EP2712702B1 - Belt finishing device, belt finishing system and method for producing a belt finishing device - Google Patents

Description

The invention relates to a belt finishing device, comprising a pressing device for pressing a finishing strip against a workpiece surface, wherein the pressing device comprises a pressing belt, which is mounted on two spaced in the running direction of the finishing tape arranged bearing surfaces.

From the EP 2 212 058 B1 is a device for finishing peripheral surfaces on cylindrical workpiece sections known. This device comprises a flexurally elastic pressure band for pressing a finishing tape on peripheral surfaces of substantially cylindrical workpiece sections.

During finish machining, the workpiece surface to be machined is driven in rotation and this rotational movement is superimposed by a relative movement directed parallel to the workpiece axis between the workpiece and the finishing belt. As a result, the workpiece surface is provided with a characteristic for the finishing process cross-cut structure.

The workpiece surfaces to be machined are, in particular, bearing surfaces of crankshafts or camshafts. These storage areas must be manufactured with a high dimensional accuracy. In particular, the bearing surfaces of the crankshafts or camshafts should be made so that they ensure in conjunction with the bearing surfaces of a crankcase or camshaft housing or with the bearing surfaces of a connecting rod possible backlash-free and low-friction bearings with high wing fractions.

It has been found that with the known Bandfinishvorrichtungen the above requirements are not optimally fulfilled. On this basis, the present invention has the object to provide a belt finishing device, which allows the production of particularly dimensionally stable workpiece surfaces.

This object is achieved in that at least one of the bearing surfaces and / or the pressure belt has a profile that deviates in the width direction of the finishing belt of a straight-line course.

According to the invention, the following has been recognized: when using bearing surfaces known from the prior art, which in the width directions of the finishing strip a straight-line profile have (that is, for example, when using cylindrical bearing rollers and a profile in the rectangular Andrückbands), the pressure band is seen in the width direction of the finishing tape exposed to different tensile stresses. In a region with a higher tensile stress of the pressure belt, a region of the finishing belt adjacent to this region is subjected to a higher pressure force. In regions of the lower tensile pressure belt, lower-pressure regions supported on these regions are subjected to a lower pressure force. The different pressing forces cause the workpiece surface to be machined to deviate from a desired nominal contour.

According to the invention, the geometry of the workpiece surface to be machined can now be influenced, namely by designing the profile of at least one of the bearing surfaces and / or the pressure belt deviating from a rectilinear course. A profile deviating from a rectilinear profile according to the invention has a predetermined shape which can not be provided by the surfaces of cylindrical bearing rollers with normal tolerances and by the pressure belts of rectangular cross section.

The profile according to the invention of the at least one bearing surface and / or the pressure belt preferably has at least one profile section which deviates from a mathematically ideal straight line by at least 10 micrometers, in particular by at least 20 micrometers.

In particular, it is preferred that the profile is curved. For example, the profile of the Andrückbands is curved. By the plant of curved in the profile Andrückbands to the finishing tape and the finishing tape in curved accordingly, namely about a direction parallel to the running direction of the finishing strip axis of curvature. In this way, the geometry of the workpiece surface to be punched can be influenced in a targeted manner. For example, the curvature of the pressure belt can be designed such that the workpiece surface to be finished receives an approximately ideal cylindrical shape. But it is also possible to interpret the curvature of the Andrückbands so that a workpiece surface is produced, the desired shape deviates from a cylindrical shape. In particular, convex workpiece surfaces can be produced. But it is also the production of concave curved workpiece surfaces possible.

It is also possible that at least one of the bearing surfaces in the width direction of the finishing strip deviates from a straight course. For example, the profile of at least one of the bearing surfaces is curved. For example, if at least one of the bearing surfaces is concavely curved, the pressure band is applied in outer side regions with a higher voltage than in a central region. As a result, a finishing belt resting against this pressing belt is subjected to a higher pressing force in outer side areas than in a central area. In this way, a workpiece surface can be produced which is convex in profile, that is in a central region has a larger diameter than in outer side regions.

It is also possible to combine both of the possibilities described above (at least one curved bearing surface, curved pressure band in profile).

In the context of the invention, it is preferable that a bearing surface for supporting the Andrückbands is consistently made of the same material to specify particularly dimensionally stable, deviating from a straight line profile and produce.

In a corresponding manner, it is preferred that the pressure belt has a contact surface cooperating with the finishing belt, which is formed by only a single layer or pressing belt material. This allows the specification and production of a particularly dimensionally stable, deviating from a straight line profile of the Andrückbands.

According to the invention, it is possible for the at least one bearing surface and / or the pressure belt to be continuous, so that they completely support the finishing belt over its width. But it is also possible that the at least one bearing surface and / or the pressure belt has at least one interruption, so that the finishing belt is seen in the width direction, at least in the area of the interruption of the bearing surface and / or the Andrückbands acted upon with a lower pressing force. This allows a targeted influencing of the geometry of the workpiece surface in such a way that less material is removed in a rotation plane of the workpiece surface associated with the interruption of the bearing surface and / or the pressure belt than in a laterally adjacent region.

