The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 16, 1994
Filed:
Dec. 18, 1992
Applicant:
Inventors:
Daniel Egan, St. Paul, MN (US);
Jerry Alexander, St. Paul Park, MN (US);
James T McKinney, Stillwater, MN (US);
John F Runyon, St. Paul, MN (US);
Assignee:
Minnesota Mining and Manufacturing Company, St Paul, MN (US);
Primary Examiner:
Int. Cl.
CPC ...
G01L / ;
U.S. Cl.
CPC ...
738656 ;
Abstract
A drive roller torque reference cartridge for calibrating a drive force tester. The reference cartridge uses a magnetic hysteresis brake assembly to controllably resist the rotation of the cartridge drive roller. The magnetic hysteresis brake assembly includes a cylindrical permanent magnet within the drive roller and a coaxial remanently magnetizable sleeve surrounding the drive roller. The drag created by the reference cartridge is substantially independent of the temperature and rotational speed of the drive roller.