Magnetic field characteristics analysis and performance test of seeding element with non-axisymmetric magnetic

Traditional magnetic precision seeding element is a single cylindrical magnet, and it generates axisymmetric magnetic field, therefore the magnetic force that the magnetic powder coated seeds suffered in the symmetrical position is equal, and it's magnetic force deviation is zero. Studies showed that this kind of seeding elements easily adsorbed multiple seed in the symmetrical position, resulting multiple index increased .In order to increase the magnetic force deviation between seeds and reduce the multiple indexes, this paper put forward a new magnetic seeding element which was added a bias magnet in the main magnets, producing non-axisymmetric magnetic field. The magnetic field characteristics of the two kinds of seeding element were analyzed in the seed-metering space by using the method of the magnetic field finite element. The analysis showed that the non-axisymmetric magnetic seeding element can increased the magnetic force deviation in the symmetrical position. The comparison tests of seed-metering performance also showed that the non-axisymmetric magnetic seeding element can significantly reduced the multiple index and reduced 4% compared with the axisymmetric magnetic seeding element.