The invention relates to the area of work pieces in which segment bores are provided, which, for example, have the function of a bearing.
When designing segmented bores, in particular half shells which serve as bearings, the qualitative features, form and bearing tolerances, diameter tolerances and surface qualities can be produced by means of grinding. The grinding of segment bores is however very cost and time intensive. High costs result thereby.
The method according to the invention and the work piece according to the invention have in contrast the advantage that a cost effective production of a segment bore having advantageous properties is facilitated. The advantage is particularly that segmented bores can be produced in all angle variants.
The qualitative features, form and bearing tolerances, diameter tolerances and surface qualities of a segmented bore can, for example, be determined by the form and bearing tolerances being less than 2 μm, the diameter tolerances being less than 20 μm and surface qualities being achieved which have a roughness (Rz value) of less than 2 μm. In contrast to a grinding process, such quality features can be cost effectively achieved by honing. The tribological properties of a surface produced by means of honing have in this case a positive effect on the sliding and lubrication properties.
It is advantageous that the work pieces are arranged relative to each other such that in a projection along the common longitudinal axis, the segment bores of the work pieces form a closed circle in a multiple superposition. A reliable guidance of the honing tool, in particular a honing mandrel, is hereby ensured. The multiple superposition can in this case be twofold or also preferably more than twofold. In so doing, the guidance of the honing tool can be further improved as needed.
It is also advantageous that the work pieces are arranged at least partially distributed along the longitudinal axis. In so doing, it is further advantageous for at least two adjacent work pieces of the work pieces arranged distributed along the longitudinal axis to be arranged around the common longitudinal axis such that the segment bores of the adjacent work pieces have a slight overlap in the projection along said common longitudinal axis. Said adjacent work pieces can especially be arranged around said common longitudinal axis such that the segment bores of said adjacent work pieces have a minimal overlap in the projection along said common longitudinal axis. In so doing, lateral forces acting on the honing tool during honing and deflections of the honing tool caused thereby are reduced. A uniform guidance of the honing mandrel in the region of the segment bores of the work pieces along said common longitudinal axis and consequently a uniform chip removal is thereby facilitated. In this way, the desired qualitative features can be advantageously achieved.
It is also advantageous that the work pieces are rigidly arranged and that a honing mandrel is gimbal-mounted; said honing mandrel being guided to hone the segment bores of the work pieces, which are arranged relative to each other, with a feed along the common longitudinal axis through the segment bores. It is however also an option for the work pieces to be gimbal-mounted in each case and for a honing mandrel to be rigidly mounted; said honing mandrel being guided to hone the segment bores of the work pieces, which are arranged relative to each other, relative to said work pieces along the common longitudinal axis through the segment bores. This facilitates advantageous configurations with regard to the tool and work piece mounting, wherein a plurality of work pieces can be simultaneously processed. Cycle times are thereby significantly reduced; however, still other combinations of tool and work piece mountings are conceivable.
In an advantageous manner, the work piece which comprises the honed segment bore serves as the bearing element, wherein the honed segment bore serves as a bearing surface. In this case, it is further advantageous for the honed segment bore to be designed as a partially cylindrical, honed segment bore. The work piece can be specifically designed as a half shell. In so doing, the bearing element can, for example, serve to receive a roller on the honed segment surface. The tribological properties of the bearing surface of the work piece produced by means of honing have in this case a positive effect on the sliding and lubrication properties.
It is therefore possible to hone bore segments in an advantageous manner. Using the method, a plurality of components is simultaneously processed, and therefore short cycle times result. The tribological properties with regard to the machining marks typical for the method have a positive effect on the sliding and/or lubrication properties.
Preferred exemplary embodiments of the invention are explained in detail in the subsequent description with reference to the attached drawings, in which corresponding elements are provided with identical reference numerals. In the drawings:
In addition, the work pieces 1 to 4 are arranged around the longitudinal axis 9 such that a projection along the common longitudinal axis 9 forms a closed circle. The direction of the projection is denoted in
The honing tool 10 is guided along the longitudinal axis 9 through the segment bores 5 to 8 of the workpieces 1 to 4. A feed direction, corresponding to the viewing direction denoted with the reference symbol II, is thereby aligned to the common longitudinal axis 9. The honing tool 10 is therefore moved along said longitudinal axis 9 in order to hone the segment bores 5 to 8. Said honing tool 10 can in this case be gimbal-mounted.
It is also an option for the honing tool 10 to be rigidly mounted while the work pieces 1 to 4 are gimbal-mounted. Other combinations of tool and work piece mounting are also possible.
An advantageous clamping of the work pieces 1 to 4 relative to each other is therefore specified, which facilitates a reliable guiding of the honing tool 10. In so doing, honed segment bores 5 to Scan be designed in the work pieces 1 to 4.
When honing the segment bore 5 of the work piece 1 together with the segment bores 6, 7, 8 of the work pieces 2, 3, 4, typical machining marks arise on the segment bore 5 and also on the other segment bores 6 to 8. Said machining marks which are typical of the method and which occur on the honed segment bore 5 have a positive effect on the sliding and lubrication properties.
In this exemplary embodiment, The work piece 1 comprises a honed segment bore 5, which extends over a segment 11 of more than 180°. The work piece 1 can also comprise a segment bore 5 in the form of a half-shell bore, wherein the segment 11 then extends at least approximately around 180°. Other embodiments are also possible. The segment 11 of the segment bore 5 can, for example, also be less than 180°. Depending on the size of the segment 11 of the individual work pieces 1 to 4, a certain minimum number of work pieces which are required to form a closed circle 12 results. It is however preferable for a greater number of work pieces to be arranged in order to achieve a multiple superposition in the configuration the closed circle 12. On the one hand, an advantageous guidance of the honing tool 10 is thereby achieved; and on the other hand, a greater number of work pieces can be processed simultaneously, thus reducing the cycle time.
The invention is not limited to the exemplary embodiments which have been described.
Number | Date | Country | Kind |
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10 2009 054 946.3 | Dec 2009 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2010/066061 | 10/25/2010 | WO | 00 | 9/4/2012 |