Patent Application
20240261840
The invention relates to the field of producing profilings, in particular by way of cold forming, for example in rotationally symmetrical solid or hollow parts.
Various methods for profiling solid or hollow parts in a cold-forming manner are known from the state of the art.
For example, it is known to provide hollow parts with a profiling in a single step by way of a non-profiled sheet metal part being reshaped by a device which includes a multitude of tools which are distributed over a circumference and which on insertion of the sheet metal part into the device engage into the sheet metal part where profile gaps are to be produced. A corresponding method for manufacturing a pot-like sheet metal part having an inner and/or outer toothing with teeth which run to the middle axis of the pot is known for example from DE102014002971A1.
The disadvantage of such methods is the fact that they are not very flexible, since for example a change of the profile gap shape renders necessary a replacement of all tools, and a resetting to the machining of sheet metal parts with another diameter necessitates the creation of a new, correspondingly adapted device.
In other cold-forming methods, workpieces are periodically machined in a hammering manner by way of tools driven in an orbiting manner for producing a profiling, as is known for example from WO 2005/075125 A1. This method is very flexible in its application since a resetting to other products or changed product specifications is possible with very little effort. Furthermore, the method permits the production of very long profilings, even if this demands a large reshaping of the material, such as for example for toothings with a large module in solid material. On the other hand, a leading of a profiling up to close to a shoulder which projects radially outwards to a large extent is not so easily possible with the method known from WO 2005/075125 A1 due to the orbiting movement of the tools.
A method which permits a profiling into a workpiece up to close to an outwardly projecting shoulder of the workpiece is known for example from WO 2007/009267 A1. In the method which is described there, a cylindrical thin-walled hollow part which is seated on an outer-profiled mandrel is provided with a profiling which runs essentially parallel to the longitudinal axis of the hollow part in a cold-forming manner by way of at least one profiling tool being made to strikingly act in a hammering manner upon the hollow part from the outside radially to the longitudinal axis of the hollow part. Herein, the profiling tool is brought to act upon the surface of the hollow part in each case in an oscillating manner in a direction which is perpendicular to the longitudinal axis, thus by way of a radially running, linear to and fro movement. And the profiling tool, given an unchanging radially feed depth, is displaced axially relative to the hollow part until the desired profile length is achieved, wherein the machining of the hollow part can be begun at an outwardly projecting shoulder of the hollow part.
Given particularly high demands on the surface quality, it can be necessary, subsequent to the method according to WO 2007/009267 A1, to carry out a post-machining of the hollow part since the hollow part is only machined in a short axial section by the profiling tool with each engagement, which can result in a slight scaly roughness.
Furthermore, a method which permits profilings to be produced up to very close to a shoulder which projects far radially outwards is known from WO 2020/099536. The method also permits profilings to be produced even if this necessitates a large material reshaping, for example in the case of toothing with a large module, above all in solid material. And furthermore, a high surface quality can be achieved with the method, wherein this as a rule requires no post-machining, wherein however at least in solid material, the length of the profilings produced in such a manner is quite limited, at all events if high quality demands are placed upon the profiling.
It is an object of the invention to provide a method for manufacturing a profile body which is provided with a profiling, as well as corresponding devices which do not have the aforementioned disadvantages.
For example, it is to be rendered possible to simply and inexpensively retrofit the method or the device for the manufacture of other products or for the realisation of amended product specifications.
A further possible object of the invention is to permit a profile creation with a particularly high surface quality.
A further possible object of the invention is to produce profilings of a large length, in particular concerning profilings which require a large reshaping of the material such as for example regarding toothings with a large module, in particular in solid material.
A further possible object of the invention is to permit a particularly precise profiling creation, in particular in solid material and given large profiling lengths.
A further possible object of the invention is to permit a profile creation with a particularly high productivity.
A further possible object of the invention is to permit a profiling up to close to a workpiece projection, for example close to an outwardly projecting shoulder of the workpiece which is to be profiled.
A further possible object of the invention is to permit a profiling between two profiling delimitation structures and up to close to these.
At least one of these objects can be achieved by devices and/or methods which are described hereinafter.
In the method, a tool holder and with this a tool which is held by the tool holder is driven into a complex movement which includes at least two components, specifically an orbiting movement for example along an orbiting path, similarly to a planet, and a rotation movement about its own axis. Herein, these two movements are synchronised with one another. The orbiting movement can be a periodic movement. A suitable drive device can be provided for producing the rotation movement.
By way of the orbiting movement, the tool holder and herewith also the tool can be periodically led up to a workpiece to be machined and act upon this in a reshaping manner and then distance itself from the workpiece again, in order to subsequently approach this again etc. For example, the tool can be brought into reshaping engagement with the workpiece once per orbit (or also with every second or every third orbit).
On account of the provision of a rotation movement of a tool axis about the rotation axis of the tool holder together with the orbiting movement of the tool holder, said provision being explained in more detail hereinafter, the tool can repeatedly machine the workpiece in a cold-forming manner in a novel way. The tool can include an active region which repeatedly machines the workpiece in a machining region of the workpiece. Herein, a rotation direction of the tool holder about the rotation axis in particular can be counter to a rotation direction of the orbiting movement.
Although similar to the method from the mentioned WO 2005/075125 A1, important differences between the methods result from the difference of the tool axis and tool holder rotation axis (which are identical in WO 2005/075125 A1), as will become clear later.
