Device and method for producing a metal thread

Abstract

Method and device for producing a component (1) with a threaded region (2) in a stamping process from a blank (12) with a substantially cylindrical section (16), characterized in that the threaded region (2) is formed in the form of at least one at least partially circumferential recess (3) with a thread pitch (g) by axially inserting a thread core (46) with a partially or completely circumferential core contour region (49) into an interior space (13) of the substantially cylindrical section (16) of the blank (12), and the at least one at least partially circumferential recess (3) with a thread pitch (g) is stamped by a plurality of sliders (40) arranged circumferentially around the substantially cylindrical section (16) of the blank (12) by synchronously displacing the plurality of sliders (40) radially inward.such that the material of the essentially cylindrical section (16) is formed into the threaded section (2) essentially circumferentially between the core contour region (49) of the thread core (46) and slide contour regions (44) provided radially on the inside of the slides (40), wherein for the synchronous movement of the slides (40) radially inward, a number of essentially axially arranged drive wedges (27) is provided, each with a radially inner guide surface (31) widening in the closing direction (63) of the tool, which corresponds at least to the number of slides (40), and the drive wedges (27) are displaced in the closing direction (63) to close the slides (40), wherein the radially inner guide surfaces (31) of the drive wedges (27) slide on radially outer slide guide surfaces (41) widening correspondingly in the closing direction (63), and the slides (40) synchronously shift radially inwards.,

Description

TECHNICAL FIELD

[0001] The present invention relates to methods for producing threads from, in particular, metallic materials, as well as devices for carrying out such methods and threads produced using such methods. STATE OF THE ART

[0002] Threaded container closures can be manufactured in a variety of ways and using different materials. Thermoplastic or thermosetting materials, such as plastics, can be processed into such components using an injection molding process. Ductile materials, such as metal, can typically be formed into a thread using a rolling process, for example, by rolling a cylindrical section of a blank into a thread. PRESENTATION OF THE INVENTION

[0003] The known rolling processes for producing a thread, for example from metal, are problematic because the component and / or the tool must be rotated during machining.

[0004] The present invention provides an alternative procedure for producing a thread, with the advantages presented below, and a corresponding device for carrying out such a method.

[0005] Accordingly, according to a first aspect, the present invention relates to a method for producing a component having a threaded region in a stamping process from a blank having a substantially cylindrical section.

[0006] The method is characterized in that the threaded region is formed in the form of at least one at least partially circumferential recess with a thread pitch by axially inserting a thread core with a partially or completely circumferential core contour region into an interior of the substantially cylindrical section of the blank.

[0007] The at least one at least partially circumferential recess with thread pitch is embossed by a plurality of slides arranged circumferentially around the substantially cylindrical section of the blank, in that the plurality of slides are synchronously displaced radially inwards, so that the material of the substantially cylindrical section is formed or embossed to form the threaded section substantially circumferentially between the core contour region of the thread core and slider contour regions provided radially on the inside of the slides.

[0008] For the synchronous movement of the slides radially inwards, a number of essentially axially arranged drive wedges with a radially inner guide surface which each widens in the closing direction of the tool is provided, at least corresponding to the number of slides, and these drive wedges are moved (synchronously) in the closing direction to close the slides, wherein the radially inner guide surfaces of the drive wedges slide on radially outer slide guide surfaces which widen correspondingly in the closing direction and displace the slides synchronously radially inwards.

[0009] The thread is formed with cross slides. The inner side is supported. To relieve the material in the groove area during forming, axial compression (upsetting) can be applied at the same time. Ideally, the upsetting process is forced and not regulated by spring force. After forming, the core is removed, e.g., by a rotary motion.

[0010] In this way, a relatively small number of slides are required, typically fewer than 20, to reliably form a thread in an efficient process. The advantage here is that each slide is individually controlled by its own drive key. The benefit of individual control is that each slide can be individually adjusted for the process, allowing the conditions to be optimally set across the entire circumference. This makes it possible to work with a comparatively small number of slides, thus keeping the number of moving parts in the tool to a minimum. A further advantage is that the guide surfaces can be designed as flat planes rather than curved planes, which also contributes to the adjustability, reliability, precision and ease of manufacture of the tool.On the other hand, it is also possible to design the guide surfaces as curved planes in a very targeted manner in order to regulate the speed of the radial movement of the slides depending on the machining phase. For example, the guide surface can be set flatter for a critical machining phase, allowing the slides to move radially inward more slowly during this machining phase.

