equilibrium valve

American  

noun

1. (in a reciprocating engine) a valve opening a passage from one end of a cylinder to the other to equalize pressure upon both faces of the piston.

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Etymology

Origin of equilibrium valve

First recorded in 1870–75

Example Sentences

Q.--Might not an equilibrium valve be so constructed by the interposition of springs, as to enable it to leave the cylinder face when an internal force is applied?

From A Catechism of the Steam Engine by Bourne, John, C.E.

The speed of the engine is controlled by a centrifugal governor and an equilibrium valve.

From Scientific American Supplement, No. 481, March 21, 1885 by Various

A kind of expansion valve, often employed in marine engines of low speed, is the kind used in the Cornish engines, and known as the equilibrium valve.

From A Catechism of the Steam Engine by Bourne, John, C.E.