A crown wheel is a wheel with cogs or teeth set at right angles to its plane. The internal diameter of a crown wheel is ground by holding the component in pitch like chucks to ensure accuracy of the finished gear
As a result of the development of "flat" crown wheels it has become possible to construct a special gearbox. IHC has used these new gearwheels to produce a prototype of a continuously variable speed gearbox.
Applications
Crown wheels are used in motorcycle automotive gearboxes. It is also used in mechanical clocks. The clock consists of a crown wheel, rotated by a falling weight, whose teeth drive the pallets of a verge backward and forward. This verge is connected to an arm with a hammer on the end that struck the bell.