An engagement of the tool into the workpiece in each case during a short time duration can therefore take place periodically (due to the orbiting movement) and within this short time duration in which the tool (more precisely: the active region of the tool) is in contact with the workpiece, the tool as the case may be not only rotates about the tool axis, but also about the rotation axis of the tool holder, so that (during the mentioned short time duration) a movement of the tool which can be counter to the orbiting movement is added additionally to the orbiting movement which is provided by the tool holder. Thus, the length of a contact region in which the active region of the tool is in contact with the workpiece during a reshaping engagement can therefore be less than would be the case with the method according to the mentioned WO 2005/075125 A1. Furthermore, this clearly differs from the non-hammering, but rolling machining as is known for example from the mentioned WO 2020/099536.
The machining of the workpiece for creating the profiling is composed of a multitude of individual machining steps along the axial extension of the profile, said steps being axially offset to one another and only overlapping one another to a low extent. A high surface quality and above all a high precision of the profiling can thus be achieved. Accordingly, a post-machining as can be necessary in the case of the method according to WO 2007/009267 A1 given particularly high demands on the surface quality can be avoided.
Due to the rotation movement of the tool holder about its own axis together with the mentioned synchronisation, it is rendered possible for the tool holder to be situated in a desired or predefined azimuthal alignment, for example always in the same azimuthal alignment, when the tool is brought into engagement with the workpiece. On account of the mentioned rotation movement, a change of the azimuthal alignment of the tool holder takes place during each engagement, and the azimuthal alignment for example with each engagement of the tool changes in the same manner over the time duration of the engagement.
For example, the rotation movement of the tool holder can be synchronised with the orbiting movement of the tool holder such that the tool holder runs, for each of the reshaping engagements, through the same azimuthal orientations.
In the present text, the terms azimuth and azimuthally, inasmuch as not specified otherwise, relate to the rotation axis of the tool holder.
The synchronisation permits a useful application of a tool which is mounted to be rotatable about a tool axis which is different from the mentioned rotation axis. In particular, a tool which has a rotationally symmetrical active region can be applied. The tool can thus for example be a roller as is known for example from the mentioned WO 2005/075125 A1.
Due to the intrinsic rotation of the tool holder about its rotation axis whilst the tool axis is rotating about the rotation axis, the tool after the engagement has been effected can distance itself from the workpiece again relatively rapidly, so that a contact with a workpiece projection, for example a workpiece shoulder can be avoided and thus a reshaping of the workpiece projection by the tool can be avoided.
An axial advance of the workpiece can be provided in order to achieve the desired axial extension of the profiling.
For example, the rotation movement can take place during the complete orbit or in a continuous manner. By way of this, a good synchronising ability of the rotation movement of the tool holder with the orbiting movement of the tool holder can be achieved.
For example, the synchronisation of the two movements can be realised mechanically. Thus, a mechanical synchronisation device can be provided for this synchronisation. The mentioned movements however can also be synchronised with one another differently, for example electronically, thus by way of an electronic synchronisation device.
In some embodiment examples, the mentioned synchronisation device, also denoted hereinafter as a second synchronisation device includes a planetary gear. For example it can include a ring gear and a planet wheel which runs in the ring gear, wherein the planet wheel can represent a part of the tool holder or at least be fixedly connected to the tool holder or co-rotates about the rotation axis with the rotation movement of the tool holder and also participates in the mentioned orbiting movement. The axis of the planet wheel can be coaxial to the rotation axis.
On the other hand, the planetary gear can also drive the tool holder for its rotation movement about its rotation axis. The drive device which has already been mentioned above and is for producing the rotation movement of the tool holder about its rotation axis of the tool holder can therefore include a planetary gear.
Herewith, a planetary gear which simultaneously generates the rotation movement of the tool holder about its rotation axis and synchronises this rotation movement with the orbiting movement of the tool holder can be provided.
The mentioned, for example planetary orbiting movement can be imparted to the tool holder by an orbiting body. The tool holder can be mounted in the orbiting body, in particular be mounted to be rotatable about its rotation axis. The orbiting body for example can execute a rotation about an orbiting body axis, and the rotation axis of the tool holder is distanced to the orbiting body axis, so that the rotation axis carries out an orbiting movement essentially along a circular path.
If the mentioned planetary gear is envisaged, this orbiting movement can generate the rotation movement of the tool holder, provided by the planetary gear. For this, the orbiting body axis can be aligned coaxially to an axis of the ring gear. Accordingly, the already aforementioned drive device for producing the rotation movement of the tool holder about its rotation axis can therefore include the orbiting body and a planetary gear. Likewise, a drive shaft for during the orbiting body into its rotation about its orbiting body axis can belong to the mentioned drive device.
A drive shaft for driving the orbiting body into its rotation about its orbiting body axis, additionally to the orbiting body can also belong to a drive device for producing a movement of the orbiting body.
Furthermore, a radial feed of the tool holder—perpendicular to a longitudinal axis of the workpiece or of a workpiece holder which holds the tool—can be provided, so that in the course of the machining an ever deeper engagement of the tool into the workpiece is rendered possible. The tool holder can be fed radially so far until a desired profile depth is reached.
For example, the radial feed can be realised by way of the orbiting body or at least an orbiting body axis of the orbiting body being moved towards the longitudinal axis, thus in this context undergoing a radial advance.