[0011] The finished and final thread can also be formed in several such stages, whereby the successive stations or thread segments are rotated at a certain angle to each other around the axis of the tool.

[0012] According to a first preferred embodiment, the method is accordingly characterized in that fewer than 20 slides and a corresponding number of fewer than 20 drive wedges are provided distributed over the circulation, wherein preferably in the range of 10-19, particularly preferably in the range of 15-18 slides and a corresponding number of drive wedges are provided.

[0013] A further preferred embodiment is characterized in that the drive wedges are attached to a common block, wherein this attachment preferably allows the aforementioned individual adjustment of the drive wedges. The adjustment can be achieved via specific individual adjustment means, but it is also possible to achieve this adjustment by deformation, surface treatment, or displacement of elements, in particular the drive wedges.

[0014] A further preferred embodiment is characterized in that the drive wedges are fastened to a block which is axially offset from the cavity of the tool and which has the drive wedges as rod-shaped elements directed in the axial direction towards the cavity, which are distributed over the circumference with intermediate spaces, and whose respective inner link surface is preferably designed as a flat plane.

[0015] The slider gate surfaces are preferably designed as flat surfaces.

[0016] A further preferred embodiment is characterized in that the substantially cylindrical portion of the blank is pressed in the axial direction during the forming of the threaded portion.

[0017] The thread core can be designed as a rigid element that is turned out of the interior of the threaded component when the tool is opened.

[0018] The thread core can also be designed as a radially expandable element, which, in the expanded state, provides a substantially continuous, circumferential core contour area for the stamping process of the threaded area. It can be contracted, at least in the core contour area, into a state with a smaller circumference. In this contracted state, it is moved out of the interior of the threaded component without rotation in the axial direction when the tool is opened. Preferably, the expandable element has at least three wedge-shaped circular segment elements. Such designs are known, for example, from DE102011011784A1.

[0019] The threaded component and / or the blank preferably contains metal or consists of metal, preferably aluminum and its alloys (e.g. aluminum according to DIN 1712 or e.g. AI 99), copper and its alloys or iron and its alloys, in particular steel, e.g. in the form of tinplate / light sheet according to DIN 1616 (e.g. TH 435, TH 550, SF 600) or alloys of these systems.

[0020] The metal preferably has a thickness in the range of 80 µm - 1 mm, preferably in the range of 150 - 500 µm, particularly preferably in the range of 200 - 400 µm.

[0021] The metal may have a paint or coating on at least one or both sides.

[0022] A further preferred embodiment is characterized in that the blank is prepared for the process in a punching process and / or forming process and / or coating process, i.e., such steps precede the process. The blank can be prepared in this way, for example, from a supplied sheet metal strip. The blank can have a central through-opening or a base on one side.

[0023] The blank may further comprise a circumferential flange at one or both axial ends, wherein the flange is preferably oriented radially inwardly or radially outwardly, in particular at an angle of 80-100° to the axis of symmetry of the blank.

[0024] The blank is preferably a cup-shaped blank, preferably with a circumferential flange pointing radially outwards at the opening.

[0025] The threaded component may be a screw cap or a part thereof, or at least a section of a container for a screw cap, preferably a dome section for such a container, in particular a gas-tight and / or liquid-tight container.

[0026] The outer diameter of the thread is typically in the range of 5-100 mm, in particular in the range of 7-50 mm or in the range of 10-30 mm.

[0027] The thread depth in the thread area is typically in the range of 0.3-5 mm, preferably in the range of 1-3 mm.

[0028] The pitch of a (single) thread is typically in the range of 0.5-5 mm, particularly preferably in the range of 1.5-3 mm, and of two threads relative to one thread in the range of 1-7 mm, particularly preferably 2-5 mm.

[0029] The threaded region preferably has a thread pitch which extends at least 400°, preferably at least 450° or circumferentially.

