the fourth peripheral cutting edge 9 is a third offset angle α3 present and between the fourth peripheral cutting edge 9 and the first peripheral cutting edge 6 a fourth offset angle a4 , Here are the first and the third offset angle α1 and α3 less than the second and fourth offset angles α2 and a4 , whereby the distance between the first and the second peripheral cutting edge 6 and 7 and the third and fourth peripheral cutting edges are smaller than the distance between the second and third peripheral cutting edges 7, 8 and the fourth and first peripheral cutting edges 9 . 6 , Furthermore, the tooth back contours 6K to 9K the peripheral cutting edge 6 to 9 different from each other, here the tooth back contours 6K and 8K of the first peripheral sheath 6 and the third peripheral cutting edge 8th are substantially the same and the tooth back contours 7K and 9K of the second circumferential sheath 7 and the fourth peripheral cutting edge 9 are also executed essentially the same.

The chip space depths t6 to t9 and the tooth back contours 6K to 9K can be designed differently and in size variable in deviation from the illustrated embodiment. The core 11 can spiral (spiral) towards the clamping area 1E change, which also from the 6 and 7 evident. In this case, preferably all peripheral cutting 6 to 9 different spiral angles.

Through the chip space depths t6 to t9 and the tooth back contours 6K to 9K in conjunction with the offset angles a1 to a4, different chip space profiles result P1 to P4 that in the 6 and 7 are indicated hatched differently. Between the first and second peripheral cutting edges 6 and 7 is the first chip space profile P2 (Punktschraffierung), between the second and the third peripheral cutting the chip space profile P2 (Dash shading), between the third and the fourth peripheral edge 8th . 9 the chip space profile P3 (Punktschffierung), and between the fourth and the first peripheral cutting the chip space profile P4 (Dashed hatching) formed.

From the comparison of 6 and 7 it can be seen that the in 6 Compared to P2 and P4, the chip space profile is smaller in cross section P1 and P3 due to the changing chip depths in the area of the section BB, which in 7 is shown, are now larger than the chip space profiles P2 and P4 and the chip space profiles P2 and P4 have been reduced. Furthermore, from the 6 and 7 It can be seen that, starting from the end face in the direction of clamping region, the tooth profile of the peripheral cutting edges 6 to 9 changed.

Compared to the in 6 illustrated end face 1S , in which the largest width b1 the ellipse of the core 11 between the vertices S1 and S2 between the shorter here second and fourth peripheral cutting edges 7 and 9 with the here small chip space depths t7 and t9 and the smallest width b2 between the vertices S3 and S4 between the first and third peripheral cutting edges here 6 and 8th with the chip space depths t6 and t8 extends - is from the section BB in 7 it can be seen that by extending over the length of the peripheral cutting edges 6 to 9 changing Spanraumtiefen the first to fourth peripheral cutting edges 6 to 9 that spiral around the core 11 extend, the elliptical core 11 now another position or orientation - here radially about 90 ° offset in the Comparison to the front side - has. The view represented thereby in the region of the section BB clarifies that the second and fourth peripheral cutting edges lower here 7 and 9 (Peripheral cutting of the first kind U1) a larger chip space depth t7 ' and t9 ' and the here shorter first and second peripheral cutting edges 6 and 8 (reference cutting R ) one compared to the Spanraumtiefen t6 and t8 on the front side ( 6 ) smaller chip space depth t6 ' and t8 ' have.

This shows the core 11 in the area of the section BB acc. 7 an orientation on which the largest width b1 the ellipse of the nucleus 11 between the vertices S1 and S2 between the now shorter first and third peripheral cutting edges 6 and 8th with the here small Spanraumtiefen t6 ' and t8 ' and the smallest width b2 between the vertices S3 and S4 between the second lengths now fourth and fourth peripheral cutting edges 7 and 9 with the here larger chip space depths t7 ' and t9 ' extends.

The Spanraumtiefen the first and third peripheral cutting 6 and 8th (Reference Cut R ) can further reduce towards the clamping area and the chip space depths of the second and fourth peripheral cutting edges 7 and 9 (Further peripheral cutting of the first kind U1 ) can continue to increase towards the clamping area.

The first and second chip space depths t6 and t8 the first and third peripheral cutting edges 6 and 8th have thus preferred on the front page 1S a defined size that extends to the clamping area 1E decreased and the second and fourth Spanraumtiefen t7 and t9 the second and fourth peripheral cutting edges 7 and 9 (which are arranged between the peripheral blades 6 and 7) have on the front side 1S a defined size which increases towards the clamping area 1E.

In the illustrated embodiment, the opposing first and third peripheral cutting edges 6 and 8 on the front side 1S essentially the same chip space depth t6 and t8 pointing towards the chuck area 1E to the substantially same Spanraumtiefe t6 ' and t8 ' reduced. Opposite wise have the second and fourth peripheral cutting 7 and 9 at the front 1S essentially the same (smaller) chip space depth t7 and t9 towards the clamping area to the substantially same Spanraumtiefe t7 ' and t9 ' elevated.