For example, the orbiting body can be mounted in a profiling head, in particular be mounted in the profiling head to be rotatable about its orbiting body axis, and the profiling head is drivable into a movement towards the longitudinal axis. Accordingly, the orbiting body whilst it rotates about its orbiting body axis can be moved towards the longitudinal axis by way of a drive for the radial feed. And the orbiting body axis can accordingly be moved towards the longitudinal axis.
By way of this, the described complex movement of the tool holder (and of the tool) can yet include a further component, specifically the described movement (radial feed movement) which runs radially to the longitudinal axis. The rotation axis of the tool holder can accordingly execute a movement which results from a circular movement which is superimposed with a linear movement of the centre point of the circle, in particular wherein the linear movement takes place in a plane which is defined by the circular movement.
Furthermore, a rotation movement of the workpiece or of the workpiece holder about the longitudinal axis can be provided, for example generated by way of a suitable drive device, for example by way of a torque motor, so that the workpiece can be machined by way of the tool at difference positions which are distributed over the circumference of the workpiece. Thus, different profile gaps of the profiling to be produced can be produced by way of the tool. As is explained further below, several tools can be provided, so that a single tool (or each of the tools) does not necessarily contribute to the formation of all profile gaps of the profiling. Despite this, one can envisage the tool coming into engagement with the workpiece at every position along the circumference of the workpiece, at which position a profile gap of the profiling is to be produced, and thus contributing to the formation of all profile gaps of the profiling.
The mentioned rotation movement can have a varying rotation speed, in particular one which periodically varies at least partially. The mentioned rotation movement can for example be an intermittent rotation.
One can envisage the rotation speed of the rotation movement of the workpiece or of the workpiece holder having successive phases of a relatively high rotation speed and a relatively low rotation speed. The machining of the workpiece by the tool in particular can take place each during the phases of a relatively low rotation speed. The more slowly the workpiece rotates during the engagement of the tool or the longer the workpiece rotates slowly or is at a standstill in the phases of a relatively low rotation speed, the better can a high precision of the finally produced profiling be achieved.
For example, one can envisage the tool machining the workpiece in those phases of the rotation movement in which the workpiece is at a standstill. For example, one can envisage the tool machining the workpiece in phases of the rotation standstill of an intermittent rotation of the workpiece (the rotation speed at rotation standstill is zero).
On the other hand, it is also possible to envisage the mentioned rotation movement having a constant rotation speed. This can result in an increased productivity.
A synchronisation of the rotation movement of the workpiece holder with the orbiting movement of the tool holder can be provided. By way of this, it can be ensured that the machining of the workpiece takes place again and again at the same positions along the circumference of the workpiece.
For example, a respective synchronisation device which hereinafter is also denoted as a first synchronisation device can be an electronic synchronisation device.
In the embodiment example outlined above, with a planetary gear and orbiting body, the first synchronisation device for example can synchronise the drive for the rotation of the workpiece or workpiece holder with the drive shaft for driving the orbiting body into its rotation about its orbiting body axis.
The method can thus in particular be a method for manufacturing a profile body which is provided with a profiling by way of cold forming a workpiece, wherein the workpiece can have a longitudinal axis and in a machining region an outer surface, into which the profiling is to be incorporated. The outer surface can be extended along the longitudinal axis. In particular, the outer surface can be concentric to the longitudinal axis, for example conical or cylindrical. Other shapes of the outer surface, for example polygonal ones, for example given prismatic machining regions, are however also possible.
Herein, the workpiece executes a rotation movement about the longitudinal axis. And the workpiece, in particular the mentioned outer surface is machined by a tool in a multitude of successively executed reshaping engagements, in which the tool or more precisely an active region of the tool comes into contact with the machining region. The respective tool movement is also described further above.
The tool is held by a tool holder, and the tool holder is mounted in an orbiting body to be rotatable about a rotation axis of the tool holder and is driven into a rotation movement about its rotation axis. And the tool holder is driven by the orbiting body into an orbiting movement; in particular the tool holder is driven by the orbiting body into a movement along an orbiting path.
The tool is mounted in the tool holder to be rotatable about a tool axis, wherein the tool axis is not identical to the rotation axis of the tool holder.
In particular, the tool axis can be distanced to the rotation axis of the tool holder. The two axes can be aligned for example parallel to one another. In the general case, which also includes axes which are not aligned in a parallel manner, “distanced” means that the axes, understood mathematically as straight lines, do not intersect.
If one compares the method which is described here with that in the mentioned WO 2005/075125 A1, one finds that given roughly the same diameter of the orbiting body, roughly the same amount of force is available for the reshaping, so that given large diameters, large reshapings are also possible in solid material and for large toothing modules. However, in the method which is described here, a length of a stretch (parallel to the axis of the workpiece holder or parallel to a direction of the profiling), in which the tool is close to the workpiece, for example a length of a stretch, along which the tool (more precisely: the active region of the tool) is in contact with the workpiece during the engagement, can be shorter than is the case in the mentioned WO 2005/075125 A1. The reason is that due to the superposition of the orbiting movement with the rotation movement of the tool holder given a non-coaxial mounting of the tool in the tool holder, the tool movement in the proximity of the workpiece can be described as a movement along a hypocycloid, for example an ellipse, and this in turn, in the proximity of the engagement, can be approximately described as a circular movement, wherein the diameter of this circular movement can be significantly smaller than the diameter of the orbiting movement. Thus, it is possible to generate profilings up to closer to an outwardly projecting shoulder of the workpiece to be profiled than is the case according to the method of WO 2005/075125 A1 given the same orbiting movement.
