Patent ID: 8550432

Claim:
A stopcock comprising: a housing comprising a first upper surface and a first lower surface opposite to the first upper surface, the housing defining a first hole in the first upper surface, the first hole having a first bottom surface, the housing defining a through hole in the first bottom surface and extending through the first lower surface, the first hole continuously tapering from the first bottom surface to the first upper surface, the through hole continuously tapering from the first lower surface to the first bottom surface, a dimension of the first hole adjacent to the first bottom surface being greater than a dimension of the through hole adjacent to the first bottom surface, thereby forming a step between the first hole and the through hole; and a sealing insert comprising a first engaging portion and a second engaging portion connected to the first engaging portion, the first engaging portion being engagingly received in the first hole, the second engaging portion being engagingly received in the through hole, the sealing insert defining an annular slot between the first engaging portion and the second engaging portion, the annular slot having a first annular portion and a second annular portion communicating with each other, the first engaging portion comprising a main body and an elastic engaging sleeve surrounding the main body with the first annular portion intervening therebetween, the second annular portion surrounding the second engaging portion, the engaging sleeve being shaped to conform to the first hole and flexible toward the main body, the engaging sleeve comprising a second bottom surface exposed at the second annular portion, the engaging sleeve engaging with the step.