EP2255903B1 - Head buckling device - Google Patents

Abstract

The device has a header die (17) moving axially against a workpiece from a rest position. Clamping jaws (32, 33) are pressed radially against the workpiece by a clamping segment (28). The die carries a forming tool (24) for compressing the workpiece. The die is axially pressed against a head, which is projected from the clamping jaws, of the workpiece by an opening provided in a locking plate (18) during extension of the die. The die is moved completely out of the opening with the forming tool in the rest position of the die.

Description

The invention relates to a head compression device for elongate workpieces, such as rods, tubes, wire or the like, and in particular relates to a cold heading device.

Such Kopfstauchvorrichtungen serve to the ends of rod-shaped workpieces, so tube or rod ends, upsetting, the tube wall or the rod end is thickened, sometimes additionally provided in the course of the elongated workpiece by compression also one or more other local thickening (flare) should be.

A Kopfstauchvorrichtung with an operable in the axial direction of the device clamping device is from the US-A-2464510 known.

A hydraulic cold heading compression device is used in the CH-PS 477 929 described, however, the device known therefrom has a very large and complicated overall structure, in which the use of assembly tools required for performing a tool change and the tool change itself is relatively tedious.

From the DE 2629796 C is a hydraulic Kopfstauchvorrichtung for pipes and rods is known in which, however, a heater is used for heating the workpiece to be formed and thus takes place forming with heating. The heating takes place via two single-coil induction coils, which allow to achieve a well-defined heating zone with predetermined temperature gradient, wherein the front end of the part to be upset is heated more than the rest of the heating zone. This known Kopfstauchvorrichtung is complicated due to the built-in heater in construction, operation and a tool change.

Another known Kaltkopfstauchvorrichtung is the FR 2 231 449 A removable. This hydraulic device works with several forming areas, which, however, results in an overall very large unit building. A tool change, if it is to take place, relatively expensive.

Proceeding from this, the object of the invention is to provide a cold heading device which allows improved operability, a reduction of set-up time and a simple and rapid replacement of the jaws without the need to use special assembly tools.

This is achieved with a Kopfstauchvorrichtung for elongated workpieces, such as rods, tubes, wire or the like., Which has a hydraulically actuated clamping device and a retracted from a rest position axially movable against the workpiece upsetting die, wherein the clamping device comprises a housing with a hydraulically in Axial direction of the workpiece from a starting position into a clamping position and vice versa displaceable sliding body, in which at least two evenly around the workpiece ordered clamping segments are inserted, which rest on its side facing the stamper against an inserted into the housing and there fixable locking plate by a Displacement of the sliding body in its clamping position are radially movable against the workpiece and each record at least one jaw which is pressed by the holding him clamping element radially against the workpiece to its jamming, further wherein the upsetting punch on the extension side carries a forming tool for upsetting the workpiece, with which it is pressed when extending through an opening provided in the locking plate against the axially protruding from the jaws head of the workpiece, and in its retracted rest position with his forming tool completely the opening of Verriegetungsptatte has moved out.

The cold heading compression device according to the invention is easy to use, does not require much space and in her a tool change is particularly easy, simple and quick to carry out, without a special assembly tool.

For tool change, it is only necessary in the inventive head thrust device pushed into the housing locking plate after lifting their fixation pushed out of the housing, then from this back of the housing forth the clamping segments with the jaws contained in them, the previously on the locking plate, individually and can be easily pulled out because they are even inserted in the surrounding sliding body. If a clamping element taken out, and each jaw, which is included in it, removed and a new jaws (with a new shape for a changed workpiece) can be easily inserted. Subsequently, the two clamping elements are inserted with inserted (new) jaws in the housing and the existing sliding body there again or inserted and then by re-insertion of the Locking plate in the housing (and then fixing the same) completed the tool change process. After all relevant here for the replacement of the tools relevant parts can be pulled out of the housing at a remote locking plate, as they are all only inserted or plugged in and there are nowhere fixed, the tool change is quick and easy to carry out. Accordingly, the set-up time is significantly reduced in the head-ups device according to the invention over the known devices, because the replacement of the jaws can be done quickly. In addition, with an exchange of the jaws and no intervention in the hydraulic systems of the device according to the invention is required.