However, profilings up to similarly close to an outwardly projecting shoulder of the workpiece to be profiled can also be produced in the method according to the mentioned WO 2005/075125 A1. However, this only functions if the orbiting diameter is selected accordingly small, for example similarly small to the just mentioned diameter of the circular movement. However, this results in the forces which are available for the reshaping of the workpiece then being significantly smaller, so that for example large toothing modules in solid material cannot be manufactured.
If on the other hand one compares the method described here with the method from the mentioned WO 2020/099536 (with a sectoral tool), one finds that here quasi arbitrary profiling lengths can be produced, with a good quality which is constant along the whole profiling. In contrast, in the method according to WO 2020/099536 this is only the case with profiling lengths which correspond maximally to the length of the active region of the sectoral tool. This is because the material behaviour, in particular the flow behaviour of the workpiece material as a rule is not constant along the profiling, so that narrow profiling tolerances can hardly be kept to given long profilings. For example, the material of a tubular workpiece at a workpiece end can be deformed and flow more easily than in the middle of the workpiece. Hence the ability to apply the method with a sectoral tool according to WO 2020/099536 tends to be limited to short profilings.
In particular, the tool can be freely rotatable about the tool axis. The tool can thus be brought into rotation about the tool axis by way of the engagements into the workpiece.
The tool can include an active region which is rotationally symmetrical with respect to the tool axis. In this manner, the result of an engagement can be independent of a rotation orientation of the tool with respect to the tool axis, said orientation being present during the engagement.
The tool can be embodied, for example, as a roller.
Furthermore, one can envisage:
In particular, one can envisage the rotation movement of the workpiece being synchronised with the orbiting moment of the tool holder such that at each of a number of different positions distributed over a circumference of the workpiece, several of the reshaping engagements take place. If an outer profile is to be created, the mentioned positions can be positions at which profile gaps of the profiling are to be created. If by way of the method an inner profiling of the workpiece is produced, the positions can be such positions which lie between adjacent profile gaps of the inner profiling which are to be created.
And in particular, one can also envisage the rotation movement of the tool holder being synchronised with the orbiting movement of the tool holder such that, for each of the reshaping engagements, the tool runs through the same azimuthal orientations.
If the rotation movement of the tool holder is synchronised with the orbiting movement of the tool holder such that azimuthal orientations which the tool runs through during the respective reshaping engagement are identical for each of the reshaping engagements, then for example one can create a profiling which goes up to close to a profiling delimitation structure, for example to a workpiece projection.
Furthermore, one can envisage a relative movement of the workpiece with respect to the orbiting body taking place parallel to the longitudinal axis for the advancing formation of the profiling in the workpiece. In particular, the orbiting body, as described above, can include an orbiting body axis, about which it rotates, and a relative movement of the workpiece with respect to the orbiting body axis takes place parallel to the longitudinal axis.
For example, the workpiece is drivable into a movement parallel to the longitudinal axis (axial advance).
By way of an axial advance, one can succeed in the tool engagements taking place at different axial positions (with respect to the longitudinal axis) in the course of the method. For example, a workpiece holder which holds the workpiece is drivable in a direction parallel to the longitudinal axis by way of a drive.
The method can also be seen as a method for profiling a workpiece and/or as a method for producing a profiling in a workpiece.
The workpiece can be a hollow part, in particular a rotationally symmetrical, for example cylindrical hollow part.
The workpiece can be a solid part, in particular a rotationally symmetrical, for example cylindrical solid part.
The workpiece can be a metal workpiece.
The machining region can be a region, into which the profiling is to be incorporated, thus a region which is to be profiled. The machining region can be an axially limited section of the workpiece, for example an end-piece of a tube-like or rod-like workpiece.
The workpiece can include a second region which connects onto the machining region. This second region, adjacent to the machining region, can include a profiling delimitation structure, for example a workpiece projection, which at least in an (azimuthal) angular region about the longitudinal axis has a radial extension which is larger than a radial extension of the outer surface in the machining region where this is adjacent to the workpiece projection. The profiling delimitation structure can be a profiling obstacle, for example a workpiece shoulder.
A profiling delimitation structure can form an end or a delimitation of the profiling.
The outer surface in the machining region can be for example rotationally symmetrical, for example cylindrical or also conical. The outer surface however can also be designed differently from this, for example polygonally.
The profiling can be an outer profiling. This can be created in a hollow part or in a solid part. Concerning hollow parts for example, it is also possible for an outer and inner profiling to be produced simultaneously, if for example if one envisages the workpiece in its machining region being seated on an outer-profiled mandrel. Furthermore, it is also possible for an inner toothing to be produced in a hollow part without an outer toothing also yet being simultaneously produced by way of this. For this, one can also envisage the workpiece in its machining region being seated on an outer-profiled mandrel.
The profiling can include a multitude of profile gaps (deepenings of the workpiece in the machining region) which are distributed over the circumference, in particular are for example distributed uniformly over the circumference. The profile gaps however can also be distributed over the circumference in a non-uniform manner.
