Machining tool, processing device and method for processing workpieces

Abstract

The invention relates to a machining tool (2) for processing a bore in a workpiece, in particular for simultaneous processing of a plurality of bores distanced from one another by a predefined distance, said machining tool having a cutting body (8) extending in the direction of a tool longitudinal axis (4) and having at least one cutting element (12) arranged circumferentially, and a guide body (10), which adjoins the cutting body (8) in the direction of the tool longitudinal axis (4), is fastened to the cutting body (8) and has at least one circumferentially arranged guide element (20). The guide body (10) is free of cutting elements (12) and the guide body (10) is designed to exert a preload force such that, during use, the at least one guide element (20) is preloaded against a bearing for the guide body (10).

Claims

1. A machining tool for processing a bore of a workpiece comprising a cutting body extending in the direction of a tool longitudinal axis and having at least one circumferentially arranged cutting element, characterized by a guide body, which adjoins the cutting body in the direction of the tool longitudinal axis, is fastened to the cutting body and has at least one circumferentially arranged guide element, wherein the guide body is free of cutting elements and wherein the guide body is configured to exert a preload force such that, during use, the at least one guide element is preloaded against a bearing for the guide body.

2. The machining tool according to claim 1, characterized in that the guide body comprises a body longitudinal axis which, during use, is arranged offset to the tool longitudinal axis.

3. The machining tool according to claim 2, characterized in that the guide body can be displaced radially relative to the tool longitudinal axis by means of an adjusting mechanism.

4. The machining tool according to claim 3, characterized in that the body longitudinal axis is aligned parallel to the tool longitudinal axis and that, in order to realize a degree of freedom, the adjusting mechanism is configured such that the body longitudinal axis can be displaced in radial direction relative to the tool longitudinal axis.

5. The machining tool according to claim 3, characterized in that the guide body comprises two guide elements which are circumferentially arranged at two angle positions, wherein an angle bisector is assigned to the two angle positions, and that the preload force extends in the direction of the angle bisector.

6. The machining tool according to claim 3, characterized in that the adjusting mechanism comprises a guide rail or guide groove, which extends in radial direction and along which the guide body can be displaced.

7. The machining tool according to claim 3, characterized in that, in order to realize a degree of freedom, the adjusting mechanism is configured such that the guide body can be rotated about the body longitudinal axis.

8. The machining tool according to claim 3, characterized in that, in order to realize a degree of freedom, the adjusting mechanism is configured such that the body longitudinal axis can be tilted relative to the tool longitudinal axis.

9. The machining tool according to claim 1, characterized in that during use, the mass of the guide body is distributed unevenly around the tool longitudinal axis in order to constructively specify a directed imbalance during rotation around the tool longitudinal axis, whereby in particular the distribution of the mass of the guide body around the tool longitudinal axis deviates from the distribution of the mass of the cutting body around the tool longitudinal axis.

10. The machining tool according to claim 1, characterized in that, during use, during rotation around the tool longitudinal axis, the at least one cutting element is guided along a cutting circle having a cutting radius, and that, during rotation around the tool longitudinal axis, the at least one guide element is guided along a guide circle having a guide radius, wherein the guide radius is greater than or equal to the cutting radius.

11. The machining tool according to claim 1, characterized in that the cutting body circumferentially comprises a plurality of cutting elements which, viewed in the direction of the tool longitudinal axis, are arranged in a line.

12. The machining tool according to claim 1, characterized in that, viewed in the direction of the tool longitudinal axis, a shaft adjoins the cutting body opposite to the guide body.

13. A processing device for processing workpieces comprising a machine tool having a spindle without an alignment mechanism, characterized by a machining tool according to claim 1, wherein the machining tool is directly connected to the spindle.

14. A method for processing workpieces by means of a processing device comprising a machine tool having a spindle and comprising a machining tool according to claim 1, wherein a preload force is generated with the aid of the guide body during use.

Description

DESCRIPTION OF THE FIGURES

[0034] In simplified, schematized illustrations, the figures respectively show:

[0035] FIG. 1 a machining tool having a cutting body and a guide body in a first perspective view,

[0036] FIG. 2 the machining tool having the cutting body and the guide body in a second perspective view,

[0037] FIG. 3 the machining tool having the cutting body and the guide body in the second perspective view, wherein the guide body is displaced relative to the cutting body,

[0038] FIG. 4 the machining tool having the cutting body and without the guide body in the second perspective view,

[0039] FIG. 5 the guide body in a third perspective view and

[0040] FIG. 6 the guide body in a fourth perspective view.

[0041] Parts having the same effect are provided with the same reference signs in the figures.

