Guillotine shear with sheet metal holding device

Abstract

Sheet metal shear (1) suitable for sheet metal processing for front and rear discharge of a cut sheet metal piece (45), comprising - a machine frame (2), - a table (5) with a lower knife (6) attached to it, and - a carriage (10) movable relative to the table (5) by means of a drive unit, with an upper blade (16) attached to the carriage (10) and a sheet metal holding device (18) attached to the carriage (10), having the following features: - the table (5) forms a table support surface (7) which is aligned with a cutting edge (8) of the lower knife (6); - the carriage (10) together with the upper knife (16) and the sheet metal holding device (18) can be moved between an OT position and an UT position by means of the drive unit, in particular perpendicular to the table support surface (7); - the sheet metal holding device (18) comprises at least one swivel arm (26) and a swivel platform (24) with a sheet metal support surface (25), which is in particular formed from several sheet metal support rails (36); - the at least one pivoting arm (26) is pivotably mounted on the slide (10) about a first pivoting axis (28) which runs in particular parallel to the cutting edge (8); - the pivoting platform (24) together with the sheet metal support surface (25) is pivotably mounted on at least one pivoting arm (26) about a second pivoting axis (29) which in particular runs parallel to the cutting edge (8), so that the sheet metal support surface (25) can be pivoted about both the first pivoting axis (28) and the second pivoting axis (29).

Description

[0001] The present invention relates to a guillotine shear for sheet metal processing, comprising a machine frame, a table with a lower blade attached thereto, an upper blade movable relative to the table by means of a drive unit and a sheet holding device, wherein the table forms a support surface which is aligned with a cutting edge of the lower blade.

[0002] Such guillotine shears have been known in the art and used for many years to cut metal sheets along a cutting edge. The sheet support device facilitates the positioning of the sheet to be processed (cut) relative to the cutting edge. While the sheet is being positioned, the table support surface of the table and a sheet support surface of the sheet support device are (essentially) in a common plane, with the table and the sheet support device being arranged on different sides of the lower blade. In this way, the sheet to be processed can be supported on either side of the lower blade during positioning, so that even if the sheet protrudes far beyond the lower blade, bending and / or tipping of the sheet can be prevented.

[0003] The sheet metal piece to be processed is typically inserted into the guillotine shear via the front of the machine (by a human operator or a robot). Depending on whether the cut workpiece is discharged to the front or the (opposite) rear of the guillotine shear, this is referred to as front- or rear-side discharge / removal of the workpieces, or front- or rear-side discharge / removal.

[0004] To facilitate or enable the removal or dispensing of the cut (sheet-shaped) workpieces (sheet metal pieces), the sheet support surface of the sheet support device is often designed to be tiltable. By tilting the sheet support surface "forward", i.e. towards the lower blade into a first sheet support position, the front-side workpiece removal can be facilitated or enabled. Similarly, tilting the sheet support surface "backward", i.e. in the opposite direction and thus away from the lower blade into a second sheet support position, can facilitate or enable the rear-side removal / dispensing of the cut workpiece. The option of removing the workpiece from both sides enables more flexible use of the guillotine shears and can promote efficiency.For example, a workpiece can be output from the front or back depending on its dimensions or material properties and thus sorted, which facilitates further processing.

[0005] DE 10 2009 051 190 B3 of the applicant shows a guillotine shear with a pivoting tilting table by means of which cut-off pieces of sheet metal can be discharged to the front.

[0006] As an example, the document FR 2579500 A1 describes a guillotine shear with a sheet metal holder that is height-adjustable and can be tilted both forwards and backwards.

[0007] The document EP 0 008 963 B1 also describes a guillotine shear with a swivel plateau that can be swivelled to two sides (cf. 44, Fig. 6A-6D) with a sheet metal support surface. The pivoting plateau (44) can be pivoted along two pivot axes (45, 46) relative to an arm (47) rigidly connected to a carriage.

[0008] Against this background, the present invention is based on the object of providing a guillotine shear of the type described above with a sheet metal holding device which is characterized by particular cost-effectiveness and reliability, both with regard to production and operation.

[0009] This problem is solved by the guillotine shears according to the invention specified in the independent patent claim. Advantageous embodiments are specified in the dependent claims.

[0010] The plate shear according to the invention for sheet metal processing is suitable for the front and rear output of a cut piece of sheet metal, comprising - a machine frame, - a table with a lower knife attached to it, and - a carriage movable relative to the table by means of a drive unit, with an upper knife attached to the carriage and a sheet holding device attached to the carriage, with the following features: - the table forms a table support surface which is aligned with a cutting edge of the lower blade; - the carriage, together with the upper knife and the sheet holding device, can be moved by means of the drive unit (in particular perpendicular to the table support surface) between a (raised) TDC position and a (lowered) BDC position; - the sheet holding device comprises at least one pivoting arm and a pivoting plateau with a sheet support surface (which is formed in particular from several sheet support rails); - the at least one pivot arm is mounted on the carriage so as to be pivotable about a first pivot axis (in particular running parallel to the cutting edge); - the pivoting plateau, together with the sheet support surface, is mounted on at least one pivot arm so as to be pivotable about a second pivot axis (running in particular parallel to the cutting edge), so that the sheet support surface can be pivoted both about the first pivot axis and about the second pivot axis.

