EP2928680B1 - Press brake - Google Patents

Description

The invention relates to a press brake according to the preamble of claim 1.

Such a press brake is from the document US 3 327 515 A known.

Such press brakes usually have a vertical working plane, and is located in a conventional embodiment of the adjustable pressing beam above the fixed press table. The press table can be performed like a bar beam as well as the sake of simplicity, however, a fixed press beam is referred to as a press table in this application. In a press brake according to the invention, a bending plane deviating from the vertical direction may also be provided and, in the case of a vertical working plane, the adjustable pressing beam may also be arranged below the fixed press table.

In such press brakes, it is necessary that before and behind the bending plane sufficient space for the supply or the handling of machined or already machined workpieces is provided. For this reason, generic press brakes usually have in the direction of the bending edge spaced stand, which cause the required distance between the fixed press table and the adjustably mounted pressing beam and where often the adjustable pressing bar is performed.

As with larger bending edge lengths and / or larger workpiece thicknesses considerable forming forces must be applied to the workpiece, the fixed machine frame must have a high strength and rigidity, including the stand itself are made very stable and they must also be connected to each other stable. Very often there is a construction in which two so-called C-stands are connected to each other by means of the press table and an upper connecting bracket. At the C-stands usually a guide for the upper pressing beam is arranged and supports a drive means for the pressing beam on the fixed machine frame in the region of the stand or on the upper connection carrier. The drive means is formed, for example, as a hydraulic cylinder assembly and the cylinder housing is connected to the fixed connection carrier or the fixed uprights and acts the adjustable piston with a piston rod on the adjustable pressing beam. The cylinder housing of the hydraulic cylinder is supported on the underside of the connection carrier or is attached to the front side. By the former arrangement, results in a very high machine height, without thereby increasing the usable working height, while resulting in the second arrangement, a torsional moment on the connection carrier, which causes adverse deformations of the machine frame or machine frame.

The object of the invention is to provide a press brake, which simultaneously meets high demands on the bending accuracy with a simple construction of the machine frame and further has a high ease of assembly.

The object of the invention is achieved by a generic press brake with the characterizing features of claim 1.

Characterized in that at least one longitudinal portion of the connecting carrier or in at least one longitudinal section a predominant portion of the carrier cross section forming portion of the connecting carrier is formed by the drive means and this is releasably connected to a carrier base body of the connection carrier, the connection carrier can be positioned closer to the bending plane and exist in the arrangement of the drive means fewer restrictions than in a continuous connection carrier. Surprisingly, this embodiment of a connection carrier has no adverse effects on the rigidity of the machine frame. Since the drive means are usually arranged in the vicinity of the stand, a high deformation stiffness of the connection carrier is not of primary importance. The required installation space for the drive means and the connection carrier in this case are not mutually obstructive, but may overlap and the positioning of the connection carrier can be carried out in a stress-relieving manner, whereby a material saving can also be achieved due to smaller, required profile cross-sections. Due to the detachable connection of the drive means with the rest of the connection carrier, a modularity of the machine frame is achieved and can thereby the portability and ease of installation of such a press brake can be increased. The deformations of the machine frame occurring at high forming forces are partially lower or more easily calculated in advance by the embodiment according to the invention, whereby corrections of the forming process are more easily possible.

An advantageous embodiment of the press brake is that the longitudinal section or partial section formed by the drive means is arranged on an end section of the connection carrier and has a coupling surface which contacts one of the posts. The large driving forces of the drive means are thereby introduced directly into the stator and result in only low loads for the carrier body.

If the drive means forming a subsection of the connecting carrier is arranged on the side of the connecting carrier facing the pressing beam and the carrier base body has an upper belt bridging the drive means on the side facing away from the pressing beam, the tensile stresses arising upwards during bending of the connecting carrier can be absorbed by the upper belt. Since the drive means on the underside transmits the compressive stresses which occur upward upon deflection of the connecting carrier, only slight stresses of the connecting means used for the detachable connection result. For example, fastening screws in the region of the pressure side, ie on the side facing the pressing beam, can be made smaller. Furthermore, in the case of a continuous carrier main body connecting the two uprights, the drive means can be disassembled without the rest of the carrier main body having to be specially supported and secured against falling down.

A flexible embodiment of the press brake in which the adverse effects of deformation of the machine frame are reduced at high forming forces, is that the stands are in the form of C-stands, wherein the connection carrier at the bending plane facing upper ends of the C-frame. Stand is attached and each formed between the attachment point for the connection carrier on the C-stand and a central part of the C-stand, a deformation section with a locally reduced stator stiffness. The occurring at high forming forces bending of the C-stator and associated misalignment of the connecting carrier with the drive means can be reduced, since the connection carrier indeed initiates the forming forces in the C-stator, by the deformation portion with respect to the deformations partially from the main part of the C. Stand is decoupled and the skewing is reduced thereby.

A structurally simple way to form a deformation section through which the bending of the C-stator as little as possible to the connection carrier to a C-stator is that the arranged between the attachment point of the connection carrier at the upper end of the C-stand and the middle part deformation portion of the has the upper edge of the C-stand outgoing approximately parallel to the bending plane recess, in particular a parallel to the bending plane slot.

A good decoupling of the deformations of the attachment point of the main part of the C-stand is achieved when in the region of the recess, the cross section of the C-stator relative to adjacent cross-sections is reduced by at least one third.

If the recess for producing the deformation section is designed in the form of a slot, it can further be provided that the slot can be actively widened by an actuator acting on both sides of the slot. As a result, the plane of the press beam can be adjusted in a direction parallel to the bending plane.

