A vacuum servo is a component used on
motor vehicle
A motor vehicle, also known as a motorized vehicle, automotive vehicle, automobile, or road vehicle, is a self-propelled land vehicle, commonly wheeled, that does not operate on railway track, rails (such as trains or trams), does not fly (such ...
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 unit, uses a vacuum, usually supplied by the engine, to multiply the driver's pedal effort and apply that effort to the
master cylinder.
Because the servo depends on the vacuum supplied by a running engine, a check valve is typically used in the vacuum line to maintain residual vacuum without engine support, allowing limited use even after parking.
See also
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List of auto parts
This is a list of auto parts, which are manufactured components of automobiles. This list reflects both fossil-fueled cars (using internal combustion engine
An internal combustion engine (ICE or IC engine) is a heat engine in which the c ...
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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