| 摘要 |
PCT No. PCT/FI95/00488 Sec. 371 Date Mar. 6, 1997 Sec. 102(e) Date Mar. 6, 1997 PCT Filed Sep. 8, 1995 PCT Pub. No. WO96/07307 PCT Pub. Date Mar. 14, 1996A method and apparatus for sowing seeds using compressed-air pulses is provided. The apparatus includes a seed supply, a compressed-air duct extending to a sowing site, a compressed-air pulse producer for sending compressed-air pulses through the duct, and a seed dispenser communicating with the seed supply and the duct. The seed dispenser includes a reciprocating piston having an adjustable seed amount metering space for receiving a quantity of seeds from the seed supply. The piston is also biased toward the duct and has a depressible portion communicating with the duct. The piston moves toward a loading position when a compressed-air pulse exerts pressure against the depressible portion and returns toward a dispensing position in the absence of a compressed-air pulse exerting pressure against the depressible portion, the metering space communicating with the seed supply when the piston is in the loading position and the metering space communicating with the duct when the piston is in the dispensing position. |
