Adjustable bucket for an earth boring machine

In an earth boring machine for producing a bore in earth formations by breaking away portions of the formations causing the portions of the formations to fall to the bottom of the bore, said machine including a body portion and a rotary head that rotates about a central axis, the improvement comprising:

• a shield positioned above the bottom of the bore over said body portion of the machine extending proximate said rotary head, said shield located at a first radial distance from the central axis of said rotary head;
• a bucket positioned on said rotary head to rotate with said rotary head from a position above the bottom of the bore to a position proximate the bottom of the bore to a position above the bottom of the bore for picking up said portions of the formations at the bottom of the bore;
• and
• means for locating said bucket at substantially said first radial distance from said central axis when said bucket is in said position proximate the bottom of the bore and locating said bucket at a second and shorter radial distance from said central axis when said bucket is in said position above the bottom of the bore, said means comprising a hinge between said bucket and said rotary head, said means including track means in said body portion of said machine for locating said bucket at said first and second radial distances, a cam means connected to said bucket for traveling in said track and a hinge between said bucket and said rotary head.

An earth boring machine for producing a bore by loosening material at the face of the bore wherein the loosened material falls to the bottom of the bore, comprising:

• a machine body;
• a rotary head connected to said machine body, said rotary head having a central axis;
• cutter means on said rotary head for loosening material at the face of the bore;
• a shield positioned above the bottom of the bore over said machine body extending proximate said rotary head, said shield located at a first radial distance from the central axis of said rotary head;
• a multiplicity of buckets connected to said rotary head for picking up the loosened material at the bottom of the bore;
• and
• positioning means for locating said buckets at substantially said first radial distance from the central axis of said rotary head when said buckets are proximate the bottom of the bore and locating said buckets at a second and substantially shorter radial distance from the central axis of said rotary head when said buckets are proximate said shield to allow said buckets to clear said shield, said positioning means including track means in said machine body proximate said rotary head for locating said buckets at said respective first and second radial distances, cams connected to said buckets that travel in said track means and hinge means between said buckets and said rotary head.