EP2756891B1 - Device for bending bar-like workpieces - Google Patents

Description

The invention relates to a device for bending strand-like workpieces, such as wire, tubes, rods or the like., With a machine frame, a workpiece feed and attached to a pivoting arm, with respect to this movable bending head, wherein the pivot arm relative to the machine frame and the bending head opposite the swivel arm can be pivoted controlled in each case by at least one axis of rotation running parallel to the direction of the workpiece feed.

A device of this kind is from the EP 1 350 577 A1 and the EP 1 350 578 A1 known. In these prior art machines, however, there is the disadvantage that the bending plane does not remain constant, because the bending head must be pivoted about the two axes of rotation so that the fixed height and position of the workpiece can be approached. This has the consequence that the bending plane can not always be kept constant, z. B. aligned horizontally, which is desirable for large bending parts or unstable workpieces. In addition, with a constant horizontal bending plane held the workpiece can be supported by a support table to prevent unwanted deformation of the workpiece due to its own weight and partially faster bending and thus achieve greater unit performance, which is for example in the production of meanders of interest is. In addition, in these known machines in the case of larger workpiece diameter, the loading height (height of the workpiece in the collet above the ground) relatively large and thus operating the machine is very unfavorable.

Here, the invention is intended to remedy this situation and provide a device of the type mentioned above, in which it is possible to work with a constant bending plane, wherein different bending levels can be engaged with the workpiece without the bending plane having to be changed. In addition, the loading height should be kept very low.

According to the invention this is achieved in a device of the type mentioned in that the axis of rotation of the pivot arm is formed as an eccentric cam eccentric shaft or pin on a rotatable pivot arm, wherein the eccentric shaft or the rotatable arm about a parallel to the feed direction of the workpieces center axis on the machine frame are rotatably mounted.

In the invention, a further drive axle is now used, wherein the known from the prior art already known pivot arm is no longer mounted directly on the machine housing, but is mounted on the eccentric pin mounted in the machine housing eccentric shaft on the now z. B. the height of the bending tools can be set almost arbitrarily. This makes it possible to bring different bending levels with the workpiece in engagement, without causing a change in the bending plane occurs. At the same time, the loading height can be kept very low. The given in the inventive device three degrees of freedom (namely, eccentric shaft, swivel arm and rotation of the bending head) allow an extremely large freedom in the positioning of the bending head. Thus, the device according to the invention can be provided with support tables and it can be constructed more bending levels, at the same time realized a low loading height and the distance between the bending device and an associated workpiece magazine can be maximized.

In the invention, the bending plane can be rotated so that optimal conditions prevail and z. B. collisions between the workpiece and machine can be prevented. Large bent parts can be safely supported and bent and the workpieces can slide down on a table after completion.

In the device according to the invention, it is advantageous if the bending head carries two mutually offset by 180 ° with respect to the axis of rotation of the bending head on this bending tool units, advantageously each bending tool unit comprises at least one bending mold and a clamping jaws associated therewith, which the use of different bending tool units for bending without the requirement of replacing a bending tool unit used permits.

In an advantageous embodiment, the rotary arm and the bending head are each associated with a rotary drive, these rotary drives preferably within the pivot arm (or its cover) are added.

In a preferred embodiment of the device according to the invention, the pivot arm is designed in the form of an intermediate plate, with two eccentric, to each this is in each case pivotally engaged, wherein on the side facing the bending head side of the intermediate plate along this laterally movable carriage is mounted on which the bending head is rotatably mounted, each eccentric pin is supported by a pivot arm or an eccentric shaft, the or on Machine frame is mounted rotatably about an axis parallel to the feed direction of the workpieces, further on each of the bending head facing away from the intermediate plate one of the eccentric pin in an attached to the intermediate plate slot, in this slidably in the feed direction of the carriage engages while the other eccentric pin in a form-fitting manner an associated circular receptacle rotatably protrudes in the intermediate plate. In this solution, the engagement of an eccentric pin in the slot of the intermediate plate forms a rotary bearing with eccentric drive with a degree of freedom in the longitudinal direction of the carriage, which could well be realized in other ways than by engagement in a longitudinal hole in the intermediate plate (eg two guide rails on the intermediate plate, between which the corresponding eccentric pin slidably engages). The intermediate plate is thus connected to the one eccentric pin, pivotable about this, while the other eccentric pin in the slot of the intermediate plate, rotatable to this, is guided, whereby the intermediate plate can be adjusted both in height and in its orientation to the horizontal , On the intermediate plate then sits, along her movable, a carriage on which the bending head is rotatably mounted. Even with this solution can be set almost any height of the bending tool units or the bending plane can remain unchanged and thus turn a support table are used.

