摘要 |
<p>This invention relates to a pressure reducer of the type having a piston slidable in a cylinder with a piston head in the cylinder cooperating with a resilient packing to subdivide the cylinder into high- and low-pressure chambers. A spring is provided in the high-pressure chamber surrounding the piston rod, and engages at one end a piston rod packing and at the other end a radial projection on the piston rod. The radial projection is spaced axially from the piston head by a distance which is greater than the axial length of the piston head packing, the spring preferably holding the piston at the low-pressure end of the cylinder even in the absence of external spring loading on the piston rod.</p> |