Patent ID: 7712345
Filing Date: 2010-05-11
Classification: B21D

Abstract:
1. A main beam fabrication system comprising: a feeder rack adapted to feed a plate material to an auto-forwarding and flattening mechanism; an auto-forwarding and flattening mechanism adapted to flatten the plate material fed by said feeder rack and then to forward the flattened plate material to a punching machine; a punching machine operable to punch the flattened plate material delivered from said auto-forwarding and flattening mechanism to form four rows of punch holes on the flattened plate material; a roller shape-forming machine adapted to ram the plate material punched by said punching machine into a shaped beam having a front wall, two curved sidewalls, and a reinforcing groove formed on a middle part of said front wall and extending along the length of said front wall with two rows of said four rows of punch holes disposed at two opposite lateral sides of said reinforcing groove and the other two rows of said four rows of punch holes respectively disposed at said two curved sidewalls; and a cut-off machine adapted to cut off the shaped beam thus obtained from said roller shape-forming machine into multiple pieces of finished products subject to the desired length; wherein said punching machine comprises an upper mold holder, four upper punching dies arranged in two longitudinal rows on a bottom side of said upper mold holder and adjustable to change the transverse pitch between the two longitudinal rows of said four upper punching dies, a bottom mold holder, and four bottom punching dies arranged in two longitudinal rows on a top side of said bottom mold holder and adjustable to change the transverse pitch between the two longitudinal rows of bottom punching dies; said upper punching dies each comprise a fixed upper die member and an adjustable upper die member, said fixed upper die member comprising a row of punching rods and being fastened to said adjustable upper die member with fastening members, said adjustable upper die member having a sliding groove coupled to a respective sliding rail at said upper mold holder, two locating flanges respectively protruded from front and rear sides thereof and respectively coupled to locating grooves of fixed locating blocks at said upper mold holder, an elongated slot, a lock screw mounted with a washer on a threaded shank thereof and inserted through said elongated slot and threaded into a screw hole on said upper mold holder to lock said adjustable upper die member to said upper mold holder, and a plurality of vertically extending positioning columns each defining a sliding hole; said bottom punching dies each comprise a fixed bottom die member and an adjustable bottom die member, said fixed bottom die member comprising a row of die holes and being fastened to said adjustable bottom die member, said adjustable bottom die member having a connection member fastened thereto with fastening members, and two locating flanges respectively protruded from front and rear sides thereof and respectively coupled to respective locating grooves of respective fixed locating blocks at said bottom mold holder, said connection member having a coupling groove, a control rod inserted through said connection member, said control rod having a block disposed at one end thereof and coupled to the coupling groove of said connection member, a threaded shank threaded through a screw hole on a stop block that is affixed to said bottom mold holder, a first locknut threaded onto said threaded shank and stopped at one side of said stop block, and two second locknuts abutted against each other and threaded onto one end of said threaded shank remote from said stop block and said connection member.