| 摘要 |
PURPOSE:To prevent the backward flow of stones on a ladder chain by providing a specific rotary screen and a rotary conveyer in the rear side of the ladder chain having a limited soil screening action. CONSTITUTION:In a ladder chain 3 to be provided in the rear side of the excavated blade 2 of a machine body 1, a large number of placing plates 33 are provided between two lanes of chains 32 by mutually lapping or aligning in parallel densely their front and rear end edges. Also, in the rotary screen 4 in the rear of the chain 3, its axis as a rotary shaft is formed in the before and behind directions of the machine body 1, its rear side is formed into a small- diameter conical cage shape, its inside is provided with a spiral rake-up blade 40 formed of linear levers into a screen shape, and the rotary conveyer 5 in its rear side is formed by arranging large numbers of rake-up blades 51 annularly on the inner wall of the freely rotatable cage-shaped ring 50. By this, the backward flow of stones B can be prevented by soil and the stones are separated by the rotary screen 4 and sent out by the conveyer 5. |