The interruptions may be, for example, pocket-shaped recesses and / or openings of at least one of the bearing surfaces and / or the pressure belt.

For example, at least one bearing surface may have recesses or grooves running parallel to the running direction of the finishing strip. It is also possible that the bearing surface is formed by a plurality of mutually separate bearing body, wherein the bearing bodies are arranged offset to one another in the width direction of the finishing tape.

The pressure belt can, for example, have pocket-shaped recesses in the region of the profile deviating from a straight-line profile, so that a pressing surface facing the finishing belt is interrupted, but a rear side of the pressure belt facing away from the finishing belt is closed. It is also possible to break the Andrückband so that the Andrückband is interrupted not only on the back of the finishing tape adjacent the front of the Andrückbands, but also in the region of the back of the belt facing away from the Andrückbands.

In a preferred embodiment it is provided that at least one of the bearing surfaces is formed by a bearing roller. This allows a storage of Andrückbands over a high wrap angle.

A further advantageous embodiment of the invention provides that the bearing roller is mounted floating. This has the advantage that the course of the Andrückbands and thus the course of the finishing tape is easily adaptable to workpiece surfaces with different diameters.

It is also preferred if the bearing roller can be supported on a stationary bearing roller support device. This allows limitation of a degree of freedom of movement of a bearing roller.

It is also possible that at least one of the bearing surfaces is formed by a stationary bearing element. Such a bearing element has a non-movable bearing surface. This allows a storage of Andrückbands with very low position tolerances.

It is possible that the pressing belt is movable relative to the bearing surfaces. However, it may be preferred if a fixing device for fixing the Andrückbands is provided relative to the bearing surfaces. In this way, a further improvement of the dimensional accuracy of the workpiece surface to be produced can be achieved.

It is conceivable to provide a pressure belt whose rear side facing away from the finishing belt has a profile which deviates from a rectilinear course. However, it is preferred if at least the pressing surface of the Andrückbands has a profile that deviates from a straight-line course. In particular, only the pressing surface of the Andrückbands has a profile that deviates from a straight-line course.

A simpler control of the transferable in the width direction of the finishing tape by means of Andrückbands on the finishing belt pressing forces arises when the pressure belt is formed in the form of an endless belt. Such a pressure belt has a front operative portion, whose front side cooperates with the back of the finishing tape. Such an endless belt is deflected in the region of the mutually spaced bearing surfaces and merges into a rear portion, which is arranged spaced from the finishing belt.

It is preferred if a rear portion of the Andrückbands is supported or supported by means of a Andrückband-supporting device. As a result, a further possibility is created to influence the tension of the pressure belt along the width of the finishing belt.

The invention further relates to a belt finishing system comprising a belt finishing device described above and a workpiece having a workpiece surface to be finish-machined.

According to the invention, at least one of the bearing surfaces and / or the pressure belt at least one interruption, wherein the workpiece surface is interrupted in the region of a bore and wherein the position of the interruption in the width direction of the finishing tape is matched to the position of the bore. Crankshafts or camshafts which have a bore, in particular an oil outlet bore, in the area of the bearing surface can be produced with such a band finishing system. A rotation plane associated with such a bore is subjected to lower pressure forces during finishing machining of the workpiece surface, so that the finishing belt presses against the workpiece in the region of the boundary of the bore with a lower force than in laterally adjacent regions. In this way, too deep penetration of the finishing tape into the bore and thus excessive material removal in the region of the bore of the bore can be prevented. This has the advantage that a workpiece section which is in any case mechanically weakened in the region of the bore is not further weakened and that, in spite of such a bore, bearing surfaces with a comparatively high aerofoil proportion can be created.

• mindestens eine der Lagerflächen oder eine dem Finishband zugewandte Andrückfläche des Andrückbands wird mit einem Profil versehen, das zu der Soll-Kontur identisch ist oder eine stärkere Ausprägung aufweist;
• mindestens eine der Lagerflächen und eine dem Finishband zugewandte Andrückfläche des Andrückbands wird jeweils mit einem Teilprofil versehen, wobei eine Überlagerung beider Teilprofile zu der Soll-Kontur identisch ist oder eine stärkere Ausprägung aufweist;
• es werden Soll-Kontur-Abschnitte definiert und für jeden der Soll-Kontur-Abschnitte ein von einer Kreiszylinderform abweichender Werkstück-Materialabtrag ermittelt; mindestens eine der Lagerflächen und/oder das Andrückband wird mit mindestens einer Unterbrechung versehen, wobei die Unterbrechung einem Soll-Kontur-Abschnitt zugeordnet wird, dessen Werkstück-Materialabtrag kleiner ist als der Werkstück-Materialabtrag eines benachbarten Soll-Kontur-Abschnitts;
• es werden Soll-Kontur-Abschnitte definiert und für jeden der Soll-Kontur-Abschnitte ein von einer Kreiszylinderform abweichender Werkstück-Materialabtrag ermittelt; mindestens eine der Lagerflächen und/oder das Andrückband wird mit Unterbrechungen versehen, welche jeweils einem Soll-Kontur-Abschnitt zugeordnet sind, wobei die Unterbrechungen in Laufrichtung des Finishbands gemessene, unterschiedliche Längen aufweisen und Unterbrechungen mit kleineren Längen Soll-Kontur-Abschnitten mit höheren Materialabtragsraten und Unterbrechungen mit größeren Längen Soll-Kontur-Abschnitten mit niedrigeren Materialabtragsraten zugeordnet werden.

