The invention proceeds from the prior art as is known from WO 2009/12 45 34 A2 and EP 2 460 499 B1.
The invention uses substantially an identical device and an identical method as are described in the two above-mentioned documents. For this reason, reference can be made to the content of the disclosure of the two above-mentioned documents, which is also the subject matter of this invention in its entirety, with regard to the basic functions of the present invention and the device structure.
A disadvantage in the method and the device according to WO 2009/124534 A2 is that the movable forming head, in which cassettes for receiving profile rollers are distributed circularly with the mutual spacing on the circumference, requires a relatively large amount of space. The core of this document is that the forming head is applied from the outside to the sheet metal part to be formed, and as a result the cassettes, in which the profile rollers are arranged, are also applied from the outside to the sheet metal part to be formed and deform the sheet metal part oriented inward in the radial direction. Alternating internal and external gear teeth are thus applied to the sheet metal part, wherein the deformation occurs by way of profile rollers to be applied externally to the sheet metal part.
Such a device and such a method have proven themselves to a large extent. However, it is a disadvantage that sheet metal parts which have a flange oriented outward cannot be provided with gear teeth. Because the known tool having the vertically movable forming head is applied from the outside to the sheet metal part, an outwardly oriented flange on the sheet metal part would make forming no longer possible.
A further disadvantage of the known device is that the forming head requires a lot of space. For this reason, an external roller receptacle must be arranged on the cassettes, which absorbs the pressure, which is oriented radially outward, of the profile rollers on the cassettes. Such a pressure absorbing part or such an absorbing ring is relatively difficult to produce and must be implemented as relatively stable, and requires corresponding installation space.
A further disadvantage is that the known device is restricted to profile rollers as forming bodies.
The object of the invention therefore is that of refining a method and a device for producing an internally and externally toothed pot-shaped sheet metal part so that with less required space and lower production costs of the forming head, sheet metal parts having an outwardly oriented flange can also be formed.
To achieve the stated object, a method according to the subject matter of WO 2009/12 45 34 A2 is characterized in that the forming movement of the forming body is performed in the direction from the radial inside to the radial outside on the sheet metal part.
The essential advantage results in the case of the given technical teaching that now, instead of a deformation pressure and a deformation direction from the outside to the inside, the invention now proposes performing an equivalent deformation oriented from the inside to the outside on the sheet metal part. This means that the forming head is introduced from above into the upper open receptacle of the sheet metal part and provides the sheet metal part with the alternating internal and external gear teeth on the circumference oriented from the inside to the radial outside.
Insofar as the forming head according to the invention operates with profile rollers, it is referred to hereafter as a roller head. However, this name is also maintained if other forming bodies are used instead of the profile rollers, for example, the alternative pressing and drawing forming tool bodies mentioned hereafter.
The term “profile roller” used here in the description of the invention is accordingly not to be understood as restrictive. All forming bodies or drawing or pressing bodies can be used, for example, pressure pieces which operate in the nature of a metal spinning tool or also axle-free rollers, balls, cylinders, pins, and the like.
Particularly in the case of the use of axle-free balls accommodated in the respective cassette (miniroll rolling bodies), the advantage results that multiple such balls (miniroll rolling bodies) can also be accommodated in one cassette. They can be arranged axially aligned one over another or axially aligned offset in relation to one another in the forming direction in the cassette.
However, they can also be mounted in an axle-free manner in a cassette located adjacent to one another in the same plane or located adjacent to one another in various planes.
With the given technical teaching, the essential advantage now results that the forming head must be at least as large in its external circumference as the internal circumference of the sheet metal part to be formed. The necessity results therefrom of producing a forming head having a relatively small structure, which is in turn linked to the advantage that the actual force absorption of the cassettes can now be provided in the center of the forming head, and a stop bushing having relatively small circumference can be arranged there, which absorbs the entire, inwardly oriented forming pressure, which acts on the cassettes.
Instead of a stop ring arranged on the external circumference, as in WO 2009/12 45 34 A2, which must absorb the outwardly oriented forming pressure of the cassettes with a large diameter, instead an internal stop bushing is provided in the center of the forming head of the present invention, which for this reason can be implemented as substantially simpler, more cost-effective, and in a more space-saving manner.
The invention accordingly provides in principle that a forming head extends into a clamped, pot-shaped sheet metal part, and because of the forming bodies rolling along the wall of the sheet metal part on the inner circumference, which are preferably profile rollers, alternating internal and external gear teeth are produced, because the sheet metal part is surrounded on its outer circumference by an associated die provided with complementary gear teeth.