Finally, the head compression device according to the invention also builds relatively space-saving due to the arrangement of the individual parts of the clamping device inside the housing, wherein in the invention, the axial movement of the sliding body in a radial clamping movement of the clamping segments reshaped and thereby an arrangement of the latter space-saving within the sliding body is possible.

In the invention, it has proved to be particularly advantageous if two clamping segments are provided and in each of them two axially arranged one behind the other in a corresponding receptacle jaws, wherein, again preferred, the jaws arranged to form an axial gap between them, axially against each other attached and pressed axially apart by at least one compression spring between them. In this embodiment, there is the possibility that a thickening is formed when upsetting the workpiece not only at the head, but also in the course of its length in the area between the two jaws when upsetting. This happens because when hitting the compression punch on the head of the workpiece, the two behind the head the workpiece detecting jaws of both clamping elements under the influence of axial compression force on upsetting the workpiece axially within their recordings in the respective sliding body in the direction of the second remaining there Clamping jaws can slide under reduction of the gap between them, which then due to the clamping effect of the second jaws clamped by them workpiece can not move axially, so that as a result of the reduction of the gap and the firm clamping of the workpiece between the first jaws Within the space existing material of the workpiece is radially thickened until the first jaws come with their sliding movement to a halt. It is also possible to provide on the side of the first jaws, which faces the respectively downstream second jaw, an axial recess in each first jaw, which determines the compressed material shape of the portion between the two jaws, so that during the upsetting process, the first jaws can be pushed to rest against the second jaws and thereby forms the compressed thickening of the material within this recess in the first jaws.

A particularly simple construction of the device according to the invention is also obtained when the upsetting die-actuating hydraulic cylinder is mounted on the side facing away from the housing of the device of a closure plate, which in turn, viewed in the direction of movement of the compression punch, is arranged at a distance from the locking plate. This leads to the great advantage that in a tool change after removing the locking plate from the housing of the then given and existing access space for replacing the clamping elements, etc. is relatively large. Particularly preferably, the distance between the end plate and locking plate is chosen so that it is greater than the axial length of each clamping segment. This allows that after removing the locking plate each clamping element parallel to its position in the housing can be taken out of this without the need for a lateral tilting of the clamping element in the course of pushing out.

To implement the axial displacement movement of the sliding body in the housing in a radial clamping movement of the clamping elements, it is advantageous if each clamping element has on its upper side and on its underside two guide rails lying parallel to each other, each aligned at an acute angle to the direction of displacement of the sliding body and their each positively and displaceably engage in a trained and assigned in sliding body guide groove. As a result, a very space-saving implementation of the axial movement of the sliding body in a radial clamping movement of the clamping elements is possible.

Advantageously, the housing is provided on its front side opposite the locking plate front with a lid having a central opening through which the workpiece can be inserted into the housing, wherein the sliding body in its initial position with a stop surface attached to it against this cover rests. In this case, a guide and centering device for the workpiece is preferably mounted on the side facing away from the housing of the lid. This guiding and centering device advantageously comprises two attached to the opening of the lid pivoting lever with guide jaws, which are pivotable from an unfolded rest position in an applied against the workpiece centering (and vice versa), wherein, again preferred, both pivoting lever with the Sliding body are pivotally connected, such that they occupy their unfolded rest position when the sliding body is in its initial position, on the other hand be transferred in its clamping position in movement of the sliding body in its folded centering position (and vice versa). This ensures that the sliding body is in its starting position when a new workpiece is introduced by the guiding and centering device in the housing, the movement of the sliding body in its clamping position on the outside of the lid of the two pivoting levers by their folded centering position centered and held.

Another preferred way of actuating the two pivoting lever but can also be achieved in that they are both independently of the position of the sliding body pivotally, for this purpose z. B. a separate pivot drive can be provided. This allows the workpiece, already inserted into the housing, to be already centered and held by both pivoting levers at a time when the sliding body has not yet begun its axial displacement.

