Automobile gear

The composition structure of gears generally includes gear teeth, tooth grooves, end faces, normal surfaces, addendum circles, root circles, base circles, and indexing circles.

Gear teeth are simply called teeth. They are each convex part of the gear used for meshing. These convex parts are generally arranged in a radial manner. The teeth on the paired gear contact each other, which can make the gear continuously mesh; The tooth groove is the space between two adjacent teeth on the gear; The end face is the plane perpendicular to the axis of the gear or worm on the cylindrical gear or worm; Normal surface refers to the plane perpendicular to the tooth line of gear teeth; The addendum circle refers to the circle where the top of the tooth is located; The dedendum circle refers to the circle where the groove bottom is located; The base circle is a circle formed by generating line of involute for pure rolling; The reference circle is the reference circle for calculating the geometric dimensions of the gear in the end face.

Gears can be classified according to tooth shape, gear shape, tooth line shape, tooth surface and manufacturing method.

The tooth profile of a gear includes tooth profile curve, pressure angle, tooth height and modification. The involute gear is relatively easy to manufacture, so the involute gear accounts for the majority of modern gears, while the cycloidal gear and circular arc gear are seldom used.

In terms of pressure angle, the bearing capacity of small pressure angle gear is small; However, the gear with large pressure angle has a higher bearing capacity, but the bearing load increases when the transmission torque is the same, so it is only used in special cases. The tooth height of gear has been standardized, and the standard tooth height is generally adopted. Modified gear has many advantages, and has been widely used in all kinds of mechanical equipment.