The invention also relates to a method for producing a belt finishing device described above, in which the desired contour of a finished workpiece surface is determined and in addition at least one of the following measures is carried out:

• at least one of the bearing surfaces or a pressure surface of the Andrückbands facing the finishing belt is provided with a profile which is identical to the desired contour or has a stronger characteristic;
• at least one of the bearing surfaces and a pressure surface of the Andrückbands facing the finishing belt is in each case provided with a partial profile, with an overlapping of the two partial profiles being identical to the desired contour or having a stronger characteristic;
• Target contour sections are defined and a workpiece material removal deviating from a circular cylinder shape is determined for each of the target contour sections; at least one of the bearing surfaces and / or the pressure belt is provided with at least one interruption, wherein the interruption is assigned to a desired contour section whose workpiece material removal is smaller than the workpiece material removal of an adjacent target contour section;
• Target contour sections are defined and a workpiece material removal deviating from a circular cylinder shape is determined for each of the target contour sections; At least one of the bearing surfaces and / or the pressure belt is provided with interruptions, each one Target discontinuity sections are assigned, with the interruptions in the running direction of the finishing tape measured, different lengths and interruptions with smaller lengths Soll contour sections with higher material removal rates and interruptions with longer lengths Soll contour sections with lower material removal rates are assigned.

It is preferred in particular that the profile and / or the superimposition of the two partial profiles has a stronger characteristic than the desired contour, and that the profile and / or the superimposition of both partial profiles over a working width of the finishing strip defines a circular section whose segment height is about one Factor of 1.5 to 25, preferably from 3 to 15, in particular from 5 to 10, is greater than a segment height of a circular section, which is limited over the effective width of the finishing strip of the desired contour.

Advantages and embodiments of the inventive method and further features and advantages of the invention are the subject of the following description and the drawings of preferred embodiments.

Figur 1

eine Seitenansicht einer Ausführungsform einer Bandfinishvorrichtung;

Figur 2

eine Seitenansicht eines Teils der Bandfinishvorrichtung gemäß Fig. 1 in vergrößerter Darstellung, wobei ein erstes Werkstück mit einem ersten Durchmesser dargestellt ist;

Figur 3

eine der Fig. 2 entsprechende Ansicht, wobei ein zweites Werkstück mit einem im Vergleich zu dem ersten Durchmesser kleineren zweiten Durchmesser dargestellt ist;

Figur 4

eine Ansicht längs einer in Fig. 2 mit IV - IV bezeichneten Schnittlinie;

Figur 5

eine Ansicht längs einer in Fig. 2 mit V - V bezeichneten Schnittlinie;

Figur 6

einen in Fig. 5 mit VI bezeichneten Ausschnitt in vergrößerter Darstellung;

Figur 7

eine der Fig. 4 entsprechende Ansicht einer weiteren Ausführungsform;

Figur 8

eine der Fig. 5 entsprechende Ansicht der Ausführungsform gemäß Fig. 7;

Figur 9

eine der Fig. 6 entsprechende Ansicht der Ausführungsform gemäß Fig. 7;

Figur 10a bis 10c

der Fig. 9 entsprechende Ansichten in aufeinander folgenden Werkstückbearbeitungsphasen;

Figur 11a bis 11c

jeweils mit den aufeinander folgenden Werkstückbearbeitungsphasen gemäß Fig. 10 bis 10c korrespondierende Kräfteverläufe;

Figur 12

eine Seitenansicht einer weiteren Ausführungsform einer Bandfinishvorrichtung, wobei ein erstes Werkstück mit einem ersten Durchmesser dargestellt ist;

Figur 13

eine der Fig. 12 entsprechende Ansicht, wobei ein zweites Werkstück mit einem im Vergleich zu dem ersten Durchmesser kleineren zweiten Durchmesser dargestellt ist;

Figur 14

eine Ansicht längs einer in Fig. 12 mit XIV - XIV bezeichneten Schnittlinie;

Figur 15

einen in Fig. 14 mit XV bezeichneten Ausschnitt in vergrößerter Darstellung;

