| 摘要 |
A pressurised fluid cylinder (1) having a shut-off valve, comprising a valve element (6) on a valve stem which is linearly movable. A biasing member (15) exerts a biasing force on the valve element and a crank moves the valve stem. The crank comprises a first linkage (37) pivotally attached at one end to the valve stem and a second linkage (50) pivotally attached at one end to the second end of the first linkage and being positionally fixed but rotatable about the opposite end. Rotation of the first linkage (37) in a first rotational direction initially causes biasing of the biasing member and further rotation of the second linkage causes the linkage to pass a top or bottom dead centre position, at which point a proportion of the energy stored in the biasing member during its biasing causes the first linkage to be biased further in the first rotational direction alter the top or bottom dead centre position. |
