Gear is an important part of the mechanical transmission device, in order to ensure the life of the rotating system and operating stability, the gear needs to have a hard surface layer, which can resist wear during operation. For the matrix subjected to alternating loads and impact loads, it is necessary to have sufficient bending strength and toughness to avoid deformation or fracture. Gear manufacturing technology is the key to obtain high-quality gear, gear processing has four stages: tooth blank processing, tooth profile processing, heat treatment and heat treatment finishing. Heat treatment directly determines the internal quality of the gear, tooth profile processing and finishing after heat treatment is the key to manufacturing, but also reflects the manufacturing level of the gear. Today we will take a look at several common methods of tooth surface processing.
1. Hobbing
Hobbing belongs to the generating process, and its working principle is equivalent to the meshing of a pair of helical gears. Gear hob prototype is a spiral gear with a large spiral Angle, because the number of teeth is very small (usually the number of teeth z=1), the teeth are very long, around the shaft to form a worm with a small spiral Angle, and then through the slot and shovel teeth, it becomes a hob with cutting edge and back Angle.
2. Gear shaping
In addition to hobbing, gear shaper is a common cutting process using the generating method. When gear shaper, the gear shaper cutter and the workpiece are equivalent to the meshing of a pair of cylindrical gears. The reciprocating motion of the gear shaper is the main motion of the gear shaper, and the circular motion made by the gear shaper and the workpiece according to a certain proportion is the feed motion of the gear shaper.
3. Gear shaving
In addition to hobbing, gear shaper is a common cutting process using the generating method. When gear shaper, the gear shaper cutter and the workpiece are equivalent to the meshing of a pair of cylindrical gears. The reciprocating motion of the gear shaper is the main motion of the gear shaper, and the circular motion made by the gear shaper and the workpiece according to a certain proportion is the feed motion of the gear shaper.
4. Gear grinding
The cutting motion of gear grinding is similar to that of hobbing, and it is a method of tooth profile finishing, especially for hardened gears, which is often the only finishing method. Gear grinding can be grinding with worm grinding wheel, also can be grinding with conical grinding wheel or disc grinding wheel.