[0011] According to the invention, the carriage, together with the upper blade and the sheet holding device, can be moved between a TDC position and a BDC position. Those skilled in the art will know that "TDC" stands for "top dead center" and "BDC" for "bottom dead center." To position a sheet metal panel to be machined, the carriage is moved to its TDC position, where the wedge-shaped gap between the upper and lower blades is at its maximum.

[0012] In order to ensure that the sheet support surface and the table support surface lie in a common plane in the TDC position of the slide, the swivel arm, the swivel plateau and thus the sheet support surface are moved into a (horizontal) starting position. This is preferably achieved by swiveling the swivel arm against an upper swivel arm stop and, at the same time, swiveling the swivel plateau against an upper swivel plateau stop. The interaction of these two upper stops with the swivel arm or the swivel plateau defines the (horizontal) starting position of the sheet support surface. However, the swivel arm and swivel plateau can also be positioned accordingly without (mechanical) stops in other ways, e.g. by means of position-controlled or angle-controlled actuators.

[0013] The guillotine shear according to the invention enables the pivoting platform and thus the sheet metal support surface to be pivoted from this horizontal starting position into two different pivoting platform positions, which enable or facilitate the removal or dispensing of the cut-off workpiece from both sides. If the sheet metal support surface is pivoted (starting from the starting position) into the first of the two pivoting platform positions, this enables or facilitates the front-side removal of the cut-off workpiece (removal "to the front"). If, on the other hand, the sheet metal support surface is pivoted (starting from the starting position) into the second of the two pivoting platform positions, this enables or facilitates the rear-side removal of the cut-off workpiece (removal "to the rear").

[0014] The invention is based on the finding that, in particular, the synergistic interaction of the swivel arm and swivel plateau enables a guillotine shear to be produced which enables the removal / dispensing of a cut-off piece of sheet metal from both sides and is characterized by a surprisingly simple and thus equally economical and reliable design.

[0015] Firstly, the sheet support surface can be tilted "forward" (i.e., toward the lower blade) from a (horizontal) starting position by pivoting or tilting it along with the pivoting plateau in a first direction of rotation. To do this, the pivoting plateau is pivoted about the second pivot axis relative to the pivot arm, while the pivot arm remains unchanged relative to the carriage.

[0016] Secondly, the sheet support surface can be tilted backwards (i.e., away from the lower blade) from its horizontal starting position for rear-side workpiece removal. To do this, the swivel arm is pivoted around the first pivot axis in the opposite direction of rotation relative to the carriage, while the swivel plateau remains unchanged in its position relative to the swivel arm.

[0017] To further simplify the rear removal of the cut-off sheet metal piece, it can be advantageous if the sheet metal support surface is pivoted about both pivot axes, starting from the starting position. Starting from the starting position, the pivot arm is pivoted relative to the carriage about the first pivot axis. Subsequently or simultaneously, the pivot plateau is pivoted relative to the pivot arm about the second pivot axis in the opposite direction of rotation. In this way, the sheet metal support surface can be lowered relative to the carriage and, in particular, relative to any sheet metal stop device that may be attached there. The cut-off sheet metal piece can thus be guided under the sheet metal stop device, which can facilitate the rear removal of the sheet metal piece.

[0018] According to a first advantageous embodiment, the sheet holding device comprises - at least one first swivel actuator, by means of which the at least one swivel arm can be swivelled about the first swivel axis relative to the carriage, and - at least one second swivel actuator, by means of which the swivel plateau can be swiveled about the second swivel axis relative to the at least one swivel arm.

[0019] This enables automated operation of the guillotine shears and, in particular, the sheet metal holding device.

[0020] Furthermore, the at least one first swivel actuator and the at least one second swivel actuator are advantageously designed as linear actuators, in particular as pneumatic linear actuators.

[0021] Linear actuators, especially pneumatic linear actuators, are characterized by robustness, cost-effectiveness and easy controllability, which makes them ideal for use in a guillotine shear according to the invention.

[0022] In order to simplify the positioning of the workpiece to be machined, the sheet metal holding device can also comprise a sheet metal stop device attached to the carriage with a movable sheet metal stop.

[0023] According to a further advantageous embodiment, - the at least one swivel arm is pivotable (about the first swivel axis) into a raised (horizontal) swivel arm position and a lowered swivel arm position, and - in particular the raised swivel arm position is limited by at least one upper swivel arm stop and the lowered swivel arm position is limited by at least one lower swivel arm stop.

[0024] In particular, if a pneumatic (linear) actuator is used as the first swivel actuator, the upper swivel arm stop and / or the lower swivel arm stop can be formed by the corresponding end stop of the pneumatic (linear) actuator.