The first and third chip space depth t6 and t8 the opposing first and third peripheral cutting edges 6 and 8 at the front side 1S corresponds approximately to the chip space depth t7 ' and t9 ' the intervening third and fourth cutting 7 and 9 towards the clamping area.

The in 7 Specified outer diameter D of the end mill 1 in the area of the peripheral cutting edges 7 to 9 is from the front side 1S towards the clamping area 1E (not apparent here) is essentially the same.

The schematic diagram of the change of the core 11 in the Spanraumtiefe from the direction of the front side 1S towards the clamping area 1E changing circumference shifts 6 to 9 an end mill 1 is in 8th shown. It can be seen that the elliptical core 11 from the direction of the front side 1S in its position towards the clamping area 1E turns and that the size of the peripheral cutting 6 to 9 changed by the changing Spanraumtiefen (not shown here) also. At the end face 1D are the opposing first and third peripheral cutting edges 6 and 8th (Reference Cut R ) larger (deeper) than the intermediate second and fourth peripheral cutting edge 7 and 9 (Further peripheral cutting of the first kind U1 ). Towards the chucking area 1E are the opposing first and third peripheral cutting edges 6 and 8th (Reference cutting R) smaller (flatter) than the intermediate second and fourth peripheral cutting edge 7 and 9 (Circumferential cutting of the first kind U1 ). The core profile also changes in shape from the front to the clamping area. It is also possible that changes the distance of the peripheral cutting over the length of the peripheral cutting.

9 shows the Spanraumverlauf the peripheral cutting 6 and 9 respectively. 7 and 8th in the side view, with towards the clamping area 1E decreasing distance.

Due to the different helix angles change the radial cutting distances of the first and third peripheral cutting edges 6 and 9 and the second and fourth peripheral cutting edges 7 and 8th from the forehead 1S to the clamping area 1E of the end mill 1 asymmetric from big a1 to small a2. Thus, the chip space depths in the shank region of the respective peripheral cutting edges become the clamping region 1E reduced constructively. The Kemabstand the two opposite chip spaces in the shaft area increases. The result is a conically widening core distance ( 8th ).

10 shows the Spanraumverlauf the first and second peripheral edge 6 and 7 or the third and fourth peripheral cutting edge 8th and 9 in the side view, with itself from the front side 1S in the direction of the clamping area 1E increasing distance. Change through the different spiral angles the radial cutting distances of the peripheral cutting from the front side 1S to the clamping area 1E asymmetric from small a2 to big a1. Thus, the chip space depths in the shank region of the respective peripheral cutting edges are structurally enlarged towards the clamping region 1E. The core distance of the two opposite chip spaces in the shaft area decreases. The result is a conically tapering to the shaft core distance. This has the advantage that the second and fourth peripheral cutting edge 7 and 9 towards the clamping area 1E structurally stable can be designed.

The transmission of the chip force or the torque is thus also conducted in a more favorable for the cutting behavior angle to the peripheral edge. This results in a variable and in itself over the length of its shape and position changing core, which can take any possible or arbitrary shape, depending on the changing with respect to the length of the peripheral cutting chip space depth of the peripheral cutting.

Furthermore, the chip space depth of the first and third peripheral cutting edge 6 and 8th and / or the chip space depth of the second and fourth peripheral cutting edges 7 and 9 also completely different among each other. This creates an elliptical or other shaped core. This changes in shape to the shaft, depending on the Spanraumtiefe the peripheral cutting.

The core can thus change in its radial position as a function of the axial position and thereby assume any desired geometric shapes. The core is defined by the chip space depths and the chip space profiles formed between the peripheral cutting edges.

The division / breakdown and shape of the different chip space depths and chip space profiles of the individual peripheral cutting edges can also have any desired variant, depending on the number of peripheral cutting edges.

Due to the greater distance in the end region of the chip space size between the second peripheral cutting edge 7 to the third peripheral cutting edge 8th and between the fourth peripheral cutting edge 9 and the first peripheral cutting edge 6 is the chip space and thus the chip space profile P2 and P4 designed larger than the chip space profile P1 and P3 (please refer 6 ), Since the Abtragbetrag (chip volume) of the material to be machined between each of these two pairs of teeth in the form of peripheral cutting 7 and 8th such as 9 and 6 is larger.

In the stimulus area 1S is between the first peripheral cutting edge 6 and the second peripheral cutting edge 7 and between the third peripheral cutting edge 8th and the fourth peripheral cutting edge 9 the distance is smaller and the removal amount of the material to be cut smaller. Thus, the chip space and therefore also the chip space profile P1 and P3 be made smaller.

This has the advantage that the peripheral cutting 6 and 8th can be made structurally more stable in the forehead area. The transfer of the chip power F (Please refer 6 ) or the torque is characterized in a technically favorable angle on the peripheral cutting 6 to 9 directed.

The different cutting distances are realized by the different offset angle of the peripheral cutting, wherein in the forehead area α1 = α3 smaller α2 = α4 holds (see 6 ) and towards the clamping area α1 = α3 greater α2 = α4 (in 7 not offered).

