Patent ID: 11858024
Assignee: BCGEN CO., LTD.
Field: Machine tools (Mechanical engineering)
Classification: CPC B  H  Y | IPC B  H

Claim 6:
7. A method for manufacturing a cap plate for a secondary battery, the method comprising the method for manufacturing the safety vent of the cap plate of claim 1, wherein
the material plate supplied in the safety vent forming step is formed of a rectangular material plate having a rectangular periphery and elongated in front and rear directions, a tight protruding part is further formed on a periphery of the upper portion of the lower forming portion so that the periphery of the rectangular material plate comes into close contact with the tight protruding part when the rectangular material plate is forged in the safety vent forming step, a tight protruding part is further formed on a periphery of the upper portion of the lower forming portion so that the periphery of the rectangular material plate comes into close contact with the tight protruding part when the rectangular material plate is forged in the lower surface flattening forming step, and a post-forging forming step further proceeds in which a configuration different from a configuration of the safety vent is formed by operating the press by putting the formed rectangular material plate into a next forging process after the lower surface flattening forming step proceeds.