Counter-rotating earth drill

• US 3,181,631 A
• Filed: 08/24/1962
• Issued: 05/04/1965
• Est. Priority Date: 08/24/1962
• Status: Expired due to Term

• Current Assignee: Irvin P. Nielsen
• Original Assignee: Irvin P. Nielsen
• Inventors: Nielsen, Irvin P.
• Application Number:
  US04/219,268
• Time in Patent Office: 984 Days
• US Class Current: 175/96
• CPC Class Codes: E21B 4/04 Electric drives E21B4/12 takes precedence
• CPC Class Codes: E21B 4/16 Plural down-hole drives, e.g. for combined percussion and rotary drilling E21B4/10 takes precedence; Drives for multi-bit drilling units

Claims

1. AN EARTH DRILL COMPRISING:

A HOLLOW HOUSING HAVING AN UPPER AND A LOWER END AND ADAPTED TO BE SUSPENDED AT ITS UPPER END TO A FLEXIBLE CABLE;

AN ELONGATED HOLLOW SLEEVE HAVING AB UPPER END WHICH IS ROTATABLY MOUNTED WITHIN SAID HOUSING AND A LOWER END WHICH PROJECTS BEYOND THE LOWER END OF SAID HOUSING;

AN ELONGATED STEM DISPOSED WITHIN SAID HOLLOW SLEEVE;

SAID STEM HAVING AN UPPER END ROTATABLY MOUNTED WITHIN SAID HOUSING AND A LOWER END WHICH PROJECTS BEYOND THE LOWER END OF SAID HOUSING;

AN INNER BIT MEMBER ATTACHED TO THE LOWER END OF SAID STEM;

AN OUTER BIT MEMBER ATTACHED TO THE LOWER END OF SAID SLEEVE AND SURROUNDING SAID INNER BIT MEMBER;

SAID INNER BIT MEMBER PROJECTING BELOW SAID OUTER BIT MEMBER;

A FIRST ELECTRICALLY OPERABLE DRIVE MEANS DISPOSED WITHIN SAID HOUSING AND ATTACHED TO SAID SLEEVE;

A SECOND ELECTRICALLY OPERABLE DRIVE MEANS DISPOSED WITHIN SAID HOUSING AND ATTACHED TO SAID STEM;

SAID FIRST AND SECOND DRIVE MEANS BEING OPERABLE TO DRIVE SAID SLEEVE AND STEM IN OPPOSITE DIRECTIONS AND HENCE TO SET SAID INNER AND OUTER BIT MEMBERS INTO COUNTERROTATION TO PRODUCE DRILLING OF THE EARTH;

SAID INNER AND OUTER BIT MEMBERS PRODUCING RESPECTIVELY A FIRST AND A SECOND TORQUE LOAD DUE TO ROTATION;

AND CONTROL MEANS CONNECTED SAID ELECTRICALLY OPERABLE DRIVE MEANS TO VARY THE VOLTAGE IMPARTED TO THE RESPECTIVE DRIVE MEANS TO VARY THE SPEED THEREOF TO BRING SAID FIRST AND SECOND TORQUE LOADS INTO BALANCE DURING DRILLING TO PREVENT ANY ROTATIONAL MOVEMENT OF SAID HOUSING.