| 摘要 |
<p>A soil cultivator comprising a supporting frame; means for attachment of said frame to a tractor; a first lever arm pivoted at one end to said frame, a second lever arm pivoted at an intermediate position to the other end of said first lever arm, said second lever arm being provid ed with a first lever arm portion extending downwardly below said intermediate pivot point and having secured thereto a shovel or the like soil working tool, and with a second lever arm portion integral with said first lever arm portion and extending upwardly above said intermediate pivot point, the free end of said second lever arm portion being into sliding engagement with a fixed guide element secured to said support frame, and being urged downwardly along said guide element by spring means, whilst it may be caused to slide upwardly along said guide means in opposition to the force of said spring by effect of the resistance opposed by the soil to the progress of the working tool, so as to only partially lift the working tool with respect to the soil by an amount proportional to the soil resistance encountered, whilst maintaining it at all times into substantial operating and working engagement with the soil.</p> |
