Parallel shaft gear transmission, including cylindrical spur gear, helical gear transmission, spur rack and helical rack transmission, etc. Used for parallel shaft transmission with spur and helical cylindrical gears; spur and helical internal gears; spur and helical gears. These gears are generally called “plane gears”.
Intersecting shaft gear transmission, including straight bevel gear, helical gear, spiral bevel gear, straight tooth surface gear, circular arc gear transmission, etc.
Cross-axis gear transmission, including helical gear transmission, worm gear transmission gear, hyperbolic gear and hypoid gear, etc. These gears are usually called “space gears”.