By the inhomogeneous, shapeless and from the forehead area 1S to the clamping area 1E changing nucleus 11, which in 8th is shown, surprisingly, the bending strength and the torsional stiffness of the end mill 1 clearly increased.

This has an effective Standwegerhöhung and a significant smoothness and anti-vibration effect of the end mill 1 compared to end mills of the prior art by a multiple result.

Due to the elliptical or other (deviating from the circular shape) core, the lateral deflection is significantly reduced in lateral edits, which was proven by scientifically proven studies / tests.

It is possible to use the end mill according to the invention 1 also with three peripheral cutting edges 6 . 7 . 8th ( 11 ) to provide. In the illustrated front view, the first end cutting edge extends 2 to the center of the end mill 1 , Radial joins this the first peripheral cutting edge 6 with a chip space depth t6 at. The first peripheral cutting edge 6 is here as a reference cutting edge R educated. It has the largest chip space depth t6 towards the front side 1S on. In the clockwise direction is then a second peripheral cutting edge 7 with a chip space depth t7 and then the third circumferential sheath 8 with a chip space depth t8 intended. It is in the forehead area t6 > t7 and t6> t8 and t7 = t8. In the direction of the clamping area, not shown here, the chip space depth of the first peripheral cutting edge 6 (reference cutting edge) and the chip space depths of the second and third circumferential sheaths are reduced 7 . 8th are larger, the outer diameter over the length of the peripheral cutting 7 to 9 is essentially constant. The peripheral cutting edges 7 and 8th preferably belong to the first peripheral cutting type U1 at.

Alternatively, according to an embodiment, not shown, one of the two peripheral cutting edges 7 . 8th the first Umfangsschneidenart and the other of the two peripheral cutting edges 7 . 8th belong to the second Umfangsschneidenart.

The chip space depth of the peripheral cutting edge (s) of the second circumferential cutting edge is preferably in the region of the end face between the chip space depth of the reference cutting edge (s) and the peripheral cutting edge (s) of the first peripheral cutting edge type, irrespective of the number of peripheral cutting edges, the chip space depth of the reference cutting edge (n ), increases the chip space depth (s) of the peripheral cutters of the first type, and keeps the chip space depth of the peripheral cutters of the second kind substantially constant.

12 shows an end mill 1 from the direction of the front side 1S with five peripheral cutting edges 6 to 10 , In the illustrated end view, the first end cutting edge extends 2 to the center of the end mill 1 , Radial joins this the first peripheral cutting edge 6 with a chip space depth t6 at. The first peripheral cutting edge 6 is designed here as a reference cutting edge R. It has the largest chip space depth t6 in at the front 1S on. In the clockwise direction is then a second peripheral cutting edge 7 with a chip space depth t7 , a third circumferential divide 8th with a chip space depth t8 , a fourth circumferential divide 9 with a chip space depth t9 and a fifth circumferential divide 10 provided with a chip space t10. In the direction of the clamping area, not shown here, the chip space depth is reduced t6 the first peripheral cutting edge 6 (Reference cutting R ) and the chip space depth t8 and t9 the third and fourth circumference sheaths 8th and 9 (Circumferential cutting of the first kind U1 ) becomes larger, with the outer diameter over the length of the peripheral cutting edges 7 to 10 is essentially constant. The peripheral cutting edges 7 and 10 preferably belong to the second peripheral cutting edge type U2 at, whose Spanraumtiefen t7 , t10 over the length of the end mill 1 are essentially constant.

Alternatively, another number of reference cutting edges, or a different number of further circumferential cutting edges of the first and / or second circumferential cutting edge type, can also be selected.

13 shows an end mill 1 from the direction of the front side 1S with 3 pairs of each diametrically opposite end cutting 2 , 2a, 3, 3a, 4, 4a and peripheral cutting 6 , 6a, 7, 7a, 8, 8a. The diametrically opposite end cutting 2 , 2a reach into the center of the end mill 1 , The chip space depths t6 , t6a of the diametrically opposed peripheral cutting 6 , 6a, the chipspace depths t7 , t7a of the diametrically opposed peripheral cutting 7 , 7a and the chip space depths of the diametrically opposed peripheral cutting edges 8, 8a are substantially equal in pairs. Also not designated here Zahnrückenkonturen the pairwise opposite peripheral cutting edges 6 , 6a, 7, 7a, 8, 8a are designed substantially the same. The peripheral cutting 6 and 6a have the largest chip space depths t6 and t6a and thus form two reference cutting edges R , As in the aforementioned embodiments, the chip space depths change in the direction of the clamping region, not shown here from large to small, while always over the entire length of the peripheral cutting substantially the same outer diameter D is available. Here belong the further peripheral cutting edges 7, 7a of the first peripheral cutting edge type U1 while the other peripheral cutting edges 8th and 8a of the second peripheral cutting type U2 belong.

The rake angles of the individual peripheral cutting edges can be different from each other in all variants. Furthermore, the rake angle of the individual peripheral cutting edges can be variable (not shown). This means that e.g. the rake angle at the forehead starts at 10 ° and ends at 6 ° in the direction of the clamping area or starts at 6 ° and ends at 10 °. The rake angles with one another can be made variable in the end mill. The rake angles can be defined with all possible angular sizes.

