Editing Cam (mechanism) (section)

==Disc or plate cam ==
The most commonly used cam is the cam plate (also known as ''disc cam'' or ''radial cam''<ref>{{cite web
| title = Cams; their profiles and the velocity and acceleration of their associated followers
| access-date = 29 August 2013
| url = https://www.codecogs.com/library/engineering/theory_of_machines/cams.php}}</ref>)
which is cut out of a piece of flat metal or plate.<ref>{{cite book
| author = Jensen, Preben w.
| year = 1965
| title = Cam Design and Manufacture
| page = 1
| publisher = The Industrial Press, New York.}}</ref> Here, the follower moves in a plane perpendicular to the axis of rotation of the camshaft.<ref>[https://www.cs.cmu.edu/~rapidproto/mechanisms/chpt6.html Introduction to Mechanisms – Cams] "The follower moves in a plane perpendicular to the axis of rotation of the camshaft."</ref> Several key terms are relevant in such a construction of plate cams: [[base circle (mechanics)|base circle]], prime circle (with [[radius]] equal to the sum of the follower radius and the base circle radius), pitch curve which is the radial curve traced out by applying the radial displacements away from the prime circle across all angles, and the lobe separation angle ('''LSA''' – the angle between two adjacent intake and exhaust cam lobes).

The base circle is the smallest circle that can be drawn to the cam profile.

A once common, but now outdated, application of this type of cam was automatic machine tool programming cams. Each tool movement or operation was controlled directly by one or more cams. Instructions for producing programming cams and cam generation data for the most common makes of machine, were included in engineering references well into the modern [[Numerical control|CNC]] era.<ref>{{cite book | author = Oberg, Erik | year = 1996 | title = Machinery's Handbook, 25th Ed. | publisher = Industrial Press | pages = 1050–1055}}</ref>

This type of cam is used in many simple electromechanical appliances [[Camshaft#Electrical|controllers]], such as dishwashers and clothes washing machines, to actuate mechanical switches that control the various parts.
[[image:Gearbox.jpg|thumb|Motorcycle transmission showing cylindrical cam with three followers. Each follower controls the position of a shift fork.]]