Figur 16

eine perspektivische Ansicht einer Ausführungsform eines Lagerelements zur Verwendung bei der Bandfinishvorrichtung gemäß Fig. 12;

Figur 17

eine Seitenansicht des Lagerelements gemäß Fig. 16;

Figur 18

eine Draufsicht des Lagerelements gemäß Fig. 16;

Figur 19

eine der Fig. 17 entsprechende Ansicht bei Verwendung eines Andrückbands, welches ein gekrümmtes Profil aufweist;

Figur 20

eine Vorderansicht der Anordnung gemäß Fig. 19;

Figur 21

eine Ansicht der Anordnung gemäß Fig. 19 längs einer in Fig. 19 mit XXI - XXI bezeichneten Schnittlinie;

Figur 22

eine perspektivische Ansicht einer weiteren Ausführungsform eines Lagerelements zur Verwendung bei der Bandfinishvorrichtung gemäß Fig. 12;

Figur 23

eine Seitenansicht des Lagerelements gemäß Fig. 22;

Figur 24

eine Draufsicht des Lagerelements gemäß Fig. 22;

Figur 25

eine der Fig. 23 entsprechende Ansicht bei Verwendung eines Andrückbands, welches in einem unmontierten Zustand ein geradliniges Profil aufweist;

Figur 26

eine Vorderansicht der Anordnung gemäß Fig. 25;

Figur 27

eine Ansicht der Anordnung gemäß Fig. 25 längs einer in Fig. 25 mit XXVII - XXVII bezeichneten Schnittlinie;

Figur 28

eine Seitenansicht einer weiteren Ausführungsform einer Anordnung mit einem Lagerelement und einem Andrückband;

Figur 29

eine Vorderansicht der Anordnung gemäß Fig. 28;

Figur 30

eine Ansicht der Anordnung gemäß Fig. 28 längs einer in Fig. 28 mit XXX - XXX bezeichneten Schnittlinie;

Figur 31

eine Seitenansicht einer weiteren Ausführungsform einer Anordnung mit einem Lagerelement und einem Andrückband;

Figur 32

eine Vorderansicht der Anordnung gemäß Fig. 31;

Figur 33

eine Ansicht der Anordnung gemäß Fig. 31 längs einer in Fig. 31 mit XXXIII - XXXIII bezeichneten Schnittlinie;

Figur 34

eine schematische Ansicht eines Beispiels für eine Soll-Kontur einer Werkstückoberfläche;

Figur 35

eine Vorderansicht einer Ausführungsform eines Andrückbands zur Herstellung einer Soll-Kontur gemäß Fig. 34;

Figur 36

eine schematische Ansicht eines weiteren Beispiels für eine Soll-Kontur einer Werkstückoberfläche; und

Figur 37

eine Vorderansicht einer Ausführungsform eines Andrückbands zur Herstellung einer Soll-Kontur gemäß Fig. 36.

In the drawing show:

FIG. 1

a side view of an embodiment of a belt finishing device;

FIG. 2

a side view of a portion of the belt finishing device according to Fig. 1 in an enlarged view, wherein a first Workpiece is shown with a first diameter;

FIG. 3

one of the Fig. 2 corresponding view, wherein a second workpiece is shown with a smaller compared to the first diameter second diameter;

FIG. 4

a view along an in Fig. 2 with IV - IV designated section line;

FIG. 5

a view along an in Fig. 2 with V - V designated cutting line;

FIG. 6

one in Fig. 5 with VI designated section in an enlarged view;

FIG. 7

one of the Fig. 4 corresponding view of another embodiment;

FIG. 8

one of the Fig. 5 corresponding view of the embodiment according to Fig. 7 ;

FIG. 9

one of the Fig. 6 corresponding view of the embodiment according to Fig. 7 ;

FIGS. 10a to 10c

of the Fig. 9 corresponding views in successive workpiece machining phases;

FIGS. 11a to 11c

in each case with the successive workpiece machining phases according to Fig. 10 to 10c corresponding courses of forces;

FIG. 12

a side view of another embodiment of a belt finishing device, wherein a first workpiece is shown with a first diameter;

FIG. 13

one of the Fig. 12 corresponding view, wherein a second workpiece is shown with a smaller compared to the first diameter second diameter;

FIG. 14

a view along an in Fig. 12 Section XIV - XIV;

FIG. 15

one in Fig. 14 with XV designated section in an enlarged view;

FIG. 16

a perspective view of an embodiment of a bearing element for use in the belt finishing according to Fig. 12 ;

FIG. 17

a side view of the bearing element according to Fig. 16 ;

FIG. 18

a plan view of the bearing element according to Fig. 16 ;

FIG. 19

one of the Fig. 17 corresponding view when using a Andrückbands having a curved profile;

FIG. 20

a front view of the arrangement according to Fig. 19 ;

FIG. 21

a view of the arrangement according to Fig. 19 along a in Fig. 19 with XXI - XXI cutting line;