[0025] According to a further preferred embodiment, the guillotine shears additionally have the following features: - the guillotine shear comprises a lower pivoting plateau stop, in particular attached to the machine frame; - the swivel plateau has a first stop region and a second stop region, each of which is designed to come into contact with the lower swivel plateau stop in order to limit further pivoting of the swivel plateau relative to the swivel arm; wherein - when the at least one swivel arm is swivelled into the raised swivel arm position, the first stop region of the swivel plateau (by swivelling the swivel plateau about the second swivel axis) can be brought into contact with the lower swivel plateau stop and thus the swivelling of the swivel plateau relative to the at least one swivel arm can be limited in a first swivel plateau position, and - when the at least one swivel arm is swivelled into the lowered swivel arm position, the second stop region of the swivel plateau (by swivelling the swivel plateau about the second swivel axis) can be brought into contact with the lower swivel plateau stop and thus the swivelling of the swivel plateau relative to the at least one swivel arm can be limited in a second swivel plateau position, and - optionally the lower swivel plateau stop is designed as a roller stop.

[0026] The first swivel plateau position enables or facilitates the front-side removal of the cut workpiece, while the second swivel plateau position enables or facilitates the rear-side removal.

[0027] The lower pivoting plateau stop defines both the first pivoting plateau position and the second pivoting plateau position by interacting with the first stop area of ​​the pivoting plateau and the second stop area. This "dual use" of the lower pivoting plateau stop (for both pivoting plateau positions) enables an extremely simple, robust, and cost-effective design of the guillotine shear.

[0028] The lower pivot plateau stop is preferably designed as a roller stop. A roller stop comprises a rotatably mounted roller which serves as a stop and is in contact with the first or second stop region of the pivot plateau. The use of a roller stop is particularly advantageous when the pivot plateau is in the first pivot plateau position (and thus the first stop region is in contact with the roller stop) and the carriage is moved back and forth between the TDC position and the BDC position. In other words, the carriage is moved between the TDC and BDC positions while the pivot plateau is lowered into the first pivot plateau position. This is because the up and down movement of the carriage continuously changes the exact location within the first stop region at which the pivot plateau is in contact with the roller stop.The rotating roller of the roller stop can compensate and absorb this change in location particularly well.

[0029] Furthermore, the sheet metal support surface can be aligned horizontally in the second pivoting plateau position. This can be particularly advantageous if the workpiece to be removed from the rear is sensitive, for example if it has a sensitive surface and / or is particularly susceptible to scratches or undesired deformation; because the horizontal storage of the workpiece to be removed on the sheet metal support surface can prevent the workpiece from slipping and falling. In order to move from the (horizontal) starting position of the sheet metal support surface to the second pivoting plateau position, the pivoting plateau is pivoted about the first and second pivot axes, each in opposite directions. In the second pivoting plateau position, the sheet metal support surface is thus offset downwards parallel to the carriage compared to the starting position.This “parallel offset” can facilitate the rear removal of the cut workpiece, especially if a sheet metal stop device with a sheet metal stop is provided on the carriage.

[0030] Alternatively, the sheet support surface can be tilted backward (i.e., away from the lower blade) in the second pivoting plateau position. This can be particularly advantageous if the workpiece to be removed from the rear is to slide down following the incline of the sheet support surface.

[0031] According to a further advantageous embodiment of the plate shear according to the invention, it is provided that - the swivel platform comprises a platform frame and a pendulum, - the platform frame is mounted on at least one pivot arm so as to be pivotable about the second pivot axis and forms the first stop area, and - the pendulum is pivotably mounted on the platform frame around a pendulum axis and forms the second stop area.

[0032] It is particularly preferred that - the pendulum can be pivoted by a restoring force into a pendulum starting position in which the pendulum stops at a pendulum stop arranged on the platform frame, - the pendulum can be pivoted against the restoring force (around the pendulum axis) from the pendulum starting position, and - optionally the restoring force is applied by a spring force or a weight force.

[0033] When the guillotine shear is shut down, the swivel actuators may give way uncontrollably, causing the swivel arm and swivel plateau to lower uncontrollably under gravity. If the guillotine shear is then restarted from this uncontrolled lowered state and the swivel actuators are reactivated, raising the swivel arm and swivel plateau, both stop areas of the swivel plateau may come into contact with the lower swivel plateau stop at the same time. If both stop areas are immobile on the swivel plateau, this can lead to unwanted jamming of the swivel plateau and, as a result, damage to the guillotine shear.

[0034] To prevent such jamming, the second stop area, along with the pendulum, can deflect against the restoring force. If, during recommissioning from an uncontrolled lowered position, both stop areas come into contact with the swivel plateau stop simultaneously, the pendulum and the second stop area are pushed to the side against the restoring force.

[0035] According to a further advantageous embodiment of the invention, the guillotine shears additionally have the following features: - the guillotine shear comprises at least one lower swing arm stop, in particular attached to the carriage; - the at least one pivot arm has a third stop region which is designed to come into contact with the at least one lower pivot arm stop in order to limit the pivoting of the at least one pivot arm relative to the carriage in the lowered pivot arm position.

[0036] The precise positioning of at least one lower swivel arm stop, at least one lower swivel plateau stop and the associated stop areas defines the second swivel plateau position and thus determines the alignment of the sheet support surface in this position.

