EP3369493B1 - Method for manufacturing a profile with pointing and metal drawing - Google Patents

Description

The invention relates to a method for producing a profile with a target dimension.

During continuous casting, which in particular involves drawing an extruded profile, in particular the primary material for extrusion is made from continuous casting, in particular a metallic profile, for example made of copper, is pulled through a forming die, so that after pulling through the continuous profile essentially the shape of the forming die and thus the profile has a target dimension.

When “threading” the profile to be pulled is pushed through into the forming die. This threading process is difficult to implement, particularly in cases in which delicate structures are to be created. This is, for example, because complex or fine structures bend and threading is therefore not possible or a large amount of waste is generated.

From the US 3,256,731 A1 , which forms the basis for the preamble of claim 1, the sharpening of an elongated metal element by chemical stripping is known, with the stripped tip of the metal element then being gripped on one side by a clamping device and on the other side by a sequence of short impacts is pressed into a calibration mold.

The WO 2007/122254 A1 apparently describes a method for sharpening an injection cannula by means of a device which has a tapered cavity into which one end of the tubular cannula is pushed, the opening of the cavity being vibrated at a frequency of over 10,000 Hz in the ultrasonic range in order to sharpen the cannula.

The object of the invention is to improve the state of the art.

The task is solved by a method for producing a profile with a target dimension according to claim 1.

The core of the invention is, in particular, that a profile is preformed in such a way that one end of the profile can be passed through a forming die and the profile can then be pulled through the forming die. The preforming of one end of the profile takes place by means of a recursively modulated axial forming, which causes a cutting surface of the structures of the profile to be successively reduced in size - and thus "sharpened". This recursive, modulated axial forming means that the delicate structures of a profile are not mechanically changed as much as if it were introduced directly into the forming die.

Because only a small change occurs in each step of the recursively modulated axial forming, this means that later processing through the forming die ("threading") can be guaranteed with very little waste.

This has an enormous advantage, particularly with plastic materials such as copper, as the yield is significantly increased and waste is significantly reduced. In addition, the manufacturing process can take place without interruption. Sharpening ensures that threading is reliable. After one end of the profile has been sharpened using recursively modulated axial shaping, the end can, for example, then be relocated automatically using a robot arm or the like and threaded into the format groove.

In addition, the invention makes it possible for the first time to "thread" filigree structures and to form a profile by pulling them through a forming die. This means that there is a completely new manufacturing process and the range of profile shapes can be significantly increased.

The following terms are explained:

A "profile" is also called a construction profile or assembly profile. Such profiles can, for example, have longitudinal grooves into which, for example, sliding blocks (also referred to as sliding blocks) can be pivoted.

The “target dimension” is in particular the dimension that the profile should have at the end of processing. Essentially, both the profile structure and the essential external dimensions are present. However, further treatment steps can be carried out, which essentially affect the strength and surface quality, but only have a very small effect on the dimensions of the profile cross section.

The target dimension is specified in particular by a “shaping die” through which, for example, a semi-finished copper product is “pulled”.

The forming die essentially realizes the cross-sectional area, which forms the shaped profile over a length by pulling. The forming die is therefore essentially responsible for the cross-sectional shape of the profile.

“Pulling through” is a forming process and is generally part of tension-compression forming. This is very often used for wire pulling. For example, drawing is carried out using drum drawing machines, straight drawing benches or continuous drawing machines.

The "initial profile" is a profile that has slightly larger dimensions than the profile after it has been drawn through the forming die.

With recursively modulated axial forming, the end of the initial profile is pressed further and further into a mold by means of an axial back and forth movement, which successively imprints a profile on the end of the initial profile, which is tapered and can be carried out by the forming die essentially without contact or correspondingly with little contact. In particular, due to this recursively modulated axial shape, fine or correspondingly filigree structures, especially in the case of copper, are not bent, but are successively fed into the corresponding shape. For each individual molding, a molding force with which the profile end is pressed into the mold and/or the depth with which the profile end is inserted into the mold can be adjusted. The recursive effect occurs several hundred times per second, with the optimal frequency being determined depending on the material, profile cross section, etc.

