Engine Valve Assembly

assembly
The action of gathering together as a group for a common purpose
forum: a public facility to meet for open discussion
A group of people gathered together in one place for a common purpose
A group of people elected to make laws or decisions for a particular country or region, esp. the lower legislative house in some US states
a group of machine parts that fit together to form a self-contained unit
fabrication: the act of constructing something (as a piece of machinery)

engine
locomotive: a wheeled vehicle consisting of a self-propelled engine that is used to draw trains along railway tracks
motor that converts thermal energy to mechanical work
A railroad locomotive
A machine with moving parts that converts power into motion
A thing that is the agent or instrument of a particular process
something used to achieve a purpose; "an engine of change"

valve
A membranous fold in a hollow organ or tubular structure, such as a blood vessel or the digestive tract, that maintains the flow of the contents in one direction by closing in response to any pressure from reverse flow
a structure in a hollow organ (like the heart) with a flap to insure one-way flow of fluid through it
A device for controlling the passage of fluid through a pipe or duct, esp. an automatic device allowing movement in one direction only
A cylindrical mechanism in a brass instrument that, when depressed or turned, admits air into different sections of tubing and so extends the range of available notes
device in a brass wind instrument for varying the length of the air column to alter the pitch of a tone
control consisting of a mechanical device for controlling the flow of a fluid