variable valve actuation

variable valve actuation
In older engines, the intake and exhaust valves operated in a fixed program of timed openings and closings. With variable valve actuation, these actions are varied for a better balance of low-speed, medium-speed, and high-speed operation.

Dictionary of automotive terms. 2015.

Игры ⚽ Поможем сделать НИР

Look at other dictionaries:

  • Variable valve actuation — Variable Valve Actuation, or VVA, is a generalised term used to describe any mechanism or method that can alter the shape or timing of a valve lift event within an internal combustion engine. There are many ways in which this can be achieved,… …   Wikipedia

  • valve actuation — See variable valve actuation …   Dictionary of automotive terms

  • Continuous variable valve timing — offers a unique ability to have independent control of the intake and exhaust valves in an internal combustion engine. For any engine load criteria, the timing of intake and exhaust can be independently programmed [1]. The main variations of… …   Wikipedia

  • Valve timing — In a piston engine, the valve timing is the precise timing of the opening and closing of the valves.In four stroke cycle engines and some two stroke cycle engines, the valve timing is controlled by the camshaft. It can be varied by modifying the… …   Wikipedia

  • valve — A device used to either open or close an opening to allow or prevent the flow of a liquid or gas from one place to another. There are many different types. See ABS relay valve accumultor valve air valve carburetor air control valve air gulp valve …   Dictionary of automotive terms

  • actuation — See variable valve actuation …   Dictionary of automotive terms

  • Desmodromic valve — In general mechanical terms, the word desmodromic is used to refer to mechanisms that have different controls for their actuation in different directions. Desmodromic poppet valve in Ducati engine. A desmodromic valve is a reciprocating engine… …   Wikipedia

  • Overhead valve — OHV redirects here. OHV may also refer to Off highway vehicle. Components of a pushrod valve actuation system …   Wikipedia

  • Poppet valve — A poppet valve is a valve consisting of a hole, usually round or oval, and a tapered plug, usually a disk shape on the end of a shaft also called a valve stem. The shaft guides the plug portion by sliding through a valve guide. In most… …   Wikipedia

  • Homogeneous charge compression ignition — Thermodynamics …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”