Internal high pressure forming device and method and corresponding tool system

Abstract

The invention relates to a hydroforming device and a hydroforming process and also to a hydroforming die arrangement. To make it possible to produce even complex three-dimensional sheet-metal shapes while ensuring that the deformation process takes place without disruption, the device comprises a die ( 5 ) which is divided into two die halves ( 5 a , 5 b ) along a die parting plane, the two die halves ( 5 a , 5 b ) forming at least one forming chamber ( 6 ) which can be acted on by a hydrostatic internal pressure (Pi) for forming purposes at a workpiece ( 7 ) which is to be deformed, a die carrier ( 2 ), which for each die half ( 5 a , 5 b ) has at least one die carrier component ( 3, 4 ) assigned to this die half ( 5 a , 5 b ), each pair made up of die carrier component ( 3, 4 ) and die half ( 5 a , 5 b ) being assigned at least one fluid chamber ( 8 ) which is formed from a piston component and a piston-receiving component, and means being provided for producing a hydrostatic fluid chamber pressure (Pa) which is at least equal to the hydrostatic internal pressure (Pi) and, compensating for the hydrostatic internal pressure (Pi), exerts a die-closing force on the two die halves ( 5 a , 5 b ).

1 . Hydroforming device, comprising 
 at least one die ( 5 ,  5 ′) which is divided into two die halves ( 5   a ,  5   b ) along a die parting plane, the two die halves ( 5   a ,  5   b ) forming at least one forming chamber ( 6 ) which can be acted on by a hydrostatic internal pressure (Pi) for forming purposes at a workpiece ( 7 ) which is to be deformed,    a die carrier ( 2 ), which for each die half ( 5   a ,  5   b ) has at least one die carrier component ( 3 ,  4 ) assigned to this die half ( 5   a ,  5   b ),    each pair made up of die carrier component ( 3 ,  4 ) and die half ( 5   a ,  5   b ) being assigned at least one fluid chamber ( 8 ) which is formed from a piston component and a piston-receiving component, and    means being provided for producing a hydrostatic fluid chamber pressure (Pa), which is at least equal to the hydrostatic internal pressure (Pi), in each of the fluid chambers ( 8 ), which fluid chamber pressure, compensating for the hydrostatic internal pressure (Pi), exerts a die-closing force on the two die halves ( 5   a ,  5   b )    wherein in each case a plurality of adjacent fluid chambers ( 8 ) are provided on opposite sides of the die ( 5 ), and wherein the means for producing the hydrostatic fluid chamber pressure (Pa) are configured in such a way that the fluid chambers ( 8 ), partially and/or jointly, can be acted on by an identical or different fluid chamber pressure (Pa).    
     
     
         2 . Device according to  claim 1 , in which at least one pair comprising piston component and associated piston-receiving component is formed by a die carrier component ( 3 ,  4 ) and the associated die half ( 5   a ,  5   b ).  
     
     
         3 . Device according to  claim 1 , in which at least one pair comprising piston component and associated piston-receiving component is formed by two die carrier fixtures ( 3   a ,  3   b ,  4   a ,  4   b ) of the corresponding die carrier component ( 3 ,  4 ).  
     
     
         4 . Device according to  claim 3 , in which, in the case of at least one die carrier component ( 3 ,  4 ), one associated die carrier fixture ( 3   a ,  4   b ) is provided with piston-like projections ( 14 ) in order to form the piston component, and the other die carrier fixture ( 3   b ,  4   a ) is provided with corresponding cavities ( 13 ).  
     
     
         5 . Device according to  claim 4 , in which each pair of cavities ( 13 ) or piston-like projections ( 14 ) in each case encloses a fluid chamber ( 8 ).  
     
     
         6 . Device according to anyone of the preceding claims, in which there are means for guiding the die carrier components ( 3 ,  4 ).  
     
     
         7 . Device according to anyone of the preceding claims, in which fluid chambers ( 8 ) which are respectively assigned to two different die halves ( 5   a ,  5   b ) are arranged opposite one another.  
     
     
         8 . Device according to anyone of the preceding claims, in which each pair comprising piston component and associated piston-receiving component in each case forms a sealing unit which seals off each fluid chamber ( 8 ) in a pressure-tight manner.  
     
     
         9 . Device according to anyone of  claims 1  to  8 , in which the fluid chambers ( 8 ), perpendicular to the piston axis, are each round or oval in cross section.  
     
     
         10 . Device according to anyone of  claims 1  to  8 , in which the fluid chambers ( 8 ), perpendicular to the piston axis, are each triangular or rectangular in cross section.  
     
     
         11 . Device according to anyone of the preceding claims, in which the means for producing the hydrostatic fluid chamber pressure (Pa) are configured in such a way that the fluid chamber pressure (Pa) which is produced in the fluid chambers ( 8 ) located opposite one another is in each case identical.  
     