[0037] It can be provided that the lower stops (lower swivel plateau stop, lower swivel arm stops) and / or the associated stop areas (first stop area, second stop area, third stop area) are adjustable in terms of their exact position and / or shape. In this way, for example, a horizontal orientation or a rearward tilted orientation of the sheet support surface can be achieved in the second swivel plateau position by adjusting the respective position of the lower stops and / or the associated stop areas accordingly.

[0038] It can also advantageously be provided that the maximum upward pivoting of the (at least one) swivel arm and the swivel plateau is limited by upper stops. The use of stops enables the use of relatively simple actuators. Because the stops precisely define the relevant positions of the sheet support surface (starting position, first swivel plateau position, second swivel plateau position, raised swivel arm position, lowered swivel arm position), the use of complex and expensive position-controlled or angle-controlled actuators with complex sensor technology for moving the swivel arm and the swivel plateau can be dispensed with.

[0039] According to a further advantageous embodiment of the plate shears according to the invention, it can be provided that - the sheet support surface is formed from several sheet support rails, and optionally - the sheet metal support rails each have at least one (particularly motor-driven) support roller or at least one conveyor belt.

[0040] In this way, the front and / or rear removal of the cut sheet metal piece can be further simplified.

[0041] Free-running rollers allow the cut sheet piece to “slip out” due to gravity, even at very small angles of inclination of the sheet support surface.

[0042] In the following, embodiments of the guillotine shear according to the invention are explained in more detail with reference to the schematic drawings. Fig. 1A-1B a schematic representation of a first embodiment of the plate shear according to the invention in a front view ( Fig. 1A) and a rear view ( Fig. 1B), Fig. 1C is a schematic perspective view of the carriage of the guillotine shear according to the first embodiment, Fig. 2 the first embodiment of the plate shear in a side sectional view according to section BB, Fig. 3A-3C the guillotine shears according to Fig. 2 in a side sectional view in three different operating states during the front output of a cut sheet piece, Fig. 4A-4C the guillotine shears according to Fig. 2 in a side sectional view in three different operating states during the rear output of a cut piece of sheet metal, Fig. 5A-5B a section of the guillotine shears according to the first embodiment in a schematic side view, Fig. 6A-6B the guillotine shears in the side section view according to Fig. 2 in two different operating states when restarting from an uncontrolled lowered machine state, Fig. 7A-7B a second embodiment of a plate shear according to the invention in a side sectional view ( Fig. 7A) and a side view ( Fig. 7B), and Fig. 8 the second embodiment of the plate shear in a side view in a different operating state.

[0043] In some of the figures, individual machine components are hidden and therefore not visible in order to increase the clarity of the representations.

[0044] The Fig. 1A to 2 show the first embodiment of a plate shear according to the invention in a front view ( Fig. 1A), a rear view ( Fig. 1B) and a lateral sectional view ( Fig. 2) in accordance with the Fig. 1B marked cutting line section BB.

[0045] The guillotine shear 1 comprises a machine frame 2 with two vertical frame columns 3 and a horizontal frame base 4. The two frame columns 3 support a table 5 with a lower blade 6 attached thereto. The table 5 forms a table support surface 7 which is aligned with a cutting edge 8 of the lower blade 6.

[0046] By means of a (not visible) drive unit, a carriage 10 can be moved vertically relative to the table 5 (or to the machine frame 2) between a TDC position and a BDC position via a crank drive 9. According to the Fig. 1A, Fig. 1B and Fig. 2 the carriage 10 is in the TDC position.

[0047] The crank drive 9 has a horizontally extending crankshaft 11 which can be rotated by the drive unit and has two eccentrically mounted pin bearings 12 at the ends, each of which is connected to the carriage 10 via a push rod 13.

[0048] In order to collect cut-off sheet metal pieces for front-side removal, the guillotine shear 1 has a sheet metal collecting ramp 14 arranged between the frame columns 3.

[0049] As can be seen in particular from the schematic representation of the carriage 10 in Fig. 1C, the carriage 10 comprises a carriage beam 15 with an upper blade 16, two carriage plates 17 arranged at opposite ends of the carriage beam 15, a sheet metal holding device 18 attached to the carriage plates 17, and a sheet metal stop device 19 attached to the carriage beam 15. The carriage plates 17 are guided linearly in the frame columns 3. The carriage 10, together with all the components arranged or attached thereto, can be moved linearly relative to the machine frame 2.

[0050] With a view to the Fig. 2, the structure of the sheet metal stop device 19 and the sheet metal holding device 18 is described in detail below.

[0051] The sheet metal stop device 19 comprises a horizontal support beam 20 screwed to the carriage beam 15 and a plurality of sheet metal stops 21 displaceable along the support beam 20. For this purpose, the sheet metal stops 21 are arranged parallel to one another on a cross strut 22 which is mounted on the support beam 20 via two retaining fins 23 so as to be linearly displaceable.