When "sharpening", the edges at the end of the starting profile are thinned out, thus reducing the cross-sectional area so that the end essentially forms a point. What is particularly important is that the edges are “sharpened” on both sides or accordingly all the way around so that threading into the forming die can be carried out in a reproducible manner. Thus, the edges of one end of the initial profile can have a cone or wedge. In particular, thanks to the recursively modulated axial shaping, these edges can also be tapered in a stepped or curved manner.

After the recursively modeled axial shaping has been completed, there is a “pointed profile” which has a “point” at its “profile end”. The pointed dimension is designed in particular in such a way that a partial insertion of the profile end of the starting profile can be introduced into the forming die without contact. The sharpened end of the profile can also have constant dimensions over a longer section, whereby the profile end of the initial profile can be guided completely through the forming die, so that at the end of the forming die the drawing tool can grip the profile end and produce the profile by pulling the initial profile through the forming die.

Profiles with complex geometries can therefore be realized for the first time, particularly for copper.

"Complex geometries" are in particular geometries in which a force vector orthogonal to a mirror axis or in the direction of a mirror point creates a contour at the profile end of the starting profile, which lies outside the contour of the forming die and thus forms contact with the forming die during threading and becomes one Bending the profile end of the starting profile would cause. For example, such complex structures can be webs in a hollow profile and the like.

The “contour” is formed in particular by the material surface of the profile, which is formed at the end of the profile when a cut is made.

In a related embodiment, the complex geometry is a thin-walled structure or structures, or it is a free element or there are several free elements, or it has a cavity or several cavities.
“Thin-walled structures” are in particular webs that cannot be produced using manufacturing processes according to the state of the art. These can range from a few tenths of a millimeter to 3 millimeters. “Thin-walled” profiles also mean in particular that a relationship between Wall thickness and external dimensions (e.g. diameter or edge length) are very large (>=1:10). Such profiles are also characterized by the fact that, due to this fact, such thin-walled profiles immediately bend when “pushed through” a die.

“Free elements” are, for example, grooves or corresponding tongues and the like in a hollow profile.

“Two cavities” are formed, for example, by one cavity being delimited by a web.

In order to ensure easy sharpening, the recursively modulated axial shaping is carried out using a pointed die, which in particular has an axially conical shape cross section.

The “point size die” is the component that imprints the shape for “threading through” on the end of the starting profile. The pointed die therefore thins out the edges of the profile end.

In order to produce an initial profile, it can be produced by continuous casting. In particular, copper or copper alloys in particular are used in continuous casting.

In a further embodiment, the initial profile is pressed or rolled, so that a pressed and/or rolled initial profile, in particular a pressed and/or rolled continuously cast initial profile, is present. This can influence the strength of the profile.

A pointed die for recursively modulated axial forming has an axially conical cross section, so that a sharpened profile is achieved by means of recursively modulated axial forming Has a pointed dimension that is true to shape and in which only the wall thickness of the profile is reduced. This allows a profile to be produced that ensures the desired shape and dimensional stability.

A device for recursively modulated axial forming has a pointed die as described above.

Figur 1

eine stark schematische Querschnittsdarstellung eines Kupferprofils mit einem Ausgangsprofil, einem Profil mit einem Spitzmaß und einem Profil mit einem Zielmaß,

Figur 2

einen stark schematischen Herstellungsvorgang eines angespitzten Profils in einer Seitendarstellung und

Figur 3

eine stark schematische Querschnittsdarstellung eines Stranggussziehprofils mit mehreren dünnwandigen Strukturelementen, mehreren Hohlräumen und einem freien Element.

