DK2251164T3 - Cutting tool - Google Patents

Abstract

The tool has a base body (3) rotatably driven around a rotational axis and arranged in a circumferential region (4) of cutting teeth (5). The cutting teeth include a circumferential cutting region (6) and protrude on the circumferential cutting region adjacent to a cutting projection (7) relative to the rotational axis in an axial direction over the base body. The cutting teeth are radially arranged within the cutting projection, and another set of cutting projections (8, 9) is projected in the axial direction over the base body.

Description

Description [0001] The invention relates to the use of a chipping tool for formatting plates, in particular of a wood-type material, with the features of the preamble of claim 1. Such a use is disclosed in DE 101 07 881. Plates of wood-type materials, such as chipboard or the like, are machined and brought into shape by a rotationally driven chipping tool. One working step in the process is the formatting, in which straight edges in particular are to be produced cleanly and free of spalling by means of a suitable chipping tool.

[0002] Such chipping tools comprise a base body, on the periphery of which cutting teeth are arranged, wherein each of the cutting teeth comprises a peripheral blade and a cutting projection which, relative to the axis of rotation, projects beyond the base body in the axial direction and adjoins the peripheral blade. Producing a relatively great chipping volume, the blades act both on the peripheral side and on the end face facing the workpiece, with the aim of achieving as clean a cut face as possible.

[0003] From DE 101 07 881, a generic chipping tool is known, the peripheral blades and the end blades of which merge with sharp edges, the peripheral blades having a linear shape. The corner region between the peripheral blades and the adjoining end blades form the cutting projection which projects beyond an the base body in the axial direction and the properties of which determine the target quality of the cut face. In the illustrated arrangement, various disadvantage are to be observed. The transition between end and peripheral blades is sensitive to blows. Foreign bodies enclosed in the chipboard can lead to spalling in this quality-forming blade region. In this case, the desired cut face quality is no longer achieved. Moreover, the usual wear has comparable effects. If blade corners are rounded and made blunt by wear, the chipboard can no longer be cut cleanly. The results are ruptures at the plate cover layers and defects in the central layers of the chipboard. Chips which are not cut cleanly remain at the workpiece, yield initially and then upright themselves in an undesirable way, which affects the cutting result as well.

[0004] DE 10 2004 012 619 A1 discloses a tool with a base body and cutting teeth having a first cutting projection and a second cutting projection. The tool is used for producing drill dust grooves in drills, with only the first cutting projections being used in operation. The second cutting projections project beyond the base body in the axial direction without fulfilling any function. They are only kept available to replace worn first cutting projections and, if required, brought into operating position by rotating the mounting position of the cutting plates.

[0005] The invention is based on the problem of specifying a chipping tool for use in formatting plates in such a way that the cut quality is improved and maintained for a longer service life.

[0006] This problem is solved by the use of a chipping tool with the features of claim 1.

[0007] For this purpose, the use of a tool is proposed in which the cutting teeth comprise, radially inward of the axially projecting cutting projection, at least a second and preferably at least a third cutting projection projecting beyond an end face of the base body in the axial direction. The radially inward cutting projection is preferably offset in the axial direction and in particular set back against the adjacent radially outward cutting projection.

[0008] The radially inward and the radially outward cutting projections support one another. Individual chips which are not cut cleanly by the radially outward cutting projections are eventually severed cleanly by the radially inward cutting projections and vice versa. This mutual supporting action is maintained even as wear occurs, so that the service life of the chipping tool is increased. The axial offset between the radially outward and the radially inward cutting projections has the result that the cutting projections which project further in the axial direction are initially used preferentially. This subjects them to normal operating wear, while the set back cutting projections are loaded less and their wear starts later. With increasing wear of the in particular radially outward cutting projections, the set back radially inward cutting projections are increasingly used. Thanks to the not yet present or lesser wear, they have the required sharpness for producing the desired clean cut result. The axial offset therefore results in wear which is sequentially graduated over the service life of the tool, so that at least in the radially inward region sufficiently sharp cutting projections will be available at the end face of the chipping tool for a significantly longer service life.

[0009] In an advantageous further development, the cutting projections of an individual cutting tooth lie on a straight line, which is inclined by an angle relative to a radial direction perpendicular to the axis of rotation. The angle lies preferably in a range of 0.5° to 2.0° inclusive and is in particular approximately 1.0°. On the one hand, in this arrangement a good mutual support action of the radially outward and the radially inward cutting projections can be observed. On the other hand, if the radially outward cutting projections begin to be worn, the radially inward, still sharp, cutting projections seamlessly take over the chipping function.