[0052] The sheet metal holding device 18 comprises a pivoting plateau 24 with a sheet metal support surface 25, two pivoting arms 26 enclosing the pivoting plateau 24, and two actuator holders 27. The pivoting arms 26 are mounted on the carriage plates 17 for pivoting about a first pivot axis 28. The pivoting plateau 24, together with the sheet metal support surface 25, is in turn mounted on the pivoting arms 26 for pivoting about a second pivot axis 29. The sheet metal support surface 25 can thus be pivoted about both the first pivot axis 28 and the second pivot axis 29. The two pivot axes 28, 29 and the cutting edge 8 of the lower blade 6 are arranged parallel to one another.

[0053] The pivoting of the pivot arms 26 relative to the carriage 10 is achieved by means of two first pivot actuators 30. The two first pivot actuators 30 are designed as pneumatic linear actuators and are each rotatably mounted at their ends on one of the actuator holders 27 and on the respective pivot arm 26. The actuator holders 27 are attached to the carriage plates 17 and firmly connected to them.

[0054] The swivel arms 26 are arranged between a (in the Fig. 2 or Fig. 5A) and a raised horizontal swivel arm position (shown in the Fig. 4B, Fig. 4C or Fig. 5B). The pivoting range of the pivot arms 26 is limited in the raised pivot arm position by upper pivot arm stops and in the lowered pivot arm position by lower pivot arm stops 31.

[0055] The two lower pivot arm stops 31 are each formed as a sheet metal extension 32 of the actuator holder 27. When these sheet metal extensions 32 come into contact with the stop blocks 33 of the pivot arms 26 (see Fig. 5B), further pivoting of the pivot arms 26 is limited. The stop blocks 33 form a stop region of the pivot arms 26, which is referred to as the third stop region in the context of this invention. The exact position of the stop blocks 33 and thus the exact position of the lowered pivot arm position can be adjusted and varied to a certain extent by means of slotted screw connections 34 (see Fig. 5A and Fig. 5B). The upper swivel arm stops are defined by the maximum extension length of the first two swivel actuators 30 and thus by the end stop of the linear actuators.

[0056] The swivel plateau 24 comprises a plateau frame 35 and a plurality of sheet metal support rails 36 arranged parallel to one another, which form the sheet metal support surface 25 (cf. Fig. 2). The pivoting platform 24 is mounted on the pivoting arms 26 via the platform frame 35 so that it can pivot about the second pivot axis 29.

[0057] The pivoting of the pivoting plateau 24 relative to the two pivoting arms 26 is effected by means of a second pivoting actuator 37, which is also designed as a pneumatic linear actuator.

[0058] For this purpose, the second swivel actuator 37 is rotatably mounted on one of the swivel arms 26 and the platform frame 35. To connect the second swivel actuator 37 to this swivel arm 26, this swivel arm 26 has a mounting plate 38 that is firmly connected to the rest of the swivel arm 26.

[0059] Furthermore, the pivoting platform 24 comprises a pendulum 39, which is pivotably mounted about a pendulum axis 40 on the platform frame 35. The pendulum 39 has a pendulum leg 41 and a weight leg 42, which protrude in different directions with respect to the pendulum axis 40 (see also Fig. 7B and Fig. 8). The design of the pendulum 39 results in the weight force of the weight leg 42 acting as a restoring force on the pendulum 39, so that the pendulum leg 41 is in contact with a pendulum stop 43 arranged on the platform frame 35 (is in stop position) and is in a pendulum starting position (see Fig. 2, Fig. 7B and Fig. 8). The pendulum 39 can be pivoted out of the pendulum starting position by overcoming this restoring force by means of a deflection force (see such Fig. 6A and Fig. 6B). After the deflection force is removed, the pendulum 39 is then swung back to its initial position by the restoring force.

[0060] The swivel range of the swivel plateau 24 (relative to the swivel arms 26) is limited by an upper swivel plateau stop and a lower swivel plateau stop 44. The upper swivel plateau stop is defined by the maximum extension length of the second swivel actuator 37.

[0061] In Fig. 2, the swivel plateau 24 and thus the sheet support surface 25 are in a horizontal starting position. The swivel arms 26 are pivoted against the upper swivel arm stops, and at the same time, the swivel plateau 24 is pivoted against the upper swivel plateau stop. The swivel arms 26 are thus in the raised swivel arm position. Furthermore, since the carriage 10 is in the TDC position, the sheet support surface 25 and the table support surface 7 lie in a common plane, which facilitates the positioning of the sheet-shaped workpiece (sheet metal piece) 45 to be machined.

[0062] The lower pivot plate stop 44 is designed as a roller stop 46. The roller stop 46 comprises a roller holder 47 and a roller 48 rotatably mounted on the roller holder 47, which acts as a stop. The roller stop 46 is attached to the machine frame 2 and therefore does not move with the carriage 10 when it is moved between its TDC and BDC positions.

[0063] The lower pivot plateau stop 44, i.e., the roller stop 46, can come into contact with two different stop areas of the plateau frame 35 depending on the pivot arm position: The first stop area 49 of the plateau frame 35 is arranged on a nose extension 50 of the plateau frame 35. The second stop area 51 of the plateau frame is arranged on the pendulum leg 41 of the pendulum 39.