The ring-shaped die accordingly acts with its gear teeth as a support body for applying the gear teeth in the sheet metal part. While the forming bodies operate oriented from the inside to the outside, the die having its complementary gear teeth is applied to the outer side of the sheet metal part
The invention is not restricted to a forming head, on which the cassettes having outwardly oriented forming bodies (preferably profile rollers) are arranged and which is introduced into the interior of the sheet metal part to be formed.
In a refinement of the invention, it is provided that a combination of the forming according to WO 2009/12 45 34 A2 and the present invention is proposed as a novel roller head or forming head.
Such a combined roller head or forming head consists of a ring of external cassettes, the forming bodies (preferably profile rollers) of which are oriented radially inward on the outer circumference of the sheet metal part to be formed, and furthermore a further roller head or forming head according to the present invention combined therewith, which is equipped with a number of cassettes arranged distributed uniformly on the circumference, the forming bodies (preferably profile rollers) of which act from the inside toward the outside.
It is therefore possible for the first time using the invention to also form sheet metal parts, which have a stop or parts which protrude beyond the internal circumference of the sheet metal part, using a roller head or forming head which acts from the inside to the outside.
In the prior art, it was always necessary in the case of sheet metal parts, in the case of which a collar or attachments of an large diameter were formed on, to form the collar on the sheet metal part later, after the alternating internal and external gear teeth were applied.
This is no longer necessary according to the present invention, because the collar can be formed on to the unformed pot-shaped sheet metal part, and using this outwardly oriented collar, the unformed sheet metal part can then nonetheless be formed into an internally and externally toothed pot-shaped sheet metal part.
The quality of the part is therefore substantially improved, because a subsequent application of a collar by a separate forming operation can be omitted. During such a preceding forming operation, the precision of the later gear teeth can be impaired.
In a refinement of the present invention, it is moreover also provided that a stripper which is movable separately from the forming head (preferably roller head) is arranged on the upper tool of the device. This stripper ensures the ejection of the sheet metal part after completed forming operation.
In the following description of the drawings, a set of forming bodies (roller set), which is not adjustable during the forming operation, is described, which is characterized in that the cassettes accommodating the forming bodies (the profile rollers) press against linear, cylindrical guide surfaces on the inner stop bushing and therefore are not radially adjustable during the forming operation.
In this case, the invention is not restricted to cassettes which are only arranged in one plane on the forming head (roller head), a combination of multiple cassettes located one above another is also possible to carry out the forming according to the invention.
Such combinations of multiple cassette rings are used to implement different processing steps, for example, post-processing of the applied gear teeth using a further set of profile rollers.
In an alternative embodiment to the above-mentioned exemplary embodiment, a radial adjustment of the forming bodies (profile rollers) in the direction toward the workpiece to be formed is performed in such a manner that, for example, the back plates, which are supported on the tool-side stop bushing, of all cassettes seated on the ring, having a thickness X1 are each replaced by a back plate having a different thickness X2 and therefore the cassettes protrude radially outward more overall than in comparison with thinner back plates, which ensure that the cassettes protrude with a smaller amount radially out of the forming head (roller head).
Accordingly, the depth of the forming of the gear teeth can be adjustable by replacement of the respective back plate on the respective cassette.
In a third embodiment of the invention, it is provided that the back plates of the cassettes do not press against guide surfaces, which are cylindrical and aligned in parallel to the movement direction of the forming head (roller head), on the tool-side stop bushing, but rather that the guide surfaces are aligned at a conical angle in the direction toward the working direction of the forming head (roller head).
In this embodiment, it is possible to perform a radial adjustment of the cassettes during the downward stroke, in that using a suitable pressure ring, which is driven so it is displaceable in the axial direction, the cassettes on their conically beveled back plates are moved on guide surfaces of the stop bushing, which are also conically beveled, and therefore a continuous or also step-by-step adjustment of the radio forming depth of the cassettes is provided during the forming operation.
In a third embodiment, it can also be provided that the cassettes are not aligned in the radial direction oriented precisely from the inside to the outside, and accordingly the profile rollers also operate on a radius beam, but rather they are installed from an angle position deviating from a radius beam in the cassette or the cassette is seated in a deviating angle beam on the stop bushing, as described, for example, in DE 10 2010 053 547 A1.
The invention thus provides a device and a method, in which it is provided in a refinement that the profile rollers or forming bodies do not operate on a radius beam, but rather offset at an angle to the radius beam.
