System and method for forming a hairpin for motors

1 . A method for forming a hairpin, the method comprising:

unwinding a material coil wound around a bobbin by an unwinder unit;

flattening the material coil supplied from the unwinder unit by flattening rollers;

cutting the material coil supplied from the flattening rollers to a preset length by a feeding unit; and

forming a hairpin having a head portion and a leg portion by

press-molding the material coil of the preset length supplied from the feeding unit by a plurality of forming blocks,

positioning a mold device of a forming unit corresponding to the hairpin to be formed to a home position,

loading the material coil by a plurality of clampers of the mold device,

primarily forming the head portion between an upper forming surface of a first forming block of the forming unit and a lower forming surface of a second forming block of the forming unit by lowering the first forming block while the material coil is disposed between the first forming block and the second forming block,

forming the leg portion between a pair of forming roller units of the forming unit and slant surfaces of the second forming block, and

secondarily forming the head portion between a forming groove formed in the first forming block and a forming protrusion formed in a third forming block of the forming unit after raising the first forming block by a preset distance.

2 . The method of claim 1 , wherein unwinding the material coil comprises:

loading the bobbin on a bobbin loading portion;

releasing the material coil by contacting an unwinder roller to the material coil wound around the bobbin while rotating the bobbin by an operation of a motor connected to the bobbin loading portion; and

discharging the unwound material coil from the bobbin loading portion while being guided by guide bars disposed at respective corners of the bobbin loading portion.

3 . The method of claim 1 , wherein, in cutting the material coil, the preset length is varied by controlling a horizontal position of a cutter of the feeding unit, depending on a specification of the hairpin to be formed.

4 . The method of claim 1 , wherein forming the hairpin having a head portion and a leg portion further comprises detecting a home position of the material coil by a sensing device when the material coil cut into the preset length is supplied to the forming unit.

5 . The method of claim 4 , further comprising, after forming the hairpin:

moving a guide pin of a transfer unit toward the hairpin seated on the second forming block after finishing the forming;

operating the third forming block to push the hairpin toward the guide pin by a forming protrusion of the third forming block; and

loading the hairpin on the guide pin to a guide rail that is arranged in a slanted way.