(under subclass 439) Apparatus in which the geometrical outline (as seen in elevation), made up of the vertically extending structure, the struts and the propelling means, changes in basic configuration as the earth working device is lifted or lowered.
(1) Note. The geometrical outline of the definition is made up of four lines connected by pivot points, so that it will naturally change as the struts are lifted or lowered. This simply change is not included in the definition. The changes contemplated by the definition are brought about by some additional means and are those which occur, for example, when
one of the struts is made of two pivoted or telescopic sections which move relatively while the earth working device is being lifted, or when one of the pivot points is on a link which moves as the earth working device is raised or lowered.
SEE OR SEARCH THIS CLASS, SUBCLASS:
7+, for apparatus having an automatic power control and comprising a mast-type hitch in which one of the struts is pivoted to a yieldable pivot point.
