Patent assignee · US · COMPANY

Longyear™, Inc.

19Patents
1Active
19Granted
31Portfolio score

Filing activity: Mar 8, 1974 → Apr 27, 2010 · 1 expiring within 5 years

Most-cited patents

PatentTitleAreaCited byStatus
US4823890A Reverse circulation bit apparatus Emerging Cross-Sectional Technologies 165 Expired
US4281722A Retractable bit system Fixed Constructions 76 Expired
US4834198A Positive latch wire line core barrel apparatus Fixed Constructions 54 Expired
US5267620A Drilling latch apparatus Fixed Constructions 53 Expired
US4800969A Fast descent core barrel apparatus Fixed Constructions 50 Expired
US5325930A Overcenter toggle latch apparatus Fixed Constructions 46 Expired
US3930679A Dry hole wire core barrel apparatus Fixed Constructions 19 Expired
US4266444A High-low speed rotary drive mechanism Emerging Cross-Sectional Technologies 18 Expired
US4281725A Knuckle joint spearhead core drilling apparatus Fixed Constructions 14 Expired
US5040438A Powered wrench apparatus Fixed Constructions 10 Expired
US4375212A Concrete sawing machine propulsion control apparatus Performing Operations; Transporting 9 Expired
US3952817A Basket type core retainer Fixed Constructions 8 Expired
US4309922A Rod break-out and make-up tool Fixed Constructions 7 Expired
US5183366A Rod handler apparatus Fixed Constructions 7 Expired
US5404959A Drill rig safety shutdown device Mechanical Engineering; Lighting; Heating 5 Expired
US4297771A Pivoting foot clamp and mounting frame Fixed Constructions 2 Expired
US5105687A Built-in rack apparatus Emerging Cross-Sectional Technologies 2 Expired
US5031708A Cockable corebreaker apparatus Fixed Constructions 1 Expired
US8347984B2 Variable force/variable frequency sonic drill head Emerging Cross-Sectional Technologies 0 Active

Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.