[0030] Or the threaded region has two thread turns, each of these thread turns rotating by at least 200°, preferably at least 270°, the two thread turns preferably being offset by 160-200°, preferably in the range of 180°.

[0031] A further preferred embodiment is characterized in that the component with thread is subjected to further punching and / or forming operations and / or coating operations after the formation of the thread, in particular with the formation of further sections and / or rolled edges.

[0032] According to a further aspect, the present invention relates to a device for carrying out such a method. In other words, it concerns a device for producing a component with a threaded region in a stamping process from a blank with a substantially cylindrical section.

[0033] Preferably, such a device is characterized in that a thread core with a partially or completely circumferential core contour region is provided, with which the thread region can be formed in the form of at least one at least partially circumferential recess with a thread pitch by axially inserting the thread core with the partially or completely circumferential core contour region into an interior of the substantially cylindrical section of the blank.

[0034] Furthermore, a plurality of slides arranged circumferentially around the substantially cylindrical section of the blank are provided, with which the at least one at least partially circumferential recess with a thread pitch can be embossed by the plurality of slides being able to be displaced synchronously radially inwards, so that the material of the substantially cylindrical section is formed into the thread region substantially circumferentially between the core contour region of the thread core and slider contour regions provided radially on the inside of the slides.

[0035] For the synchronous movement of the slides radially inwards, a number of essentially axially arranged drive wedges with a radially inner guide surface which each widens in the closing direction of the tool is provided, at least corresponding to the number of slides, and the drive wedges are displaced in the closing direction to close the slides, wherein the radially inner guide surfaces of the drive wedges slide on radially outer slide guide surfaces which widen correspondingly in the closing direction and displace the slides synchronously radially inwards.

[0036] Last but not least, the present invention relates to a threaded component produced by such a method or in such a device, preferably in the form of a screw cap or a part thereof, or at least a portion of a container for a screw cap, preferably in the form of a dome portion for such a container, in particular a gas-tight and / or liquid-tight container.

[0037] Further embodiments are specified in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Preferred embodiments of the invention are described below with reference to the drawings, which are for illustrative purposes only and are not to be construed as limiting. In the drawings: Fig. 1 In a) a schematic axial sectional view of a cylindrical blank and in b) a schematic axial sectional view of a thread produced from it with rolled edge and connection area; Fig. 2 a perspective view of the tool in the retracted state; Fig. 3 in a) an axial sectional view of the tool at a press angle of 0° with the blank presented, and in b)-e) the sectional views according to AA to DD in a), each from above at different heights; Fig. 4 an axial sectional view of the tool at a press angle of 32°; Fig. 5 an axial sectional view of the tool at a press angle of 92°; Fig. 6 in a) an axial sectional view of the tool at a press angle of 110° and in b) the sectional view according to DD in a); Fig. 7 in a) an axial sectional view of the tool at a press angle of 110° and in b) the sectional view according to DD in a); Fig.Fig. 8 shows an axial sectional view of the tool at a press angle of 180°; Fig. 9 shows an axial sectional view of the tool at a press angle of 228°; Fig. 10 shows an axial sectional view of the tool at a press angle of 250°; Fig. 11 shows in a) an axial sectional view of the tool at a press angle of 268° and in b); the sectional view according to DD in a). DESCRIPTION OF PREFERRED EMBODIMENTS

[0039] Fig. 1 shows schematically in axial sectional views a component with thread 1 in different manufacturing phases.

[0040] In a), a possible blank 12 for the proposed process is shown. It is a simple cylindrical section with an interior space 13 and a circumferential cylindrical wall 16, so that there is an upper opening 14 with a circumferential edge, and a lower opening 15 with a circumferential edge.

[0041] This blank 12 can be formed in the proposed method to form a threaded section 2, namely into a component with a thread 1, as shown in b).

[0042] The component as shown in b) was subjected to further processing steps following the formation of the thread 2. Specifically, a rolled edge 7 with a radius r was formed at the top, i.e., an upper connection area 6. In addition, a lower connection area 5 was formed. This can also be formed before the thread 2 is stamped. The lower connection area 5 has a cylindrical flange area 6 and a circumferential bead 8 without a pitch.