The attachment point with the adjoining connection carrier can be aligned approximately parallel to the bending plane under the action of the forming forces, if the attachment point for the connection carrier on the C-stand has a greater distance from the press table than the reduced cross-section of the deformation region on the C-stand.

If the guide for the pressing beam with the bending plane has aligned guide rails, they need to absorb only small tilting moments, whereby they are exposed to less wear and may also be smaller in size. The guide rails can be mounted on the machine frame, whereby they interact with matching guide elements or guide shoes on the pressing beam, but it is also a reverse arrangement of the guide rails on the pressing beam and the guide elements on the machine frame possible.

An alternative or additional embodiment may consist in that the guide for the pressing beam on the connection carrier, in particular on the drive means, arranged guide rails comprises. These guide rails may be provided in addition to mounted on the stand guide rails. By the storage of the press beam at several Points are reduced to the bending plane right-angled deformations of the press beam, which promotes the Umformgenauigkeit.

A simple and modular construction of the connection carrier results when it comprises two drive means detachably connected to the uprights and a central section detachably arranged between them. The drive means form a supporting part of the connection carrier and is only slightly loaded by the direct connection of the drive means to the stator of the carrier body.

A structurally simple and yet rigid design of the connection carrier is given if its middle section comprises two spaced apart, parallel to the bending plane plate elements. The height of the plate elements is advantageously at least five times the thickness thereof, whereby a high flexural rigidity of the carrier base body is given with little use of material. Since the connection carrier can be placed by the inventive arrangement of the drive means in the bending plane, the torsional load is low even at high forming forces, which is why a simply constructed carrier body is sufficient.

The above-described embodiment of the connection carrier with two plate elements allows the pressing bar is at least partially positioned between the plate elements of the connecting carrier in its upper end position and thus can be performed with a greater height and thus bending stiffness without the overall height of the press brake must be increased.

A simple assembly or assembly of the drive means without separate measures for supporting the carrier base body can take place when parallel to the connection support of this two-stand connecting subcarrier is arranged and longitudinal sections and / or sections and / or a support base of the connection carrier by means of fasteners on the subcarrier fastened are.

To avoid tension between the drive means and the pressing beam, it is advantageous if between these a fixedly connected to a drivable and adjustable drive member of the drive means and the pressing beam, articulated bending element is arranged, which causes a pivotability of the press beam relative to the drive means about a right angle to the bending plane pivot axis. Bending moments resulting from a deflection of the press beam on the drive member, for example in the form of a piston rod, are thereby reduced, whereby the drive means, for example in the form of a hydraulic cylinder, is subjected to lower loads. The bending joint is compared to a pivot bearing backlash and low maintenance and for the small occurring tilt angle advantage.

In this case, the bending element can be arranged at the end of the drive member and have at right angles to the bending plane extending notches, in which preferably arranged on the pressing beam holding elements, in particular bracket engage. Thus, solely by the direction of the notches in a structurally simple manner, the direction of the relative mobility can be adjusted appropriately. The remaining residual cross section on the bending element is dimensioned such that sufficient operation against break is given during operation of the press brake.

If the drive means comprises at least two drive elements which are arranged parallel to one another and in particular to the bending plane and act on the pressing beam, a load with lower voltage peaks distributed over several points is produced both on the pressing beam and on the connection carrier. Furthermore, advantageous hydraulic circuits with rapid traverse function (rapid movement of the pressing beam at low force) and pressing function (slow movement of the pressing beam at high force) can be provided, for example, with a plurality of parallel hydraulic cylinders.

A prediction of the deformations of the connecting carrier occurring during a forming process is facilitated if the latter is formed, at least in sections, symmetrically with respect to a longitudinal center plane of the connecting carrier that is parallel to the bending plane.

In particular, when the longitudinal center plane of the connection carrier lies in the bending plane, the deformations to be expected are mainly bending deformations, since in this case the torsional moments are small.

In this context, it is furthermore of great advantage if the adjustment direction of the at least one drive means lies in the longitudinal center plane of the connection carrier, since tilting moments and torsional moments on the connection carrier are also minimized by this measure.

A precise guidance of the press beam, which is largely independent of the deformations of the stator required for Umformkraftübertragung, is made possible when the machine frame comprises at least two load carrier supporting the connection carrier and two of these different, the guide for the pressing beam having guide post.

When the pressing beam has on its opposite end faces with guide rails on the machine frame cooperating guide shoes which are fastened by means of a hinge element on the pressing beam, no harmful moments are introduced into the guides at a deflection of the press beam and consequent skewed at its ends.

In such an embodiment, in addition, the hinge elements can be arranged at the level of the neutral fiber of the press beam, whereby no constraining forces are transmitted in the longitudinal direction of the press beam on the lateral stand at a deflection of the press beam.

For a better understanding of the invention, this will be explained in more detail with reference to the following figures.

