Vălve'-gēar or Vălve'-mō'tion, n.

noun

n. (Steam-eng.) The system of parts by which a valve is worked. [For illustration of Slide-valve-gear, see LINK-MOTION.]

☞ The cut shows the puppet-valve-gear. The side-pipe A connects the steam-chests at the opposite ends of the cylinder. The eccentric-hook B oscillates the rock-shaft C, which alternately raises and lowers the valve-stem D and the valve to which it is attached, by means of the wiper E, the toe F, the lifting-rod I, and the lifter K. The valves are worked by hand by means of a starting-bar N and the trip-shaft L.

A labeled diagram of a steam-engine valve gear and its linkage. — Valve-gear.

The illustration depicts a puppet-valve gear and explains how its parts operate the valves. — The cut shows the *puppet-valve-gear*.