In the aforementioned embodiment of the device according to the invention preferably a rotary drive is associated with the bending head, which is mounted on the carriage, which contributes to a space-saving design.

Also preferably, each axis of rotation is assigned a separate drive in the device according to the invention, wherein advantageously all drives are program-controlled.

The inventive device allows automation with level changes even with large bending heads and a left-right change at low loading height and allows a very precise positioning of a left / right bending head.

Fig. 1

eine perspektivische Prinzipansicht einer erfindungsgemäßen Rohrbiegemaschine in der Stellung des Einführens eines Werkstückes in das geöffnete Biegewerkzeug;

Fig. 2

eine Ansicht von vorne auf die Rohrbiegemaschine gemäß Fig. 1 (wobei in der Darstellung relevante Elemente zum Positionieren des Biegekopfes dort, wo sie verdeckt sind, gestrichelt dargestellt werden);

Fig. 3-8

stellen Vorderansichten der Biegemaschine aus Fig. 1 dar, jedoch in unterschiedlichen Stellungen während des Arbeitszyklus der Maschine, dabei zeigen:

Fig. 3

eine Position, in welcher ein Werkstück vom Biegekopf der Maschine aus einem Magazin abgenommen wird;

Fig. 4

eine Stellung des Schwenkarmes der Vorrichtung nach einer Verschwenkung im Uhrzeigersinn zur koaxialen Ausrichtung von Werkstück und Spannzange miteinander;

Fig. 5

eine Stellung der Vorrichtung zum Biegen auf dem zweiten Biegeniveau (oberes Biegeniveau);

Fig. 6

eine Stellung, in welcher das Werkstück aus dem Biegewerkzeug ausgefädelt wird;

Fig. 7

einen Seitenwechsel, wobei der Biegekopf quer gestellt wird;

Fig. 8

die Stellung der Vorrichtung, nachdem das Biegewerkzeug auf der anderen Seite des Werkstücks wieder eingefädelt wurde;

Fig. 9

eine prinzipielle perspektivische Teildarstellung des vorderen Bereiches einer erfindungsgemäßen Vorrichtung gemäß einer alternativen Ausführungsform mit Zwischenplatte, und

Fig. 10

eine Vorderansicht der Ausführungsform der erfindungsgemäßen Vorrichtung gemäß Fig. 9.

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

Fig. 1

a perspective schematic view of a pipe bending machine according to the invention in the position of the insertion of a workpiece in the open bending tool;

Fig. 2

a front view of the pipe bending machine according to Fig. 1 (where in the illustration relevant elements for positioning the bending head where they are hidden, shown in phantom);

Fig. 3-8

display front views of the bending machine Fig. 1 but in different positions during the working cycle of the machine, showing:

Fig. 3

a position in which a workpiece is removed from a magazine by the bending head of the machine;

Fig. 4

a position of the pivot arm of the device after pivoting in a clockwise direction for coaxial alignment of the workpiece and the collet with each other;

Fig. 5

a position of the device for bending at the second bending level (upper bending level);

Fig. 6

a position in which the workpiece is threaded out of the bending tool;

Fig. 7

a side change, wherein the bending head is placed transversely;

Fig. 8

the position of the device after the bending tool has been re-threaded on the other side of the workpiece;

Fig. 9

a schematic partial perspective view of the front portion of a device according to the invention according to an alternative embodiment with intermediate plate, and

Fig. 10

a front view of the embodiment of the device according to the invention according to Fig. 9 ,

In the Fig. 1 in an oblique perspective from above shown bending machine 1 for elongated workpieces 2, such. B. pipes, wire o. Ä., Has a machine frame 3, at the top in its longitudinal direction parallel to each other two linear guides 23 are mounted on which a feed slide 4 in the longitudinal direction of the machine frame 3 is movable.

