Check valve
From Free net encyclopedia
Image:Clappered.JPG A check valve is a mechanical device, a valve, that normally allows fluid or gas to flow through it in only one direction. A double check valve is often used as a backflow prevention device to keep potentially contaminated water from siphoning back into municipal water supply lines. A clapper valve is a type of check valve used in or with firefighting, and has a hinged gate (often with a spring urging it shut) that will only remain open in the outflowing direction.
Some types of irrigation sprinklers and drip irrigation emitters have small check valves built into them to keep the lines from draining when the system is shut off.
Nikola Tesla invented a deceptively simple one-way valve for fluids in 1920 (U.S. patent # 1,329,559).
In electronics, a diode functions in the same manner.
See also
External links
- A picture of a microscopic checkvalve, a scaled down version of Tesla's original fluidic diode.
- US Patent 1,329,559, Tesla's original fluidic diode (a test of a design showing poor performance)