Development of an auger conveyor type metering device for transplanting of vegetable seedlings raised in paper pots

摘要

An auger type metering mechanism which consisted of an auger type metering device, a seedling delivery tube, a furrow opener, a furrow closer, a power transmission system and a frame was developed for metering of paper pot seedlings for transplanting. The setup was evaluated in simulated field conditions (soil bin) in order to select the operating parameters of the metering device. Evaluation was carried out with pot seedlings of 10-15 cm height at five forward speeds i.e. 1.6, 1.8, 2.0, 2.2 and 2.4 km/h. Data on intra row spacing, angle of inclination of seedling, soil coverage and conveying efficiency (CE), feeding efficiency (FE), transplanting efficiency (TE) and overall efficiency (OE) were determined. The CE, FE, TE and OE were found to be higher than 90% for forward speeds up to 1.6 to 2.0 km/h. Further, the increase in forward speed above 2.0 km/h resulted the FE higher than 90%, however, the TE and OE reduced below 55%. Moreover, increase in the seedling tilting greater than 15% (angle of inclination of seedling >30º from vertical plane) was observed beyond the forward speed of 2.0 km/h. The developed auger type metering mechanism was found to be suitable for metering of vegetable pot seedlings up to the forward speed of 1.6 to 2.0 km/h effectively at a planting rate of 53 to 65 seedlings/min.