Fig. 1

eine perspektivische Ansicht einer möglichen Ausführungsform einer erfindungsgemäßen Abkantpresse;

Fig. 2

den Bereich des Verbindungsträgers einer weiteren Ausführungsform einer Abkantpresse;

Fig. 3

den Bereich eines Verbindungsträgers einer weiteren, möglichen Ausführungsform einer Abkantpresse;

Fig. 4

die Draufsicht auf einen Verbindungsträger einer weiteren, möglichen Ausführungsform einer Abkantpresse;

Fig. 5

einen Schnitt durch eine Abkantpresse gemäß Fig. 1;

Fig. 6

eine Seitenansicht einer Ausführungsform einer Abkantpresse;

Fig. 7

eine Teilansicht einer Abkantpresse mit möglichen Ausführungsformen von Führungen und einer möglichen Anbindung eines Antriebsmittels am Pressbalken;

Fig. 8

eine alternative Ausführungsform einer Anbindung des Antriebsmittels am Pressbalken;

Fig. 9

eine perspektivische Ansicht einer weiteren, möglichen Ausführungsform einer Abkantpresse;

Fig. 10

einen Schnitt durch eine mögliche Ausführungsform des Verbindungsträgers 8;

Fig. 11

einen Schnitt durch eine weitere mögliche Ausführungsform des Verbindungsträgers 8;

Fig. 12

eine Ansicht einer möglichen Ausführungsform der Führung des Pressbalkens am Maschinenrahmen.

Each shows in a highly schematically simplified representation:

Fig. 1

a perspective view of a possible embodiment of a press brake according to the invention;

Fig. 2

the region of the connection carrier of a further embodiment of a press brake;

Fig. 3

the region of a connection carrier of a further possible embodiment of a press brake;

Fig. 4

the top view of a connection carrier of another possible embodiment of a press brake;

Fig. 5

a section through a press brake according to Fig. 1 ;

Fig. 6

a side view of an embodiment of a press brake;

Fig. 7

a partial view of a press brake with possible embodiments of guides and a possible connection of a drive means on the pressing beam;

Fig. 8

an alternative embodiment of a connection of the drive means on the pressing beam;

Fig. 9

a perspective view of another possible embodiment of a press brake;

Fig. 10

a section through a possible embodiment of the connecting carrier 8;

Fig. 11

a section through another possible embodiment of the connecting member 8;

Fig. 12

a view of a possible embodiment of the guide of the press bar on the machine frame.

Fig. 1 shows a perspective view of a possible embodiment of a press brake according to the invention 1. This comprises a machine frame 2, which can also be referred to as a machine frame, and are formed on this, the other components of the press brake or mounted or adjustable. The machine frame 2 comprises two mutually distanced stand 3, 4, which are designed in the illustrated embodiment as a so-called C-stand 5, 6. These are essentially each with a user-side Recessed vertically standing plates in C-shape, which are connected at their lower ends with a fixed press table 7 and are connected at their upper ends by means of a connecting carrier 8. The press table 7 cooperates in the operation of the press brake 1 with an adjustably mounted pressing bar 9 and is defined by press table 7 and 9 pressing beam a bending plane. At the press table 7 and the pressing bar 9 tool holders are formed, which can not be shown bending tools are attached to perform the desired forming operations on workpieces.

The adjustable pressing beam 9 is mounted on the machine frame 2 by means of a guide 10, wherein the guide 10, for example guide rails 11, may comprise on the uprights 3, 4, which cooperate with guide elements on the pressing beam 9. In addition, a guide 10 may also be provided on the fixed connection carrier 8.

The adjustment of the press beam 9 relative to the machine frame 2 by means of at least one drive means 12, which comprises two hydraulic cylinders 13 in the illustrated embodiment. Alternatively or additionally, electrically driven embodiments are possible in addition to hydraulically acting drive means, e.g. with electric motor drive. The drive means 12 acts on the stationary machine frame 2 and on the adjustable pressing beam 9 and generates the forces required during operation of the press brake 1 for the movement of the press beam 9. On the closer version and the operation of the drive means 12, since largely known from the prior art omitted at this point.

The drive means 12 forms a detachable module of the connection carrier 8 and thus also of the machine frame 2 and forms an essential supporting component in the construction of the machine frame 2. The mechanically supporting component of the drive means 12 may be formed for example in a hydraulic cylinder through the cylinder housing or by another housing the drive means 12.

According to the invention, the drive means 12 forms a longitudinal section 14 of the connection carrier 8 connecting the uprights 3, 4 and is connected to the rest of the main body of the connection support 8 in FIG Fig. 1 a central portion 15 of the connecting carrier 8 is formed, releasably connected. In Fig. 1 the two hydraulic cylinders 13 form the two ends of the connecting carrier 8 and are further releasably connected to the uprights 3, 4. The drive means 12 have for this purpose coupling surfaces that contact the stator 3, 4. The detachable connection can be made by a variety of connecting means, for example by screw, pin connections, wedge connections, etc.

In contrast to known from the prior art embodiments of press brakes, in the embodiment according to the invention, the drive means 12 is not supported on the connection carrier 8 or on one of the stands 3, 4, but is a force-transmitting component of the connection carrier 8. The drive means 12 thus passes not only forces in the connection carrier 8, but is an essential part of the machine frame 2 and contributes to its deformation behavior directly.

At the in Fig. 1 illustrated embodiment of a press brake whose structure could also be described so that the main body of the connecting carrier 8, which is formed essentially from the central portion 15 is connected by means of the drive means 12 with the uprights 3, 4.

In Fig. 1 is a further possible embodiment of the press brake 1 according to the invention, in which the connection carrier 8 is fixed to the bending plane, upper ends of the C-stands 5, 6 and wherein between the attachment points 16 of the connection carrier 8 on the C-stand 5, 6 and a respective central part 17 of the C-stand 5, 6, a deformation section 18 is formed with a locally reduced stator stiffness. The connecting carrier 8 connecting the two C-stands 5, 6 to the fastening points 16 thus has a slight mobility with respect to the remainder of the C-stands 5, 6. As a result, the connecting carrier 8 can be moved even with a slight bending of the C-stands 5, 6 remain a vertical direction, whereby an undesirable relative displacement of the bending tools to each other can be largely prevented.