The orbiting movement of the tool holder can be a continuous movement and in particular can be effected at a constant speed.
The rotation movement of the tool holder can be a continuous movement and in particular can be effected at a constant rotation speed.
In particular, these two speeds can have a ratio to one another which is constant in time.
The orbiting movement can be a circular movement.
A trajectory (movement path) which describes the movement of the tool holder in particular can result from a superposition of the orbiting movement with a (radial) movement which is perpendicular to the longitudinal axis.
In some embodiments, the orbiting body executes a rotation about an orbiting body axis. By way of this the orbiting movement of the tool holder can be generated. The orbiting movement of the tool holder can a take place in a plane which is perpendicular to the orbiting body axis.
The orbiting body axis and the rotation axis can be aligned parallel to one another.
A rotation direction of the rotation movement of the tool holder (about the rotation axis) can for example be opposite (opposite rotation direction) to a rotation direction of the orbiting movement (about the orbiting body axis).
The orbiting movement of the tool holder can take place in a plane, to which the longitudinal axis is aligned in parallel, and/or a plane which is perpendicular to the tool axis is perpendicular to a plane which is perpendicular to the longitudinal axis. In particular, this can be provided for producing a profiling which runs parallel to the longitudinal axis, for example a straight toothing, in particular if the rotation movement of the workpiece or of the workpiece holder slows down during the engagement or an intermittent rotation movement is provided.
On the other hand, a different alignment can be provided for example if an oblique toothing is to be produced or if the workpiece still rotates during the engagement, such as for example given a constant rotation speed of the workpiece or of the workpiece holder. For example, one can then envisage a plane which is perpendicular to the tool axis enclosing a pivoting angle with the longitudinal axis, said pivoting angle being different to zero. This pivoting angle can be selected for example in dependence on the obliqueness angle of the profiling or on the rotation speed of the workpiece or workpiece holder during the engagement.
The rotation of the orbiting body can be a continuous movement and in particular have a constant rotation speed. And the rotation movement of the tool holder can be a continuous movement and in particular have a constant rotation speed. And these two rotation speeds can have a temporally constant ratio to one another. A synchronisation of these two rotation speeds can be achieved for example by way of a planetary gear, as already described above.
The planetary gear can include a ring gear and a planet wheel which runs in the ring gear. The planet wheel can be part of the tool holder. And it can execute the rotation movement together with this. The position of the planet wheel can be fixed relative to the position of the tool axis.
The ring gear can be fixed in a profiling head, in which the orbiting body is mounted, in particular rotatably mounted.
The profiling head can be a bearing housing for receiving or mounting parts of the device. For example,
Furthermore, the profiling head can be actively connected to a drive, for example to a linear drive, for the radial feed.
Two profiling heads can also be provided, each with at least one tool, for example with a first tool in a first profiling head and a second tool in a second profiling head. These can be arranged lying opposite one another with respect to the longitudinal axis, for example in a mirror-imaged manner with respect to a plane which contains the longitudinal axis. Both tools can be, embodied, for example, as a roller.
The two profiling heads, in particular including the device parts such as orbiting body and ring gear which are provided in them, can be designed equally or be manufactured according to the same specifications, wherein the movements of the device parts run in a mirror-imaged manner with respect to a plane containing the longitudinal axis.
The respective orbiting movements of the two mentioned tools can be different from one another, specifically in particular run to one another in a mirror-imaged manner to a plane which contains the longitudinal axis. Herein, the respective orbiting movements of the two mentioned tools can take place in one and the same plane.
The orbiting movement of the first tool (first profiling head) can thus be synchronised with the orbiting movement of the second tool (of the second profiling head) such that the reshaping engagements of the two mentioned tools take place simultaneously.
On account of the (mirror) symmetrical construction, a mechanical loading of the workpiece holder can be kept low, since the respective forces which are directed towards the longitudinal axis essential cancel one another.
Several tools can also be provided for other reasons and at other locations, for example within the same profiling head. These for example can be designed in the same manner. The tools can be for example rollers, in particular rollers which are designed in the same manner. If several tool holders are provided, these can also be designed in the same manner.
On the one hand a single tool holder can hold two or more tools, for example such that their tool axes are distributed in a uniform manner azimuthally with respect to the rotation axis of the tool holder.
For example, these tools can reshapingly engage into the workpiece in an alternating manner during successive orbits.
By way of this, an increased service life of the individual tools can result.
On the other hand, two or more tool holders can be provided and these each hold (at least) one tool. The orbiting movements of these tool holders can describe for example the same orbiting path and they can be uniformly distributed along the orbiting path. For example, these tool holders can be distributed in a uniform manner azimuthally with respect to the orbiting body axis.
For example, one engagement into the workpiece can take place per rotation orbit of the orbiting body per tool holder.
By way of this (given the same number of orbits of the orbiting body), a multiplication of the engagements per time and thus a quicker machining of the workpiece can be achieved. During a rotation period of the orbiting body, N reshaping engagements can take place, wherein N specifies the number of tool holders each with (at least) one tool.
If N specifies the number of tool holders each with n tools and two equally (for example mirror-imaged) constructed bossing heads are provided, then the machining of the workpiece can thus take place with 2·N·n tools.
The tools or at least their active regions can be manufactured for example according to the same specifications.
As described, the tool can be a roller.