A movable adjustment using a pressure ring, wherein a continuous change of the rolling depth of the profile rollers or the penetration depth of the forming bodies occurs, is described in WO 2009/12 45 34 A2 in
The invention begins here, which transfers such an adjustment capability to a roller head or forming head, in which the cassettes act on the sheet metal part applied to the external circumference in a manner oriented from the radial inside to the radial outside.
The invention thus also claims the combination of a known roller head according to WO 2009/12 45 34 A2 with a roller head or forming head as will be described hereafter on the basis of
With a further embodiment of the invention, it is provided that a double-walled, pot-shaped sheet metal part is optionally provided with different or identical gear teeth both on the inner wall and also on the outer wall.
For this purpose, in a first processing step, a die or another ring-shaped folder is inserted between the inner wall and the outer wall of the sheet metal part, wherein the die has complementary gear teeth in comparison to the gear teeth rolled on by the profile rollers.
Such gear teeth of the die can optionally only act on the radial outer circumference of the sheet metal part or can only act on the radial inner circumference of the sheet metal part or can act on both circumferences of the sheet metal part with different or identical tooth shapes.
Using such an embodiment, it is accordingly possible for the first time to produce a double-walled sheet metal part, the internal gear teeth of which deviate from the external gear teeth.
The inventive subject matter of the present invention results not only from the subject matter of the individual patent claims, but rather also from the combination of the individual patent claims with one another.
All specifications and features disclosed in the documents of the application, including the abstract, in particular the spatial implementation illustrated in the drawings, are claimed as essential to the invention, insofar as they are novel over the prior art individually or in combination.
The invention will be explained in greater detail hereafter on the basis of drawings which illustrate multiple embodiments. In this case, further features essential to the invention and advantages of the invention result from the drawings and the description thereof.
In the figures:
a: shows a perspective illustration of a double-toothed workpiece
b: shows a section through the workpiece according to
c: shows a perspective bottom view of the workpiece according to
The forming device according to
A number of downwardly oriented guide columns 3 are provided on the upper tool 1, which plunge into the guide receptacles 4 when the upper tool 1 is lowered in the arrow direction 27 toward the lower tool 2.
In this manner, the upper tool 1 is centered in relation to the lower tool 2.
On the lower tool 2, a recess is arranged in a clamping plate 44, in which a counter holder piston 7 is held so it is movable via further holding plates. The drive of the counter holder piston is not shown in greater detail. It plunges through a ring space 24, which is arranged centrally in the interior of a ring receptacle 10.
A die 5 having associated, inwardly oriented gear teeth 6 is arranged on the ring receptacle 10. The sheet metal part 9, which is not yet formed, is seated on the die 5, wherein internal centering is performed via the forming plate 8. A gap is present between the outer circumference of the forming plate 8 and the inner circumference of the die 5 provided with the gear teeth 6.
In the exemplary embodiment shown, the sheet metal part 9 has an outwardly oriented flange 43, which is equipped with a larger circumference. An application of gear teeth by a forming head (roller head 23), as is described in the prior art, would therefore not be possible.
For this reason, the invention provides that a forming head 23 is provided with forming bodies (profile rollers 22), which are oriented from the inside toward the outside.
According to
Two sets of forming bodies in the implementation of profile rollers 22 are arranged in two working layers 36, 37 lying one above the other (see
Two stop bushings 21 located one above the other are provided, which are connected together by a central fastening screw 19, so that this fastening screw 19 holds together the entire package having the stop bushings 21 and the cassettes 17, 18, which are arranged in two working layers and at a mutual distance to one another.
The lower ring of cassettes 18 is held and guided by a lower indexing plate 20, while the upper ring of cassettes 17 is held and guided by an upper indexing plate 35.
In the functional position shown in
In
In this method step, the stripper 14 would now be seated with its ring plate 13 on the formed sheet metal part 9, which is provided with the internal and external gear teeth, and will hold this part back while the upper tool 1 moves back upward.
The removal of the sheet metal part which is thus formed is then performed according to
Two different working positions 36, 37 are provided, which assume a mutual distance 38 from one another, wherein a ring of cassettes 17, 18 arranged distributed uniformly on the circumference is provided on each working position 36, 37.
The number of the cassettes 17, 18, which are arranged uniformly distributed on the respective circumference of the working positions 36 and 37, is dependent on the fineness and the indexing of the desired gear teeth in the sheet metal part 9.