Due to the variable rake angle, the cutting process in the cutting area of the respective cutting edge is improved as a function of the chip space geometry of the tooth profile. Due to the special chip spaces between the peripheral cutting edges 6 and 9 (for example, in 5 to 7 ) and between the peripheral cutting edges 7 and 8th In the field of stimulation, the cutting out of the material to be machined is optimized in the case of frontal processing.

The radial clearance angle Wr the peripheral cutting edges and the tooth back contours 6K to 8K ( 6 and 7 ) are characterized by tangential transitions - in contrast to the prior art without undercut. It has the advantage that the torque or the power transmission of the chip force F (see bold arrow in 6 ) is better transferred to the cutting edge of the peripheral cutting (here applied to the cutting edge 8th .S the third peripheral cutting 8).

This stabilizes the cutting area and significantly increases the tool life.

The cutting edges of the heavy duty endmill can be used depending on the application Hard material coatings are provided (eg titanium-aluminum nitrite, titanium-silicon nitride) to further improve its performance.

The present invention of the heavy-duty end mill significantly improves the chip removal rate by increasing the cutting speed and feed rate in mechanical manufacturing.

Due to the geometric peculiarities such as over the length of the peripheral cutting edge changing chip depths, possibly in conjunction with different spiral angles, different pitches in connection with the elliptical or other and the shaft changing core, different and variable Spanraumtiefen, different and variable tooth profiles, different and variable rake angle, asymmetrical course of the peripheral cutting to each other, a Standwegerhöhung is given by a multiple. The optimum chip space structure further favors the cutting out of the material to be machined drastically. The variable elliptical or other shaped core significantly reduces the lateral deflection during lateral processing.

The coordinated design aspects and the perfect interaction of the particularly high-strength materials (substrates) of the end mill, the special cutting geometry and, if necessary, the coating, the described invention is a Hochleistungsschaftfräser with outstanding performance.

In the diagram according to 14 is a performance comparison test of the endurance between an end mill 1' of the prior art with 4 peripheral cutting edges (in the diagram of the upper beam) and a high-performance end mill 1 according to the invention with 4 peripheral cutting edges (lower beam in the diagram).

The cutters had essentially the same outside diameter and lengths and were both made of cemented carbide. The same material (cold work tool steel) was machined with these cutters and the same machining parameters (speed, feed, cutting depth, infeed) were set.

It can be seen that the end mill 1' according to the prior art has already failed after a standstill of 7m, while the end mill according to the invention 1 a footpath of 15-m covered. This is proven that by the end mill according to the invention 1 a superior increase in the endurance s compared to conventional end mills 1' is possible.

Out 15 is a cylindrical end mill according to the invention 1 with four peripheral cutting edges 6 to 9 seen in the side view, in which in the upper half of the side view, the cutting edge at the transition between the peripheral cutting edges 6 to 9 and the end cutting (not designated here) on the front side S1 as a radius HE is trained. According to the dashed contour in the lower half of the section, the transition can also be used as a chamfer EF be educated. Of course, those of an end mill according to the invention with two or more than two circumferential cutting edges in the direction of the shank can preferably also gradually run out with regard to their chip space depth.

The 16 to 18 should clarify that the solution according to the invention also in a conical end mill 1 can be applied. In this case, the outer diameter of a diameter increases D .1 after the tip or the front side 1S towards the clamping area 1E to a diameter D.2 cone-shaped in a cone angle γ and the core may also be in its cross section of a smallest cross section in the region of the front side 1S to a larger cross-section at the end of the peripheral cutting 6, 7, 8, 9 in the direction of the clamping area 1 E increase. Again, the unspecified Spanraumtiefen two substantially opposite handling trimmers 6 and 8th (Reference Cut R ) substantially the same - but different from the here also not designated chip space depths of the other two offset to arranged peripheral cutting edges 7 and 9 (Here two peripheral cutting first Umfangsschneidenart U1), as is the cylindrical end mill in the 6 and 7 was clarified, except that there are no front cutting, since the peripheral cutting 6 to 9 to the radial center in the area of the front side 1S extend. From the cross section CC, in the direction of the front side 1S lies and the cross section D -D moving towards the chuck area 1 E lies, it becomes clear that the outer diameter D .1 enlarged to a diameter D.2. Out 17 it can be seen that in the region of the section CC, the first peripheral cutting edge 6 has a cross-sectional area 6.1 , the second peripheral cutting edge 7 a smaller cross-sectional area 7.1 , the third peripheral cutting edge 8th a cross-sectional area 8.1 , which is essentially the cross-sectional area 6.1 corresponds and the fourth peripheral edge 9 a cross-sectional area 9.1 , which is essentially the cross-sectional area 7.1 corresponds to. The core 11 has an elliptical cross-sectional area 11.1 due to the different depths of the peripheral cutting edge.

The chip space profile P1.1 between the peripheral cutting edges 6 and 7 and P3.1 between the peripheral blades 8 and 9 is approximately equal to and less than the chip space profile P2.1 between Circumferential cutting 7 and 8 and P4.1 between the peripheral cutting edges 9 and 6 where P2.1 and P4.1 are also substantially the same.