[0043] It should be noted that the proposed method can also form, for example, a circumferential bead 8 without a pitch in parallel to the formation of a thread and in the same tool by appropriately forming the contact surfaces 44 on the slide 40 and on the thread core 46, provided that the thread core 46 is an expandable thread core as described above.

[0044] In this case, the threaded section 2 has a single thread pitch with a pitch g, with the thread being formed in the form of recesses 3 and intervening grooves 4 (as viewed from the outside 11). Viewed from the interior 10, the grooves 4 are recesses, and the recesses 3 appear as grooves.

[0045] The process can be used, for example, to form threads for tops (domed or conical) of flat and funnel-shaped cans according to DIN 2005, for example, combined with a plastic lid. Alternatively, it can be used to provide an element (bottom screw part) for a screw cap made of sheet metal in accordance with DIN 2032; such an element is also available in Fig. 1a ). In the following Fig. 2 - 11 The tool and the machined workpiece are shown in different representations and positions. The same reference symbols refer to the same or equivalent elements / components, and for clarity, not all reference symbols are actually shown in all figures.

[0046] Fig. 2 shows a perspective view of the closed tool. The upper block 20 of the tool and the guide rod 22 of the ejector 21 projecting upwards above it are visible. Also visible are the axially extending drive wedges 27 distributed over the circumference of the outer edge of the lower surface of the upper block 20, between which axially extending gaps 32 remain. Also visible is the lower block 51 with its surface 54 and circumferential chamfer 56. The upper block 20 is displaced in the axial direction relative to the lower block 51 as part of the tool stroke.

[0047] The thread segments 40 are driven by the drive wedges 27 via a wedge drive. The number of thread segments depends on the thread size and can be up to a maximum of 18 segments 40. The thread can also be formed in several stages, with the successive stations or thread segments being rotated at a certain angle to each other.

[0048] The individual phases of the process and the positions of the tool in the phases are shown in the Fig. 3-11 in central axial sections (each in a)) and are explained below. The rotational position of the sections is the same everywhere, namely through two opposite sliders, with the exception of the Fig. 6 and 10 , in which a position is shown which passes through the element 61, ie a pilot pin, and the section passes through two opposite columns 45.

[0049] The initial situation of the process, ie the situation for a press angle of 0°, is shown in Fig. 3 shown. The tool is open and the blank 12 is placed in the station. The ejector 21 with the plunger 22 guided in the recess 25 and the extended head section 23 with a bottom side 24 is spring-loaded. The circular slide plate 37 with a central recess 58 and a cylindrical radial circumferential surface 53 is also spring-loaded via pressure pins. The lifting plate 36 is in turn spring-loaded via pressure pins (not shown). The thread core 46 has a guide extension 48 at the bottom, which is guided in the guide recess 52 of the lower block 51. In the uppermost area of ​​the extension section 47, the contour area 49 for stamping the thread 2 is provided all around the thread core 46. The thread core 46 is closed off at the top by the upper limiting surface 50, but can also be closed off differently depending on the design. Is limited by the flange of the thread core or by the thread in the case of a thread core that needs to be turned out.

[0050] In this illustration, the blank 12 rests on the upper support surface 62 of the lifting plate 36. It is a cup-shaped blank open at the bottom with a circumferential wall 16, closed at the top by a base 34, and provided at the bottom of the opening is an outwardly projecting flange 35. The blank 12 rests with this flange on the upper support surface 62, on the axis of the tool, and essentially in such a way that the interior space 13 is aligned with the extension section 47, which, with the contour region 49, is already arranged in a central recess of the lifting plate 36.

[0051] The upper part of the tool initially comprises, from above, the aforementioned upper block 20 with the through opening 25 for the plunger 23 of the ejector 21. On the lower surface 26 of this block 20, on the outer edge and distributed over the circumference, in this case 18 drive wedges 27 are fastened. These are rod-shaped, with the outer surface 29 essentially flush with the circumferential surface of the block 20. The width of the drive wedges 27 is selected such that axial gaps 32 remain between the drive wedges 27. The upper region of each drive wedge 27 is designed as a parallel section 30, i.e. the radially inward-facing surface runs essentially parallel to the tool axis. This section 30 is not mandatory, but can serve to accommodate parts of the slide plate 37 if necessary when fully closed.Below each of the parallel areas 30 is a converging area, which has a beveled inner surface 31 radially inward. This flat surface 31 serves as a guide for controlling the slides. Each drive wedge 27 is limited at the bottom by an axial end surface 33.