     
         12 . Device according to anyone of the preceding claims, in which the means for producing the fluid chamber pressure (Pa) are configured in such a way that the forces exerted on the two die halves ( 5   a ,  5   b ) by the fluid chamber pressure (Pa) are oppositely directed and are of equal magnitude.  
     
     
         13 . Device according to anyone of the preceding claims, in which there is a control circuit for controlling the hydrostatic fluid chamber pressure (Pa) as a function of the force exerted on the corresponding die half ( 5   a ,  5   b ).  
     
     
         14 . Device according to anyone of the preceding claims, in which the die carrier ( 2 ) is integrated in a clamping table for clamping the die halves ( 5   a ,  5   b ) in place.  
     
     
         15 . Device according to anyone of the preceding claims, in which between the two die halves ( 5 ′ a ,  5 ′ b ) of the die ( 5 ′), in the die parting plane, there is a forming element ( 5 ′ c ), which together with each of the die halves ( 5 ′ a ,  5 ′ b ), in each case forms a forming chamber ( 6   a ,  6   b ) which can be acted on by a hydrostatic internal pressure for shaping purposes at in each case one workpiece which is to be deformed.  
     
     
         16 . Device according to  claim 15 , in which the forming element ( 5 ′ c ) is of mirror-symmetrical construction with regard to the die parting plane.  
     
     
         17 . Device according to  claim 15  or  16 , in which the forming element ( 5 ′ c ) between the die halves ( 5 ′ a ,  5 ′ b ) is secured to a frame which bears the die carrier ( 2 ).  
     
     
         18 . Device according to  claim 15  or  16 , in which the forming element ( 5 ′ c ) is surrounded in a pressure-tight manner by the die halves ( 5 ′ a ,  5 ′ b ).  
     
     
         19 . Device according to  claim 18 , in which the forming element ( 5 ′ c ) is mounted in a floating position between the two die halves ( 5 ′ a ,  5 ′ b ).  
     
     
         20 . Device according to anyone of  claims 15  to  19 , in which a plurality of dies ( 5 ) are arranged adjacent to one another in a direction which is perpendicular to the die parting plane.  
     
     
         21 . Device according to  claim 20 , in which in the die parting plane of at least one of the dies ( 5 ), there is a forming element ( 5 ′ c ) provided between the respective die halves ( 5 ′ a ,  5 ′ b ), which forming element, together with each of the associated die halves ( 5 ′ a ,  5 ′ b ), in each case forms a forming chamber ( 6   a ,  6   b ) which can be acted on by a hydrostatic internal pressure for shaping purposes at in each case one workpiece which is to be deformed.  
     
     
         22 . Hydroforming device assembly, comprising at least two devices according to anyone of  claims 1  to  21 , which form a functional unit.  
     
     
         23 . Hydroforming die arrangement ( 40 - 70 ), in which a plurality of dies, which are in each case divided into two die halves along a die parting plane, are arranged in a stacked arrangement in a direction which is perpendicular to the die parting planes, 
 in which arrangement, during mounting of the die arrangement ( 40 ,  50 ,  60 ,  70 ) between in each case two adjacent die halves ( 41 - 71 ,  45 - 75 ,  46 - 76 ,  42 - 72 ) together with a workpiece which is to be deformed, a pressure chamber (A), which can be acted on by a hydrostatic internal pressure (Pi) for shaping purposes at the workpiece, is formed by the workpiece and one die half, and a deformation chamber (B) is formed by the workpiece and the other die half; and    the deformation chamber (B) being in fluid communication, via the respectively adjacent die half, with the surroundings of the die arrangement ( 40 - 80 ), so that when pressure is applied to the pressure chamber (A), pressure is prevented from building up in the deformation chamber (B).    
     
     
         24 . Hydroforming die arrangement according to  claim 23 , in which the die half which adjoins the corresponding deformation chamber. (B) has outlet openings ( 101 ,  102 ,  201 ,  202 ,  301 ,  302 ) extending from the surroundings of the die to the corresponding deformation chamber (B).  
     
     
         25 . Hydroforming die arrangement according to  claim 24 , in which the outlet openings ( 101 ,  102 ,  201 ,  202 ,  301 ,  302 ) comprise at least one outlet passage ( 101 ,  201 ) extending parallel to the die parting plane and a plurality of outlet passages ( 102 ,  202 ) arranged perpendicular thereto.  
     
     
         26 . Hydroforming die arrangement according to  claim 23  or  24 , in which the die half ( 300 ) which adjoins the corresponding deformation chamber (B) is divided along the die parting plane at least into two separate components ( 300   a ,  300   b ), which each have outlet openings ( 301 ,  302 ) extending perpendicular to the die parting plane toward the corresponding deformation chamber (B).  
     
