Gary Bergen,Sylvio Julien Tessier,Tim Strydhorst,James Eichele,Grant Howard Adolph,Ryan Pinfold,Sean Lewis,Leo V. Turko,Larry Beever
申请号：
US13561631
公开号：
US20130112124A1
申请日:
2012.07.30
申请国别(地区):
US
年份:
2013
代理人:
摘要：
A seeder includes a frame on ground wheels defining tool bars for seeding elements spaced across the frame. Each element includes a pair of parallel arms connected to the tool bar bracket forming a parallel linkage for up and down movement of a support arm connected at a rear end and carrying the packer wheel. A spring applies a downward spring force on the parallel linkage to apply a downward force on the packer wheel so that the spring force increases as the parallel arms pivot upwardly and decreases as the parallel arms pivot downwardly. A control device is arranged to raise and lower the tool bar in response to a detected value of a sensor so as to change the angle of the parallel linkage and change the spring force. A cam controlled double rack adjustment of the height of the opener allows the user to change seeding depth.
