DE10308037B4 - Rotary cutting tool, in particular milling tool - Google Patents

Abstract

rotating Cutting tool, in particular milling tool, with a support body rotating about a vertical axis, at its periphery Has recordings for the fixed attachment of inserts or cassettes with recordings for inserts, wherein at the periphery of the carrier body each other following, arranged on the same axis inserts with an angle offset cutting edges by a certain angle against each other are twisted that by different trajectories of the cutting edges forced a separation of abzuspanenden workpiece allowance in several chips is, characterized in that the cutting plates (26, 40) polygonal are formed, at least every second receptacle in the carrier body or in the cassette so is that an insert (26, 40) optionally in one of two Rotary positions can be determined and seat surfaces (28, 30, 46, 48) of the recordings (24, 42) for a rotational position recesses (32, 34, 50, 52) are formed, whose surfaces seats for one second rotational position of the (26 40), forming the cutting plate.

Description

The The invention relates to a rotary cutting tool, in particular Milling tool, after the preamble of claim 1.

Cutting tools, in particular milling tools, enable an implementation of their high performance only at stable processing conditions. In practice, such conditions are rare. In the machining the dynamics of the process play a big role. The system elements Machine, workpiece, Tool and the clamping means of workpiece and tool practice simultaneously an impact on the dynamics.

considered one the physical force system, then it comes through during the milling the interrupted cut to a periodic impact of the cutting edges on the workpiece, whereby a forced oscillation with a certain frequency and a power-dependent one Amplitude is caused. The acting force impulses result in interaction with the other system elements and the set cutting values to inevitable vibration phenomena up to the so-called "chattering", whereby the processing clearly complicated and run only with relatively low productivity can. Naturally there is Reasons for unstable conditions on the part of the machine, the workpiece and the clamping device, which is not to be examined here in detail. In the milling process become vibrations due to the cutting forces emitted by the tool caused in the system. The effects depend on the size of the forces and from the impact hardness from. In order to achieve optimal dynamic conditions, it is advisable to make the mass of the cutter body large, the milling base body antivibration To produce materials, an unequal division of the cutting edges cutters scope to minimize the impact conditions (large inclination and rake angle), a selection of cutting values with small chip width and big Chip thickness and cutting division, e.g. by Grinding division notches.

Out DE 100 12 101 A1 is a radius cutting plate has become known, in which the conical surface has flat surfaces. By an angular offset of successive inserts a cut distribution is achieved. Out DE 23 41 183 B a tool has become known in which in the circumferential direction of the tool successive cutting inserts in corresponding recesses in different angular positions can be fixed. The positioning means are formed by pins projecting into the recesses which are engageable with cutting tooth gaps of the cutting inserts.

Of the Invention is based on the object, a rotating cutting tool, in particular milling tool to create a dynamically stable process.

These The object is solved by the features of claim 1.

at the cutting tool according to the invention are as in the prior art on the circumference of the carrier body following each other, on the same axis arranged inserts by a certain angle so twisted against each other, that by different trajectories the cutting edges a separation of the abspanenden material piece allowance in several Shavings forced becomes. The inserts are polygonal in the invention. Thereby the cut division is done by a coaxial cutting penetration of polygonal inserts. The principle is based on that the inserts lying on the same axis to a certain Angle so twisted against each other that the different Trajectories force a separation into several chips. It is known, that a cut division by reducing the Spanungsbreite with simultaneous increase the chip thickness the milling process clearly stabilized.

For the cutting plate can be a usual indexable insert be used of polygonal shape. However, it is preferable after According to one embodiment of the invention, an insert of equal edge length, e.g. a square, hexagonal or octagonal insert. Preferably the inserts are in pairs twisted in pairs Rotational position arranged. In other words, in the circumferential direction saw every next but one insert the same rotational position as the starting cutting plate. The intervening Cutting inserts are each rotated by a certain angle. For an octahedron plate this is Angle 22.5 ° and with a square plate 45 °. In a square cutting plate in the inventive application after all, there is a possible Span division of three chips. An octahedron plate results in a maximum number of chips five.

Since the susceptibility to vibration in the system increases with the number of teeth, with the principle of the simultaneous increase of the chip divisions an effective measure for dynamic stability is achieved. The coaxial penetration is particularly particular with an octahedral indexable insert effective for milling jobs where large cutting depths are required in one operation or large tool protrusions are required. Such applications are present when milling pockets and Auskoffern of dies. Even plunge milling can be designed economically, since even in Werkzeugachsrichtung a cut division is enforced.

The Invention is for both Mono version (attachment the inserts directly on the body) as well as in cassette design advantageous. For the cassette version takes the body known in recordings on individual cassettes, in turn then recordings for having the cutting plates.

