| 摘要 |
<p>A valve assembly comprising a support body (10), a plunger assembly (11) movable relative to the support body in an axial direction parallel with a longitudinal axis of the plunger assembly and said plunger assembly being angularly movable relative to the support body about said longitudinal axis, seal means (34) to provide a fluid seal between the support body and plunger assembly when support body and plunger assembly are in a first position relative to one another, bias means (43) acting on the plunger assembly in said axial direction to urge the plunger assembly in a first direction relative to the support body towards said first position, a fluid flow passage (28) to allow flow of fluid through the valve assembly when the plunger assembly has been moved relative to the support body away from said first position, said support body and plunger assembly having associated therewith respective abutment surfaces (19,31) engagable with one another to hold the valve assembly in an open state when the plunger assembly has been moved relative to the support body in said axial direction away from said first position to a second position, said plunger assembly being angularly moveable relative to the support body when at said second position selectively to bring the abutment surfaces into mutual engagement to hold the plunger assembly in said second position and to release the plunger assembly for movement towards the first position under the action of the bias means.</p> |