From the cross section D - D according to 18 pointing in the direction of the clamping area 1E it is apparent that the first peripheral cutting edge 6 a now smaller cross-sectional area 6.2 , the second peripheral cutting edge 7 a now larger cross-sectional area 7.2, the third peripheral edge 8th a smaller cross-sectional area 8.2 which substantially corresponds to the cross-sectional area 6.2 and the fourth peripheral edge 9 a larger cross-sectional area here 9.2 , which is essentially the cross-sectional area 7.2 corresponds to. It can be seen that the unspecified chip space depths of the first and third peripheral cutting edges 6 and 8th (Reference Cut R ) reduce from the front side in the direction of the clamping area and the chip space depths of the second and fourth peripheral cutting edges 7 and 9 (Circumferential cutting first Umfangsschneidenart U1 ) is enlarged from the front side in the direction of the clamping area. The elliptical core 11 is rotated in its orientation by approximately 90 ° and has a larger compared to the cross-sectional area 11.1 cross-sectional area 11.2 on.

The chip space profile P1.2 between the peripheral cutting edges 6 and 7 and P3.2 between the peripheral blades 8 and 9 is now larger than the chip space profile P2.2 between the peripheral cutting edges 7 and 8th and P4.2 between the peripheral cutting edges 9 and 6 , Due to the conical shape, however, the overall chip space profile is in the direction of the clamping area 1E in the sum of P1.2 + P2.2 + P3.2 + P4.2 greater than the chip space profile in the sum P1.1 + P2.1 + P3.1 + P4.1 towards the frontal area, since this corresponds to the conical shape is scaled with.

According to an embodiment, not shown, a conical end mill according to the invention may also be provided with end cutting and from the transition from the outer diameter to the end face have a radius or a chamfer.

Instead of in 16 to 18 As illustrated, a tapered end mill may also have a different number of peripheral cutting edges, eg 2, 3, 5, 6 and more than 6.

A tapered end mill whose peripheral cutting edges have a chip space depth varying from the tip / end side toward the clamping region realizes the same advantages as a substantially cylindrical outer diameter end mill according to FIG 5 to 14 , The conical end mill may also have one or more reference cutters which are combined with one or more further peripheral cutters of the first circumferential cut type, wherein in addition one or more peripheral cutters of the second circumferential cut type may be provided.

19 shows a general schematic representation of the settlement of a reference cutting edge 6R and two other peripheral cutting edges along the cutting edge LS , It is in the illustrated embodiment to unwinds of peripheral cutting a cylindrical end mill, wherein the outer diameter D from the top / front 1S of the end mill towards the clamping area 1E of the end mill is substantially constant. Also shown is the core diameter DK at the respective peripheral cutting edge. The chip space depth tR _{S of} the reference cutting edge R decreases from the top / front 1S towards the clamping area 1E of the end mill to a chip space depth tR _E , The first additional peripheral cutting edge U1 is of another first type of peripheral cutting. Your chip space depth tU1 _s increases from the top / front 1S in the direction of the clamping region 1E of the end mill to a chip space depth tU1 _E , The second additional peripheral cutting edge U2 is of another second peripheral cutting type. Their chip space depth tU2 _s extends from the top / front side 1S towards the clamping area 1 _E (of the end mill to the chip space depth tU2 _E = tU2 _p consistently.

The chip space depth of the second Umfangsschneidenart lies on the front side and in the direction of the clamping area between the Spanraumtiefen the reference blade and the peripheral edge of the first Umfangsschneidenart.

Viewed from the front side, the chip space depth is reduced tR _s a reference cutting edge R until its end at the clamping area 1 _E on a chip space depth tR _E = 10% to 50% of tR _s , preferably 15% to 30% of tR _s , in particular to 25% of tR _s , Conversely, the first type of peripheral cutting increases U1 from the end face 1S starting with a chip space depth tU1s in the direction of the clamping area 1E to the chip depth tU1E.

The chip space depth tU2 _s is starting from the end face 1S towards the clamping area 1E (there tU2 _E ) 20% to 80% of tR _s , preferably 40% to 60% of tR _s , in particular 50% of tR _s ,

According to 19 the chip space depth reduces / increases linearly at the reference cutting edge R and at the first cutting edge cutter U1 However, it is also possible that this is reduced / increased in another course.

According to 20 it is also possible that the Spanraumtiefe the reference cutting edge R from tRs already up to a range of cutting edge length LS1 < LS to the chip depth tR _E reduced and then with this Spanraumtiefe tR _E towards the clamping area 1E continues.

