Vacuum delay valve

A vacuum delay valve is a valve with a small orifice, which delays a vacuum signal. These are commonly used in automobiles to alter the behavior of vacuum switches, vacuum motors, and other vacuum devices.

The engine in a common automobile produces almost 20 inches of vacuum, and this pressure differential has been utilized for everything from automatic locks and windshield wipers to operating emissions control items.

Engine vacuum is also the best direct source of information on the engine's load.

Most delay valves have a one-way function, where there is either no restriction or no movement in one direction.

Delay valves are usually color-coded to their function. ["1988 Jeep Cherokee Technical Service Manual.", "Spark Control System." Chrysler, 1987.]

References


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • vacuum delay valve — (VDV) a valve used by GM to bleed ported vacuum to the vacuum advance unit through a small orifice and control vacuum advance rate. Used to retard or delay the application of a vacuum signal. Also called delay valve …   Dictionary of automotive terms

  • delay valve — A valve used in a vacuum or hydraulic system in which the valve s opening or closing is delayed. Also called vacuum delay valve …   Dictionary of automotive terms

  • vacuum retard delay valve — (VRDV) delays a decrease in vacuum at the distributor vacuum advance unit when the source vacuum decreases. Used to delay release of vacuum from a diaphragm a momentary vacuum trap …   Dictionary of automotive terms

  • spark delay valve — (SDV) a valve in the vacuum advance hose that delays the vacuum to the vacuum advance unit during rapid acceleration from idle or from speeds below 15 mph, and cuts off spark advance immediately on deceleration. Has an internal sintered orifice… …   Dictionary of automotive terms

  • Vacuum switch — Prior to effective engine computers, engine vacuum was used for many functions in an automobile. Vacuum switches were employed to regulate this flow, and were commonly controlled by temperature, solenoids, mechanically, or directly. They operated …   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

  • delay vacuum bypass system — (DVB) an optional system used by Ford that bypasses the spark delay valve during cold operation to improve driveability …   Dictionary of automotive terms

  • Vacuum tube — This article is about the electronic device. For experiments in an evacuated pipe, see free fall. For the transport system, see pneumatic tube. Modern vacuum tubes, mostly miniature style In electronics, a vacuum tube, electron tube (in North… …   Wikipedia

  • Manifold vacuum — Not to be confused with Vacuum manifold. Manifold vacuum, or engine vacuum in an internal combustion engine is the difference in air pressure between the engine s intake manifold and Earth s atmosphere. Manifold vacuum is an effect of a piston s… …   Wikipedia

  • PCV valve — The Positive Crankcase Ventilation valve, or PCV valve, is a one way valve that ensures continual evacuation of gases from inside a gasoline internal combustion engine s crankcase.ExplanationAs an engine runs, gases and combustion pressure are… …   Wikipedia

Share the article and excerpts

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

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.