[0064] With reference to the Fig. 3A to 4C, the interaction of the various guillotine shear components during the front and rear discharge of a cut piece of sheet metal (workpiece) 45 is described in more detail below.

[0065] The Fig. 3A to 3C show the plate shear 1 according to the invention according to the Fig. 1A to 2 when cutting and front-side dispensing a workpiece 45 at different times.

[0066] First, the workpiece 45 (sheet metal) to be machined is Fig. 3A. The carriage 10 is in the TDC position, the sheet support surface 25 is in the horizontal starting position, in which the pivot arms 26 and the pivot plateau 24 are pivoted against their respective upper stops. The sheet metal panel 45 extends through the wedge-shaped gap between the upper blade 16 and the lower blade 6 and rests both on the sheet support surface 25 of the sheet support device 19 and on the table support surface 7. In this way, tipping and / or bending of the sheet metal panel 45 can be prevented and the positioning of the sheet metal panel 45 is facilitated. The sheet metal panel 45 is in contact with the sheet stops 21 of the sheet stop device 19, thereby determining the dimensions of the workpiece to be cut off. This operating state is also shown in Fig. 5A is a side view in the opposite direction. There, it is particularly evident that, on the one hand, the stop blocks 33 are not in contact with the sheet metal extensions 32 and, on the other hand, the pendulum leg 41 is not in contact with the roller stop 46.

[0067] The cut is then carried out by moving the carriage 10 together with the upper blade 16, the sheet holding device 18 and the sheet stop device 19 by means of the crank drive 9 and the drive unit from the TDC position to the Fig. 3B shown BDC position. The relative position of the swivel plateau 24 with respect to the carriage 10 has changed compared to Fig. 3A remains unchanged. The cut workpiece 45 rests on the sheet support surface 25.

[0068] In order to discharge the cut workpiece 45 to the front (i.e., the front side), the second swivel actuator 37 is activated and the swivel plateau 24 is lowered while the swivel arms 26 remain in the raised swivel arm position. The swivel plateau 24 is swiveled or lowered until the swivel plateau 24 with its nose extension 50 (i.e., the first stop area 49) comes into contact with the lower swivel plateau stop 44 (i.e., the roller stop 46) and thus in the Fig. 3C. The cut workpiece 45 then slides, following the inclination of the sheet support surface 25, into the sheet collecting ramp 14 (for subsequent manual or mechanical removal).

[0069] The dashed circle 52 indicates that the pendulum leg 41, i.e. the second stop area 51 of the swivel plateau 24, cannot come into contact with the roller stop 46 in this operating state of the guillotine shear 1. This is because when the swivel arms 26 are in the raised swivel arm position, the roller stop 46 is not within the reach of the pendulum leg 41 - regardless of whether the slide 10 is in its TDC position (see Fig. 3A) or UT position (see Fig. 3B). When pivoting the pivoting plateau 24, the pendulum leg 41 thus moves past the roller stop 46 and "misses" it when the pivoting arms 26 are in their raised position, while the nose extension 50 acts as a stop.

[0070] The situation is different, however, if, as in the Fig. 4A to 4C, the guillotine shear 1 according to the invention according to the first embodiment is used for cutting off and discharging a workpiece 45 from the back.

[0071] Fig. Figure 4A shows the guillotine shear 1 according to the invention after a cut has been made (cutting process) and the carriage 10, together with the upper blade 16, the sheet support device 18, and the sheet stop device 19, has been moved from the TDC position to the illustrated BDC position. The pivot arms 26 and the pivot plate 24 are pivoted against their respective upper stops. The cut workpiece 45 rests on the sheet support surface 25.

[0072] Now, however, as in Fig. 4B, the first two swivel actuators 30 are activated, and the swivel arms 26 are swiveled from the raised swivel arm position to the lowered swivel arm position. In this process, the lower swivel arm stops 31 (i.e., the sheet metal extensions 32 of the actuator holders 27) come into contact with the stop blocks 33 of the swivel arms 26.

[0073] Then, as in Fig. 4C, the swivel plateau 24 is lowered relative to the swivel arms 26 and pivoted downwards by means of the second swivel actuator 37. The swivel plateau 24 is lowered until the pendulum leg 41 (i.e., the second stop area 51 of the swivel plateau 24) comes into contact with the roller stop 46 (i.e., the lower swivel plateau stop 44). The swivel plateau 24 is thus in the Fig. 4C. This is because when the swivel arms 26 are each in the lowered swivel arm position and the swivel plateau 24 is then lowered, the roller stop 46 is within the reach of the pendulum leg 41. Thus, when the swivel plateau 24 is pivoted, the pendulum leg 41 (and not the nose extension 50 of the swivel plateau 24) comes into contact with the roller stop 46. This operating state is also shown in Fig. 5B is a side view in the opposite direction. There, it can be seen in particular that, on the one hand, the stop blocks 33 are in contact with the sheet metal extensions 32 and, on the other hand, that the pendulum leg 41 is in contact with the roller stop 46.

[0074] The cut workpiece 45 lies on the sheet support surface 25 and can be passed under the sheet stops 21 at the rear (i.e. according to Fig. 4C to the left) from the plate shear 1. The sheet support surface 25 is in the Fig. 4C shown second swivel plateau position horizontally aligned.