[0052] The link 31 controls the slides 40, which accordingly have a corresponding bevelled outer surface 41 that slides over the link 31 when the tool is closed.

[0053] Each slide 40 is in turn designed as a circular segment element corresponding to a respective drive wedge 27, which has the aforementioned slotted guide 41 on the radial outside. On the radial inside, each slide 40 has a contour region 44, which is formed in segments corresponding to the contour 49. When the slides 40 are fully pushed together, the individual segments of this contour region 44 form a closed circumferential surface. In the open state (slide on the outside), gaps 45 remain between the individual regions 44, again extending radially and axially over the height of the slides.

[0054] In the illustrated embodiment, the guide surfaces 41 are designed as flat planes. This means that the slides are displaced inwards at a constant speed when the stroke speed is constant, and outwards when opening. To enable different displacement speeds of the slides in different machining phases, either the stroke speed can be regulated or, which is particularly advantageous in the present design, it is possible to design the guide surfaces 41 as curved planes as a control line. Areas with a low displacement speed of the slides then have a smaller angle to the main axis of the tool, and areas with a high displacement speed have a larger angle to the main axis of the tool.The device therefore makes it possible, for example, in a machining phase where problems arise at high slide speed (e.g., cracks, deformations, etc.), to selectively reduce the speed for this machining phase by designing the guide surface. For example, in the final phase of thread formation, the angle of the guide surface 41 to the main axis can be reduced, resulting in a lower radial speed of the slide during this final phase.

[0055] The slides 40 are mounted on a retaining plate 39, or better, between the slide plate 37 and the retaining plate 39, for radial displacement and are biased outward by return springs 38. The return springs 38 are in turn mounted in the slide plate 37, which is arranged above the slides 40, and the slides 40 slide with their sliding surface 42 on the underside of this slide plate 37. The slides 40 are captured in the axial direction between the retaining plate 39 and the slide plate 37. The return springs 38 are each received in a radially extending recess 60 in the slide plate 37. The return springs 38 are each depicted in a hypothetically fully compressed form; the visible cavity 59 in the figures is merely provided for illustrative purposes. The return springs 38 are in fact each braced against a step 43 in the respective slide 40 and fill the corresponding cavity.

[0056] The cuts in the Fig. 3 b-e ) show sections on the planes AA - DD in Fig. 3 a) , and illustrate how, on the various levels, the drive wedges 27 are arranged in a regular manner distributed over the circumference under load in the gaps 32 (see in particular b)), how the spatial arrangement is given at the level of the slide plate 37 (see in particular c)), how the slides 40 are braced radially outwards relative to the slide plate 37 via the return springs 38 (see in particular d)), and how, at the level of the contour area 44 of the slides 40, in the open position, the cavity 64 is not arranged adjacently, but rather the aforementioned gaps 45 remain between them, i.e. the cavity 64 is open and suitable for the introduction of the blank 12. The slides 40 are captured in the axial direction between the slide plate 37 and the wedge-shaped holding plates 39 arranged circumferentially between the slides 40, via lateral extensions of the slides 40.The slide plate 37 has a circumferential row of screw clearance holes 55. The retaining plates 39 have corresponding through holes with internal threads. The entire assembly is screwed together.

[0057] Fig. 4 shows the tool in the state when the ejector 21 has moved with its lower surface 24 onto the bottom 34 of the blank, which corresponds to a press angle of 32°. Here, too, the slide plate 37 and the lifting plate 36 are spring-loaded via pressure pins. The threaded core 46 is fixed in height and already adjusted in relation to the rotation position so that the contour surface 49 corresponds to the corresponding contour surfaces 45 of the slide 40 in the closed state.

