IP Library › Granted Patent US 4,919,348
Granted Patent Utility
US 4,919,348 · App. 07/418,857

Dust seal for gyratory rock crushers

Inventors: Louis W. Johnson, Bruce G. Johnson
Patented Case View Patent ↗
Granted: Apr 24, 1990 Filed: Oct 10, 1989
Inventors
Louis W. Johnson
Bruce G. Johnson

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 4,919,348
App. No.
07/418,857
Filed
1989-10-10
Granted
1990-04-24
Kind
A