| 摘要 |
<p>A seed distribution element (1) includes:—a sowing disc (16) rotated by a motor-driven transmission shaft (20)—a housing (10) with a fixed portion (11) in which the shaft (20) is supported and a portion (12) movable relative to the fixed portion and can be closed against it, with a seed collection chamber (15) in the fixed portion (11) and a pneumatic suction chamber (17) in the movable portion (12),—the sowing disc (16) being interposed between the portions (11, 12) and having opposed surfaces (16a, 16b) delimiting the chambers, and provided with a ring of selector holes (23) extending between the opposed surfaces structure for producing a pressure differential between the opposed surfaces in the region of a circumferential segment of the ring of holes, including the pneumatic suction chamber, and—a seal (24) on the movable portion (12) capable of sliding contact with the facing surface (16a) of the disc (16) when the portions are closed against one another,—a thrust-bearing element (26) of the sowing disc (16), supported rotatably in the movable portion (12), to withstand the axial load produced by the disc (16) on the seal (24).</p> |