In the embodiment according to Fig. 1 the deformation portion 18 is formed by starting from the upper edge of a C-stand 5, 6, a recess 19 extending approximately parallel to the bending plane, in particular in the form of a slot 20, and thereby causes the above-described slight deformability of the attachment point 16 becomes. As in Fig. 1 is further shown, the central portion 15 of the connecting carrier 8 comprise two plate elements 21 parallel to the bending plane. Due to this distance between the two plate elements 21, it is further possible for the pressing beam 9 to have a higher cross section in its middle region and to be positioned at least partially between the plate elements 21 of the connecting carrier 8 when the pressing beam 9 is raised. As a result, the rigidity of the press beam 9 can be further increased without the overall height of the press brake 1 increasing.

In the FIGS. 2 and 3 Two alternative embodiments of connecting beams 8 are shown.

When connecting carrier 8 according to Fig. 2 form, similar to the execution according to Fig. 1 , The drive means 12 each have a longitudinal portion 14 of the connecting carrier 8. The drive means 12 are arranged in the illustrated embodiment at the ends of the connecting carrier 8 and contact with coupling surfaces 22, the two mutually distanced stator 3, 4, for example in the form of C-stands 5, 6th The connection carrier 8 further comprises the middle section 15 extending between the drive elements 12.

As Fig. 2 further indicated by dashed lines, drive means 12 may also be provided in the interior, for example in the central region of the connecting carrier 8 and thereby form further longitudinal sections 14 of the connecting carrier 8.

The drive means 12 are detachably connected to the rest of the connection carrier 8, in this case the middle section 15, wherein this connection is effected by means of connection means 23 symbolically indicated. The connection carrier 8 is also detachably connected with connecting means 23 to the uprights 3, 4. As connecting means 23 while screws, bolts, pins, wedges, etc. can be used, which allow a stable and backlash-free connection of the drive means 12 with the other parts of the connecting member 8 and the uprights 3, 4. In Fig. 2 The bending plane runs parallel to the drawing plane.

Since the pressing beam 9 is bent upwards during forming of a workpiece, in particular with high forming forces, an additional arrangement of a drive means 12 in the middle region of the connecting carrier 12, which is on the central region of the press beam. 9 acts to reduce or prevent the deflections of the press beam 9 and related geometry errors on the formed workpiece.

In Fig. 2 is by double arrows an adjustment 24 of the drive means 12 by means of driven, movable drive members moving, not shown, press bar 9 shown.

Fig. 3 shows an alternative embodiment of a connecting member 8, in which in a longitudinal portion 25 of the connecting member 8, a drive means 12 forms a portion 26 of the connecting member 8 and this portion 26 forms the majority of the carrier cross section 27 and this portion 26 releasably connected to the rest of the connecting member 8 is. Examples of such composed of the drive means 12 and a remainder of the connecting carrier 8 carrier cross sections 27 are in further 10 and 11 shown.

The formed by the drive means 12 portion 26 of the connecting member 8 is bound by the releasable connection in the power flow between the uprights 3, 4 and thereby a supporting part of the connection support 8. The rest of the connecting support 8, which is not formed by a drive means 12 may Also be referred to as a carrier body 28, as well as in the Fig. 1 . 2 and 3 in Fig. 1 shown central portion 15 forms a carrier body 28. The longitudinal section 14 in the Fig. 1 and 2 or the section 26 in Fig. 3 thus replaces a part of the carrier base body 28 and complement this to form an overall, modularly constructed connection carrier 8.

In Fig. 3 are the drive means 12, which form portions 26 of the connecting carrier 8, arranged at the two end portions of the connecting support 8 and contact as well as in Fig. 2 with coupling surfaces 22, the stand 3, 4 and the C-stand 5, 6. It is also provided between the drive means 12 and the uprights 3, 4, a releasable connection by means of connecting means 23.

In Fig. 3 the partial section 26 formed by the drive means 12 is bridged in the longitudinal section 25 of the support base body 28, wherein this is designed in the illustrated embodiment as a top flange 29 with a rectangular cross-section. The carrier body 28 may For example, be designed as a 1-carrier and have in the longitudinal sections 25 for insertion of the drive means 12 corresponding notches. In order to be able to produce a stable, releasable connection of the carrier base body 28 with the drive means 12, end plates 30 can be used on the carrier base body 28 in the region of the notch.

In the execution according to Fig. 3 the drive means 12 forming a partial section 26 of the connecting carrier 8 is arranged on the side of the connecting carrier 8 facing the pressing bar 9 and the upper belt 29 bridging the drive means 12 is arranged on the side of the connecting carrier 8 facing away from the pressing bar 9.

The upper flange 29 is advantageously tension-resistant connected to the uprights 3, 4 and is further arranged at a deflection of the connecting carrier 8 upwards on the tension side. The drive means 12 is arranged at a deflection of the connecting carrier 8 upwards on the pressure side and is thus effectively clamped between the carrier base body 28 and the uprights 3, 4 and thereby results in lower stresses on the pressure side for the connecting elements 23. The connecting elements 23 are on the connection points between the carrier body 28 and drive means 12 and between the drive means 12 and uprights 3, 4 advantageously arranged at least in pairs and in the direction of deflection of the connecting carrier 8, which also bending moments can be transmitted to this detachable connection and the components of the machine frame 2 characterized stiffen each other.

Fig. 4 shows a view according to arrow IV in Fig. 1 , in which the region of the fastening point 16 of the connecting support 8 is shown with the stand 3 of the press brake 1 in a further possible embodiment, which emphasizes the modularity of the press brake 1 according to the invention.