In this case, the chip space depth increases tU1 _s the circumferential cutting edge of the first peripheral cutting type U1 _s up to a portion of the cutting edge length LS1 < LS to the chip depth tU1 _E and then runs with this Spanraumtiefe tU1 _E towards the clamping area 1E further. In the example shown is LS1 about 50% of LS ,

Preferably corresponds to the 19 and 20 the chip space depth tU1 _s the further peripheral edge of the first Umfangsschneidenart U1 at the front 1S essentially the chip space depth tR _E the reference cutting edge R towards the clamping area 1E and the chip space depth tU1 _E the further peripheral edge of the first peripheral cutting U1 towards the clamping area 1E essentially the chip space depth tR _s the reference edge R at the front 1S ,

However, it may also be advantageous if the Spanraumtiefe tU1 _E the further peripheral edge of the first peripheral cutting U1 towards the clamping area 1E is smaller than tRs, since then the core in the direction of the clamping region 1E has a larger cross-section, which is advantageous for some applications. In this case, the chip space depth tU1 _E reduced to preferably up to 0,7 xtRs, which in the 19 and 20 indicated by the semicolon line.

Furthermore, it is possible according to an embodiment, not shown, that the chip space depth of a reference edge of the front side only evenly with the same Spanraumtiefe and then reduced towards the clamping and that the chip space depth of a peripheral cutting first Umfangsschneidenart only from the front side with a same Spanraumtiefe extends and then increases the Spanraumtiefe from a certain cutting length.

In general, the milling cutter according to the invention should have at least one circumferential cutting edge in the form of a reference cutting edge and at least one further peripheral cutting edge in the form of a first circumferential cutting edge shape. These may be combined with at least one further circumferential cutting edge second Umfangsschneidenart.

For the sake of good order, further variants of a milling cutter with 5 peripheral cutting edges are described below. In 21 is from the direction of the front side 1S a cutter shown which 2 reference cutting R having. These are the peripheral cutting edge located here 6 and the third peripheral cutting edge 9, starting therefrom in the clockwise direction. Clockwise, the peripheral cutting edge closes 6 another peripheral cutting edge 7 second peripheral cutting type U2 on which another circumferential cutting edge 8th in the form of a first peripheral cutting type U1 follows. Between the peripheral cutting edges 6 and 9 that as reference cutting R are executed, is another peripheral cutting edge 10 arranged as the first Umfangsschneidenart U1 is executed.

22 shows an example of an end mill with 5 peripheral cutting edges, of which three are designed as reference cutting edges R. These are the peripheral cutting edge located here 6 and the clockwise from the next circumferential cutting edge 8th and then circumferentially adjoining peripheral cutting edge 9 , Between the peripheral cutting edges 6 and 8th (Reference Cut R ) is another peripheral cutting edge 7 the second Umfangsschneidenart U2 arranged - in their place could also be provided a further peripheral edge of the first Umfangsschneidenart - and between the peripheral cutting edges 6 and 9 (Reference Cut R ) another peripheral cutting edge 10 first peripheral cutting type U1 , The Spanraumtiefen were in the 21 and 22 not offered.

According to an embodiment, not shown, regardless of the number of peripheral cutting some or all peripheral cutting edges have different chip depths. The chip space size, the chip space profile as well as the tooth size and the tooth profile of the different types of peripheral cutting edges are different from one another and change in the course of the forehead to the clamping area.

The clearance angle training in the form of radial relief with a substantially tangential transition or a facet-shaped design of the clearance angle offers an additional advantage.

With the solution according to the invention, a new type of high-performance milling cutters is created, in which the chip space depth of at least one first peripheral edge changes for the first time from the tip / end side in the direction of the clamping region, and the chip space depth changes in the opposite direction for at least one further circumferential cutting edge. This new and inventive constructive design a significant increase in the life cycle is feasible compared to conventional milling cutters.

LIST OF REFERENCE NUMBERS

• State of the art 1 to 4 :

  1'

  End mills

  1D '

  Outside diameter in the area of the peripheral cutting

  1S '

  front

  1.1 ', 1.2', 1.3 ', 1.4'

  face cutting

  1.1 ", 1.2", 1.3 ", 1.4"

  peripheral cutting edge

  11 '

  core

  11D '

  Diameter of the core

  1E '

  clamping

  t '

  Chip space depth

  α '

  rake angle

  Tu '

  unequal division

  Wr '

  radial clearance angle

  R1 "to R4"

  tooth back

  S '

  Freeway

  F '

  tension

  KS "

  cutting edge

• Inventive solution 5 to 22 :

  1

  End mills

  1S

  front

  1E

  clamping

  1W

  helix angle

  2, 3, 4, 5, 12

  face cutting

  2-2a, 3-3a, 4-4a

  pairs of opposite frontal cutting

  6-6a, 7-7a, 8-8a

  in pairs opposite circumferential cutting

  6

  first peripheral cutting edge / reference cutting edge

  7

  second peripheral cutting edge

  8th

  third peripheral cutting edge

  8S

  cutting edge

  9

  fourth peripheral cutting edge

  10

  fifth peripheral cutting edge

  6K to 9K

  Tooth back contours of the peripheral cutting edges 6 till 9

  11

  core

  6.1, 7.1, 8.1, 9.1,

  Cross-sectional areas of the peripheral cutting edges 6 . 7 . 8th . 9 towards the front side 1S a conical end mill 1

  6.2, 7.2, 8.2, 9.2

  Cross-sectional areas of the peripheral cutting edges 6 . 7 . 8th . 9 towards the clamping area 1E a conical end mill 1