[0058] In Fig. 5 The tool is pushed further together; specifically, the blank 12 is now retracted into the cavity 64, i.e., to the height of the slides in the upper tool; the ejector 21 has been retracted into the upper part of the tool for this purpose. Specifically, the slide plate 37, or rather the holding plate 39, moves toward the lifting plate 36. The thread core 46 remains unchanged with respect to the lower block 51. The press angle here corresponds to 92°.

[0059] In Fig. 6 The tool is shown at a press angle of 110°. The ejector 21 has moved onto the blank 12. Because the slide plate 37 has moved onto the lifting plate 36, the blank 12 is clamped with its flange 35 between the holding plate and the surface 62 of the lifting plate 36. The slide plate 37 moves onto the pilot pin 61 of the lower block 51.

[0060] In Fig. 7 The tool is shown at a press angle of 132°. The ejector 21 has moved onto the blank 12. The blank 12 is thus clamped with its flange 35 on the surface 62 because the slide plate 37 has moved onto the lifting plate 36. The slide plate moves onto the pilot pin 61. In this phase, the slides 40 begin to be moved radially inwards due to the sliding of the surface 41 on the corresponding surface 31 of the corresponding guide wedge 27 until the thread 2 is stamped in the cylindrical section of the blank 12. The lifting plate 36 and ejector 21 support this process by upsetting, i.e. the blank is pressed together in the axial direction during this phase. As can be seen from the section according to b), the tool is not yet completely closed, ie there are still very small gaps 45 remaining at the front near the contour surfaces 44.

[0061] When presented in Fig. 8 The slides 40 are moved completely inward, closing the tool and completely stamping thread 2. The press angle here is 180°, and the tool is at bottom dead center. From now on, the tool is opened again. To make this possible, the thread core 46, which is now trapped in component 1, must either be contracted radially for its removal or, as shown here, be turned out of thread 2 by rotation.

[0062] When switching to the display according to Fig. 9 (a press angle of 228° is shown specifically), the thread core 46 is now rotated accordingly, typically starting at a press angle of 185°, with a pitch of 2 and guided out of the component. During this phase, the component is still clamped between the slide plate 37 and the lifting plate 36. The ejector 21 springs out and the lifting plate 36 also springs out. Each slide 40 springs back and the slide plate 37 springs out. In the illustration in Fig. 10 The tool is opened even further at a press angle of 250°. At this point, the thread core 46 is completely turned out, and the ejector 21 extends.

[0063] In Fig. 11 Finally, the tool is shown at a press angle of 268°. The clamping of part 1 between slide plate 37 and lift plate 36 is released here. After further opening, the finished component 1 can now be transferred to the next processing stage, for example, in a transfer station. Lateral grippers can be used for this purpose (the same applies to feeding the blank in this station).

[0064] The thread is made as shown in the Fig. 3-11 shown and described. The threaded core 46 is fixed and oriented in a threaded bushing.

[0065] The drive can be pneumatic or servo-driven, for example. With a pneumatic drive, the thread would be formed with a ratio of approximately 1 to 6, and the rotary cylinder would move to the index (stop).

[0066] The thread core 46 has the profile of the thread to be rolled and another thread with the same pitch on the shaft. To allow the core to be aligned in height and position, a threaded nut with shims is positioned in block 51. These can be used to adjust the radial position of the thread. The drive is provided by a rotary cylinder, which drives the core with a gear ratio (half a turn of the rotary cylinder = 3 turns of the core). The drive is mounted on the core in a floating bearing.

[0067] This means that forming the thread up to 180° (finishing the thread) works without any problems. LIST OF REFERENCE SYMBOLS