It is again advantageous in a head compression device according to the invention, when the entire device is mounted on a separate frame and can be moved on this in the direction of displacement of the compression punch. This axis allows a particularly great flexibility in the use of the compression device by z. B. between a bending machine and the head compression device according to the invention a greater clearance can be created. At the same time it is prevented that the workpiece must be positioned in the axial direction before and after upsetting or axially relative to the compression device must be moved. This proves to be particularly unfavorable, if endless coil material is processed on a bending machine, which should basically not be moved backward as possible. The workpiece can thus be theoretically positioned in a certain position in front of the retracted head compression device according to the invention, which is then moved forward via this drive, the workpiece is formed and then moved back again. This even allows the feeding of the workpieces by means of a feed device moved transversely to the axial direction of the workpieces (for example a rotating robot with processing units mounted in a circle around it, or a moving feeder with a plurality of processing stations or the like mounted parallel to one another).

Fig. 1

eine perspektivische Gesamtansicht einer erfindungsgemäßen Kopfstauchvorrichtung;

Fig. 2

eine vergrößerte perspektivische Darstellung der Staucheinheit aus Fig. 1;

Fig. 3

einen Vertikalschnitt durch die Staucheinheit gemäß Fig. 2, und zwar mit eingefahrenem Stauchstempel und Position des Schiebekörpers in seiner Ausgangsstellung;

Fig. 4

einen Schnitt in horizontaler Lage durch die Staucheinheit gemäß Fig. 2, wobei hier der Stauchstempel sich in seiner ausgefahrenen Stauchposition und das Schiebeteil in seiner Klemmstellung befindet;

Fig. 5

eine vergrößerte Detaildarstellung eines Ausschnitts aus der Stauchvorrichtung gemäß Fig. 2 zur Darstellung der Verhältnisse bei einem Werkzeugwechsel, und

Fig. 6

eine vergrößerte Perspektivdarstellung eines Spannsegmentes mit zwei eingelegten Klemmbacken.

The invention will now be explained in more detail by way of example with reference to the drawings in principle. Show it:

Fig. 1

an overall perspective view of a head compression device according to the invention;

Fig. 2

an enlarged perspective view of the upsetting unit Fig. 1 ;

Fig. 3

a vertical section through the compression unit according to Fig. 2 , with retracted upsetting punch and position of the sliding body in its initial position;

Fig. 4

a section in a horizontal position through the compression unit according to Fig. 2 , Here, the upsetting punch is in its extended compression position and the sliding part in its clamping position;

Fig. 5

an enlarged detail of a section of the compression device according to Fig. 2 to illustrate the conditions in a tool change, and

Fig. 6

an enlarged perspective view of a clamping segment with two inserted jaws.

In Fig. 1 is a perspective view of a Kopfstauchvorrichtung 1, consisting essentially of two main parts, namely a compression unit 2 and a hydraulic unit 3. The latter is a per se known device which serves to the required pressures (about Verstokkräfte up to 600 kN) in provide existing system.

The compression unit 2 and the hydraulic unit 3 are mounted on a frame 4, which in turn can be moved or offset along a bottom plate 5, in the direction a according to the orientation of the longitudinal axis of the workpieces to be machined as well as the longitudinal axis of the compression unit 2 along guides. 6 which are mounted on the bottom plate 5.

In Fig. 2 is shown a perspective but enlarged view of the upsetting unit 2, which is arranged on the frame 4, the in Fig. 2 only shown in principle in the form of a common base plate.

According to Fig. 2 the upsetting unit 2 sits on the frame 4 on two parallel longitudinal rails 7, along which they can be moved by a motor 8 and a spindle drive 9 again in the direction of a . This additional compared to conventional devices traverse axis allows a great deal of flexibility in using the compression unit 2. This also prevents the workpiece in the axial direction before and after upsetting extra positioned or axially relative to the upsetting unit 2 would have to be moved, which is particularly unfavorable is when endless coil material is processed on a bending machine, which in principle should not be moved backwards as far as possible. The workpiece can thus be positioned in a specific position in front of the upsetting unit 2 driven back on the longitudinal rails 7, this then being moved forward, the workpiece up and then again can go back. Thus, the supply of workpieces by a transversely to the axial direction of the workpieces moving feeder (such as a rotating robot with circular mounted around these processing units, or a moving feeder with several parallel processing stations mounted o. Ä.).

Out Fig. 2 Further details of the compression unit 2 are removable:

It initially comprises a housing 10 which has a cover 11 and a guiding and centering unit 12 on its front side (facing the workpiece supply). On the opposite (rear) side of the housing 10 via connecting webs 13, which provide a free space 14, connected to a closure plate 15. On the side facing away from the housing 10 of the end plate 15, a hydraulic cylinder 16 is attached to this, the punch 17 forms the upsetting die and carries a forming tool 24 at its ausfahrseitigem end.

