| 摘要 |
A precompression valve has a body(314) defining a fluid inlet, a fluid outlet and a fluid passage (373) from the inlet to the outlet. A resiliently deformable valve member (372) is located in the passage. The valve member has a resiliently deformable body (372a) smaller than the bore and a resiliently deformable sealing skirt (388) mounted to part of the body to engage with a sealing surface of the passage to prevent fluid flowing through the passage when the body portion and sealing skirt are both in initial resiliently biased configurations. The valve member body (372a) deforms when subjected to a force causing the sealing skirt (388) deform or move to open a flow path through the valve. During at least part of the deformation of the body, the sealing skirt (388) is deformed and held in the sealing position by the pressure of the fluid acting upon it. The valve is arranged so that when a minimum fluid pressure level is reached, the sealing skirt (388) is moved sufficiently to open a fluid flow path through the valve. As the pressure differential across the sealing skirt equalises, it is then able to at least partially reform to its original shape increasing the area of the fluid flow path. |
