Aiming at the problems of high specificity and low efficiency of vegetable transplanting machine, a substrate block seedling transplanter was designed. Through theoretical calculation and force analysis, the structural parameters of two key components of automatic seedling separation device and planting device are determined. Taking cabbage seedlings with 40 × 40 × 40mm substrate block size as the experimental object, the effects of forward speed, planting frequency, front conveyor belt speed on lodging rate, missing rate and qualified rate were studied by single factor test and three factor three-level orthogonal test. Based on the analysis of the significance and interaction of the experimental data, the best combination of the forward speed of 1.1km/h, the planting frequency of 55 plants / min and the front conveyor belt speed of 0.5km/h was obtained. The verification test of the best combination showed that the average qualified rate of planting was 93.31%, which met the relevant industry standards.

Wear Properties of Wood-plastic Composites Pretreated with a Stearic Acid-palmitic Acid Mixture before Exposure to Degradative Water Conditions

The V-shaped toothed roller cotton stalk puller has a low removal ratio and weak pulling effect. Hence, we constructed a simplified mathematical model of the V-shaped tooth roller stalk puller based on elastic collision theory and simple beam theory and conducted a mechanical analysis based on this model to explore the causes of pulling errors and fractures. Specifically, the V-shaped tooth plates of the machine were optimized in an orthogonal experiment with the rotational speed, cogging angle, and ground clearance as the influencing factors, and the removal ratio as the evaluation index. This experiment was designed to enable analysis of the physical characteristics of cotton stalks, and the forces applied during the pulling process. Additionally, a V-shaped toothed roller-type stalk-pulling test bench was constructed. The results revealed that, unlike the cogging angle, the ground clearance significantly affected the removal ratio. Furthermore, the highest removal ratio (i.e., 97%) was achieved when the ground clearance was −20 mm, the rotational speed was 300 rpm, and the cogging angle was 32.5°. An L₉ (3⁴) orthogonal field experiment was also conducted with the rotational speed, cogging angle, and ground clearance as the influencing factors to investigate their respective influences on the stalk removal ratio. The results revealed that the ground clearance most significantly influenced the ratio, followed by the rotational speed, and cogging angle. The ground clearance and rotational speed of the V-shaped toothed roller were each found to significantly influence the ratio. Furthermore, a ground clearance of −20 mm, rotational speed of 300 r/min, and cogging angle of 25° yielded an average removal ratio of 98.27%. Through this research, the mechanism of toothed roller stalk pulling is further deepened and the toothed series stalk pulling technology provides theoretical support.