Swivel bending machine

Abstract

A swivel bending machine has, in front of a front side of a workpiece holding unit, a support table for workpieces to be bent. A workpiece manipulator picks up workpieces to be bent from at least one table end region and takes the workpieces, in parallel with the longitudinal direction of a bending beam, to a portion in the longitudinal center of the workpiece holding unit. The workpiece manipulator has a first pair of clamping tongs and, spaced apart from the first pair in the longitudinal direction of the bending beam, a second pair of clamping tongs for clamping a workpiece. At least one pair of clamping tongs has a first stop surface for referencing workpiece positioning in relation to the longitudinal direction of the bending beam and a second stop surface for referencing positioning of this workpiece in relation to a depth direction of the swivel bending machine.

1 . A swivel bending machine ( 1 ), comprising
 a machine frame;   a workpiece holding unit ( 3 ) connected with the machine frame with a first clamping tool ( 4 ) and an adjustable second clamping tool ( 5 ) interacting therewith for fixing a workpiece ( 2 ) in a horizontal working plane ( 6 ) in such a way that a workpiece portion ( 7 ) to be bent can protrude beyond the workpiece holding unit ( 3 );   a bending beam ( 8 ) mounted adjustably on the machine frame and connected to an adjusting drive ( 9 ) for bending a workpiece portion ( 7 );   wherein the bending beam ( 8 ) has an approximately C-shaped beam cross section ( 10 ) and two bending tools ( 13 ,  14 ) running opposite to and facing one another with respect to a horizontal center plane ( 11 ) in the longitudinal direction ( 12 ) of the bending beam ( 8 ), between which a workpiece portion ( 7 ) of a workpiece ( 2 ) is insertable;   a support table ( 17 ) for workpieces ( 2 ) to be bent in a region in front of a front side ( 18 ) of the workpiece holding unit ( 3 ), said front side ( 18 ) representing the side of the workpiece holding unit ( 3 ) opposite the bending beam ( 8 ), said support table ( 17 ) having a table length ( 19 ) when measured in parallel to the longitudinal direction ( 12 ) of the bending beam ( 8 ) of more than 1.5 m between its two table end regions ( 20 ,  21 ) and said support table ( 17 ) having a table depth ( 22 ) when measured in parallel to the horizontal working plane ( 6 ) and perpendicularly to the front side ( 18 ) of more than 1.0 m, wherein a depth direction ( 16 ) of the swivel bending machine ( 1 ) is defined by the series arrangement of the support table ( 17 ), the workpiece holding unit ( 3 ), and the bending beam ( 8 );   a workpiece manipulator ( 23 ) which is configured to receive workpieces coming from at least one of the table end regions ( 20 ,  21 ) and place them parallel to the longitudinal direction ( 12 ) of the bending beam ( 8 ) in a section in the region of the longitudinal center ( 24 ) of the workpiece holding unit ( 3 ),   
       wherein 
       the workpiece manipulator ( 23 ) has a first pair of clamping tongs ( 25 ) and, spaced apart from the first pair in the longitudinal direction ( 12 ) of the bending beam ( 8 ), a second pair of clamping tongs ( 26 ) for establishing a clamping connection with respect to a workpiece, 
       and wherein at least one of the two pairs of clamping tongs ( 25 ,  26 ) has a first stop surface ( 27 ,  28 ) for the referencing positioning of a workpiece in relation to the longitudinal direction ( 12 ) of the bending beam ( 8 ) and a second stop surface ( 29 ,  30 ) for referencing positioning of this workpiece in relation to the depth direction ( 16 ) of the swivel bending machine ( 1 ). 
     
     
         2 . The swivel bending machine according to  claim 1 , wherein the workpiece manipulator ( 23 ) is movable into and out of the inner region ( 33 ) of the bending beam ( 8 ) enclosed by the C-shaped beam cross section ( 10 ) by means of a guide arrangement ( 32 ) running parallel to the longitudinal direction ( 12 ) of the bending beam ( 8 ). 
     