FIG. 22

a perspective view of another embodiment of a bearing element for use in the belt finishing according to Fig. 12 ;

FIG. 23

a side view of the bearing element according to Fig. 22 ;

FIG. 24

a plan view of the bearing element according to Fig. 22 ;

FIG. 25

one of the Fig. 23 corresponding view when using a Andrückbands, which has a straight profile in an unmounted state;

FIG. 26

a front view of the arrangement according to Fig. 25 ;

FIG. 27

a view of the arrangement according to Fig. 25 along a in Fig. 25 with XXVII - XXVII designated section line;

FIG. 28

a side view of another embodiment of an arrangement with a bearing element and a pressure belt;

FIG. 29

a front view of the arrangement according to Fig. 28 ;

FIG. 30

a view of the arrangement according to Fig. 28 along a in Fig. 28 with XXX - XXX designated cutting line;

FIG. 31

a side view of another embodiment of an arrangement with a bearing element and a pressure belt;

FIG. 32

a front view of the arrangement according to Fig. 31 ;

FIG. 33

a view of the arrangement according to Fig. 31 along a in Fig. 31 section line marked XXXIII - XXXIII;

FIG. 34

a schematic view of an example of a desired contour of a workpiece surface;

FIG. 35

a front view of an embodiment of a Andrückbands for producing a desired contour according to Fig. 34 ;

FIG. 36

a schematic view of another example of a desired contour of a workpiece surface; and

FIG. 37

a front view of an embodiment of a Andrückbands for producing a desired contour according to Fig. 36 ,

One embodiment of a belt finishing device is shown in FIG FIG. 1 generally designated by the reference numeral 10. This is used for finishing machining of a particular rotationally symmetrical workpiece surface 12 of a workpiece 14. The finishing machining of the workpiece surface 12 is effected by means of a finishing tape 16.

For example, a supply 17 is provided for the finishing belt 16. Starting from the supply 17, the finishing belt is guided and deflected on a guiding / deflecting device 18 and lies in an operative region 20 within a Wrap angle (which is, for example, at least about 10 °) at the workpiece surface 12 at.

The area of action 20 is adjoined by an area 22 in which used finishing belt 16 is collected. Alternatively, the finishing belt 16 is deflected in the region 22 and fed to a first active region 20 opposite the second effective region 24. Also in the second active region 24, the finishing tape lies against the workpiece surface 12 within a wrapping angle (which, for example, is at least approximately 10 °).

A guiding / deflecting device 26 adjoins the active region 24, from which the finishing belt 16 is fed to a collecting region 28.

For pressing the finishing strip 16 in the effective regions 20 and / or 24, in each case an effective region 20, 24 associated pressing devices 30 are provided. The pressure devices 30 are respectively held on holders 32, which are preferably pivotable about respectively associated pivot axes 34.

During finishing machining of the workpiece 14, it is driven in rotation about a workpiece axis 36 (see FIG Fig. 2 ). This rotational movement is superimposed on a parallel to the axis of rotation 36, oscillating relative movement between the finishing belt 16 and the workpiece 14.

FIG. 2 shows an enlarged view of a pressing device 30. This includes two spaced bearing rollers 38, the radially outward facing surfaces bearing surfaces 40 for storing a Andrückbands 42 have.

The pressure belt 42 is formed in the form of an endless belt. With a front portion 44, the pressure belt 42 cooperates with the finishing belt 16. At the front portion 44 close to the bearing surfaces 40 cooperating deflection sections 46, which merge into a rear portion 48 of the Andrückbands 42. The rear portion 48 is spaced from the front portion 42. The rear portion 48 is supported by a Andrückband-supporting device 50 in the region of a support surface 52. The support surface 52 acts on the rear portion 48 of the Andrückbands 42 with a force acting in the direction of the workpiece 14 supporting force.

The bearing rollers 38 have mutually parallel bearing axes 54. The bearing axes 54 are floating, for example by means of bearing elements 58 in the form of scenes. The shape and arrangement of the bearing elements 58 (for example, the extension direction of the scenes) is such that the bearing axes 54 are movable in the radial direction to the workpiece axis 36.

Preferably, the bearing rollers 38 are supported by a stationary bearing roller support 60. The device 60 includes, for example, a support surface 62, by means of which the bearing rollers 38 are supported with the interposition of the Andrückbands 42. The devices 50 and 60 may be formed integrally with each other. The support surfaces 52 and 62 preferably merge continuously (kink-free) into each other.

The pressing device 30 is suitable for workpieces 14 with different diameters. For example, if instead of the workpiece 14 (see FIG. 2 ) a workpiece 14 'of smaller diameter (see FIG. 3 At the same time, the wrap angle of the active region 24 increases. Moreover, the bearing shafts 54 of the bearing rollers 38 continue to shift in the direction of the workpiece 14 '.

