The invention discloses a continuous
hobbing method for a straight
bevel gear. The continuous
hobbing method is based on a special
hypocycloid approximating a straight line. A cutterhead rotates at the speed being
omega t, a gear rotates at the speed being
omega g, and at the moment, relative movement of the gear and a cutter is equivalent to pure rolling engagement movement of cutter rolling and gear rolling. When the rolling
radius and the reference
radius of the cutter are the same or equal to one half of the gear rolling
radius, the track formed by cutter noses of cutter teeth on the gear is an approximate straight line, and therefore the cutter and the gear can be used for continuous
hobbing of the straight
bevel gear. The continuous hobbing method has the advantages that the continuous hobbing technology is adopted, and therefore production efficiency and precision are high; both wet hobbing and dry hobbing can be achieved, the dry hobbing efficiency is higher, the
tooth surface finish degree is better, the requirement for the cutter and a
machine tool is higher, and wet hobbing just gets the opposite results; the machined straight
bevel gear is in a slight drum shape instead of a strict straight line shape in the
tooth length direction. The drum-shaped size can be controlled by adjusting
machine tool parameters, so that the contact area of the gear is changed to enable the gear to have the better
transmission performance, and gears with constant-depth teeth and shrinkage teeth can be machined.