A normal plane is normal to a tooth surface at a pitch point, and perpendicular to the pitch plane. In a helical rack, a normal plane is normal to all the teeth it intersects. In a helical gear, however, a plane can be normal to only one tooth at a point lying in the plane surface. At such a point, the normal plane contains the line normal to the tooth surface.
Important positions of a normal plane in tooth measurement and tool design of helical teeth and worm threads are:
- the plane normal to the pitch helix at side of tooth;
- the plane normal to the pitch helix at center of tooth;
- the plane normal to the pitch helix at center of space between two teeth
In a spiral bevel gear, one of the positions of a normal plane is at a mean point and the plane is normal to the tooth trace.
Read more about this topic: List Of Gear Nomenclature
Famous quotes containing the words normal and/or plane:
“Dada doubts everything. Dada is an armadillo. Everything is Dada, too. Beware of Dada. Anti-dadaism is a disease: selfkleptomania, man’s normal condition, is Dada. But the real dadas are against Dada.”
—Tristan Tzara (1896–1963)
“Even though I had let them choose their own socks since babyhood, I was only beginning to learn to trust their adult judgment.. . . I had a sensation very much like the moment in an airplane when you realize that even if you stop holding the plane up by gripping the arms of your seat until your knuckles show white, the plane will stay up by itself. . . . To detach myself from my children . . . I had to achieve a condition which might be called loving objectivity.”
—Anonymous Parent of Adult Children. Ourselves and Our Children, by Boston Women’s Health Book Collective, ch. 5 (1978)