[0010] In a preferred embodiment, the cutting projections have axially outward points. The points are designed to be asymmetric in particular. Alternatively or in combination, it can be expedient that the cutting projections have a contour with a rounded wave shape. Both embodiments lead to a clean, spall-free result combined with a significantly longer service life.

[0011] It can be expedient that the peripheral blade forms the radially outermost axially projecting cutting projection by means of its axially projecting corner.

Preferably, however, a chamfer is arranged between the radially outward cutting projection and the peripheral blade. The chamfer reduces the blade's sensitivity to blows. The risk of blade spalling is reduced, so that the quality of the cut face can be ensured more reliably. An embodiment in which the peripheral blade is inclined towards the axis of rotation in the direction towards the cutting projection contributes to a further improvement of the cut result.

[0012] Embodiments of the invention are described in greater detail below with reference to the drawing, of which:

Figure 1 is a cross-sectional view of a chipping tool designed in accordance with the invention, with cutting teeth located at its circumference and in the region of its end face,

Figure 2 is an enlarged detailed view of detail II in Figure 1, showing the design of the cutting teeth with several cutting projections, which are here pointed and project in the axial direction,

Figure 3 shows a variant of the arrangement according to Figure 1 with cutting teeth of a different shape, and

Figure 4 is an enlarged detailed view of detail IV in Figure 3, the cutting teeth having wave-shaped cutting projections projection in the axial direction.

[0013] Figure 1 is a cross-sectional view of a chipping tool 1 according to the invention for wood-type materials. The chipping tool as designed according to the invention can also be used for other materials, in particular for Nl metals, plastics, plasterboard, fibrous composite materials or the like. In the illustrated embodiment, the chipping tool 1 is provided for formatting plates, in particular chipboard, and can be driven about an axis of rotation 2 for this purpose. The chipping tool 1 comprises a substantially circular disc-shaped base body 3, along the circumference 4 of which a plurality of cutting teeth 5 is distributed, in particular evenly. The cutting teeth 5 are arranged along the circumference 4 of the base body 3 in such a way that they partially project in the axial direction predetermined by the axis of rotation 2 beyond an associated end face 14 of the base body 3. In the process of the so-called formatting of chipboard or comparable plates of a wood-type material, the chipping tool 1 is moved in a radial direction perpendicular to the axis of rotation 2 relative to the workpiece not shown in the drawing. In this process, the cutting teeth 5 machine the material of the workpiece on their circumferential side and at their end face.

[0014] Figure 2 is an enlarged detailed view of detail II in Figure 1. According to this, an individual cutting tooth 5 located at the circumference 4 of the base body 3 has a peripheral blade 6 located on the outside in the radial direction 11 and a first cutting projection 7, which projects beyond the base body 3 in the axial direction relative to the axis of rotation 2 shown in Figure 1 and adjoins the peripheral blade 6. The cutting projection 7 can be represented by a corner of the peripheral blade 6, which is here straight. In the illustrated embodiment, a chamfer 15 is provided between the radially outward cutting projection 7 and the peripheral blade 6. Instead of a straight design, the peripheral blade 6 can be curved. In the illustration of Figure 2, the peripheral blade 6 runs from left to right, i.e. slanting towards the cutting projection 7, being therefore inclined towards the axis of rotation 2 (Figure 1).

[0015] In addition to the first cutting projection 7, the cutting tooth 5 is provided with at least a second cutting projection 8 projecting beyond the base body 3 in the axial direction. In the illustrated embodiment, there is additionally provided a third cutting projection 9 radially inward of the second cutting projection 8 and projecting beyond the base body 3 in the axial direction. It may, of course, also be expedient to provide additional cutting projections located further inward relative to the radial direction 11, and a total number of two to five cutting projections 7, 8, 9 per cutting tooth 5 has been found to be expedient. Relative to the adjacent radially outward cutting projection 7, the second cutting projection 8 is set back slightly in the axial direction. The same applies to the third cutting projection 9, which is set back in the axial direction relative to the adjacent radially outward cutting projection 8. A reverse arrangement or axial offset between the cutting projections 7, 8, 9, in which the radially outward cutting projection 7, 8 is set back relative to the adjacent radially inward cutting projection 8, 9, may also be expedient, however. The cutting projections 7, 8, 9 have axially outer points 12. In addition, they or their points 12 lie on a straight line 10, which is inclined relative to the radial direction 11 by a small angle a to produce the above-described axial offset. The angle a lies preferably in a range of 0.5° to 2.0° inclusive and is 1.0° in the illustrated embodiment. As a result, The respective radially inward cutting projection 8, 9 is set back relative to the respective adjacent radially outward cutting projection 7, 8 towards the base body 3 in the axial direction.

