The function of the machine tool main drive gear shift is implemented by changing the position of the gear lathe spindle speed at all levels. CA6140 lathe spindle with a total of 24 level speed. Spindle rotation speed range of 10-1440 r/min, series of 18, reverse speed range is 450 ~ 1400 r/min, the series is 6 level. By manipulation of operating mechanism of sliding gear spindle speed at all levels.
Ⅱ shaft of manipulation is a two gear, with two gears Ⅰ shaft transmission. Ⅲ shaft manipulation is a triple gear, with three Ⅱ shaft gear transmission. Axis II dual sliding gear and shaft III the san sliding gear with a handle on the manipulation .The two gears by changing the position can be achieved six speed. Choose two or three axis control mechanisms dial pin plate CAM with one-piece operating mechanism, this mechanism has simple structure, convenient design, can fully meet the requirements of two or three axis shifting.Ⅳ shaft have two sliding gear to manipulate. Two league slip gear will be manipulation using two sets of operating mechanism. Operating mechanism of gear 4 choice is swinging rod type operating mechanism, this mechanism has simple structure, convenient design, can fully meet the requirements of variable speed. Swinging rod type operating mechanism design need to compute the data has a radius of rocker, rocker shaft axis, the distance between axis to be, the deviation of the slider and swinging Angle of swinging rod.