The invention is explained in more detail using an exemplary embodiment. Show it

Figure 1

a highly schematic cross-sectional representation of a copper profile with a starting profile, a profile with a pointed dimension and a profile with a target dimension,

Figure 2

a highly schematic manufacturing process of a sharpened profile in a side view and

Figure 3

a highly schematic cross-sectional representation of a continuously cast drawing profile with several thin-walled structural elements, several cavities and one free element.

An initial profile 103 made of a copper alloy has the contour of a double-T beam. This initial profile 103 was obtained by casting and subsequent rolling. In an alternative, the initial profile was obtained by extrusion. As soon as the initial profile 103 has been processed by means of recursively modulated axial shaping in a pointed die 223, a profile 105 with a pointed dimension is given at one profile end 211.

The profile with pointed dimension 105 is dimensioned smaller than the profile with target dimension 101, this profile 101 corresponding to the desired product shape.

To produce the end product with a profile with the target dimension 101, the initial profile 103 is introduced into a pointed die 223 step by step in the recursive axial shaping direction 241. The force and the depth with which the starting profile 103 is inserted into the pointed die is set based on the copper alloy, so that each time the starting profile is inserted, the end of the profile is only shaped but not bent.

With each step, the starting profile 103 is inserted a little further into the pointed die 223 and then pulled out a short distance again. After 400 steps, the starting profile 103 then has the profile with a point 105 at one profile end 211.

The starting profile 103 with the profile with a pointed dimension 105 located at the profile end 211 is then pulled out of the pointed dimension die 223 and threaded through the forming die 221 so that a profile end 211 protrudes from the forming die 221. This profile end 211 is gripped by a gripper (not shown) and pulled through the forming die 221 by a pulling device (not shown).

A profile with target dimension 101 is thus impressed on the starting profile 103. Only the profile end 211 has different dimensions than the desired profile with target dimension 101. The unwanted part is separated and the end product is available.

Different complex geometries can therefore be realized. This is particularly evident from a cross-sectional area of a profile (see Figure 3 ). Thus are different connecting webs 357, 359, 361, 363 or individual elements such as a mushroom element 351 and in particular thin webs 351 can be implemented.

Reference symbol list

101

Profile with target dimension

103

Initial profile

105

Profile with pointed dimension

207

Pointed profile

211

End of profile

221

Forming die

223

Pointed die

241

recursive axial form direction

301

complex profile

351

thin bridge

353

cavity

355

Mushroom element

357

first connecting bridge

359

second connecting bridge

361

third connecting bridge

363

fourth connecting bridge

Claims (6)

1. Method for producing a profile (101) having a target dimension having the following steps

   - sharpening an end of a starting profile (103) such that the profile has a meeting point at a profile end (211) and a sharpened profile (207) with a sharpened end is present

   - guiding the sharpened profile through a shaping die (221) and subsequently

   - passing the sharpened profile through the shaping die such that after the passing the profile has substantially the target dimension,

   characterised in that

   - the sharpening is carried out by means of recursive modulated axial shaping, wherein the end of the starting profile is pressed increasingly into the shaping die by means of an axial to and fro movement, which shaping die successively stamps a profile on the end of the starting profile, wherein the recursive axial shaping is carried out several 100 times a second.
2. Method according to claim 1, characterised in that the profile has a complex geometry.
3. Method according to claim 2, characterised in that the complex geometry has a thin-walled structure (351), thin-walled structures, a free element (355), several free elements, a hollow space (353) and/or several hollow spaces.
4. Method according to any of the preceding methods, characterised in that the recursive modulated axial shaping is carried out by means of a pointed die (223), which in particular has an axially conical shape cross-section.
5. Method according to any of the preceding claims, characterised in that the starting profile is produced by means of extrusion moulding, such that an extrusion moulded starting profile is present.
6. Method according to any of the preceding claims, characterised in that the starting profile is pressed and/or rolled, such that a pressed and/or rolled starting profile, in particular a pressed and/or rolled extrusion moulded starting profile, is present.

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