DESCRIPTION OF THE DESIGN EXAMPLE

[0042] A machining tool 2, which is described below as an example and shown in FIG. 1, is used for simultaneously processing a plurality of bores which are spaced apart from one another by a predefined distance and is accordingly adapted to this intended application.

[0043] The machining tool 2 is extended along a tool longitudinal axis 4, wherein this tool longitudinal axis 4 represents a type of central longitudinal axis of the machining tool 2. The machining tool 2 further comprises a shaft 6, which can be inserted into a complementary tool holder of a spindle of a not depicted machine tool, and can thus be connected to the machine tool in a reversibly detachable manner. For processing workpieces, the shaft 6 of the machining tool 2 is then accordingly inserted into the tool holder of the machine tool and thus connected to the machine tool. The machining tool 2 is subsequently set in rotation with the aid of the spindle of the machine tool, whereby the axis of rotation coincides at least in good approximation with the tool longitudinal axis 4.

[0044] An exact coincidence is intended here, but this cannot always be realized because of the given manufacturing tolerances. The spindle nonetheless preferably has no alignment mechanism, and the machining tool is still preferably connected directly with the spindle without the interposition of an alignment adapter. The shaft 6 also preferably does not have an alignment mechanism and is further preferably configured in one piece or monolithically.

[0045] Viewed in the direction of the tool longitudinal axis 4, the shaft 6 is adjoined by a cutting body 8, which in the design example has a cylindrical shape and is non-detachably connected to the shaft 6. It can therefore not be detached from the shaft 6 in a non-destructive manner. On the end of the cutting body 8 opposite to the shaft 6, a guide body 10 is positioned, which during use of the machining tool 2 quasi forms the free end of the machining tool 2 and is preferably connected to the cutting body 8 in a reversibly detachable manner.

[0046] In the design example, three cutting elements 12 are arranged circumferentially on the cutting body 8, whereby each cutting element 12 is fastened in a reversibly detachable manner by means of a screw 14 to the cutting body 8, or rather to a cutting element carrier which also forms the cutting body 8. The cutting elements 12 can thus be replaced as needed. The screws 14 used for fastening the cutting elements 12 are expediently disposed in a depression 16 and, in the design example, the cutting elements 12 are arranged along a line 18 along the tool longitudinal axis 4, whereby the line 18 extends parallel to the tool longitudinal axis 4. The distance between the cutting elements 12 corresponds to the distance between the bores to be processed on the workpieces for which the machining tool 2 is designed.

[0047] In the design example, the guide body 10 likewise has a cylindrical shape. Two guide gibs 20 are positioned on the circumference of the guide body 10 as guide elements, whereby the guide rails 20 are arranged parallel to a body longitudinal axis 22 of the guide body 10. The body longitudinal axis 22 of the guide body 10 corresponds to a type of central longitudinal axis of the guide body 10, which also substantially coincides with the center of mass axis of the guide body 10 and thus runs through the center of mass of the guide body 10.

[0048] In the design example, the guide body 10 is not only connected to the cutting body 8 in a reversibly detachable manner, but also via an adjusting mechanism 24, which, as indicated in FIG. 4 and FIG. 5, comprises a rail 26 and a groove 28. The rail 26 is formed on the guide body 10, and the groove 28 is formed on the cutting body 8. This adjusting mechanism 24 allows the body longitudinal axis 22 and thus the guide body 10 to be displaced in a radial direction relative to the tool longitudinal axis 4 and thus to the cutting body 8. The respective displacement position is fixed by means of a not depicted screw, for example, or is variably specified or set by the rotational position of a screw. In an initial position or starting position, the guide body 10 is typically arranged such that the body longitudinal axis 22 of the guide body 10 coincides with the tool longitudinal axis 4.

[0049] However, for use of the machining tool 2, i.e. for processing a workpiece, the body longitudinal axis 22 of the guide body 10 is moved out of this starting position, so that the body longitudinal axis 22 and the tool longitudinal axis 4, and thus typically the axis of rotation of the machining tool 2, are disposed offset parallel to one another. The machining tool 2 is preloaded by means of a corresponding offset in order to achieve a secure guidance of the machining tool 2 on a bearing provided for this purpose, or in a bearing bore provided for this purpose, which has a beneficial effect on the processing precision.

[0050] Then, once the respective machining tool 2 is preloaded, the guide gibs 20 of the guide body 10 rest against a wall of the bearing or bearing bore with an intended and correspondingly predetermined contact pressure, as a result of which the preloading of the machining tool 2 is achieved. The direction of this contact pressure in the design example is specified by a preloading direction 30, which coincides in good approximation with a contact pressure angle bisector 32 that is determined by the two angle positions 34 of the two guide gibs 20.