Re: What the heck is a Bellcrank?
Crank it up!

( And re-reading this, I was somehow confused with the ball gears at the tiller, which is a problem of a neighbor's of mine on my mind)
Gear teeth can be had at the end of any lever too, and it would be called a bell crank. Think those old OMC out drives (wait..might be sector gears!)...(I'm heading for Google/Wiki on this..still raining, still bored, still getting old and more stupid)
"
A
bell crank is a type of
crank that changes motion around a 90 degree angle. 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 calling servants in upper class
British households.
The bell crank consists of an "L" shaped crank pivoted where the two arms of the L meet. Moving rods (or ropes) are attached to the ends of the L arms. When one is pulled, the L rotates around the pivot point, pulling on the other arm.
Changing the length of the arms changes the
mechanical advantage of the system. Many applications do not change the direction of motion, but instead to amplify a force "in line", which a bell crank can do in a limited space. There is a tradeoff between range of motion, linearity of motion, and size. The greater the angle traversed by the crank, the more non-linear the motion becomes (the more the motion ratio changes).