The bearing rollers 38 are based on the bearing axes 54 rotationally symmetrical and have in profile convex curved bearing surfaces 40 (see FIG. 4 ). The bearing surface 40 serves to support a rear side 64 (cf. FIG. 6 ) of the Andrückbands 42.

The pressure belt 42 has a pressing surface 66 facing away from the rear side 64, which acts on a rear side 68 of the finishing belt 16 with pressing forces, so that an active surface 70 of the finishing belt 16 provided with finish material is pressed against the workpiece surface 12 of the workpiece 14 to be finish-machined.

The pressing belt 42 is rectangular in cross-section in an undeformed initial state. Thus, the pressing surface 66 in the undeformed initial state of Andrückbands 42 on a straight line. The pressure belt 42 is elastically deformable and lies in the deflection sections 46 (see FIG FIG. 2 ) with its back 64 flat on the bearing surface 40 at. As a result, the pressing belt 42 deforms, so that the pressing surface 66 has a curved profile corresponding to the curvature of the bearing surface 40. The curvature of the pressing surface 66 of the Andrückbands 42 accordingly deforms the on the pressure belt 42 fitting finishing belt 16 so that the active surface 70 of the finishing belt 16 convexly curved and a concave workpiece surface 12 can be produced. The bearing surfaces 40 and the pressure surface 66 of the Andrückbands 42 thus have a curved profile which deviates in the width direction 72 of the finishing belt 16 from a straight-line course.

The above description applies accordingly to one in the FIGS. 7 to 9 illustrated embodiment. In this embodiment, however, the bearing surfaces 40 of the bearing rollers 38 are concavely curved. With the interposition of Andrückbands 42 creates a concave curved active surface 70 of the finishing belt 16, whereby a convexly curved workpiece surface 12 of the workpiece 14 can be produced.

Preferably, a radius of curvature of a convexly curved bearing surface 40 (cf. Fig. 4 ) between about 1000 mm and about 6000 mm. With a bearing width of about 20 to 25 mm, a chord height (ie a maximum, based on a circular cylinder shape overshoot) of about 0.02 to 0.05 mm is suitable.

A radius of curvature of a concavely curved bearing surface 40 (cf. Fig. 7 ) is preferably between about 1000 mm and about 6000 mm. With a bearing width of approx. 20 to 25 mm, a chord height (ie a maximum reduction based on a circular cylinder shape) of approx. 0.02 to 0.05 mm is suitable.

FIG. 10c shows one of the FIG. 9 corresponding representation. According to the state FIG. 10c Previous workpiece processing phases are in the Figures 10a and 10b shown.

In the in FIG. 10a As shown, the workpiece surface 12 of the workpiece 14 is cylindrical. As a result of the curvature of the active surface 70 of the finishing strip 16, this is initially present only with edge regions 74 at corresponding edge regions 76 of the workpiece 14. These areas exert correspondingly high opposing forces 78 (cf. FIG. 11a ) on the finishing belt 16. As the workpiece surface 12 progresses, the counterforces 78 continue to distribute toward a central region 80 (see FIG FIG. 11b ) of the workpiece 14.

In FIG. 11c a state is shown in which the workpiece surface 12 assumes a curved target contour. In this state, the concave radius of curvature of the active surface 70 of the finishing tape 16 corresponds to the convex radius of curvature of the workpiece surface 12 of the workpiece 14 and the active surface 70 is located in the width direction 72 on the entire surface of the workpiece surface 12 of the workpiece 14.

For the following with reference to the FIGS. 12 to 27 described pressing means 30 is made to the above description of the pressing means 30 according to FIGS. 1 to 11c Referenced. In particular, the differences to the above-described pressing devices 30 will be discussed below.

In the pressing device 30 according to Figures 12 and 13 instead of the bearing rollers 38, a stationary bearing element 82 with immovable bearing surfaces 40 is provided.

Such bearing elements 82 are for example in Figures 16 and 22 shown in perspective. The bearing elements 82 have in the area between two spaced apart Bearing surfaces 40 a the effective range 20 of the finishing belt 16 associated constriction 84. The constriction 84 is so large that a front portion 44 of the pressure belt 42 arranged at the level of the effective portion 20 of the finishing belt 16 is spaced apart from the bearing element 82 by its rear side 64 and a free space 86 is created (see FIG Figures 12 and 13 ). The clearance 86 forms an escape space for the front portion 44 of the Andrückbands 42 upon application of a partial circumference of a workpiece surface to be finished 12 of a workpiece 14. Depending on the size of the workpiece 14 and the diameter of the machined workpiece surface 12, the course of the Andrückbands 42 fits Course of the workpiece surface to be machined 12 (for example, to larger workpieces 14, see FIG. 12 and to smaller workpieces 14 ', cf. FIG. 13 ).

The bearing elements 82 have on their side facing away from the constriction 84 a support surface 52.

