Generally, there are gear teeth, tooth grooves, end faces, normal faces, addendum circles, tooth root circles, base circles, and index circles.
Gear teeth
Referred to as tooth, it is each convex part of the gear used for meshing. These convex parts are generally arranged in a radial pattern. The gear teeth on the mating gear contact each other, which can make the gear continue to mesh and run.
Cogging
It is the space between two adjacent gear teeth on the gear; the end face is on the cylindrical gear or cylindrical worm, and the plane perpendicular to the axis of the gear or worm.
End face
It is the plane on both ends of the gear.
Dharma
Refers to the plane perpendicular to the tooth line of the gear.
Addendum circle
Refers to the circle where the tip of the tooth is located.
Tooth root circle
Refers to the circle where the bottom of the groove is located.
Base circle
The generating line forming the involute is a purely rolling circle.
Index circle
It is the reference circle for calculating the geometric dimensions of the gear in the end face
