Press system

Abstract

Disclosed is a press system having advantages of preventing a molded product panel from bursting or being torn due to a difference in molding depth caused by a protrusion shape to improve the moldability and marketability of the product panel when press molding is performed on a material panel. An illustrative press system comprises: a lower die punch provided on a bolster and having a lower surface shape of a product panel; a blank holder provided on the outside of the lower die punch and mounted on the bolster through cushion pins; an upper die having an upper surface shape of the product panel, mounted on the slider, and pressing a material panel together with the lower die punch to mold the product panel; and a sub blank holder unit provided inside the lower die punch by performing the molding while holding a portion of the material panel to be molded into a protrusion shape together with the upper die such that a difference in molding depth is compensated when molding is performed.

1 . A press system comprising:
 a lower die punch provided on a bolster and having a lower surface shape of a product panel;   a blank holder provided on the outside of the lower die punch and mounted on the bolster through cushion pins;   an upper die having an upper surface shape of the product panel, mounted on a slider, and configured to press a material panel together with the lower die punch to mold the product panel, a portion of the material panel to be molded into a protrusion shape; and   a sub blank holder unit provided inside the lower die punch and configured to hold the portion of the material panel to be molded into the protrusion shape together with the upper die such that a difference in molding depth is compensated.   
     
     
         2 . The press system of  claim 1 , wherein the sub blank holder unit includes a mount plate mounted on one side of an upper portion of the bolster, a sub blank holder provided inside the lower die punch to be slidable and holding a portion of the material panel, and at least one elastic member provided between the mount plate and the sub blank holder and providing elastic force to the sub blank holder. 
     
     
         3 . The press system of  claim 2 , wherein the elastic member is made of a gas-cylinder-type spring. 
     
     
         4 . The press system of  claim 2 , wherein the elastic member is provided in plural, and the plurality of elastic members are mounted at equal intervals between the mount plate and the sub blank holder. 
     
     
         5 . A method, comprising:
 inserting a material panel on a blank holder between a lower die punch and an upper die, the lower die punch having a lower surface shape of a product panel, the blank holder provided on the outside of the lower die punch, and the upper die having an upper surface shape of the product panel;   pressing the material panel between the upper die and lower die punch to mold the product panel, a portion of the material panel to be molded into a protrusion shape; and   compensating a difference in molding depth between the upper die and lower die punch at the protrusion shape using a sub blank holder unit provided inside the lower die punch and configured to hold the portion of the material panel to be molded into the protrusion shape together with the upper die.   
     
     
         6 . The method of  claim 5 , wherein the sub blank holder unit includes a mount plate mounted on one side of an upper portion of the bolster, a sub blank holder provided inside the lower die punch to be slidable and holding a portion of the material panel, and at least one elastic member provided between the mount plate and the sub blank holder and providing elastic force to the sub blank holder. 
     
     
         7 . The method of  claim 6 , wherein the elastic member is made of a gas-cylinder-type spring. 
     
     
         8 . The method of  claim 6 , wherein the elastic member is provided in plural, and the plurality of elastic members are mounted at equal intervals between the mount plate and the sub blank holder. 
     
     
         9 . A press system comprising:
 a lower die punch having a lower surface shape of a product panel;   a blank holder provided on the outside of the lower die punch;   an upper die having an upper surface shape of the product panel and configured to press a material panel together with the lower die punch to mold the product panel, a portion of the material panel to be molded into a protrusion shape; and   a sub blank holder unit provided inside the lower die punch and configured to hold the portion of the material panel to be molded into the protrusion shape together with the upper die such that a difference in molding depth is compensated.   
     
     
         10 . The press system of  claim 9 , wherein the lower die punch is provided on a bolster, the blank holder is mounted on the bolster, and the upper die is mounted on a slider. 
     
     
         11 . The press system of  claim 10 , wherein the sub blank holder unit includes a mount plate mounted on one side of an upper portion of the bolster, a sub blank holder provided inside the lower die punch to be slidable and holding a portion of the material panel, and at least one elastic member provided between the mount plate and the sub blank holder and providing elastic force to the sub blank holder. 
     
     
         12 . The press system of  claim 11 , wherein the elastic member is made of a gas-cylinder-type spring. 
     
     
         13 . The press system of  claim 11 , wherein the elastic member is provided in plural, and the plurality of elastic members are mounted at equal intervals between the mount plate and the sub blank holder.