[0016] The cutting tooth 5 is ground sharp not only in the region of its peripheral blade 6, but also at its chamfer 13 and in the whole end region covering the cutting projections 7, 8, 9. In this, a grinding contour has been chosen in which the cutting projections 7, 8, 9 are asymmetric relative to the axial direction. This means that the flanks of the cutting projections 7, 8, 9, which adjoin their respective points 12, lie radially outwards at a flatter angle to the axial direction than the radially inward legs adjoining the points. Asymmetric design of the points 12 or the cutting projections 7, 8, 9 or an asymmetric design in the reverse direction may also be expedient, however.

[0017] By way of example, Figure 2 shows one of many cutting teeth 5, all cutting teeth 5 being designed identically. As a result of arranging the cutting teeth 5 at the circumference 4 of the base body 3, the peripheral blades 6 of all cutting teeth 5 lie on a common conical surface. The same applies to the chamfers 13 and the straight lines 10 of all cutting teeth 5. An arrangement in which not all of the cutting teeth 5 are designed in the illustrated shape can also be expedient, however. It is, for example, possible that the cutting projections 7, 8, 9 of an individual cutting tooth 5 are offset in the radial direction 11 against those of a cutting tooth 5 which is adjacent in the circumferential direction, and/or that a different shape and/or number is/are provided.

[0018] Figure 3 shows a variant of the arrangement according to Figure 1, in which the cutting teeth 5 have a different shape. The detail IV of Figure 3 is shown as an enlarged detail in Figure 4, according to which the cutting projections 7, 8, 9 have a contour with a rounded wave shape. There are no sharp-edged points 12 as in Figure 2. Like in the case of the embodiment according to Figure 2, however, the cutting tooth 5 is ground sharp in the whole region covering the cutting projections 7, 8, 9 while forming the rounded wave shape. In the remaining features and reference numbers, the embodiment according to Figures 3 and 4 corresponds to that according to Figures 1 and 2.

[0019] The features of the embodiment according to Figures 1 and 2 can obviously be combined with those of the embodiment according to Figures 3 and 4. It may, for example, be expedient to combine pointed and rounded cutting projections 7, 8, 9 within an individual cutting tooth 5. It is moreover conceivable to use, within an individual chipping tool 1, different cutting teeth 5, e.g. alternating between pointed and rounded cutting projections 7, 8, 9.

Claims (8)

Use of a chip-taking tool (1) for formatting sheets, in particular of a wood-like material, wherein the chip-taking tool is intended for rotary operation about a axis of rotation (2) and comprises a base body (3), on whose perimeter (4) cutting teeth (5) are arranged, each of the cutting teeth comprising a circumferential cutting edge (6) and a cutting projection (7) which protrude relative to the axis of rotation (2) past an end surface (14) of the base body (3) in the axial direction and adjacent to the circumferential cutting insert (6), characterized in that the cutting teeth (5) radially internally of the cutting projection (7) comprise at least one other, preferably also at least one third in axial direction, in addition to the basic cutting projection (3). , 9). Use of a cutting tool according to claim 1, characterized in that the radially inner cutting protrusion (8, 9) is displaced in the axial direction relative to the radially outer cutting protrusion (7, 8) and in particular is retracted. Use of a cutting tool according to claim 2, characterized in that the cutting projections (7, 8, 9) for a single cutting tooth (5) lie on a line (10) which is perpendicular to a perpendicular to the axis of rotation (2) radial direction (11) is inclined at an angle (a), the size of which is preferably in a range from and incl. 0.5 ° to 2.0 °, and more preferably about 1.0 °. Use of a cutting tool according to any one of claims 1 to 3, characterized in that the cutting projections (7, 8, 9) comprise axially exterior tips (12). Use of a cutting tool according to claim 4, characterized in that the tips (12) are designed asymmetrical. Use of a cutting tool according to any one of claims 1 to 3, characterized in that the cutting projections (7, 8, 9) have a contour with a rounded waveform. Use of a cutting tool according to any one of claims 1 to 6, characterized in that a bevel (13) is arranged between the radially outer cutting projections (7) and the circumferential cutter (6). Use of a cutting tool according to any one of claims 1 to 7, characterized in that the circumferential cutter (6) is inclined relative to the axis of rotation (2) in the direction of the cutting projection (7).