The pressing device 30 according to Figures 12 and 13 The fixing device 87 comprises, for example, an actuating element 88 in the form of a screw which presses a fixing element 90 against the pressing belt 42 and this against the supporting surface 52 (FIG. compare FIGS. 14 and 15 ).

The bearing element 82 has, for example, a one-piece bearing body 92 which extends in the width direction 72 of the finishing strip 16 (cf. FIG. 15 ) extends between opposed side surfaces 94 and 96 (see FIG FIG. 18 ).

The bearing body 92 may be connected, for example by means of screws 98 with holding parts 100 (see FIGS. 15 and 12 ), which serves to attach the bearing member 82 to the holders 32 (see FIG. 1 ). The holding parts 100 can also be connected to a frame 102 (cf. Figures 12 and 13 ), which in turn is connected to a holder 32.

In the in the FIGS. 12 to 21 illustrated embodiment of a pressing device 30, the bearing surfaces 40 of the bearing element 82 a straight-line course. These bearing surfaces 40 correspond between their transition to the constriction 84 and to the support surface 52 surface portions of a cylinder jacket. These bearing surfaces 40 are used for mounting a Andrückbands 42, the pressing surface 66 is curved in profile, in particular concavely curved (see FIG. 15 ).

The support surface 52 of the bearing element 82 according to FIGS. 16 to 21 preferably extends in a straight plane.

In the in the FIGS. 22 to 27 illustrated embodiment of a bearing member 82 and a Andrückbands 42 for use in a pressing device 30 according to FIGS. 12 to 15 the bearing surfaces 40 a curved profile, in particular a concave curved profile, on. Such bearing elements 82 may in particular, as in FIGS. 25 to 27 represented, together with a Andrückband 42 are used, which has a rectangular cross section with a straight-profiled Andrückfläche 66 in an undeformed initial state, are used. When using such Andrückbands 42, the shape of the curvature of the bearing surface 40 transmits to the pressing surface 66 and on the Finishing belt 16 and on the workpiece surface to be machined 12th

But it is also possible, the bearing element 82 according to FIGS. 22 to 24 to use together with a Andrückband 42, which has a curved in profile pressure surface 66 (such a pressure belt 42 is, for example, in FIG. 21 shown).

For the following with reference to the FIGS. 28 to 33 described embodiments, reference is made to the above description. The Andrückbänder 42 according to FIGS. 28 to 33 have in contrast to the above-described Andrückbändern 42 openings 104, which are arranged in particular at the level of the constriction 84 and thus at the height of the effective region 20 of the finishing belt 16. It is possible that only one aperture 104 (cf. FIG. 29 ) is provided. It is also possible that a plurality of apertures 104 are provided (see FIG. 32 ).

The apertures 104 have an extension in the width direction 72 of the finishing tape 16 and an extension in the running direction 106 of the finishing tape 16.

In the event that only one opening 104 is provided, this may preferably be formed substantially elliptical or diamond-shaped.

FIG. 34 shows an enlarged illustrated target contour 108 of a workpiece 14, which is applied across the width direction 72 of the finishing belt 16. The desired contour 108 deviates from a circular cylindrical shape 110, namely by divergent workpiece material removal 112. The largest workpiece material removal 112 results for outer setpoint contour sections A, smaller workpiece material removal for the desired contour sections B, in turn smaller workpiece material removal for the desired contour sections C and no or only a slight material removal for a desired contour section D.

For sizing an in FIG. 35 illustrated interruption 104, a pressing belt 42 is provided, which seen in the width direction 72 of the finishing belt 16 has successive band sections (ABCDCBA). In this case, a band section D, which corresponds to a desired contour section D of the target contour 108 of the workpiece 14, is provided with an interruption 104 ', which is longer in the direction 106 of the finishing strip 16 than interruptions 104 ", which band sections C are assigned. which correspond with corresponding desired contour sections with larger material removal rates 112. Overall, for example, an arrangement according to FIG FIG. 35 , wherein mutually adjacent interruptions 104, 104 ', 104 ", 104"' together form a continuous interruption 104. Alternatively, the interruptions 104, 104 ', 104 ", 104"' but also be provided separately.

In a further refinement of the dimensioning of an interruption 104, the desired contour 108 of a workpiece 14 can also be described in the form of a particularly continuous and kink-free function, as in FIG FIG. 36 indicated by a coordinate system. For example, such a function is a circular function or a logarithm. Depending on the function, the course 114 of an opening 104 can then be determined (cf. FIG. 37 ).

With the example in Figures 35 and 37 illustrated interruptions 104 is achieved that seen in the width direction 72 of the finishing belt 16 different material removal rates 112 can be realized. Since the pressing belt 42 has a longer interruption in a central portion D in the running direction 106, the finishing belt 16 is pressed in this area with a lower voltage to the workpiece 12, so that there takes place a smaller material removal. On the other hand, the perforations in lateral strip sections (for example in strip sections B) are shorter in the running direction 106 of the finishing strip 16, so that in these strip sections the pressing strip 42 is pressed with greater force against the finishing strip 16 and a higher material removal takes place in these areas.

