Bore hole tool with magnetic blade retention

Abstract

A bore hole tool which uses magnetic means to retain the tool in a closed or collapsed position when in a non-operating mode while able to release from the magnetic retention to an open or enlarged position when said tool is in an operating mode when rotation is applied or fluid is pumped through said tool.

I claim: 
     
         1 . A bore hole tool apparatus blade retention system which uses magnetic means in the body to keep moveable blades in a closed position when not in an operating mode, whereby said magnetic means are of a predetermined strength to retain said blades in a closed position in a vertical, angled or horizontal well bore, and whereby said magnetic means are of a predetermined limited strength to allow the blades to open to an operating position when rotation of the drill string is actuated or fluid is pumped through the drill string and said tool blades. 
     
     
         2 . In an apparatus according to  claim 1  wherein said magnetic means are positioned adjacent to the distal end of the blades. 
     
     
         3 . In an apparatus according to  claim 2  wherein said magnetic means are retained in the body by hardened fluid encasement material. 
     
     
         4 . In an apparatus according to  claim 2  wherein said magnetic means are retained in the body by pin or bolt means. 
     
     
         5 . A bore hole tool blade retention system which uses magnetic means in the blades to keep moveable blades in a closed position when not in an operating mode, whereby said magnetic means are of a predetermined strength to retain said blades in a closed position in a vertical, angled or horizontal well bore, and whereby said magnetic means are of a predetermined limited strength to allow the blades to open to an operating position when rotation of the drill string is actuated or fluid is pumped through the drill string and said blades. 
     
     
         6 . In an apparatus according to  claim 5  wherein said magnetic means are positioned at the distal end of the blades. 
     
     
         7 . In an apparatus according to  claim 6  wherein said magnetic means are retained in the blades by hardened fluid encasement material. 
     
     
         8 . In an apparatus according to  claim 6  wherein said magnetic means are retained in the blades by pin or bolt means. 
     
     
         9 . A bore hole tool apparatus blade retention system which uses magnetic means in the body to keep moveable blades in a closed position when not in an operating mode, whereby said magnetic means are of a predetermined strength to retain said blades in a closed position in a vertical, angled or horizontal well bore, and whereby said magnetic means are of a predetermined limited strength to allow the blades to open to an operating position when rotation of the drill string is actuated or fluid is pumped through the drill string and said tool blades, wherein said magnetic means are positioned adjacent to the distal end of the blades and retained in the body by hardened fluid encasement material.