Method and apparatus for folding of sheet materials

Abstract

A method and apparatus for folding of sheet materials for forming a three-dimensional structure from a substantially two-dimensional sheet material includes a restraint assembly for restraining a work piece from movement in one direction, a low flange assembly movably mounted on the frame for biasing the work piece against the restraint assembly and effecting folding along the low-flange fold line, a high flange assembly movably mounted on the frame to effect folding along the high-flange fold line, and a control assembly for sequentially operating the low flange assembly and the high flange assembly. A method of using the method and apparatus for folding of sheet materials, and the structure created thereby, is also disclosed.

1 . A folding tool system for forming a three-dimensional structure from a substantially two-dimensional sheet material which includes a predetermined low-flange fold line defining a low flange and a predetermined high-flange fold line defining a high flange, said system comprising:
 a frame including a restraint assembly for restraining a work piece from movement in one direction;   a low flange assembly movably mounted on the frame for biasing the work piece against the restraint assembly and effecting folding along the low-flange fold line, the low flange assembly including a low-flange applicator for applying force against the low flange to effect low-flange folding;   a high flange assembly movably mounted on the frame to effect folding along the high-flange fold line, the high flange assembly including a high-flange actuator for applying force against the high flange to effect high-flange folding; and   a control assembly for sequentially operating the low flange assembly and the high flange assembly.   
     
     
         2 . A system according to  claim 1 , wherein the restraint assembly includes a restraining block movable between a first position remote from the work piece and a second position for engaging the high flange of the work piece. 
     
     
         3 . A system according to  claim 2 , wherein the restraint assembly further includes a restraining plate movable between a retracted position and an extended position adjacent the low-flange fold line for restraining the work piece as the low flange assembly applies force against the low flange. 
     
     
         4 . A system according to  claim 1 , wherein the low-flange applicator includes an applicator bar to apply substantially continuous force along a majority of the low flange to effect substantially uniform folding along the low-flange fold line. 
     
     
         5 . A system according to  claim 4 , wherein the applicator bar is pivotally mounted to provide over-90° action to accommodate for spring-back of the low flange. 
     
     
         6 . A system according to  claim 1 , wherein the high-flange actuator includes at least one arm pivoting about an axis substantially parallel to an adjacent the high-flange fold line. 
     
     
         7 . A system according to  claim 6 , wherein the arm includes a shoulder corresponding to a desired final shape of the work piece along the high-flange fold line. 
     
     
         8 . A system according to  claim 1 , wherein the control system comprises a controller for controlling the actuation sequence and dwell time of the low flange assembly and the high flange assembly. 
     
     
         9 . A system according to  claim 8 , wherein the control system includes a first pneumatic actuator controlling movement of the low flange assembly and a second pneumatic actuator controlling movement of the high flange assembly. 
     
     
         10 . A system according to  claim 9 , wherein the first pneumatic actuator is an air bag dimensioned and configured to move the low flange assembly upward toward the restraining assembly. 
     
     
         11 . A system according to  claim 9 , wherein the second pneumatic actuator is an pneumatic cylinder dimensioned and configured to move the high flange assembly to pivot along the high-flange fold line. 
     
     
         12 . A system according to  claim 9 , wherein the first pneumatic actuator operates in the range of approximately 50 psi and 150 psi. 
     
     
         13 . A system according to  claim 9 , wherein the second pneumatic actuator operates in the range of approximately 50 psi and 150 psi. 
     
     
         14 . A folding tool system for forming a three-dimensional structure from a two-dimensional sheet material which includes a plurality of predetermined low-flange fold lines defining low flanges, a plurality of predetermined lateral high-flange fold lines defining lateral high flanges, and a plurality of predetermined end high-flange fold lines defining end high flanges, said system comprising:
 a frame including a restraint assembly for restraining a work piece from movement in one direction;   a low flange assembly movably mounted on the frame for biasing the work piece against the restraint assembly and effecting folding along the low-flange fold lines, the low flange assembly including a plurality of low-flange applicators for applying force against the low flanges to effect low-flange folding along each of the low-flange fold lines;   a high flange assembly movably mounted on the frame to effect folding along the high-flange fold lines, the high flange assembly including a plurality of lateral high-flange actuators for applying force against the lateral high flange to effect high-flange folding along each of the lateral high-flange fold lines, the high flange assembly further including a plurality of end high-flange actuators for applying force against the end high flanges to effect high flange folding along each of the end high-flange fold lines; and   a control assembly for sequentially operating the low flange applicators, the lateral high-flange actuators, and the end high-flange actuators.   
     
     
         15 . A system according to  claim 14 , wherein the restraint assembly includes a restraining block movable between a first position remote from the work piece and a second position for engaging the end high flanges. 
     
     
         16 . A system according to  claim 15 , wherein the restraint assembly further includes a restraining plate movable between a retracted position and an extended position adjacent the low-flange fold lines for restraining the work piece as the low flange assembly applies force against the low flanges. 
     