It is important in any case that each collar of cassettes 17, 18 is formed by an internal stop bushing 21, against the internal circumference and outwardly oriented circumference of which the respective back plates of the cassettes 17, 18 press. In this manner, the forming pressure which acts from the profile rollers 22 on the cassettes 17, 18 is transmitted via the cassette housing to the back plate and from there to the external circumference of the respective stop bushing 21.
For this reason, the stop bushings 21 can be installed in a space-saving manner and absorb the entire forming load, whereby the small structure circumference of the roller head 23 results.
The entire package of the lower indexing plate 20, the stop bushing 21 located in between, the upper indexing plate 35, and the upper stop bushing 21 is held together by the central fastening screw 19.
It substantially consists of a back plate 25, which is provided in the exemplary embodiment shown at a uniform thickness 45, which extends over the entire height of the cassette 17, 18.
The back plate 25 is screwed together by means of fastening screws 28 with the housing 29 of the cassette.
The front side of the cassette is formed by a closure plate 34, in which a front recess is provided, by which the profile of the axle-free profile roller 22, which is mounted so it is rotatable in the interior of the cassette, is received.
Accordingly, a bearing surface 30, which encloses the outer circumference of the profile roller 22 and receives it in a formfitting manner, is provided in the interior of the cassette 17, 18. Lubricating grooves or other bearings (not shown in greater detail) can be provided.
It can also be provided that the profile roller 22 is not received in an axle-free manner in the bearing surface of the recess in the interior of the cassette 17, 18, but rather that in this region the profile roller 22 is rotatably mounted with an axis in the cassette. It is also mounted so it is rotatable in the receptacle in the two arrow directions 32, and therefore on the bearing surface 30.
In a third embodiment of the invention, it can be provided that instead of a profiled profile roller (an example of a profile is shown in
The receptacle in the cassette with the bearing surface 30 is selected in any case so that when the closure plate 34 is removed by loosening the fastening screws 28, the profile roller 22 can be removed and replaced.
The rotational axis 31 is therefore only shown schematically, because it is an axle-free mounted profile roller 22.
As described above, however, the profile roller 22 can also be received with a stub axle in the rotational axis 31 so it is rotatable in the cassettes 17, 18.
In another embodiment according to
The guide surface 46 is formed in this case on the outer circumference of the respective stop bushing 21.
For securing in location, guide attachments 42 are formed on the base sides of the respective cassette, which are aligned in the radial direction and are guided so they are displaceable in associated radial grooves 40 of the indexing plate 20.
In this manner, the cassettes 17, 18 are held so they are easily replaceable, on the one hand, on the base surface of the indexing plate 20 and, on the other hand, with their internal circumference on the external circumference of the stop bushing 21.
In
The type of the profile edges is oriented according to the type of the desired gear teeth.
The combination of two roller heads 23, 23a, of which one forming set operates from the inside to the outside in the roller head 23 and the other forming set operates from the outside to the inside in the roller head 23a, is heretofore not known from the prior art, however.
Using this novel profile combination roller head 23, 23a, it is now possible for the first time to apply first gear teeth 51 on the outer circumference of a sheet metal part 9 and to apply second gear teeth 50 on the inner circumference of the same sheet metal part.
It is not necessary for the solution in this case for the two roller heads 23, 23a to operate on the same plane; they can also, as a sequential tool, for example, first form the sheet metal part 9 oriented from the inside to the outside following one another in succession and in the second forming step then form the sheet metal part, which has already been formed from the inside to the outside, also subsequently from the outside to the inside.
In a further embodiment, using the combination of the two roller heads 23, 23a, it is possible for the first time to provide a double-walled pot-shaped sheet metal part 9 on both coaxial circumferences 48, 49 with gear teeth 50, 51.
Such a double-walled sheet metal part 9 is visible in
For this purpose, as shown in
In a similar manner, the profile rollers 22, which are oriented radially from the inside toward the outside, manufacture gear teeth 50 on the inner circumference 49 of the inner ring of the sheet metal part 9. The associated die 5a also has gear teeth 52 complementary to the gear teeth 50 here.
The die 5a can also be a uniform ring-shaped part, which has the complementary gear teeth 52a on the outer circumference, and the complementary gear teeth 52 on the inner circumference. In this embodiment, the gear teeth 50, 51 can be produced on the double-walled workpiece 9 in a single work operation
The deep-drawing tool according to
This exemplary embodiment, in which a deep-drawing tool having a leading forming edge 54 firstly plunges into the internal circumference of the sheet metal part 9-1, can be used for all above-described embodiments.
Number | Date | Country | Kind |
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10 2014 002 971 | Mar 2014 | DE | national |