ALEXANDRIA, Va., March 19 -- United States Patent no. 12,252,947, issued on March 18.
"Adjustable hydraulic jarring device" was invented by Robert W. Evans (Montgomery, Texas).
According to the abstract* released by the U.S. Patent & Trademark Office: "A jarring tool includes a spring and a hydraulic piston cylinder arrangement for controlling the release of a mandrel to initiate a jarring force. The tool includes an adjustment mechanism for adjusting the minimum amount of an upward pulling force required to release the mandrel. The adjustment mechanism includes an axially adjustable trigger sleeve that cooperates with a dog clutch surrounding the mandrel."
The patent was filed on July 18, 2023, under Application No. 18/223,259.
*For fu...