Definition - What does Intake Valve mean?
An Intake Valve is a spring action valve that is placed on a cylinder head of an internal combustion engine just next to the spark plug and exhaust valve. Its main purpose is to allow the proper amount of air-fuel mixture to enter inside the cylinder when the complete movement cycle of piston from TDC (top dead center) to BDC (Bottom Dead Center) and back to TDC takes place.
Petropedia explains Intake Valve
All cars that run on gasoline or diesel make use of a four stroke internal combustion engine. Vehicle manufacturers set the air-fuel mixture intake into the cylinder as per their organization's performance parameter of the engine. When the air fuel mixture enters into the engine via intake valve, it is compressed to great extent. At this point, both the intake and exhaust valves remains closed. The temperature of this mixture when compressed becomes very high and now a small spark is initiated by a spark plug which is enough to start the combustion inside the cylinder. When the combustion happens in the air-fuel mixture, the force generated due to the combustion forces the piston to move to BDC and at this point of time exhaust valve gets open so that exhaust gases can move out. Once all the exhaust gases are out of the cylinder chamber, again the intake valve opens up so as to allow the next set of air-fuel mixture into the chamber. This procedure keeps on repeating till the engine is in power.