The feed carriage 4 carries at its front end a rotatable collet 5, which holds the workpiece 2 and by means of which it can also be rotated. At the front end of the machine frame 3 is how Fig. 1 shows, mounted a pivot arm 6 which is pivotally mounted on an eccentric pin 11 (see. Fig. 2 ) of an eccentric shaft 8 and can be pivoted relative to the latter about the central axis 12 of the eccentric pin 11 as a rotation axis.

The eccentric shaft 8 in turn is about a central axis of rotation 9, parallel to the feed direction x (see. Fig. 1 ) of the workpiece 2 is rotatable on the machine frame. 3 mounted, wherein the eccentric shaft 8 is associated with a not shown in the figures rotary drive.

At the end of the pivot arm 6 facing away from the eccentric pin 11, a bending head 7 is rotatably mounted about an axis of rotation 10, to which in turn a separate (not shown in the figures) rotary drive is assigned, which in turn is housed within the pivot arm 6. Similarly, a (not shown in the figures also) pivot drive is arranged on the pivot arm 6, by means of which the pivot arm 6 can be pivoted about the eccentric pin 11 relative to the eccentric shaft 8.

The pivotable about the rotary shaft 10 bending head 7 has two mutually opposite in the direction of rotation by 180 ° bending tool units 13, each of which comprises a bending mold 14 and a relative thereto or away from her adjustable clamping jaws 15.

The presentation of the Fig. 2 showing a front view of the bending machine 1 Fig. 1 shows that the bending mold 14 and the clamping jaws 15 of each bending tool unit 13 each comprise two superimposed bending molds, each of which determines its own bending level together with its associated portion of the clamping jaw 15.

The mechanisms and drives by means of which a workpiece 2 clamped by a jaw 15 at a certain bending level against the associated bending mold 14 and thus can be held to bending, are familiar to the expert and need not be further described or illustrated here.

The Fig. 3 to 8 now show basic front views of the bending machine from the Fig. 1 and 2 in different stages, as they can be approached during the working cycle of such a bending machine or need.

In Fig. 3 First, a pickup position is shown, in which a workpiece 2 is removed from the bending head 7 from a (not further shown) workpiece magazine. For this purpose, the eccentric shaft 8 is rotated so that the eccentric pin 11 is placed as far as possible in the direction of the workpiece 2, wherein at the same time the pivot arm 6 is pivoted in the direction of the workpiece 2 and the bending head 7 is rotated so that the workpiece 2 between the Clamping jaw 15 and the bending mold 14 threaded and can be clamped by these.

At the in Fig. 4 shown position is now the pivot arm 6 from the position Fig. 3 has been pivoted clockwise, wherein the bending head 7 is rotated in accordance with something clockwise relative to the pivot arm 6, so that the workpiece 2 and the Collet 5 of the feed carriage 4 are aligned exactly coaxial with each other. In this case, the workpiece 2 is transferred from the bending head 7 to the collet 5, to then make the desired bend.

In the Fig. 4 shown position also corresponds to the situation when bending in the first (lower) bending level, in Fig. 4 It can be seen clearly that here the bending axis A is exactly vertical and thus the bending plane B also runs exactly horizontally.

The bending plane B corresponds to the so-called "first" bending level defined by the lower rotational shape of the bending mold 14 of the longitudinal axis of the workpiece 2.

