Abstract: Abstract: Technology of plastic film mulching is widely used in agricultural production because of its advantages of increasing efficiency, inhibiting of weeds, increasing soil humidity, but it is difficult to recycle the plastic film, which lead to the environmental degradation and the restriction of sustainable development of agriculture. Residual film recycling machine of 11-1.7 crankshaft type is the typical residual film recycling machinery which is mainly used for the surface residual film recovery of cotton fiel d after harvest without drip irrigation belt. But the improper operation and unreasonable working parameters lead to the force of pickup tooth is uneven and resistance is large, as a result, pickup tooth are block and bent, the unloading film plate is bent and broken, and the residual film leakage area is large. The core component of crankshaft residual film recycling machine is collecting device of eccentric arc tooth. This paper analyzed the structure and working principle of crankshaft of film recycling machine, established reciprocating eccentric arc tooth movement model of collecting device, analyzed the characteristics of reciprocating eccentric arc tooth movement trajectory and leakage rate. The angular velocity of pickup tooth, the radius of pickup tooth, depth into soil of pickup tooth, speed of residual film recycling machine, effect of different parameter combination on residual film recovery rate and film scraping rate were analyzed and optimized. Field experiment was carried out under optimized parameters. Analysis and test results showed that machine speed, rotating speed of pickup tooth and radius of pickup tooth were mainly influencing factors of film recycling rate. According to theoretical analysis and field experiment, when machine speed and the radius of pickup tooth were fixed value, the higher pickup tooth rotate speed were, the smaller pickup tooth picking up area was, but high speed of pickup tooth exacerbated machine vibration, reduced the service life of machine. The deeper into soil of pickup tooth was, the bigger resistance of roll knife and pickup tooth was, and the higher energy consumption was. Test results showed that at the condition of pickup tooth depth into soil was 35 mm, machine speed was 1.3 m/s, pickup tooth rotation velocity was 60 r/min, radius of pickup tooth was 245 mm, the residual film collecting rate was as high as 93.2%, film scraping rate wss as high as 94.6%, the film leakage pickup rate wss 1.61%. The study provides theoretical basis and reference for the development of residual film recycling machine