Externally powered core catcher

An improvement in coring apparatus including a coring bit, outside tube and inner tube concentrically disposed within said outside tube, and including means for selectively longitudinally displacing said inner tube, said coring bit for cutting a core, said core being disposed within said inner tube, said improvement comprising:

• a slidable core catcher means for seizing said core;
• first means coupled to said slidable core catcher means for selectively longitudinally displacing said slidable core catcher means with respect to said inner tube without dependence on gravity or diametral fit of said slidable core catcher means with said core, said first means coupled to said inner tube and longitudinally displaced therewith;
• second means for releasing said slidable core catcher means from said first means after said slidable core catcher has been longitudinally displaced with respect to said inner tube by a predetermined distance;
• and
• third means for activating said slidable core catcher means to cause said core catcher means to seize said core as said slidable core catcher means is longitudinally displaced through said predetermined distance.

An improvement in a coring apparatus including a coring bit, outside tube and inner tube concentrically disposed within said outside tube, said coring bit for cutting a core, said core being disposed within said inner tube, said improvement comprising:

• a slidable core catcher;
• first means coupled to said core catcher for longitudinally displacing said slidable core catcher with respect to said inner tube;
• and
• second means for releasing said slidable core catcher from said first means after said slidable core catcher has been longitudinally displaced by a predetermined distance, wherein said first means for longitudinally displacing said slidable core catcher with respect to said inner tube comprises an outer tube ring member coupled to said outer tube and longitudinally fixed thereto and radially extending within said outer tube toward said inner tube, said inner tube being slidable within said outer tube ring member, an inner tube ring member selectively coupled to said inner tube and selectively coupled to said slidable core catcher, said inner tube ring member arranged and configured to first contact said outer tube ring member thereby selectively decoupling said inner tube ring member from said inner tube after which said slidable core catcher is longitudinally displaced with respect to said inner tube by continued contact between said inner tube ring member and said outer tube ring member, said slidable core catcher then being selectively decoupled from said inner tube ring member after a predetermined amount of longitudinal displacement of said slidable core catcher with respect to said inner tube.

An improvement in a coring apparatus including a coring bit, outside tube and inner tube concentrically disposed within said outside tube, said coring bit for cutting a core, said core being disposed within said inner tube, said improvement comprising:

• a slidable core catcher;
• first means coupled to said core catcher for longitudinally displacing said slidable core catcher with respect to said inner tube;
• second means for releasing said slidable core catcher from said first means after said slidable core catcher has been longitudinally displaced by a predetermined distance;
• and
• third means for operating said slidable core catcher to cause said core catcher to seize said core as said slidable core catcher is longitudinally displaced through said predetermined distance,
• wherein said third means comprises an inner conical surface formed within said inner tube, said slidable core catcher being disposed within said inner tube and displaced by said first means downwardly within said inner tube across said conical surface so that said conical surface compresses said core catcher and causes said core catcher to grip said core, said first means lifting said inner tube with respect to said outer tube and said slidable core catcher being selectively longitudinally fixed with respect to said outer tube as said inner tube is lifted by said first means.