  11.1

  Cross-sectional area of the core 11 towards the front side 1S a conical end mill 1

  11.2

  Cross-sectional area of the core 11 towards the clamping area 1E a conical end mill 1

  a1

  large distance between the peripheral cutting edges

  a2

  small distance between the peripheral cutting edges

  b1

  Width of the ellipse of the core between the vertices S1 and S2

  b2

  Width of the ellipse of the core between the vertices S3 and S4

  A

  longitudinal axis

  D

  outer diameter

  D1

  outer diameter

  D2

  outer diameter

  DK

  core diameter

  EF

  chamfer

  HE

  radius

  F

  tension

  L

  Overall length of the end mill 1

  LS

  cutting length

  LS1

  Range of cutting length LS1

  P1, P2, P3, P4

  Chip space profile

  P1.1, P2.1, P3.1, P4.1

  Chip space profile towards the front 1S a conical end mill 1

  P1.2, P2.2, P3.2, P4.2

  Chip space profile towards the clamping area 1E a conical end mill 1

  R

  reference cutting

  S

  Tool life

  t6

  first chip space depth

  t7

  second chip space depth

  t8

  third chip space depth

  t9

  fourth chip space depth

  t7 'and t9'

  greater chip space depth

  t6 'and t8'

  smaller chip space depth

  Tu

  unequal tooth pitch

  tR _s

  Chip space depth of the reference cutting edge on the front side

  tR _E

  Chip space depth of the reference cutting edge in the direction of the clamping area

  tU1 _s

  Spanraumtiefe the first Umfangsschneidenart on the front page

  tU1 _E

  Spanraumtiefe the first Umfangsschneidenart towards the clamping area

  tU2 _p

  Spanraumtiefe the second Umfangsschneidenart on the front page

  tU2 _E

  Spanraumtiefe second Umfangsschneidenart towards the clamping area

  U1

  first circumferential cutting type

  U2

  second peripheral cutting type

  Wr

  radial clearance angle

  Wα

  rake angle

  α1

  first offset angle

  α2

  second offset angle

  α3

  third offset angle

  a4

  fourth offset angle

  γ

  cone angle

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102015214964 A1 [0003]
• DE 20023770 U1 [0004]
• DE 10243403 A1 [0005]
• AT 14275 U1 [0006]
• JP 2007136627 A [0007]

Claims (15)

