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:
“Marriages will survive despite enormous strains. A lover will ask, “Is he happy? Can he still love her?” They don’t realise that’s not the point, it’s all the normal things they do together—going to the supermarket, choosing wallpaper, doing things with the children.”
—Carol Clewlow (b. 1947)
“Have you ever been up in your plane at night, alone, somewhere, 20,000 feet above the ocean?... Did you ever hear music up there?... It’s the music a man’s spirit sings to his heart, when the earth’s far away and there isn’t any more fear. It’s the high, fine, beautiful sound of an earth-bound creature who grew wings and flew up high and looked straight into the face of the future. And caught, just for an instant, the unbelievable vision of a free man in a free world.”
—Dalton Trumbo (1905–1976)