Patent ID: 8162456

Claim:
A piercing jig for forming an opening in a cover film welded or bonded to a fluid container in such a manner as to cover a hole formed in the fluid container, the piercing jig comprising a blade body having a distal end that enters a covering area of the cover film that covers the hole when the opening is formed in the cover film, the distal end of the blade body including at least three blade portions extending radially from a single point, wherein the blade portions extend toward a proximal end of the blade body as a radial distance from the single point increases, the piercing jig further comprises a restricting portion that restricts penetration of the blade body with respect to the cover film by contacting a portion of the fluid container when the distal end of the blade body penetrates the cover film, wherein the restricting portion and the blade body are configured to adjust the position of at least one of the restricting portion and the blade body in relation to the other of the restricting portion and the blade body in a penetrating direction of the blade body so as to adjust the penetrating amount of each blade portion of the blade body with respect to the cover film, and the piercing jig further comprises a base body that is removable from the fluid container, wherein the restricting portion and the blade body are provided in the base body.