     
         27 . Hydroforming die arrangement according to anyone of  claims 23  to  26 , in which the stacked arrangement is such that in each case one die half which in each case forms a deformation chamber (B) with the adjacent workpieces ( 49 - 89 ) and one die half which in each case forms a pressure chamber (A) with the adjacent workpieces ( 49 - 89 ) are arranged adjacently, in an alternating sequence, perpendicular to the die parting plane (FIGS. 10 a ,  10   b ).  
     
     
         28 . Hydroforming die arrangement according to  claim 27 , in which at least one of the die halves which in each case forms a pressure chamber (A) with the adjacent workpieces ( 49 - 89 ) has a fluid passage, which branches off towards the two workpieces ( 49 - 89 ), for applying the hydrostatic internal pressure (Pi) to the pressure chambers (A) (FIG. 10 a ).  
     
     
         29 . Hydroforming die arrangement according to  claim 27  or  28 , in which at least one of the die halves-which in each case forms a pressure chamber (A) with the adjacent workpieces ( 49 - 89 ) has two fluid passages which branch off in opposite directions for independent application of the hydrostatic internal pressure (Pi) to the corresponding pressure chambers (A) (FIG. 10 b ).  
     
     
         30 . Hydroforming die arrangement according to anyone of  claims 23  to  26 , in which the stacked arrangement is such that in each case one pressure chamber (A) and one deformation chamber (B) are formed in an alternating sequence perpendicular to the die parting plane (FIG. 10 c ).  
     
     
         31 . Hydroforming process, in which 
 in at least one die ( 5 ), which is divided into two die halves ( 5   a ,  5   b ) along a die parting plane, at least one forming chamber ( 6 ), which is formed by the die halves ( 5   a ,  5   b ), is acted on by a hydrostatic internal pressure (Pi) for shaping purposes at a workpiece ( 7 ) which is to be deformed, and in which    a hydrostatic fluid chamber pressure (Pa), which is in each case at least equal to the internal pressure (Pi) and, compensating for the hydrostatic internal pressure (Pi), exerts a die-closing force on the two die halves ( 5   a ,  5   b ), is produced in fluid chambers ( 8 ) which are formed from a piston component and a piston-receiving component and are each assigned to one of the die halves ( 5   a ,  5   b )    wherein in each case a plurality of adjacent fluid chambers ( 8 ) on opposite sides of the die ( 5 ) are partially and/or jointly acted on by an identical or different fluid chamber pressure (Pa).    
     
     
         32 . Process according to  claim 31 , in which the hydrostatic fluid chamber pressure (Pa) is controlled as a function of the force which is exerted on the corresponding die half ( 5   a ,  5   b ) by the fluid chamber ( 8 ).  
     
     
         33 . Process according to  claim 31  or  32 , in which, in the die ( 5 ′), two forming chambers ( 6 ′ a ,  6 ′ b ), which are arranged opposite one another and are each formed by in each case one of the die halves ( 5 ′ a ,  5 ′ b ) with a forming element ( 5 ′ c ) arranged in the die parting plane between the two die halves ( 5 ′ a ,  5 ′ b ) of the die ( 5 ′), are simultaneously acted on by a hydrostatic internal pressure.  
     
     
         34 . Process according to  claim 33 , in which the forming element (S′c) is arranged mirror-symmetric-ally with respect to the die parting plane, and the two forming chambers ( 6   a ,  6   b ), in order to form two identical components from workpieces which are in each to be deformed, are simultaneously acted on by an identical hydrostatic internal pressure (Pi).  
     
     
         35 . Process according to  claim 33  or  34 , in which, in a plurality of dies ( 5 ) which are arranged adjacent to one another perpendicular to the respective die parting plane and have forming elements ( 5 ′ c ) provided in the respective die parting plane between the respective die halves ( 5 ′ a ,  5 ′ b ), a plurality of forming chambers, which are in each case formed by in each case one of the die halves ( 5 ′ a ,  5 ′ b ) and one of the forming elements ( 5 ′ c ), are simultaneously acted on by a hydrostatic internal pressure.  
     
     
         36 . Hydroforming process, in which, in a hydroforming die arrangement ( 40 - 70 ) in which a plurality of dies which are in each case divided into two die halves along a die parting plane are arranged in a stacked arrangement in a direction perpendicular to the die parting planes, 
 the die arrangement ( 40 ,  50 ,  60 ,  70 ) is equipped, between in each case two adjacent die halves ( 41 - 71 ,  45 - 75 ,  46 - 76 ,  42 - 72 ), with a workpiece which is to be deformed, so that a pressure chamber (A) is formed by the workpiece and one die half and a deformation chamber (B) is formed by the workpiece and other die half;    each of the pressure chambers is acted on by a hydrostatic internal pressure (Pi) for shaping purposes at the corresponding workpiece; and    when pressure is applied to the pressure chamber (A), a build-up of pressure in the deformation chamber (B) is prevented by means of at least one fluid connection between the respectively adjacent die half and the surroundings of the die arrangement ( 40 - 80 ).