IP Library › Granted Patent US 5,456,575
Granted Patent Utility
US 5,456,575 · App. 08/242,937

Non-centric improved pumping stage for turbomolecular pumps

Inventors: John C. Helmer, Giampaolo Levi
Patented Case View Patent ↗
Granted: Oct 10, 1995 Filed: May 16, 1994
Inventors
John C. Helmer
Giampaolo Levi
Assignee (at issue)
Varian, Inc.

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 5,456,575
App. No.
08/242,937
Filed
1994-05-16
Granted
1995-10-10
Kind
A