[0075] Based on the Fig. 6A and Fig. 6B, which each represent the first embodiment of the guillotine shear 1, the functioning of the pendulum 39 and the pendulum leg 41 is described in more detail below based on various operating states of the guillotine shear 1. If the guillotine shear 1 is switched off and taken out of operation (for example, at the end of a shift), the swivel actuators 30, 37 may yield in an uncontrolled manner and, as a result, the swivel arms 26 and the swivel plateau 24 may be lowered in an uncontrolled manner. This can occur in particular when simple pneumatic actuators are used. In this case, the situation may arise that, as in Fig. 6A, the roller stop 46 simultaneously contacts both stop areas 49, 51 of the pivot arm 26. The roller stop 46 is thus simultaneously in contact with both the pendulum leg 41 (second stop area 51) and the nose extension 50 of the pivot plateau 24 (first stop area 49).

[0076] If the guillotine shear 1 is now put back into operation from this uncontrolled lowered machine state by reactivating all swivel actuators 30, 37 in order to raise the swivel arms 26 and the swivel plateau 24, and if the pendulum leg 41 were immovably attached to the plateau frame 24, there would be a risk that the pendulum leg 41 would be pressed against the roller stop 46 by means of the second swivel actuator 37, the pendulum leg 41 would thereby "jam" on the roller stop 46 and, as a result, this would lead to overloading and damage to individual components.

[0077] This "jamming" can be prevented by the pivotable mounting of the pendulum leg 41 on the platform frame 35. This is because, upon restarting the machine from an uncontrolled lowered state, the pendulum leg 41, together with the pendulum 39, can simply swing away to the side.

[0078] In the Fig. 7A to 8, a second embodiment of the plate shear 1 according to the invention is outlined, which differs from the first embodiment of the plate shear 1 according to the Fig. 1 to 6C essentially in that the sheet metal support rails 36 have support rollers 52. The sheet metal support surface 25 is formed on the support rollers 52, so that the workpiece 45 to be machined or the cut-off workpiece 45 rests on the support rollers 52. By using the support rollers 52, it can be achieved that a cut-off workpiece 45 rolls down the sheet metal support surface 25 automatically due to gravity and is dispensed, even with a very slight inclination of the sheet metal support surface 25.

[0079] The Fig. 7A and Fig. 7B show the guillotine shear 1 in one and the same operating state in two different views. The carriage 10 of the guillotine shear 1 is in the BDC position. The pivot arms 26 are pivoted into their lowered pivot arm positions. The stop blocks 33 are in contact with the sheet metal extensions 32 of the actuator holders 27. The pivot plateau 24 is pivoted against the upper pivot plateau stop. In this operating state, the roller stop 46 is in contact with neither the first stop area 49 nor the second stop area 51 of the pivot plateau 24. There is a gap between the pendulum leg 41 and the roller stop 46. The pivot plateau 24 is thus in a third pivot plateau position. In the third pivot plateau position, the cut-off workpiece 45 slides over the support rollers 52 of the sheet metal support rails 36 onto a provided sheet metal collection carriage 53.

[0080] Deviating from the provisions in the Fig. 7A and Fig. 7B is according to Fig. 8, the pivoting plateau 24 is now pivoted downward relative to the pivoting arms 26 against the lower pivoting plateau stop 44, i.e., the roller stop 46. The pendulum leg 41 (the second stop area 51 of the pivoting plateau 24) is in contact with the roller stop 46, the lower pivoting plateau stop 44. The pivoting plateau 24 is thus in the second pivoting plateau position and is inclined away from the lower blade 6. The alignment or inclination of the pivoting plateau can be determined and influenced by the precise positioning of the lower stops 31, 44 or the associated stop areas. List of reference symbols 4 guillotine shears 2 machine frame 3 frame columns 4 frame base 5 table 6 lower blades 7 Table support surface 8 Cutting edge of the lower blade 9 Crank drive 10 sleds 11 Crankshaft 12 pin bearings 13 Push rod 14 Sheet metal collection ramp 15 sled beams 16 upper blades 17 slide plates 18 Sheet metal holding device 19 Sheet metal stop device 20 supporting beams 21 sheet metal stops 22 Cross brace 23 holding fins 24 swivel platform 25 sheet support surface 26 swivel arms 27 actuator holders 28 first swivel axis 29 second swivel axis 30 first swivel actuator 31 lower swivel arm stop 32 Sheet metal extension 33 stop blocks 34 slotted screw connections 35 platform frames 36 sheet metal support rails 37 second swivel actuator 38 Mounting plate 39 pendulums 40 swing axle 41 pendulum legs 42 weight legs 43 Pendulum stop 44 lower swivel plateau stop 45 Workpiece (sheet metal piece) 46 roller stop 47 roll holders 48 rolls 49 first stop area 50 Nasal process 51 second stop area 52 support rollers 53 sheet metal collection trucks

