Tool control system for agricultural seeders

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.

主权项

1. An agricultural seeder comprising:
a frame having at least one tool bar; ground wheels for supporting the frame for transportation in a direction of working movement across ground to be seeded; a plurality of seeding elements each including a bracket mounted on the tool bar of the frame so that the seeding elements are arranged at spaced positions across the width of the frame for applying seeds to the ground as the frame is moved across the ground; each seeding element including a ground opener for cutting a furrow into the surface of the ground; each seeding element including a packer wheel behind the ground opener for rolling along the ground at least partly in the furrow mounted in a set relationship to the ground opener; each seeding element being mounted on the tool bar for up and down floating movement relative to the frame independently of the other seeding elements; and a sensing system for providing an output signal indicative of a depth of penetration of the packer wheel of at least one of the seeding elements from a surface of the ground as the depth of penetration changes due to changes in soil conditions.