In its active region, the tool can have a shape which in a section along a section plane corresponds to the negative of the shape of a profile gap of the profiling which is to be produced, wherein this section plane runs through the active region and contains the tool axis. For the case that a plane which is perpendicular to the tool axis is aligned perpendicularly to a plane which is perpendicular to the longitudinal axis, one can envisage the tool having a shape which corresponds to the negative of the shape of a profile gap of the profiling to be produced, in a section perpendicular to the longitudinal axis through the active region during an engagement.
In particular, this can be provided if the profiling includes or is an outer profiling. Optionally, an inner profiling can yet also be produced simultaneously with the outer profiling—or also not.
The active region can be rotationally symmetrical with respect to the tool axis.
The active region can be defined in that it is the region of the tool, in which the tool comes into (direct) contact with the workpiece. However, one can envisage only a section of the active region coming into (direct) contact with the workpiece given each engagement. Given a tool which is freely rotatably mounted about the tool axis, it is essentially random as to which section of the active region comes into (direct) contact with the workpiece with each engagement.
If the tool as described is held by the tool holder, the tool axis can co-rotate with the associated tool holder. And if a planet wheel which is part of the tool holder is provided, the relative position of the tool axis to the planet wheel can also be constant.
The tool can be part of a tool insert of the tool holder which can be fixed on at least one further part of the tool holder.
The device can be a device for manufacturing a profile body which is provided with a profiling, by way of cold forming a workpiece. For this, the device can include:
Furthermore, the device can include:
The tool holder can include a rotation bearing which defines a tool axis which is different from the rotation axis of the tool holder, for receiving the tool; and specifically such that the tool is rotatable about the tool axis. In particular, the tool can be freely rotatable about the tool axis.
In some embodiments, the device includes the tool, mounted in the rotation bearing to be rotatable about the tool axis.
In particular, one can envisage the tool:
The drive device for producing a rotation movement of the tool holder about its rotation axis can at least partly be identical to the second synchronisation device. For example, the already described planetary gear on the one hand can be part of this drive device by way of it converting the movement of the orbiting body into the rotation movement of the tool holder, and on the other hand it can be part of the first synchronisation device (or correspond to the first synchronisation device) by way of it coupling the rotation movement of the tool holder to the orbiting movement of the tool holder.
The drive device for producing a movement of the orbiting body can include for example a drive spindle. This can also be part of the drive device for producing a rotation movement of the tool holder about its rotation axis, e.g., imparted by the planetary gear.
The orbiting body can be mounted in a profiling head, in particular be rotatably mounted. And it can, by way of a drive, be driven towards the longitudinal axis, namely for the radial feed movement. The drive can for example by a drive for a movement of the profiling head which runs perpendicularly to the longitudinal axis.
The device can include a drive device for producing a movement of the workpiece holder parallel to the longitudinal axis. By way of this, tool engagements can take place bit by bit at positions which lie increasingly further from an end of the workpiece. A formation of the profile which advances parallel to the longitudinal axis can be rendered possible.
The first synchronisation device and the second synchronisation device can be one and the same synchronisation device or completely or partly be different from one another.
The first synchronisation device can be configured to ensure that an orbiting frequency of the orbiting movement of the first tool holder is in a fixed (temporally unchanged) ratio to a speed of the rotation movement of the workpiece.
The second synchronisation device can be configured to ensure that an orbiting frequency of the orbiting movement of the first tool holder is in a fixed (temporally unchanged) ratio to a speed of the rotation movement of the tool holder.
The device can be configured such that the cold forming of the workpiece can take place by way of a multitude of successively carried out reshaping engagements. These can be engagements of the same tool or also engagements of several tools.
And the first synchronisation device can be configured to synchronise the rotation movement of the workpiece holder with the orbiting movement of the tool holder such that at each of a number of different positions distributed over a circumference of the workpiece, several of the reshaping engagements take place.
The device can be configured such that a tool comes into contact with the machining region in each of the reshaping engagements. In particular, the device can be designed such that the active region (more precisely: a section of the active region) of a tool comes into contact with a machining region in each of the reshaping engagements. The respective tool (more precisely: its active region or active region section) can herein act upon the outer surface (in the machining region) in a hammering manner. A tool can act upon the machining region in a cold-forming manner with each of the engagements.
And the second synchronisation device can be configured to synchronise the rotation movement of the tool holder with the orbiting movement of the tool holder such that the tool axis runs through the same (small) region of azimuthal positions (with respect to the rotation axis) in each of the reshaping engagements of the tool.
If several tools and one or more tool holders (in each case holding at least one of the tools) are envisaged, then one can envisage the second synchronisation device being configured to synchronise the rotation movement of the at least one tool holder with the orbiting movement of the respective tool holder such that each of the tool axes runs through the same (small) region of azimuthal positions (with respect to the rotation axis) in each of the reshaping engagements of the respective tool.
For example, if the profiling which is to be produced includes r profile gaps and the device include N tool holders whose orbiting movement describe one and the same orbiting path, then the first synchronisation device can be configured for example such that an Nth of a period duration of the orbiting movement is equal to an integer multiple of an rth of the period duration of the rotation movement of the workpiece. By way of this, the engagements take place precisely at the positions along the circumference of the workpiece where profile gaps are to be produced. In particular, the first synchronisation device can be configured for example such that an Nth of a period duration of the orbiting movement is equal to an rth of the period duration of the rotation movement of the workpiece. By way of this, the engagements each take place at adjacent profile gap positions.
