CAM NOMENCLATURE :
Definitions of terms that used in cam profile nomenclature :
- Base circle :
It is the smallest circle drawn a tangent to the cam profile from the centre.
- Tracepoint :
- Pitch curve :
- Pressure angle :
Pressure angle representing the steepness of the cam profile.
- Pitch point :
- Pitch circle :
- Prime circle :
Displacement diagram :
As a cam rotates about the axis, it imparts a specific motion to the follower which is repeated with each revolution of the cam. It is enough to know the motion of follower for only one revolution.
The motion of the cam can be represented on a graph the x-axis represents the can rotation and the y-axis represents the displacement of the follower. Now we discuss the follower displacement diagram and its terms :
- The angle of ascent :
In the above figure angle of ascent represent by Ɵri.
- The angle of dwell :
It is the angle through which the cam turns at the same time follower remains stationary at the highest or the lowest position.
In figure angle of dwell represent for the highest position by Ɵd1.
- The angle of descent :
In figure angle of descent represent by Ɵre.
- Angle of action :
In figure angle of action represent by Ɵ.
For variation of cam types and different types of followers motions there are also different different displacement diagram are made.