The connecting carrier 8 has at its end portion successively formed by two drive means 12 longitudinal sections 14, wherein the in Fig. 4 left drive means 12 and the in Fig. 4 right drive means 12 are releasably connected to the carrier base body 28 using connection means 23 and the two drive means 12 are also releasably connected to each other by means of connecting elements 23. The drive means 12, for example in the form of hydraulic cylinders, are preferably in their action lines The longitudinal center plane 31 of the connecting member 8 and is advantageously also the support base 28 and the entire connection support 28 at least partially symmetrical with respect to the longitudinal center plane 31, which further preferably coincides with the plane defined between press table 7 and 9 press beam bending plane 32.

Due to the fact that the adjustment direction 24 or the plane of action of the drive means 12 coincides both with the longitudinal center plane 31 of the connection carrier 8 and with the bending plane 32, no or only very small torsional moments are introduced into the connection carrier 8 by the forming forces. As already in Fig. 1 illustrated, the carrier body 28 may comprise two mutually parallel, spaced plate members 21. The intermediate space between such two plate elements 21 can simultaneously form a movement space for the pressing beam 9.

Fig. 4 shows, as in the previous one Fig. 1 to 3 , a press brake 1 with a plate-shaped stator 3 in the form of a C-stand 5, but the invention also relates to all possible other stator forms, such as O-stand, pillar stand, hollow profile stand, etc.

Fig. 5 shows a sectional view of a press brake 1 according to the embodiment Fig. 1 , wherein the cutting plane is vertical and perpendicular to the bending plane 32.

The sectional view shows that the pressing beam 9 is positioned with its central region in the raised position in the space between the plate elements 21 of the connecting carrier 8 and the pressing bar 9 can be performed by this gap in its central region with a substantially greater height than in its end regions, in which the drive means 12 attack. Since the bending moments have their maximum mostly in the middle region on the pressing beam 9, this enlarged cross section of the pressing beam 9 is advantageous for its rigidity.

As based on the Fig. 1 and 5 is easily recognizable, the connection carrier 8 is held on the releasable connection between the drive means 12 and stator 3 in its position. Now, if the replacement of a drive means 12 is required on the connection carrier 8, this is to be secured in a suitable manner against an unwanted drop, for example in the one Weight is borne by a temporary support. It is advantageous, however, if an auxiliary carrier 33 is provided parallel to the connection carrier 8, to which during the replacement of individual components of the connection carrier 8, the remaining, remaining components are connected by means of suitable connecting means with the auxiliary carrier 33 and carried by this. For example, the carrier body 28, in Fig. 5 in the form of two plate elements 21 are fixed by means of a connecting means 34, for example a bolt 35 in its position with respect to the subcarrier 33 and then the drive means 12 can be dismantled.

Fig. 6 shows a side view of the press brake 1 according to Fig. 1 from the left. One recognizes the simply constructed machine frame 2, which consists essentially of the two mutually spaced stands 3, 4 in the form of the C-stand 5, 6, which are connected to each other in the region of the bending plane 32 via the press table 7 and the connection carrier 8. Fig. 6 also shows the optional recess 19 in the form of a slot 20, whereby the C-stator 5 in the region of the slot 20 has a cross-section 36 which is substantially smaller than the adjacent cross-sections 37 of the C-stator 5, whereby a deformation portion 18 is formed is that causes a locally reduced stator stiffness for the attachment point 16 of the connection carrier 8 on the C-stand 5 and 5 only small torsional moments are transmitted between the connection carrier 8 and C-stator. In a possible bending of the C-stand 5, the connection support 8 does not necessarily have to tilt back to the same extent and the connection support 8 and the press beam 9 connected thereto can remain substantially parallel to the bending plane 32.

In Fig. 7 is a partial view of the connection of the press beam 9 shown on the machine frame 2. The connection carrier 8 is as in the embodiment according to Fig. 1 from the carrier body 28 and the one longitudinal portion 14 of the connecting member 8 forming drive means 12 together and these are releasably connected to each other by means of connecting means 23. The drive means 12 at the end portion of the connecting member 8 contacted with a coupling surface 22, the stator 3 and C-stator 5 and is also releasably connected thereto via connecting means 23.

The drive means 12 has on the pressing beam 9 acting on adjustable and driven drive members 38 which are formed in the case of a drive means 12 in the form of a hydraulic cylinder 13 by piston rods 39. In Fig. 7 the drive means 12 comprises three mutually parallel and lying in the bending plane 32 piston assemblies and thus engage the illustrated left end portion of the press beam 9 three piston rods 39 at. The hydraulic cylinder 13 may also have only a single piston assembly, the generation of the required drive forces by means of several piston arrangements allows drive means 12 with low expansion perpendicular to the bending plane 32, whereby a required for the forming of large workpieces clearance is minimized.

An advantageous, optional embodiment of this connection of the press beam 9 on the drive means 12 may be that with the drive means 12, here with the drive members 38 and the pressing bar 9, firmly connected, articulated bending elements 40 are provided, whereby the pressing bar 9 a slight pivotability obtained relative to the drive means 12 about a right angle to the bending plane 32 pivot axis.

In Fig. 7 a bending element 40 is formed such that two lateral notches 41 are arranged at the lower end of the piston rods 39, wherein the notches 41 extend at right angles to the bending plane 32. Due to this weakening of the cross section of the bending element 40 at the piston rod end, the bending element 40 has the function of a joint and no high and thus harmful bending moments are transmitted to the drive members 38 and the piston rods 39 at a possible deflection of the press beam 9.

