Pis′ton–valve.
A valve consisting of a circular disk, which reciprocates in a cylindrical chamber.
It is sometimes preferred to the slide-valve, as it is readily packed and its friction is less.
a is the cylinder;
b, the steam-pipe, having a belt around the cylinder by which the steam reaches the valve-chamber
c. The valves are on a single rod, and
f f are the eduction passages.
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Piston-valve. |
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Steam-engine and piston-valve. |
In
Fig. 3767, the two piston-valves are on the stem of the piston, and govern the induction and eduction ports, through
[
1719]
which steam is admitted to be conducted from the respective cylinders.