[0068] 1Component with thread 2Threaded area of ​​1 3Circumferential recess of 2 with pitch, groove 4Circumferential elevation of 2 with pitch, rib 5First connection area 6Second connection area 7Rolled edge 8Circumferential bead of 5 without pitch 9Cylindrical flange area of ​​5 10Interior of 1 11Radial outer area of ​​1 12Blank 13Interior of 12 14Upper opening of 12, circumferential edge 15Lower opening of 12, circumferential edge 16Cylindrical circumferential wall of 12 17Radial outer area of ​​12 20Block 21Ejector 22Guide rod of 21 23Head part of 21 24Underside of 21 25Through opening in 20 for 22 26Underside of 20 27Drive key 28Upper fastening area of ​​28 on 20 29Outer surface of 27 30Parallel section of 27 31Chamfered inside surface of 27 32Axial gaps between 27 33Axial end surface of 27 34Bottom of 12 35Radial flange of 12 36Lifting plate 37Slide plate 38Return spring for slide 39Retaining plate for slide 40Slider 41Beveled outer surface of 40 42Sliding surface from 40 to 37 43Step in 42 for 38 44Contour area of ​​41 45Axial gaps between 40 46Thread core 47Extension section of 46 48Guide extension of 46 49Contour area of ​​46 50Upper boundary surface of 46 51Lower block 52Guide recess in 51 for 46 53Cylindrical radial circumferential surface of 37 54Surface of block 51 55Screw clearance hole 55Through holes with internal thread 56Chamfer of block 51 58Central recess in 37 59Spring chamber 60Recess in 37 for 38 61Pilot pin 62Upper contact surface of 36 63Closing direction of the tool 64Cavity of the tool d 1 Outer diameter of thread d 2 Outer diameter of 5 / 8 d 3 Inner diameter of 5 d 4 Inner diameter of 7 d 5 Diameter of the blank fThread depth gPitch height h 1 axial height of 8 h 2 axial height of 9 h 3 axial height of 12 h 4 axial height of 7

Claims

1. Method for producing a component (1) with a threaded area (2) in a stamping process from a blank (12) with a substantially cylindrical section (16), characterized in thatthe threaded region (2) is formed in the form of at least one at least partially circumferential recess (3) with a thread pitch (g) by axially introducing a thread core (46) with a partially or completely circumferential core contour region (49) into an interior space (13) of the substantially cylindrical section (16) of the blank (12), and the at least one at least partially circumferential recess (3) with a thread pitch (g) is formed by a plurality of slides (40) arranged circumferentially around the substantially cylindrical section (16) of the blank (12) by synchronously displacing the plurality of slides (40) radially inward, so that the material of the substantially cylindrical section (16) is formed into the threaded region (2) substantially circumferentially between the core contour region (49) of the thread core (46) and slider contour regions (44) provided radially on the inside of the slides (40),wherein, for the synchronous movement of the slides (40) radially inward, a number of substantially axially arranged drive wedges (27) is provided, each having a radially inner guide surface (31) which widens in the closing direction (63) of the tool, corresponding to at least the number of slides (40), and the drive wedges (27) are displaced in the closing direction (63) to close the slides (40), wherein the radially inner guide surfaces (31) of the drive wedges (27) slide on radially outer slide guide surfaces (41) which widen correspondingly in the closing direction (63) and displace the slides (40) synchronously radially inward.

2. Method according to claim 1, characterized in thatdistributed over the circulation, fewer than 20 slides (40) and a corresponding number of fewer than 20 drive wedges (27) are provided, wherein preferably in the range of 10-19, particularly preferably in the range of 15-18 slides (40) and a corresponding number of drive wedges (27) are provided.

3. Method according to one of the preceding claims, characterized in that the drive wedges (27) are fastened to a common block (20), this fastening preferably allowing individual adjustment of the drive wedges (27).

4. Method according to one of the preceding claims, characterized in thatthe drive wedges (27) are fastened to a block (20) which is axially offset from the cavity (64) of the tool and which has the drive wedges (27) as rod-shaped elements directed in the axial direction towards the cavity (64), which are distributed over the circumference with intermediate spaces (32), and whose respective inner link surface (31) is preferably designed as a flat plane.

5. Method according to one of the preceding claims, characterized in that the slider link surfaces (41) are designed as flat planes, or as a curved plane for the processing phase-dependent speed control.

6. Method according to one of the preceding claims, characterized in that the substantially cylindrical portion (16) of the blank (12) is pressed in the axial direction during the forming of the threaded portion (2).