Claims

[1] Plate shears (1) for sheet metal processing suitable for the front and rear output of a cut-off piece of sheet metal (45), comprising - a machine frame (2), - a table (5) with a lower knife (6) attached thereto, and - a carriage (10) which can be moved relative to the table (5) by means of a drive unit, with an upper knife (16) attached to the carriage (10) and a sheet holding device (18) attached to the carriage (10), with the following features: - the table (5) forms a table support surface (7) which is aligned with a cutting edge (8) of the lower blade (6); - the carriage (10) together with the upper knife (16) and the sheet holding device (18) can be moved between a TDC position and a BDC position by means of the drive unit, in particular perpendicular to the table support surface (7); - the sheet metal holding device (18) comprises at least one pivoting arm (26) and a pivoting plateau (24) with a sheet metal support surface (25), which is formed in particular from a plurality of sheet metal support rails (36); - the at least one pivot arm (26) is mounted on the carriage (10) so as to be pivotable about a first pivot axis (28) running in particular parallel to the cutting edge (8); - the pivoting plateau (24) together with the sheet support surface (25) is mounted on at least one pivot arm (26) so as to be pivotable about a second pivot axis (29) running in particular parallel to the cutting edge (8), so that the sheet support surface (25) is pivotable both about the first pivot axis (28) and about the second pivot axis (29). [2] Plate shears (1) according to claim 1, wherein the sheet holding device (18) comprises - at least one first pivot actuator (30), by means of which the at least one pivot arm (26) can be pivoted about the first pivot axis (28) relative to the carriage (10), and - at least one second pivot actuator (37), by means of which the pivot plateau (24) can be pivoted about the second pivot axis (29) relative to the at least one pivot arm (26). [3] Plate shears (1) according to claim 2, wherein the at least one first pivot actuator (30) and the at least one second pivot actuator (37) are designed as linear actuators, in particular as pneumatic linear actuators. [4] Plate shears (1) according to one of the preceding claims, wherein the sheet holding device (18) comprises a sheet stop device (19) attached to the carriage (10) with a displaceable sheet stop (21). [5] Plate shears (1) according to one of the preceding claims, wherein - the at least one pivot arm (26) is pivotable about the first pivot axis (28) into a raised pivot arm position and a lowered pivot arm position, and - in particular the raised swivel arm position is limited by at least one upper swivel arm stop and the lowered swivel arm position is limited by at least one lower swivel arm stop (31). [6] Plate shears (1) according to claim 5 having the following features: - the guillotine shear (1) comprises a lower pivoting plateau stop (31), which is mounted in particular on the machine frame (2); - the pivoting plateau (24) has a first stop region (49) and a second stop region (51), each of which is designed to come into contact with the lower pivoting plateau stop (31) in order to limit further pivoting of the pivoting plateau (24) relative to the at least one pivoting arm (26); wherein - when the at least one pivot arm (26) is pivoted into the raised pivot arm position, the first stop region (49) of the pivot plateau (24) can be brought into contact with the lower pivot plateau stop (31) by pivoting the pivot plateau (24) about the second pivot axis (29) and thus the pivoting of the pivot plateau (24) relative to the at least one pivot arm (26) can be limited in a first pivot plateau position, and - when the at least one pivot arm (26) is pivoted into the lowered pivot arm position, the second stop region (51) of the pivot plateau (24) can be brought into contact with the lower pivot plateau stop (31) by pivoting the pivot plateau (24) about the second pivot axis (29) and thus the pivoting of the pivot plateau (24) relative to the at least one pivot arm (26) can be limited in a second pivot plateau position, and - optionally the lower swivel plateau stop (31) is designed as a roller stop (46). [7] Plate shears (1) according to claim 6, wherein the sheet support surface (25) is aligned horizontally or tilted backwards in the second pivoting plateau position. [8] Plate shears (1) according to claim 6 or 7, wherein - the swivel plateau (24) comprises a plateau frame (35) and a pendulum (39), - the platform frame (35) is mounted on at least one pivot arm (26) so as to be pivotable about the second pivot axis (29) and forms the first stop region (49), and - the pendulum (39) is pivotably mounted about a pendulum axis (40) on the platform frame (35) and forms the second stop area (51). [9] Plate shears (1) according to claim 8, wherein - the pendulum (39) can be pivoted by a restoring force into a pendulum starting position in which the pendulum (39) is in abutment against a pendulum stop (43) arranged on the platform frame (35), - the pendulum (39) can be pivoted against the restoring force about the pendulum axis (40) out of the pendulum starting position, and - optionally the restoring force is applied by a spring force or a weight force. [10] Plate shears (1) according to one of claims 5 to 9 having the following features: - the guillotine shear (1) comprises at least one lower pivot arm stop (31), in particular attached to the carriage (10); - the at least one pivot arm (26) has a third stop region which is designed to come into contact with the at least one lower pivot arm stop (31) in order to limit the pivoting of the at least one pivot arm (26) relative to the carriage (10) in the lowered pivot arm position. [11] Plate shears (1) according to one of the preceding claims, wherein - the sheet support surface (25) is formed from several sheet support rails (36), and optionally - the sheet metal support rails (36) each have at least one, in particular motor-driven, support roller (52) or at least one conveyor belt.

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