Free one 2 one cam
The most common type has the follower ride in a slot so that the captive follower produces radial motion with positive positioning without the need for a spring or other mechanism to keep the follower in contact with the control surface.
A face cam of this type generally has only one slot for a follower on each face.
Applications include machine tool drives, such as reciprocating saws, and shift control barrels in sequential transmissions, such as on most modern motorcycles.
A special case of this cam is constant lead, where the position of the follower is linear with rotation, as in a lead screw.
These motions are in a plane radial to the rotation of the record and at angles of 45 degrees to the plane of the disk (normal to the groove faces).
The position of the tone arm was used by some turntables as a control input, such as to turn the unit off or to load the next disk in a stack, but was ignored in simple units.
These diagrams relate angular position, usually in degrees, to the radial displacement experienced at that position.
This is continuous with a tangent to the tip circle.
In designing the cam, the lift and the dwell angle Several key terms are relevant in such a construction of plate cams: 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.
Face cams may also be used to reference a single output to two inputs, typically where one input is rotation of the cam and the other is radial position of the follower. These were once common is mechanical analog computation and special functions in control systems.
A face cam that implements three outputs for a single rotational input is the stereo phonograph, where a relatively constant lead groove guides the stylus and tone arm unit, acting as either a rocker-type (tone arm) or linear (linear tracking turntable) follower, and the stylus alone acting as the follower for two orthogonal outputs to representing the audio signals.