At the voltage applied to the press beam 9 ends of the flexure 40 can, as in Fig. 7 represented, by means of holding elements 42, for example in the form of brackets 43, a detachable connection of the drive means 12 may be made with the pressing bar 9.

In Fig. 7 the brackets 43 are arranged to connect the drive members 38 to the pressing beam 9 at right angles to the bending plane 32, whereby during assembly of the press beam 9 this perpendicular to the bending plane 32 on the ends of the drive members 38, here the piston rods 39, can be postponed. The assembly and disassembly takes place at the in Fig. 1 and 5 illustrated embodiment in the lowered position of the press beam 9, in which he is no longer between the plate elements 21 of the connecting member 8 in the central region.

In Fig. 7 Furthermore, an additional possible embodiment variant for the guide 10 of the press beam 9 on the machine frame 2 is shown. The guide 10 includes guide rails 11 on the stand 3 and additional guide rails 44 which are attached to the drive means 12. Advantageously, the guide rails 11 and 44 lie in the bending plane 32, whereby the pressing bar 9 brings on the guide 10 no or only slight tilting moments. In the illustrated embodiment, the guide rails 44 are arranged between the two the carrier base body 28 forming plate members 21 and the pressing bar 9 is thereby guided at its enlarged central region.

In order to achieve an exact guidance of the press beam 9, this guide shoes 45, which comprise the guide rails 11, 44 approximately free of play. In this embodiment of the guide 10, the pressing beam 9 is guided in four points, these four points being guided along straight lines formed by the guide rails 10, 44. Since the pressing beam 9 in the illustrated embodiment has a large height, and 9 may result in a forming process due to the deflection of the press beam 9 different changes in length at the guide points, can further in a Fig. 7 Also shown in the longitudinal direction of the press bar 9 extending length compensation guide 46 may be provided for the guide shoe 45.

The guide 10 can thus comprise guide rails 11 on the uprights 3, 4 as well as additional guide rails 44 on the connection support 8, which can be arranged on the drive means 12 and / or on the carrier main body 28.

Fig. 8 shows in a partial view of another possible embodiment of the connection of the press beam 9 on the drive member 38 of the drive means 12, wherein here another embodiment of the flexure 40 is shown, with a slight angular mobility between the drive member 38 and the pressing bar 9 is achieved and thereby in a possible deflection of the press bar 9, no bending moments which might possibly damage the drive means 12 are introduced into the drive member 38. The flexure 40 is formed in this embodiment on the pressing bar 9 itself by at the top 47 of the Press beam 9 two mutually facing L-shaped recesses 48 are provided, between which there is a reduced residual cross-section, which causes increased deformability and thus bending mobility. As a holding element 42 between the drive member 38 and the pressing bar 9 can serve in this embodiment, a screw member.

Fig. 9 shows a view of a further possible embodiment of a press brake 1 according to the invention with an alternative embodiment of the machine frame 2. The C-stand 5, 6 formed stator 3 and 4, which carry the connection carrier 8 with the drive means 12 and the pressing bar 9, are in Essentially composed of two main parts. The connecting support 8 is supported by load stands 49, which can also be referred to as a power frame, since the power flow from the press table 7 to the connecting support 8 and subsequently via the drive means 12 to the press beam 9 is produced thereon. These substantially C-shaped load stands 49 are slightly bent at high forming forces due to the inevitable, elastic deformations, whereby the connection carrier 8 undergoes a slight change in position and angle. The guide 10 for the pressing beam 9, however, is arranged on a separate guide stand 50, via which no forming forces must be transmitted and therefore can hold the guide rails 11 of the guide 10 even with large forming forces in an exact largely unchanged position. In Fig. 9 the guide post 50 is made in two parts and lies in the same plane as the load stand 49, wherein a part is located within the load stand 49 and a part outside the load stand 49 and the two parts are connected by parallel to the stator level plates arranged in Fig. Am left C-stand 5 for the purpose of representation of load stand 49 and guide stand 50 are not shown.

The inevitably occurring at large forming forces, different deformations of load stand 49 and guide post 50 would cause tension in the connection between the acting on the load stand 49 drive means 12 and guided on the guide post 50 pressing beam 9, however, can be avoided that between the attachment point 16th and the middle part 17 of the load stand 49, a deformation section 18 is provided, which eliminates or reduces the rigid connection of the connecting member 8 with the rest of the load stand 49 in such a way that even at a bend of the load stand 49 can be an angle matching of the connecting carrier 8 with the drive means 12 to the guide 10.

This also makes it possible to guide the pressing beam 9 not only on the guide stand 50, but also in addition to the connecting support 8, as already described with reference to FIG Fig. 7 is described. By such a deformation region 18, as he also according to the embodiment according to Fig. 1 has already been described, even at high forming forces and associated deformations of the machine frame 2 allows only very small internal tension between the drive means 12 and the pressing bar 9, whereby the drive means 12 and the guides 10 are charged much less.

In the 10 and 11 are shown in sectional views in the region of the drive means 12 possible embodiments of the connection carrier 8.

In Fig. 10 the carrier base body 28 is formed by an I-beam 51, which is so disengaged in the region of the drive means 12 that here only the upper flange 29 bridges the drive means 12. This version is essentially the same as in Fig. 3 illustrated embodiment of a connection carrier. 8

Fig. 11 shows a possible embodiment of the connecting carrier 8, in which the carrier base body 28 is designed as a U-profile, in which the drive means 12 is inserted at the open bottom. Due to the not shown, detachable connection of the drive means 12 with the carrier base body 28 and the stator 3, 4 this is despite a continuous support base body 28 is a supporting part of the connection carrier. 8

In modification of the execution according to Fig. 11 could further be the support body 28 designed as a T-profile with a downwardly projecting central web and in turn the pressing beam 9 two mutually parallel and distant plates comprise, which receive in the raised position of the press bar 9 between them the central web of the support body 29.

