Average Co-Inventor Count = 1.39
ph-index = 21
The patent ph-index is calculated by counting the number of publications for which an author has been cited by other authors at least that same number of times.
Company Filing History:
1. Christensen, Inc. (18 from 48 patents)
2. Baker Hughes Corporation (7 from 5,728 patents)
3. Norton Christensen, Inc. (5 from 37 patents)
4. Eastman Christensen Company (2 from 38 patents)
5. Christensen Diamond Products Company (2 from 3 patents)
6. Norton Company (1 from 425 patents)
35 patents:
1. 5934383 - Steering device for steerable drilling tool
2. 5156222 - Directional drilling tool apparatus and method
3. 5109924 - One trip window cutting tool method and apparatus
4. 5052502 - Apparatus for directional coring
5. 5038873 - Drilling tool with retractable pilot drilling unit
6. 5029653 - Method for directional coring
7. 4969528 - Method and apparatus for continuous pilot hole coring
8. 4905778 - Device for producing pressure pulses in an oil well fluid medium
9. 4873522 - Method for transmitting downhole data in a reduced time
10. 4732225 - Deep-borehole drilling device with magnetic coupling
11. 4641289 - Process and device for transmitting information over a distance
12. 4614232 - Device for delivering flowable material
13. 4610307 - Method and apparatus for selectively straight or directional drilling in
14. 4553614 - Compensation device for insertion in a drill string for deep-well
15. 4537097 - Method and apparatus for manufacturing cutting elements particularly for