Claims (15)

1. Belt finishing device (10) comprising a pressing device (30) for pressing a finishing belt (16) against a workpiece surface (12), wherein the pressing device (30) comprises a pressure belt (42) which is supported on two spaced-apart bearing surfaces (40) as viewed in the running direction (106) of the finishing belt, (16), characterized in that at least one of the bearing surfaces (40) and/or the pressure belt (42) has a profile that deviates in the width direction (72) of the finishing belt (16) from a straight course.
2. Belt finishing device (10) according to claim 1, characterized in that the profile is curved.
3. Belt finishing device (10) according to one of the preceding claims, characterized in that the at least one bearing surface (40) and/or the pressure belt (42) has at least one discontinuity (104).
4. Belt finishing device (10) according to claim 3, characterized in that the discontinuity (104) is in the form of a pocket-shaped recess and/or in the form of an opening.
5. Belt finishing device (10) according to one of the preceding claims, characterized in that at least one of the bearing surfaces (40) is formed by a bearing roller (38).
6. Belt finishing device (10) according to claim 5, characterized in that the bearing roller (38) is floatingly supported.
7. Belt finishing device (10) according to claim 5 or 6, characterized in that the bearing roller (38) can be supported on a stationary bearing roller support device (60).
8. Belt finishing device (10) according to one of the preceding claims, characterized in that at least one of the bearing surfaces (40) is formed by a stationary bearing element (82).
9. Belt finishing device (10) according to one of the preceding claims, characterized in that a fixing device (87) for fixing the pressure belt (42) relative to the bearing surfaces (40) is provided.
10. Belt finishing device (10) according to one of the preceding claims, characterized in that the profile is provided on a pressing surface (66) of pressure belt (42) facing the finishing belt (16).
11. Belt finishing device (10) according to one of the preceding claims, characterized in that the pressure belt (42) is in the form of an endless belt.
12. Belt finishing device (10) according to claim 11, characterized in that a pressure belt support device (50) is provided, with which a rearward section (48) of the pressure belt (42), which is spaced from the finishing belt (16) and which extends between the bearing surfaces (40) arranged with a mutual spacing, is or can be supported.
13. Belt finishing system, comprising a belt finishing device (10) according to one of the preceding claims and a workpiece (14) having a workpiece (12) surface to be finish-processed, characterized in that at least one of the bearing surfaces (40) and/or the pressure belt (42) comprises at least an discontinuity (104), that the workpiece surface (12) is interrupted in the region of a bore, and that the position of the discontinuity (104) in the width direction (72) of the finishing belt (16) is matched to the position of the bore.
14. Method for producing a belt finishing device (10) according to one of the preceding claims, characterized in that the nominal contour (108) of a finish-machined workpiece surface (12) is determined, and that additionally at least one of the following measures is performed:

    - at least one of the bearing surfaces (40) or a pressing surface (66) of the pressure belt (42) facing the finishing belt (16) is provided with a profile that is identical to the nominal contour (108) or has a more pronounced contour;

    - at least one of the bearing surfaces (40) and a pressing surface (66) of the pressure belt (42) facing the finishing belt (16) is each provided with a partial profile, wherein a superposition of the two partial profiles is identical to the nominal contour (108) or has a more pronounced contour;

    - nominal contour sections are defined and removal of material (112) from the workpiece deviating from a circular cylindrical shape is determined for each of the nominal contour sections; at least one of the bearing surfaces (40) and/or the pressure belt (42) is provided with at least one discontinuity (104), wherein the discontinuity (104) is associated with a nominal contour section having lesser material removal (112) from the workpiece than the material removal (112) from an adjacent nominal contour section;

    - nominal contour sections are defined, and for each of the nominal contour sections deviating from a circular cylindrical shape (110) material removal (112) from the workpiece is determined; at least one of the bearing surfaces (40) and/or the pressure belt (42) is provided with discontinuities (104', 104"), which are each associated with a corresponding nominal contour section, wherein the discontinuities (104', 104") have different lengths as measured in the running direction (106) of the finishing belt (16), and discontinuities (104") having shorter lengths are associated with nominal contour sections having greater material removal rates (112) and discontinuities (104') having greater lengths are associated with nominal contour sections having lower material removal rates (112).
15. Method according to claim 14, characterized in that the profile and/or superposition of the two partial profiles is more pronounced than the nominal contour, and that the profile and/or the superposition of the two partial profiles delimits a segment of a circle, as viewed across an effective width of the finishing belt (16), with the segment height being greater by a factor from 1.5 to 25, preferably from 3 to 15, especially from 5 to 10, than a segment height of a segment of a circle that is delimited by the nominal contour (108), as viewed across the effective width of the finishing belt (16).

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