The invention includes devices with features which correspond to the features of described methods and vice versa methods with features which correspond to the features of described devices.
Further embodiments and advantages are to be derived from the dependent patent claims and the figures.
The subject-matter of the invention is hereinafter explained in more detail by way of embodiment examples and the accompanying drawings: There are shown schematically:
Parts which are not essential for the understanding of the invention to some extent are not illustrated. The described embodiment examples are exemplary for the subject-matter of the invention or serve for its explanation and have no limiting effect.
The workpiece 1 in the shown example includes a machining region 11 which is rotationally symmetrical with respect to the longitudinal axis Z and is with an outer surface 11a and is, by way of example, cylindric and in which a profiling is to be incorporated and onto which a second region 12 connects, in which second region the workpiece 1 has a larger diameter than in the machining region 11. By way of this, a profiling delimitation structure which is designed as a workpiece shoulder 13 is formed between the regions 11 and 12.
Furthermore, an orbiting body 8 which is represented symbolically in
The tool holder 5 includes a rotation axis W, about which it carries out a rotation movement R5. This rotation movement R5 can be generated for example in a direct manner by a drive (rotation drive) or however be derived from the movement R8′ of the orbiting body 8, for example in a mechanical manner, for example by way of a planetary gear as will yet be described in more detail hereinafter.
The tool holder 5 holds at least one tool 2 which includes an active region 21, in which it comes into cold-forming contact with the workpiece 1, and specifically by way of it carrying out a movement during an engagement into the workpiece 1, said movement being described in more detail hereinafter. The tool 2 is mounted, in particular freely rotatably mounted in the tool holder 5, to be rotatable about a tool axis Q. The tool axis Q is not identical to the rotation axis W of the tool holder 5. By way of example, it can be aligned parallel to this and be distanced thereto.
The tool 2 can include a rotationally symmetrical (with respect to the tool axis Q) active region.
The tool 2 can be embodied, for example, as a roller.
Profile gaps in the workpiece 1 are produced by way of the tool 2, wherein the tool 2 executes a multitude of engagements per profile gap.
In order for the tool 2 to be able to engage into the workpiece 1 at different positions which are distributed over the circumference of the workpiece 1, the workpiece 1 can be driven into a rotation movement R1 about the longitudinal axis Z by way of the tool holder 10, in particular wherein the rotation movement R1 can be an intermittent rotation so that the tool engagement can each take place in a phase of the rotation standstill of the workpiece 1.
Furthermore, a drive for an axial advance of the workpiece 1 parallel to the longitudinal axis Z can be provided. By way of this, an advancing formation of the profiling along the longitudinal axis Z can be achieved.
Active connections for the purpose of the drive are represented in
A drive device A1 for producing a rotation movement R1 of the workpiece holder 10 is provided, for example a torque motor or another rotation drive, and a drive device A8 for producing the movement R8′ of the orbiting body 8. The drive device A8 can for example include a drive shaft.
And yet a drive device A5 is provided for producing the rotation moment R5 of the tool holder 5 about its rotation axis W is provided, as already specified above.
The rotation axis W is aligned parallel to the orbiting body axis. The orbiting movement R8 of the tool holder takes place in a plane, to which these axes are perpendicular. In the represented example, the longitudinal axis is aligned parallel to this plane.
The tool axis Q can be aligned parallel to the rotation axis W.
In order for the tool engagements to take place where profile gaps are to be produced, the workpiece rotation R1 and the orbiting movement R8 are synchronised with one another by way of a first synchronisation device Si, for example by way of the workpiece rotation R1 and the movement R8′ of the orbiting body 8 being synchronised with one another by way of the first synchronisation device Si.
For example, the synchronisation can lie in the two movements (R1 and R8 or R8′) having a temporally constant ratio of their orbiting times. For example, if only one tool 2 is provided and successive engagements of the tool 2 into the workpiece 1 are to be effected in each case into adjacent profile gaps, then T8/T1=z can be selected, with an orbiting time (period) T8 of the orbiting movement R8 of the tool holder 5 and an orbiting time (period) T1 of the workpiece, wherein z is the number of profile gaps to be produced.
This synchronisation can be realised for example by way of an electronic synchronisation device Si. Other synchronisation devices, for example mechanical ones however are also basically conceivable.
Furthermore, a second synchronisation device S5 is yet also provided, by way of which the rotation moment R5 of the tool holder 5 and the orbiting movement R8 of the tool holder 5 are synchronised with one another. This can be realised for example by way of an electronic synchronisation device, wherein this can then also be identical to the first synchronisation device Si. In the represented embodiment example, this synchronisation is realised mechanically, specifically by way of the already mentioned planetary gear.
In as much as this is concerned, the drive device A5 can be at least partly identical to the second synchronisation device S5, specifically by way of the planetary gear on the one hand generating the rotation movement R5 and on the other hand effecting the synchronisation between the rotation movement R5 and the orbiting moment R8.
By way of the synchronisation which is accomplished by the second synchronisation device S5, one can succeed in the tool axis Q assuming the same azimuthal alignment (with respect to the rotation axis W of the tool holder 5) during each engagement into the workpiece 1. This can be advantageous for example if the workpiece 1 as is represented in
By way of the second synchronisation device S5 one can succeed for example in the tool 2 coming into contact with the workpiece 1 and thus reshaping it in a hammering manner only in a small azimuthal angular region, which here for example is close to 0°, with each orbit.