In Fig. 5 Now the position for bending with the second bending level is shown, which is determined by the upper rotational shape of the bending mold 14 and the associated upper mold recess 15 of the clamping jaw. The eccentric shaft 8 was, compared to the position Fig. 4 Turned somewhat counterclockwise, the pivot arm 6 is slightly rotated in a clockwise direction and the bending head 7 in the counterclockwise direction.

The presentation of the Fig. 6 now shows a position in which the workpiece 2 is threaded out of the bending tool. For this purpose, by a corresponding movement of the three pivot axes 9, 10 and 12 of the bending head 7 obliquely downward from the workpiece 2.

In Fig. 7 a side change is shown in which the bending head 7 is placed transversely (the bending axis A is horizontal), the eccentric pin 11 is lowered to the maximum and then the pivot arm 6 is rotated clockwise.

Finally, in Fig. 8 a position of the bending machine 1, which results after the bending tool 13 has been threaded again on the other side of the workpiece 2.

In the FIGS. 9 and 10 is shown another embodiment of a device according to the invention, wherein Fig. 9 shows in a perspective schematic representation of the front end of the machine frame 3 of a bending machine to which a bending head 7 is attached via an intermediate pivot arm in the form of an intermediate plate 16, and Fig. 10 shows a view of the device Fig. 9 from the front.

Like from the FIGS. 9 and 10 can be removed, at the front end of the machine frame 3 a bending machine, a pivot arm in the form of an intermediate plate 16 is attached to the machine frame 3 side facing away from a slide 19 in the longitudinal direction of the intermediate plate 16 is arranged.

The carriage 19 carries the bending head 7, which is rotatably arranged on the carriage 19 via a holder 25.

In the embodiment of the bending machine according to the FIGS. 9 and 10 are two eccentric pins 17, 18 are provided, each of which is attached to the end portion of a pivot arm 21 and 22, wherein the pivot arms 21, 22 rotatably mounted at their the eccentric pin 17, 18 facing end portions about axes of rotation 23 and 24 on the machine frame 3 of the bending machine ( see. Fig. 10 ) are.

In the illustrated embodiment, the two axes of rotation 23, 24 are arranged at the front end of the machine frame 3 at the same height, but laterally offset relative to each other so that the two pivot arms 21, 22 within the pivoting ranges, which they each cover in a work cycle of the bending machine, can not collide with each other.

The eccentric pin 17 of the one (in Fig. 10 in the front view right mounted) pivot arm 21 protrudes from the machine frame 3 facing the back of the intermediate plate 16 in an elongated hole 20 formed in this, in such a way that it both rotatable in the slot 20, as well as in the longitudinal direction, namely in the travel direction y of the carriage 19, is movably received. This arrangement thus forms a rotary bearing with eccentric drive and a degree of freedom in the direction of travel of the carriage y .

The provided on the other pivot arm 22 eccentric pin 18 is rotatably mounted in the intermediate plate 16 by 18 protrudes on the back in a dimension of the eccentric pin corresponding circular recess in which it is received rotatably.

Each of the two pivot arms 21, 22 is driven via a rotary drive (not shown in the figures), which is provided on or within the machine frame 3.

With the in the FIGS. 9 and 10 The arrangement shown, the intermediate plate 16 can be changed or moved both in height, as well as in their orientation to the horizontal, wherein the bending head 7 at the same time on the carriage 19 in turn along the intermediate plate 16 is movable.

The bending head 7 sits on the holder 25 (see, in particular Fig. 9 ), on which he is attached to the carriage 19 and within which also a (in the FIGS. 9 and 10 not shown) pivot drive for the bending head 7 sits.

In all embodiments shown in the figures, the rotary actuators for the bending head 7, the pivot arm 5 and the eccentric shaft 8 and (in the example of FIGS. 9 and 10 ) for the pivot arms 21 and 22 and the drive for moving the carriage 19 along the intermediate plate 16 to a central program control (not shown in the figures) connected, which the respective required rotation and travel movements for controlling the bending head 7 according to a predetermined bending program time-dependent controls.

