Excavation apparatus and method

Apparatus for loading and initiating delay type percussion initiatable explosive charges in bore holes, which comprises:

• a tubular loading member having a passageway in a side wall thereof for receiving an explosive charge;
• means for moving said tubular loading member into and out of a bore hole;
• means for advancing said charge within said tubular loading member into emplacement within said bore hole;
• means mounted to said advancing means for impacting said emplaced charge to initiate said charge;
• and
• means responsive to actuation of said impacting means for actuating said moving means to retract said tubular loading member and said advancing means from said bore hole during the delay period of said initiated charge.

Apparatus for loading and initiating a percussion initiatable delay type explosive charge in a bore hole which comprises:

• a longitudinally extending tubular support member positionable in alignment with and adjacent to said bore hole;
• a tubular loading member having a passageway in a side wall thereof for receiving an explosive charge, said tubular loading member being longitudinally movable within and through a forward end of said tubular support member so as to be advanced into said bore hole from within said support member;
• means for moving said tubular loading member through said forward end of said tubular support member into and out of a bore hole;
• means for advancing said charge within said tubular loading member into emplacement within said bore hole;
• means mounted to said advancing means for impacting said emplaced charge to initiate said charge;
• and
• means responsive to actuation of said impacting means for actuating said moving means to retract said tubular loading member and said advancing means from said bore hole during the delay period of said initiated charge.

Apparatus for drilling and blasting to form earth breakage product comprising:

• a support member;
• means for rotation of said support member;
• a centrally disposed drill carried by said support member for drilling a relief hole in an earth formation;
• a plurality of space-apart drilling units, each carried by said support member for forming a bore hole in said earth formation, each of said drilling units spaced from said centrally disposed drill;
• means mounted to said support member for loading and initiating delay type percussion initiatable explosive charges in said bore hole including:
• a tubular loading member having a passageway in a side wall thereof for receiving an explosive charge,
• means for moving said tubular loading member into and out of a bore hole,
• means for advancing said charge within said tubular loading member into emplacement within said bore hole,
• means mounted to said advancing means for impacting said emplaced charge to initiate said charge, and
• means responsive to actuation of said impacting means for actuating said moving means to retract said tubular loading member and said advancing means from said bore hole during the delay period of said initiated charge;
• and
• means for advancing said support member toward said earth formation for said drilling and loading and subsequent initiation of each of said explosive charges for detonation to form said breakage product.

A method for loading and initiating a delay type percussion initiatable explosive charge in an earth formation, which comprises:

• moving said delay type explosive charge into a bore hole in said earth formation;
• advancing a percussion member into contact with said charge to initiate said charge;
• and
• withdrawing said percussion member from said bore hole during the delay period of said charge.