Gear transmission is the most widely used and common form of mechanical transmission. The gear uses its teeth to transmit the moment and movement, change the direction of movement, indicate the reading and change the position of the mechanism, etc.
Gear can be divided into involute, cycloid, arc, double arc gear and so on. According to its shape, it can be divided into cylindrical gear,, worm and , drum gear, non-circular gear, etc. According to its transmission form, it can be divided into parallel shaft transmission, intersecting shaft transmission and staggered shaft transmission.
Common materials and mechanical properties of gears
In the process of transmission, the gear teeth should transmit torque and bear bending, impact and other loads. After a period of use, the tooth surface will be worn, pitted, occluded and plastic deformed, which will result in the loss of accuracy, vibration and noise. Different working conditions of gears lead to different failure modes of gears. When selecting, in addition to gear working conditions, the factors such as gear structure shape, production quantity, manufacturing cost and material source should also be considered. Generally, the following basic requirements shall be met:
1,The surface layer of gear teeth shall have enough hardness and wear resistance.
2.For the gear bearing alternating load and impact load, the base should have enough bending strength and toughness.
3.It should have good processability, that is, it should be easy to cut and have good heat treatment performance.
Common methods of tooth profile machining
There are two kinds of machining methods for gear tooth profile: chip machining and cutting machining.
Non chip processing methods include hot rolling, cold extrusion, die forging, precisionand powder metallurgy.
Machining methods can be divided into forming method and generating method.