1. 
   Bell crank
   Bell' crank` A lever whose two arms form a right angle, or nearly a right angle, having its fulcrum at the apex of the angle. It is used in bell pulls and in changing the direction of bell wires at angles of rooms, etc., and also in machinery.
   Found op http://www.encyclo.co.uk/webster/B/34
   
   
2. 
   Bell crank
   • A lever whose two arms form a right angle, or nearly a right angle, having its fulcrum at the apex of the angle. It is used in bell pulls and in changing the direction of bell wires at angles of rooms, etc., and also in machinery.
   Found op http://thinkexist.com/dictionary/meaning/bell_crank/
   
   
3. 
   Bell-Crank
   In machinery, a bell-crank is a rectangular lever by which the direction of motion is changed through an angle of 90 degrees, and by which its velocity-ratio and range may be altered at pleasure by making the arms of different lengths. It is much employed in. machinery, and is named from its being t...
   Found op http://www.probertencyclopaedia.com/browse/GB.HTM
   
   
4. 
   Bellcrank
   A bell crank is a type of crank that changes motion through an angle. The angle can be any angle from 0 to 360 degrees, although 90 degrees and 180 degrees are common. The name comes from its first use, changing the vertical pull on a rope to a horizontal pull on the striker of a bell, used for cal...
   Found op http://en.wikipedia.org/wiki/Bellcrank
   
   

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