10 and 11 show that the drive means in the respective longitudinal portion 25 (see Fig. 3 ) forms the predominant portion of the support section 27.

In Fig. 6 are still features of additional embodiments of the press brake 1 shown, which may be provided in addition to or alternatively to the above-described embodiments.

The deformation region 18 can also be formed in such a way that the attachment point 16 of the connecting support 8 is arranged with the stator 3, or the C-stator 5 in a region of the stator 3 with a relatively small deformation stiffness. For this, the C-stand 5 may be e.g. be executed without recess 19 or slot 20, but at the height which extend horizontally to the rear of the lower end of the slot 20 shown, as indicated by a dashed line shown at this height upper edge.

Furthermore, in one embodiment of the C-stand 5 with a slot 20, an actuator 51 acting on both sides of the slot can be provided, with which the widening of the slot 20 can be actively influenced. This can consist in an active enlargement, a reduction or a limitation of the expansion. As a result, the orientation of the connecting carrier 8 can be actively influenced and in particular adapted to the bending plane 32.

Fig. 12 shows yet another possible embodiment of the guide 10 of the press beam 9 on the side uprights 3, 4. The cooperating with the guide rails 11 guide shoes 45 are fastened by means of hinge elements 53 on the end faces 52 of the press beam 9, whereby at a deflection of the press beam 9 no harmful Moments are introduced into the guide 10. Since the press beam 9 undergoes an extension at a deflection above its neutral fiber 54 and a shortening below the neutral fiber 54, it is advantageous if, as in FIG Fig. 12 represented the hinge elements 53 are arranged at the height of the neutral fiber 54, since in this case no additional acting in the beam longitudinal direction tensile or compressive forces are introduced into the stand 3.4 by a Pressbalkendurchbiegung. The joint elements may be designed as conventional joints with a pin-shaped joint axis or as a bending joint, similar to the previously described bending elements 40 for connecting the press beam 9 to the drive means 12th

The embodiments show possible embodiments of the press brake 1, wherein it should be noted at this point that the invention is not limited to the specifically illustrated embodiments thereof, but also various combinations of the individual embodiments are mutually possible and this possibility of variation due to the teaching of technical action representational invention in the skill of those skilled in this technical field. So are all conceivable embodiments, which are possible by combinations of details of the illustrated and described embodiment variant, includes the scope of protection.

Furthermore, it should be noted that in the differently described embodiments, the same parts are provided with the same reference numerals or identical component names, wherein the disclosures contained in the entire description can be mutatis mutandis to the same parts with the same reference numerals or the same component names. Also, the location information chosen in the description, such as top, bottom, side, etc. related to the immediately described and illustrated figure and are to be transferred to the new situation mutatis mutandis when a change in position. Furthermore, individual features or combinations of features from the different exemplary embodiments shown and described can also represent independent, inventive or inventive solutions.

All statements on ranges of values in the description of the present invention should be understood to include any and all sub-ranges thereof, e.g. the indication 1 to 10 should be understood to include all sub-ranges, starting from the lower limit 1 and the upper limit 10, i. all subregions begin with a lower limit of 1 or greater and end at an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1 or 5.5 to 10.

For the sake of order, it should finally be pointed out that, for a better understanding of the structure of the press brake 1, these or their components have been shown partly unevenly and / or enlarged and / or reduced in size.

The task underlying the independent inventive solutions can be taken from the description.

Above all, the individual in the Fig. 1 ; 2 ; 3 ; 4 ; 5 ; 6 ; 7 ; 8th ; 9 ; 10 ; 11 ; 12 shown embodiments form the subject of independent solutions according to the invention. The relevant objects and solutions according to the invention can be found in the detailed descriptions of these figures. <B> Reference Numbers </ b> 1 press brake 31 Longitudinal center plane 2 machine frame 32 bending plane 3 stand 33 subcarrier 4 stand 34 connecting means 5 C-frame 35 bolt 6 C-frame 36 cross-section 7 press table 37 cross-section 8th connection support 38 drive member 9 pressing bars 39 piston rod 10 guide 40 flexure 11 guide rail 41 notch 12 drive means 42 retaining element 13 hydraulic cylinders 43 bracket 14 longitudinal section 44 guide rail 15 midsection 45 guide shoe 16 fastening point 46 Longitudinal leveling guide 17 midsection 47 top 18 deforming section 48 recess 19 recess 49 Last stand 20 slot 50 guide posts 21 panel member 51 actuator 22 coupling surface 52 front 23 connecting means 53 joint element 24 adjustment 54 neutral fiber 25 longitudinal section 26 part Of 27 Carrier section 28 Support body 29 upper chord 30 Stirnflech

Claims (23)

