Johnson bar
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Revision as of 03:42, 21 November 2006 by 68.116.90.81 (Talk)
A Johnson bar is a hand lever with several distinct positions and a positive clutch to hold the lever in the selected position. The positive clutch is typically activated with a spring-loaded squeeze handle on the lever so that only one hand is needed to release the clutch, move the lever, then reengage the clutch.
Many steam locomotives have valvetrain controls which are set using a Johnson bar.
Many trucks and buses use a hand brake which is controlled with a Johnson bar. These are sometimes called "Johnson bar brakes".
Truck drivers used to call lever controls on air-operated trailer brakes "Johnson bars".
On Caterpillar Tractors the forward / reverse lever is also called a Johnson Bar.