Furthermore, a locking plate 18 in the housing 10 can be inserted, which, as particularly well from the illustration of Fig. 5 Removable, has a central bore 19 through which the forming tool 24 can be pressed against the lying behind the head of the workpiece for upsetting during the extension of the compression punch 17.

How out Fig. 1 can be seen, both the connecting webs 13 and the end plate 15 are covered up, as well as the hydraulic cylinder 16 and the movability of the upsetting unit 2 along the longitudinal rails 7 causing motor 8 and the spindle drive 9 by means of an above it in the assembled, ready-to-use state Protected cover protected from the outside

Fig. 3 shows the compression unit 2 in a vertical section (perpendicular to the bottom plate 5) along the longitudinal center axis 21 of the compression unit 2. Shown here is the open position of the guiding and centering unit 12, ie the position in which workpieces 20 can be introduced. In contrast, shows Fig. 4 3 a horizontal section of the compression unit 2, wherein the sectional plane is parallel to the base plate 5 and through the longitudinal central axis 21 (FIG. Fig. 2 ) of the upsetting unit 2 extends. In Fig. 4 is now the closed position of the tools, so the compression position shown.

At its rear end, ie the end of the punch 17 facing the housing 10 is provided with guide angles 22 ( Fig. 4 ), with which complementarily shaped guide flanges 23 ( Fig. 3 ) are slidably engaged on the lock plate 18, the direction of displacement in the Fig. 4 and 5 each indicated by the arrow b.

Like the presentation Fig. 2 shows, the locking plate 18 is arranged so that it can be inserted laterally into the housing 10. However, for lateral removal of the locking plate 18 of the upsetting die 17 of the hydraulic cylinder 16 must be brought into a fully retracted rest position, in softened at its extension end to him attached forming tool 24 is completely pulled out of the bore 19 in the locking plate 18. This rest position of the compression punch 17, which must be taken only when the locking plate 18 is removed from the housing 10, is in the illustration of Fig. 5 but not in the cuts of the FIGS. 3 and 4 , shown.

In the housing 10, an axially hydraulically movable sliding body 26 is further mounted, which from a starting position, the in Fig. 3 is shown and in which it rests with an annular circumferential, radial abutment surface 27 on the lid 11, in an in Fig. 4 shown clamping position is movable.

Inside the sliding body 26, two clamping segments 28 are used. In the housing 10, a bore 29 is further attached, by means of which a pressure connection 43 (cf. Fig. 5 ) Pressure fluid for axial displacement of the sliding body in the housing 10 can be introduced.

In this slide body 26 are oblique, ie obliquely to the longitudinal central axis 21 of the upsetting unit 2 extending guideways 30 are provided with correspondingly inclined guide rails 31 which are formed on the two clamping segments 28 respectively on the upper and lower sides are in positive engagement and can slide along these guideways 30. In this way, an axial movement of the sliding body 26 in direction a via the guide tracks 30 and the guide strips 31 engaging in them is converted into a radial movement (direction b ) of the clamping segments 28.

The guide flanges 23 of the locking plate 18 are also available with paragraphs 25 (FIG. Fig. 5 ), which are attached to the two clamping segments 28, respectively at the front and at the top and bottom, whereby it is achieved that a displacement of the clamping segments 28 side (ie in the direction b ) and thus a bracing of the two clamping segments 28 supplied Workpiece 20 is possible, however, an axial displacement of the clamping segments 28 (in the direction a ) can not be done.

As the Fig. 5 and especially the Fig. 6 , in which such a clamping segment 28 is shown in enlargement, can be seen in this two jaws 32, 33 are received, each jaw 32 and 33 fitted on guides 34 and then inserted into a corresponding receiving groove of the clamping element 28. In the illustrated embodiment, the length of this receiving groove is slightly larger than the total length of the jaws 32 and 33 together. This results in that after complete insertion of the front jaw 32 between this and the other jaws 33, an axial spacing A remains. The second jaw 33 is prevented by means of a retaining strip 35 axially slipping out of the receiving groove.