End mill (1) having a core (11) on which circumferentially connect at least two peripheral cutting, wherein a chip space is defined by one peripheral cutting edge, characterized in that at least one peripheral cutting edge forms a reference edge (R) and - the chip space depth of at least a reference cutting edge (R) from the direction of an end face (1S) of the end mill (1) in the direction of a clamping region (1E) of the end mill (1) is reduced at least partially and - the chip space depth of at least one further peripheral cutting edge of a first peripheral cutting edge type (U1) is from the direction the end face (1S) of the end mill (1) in the direction of the clamping region (1E) of the end mill (1) at least partially increased. End mill (1) after Claim 1 , characterized in that - the chip space depth (tR _s ) of the reference cutting edge (R) over the entire length (LS) or a length range (Ls1) is reduced to a chip space depth (tR _E ) and - that the chip space depth (tU1 _S ) the further peripheral edge of the first peripheral cutting edge type (U1) over the entire length (LS) or the length range (Ls1) of the reference cutting edge (R) is increased to a chip space depth (tU1 _E ) opposite to the profile of the chip space depth of the reference cutting edge (R). End mill after Claim 1 or 2 Characterized in that - the chip space depth of the reference edge (R) and the chip space depth of the at least one further peripheral cutting edge of the first Umfangsschneidenart (U1) from the front side (1S) of the end mill (1) towards a clamping region (1E) of the end mill (1) runs evenly and then reduces / increases in the direction of the clamping area or - that chip space depth of the reference cutting edge (R) and the Spanraumtiefe the at least one other peripheral edge of the first Umfangsschneidenart (U1) starting from the end face (1S) of the end mill (1) in Direction to a chucking (1 E) of the end mill (1) first reduced / increased and then runs evenly to the chucking or - that chip space depth of the reference cutting edge (R) and the Spanraumtiefe the at least one further peripheral edge of the first Umfangsschneidenart (U1) of the End face (1S) of the end mill (1) up to the clamping area (1 E) of the shank milling cutter sers (1) reduced / increased. End mill according to one of the Claims 1 to 3 , characterized in that the chip space depth (tU1 _S ) of the further peripheral cutting edge of the first peripheral cutting edge type (U1) on the end face (1S) substantially corresponds to the chip space depth (tR _E ) of the reference cutting edge (R) in the direction of the clamping region (1 E) and - that the chip space depth (tU1 _E ) of the further peripheral cutting edge of the first peripheral cutting edge type (U1) in the direction of the clamping region (1 E) substantially corresponds to the chip space depth (tR _S ) of the reference cutting edge (R) on the end face (1S) or is smaller than ( TRS). End mill according to one of the Claims 1 to 4 characterized in that it comprises at least one reference cutting edge (R), at least one further first cutting edge type (U1) and at least one further second cutting edge type (U2), the chip space depth of the peripheral cutting edge of the further second cutting edge type (U2) from the end face (1S) of the end mill (1) runs in the direction of the clamping area (1E) of the end mill (1) in a constant or essentially constant manner. End mill (1) after one of the Claims 1 to 5 , characterized in that the reduction of the chip space depth of the at least one reference cutting edge and / or increase of the chip space depth of the at least one further peripheral cutting edge of the first Umfangsschneidenart of the end face (1S) of the end mill (1) in the direction of the clamping region (1 E) of the end mill (1 ) is linear. End mill (1) after one of the Claims 1 to 6 , characterized in that the core (11) of the end mill (1) in cross section at least partially deviates from a circular shape and extending in the deviating from the circular length range starting from the end face (1S) in the direction of the clamping region (1E) spirally. End mill (1) after one of the Claims 1 to 7 , characterized in that the rake angles (Wα) of at least two circumferential sheaths are different from one another and / or that the rake angle (Wα) of at least one circumferential cutting edge changes from the stimulus region (1S) to the clamping region (1E). End mill (1) after one of Claims 1 to 8th Characterized in - that it has exactly three peripheral cutting edges, wherein ○ a peripheral cutting edge is the cutting edge or reference ○ two peripheral cutting edges are the reference, or - that it has exactly four peripheral cutting edges, wherein two opposite Circumferential cutting edges are the reference cutting edges and between each two reference cutting edges a respective peripheral cutting edge is arranged or - that has exactly five peripheral cutting edges, o a circumferential cutting edge being the reference cutting edge whereby at least one of the further four peripheral cutting edges is a further peripheral cutting edge of the first circumferential cutting edge or o two circumferential cutting edges Reference cutting are and in each case between the two reference cutting edges once another peripheral cutting and once two adjacent further peripheral cutting are arranged or three peripheral cutting edges are the reference cutting edges and two reference cutting edges adjacent to each other and between the two adjacent and the third reference cutting edge in each case a further peripheral cutting edge is arranged or - that it has exactly six peripheral cutting edges, where o at least one peripheral cutting edge is a reference cutting edge and at least one of the further five Circumferential cutting is a further circumferential cutting edge of the first peripheral cutting edge type or o at least two peripheral cutting edges are the reference cutting edges and further peripheral cutting edges are arranged between the reference cutting edges wherein at least one further peripheral cutting edge is a peripheral cutting edge of the first peripheral cutting edge type or three peripheral cutting edges are the reference cutting edges, each between two reference cutting edges Circumferential cutting is arranged and wherein at least one of the further peripheral cutting edges is a peripheral edge of the first Umfangsschneidenart. End mill (1) after one of the Claims 1 to 9 , characterized in that the cutting edge distances of adjacent or opposite circumferential cutting edges from the end face (1S) to the clamping area (1 E) increase or decrease. End mill (1) after one of the Claims 1 to 10 , characterized in that in each case between a radial clearance angle (Wr) of at least one peripheral cutting edge and a tooth back of this circumferential cutting a substantially tangential transition is formed and / or that the clearance angles are formed in the form of facets. End mill (1) after one of the Claims 1 to 11 characterized in that the rake angle (Wα) of the reference blade (R) is equal to, greater than or less than the rake angle (Wα ') of the circumferential sheath of the first peripheral blade type and / or the rake angle (Wα) of the reference blade (R) and / or the rake angle (Wα ') of the circumferential sheath of the first peripheral cutting type (U1) changes over the cutting length / n thereof. End mill (1) after one of the Claims 1 to 12 , characterized in that at a uniform chip space depth of the rake angle (Wα) of the peripheral cutting of the second Umfangsschneidenart (U2) is uniform. End mill (1) after one of the Claims 1 to 13 , characterized in that - for the machining of titanium, the rake angle 8 -18 °, which is large compared to the rake angle (Wα), and the rake angle small 2-7 ° in comparison to the rake angle, or - that for raking high-alloy steels the rake angle (Wα ) with a large chip space depth between 5 -12 ° and with small chip space depth between 1 - 7 °, or - that for the processing of fiber composite material that the rake angle (Wα) with large chip space depth between 12 - 25 ° and with small Spanraumtiefe between 8 -16 ° is. End mill according to one of the Claims 1 to 14 Characterized in - that the rake angle (Wα) (R) by a large rake angle in the region of the end side (1S) of a small rake angle (Wα) in the direction of the clamping area (1 E) is reduced to the reference cutting edge and that the small rake angle ( Wα ') of the peripheral edge of the first Umfangsschneidenart (U1) in the region of the end face (1S) to a large rake angle (Wα') in the direction of the Einspannbereichs (1 E) is increased or - that the rake angle (Wα) of the reference edge (R) of a small rake angle (Wα) in the region of the end face (1S) is increased to a large rake angle (Wα) in the direction of the clamping region (1 E), and that the large rake angle (Wα ') of the peripheral edge cutting edge (U1) is in the region of End face (1S) is reduced to a small rake angle (Wα) in the direction of the clamping area (1 E).

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