Also in the embodiment of the FIGS. 9 and 10 can be set for the bending tools almost any altitude or the bending plane B can remain unchanged at a duty cycle and thus also the use z. B. a support table for the workpiece possible.

Even if the in the FIGS. 9 and 10 illustrated embodiment of the storage of the intermediate plate 16 has proved to be particularly advantageous, but may, for. B. the realized there by the protruding into the slot 20 eccentric pin 17 arrangement easily but also be replaced by another rotary bearing with eccentric and one degree of freedom in the travel direction y of the carriage 19, such as attached to the back of the intermediate plate 16 slide guide, which allows a pivot bearing for the eccentric pin 17, which can be moved simultaneously along the slotted guide in the direction of displacement of the carriage 19.

In certain embodiments, it is also possible instead of the pivot arms 21, 22 to provide eccentric shafts on which the eccentric pins 17, 18 are formed, in which case, however, the distance between the axes of rotation 23, 24 of such eccentric shafts must be correspondingly large, so that the two Eccentric waves can be twisted side by side unhindered.

In the pipe bending machine according to the invention, a mechanical, positive engagement takes place from the machine frame 3 on the front plate, which has the advantage that the elasticity of the guides is intercepted during bending with a large load by this positive locking, whereby the repeatability and fatigue strength of the bending machine can be improved.

Claims (9)

1. Device for bending bar-like workpieces (2), such as wire, tubes, rods or the like, having a machine frame (3), a workpiece feed (4) and a bending head (7) mounted on a pivot arm (6; 16) which is movable relative to said pivot arm, wherein the pivot arm (6; 16) is controllably pivotable relative to the machine frame (3) and the bending head (7) is controllably pivotable relative to the pivot arm (6; 16) in each case about at least one rotary axis (10, 12, 23, 24) running parallel to the direction (x) of the workpiece feed, characterised in that the rotary axis (12) of the swivel arm (6) is designed as an eccentric pin (11) of an eccentric shaft (8) or as a pin on a rotatable swivel arm, which in turn is rotatably mounted on the machine frame (3) about a central axis (9) running parallel to the feed direction (x) of the workpieces (2).
2. Device according to claim 1, characterised in that the bending head (7) bears two bending tool units (13) mounted thereon which are offset to one another by 180° with respect to the rotary axis (10) of said bending head (7).
3. Device according to claim 2, characterised in that each bending tool unit (13) comprises at least one bending die (14) and one clamping jaw (15) assigned thereto.
4. Device according to one of claims 1 to 3, characterised in that a rotary drive is assigned to each of the pivot arm (6) and the bending head (7).
5. Device according to claim 4, characterised in that the rotary drives of pivot arm (6) and bending head (7) are accommodated within said pivot arm (6).
6. Device according to one of claims 1 to 3, characterised in that the swivel arm is designed in the form of an intermediate plate (16), which is in engagement with two eccentric pins (17, 18), each pivotable thereabout, wherein a carriage (19) is attached on the side of said intermediate plate (16) directed towards the bending head (7) and is laterally traversable along said intermediate plate, the bending head being rotatably mounted on said carriage, each eccentric pin (17, 18) being supported by a swivel arm (21, 22) or an eccentric shaft, which is rotatably mounted on the machine frame (3) about an axis (23, 24) parallel to the feed direction (x) of the workpieces (2); in addition, on the side of the intermediate plate (16) directed in each case away from the bending head (7), one of the eccentric pins (17) engages in an elongated hole (20) located in the intermediate plate (16) and is movable in said elongated hole in the direction of travel (y) of the carriage (19), while the other eccentric pin (18) extends rotatably in a positive-locking manner into an assigned circular retainer in said intermediate plate (16).
7. Device according to claim 6, characterised in that a rotary drive which is mounted on the carriage (19) is assigned to the bending head (7).
8. Device according to one of claims 1 to 7, characterised in that a dedicated drive is assigned to each rotary axis (9, 10, 12, 23, 24).
9. Device according to claim 8, characterised in that all the drives are program-controlled.

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