The distance A between the two jaws 32, 33 is aufrechtefialten means of a (not shown in the figures) compression spring, which engages with its two ends each in a pot bore in the facing end faces of the two jaws 32 and 33 and these always in their axially biased position biased.

Each clamping segment 28 and its clamping jaws 32 and 33 each have a groove 36 for receiving the workpiece 20, wherein the profile shape of the groove 36 in the jaws 32 and 33 is designed so that in the clamping position of the sliding body 26 when both clamping segments 28 against the workpiece 20 are pressed radially, the largest possible clamping force can be applied to this.

At this point it should be mentioned that instead of two clamping jaws 32, 33, of course, only one clamping jaw can be used, for example, if only the workpiece end 41 (FIG. Fig. 3 ) reshaped by the upsetting die 17 and otherwise no additional flare must be made over the length of the workpiece 20 away.

The jaws 32 and 33 are designed so that they can be used on both sides, d. H. if you take them out of the receiving groove of a clamping segment 28 and rotates 180 ° about its longitudinal axis, they can then be used equally at the other clamping segment 28. This can be achieved that with a jaws 32 and 33 either achieved a double life or different workpiece diameter can be edited.

From the representation of Fig. 2 and in particular the Fig. 4 also the function of the guiding and centering device 12 becomes clear:

On the lid 11, two L-shaped angle 37 are mounted opposite each other by 180 °. Further, two levers 38 with guide jaws 39 are pivotally mounted on the sliding body 26. The levers 38 are connected to each other via a (not shown in the figures) tension spring so that they are under the spring bias in a radially outwardly pivoted away position (see. Fig. 2 and Fig. 3 ).

In an axial displacement of the sliding body 26 from its initial position ( Fig. 3 ) in its clamping position ( Fig. 4 ) the levers 38 slide on the angles 37 and are thereby closed. At the same time, the workpiece 20 is centered in the upsetting device 2 before it is fixed and clamped by the clamping jaws 32 and 33 for the upsetting operation.

However, it is also possible to replace the coupled with the axial movement of the sliding body 26 closing movement of the guide and centering device 12, as shown in the figures, by another arrangement in which the closing movement of the lever 38 regardless of the movement of the Slide body 26 and can be controlled directly. As a result, the workpiece 20 can be centered by the guiding and centering device 12 even before the closing movement of the clamping segments 28 begins.

The compression module 2 may also be additionally equipped with a lubrication system, which prevents the risk of "eating" on the tools, which is not shown in the figures.

Also measuring systems can be provided on the compression device 2, which are also not shown in the figures and z. B. detect the stroke of the upsetting punch 17 or pressing and / or clamping forces to control the compression device 2 according to and regulate.

In the presentation after Fig. 5 In addition, a failure slot 40 is provided in the housing 10 below the end deformation, whereby workpiece or tool splitter can easily fall out of the housing 10 and the upsetting unit 2, so that thereby a failure of the device can be prevented by waste.

With the upsetting unit 2 shown, simple processing of the ends of the workpieces 20, but also combined processing of both the end, as well as additionally the production of flanging can be performed.

The work of the Kopfstauchvorrichtung 1 will now be based on the 3 and 4 are explained below:

A workpiece 20 is positioned in front of the upsetting unit 2. By the movement of the upsetting unit 2 or also of the workpiece 20 in the axial direction a , the workpiece 20 is introduced into the upsetting unit. The sliding body 26 is hydraulically moved out of its rest position in the axial direction a and includes first the guiding and centering unit 12 and then the clamping segments 28, which clamp the workpiece 20 above the jaws 32 and 33 and fix. Thereafter, the cylinder 16 is activated and the upsetting die 17 with the forming tool 24 moves against the second jaw 33 and on the protruding end 41 of the workpiece 20 and moves both in the direction a . In this case, the second jaw 33 slides in its receiving groove in the direction against the other jaws 32 out, at the same time with this movement, the workpiece end 41 corresponding to the mold 38 formed in forming tool 24 and a flange 42 between the two jaws 32 and 33 is generated.

By returning the upsetting punch 17 and the sliding body 26, each in their starting position, the now deformed workpiece 20 is released again. At the same time, the two clamping jaws 32, 33 are again axially separated from one another by the distance A , under the action of the compression spring acting axially between them.