Due to the superposition of the orbiting movement of the tool holder with the rotation movement of the tool holder about the rotation axis, one succeeds in the tool 2—due to the tool axis and rotation axis not being identical—being in contact with the workpiece 1 only for a very short time and along an only very short section (for example measured parallel to the longitudinal axis Z).
One can therefore prevent the tool 2 from coming into (reshaping) contact with the workpiece shoulder 13—but despite this the formation of the profile can take place up to close to the workpiece shoulder 13.
As can be simply recognised by way of
The tool holder 5 can for example includes a tool insert 2e (in
The tool axis Q can be fixedly positioned in the tool holder 5 relative to the planet wheels 45.
The planetary gear 40 includes a ring gear 41 with an axis 42 and apart from this can yet include a second ring gear which is not represented in
The axis 46 of the planet wheel 45 is coaxial to the rotation axis W. And the orbiting body axis V (corresponding to the axis of the orbiting movement of the tool holder) is coaxial to the axis 42 of the ring gear 41.
By way of a suitable dimensioning of the planetary gear 40, for example one can ensure that the tool axes Q at a certain position along the orbiting path U (see
Instead of a planetary gear with two ring gears and two planet wheels, the planetary gear can for example also be realised with not more than one ring gear and not more than one planet wheel.
The mechanical demands on the workpiece holder 10 can be greatly reduced if two tool engagements take place with each engagement of the tool, and specifically at locations of the workpiece 1 which lie opposite one another with respect to the longitudinal axis, and in particular also axially (with respect to the longitudinal axis Z) at the same position.
The profiling heads 3a, 3b or the parts which are mounted in them can be designed essentially in the same manner but mirror-imaged with respect to the movements.
By way of this, the workpiece 1 which is represented in a symbolised manner in
The movements of the two orbiting bodies can accordingly be synchronised with one another or result from one and the same movement, for example of one and the same rotation drive. And one or more ring gears can be fixed in each of the profiling heads.
In the course of the machining, it can be advantageous if the workpiece can be moved axially, thus in a direction parallel to the longitudinal axis Z, in order to permit an advancing formation of the profiling along the longitudinal axis Z by way of a multitude of successive tool engagements into the workpiece. This of course is also the case if only a single profiling head is provided or the tool engagements only take place from one side or in each case do not take place by way of more than a single tool.
Such an axial movement is symbolised in
For this, a drive AZ can be provided for the axial advance.
In the course of the machining, it can be advantageous if the tools can be fed radially, thus in a direction perpendicular to the longitudinal axis Z, since with an increasing number of engagements the profile gaps being formed become ever more deeper. This also applies if only a single profiling head is provided or a tool engagement only takes place from one side or in each case does not take place simultaneously by way of more than a single tool.
Such a radial feed movement is symbolised in
For this, a drive A2 for the radial feed can be provided.
Due to the radial feed, the trajectory or the movement path of the tool holder results from a superposition of the orbiting movement U with the (linear) radial feed movement, as is schematically illustrated in
By way of (as the case may be per profiling head) several tool holders 5a1, 5a2, . . . being provided, several engagements can take place per one orbit of an orbiting body, which can permit a quicker machining and thus a creation of the profiling within a shorter time.
By way of several tools being provided per tool holder, their service life can be increased and thus a longer interruption-free profiling can be made possible. For example, the second synchronising device S5 (see
Furthermore, it is illustrated in
The profile body 1p is a hollow part which is seated on an outer-profiled mandrel 6 and includes an outwardly projecting shoulder 13. On account of the use of a profiled mandrel 6, not only can an outer profiling be produced by the method but also yet simultaneously an inner profiling.
Concerning solid parts or hollow parts which are seated on non-profiled mandrels, one can produce an outer profiling without an inner profiling being simultaneously co-produced.
Furthermore, it is possible to produce an inner toothing in a hollow part, without an outer profiling being produced in the hollow part.
Profiling delimitation structures can also be directed radially inwards, relative to the adjacent section of the machining region.
Of course, a single workpiece can include two or more different machining regions, which for example can be axially distanced to one another and which in each case are provided with a profiling in the manner which is described in this text.
Concerning the examples which are represented in
However, one can also envisage a plane which is perpendicular to the tool axis enclosing a pivot angle δ (not equal to zero degrees) with the longitudinal axis, as is represented schematically in
For example, the profiling head can be pivoted so that the tool axis Q, the rotation axis W (of the tool holder) and the orbiting body axis V can be simultaneously pivoted.
If the tool axis Q, the rotation axis W and the orbiting body axis V are parallel to one another, then for example these can all be pivoted about the same pivoting angle δ. The plane which is perpendicular to the tool axis Q then on account of the mutual paralellities is also perpendicular to the rotation axis W and to the orbiting body axis V.
As has already been explained further above, the method which is described here can also permit the production of profilings which require large forces for this, wherein despite this a formation of the profiling up to close to the profiling delimitation structures (such as for example workpiece shoulders) is possible.
| Number | Date | Country | Kind |
|---|---|---|---|
| 00654/21 | Jun 2021 | CH | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/065014 | 6/2/2022 | WO |