1. A press brake (1) comprising a machine frame (2), a stationary press table (7) which is connected to the machine frame, a press beam (9) mounted on a guide (10) on the machine frame (2) in a linearly movable manner in the direction of the press table (7), and at least one drive means (12) which engages on the press beam (9) and on the machine frame (2), wherein the machine frame (2) comprises at least two stands (3, 4), in particular flat C-stands (5, 6) or O-stands which are arranged transversely to a bending plane (32) extending from the press table (7) to the press beam (9), and the machine frame comprises a connecting support (8) which connects two adjacent stands (3, 4), characterized in that at least one longitudinal portion (14) of the connecting support (8) is formed by the drive means (12) or in at least one longitudinal portion (25) a sub-portion (26) of the connecting support (8), forming the predominant portion of the support cross-section (27), is replaced by the drive means (12) and the latter is removably connected to a support main part (28) of the connecting support (8).
2. The press brake (1) according to claim 1, characterized in that the longitudinal portion (14), formed by the drive means (12), or sub-portion (26), is arranged on an end portion of the connecting support (8) and has a coupling surface (22), which contacts one of the stands (3, 4).
3. The press brake (1) according to claim 1 or 2, characterized in that the drive means (12) forming a sub-portion (26) of the connecting support (8) is arranged on the side of the connecting support (8) facing the press beam (9), and the support main part (28) has on the side facing away from the press beam (9) an upper belt (29) bridging the drive means (12).
4. The press brake (1) according to one of the preceding claims, characterized in that the stands (3,4) are embodied in the form of C-stands (5, 6), wherein the connecting support (8) is fastened to the upper ends of the C-stands (5, 6) pointing to the bending plane (32), and respectively between the fastening point (16) for the connecting support (8) on the C-stand (5, 6) and a central part (17) of the C-stand (5, 6) a deformation portion (18) with a locally reduced stand rigidity is formed.
5. The press brake (1) according to claim 4, characterized in that the deformation portion (18), arranged between the fastening point (16) at the upper end of the C-stand (5,6) and its central part (17), has an opening (19) originating from the upper edge of the C-stand (5,6), running approximately parallel to the bending plane (32), in particular a slot (20) parallel to the bending plane (32).
6. The press brake (1) according to claim 5, characterized in that in the region of the opening (19), the cross-section (36) of the C-stand (5, 6) is reduced by at least one third compared to cross-sections (37) adjacent thereto.
7. The press brake (1) according to claim 5 or 6, characterized in that at the opening (19) in the form of a slot (20) an actuator (51) is provided for the active influencing of the widening of the slot (20).
8. The press brake (1) according to one of claims 4 to 7, characterized in that the fastening point (16) for the connecting support (8) on the C-stand (5, 6) has a greater distance to the press table (7) than the reduced cross-section of the deformation region (18) on the C-stand (5, 6).
9. The press brake (1) according to one of the preceding claims, characterized in that the guide (10) for the press beam (9) has guide rails (11) aligned with the bending plane (32).
10. The press brake (1) according to one of the preceding claims, characterized in that the guide (10) for the press beam (9) comprises guide rails (44) arranged on the connecting support (8), in particular on the drive means (12).
11. The press brake (1) according to one of the preceding claims, characterized in that the connecting support (8) comprises two drive means (12) removably adjoining the stands (3, 4), and a central portion (15) removably arranged between these.
12. The press brake (1) according to one of the preceding claims, characterized in that the support main part (28) of the connecting support (8) comprises two plate elements (21), distanced from one another, parallel to the bending plane (32).
13. The press brake (1) according to claim 12, characterized in that the press beam (9) at its upper end position is positioned at least partially between the plate elements (21) of the connecting support (8).
14. The press brake (1) according to one of the preceding claims, characterized in that an auxiliary support (33), connecting two stands (3, 4), is arranged parallel to the connecting support (8), distanced therefrom, and the longitudinal portions (14) and/or sub-portions (26) and/or a support main part (28) of the connecting support (8) are able to be fastened to the auxiliary support (33) by means of connecting elements (34).
15. The press brake (1) according to one of the preceding claims, characterized in that between the drive means (12) and the press beam (9) a bending element (40), acting in a joint-like manner, securely connected to a drivable and adjustable drive member (38) of the drive means (12) and the press beam (9), is arranged, wherein said bending element brings about a pivotability of the press beam (9) relative to the drive means (12) about a pivot axis at right angles to the bending plane (32).
16. The press brake (1) according to claim 15, characterized in that the bending element (40) is arranged at the end of the drive member (38) and has indentations (41) running at right angles to the bending plane (32), into which holding elements (42), in particular holding angles (43), preferably arranged on the press beam (9), engage.
17. The press brake (1) according to one of the preceding claims, characterized in that the drive means (12) comprises at least two drive members (38) arranged parallel to one another, and in particular to the bending plane (32), and engaging on the press beam (9).
18. The press brake (1) according to one of the preceding claims, characterized in that the connecting support (8) is embodied at least partially symmetrically with respect to a longitudinal centre plane (31) of the connecting support (8) parallel to the bending plane (32).
19. The press brake (1) according to one of the preceding claims, characterized in that the longitudinal centre plane (31) of the connecting support (8) lies in the bending plane (32).
20. The press brake (1) according to one of the preceding claims, characterized in that the adjusting direction (24) of the at least one drive means (12) lies in the longitudinal centre plane (31) of the connecting support (8).
21. The press brake (1) according to one of the preceding claims, characterized in that the machine frame (2) comprises at least two load stands (49) carrying the connecting support (8) and two guide stands (50), different therefrom, having the guide (10) for the press beam (9).
22. The press brake (1) according to one of the preceding claims, characterized in that the press beam (9) has on its opposite face sides (52) guide shoes (45) cooperating with guide rails (11) on the machine frame (2), which guide shoes are fastened to the press beam (9) by means of a joint element (53).
23. The press brake (1) according to claim 22, characterized in that the joint elements (53) are arranged in the height of the neutral axis (54) of the press beam (9), in relation to a bending in adjusting direction (24) of the press beam (9).

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