For conversion of the compression device 2 is on the enlarged perspective view of Fig. 5 referenced, which shows the area between the terminal plate 15 and the housing 10 easily recognizable.

In the position of Fig. 5 First, the compression punch 17 is spent in a fully retracted initial position, so that the forming tool 24 is no longer in the bore 19 in the end plate 15.

In the locking plate 18, which is fixed in its inserted into the housing 10 position above a device (not shown) in the lateral direction, the fixation is released and the locking plate 18 laterally removed (in the direction b ) . This state shows Fig. 5 ,

Now also the clamping segments 28 can be pulled out in the directions c ₁ and c ₂ from the sliding body 26 and then without any further tools, the jaws 32 and 33 are replaced.

It consists, how Fig. 5 shows sufficient space to B. to attach a new forming tool 24 to the upsetting die 17 can.

Claims (12)

1. Head buckling device (1) for longitudinal workpieces (20) such as rods, tubes, wires or similar, with a hydraulically activated clamping device (26, 28, 32, 33) and a punch (17) that from a retracted rest position can move axially against the workpiece (20), wherein the clamping device comprises a housing (10) with a sliding body (26) which is hydraulically displaceable in the axial direction of the workpiece (20) from a starting position into a clamping position and vice versa, and in which are inserted at least two clamping segments (28) which are evenly arranged about the workpiece (20) and on their side facing the punch (17) lie against a locking plate (18) inserted in and fixable in the housing (10), and which can be moved by displacing the sliding body (26) into its clamping position radially against the workpiece (20) and which each hold at least one clamping jaw (32, 33) that can be pressed by the clamping segment (28) holding it radially against the workpiece (20) to clamp it, wherein furthermore the punch (17) on the extension side carries a forming tool (24) for buckling the workpiece (20) with which on extension it can be pressed through an opening (19) provided in the locking plate (18) against the head (41) protruding axially from the clamping jaw (32, 33) of the workpiece (20) and its retracted position with its forming tool (24) is fully withdrawn from the opening (19) in the locking plate (18).
2. Head buckling device according to claim 1, in which two clamping segments (28) are provided, each of which comprises two clamping jaws (32, 33) arranged axially behind each other.
3. Head buckling device according to claim 2, in which the two clamping jaws (32, 33) in each clamping segment (28) are mounted axially displaceably in relation to each other to form an axial space (A) between them and are pressed axially apart by means of at least one compression spring.
4. Head buckling device according to any of claims 1 to 3, in which a hydraulic cylinder (16) activating the punch (17) is attached on the side of a closing plate (15) facing away from the housing (10), which plate viewed in the movement direction of the punch (17) is arranged at a distance from the locking plate (18).
5. Head buckling device according to claim 4, in which the distance between the closing plate (15) and the locking plate (18) is greater than the axial length of each clamping segment (28).
6. Head buckling device according to any of claims 1 to 5, in which each clamping segment (28) on its top and underside has two parallel guide strips (31) each of which runs at an acute angle to the movement direction (21) of the sliding body (26) and engages by form fit and mobile in a guide groove (30) thereof.
7. Head buckling device according to any of claims 1 to 6, in which the housing (10) on its front side opposite the locking plate (18) has a cover (11) with a central opening for passage of the workpiece (20), against which the sliding body (26) lies with a stop surface (27) in its starting position.
8. Head buckling device according to claim 7, in which a guide and centring device (12) for the workpiece (20) is arranged on the side of the cover (11) facing away from the housing (10).
9. Head buckling device according to claim 8, in which the guide and centring device (12) for the workpiece (20) comprises two swivel levers (38) with guide jaws (39) which are mounted on the opening of the cover (11) and can swivel from an open rest position into a centring position lying against the workpiece (20) and vice versa.
10. Head buckling device according to claim 9, in which the two swivel levers (38) are connected swivellably with the sliding body (26) such that they assume their open rest position when the sliding body (26) is in its starting position, and on movement of the sliding body (26) into its clamping position they are moved into their closed centring position and vice versa.
11. Head buckling device according to claim 9, in which the two swivel levers (38) are swivellable independently of the position of the sliding body (26).
12. Head buckling device according to any of claims 4 to 11, in which the entire device is mounted on a frame (4) on which it can move in the longitudinal direction (21) of the buckling unit (2).

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