双腔侧充种式水稻精量穴播排种器的设计与试验.

In order to realize field precision seeding and raise the utilization of seeding machine, a kind of double-cavity side-filled precision seed metering device for rice was designed, and a new seed-retaining structure was proposed, which used the brush to clean and protect seeds. The working principle seed metering device was analyzed and the related parameters were established. Qualification ratio, resowing ratio, missed seeding ratio and breaking ratio were regarded as the evaluation index. The study objects were "Peizataifeng" (hybrid rice) and "Huanghuazhan" (conventional rice), which were pre-germinated and their moisture were respectively 22.47% (wet basis) and 21.66% (wet basis). The single cavity of seed metering device was used to seed the hybrid rice and the double cavities of seed metering device were used to seed conventional rice with the different rotational speed of seeding axle, the different forward speed of conveyor belt, and the regular throwing-seed height. The experimental results showed there existed optimal combination parameters for the capability of the metering device to meet the needs of precision seeding, which were that the rotational speed of seeding axle was 25 r/min, the forward speed of conveyor belt was 1.0 m/s, the hole distance was 150 mm, the throwing-seed height was 150 mm, the angle between the type hole central line and the seeding disc axis line was 20°, and the angle between the radial direction of long axis for the section of type hole and the radial direction along the end face of the seeding disc was 90°. under the optimal combination parameters, the qualification ratio (2-4 seeds per hole) of seeding "Peizataifeng" (hybrid rice) with single cavity was 87.04%, the resowing ratio (0-1 seed per hole) was 2.96%, the cavity ratio (0 seed per hole) was 3.33%, and the breaking ratio was 0.40%. Meanwhile, the qualification ratio (5-8 seeds per hole) of seeding "Huanghuazhan" (conventional rice) with double cavities was 70.26%, the resowing ratio (0-4 seeds per hole) was 0, the cavity ratio (0 seed per hole) was 0, and the breaking ratio was 0.06%. The single cavity and the double cavities of seed metering device to seed different rice type, the change trends of the qualification ratio, the resowing ratio, the missed seeding ratio and the breaking ratio were consistent. The experimental results showed that the qualification ratio (2-4 seeds per hole) of seeding "Huanghuazhan" was more than 84.13%, the cavity ratio (0 seed per hole) was less than 3.33%, and the breaking ratio was less than 0.47%, when the rotation speed of seeding axle ranged from 10 to 25 r/min. Because the seed metering device has a double-cavity structure, it can seed with single cavity or double cavities, and the adjustment of seeding quantity is convenient. The study provides a basis for the design of double-cavity type seed metering device. [ABSTRACT FROM AUTHOR]