     
         17 . A system according to  claim 14 , wherein the low-flange applicator includes a plurality of applicator bars to apply substantially continuous force along a corresponding one of the low flanges to effect substantially uniform folding along a corresponding one of the low-flange fold lines. 
     
     
         18 . A system according to  claim 17 , wherein the applicator bars are pivotally mounted to provide over-90° action to accommodate for spring-back of the low flanges. 
     
     
         19 . A system according to  claim 14 , wherein the high-flange actuators include at least one arm pivoting about an axis substantially parallel to an adjacent and corresponding one of the high-flange fold lines. 
     
     
         20 . A system according to  claim 19 , wherein the arm includes a shoulder corresponding to a desired final shape of the work piece along the corresponding high-flange fold line. 
     
     
         21 . A system according to  claim 14 , wherein the control system comprises a controller for controlling the actuation sequence and dwell time of the low flange assembly, the lateral high-flange assembly, and the end high-flange assembly. 
     
     
         22 . A system according to  claim 21 , wherein the control system includes a first pneumatic actuator controlling movement of the low flange assembly and a second pneumatic actuator controlling movement of the high flange assembly. 
     
     
         23 . A system according to  claim 22 , wherein the first pneumatic actuator is an air bag dimensioned and configured to move the low flange assembly upward toward the restraining assembly. 
     
     
         24 . A system according to  claim 22 , wherein the second pneumatic actuator includes a plurality of pneumatic cylinders dimensioned and configured to selectively move the lateral high-flange actuators and the end high-flange actuators. 
     
     
         25 . A system according to  claim 22 , wherein the first and second pneumatic actuators operate in the range of approximately 50 psi and 150 psi. 
     
     
         26 . The system according to  claim 1  configured to be operated at force levels selected based on the properties of the work piece, to substantially eliminate the danger of damaging the work piece in the event of operator error. 
     
     
         27 . The system according to  claim 1  configured to be operated at force levels to substantially eliminate the danger of harming a human operator in the event of operator error. 
     
     
         28 . The system according to  claim 1  configured for folding along at least one of the fold lines is achieved by using at least one of the restraint assemblies to contact the work piece at a location proximal to the fold line rather than substantially along the fold line. 
     
     
         29 . The system according to  claim 1  configured to be deployed in an assembly environment, rather than exclusively in a fabrication environment. 
     
     
         30 . A method for forming a three-dimensional structure from an approximately two-dimensional sheet material, the sheet material including a predetermined low-flange fold line defining a low flange and a predetermined high-flange fold line defining a high flange, said method comprising the steps of:
 restraining a work piece from movement in one direction;   positioning a low flange assembly against the low flange to bias the work piece against the restraint assembly, the low flange assembly including a low-flange applicator contacting the low flange to effect folding along the low-flange fold line; and   moving a high flange assembly against the high flange, the high flange assembly including a high-flange actuator contacting the high flange to effect folding along the high-flange fold line.   
     
     
         31 . A method according to  claim 30 , wherein the restraining step is accomplished by moving a restraining block between a first position remote from the work piece and a second position for engaging against one or more high flanges of the work piece. 
     
     
         32 . A method according to  claim 31 , wherein the restraining step is accomplished by moving a restraining plate between a retracted position and an extended position adjacent one or more low-flange fold lines for restraining the work piece as the low flange assembly applies force against the low flanges. 
     
     
         33 . A method according to  claim 31 , wherein the positioning step is accomplished by positioning an applicator bar against one or more low flanges to apply substantially continuous force along a majority of one or more low flanges to effect substantially uniform folding along each corresponding low-flange fold line. 
     
     
         34 . A method according to  claim 33 , wherein positioning step is accomplished by moving the applicator bar to an over-90° position to accommodate for spring-back of the one or more low flanges. 
     
     
         35 . A method according to  claim 31 , wherein the moving step is accomplished by pivoting one or more arms pivoting about a corresponding axis substantially parallel to a corresponding high-flange fold line. 
     
     
         36 . A method according to  claim 31 , wherein the positioning and moving steps are accomplished by providing pneumatic pressure to control positioning of the low flange assembly and movement of the high flange assembly. 
     
     
         37 . A method according to  claim 36 , wherein the provided pneumatic pressure is in the range of approximately 50 psi and 150 psi. 
     
     
         38 . A three-dimensional structure formed by operation of the method of  claim 30 . 
     
     
         39 . The method according to  claim 30  operated at force levels selected based on the properties of the work piece, to substantially eliminate the danger of damaging the work piece in the event of operator error. 
     
     
         40 . The method according to  claim 30  operated at force levels to substantially eliminate the danger of harming a human operator in the event of operator error. 
     
     
         41 . The method according to  claim 30 , wherein folding along at least one of the fold lines is achieved by using at least one of the restraint assemblies to contact the work piece at a location proximal to the fold line rather than substantially along the fold line. 
     
     
         42 . The method according to  claim 30  deployed in an assembly environment, rather than exclusively in a fabrication environment.