| 摘要 |
PROBLEM TO BE SOLVED: To stably form a ball at the tip of a wire while surely preventing oxidation of a lead frame, by installing a linkage path linking a carriage space with the open air around a bonding work window formed in a cover. SOLUTION: As an exhaust path of anti-oxidizing gas supplied to a carriage space 18 of a lead frame 1, a linkage path 21 is installed in addition to a bonding work window 17A. Thereby the exhaust path of gas is dispersed, and a gas spouting amount from the bonding work window 17A can be decreased, without reducing the supply amount of the anti-oxidizing gas. As a result, a flow of gas around a torch electrode 14, in particular, turbulence can be restrained. Thereby a ball 3A of a wire 3 in a fused state during discharge is prevented from being swung by the flow of gas and deformed. It can be avoided that the ball 3A hardens in the swung state or the deformed state as it is and becomes an eccentric ball or a deformed ball. |
