附录Design of sawing anti-blocking mechanism forno-tillage planter and its cutting mechanismLiao Qingxi1,Gao Huanwen2,Shu Caixia1Abstract: Based on blocking issues of no-tillage planter for dry-land farming in two-crop-a-year region in North of China and shortcomings of anti-blocking mechanism developed, such as higher rotation speed (above 1500 r/min) and bigger power consumption (width power consumption per unit up to 1641.74 kW/m, including traction power), a new sawing anti-blocking mechanism was developed and its cutting mechanism was investigated in this paper. Meanwhile stress distribution of the saw-tooth blade calculated by the ANSYS finity element software showed that the saw-tooth blade would be feasible to cut corn straws. Experimental results in the soil bin showed that: 1)The sawing anti-blocking mechanism with two cutting modes of sustaining and no-sustaining cut could realize an integrated function of cutting and directly throwing by reverse rotation, namely, it could throw straws directly to the rear of the opener by former angle of saw-tooth and thrower; 2)The cutting rate of straws would increase along with the rising of straw moisture and rotation speed, and higher moisture of straws would be of benefit to improving cutting quality; 3)The cutting rate of straws would decrease along with the rising of velocity of vehicle while interval of the moved and fixed blade was determined. And the sawing anti-blocking mechanism had higher cutting quality and lower power consumption without leaky cutting and tearing out with small interval of the moved and fixed blade. Compared with other driving anti-blocking mechanisms, theoretical analysis and experimental results showed that the sawing anti-blocking mechanism had fine cut capability and lower rotation speed (650 r/min) and lower power consumption (power consumption per unit width up to 2.95 kW/m) as well as stronger suitability to different stubbles mulch. Additionally, a new way was found out to improve anti-blocking performance of no-tillage planter.Key words: no-tillage planter; sawing anti-blocking mechanism; cutting mechanism; cutting rate1IntroductionAnti-blocking issue of no-tillage planter had become one of the key factors affecting production efficiency and seeding quality of two-crop-a-year region in North of China. It was because there was a great deal of crop stubbles and crop seeding was started shortly after crop had been harvested, leaving no time for crop stubbles to decay. At present, there are two methods to solve anti-blocking issue of no-tillage: 1) Straws were chopped by the straw chopper before seeding, it would lead to adding working procedure and increase costs of production as well as delaying seeding time; 2) Stubbles were cleared out by driving chopping mechanism fixed on no-tillage planter, such as Strip Wheat Spinning and Furrow Planter made in Hebei Nonghaha Machinery Ltd Corporation and 2BMDF-Corn Strip Chopper made in China Agricultural University1and so on. In practice the driving chopping mechanism had significant effect on antiblocking, but also bigger vibration and noise as well as lower security because straws were chopped at high rotation speed.It was reported that the blade base linear velocity of several main straw chopping mechanisms was between 3756 m/s2, mostly chopping mechanism combined with cutting and striking had higher striking velocity and higher power consumption3, e.g. the blade base linear velocity up to 34 m/s could obtain fine cutting effect for corn straws4, and 24 m/s on rice and wheat straws by supporting pole, respectively5. Even if corn straws were cut by sliding cut with vertical blade, its velocity of cutting one straw, two straws and three straws must be up to 10.3 m/s, 13.6 m/s, 15.8 m/s6, respectively, and had higher power consumption. In a word, because the driving chopping mechanism developed presently had high rotation speed ( above 1500 r/min ) and higher power consumption (width power consumption per unit up to 1641.74 kW/m, including traction power), to decrease rotation speed and power consumption would be urgent in practice.Based on practical problems, the objective in this paper is to find a way to solve the shortcoming that it 64 is difficult for common smooth blade to seize straws and it must run at higher rotation speed, decrease power consumption and improve cutting effect as well as anti-blocking performance of no-tillage planter. Additionally some experiments were done by selecting saw-tooth as cutting blade of no-tillage planter and cutting mechanism of the sawing anti-blocking mechanism was investigated.2Structure and cutting rule of the sawing anti-blocking mechanism2.1Structure and characteristicsThe sawing anti-blocking mechanism was made up of saw-tooth blade, throwing ban device, principal shaft, moved and fixed blade combination, covering shell, opener and working frame as well as transmission system. Sketch of th