Cap device for mixing different kinds of materials separately contained therein and in bottle

A cap device for bottles, comprising:

• a cap body tightened to an externally threaded mouth of a bottle, with a funnel part integrally formed in the cap body to discharge an additive from the cap body into the bottle through a lower end thereof;
• a cap cover assembled with the cap body to cover an open upper end of the cap body while defining a cavity inside both the cap body and the cap cover to contain the additive in the cavity;
• valve means for opening or closing the lower end of the funnel part of the cap body in accordance with a rotating action of the cap body relative to the externally threaded mouth of the bottle;
• wherein the valve means comprises:
• an arc-shaped projection externally formed on a sidewall of the lower end of the funnel part of the cap body at a predetermined portion such that the arc-shaped projection has a predetermined length and a radius of curvature larger than a radius of rotation of the cap body, with the lower end of the funnel part being closed, and the arc-shaped projection being open;
• a breakable sheet attached to the arc-shaped projection to close the open projection;
• and
• a cutting blade projected from an inner surface of a neck of the bottle at a position corresponding to the breakable sheet to break the breakable sheet in accordance with the rotating action of the cap body relative to the externally threaded mouth of the bottle.