7. Method according to one of the preceding claims, characterized in thateither the thread core (46) is designed as a rigid element that is turned out of the interior (10) of the threaded component (1) when the tool is opened, or the thread core (46) is designed as a radially expandable element that, in the expanded state, provides a substantially continuous, circumferential core contour region (49) for the stamping process of the thread region (2), and that can be contracted at least in the core contour region (49) into a state with a smaller circumference, and in this contracted state is moved without rotation in the axial direction when the tool is opened from the interior (10) of the threaded component (1), wherein the expandable element preferably has at least three wedge-shaped circular segment elements. DE102011011784A1 8. Method according to one of the preceding claims, characterized in thatthe threaded component (1) and / or the blank (12) contains metal or consists of metal, preferably aluminum, copper, iron, including their alloys, in the case of iron in particular steel, wherein the metal preferably has a thickness in the range of 80 µm - 1 mm, preferably in the range of 150 - 500 µm, particularly preferably in the range of 200 - 400 µm, and / or wherein the metal has a paint or coating on at least one or both sides.

9. Method according to one of the preceding claims, characterized in thatthe blank (12) is provided for the method in a punching process and / or forming process and / or coating process, and / or that the blank (12) has a central through-opening or has a base (34) on one side and / or that the blank (12) has a circumferential flange (35) at one or both axial ends, wherein the flange is preferably oriented radially inwards or radially outwards, in particular at an angle of 80-100° to the axis of symmetry of the blank, and / or that the blank is a cup-shaped blank.

10. Method according to one of the preceding claims, characterized in that the threaded component (1) is a screw cap or a part thereof, or at least a section of a container for a screw cap, preferably a dome section for such a container, in particular a gas-tight and / or liquid-tight container.

11. Method according to one of the preceding claims, characterized in that the outer diameter (d1) of the thread is in the range of 5-100 mm, in particular in the range of 7-50 mm or in the range of 10-30 mm, and / or that the thread depth (f) in the thread region (2) is in the range of 0.3-5 mm, preferably in the range of 1-3 mm, and / or that the pitch (g) for one thread turn is in the range of 0.5-5 mm, in particular preferably in the range of 1.5-3 mm, and for two thread turns based on one turn is in the range of 1-7 mm, in particular preferably 2-5 mm.

12. Method according to one of the preceding claims, characterized in thatthe threaded region (2) has one thread turn, which extends by at least 400°, preferably at least 450°, or that the threaded region (2) has two thread turns, each of these thread turns extending by at least 200°, preferably at least 270°, the two thread turns preferably being offset by 160-200°, preferably in the range of 180°.

13. Method according to one of the preceding claims, characterized in that the threaded component is subjected to further punching and / or forming operations and / or coating operations after the thread has been formed, in particular with the formation of further sections and / or rolled edges.

14. Device for carrying out a method according to one of the preceding claims for producing a component (1) with a threaded area (2) in a stamping process from a blank (12) with a substantially cylindrical section (16), characterized in thata thread core (46) with a partially or completely circumferential core contour region (49) is provided, with which the thread region (2) can be formed in the form of at least one at least partially circumferential recess (3) with a thread pitch (g) by axially inserting the thread core (46) with the partially or completely circumferential core contour region (49) into an interior space (13) of the substantially cylindrical section (16) of the blank (12), and a plurality of sliders (40) arranged circumferentially around the substantially cylindrical section (16) of the blank (12) are provided, with which the at least one at least partially circumferential recess (3) with a thread pitch (g) can be stamped by synchronously displacing the plurality of sliders (40) radially inwards,such that the material of the essentially cylindrical section (16) is formed into the threaded section (2) essentially circumferentially between the core contour region (49) of the thread core (46) and slide contour regions (44) provided radially on the inside of the slides (40), wherein for the synchronous movement of the slides (40) radially inward, a number of essentially axially arranged drive wedges (27) is provided, each with a radially inner guide surface (31) widening in the closing direction (63) of the tool, which corresponds at least to the number of slides (40), and the drive wedges (27) are displaced in the closing direction (63) to close the slides (40), wherein the radially inner guide surfaces (31) of the drive wedges (27) slide on radially outer slide guide surfaces (41) widening correspondingly in the closing direction (63), and the slides (40) synchronously shift radially inwards, 15. Component with thread (1) produced by a method according to one of the preceding claims or in a device according to claim 14, preferably in the form of a screw cap or a part thereof, or at least a section of a container for a screw cap, preferably in the form of a dome section for such a container, in particular a gas- and / or liquid-tight container.

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