Post hole digger

A tractor mounted drill assembly for attachment to the tractor comprising:

• a frame assembly;
• means for mounting said frame assembly to the tractor in a user-selectable vertical displacement of said frame from a ground supporting surface;
• a boom assembly comprising first and second bipartite booms each having a first boom arm having a free proximal end and a second boom arm at an angle relative to said first boom arm having a free distal end, each boom pivotally mounted at a proximal end of said first boom arm to said frame assembly in a laterally spaced-apart relationship, said second boom arm being shorter than said first boom arm and having a starting position generally parallel to a ground surface therebelow;
• a strut extending between said booms at said distal ends of said second boom arms;
• means for swingably mounting the drill assembly to said strut;
• and
• means extending between said boom assembly and said frame for pivoting said boom assembly and drill assembly attached thereto between ground displaced and ground penetrating positions.

For use with a tractor having a three-point hitch, a mainframe assembly for a tool assembly and attachment to said three-point hitch, said mainframe assembly comprising:

• first and second laterally spaced-apart legs, each leg attached to the three-point hitch;
• a strut extending between said legs;
• a central arm having one end connected to said strut and the other end to the three-point hitch;
• at least one side arm assembly having one end attached to said central arm and said other end attached to said mainframe,
• each side arm assembly comprising:
• a housing including said end attached to said central arm;
• an aperture in said housing;
• an arm slidable within said housing and having said other end attached to one of said legs of said mainframe;
• a plurality of apertures along said slidable arm;
• a pin for extension through said aperture in said housing and an aligned aperture in said slidable arm, whereupon extension and retraction of said slidable arm relative to said housing raises or lowers the attached mainframe and the tool assembly attached thereto relative to the underlying ground.