According to the invention Shooting in the main body designed so that they are the polygonal inserts in at least can record two different rotational positions. For this purpose are in seats of the Recordings for formed a rotational position recesses whose surfaces seat surfaces for the second rotational position of the Forming inserts. Such a design of the body requires naturally such Training the shots only for the next but two shots, while the intervening recordings are conventionally executed can. Such a design of the body has the advantage that with the same tool and the same indexable inserts both without as well as can be worked with cut division. Leave it Stability in the System to, can be milled without cutting division (all indexable inserts are in normal position without rotation). Here comes It does not lead to a doubling of the tooth feed and the danger an overload the cutting can be avoided. On the other hand, there are unstable milling conditions before or are great To handle cutting depths, then the user can in a few minutes by twisting each one second indexable insert realize the coaxial cutting penetration, without having to make a tool change. It should be noted that the tooth feed doubles, but in the interest of the dynamic stability quite wanted.

The The invention will be explained in more detail with reference to drawings.

1 schematically shows the operation of the milling tool according to the invention with octahedral inserts.

2 shows schematically the operation of a milling tool according to the invention with square inserts.

3a and 3b show a plate seat in a base body of the milling tool according to the invention with a plate seat for receiving square inserts.

4a and 4b show the main body of the milling tool according to the invention with a plate seat for receiving an octahedron cutting plate.

In 1 is a first octahedral indexable insert 10 indicated as well as a second octahedral indexable insert 12 , You are in a basic body, not shown in circumferentially consecutive shots or pockets of the body. As can be seen, the indexable inserts 10 . 12 rotated by 22.5 ° to each other, but are on one axis. The workpiece is at 14 indicated. In addition, the contour is indicated by hatching, the successive chipping with the inserts 10 and 12 arises.

One recognizes 1 in that, as the depth of cut increases, the number of divisions of the resulting chips increases. At maximum depth of cut, a chip count of five is achieved. In this way, a high dynamic stability is achieved at large depths of cut.

In 2 is a first square indexable insert 16 and a second square indexable insert 18 represented, which are clamped in succession on the circumference of a carrier body not shown. The indexable inserts 16 . 18 lie on an axis, but are rotated by 45 ° to each other. Here too, an axial penetration is provided and dynamic stability is achieved with a maximum number of chips of three. The workpiece is with 20 indicated, and recognizable by the hatched broken line, the contour that when engaging with the inserts 16 . 18 is produced.

Depending on the diameter and design of the carrier body, a plurality of inserts 10 . 12 respectively. 16 . 18 be included, but this is not shown in detail here. The recording of the inserts 10 . 12 respectively. 16 . 18 takes place directly in corresponding recesses, pockets or seats of the body or in cassettes, which are mounted in recesses of the body. The various types of mounting plates directly (mono-run) or cassettes are well known. In the 3 and 4 the arrangement in mono is shown for square and octahedral indexable inserts.

In 3 is at 22 a body indicated with a pickup or bag 24 for the up a square indexable insert 26 , 3b shows the normal recording of the indexable insert 26 (Cutting edge 2). 3a shows the 45 ° twisted indexable insert 26 (Cutting edge 1). The bags or shots 24 are in the desired pitch on the carrier body 22 intended. The cutting 1 and 2 follow alternately seen in the circumferential direction.

You can see that in the seats 28 . 30 recesses 32 . 34 are shaped, which seats 36 respectively. 38 form. They serve to define the cutting edge 1 according to 3a , One recognizes that a milling process either with the cutting edges 26 can be made in the normal position or in the manner according to the invention, in which the rotational positions of the cutting 26 alternate at the circumference of the body. It is only at every second recess 24 the formation of the recesses 32 . 34 required to realize the described mode of action.

In the embodiment according to 4 is according to 4a an octahedron indexable insert 40 in normal rotational position and the indexable insert 40 from the same training in a 22.5 ° twisted position in a recording 42 of a basic body 44 arranged. To lay down in 4 are only the seats 46 respectively. 48 required. At a twist of 22.5 ° seating surfaces act 50 respectively. 52 with the cutting edge 2 together to set the octahedron plate in this rotational position. The training of recordings, plate seats or the like 4a and 4b is with regard to additional seating areas 50 . 52 only required for every second shot.

Also in the 3 and 4 are the clamping devices for fixing the plates 26 or 40 not shown. They can be of conventional education.

Claims (2)

Rotary cutting tool, in particular milling tool, with a rotating about a vertical axis carrier body having receptacles on its periphery for the fixed attachment of inserts or cassettes with recordings for inserts, wherein the circumference of the support body following each other, arranged on the same axis inserts with a Angle offset cutting edges are rotated by a certain angle to each other so that is enforced by different trajectories of the cutting edges separation of abzuspanenden workpiece allowance in several chips, characterized in that the inserts ( 26 . 40 ) are polygonal, at least every second receptacle in the carrier body or in the cassette is shaped so that an insert ( 26 . 40 ) is selectively fixable in one of two rotational positions and in seating surfaces ( 28 . 30 . 46 . 48 ) of the recordings ( 24 . 42 ) for a rotational position recesses ( 32 . 34 . 50 . 52 ) whose surfaces seat surfaces for a second rotational position of the ( 26 40 ), Forming the cutting plate. Cutting tool according to claim 1, characterized in that cutting inserts ( 26 . 40 ) are provided the same edge length.