IP Library › Granted Patent US 4,243,727
Granted Patent Utility
US 4,243,727 · App. 05/790,795

Surface smoothed tool joint hardfacing

Inventors: Allen E. Wisler, Leo D. Lane
Patented Case View Patent ↗
Granted: Jan 6, 1981 Filed: Apr 25, 1977
Inventors
Allen E. Wisler
Leo D. Lane
Assignee (at issue)
Hughes Tool Company LLC

This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.

Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 4,243,727
App. No.
05/790,795
Filed
1977-04-25
Granted
1981-01-06
Kind
A