Self-opening cap mechanism

A vessel and cap combination, comprising:

• a vessel body having a surface with a stopper block, having a vessel-side rib around a portion of said vessel body with two protruding engagement pieces extending outwardly from said vessel-side rib, a push piece with hook-side portions having hooks facing against said protruding engagement pieces respectively at positions outwardly from said protruding engagement pieces to define a locked position, said push piece being disposed for oscillating in the vertical direction around a supporting position for moving to a released position;
• a cap having a notch section defining a clearance with two engagement pieces formed in a region of said clearance, and having a circular cap-side rib formed at a position inwardly from said engagement pieces with a small clearance therefrom;
• a hinge coupling said vessel body to said cap;
• an elastic member with the base section fixed to said vessel body on an inward side of said hinge, said elastic member having a tip section extending to a surface inside said cap, said elastic member being deformed with said stopper block to a S-shaped form when said cap is closed.

A container, comprising:

• a vessel body having a stopper block and a vessel-side rib around a portion of said vessel body with a protruding engagement piece extending outwardly from said vessel-side rib, said vessel body having a push piece with a hook facing against said protruding engagement piece at a position outwardly from said protruding engagement piece to define a locked position, said push piece being disposed for moving with respect to a supporting position for moving from said locked position to a released position;
• a cap having a cap engagement piece and having a cap-side rib formed at a position inwardly from said cap engagement piece with a small clearance therefrom;
• a hinge connecting said vessel body to said cap;
• an elastic member with a base section disposed relative said vessel body and having a tip section extending to a surface inside said cap, said elastic member being in contact with said stopper block to bend when said cap is closed.