Bevel gear

Bevel gears are gears where the axes of the two shafts intersect and the tooth-bearing faces of the gears themselves are conically shaped. Bevel gears are most often mounted on shafts that are 90 degrees apart, but can be designed to work at other angles as well.[1] The pitch surface of bevel gears is a cone, known as a pitch cone. Bevel gears change the axis of rotation of rotational power delivery and are widely used in mechanical settings.

Bevel gear on roller shutter door.
Regardless of the operating angle, the gear axes must intersect (at a point O)
Bevel gear lifts floodgate by means of central screw.
Bevel ring gear on the rear wheel of a shaft-driven bicycle
Spiral bevel gear
  1. ^ Fred Herbert Colvin; Frank Arthur Stanley (1914). American Machinists' Handbook and Dictionary of Shop Terms: A Reference Book of math Shop and Drawing Room Data, Methods and Definitions. McGraw-Hill book Company, Incorporated. p. 121. Retrieved 14 August 2014.