Patent ID: 8770546

Claim:
A ball or half-ball valve with drain-proof mechanism, comprising: a body; an inner side of the body being formed as an approximate round chamber and a through hole communicated to the chamber; a top of the body being formed with an upper penetrating hole and a bottom thereof being formed with a lower penetrating hole; a stem passing through the upper penetrating hole to the chamber; a top end of the stem being connected to an operating unit for driving the stem to rotate; an annular seat received in the through hole; a front end and a rear end of the annular seat having reduced stepped structures; a connecting ring having an inward reduced front end; the connecting ring enclosing a front end of the annular seat and being tightly engaged to an inner wall of the through hole of the body; a gap being formed between the stepped front end of the annular seat and an inner wall of the connecting ring so as to provide elasticity; a first drain-proof ring being an annular ring; a rear end of the first drain-proof ring being a V shape concave recess; in assembly, the first drain-proof ring enclosing an outer wall of the annular seat and a front side thereof resisting against a rear end of the connecting ring; a second drain-proof ring being an annular ring; a front end of the second drain-proof ring being formed as a convex V shape protrusion corresponding to the V shape concave recess of the first drain-proof ring; in assembly, the second drain-proof ring enclosing an outer wall of the annular seat and a front side thereof being engaged to the V shape concave recess of the first drain-proof ring; the second drain-proof ring being elastic; the connecting ring, the first and second drain-proof rings being made of elastic material; an elastic ring enclosing the stepped rear end of the annular seat and resisting against a rear end of the second drain-proof ring; a valve unit being installed to the inner side of the annular seat; the valve unit having an axial hole for receiving the stem; and a cover having a size corresponding to that of the through hole; and the cover being locked to an outer side of the through hole.