A vacuum servo is a component used on
motor vehicle
A motor vehicle, also known as motorized vehicle or automotive vehicle, is a self-propelled land vehicle, commonly wheeled, that does not operate on rails (such as trains or trams) and is used for the transportation of people or cargo.
The ...
s in their
braking system, to provide assistance to the driver by decreasing the braking effort. In the US it is commonly called a brake booster.
A vacuum servo also known as a power booster or
power brake
Power brakes are a system of hydraulics used to slow down or stop most motor vehicles. It uses a combination of mechanical components to multiply the force applied to the brake pedal by the driver into enough force to actuate the brakes and stop ...
unit uses a vacuum to multiply the drivers pedal effort and apply that effort to the
master cylinder.
It can not be used when the engine is off, mostly after a few attempts.
Notes
External links
What is a brake booster?
(a 4-page basic tutorial article, with illustrations & animation) at HowStuffWorks.com
Brakes
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