     
         3 . The swivel bending machine according to  claim 2 , wherein the workpiece manipulator ( 23 ) is movable beyond at least one longitudinal end ( 34 ) of the first or second clamping tool ( 4 ,  5 ) or the lower or upper bending tool ( 13 ,  14 ) by means of the guide arrangement ( 32 ). 
     
     
         4 . The swivel bending machine according to  claim 1 , wherein the first and the second pair of clamping tongs ( 25 ,  26 ) are each fixed on a translational adjusting axle ( 35 ,  36 ) and these adjusting axles ( 35 ,  36 ) are provided for the controlled positioning of the first and second pair of clamping tongs ( 25 ,  26 ) along the depth direction ( 16 ) of the swivel bending machine ( 1 ). 
     
     
         5 . The swivel bending machine according to  claim 1 , wherein the first and the second pair of clamping tongs ( 25 ,  26 ) each comprise a pneumatically actuable adjusting cylinder ( 37 ,  38 ) for closing the respective pair of clamping tongs ( 25 ,  26 ). 
     
     
         6 . The swivel bending machine according to  claim 5 , wherein the first and the second pair of clamping tongs ( 25 ,  26 ) each have a wedge-shaped, tapering activating section ( 40 ), and wherein an adjusting piston ( 41 ) extendable from the adjusting cylinder ( 37 ,  38 ) is insertable with an expanding effect into the activating section ( 40 ). 
     
     
         7 . The swivel bending machine according to  claim 4 , wherein the first and the second adjusting axles ( 35 ,  36 ) each have an electric motor ( 48 ,  49 ) and each have a threaded spindle ( 50 ,  51 ) coupled with the electric motor ( 48 ,  49 ) for the translational adjustment of the first and second pair of clamping tongs ( 25 ,  26 ). 
     
     
         8 . The swivel bending machine according to  claim 1 , wherein the first or the second pair of clamping tongs ( 25 ,  26 ) or the first and the second pair of clamping tongs ( 25 ,  26 ) are configured to grip a side edge ( 52 ) of a workpiece ( 2 ) which runs parallel to the longitudinal direction ( 12 ) of the bending beam ( 8 ) and is arranged closest to the bending beam ( 8 ). 
     
     
         9 . The swivel bending machine according to  claim 1 , wherein the first stop surface ( 27 ,  28 ), which is provided for referencing a workpiece ( 2 ) in relation to the longitudinal direction ( 12 ) of the bending beam ( 8 ), runs vertically and transversely to the longitudinal direction ( 12 ) of the bending beam ( 8 ) and is positioned outside of a clamping portion ( 53 ,  54 ) of the first and second pair of clamping tongs ( 25 ,  26 ). 
     
     
         10 . The swivel bending machine according to  claim 1 , wherein the first and/or the second pair of clamping tongs ( 25 ,  26 ) comprise(s) a non-pivotable lower support finger ( 42 ,  43 ) and an upper clamping finger ( 44 ,  45 ), which upper clamping finger ( 44 ,  45 ) is, in relation to the lower support finger ( 42 ,  43 ), mounted pivotably around a horizontal pivot axle ( 46 ,  47 ). 
     
     
         11 . The swivel bending machine according to  claim 1 , wherein the workpiece manipulator ( 23 ) is configured such as to only use the first stop surface ( 27 ,  28 ) of one of the two pairs of clamping tongs ( 25 ,  26 ) for referencing a workpiece ( 2 ) in the longitudinal direction ( 12 ) of the bending beam ( 8 ) and to exclusively use the clamping effect of the other of the two pairs of clamping tongs ( 26 ,  25 ) with respect to that workpiece ( 2 ). 
     
     
         12 . The swivel bending machine according to  claim 1 , wherein a supporting body ( 56 ) of an additional manipulator ( 57 ) protrudes from a table level ( 55 ) of the support table ( 17 ) in vertical direction, which additional manipulator ( 57 ) has a rotation stamp ( 58 ) rotatable around a vertical axis for turning workpieces ( 2 ) to be machined around the vertical axis, and wherein the supporting body ( 56 ) protrudes vertically in the longitudinal center ( 24 ) or in the region of the longitudinal center ( 24 ) of the support table ( 17 ).