PU synchronous belt transmission is composed of a root of tooth surface with spacing within weeks of circular belt and with appropriate match round. It combines belt transmission, chain and gear drive their respective advantages. Turns, with toothed wheel tooth mesh to transmit power. Transmission dragon has accurate synchronous belt transmission ratio, no slip, constant speed ratio can be obtained, is stable and can absorb vibration, low noise, large range of transmission ratio, generally can reach 1:10. Allow the linear velocity can reach 50 m/S, the transfer from a few watts to hundred kilowatts. General can reach 98%, high transmission efficiency, compact structure, and is suitable for multiple spindle drive, without lubrication, no pollution, so there is no pollution and can work in environment is relatively bad places. Transmission products are widely used in textile, machine tools, tobacco, communication cable, light industry, chemical industry, metallurgy, instrument, food, mining, oil, automobile and other industries of various types of mechanical transmission. Arc tooth synchronous belt besides tooth profile for curved shape, the structure and basic same trapezoidal tooth synchronous belt, belt pitch, the depth of tooth, tooth root thickness and fillet radius are larger than the trapezoidal tooth. Toothed after loading, the stress distribution condition is good, smooth the tooth root stress concentration, to improve the carrying capacity of the tooth. So the arc tooth synchronous belt than trapezoidal tooth synchronous belt transmission power is big, and can prevent interference of tooth meshing process. Arc tooth synchronous belt wear-resisting performance is good, little noise at work, without lubrication, can be used for dust environment. Has been in the food, automobile, textile, pharmaceutical, printing, paper and other industries widely used.