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:
Mar. 04, 1986
Filed:
Jan. 12, 1983
Michael Shepherd, Carmel, IN (US);
Wallace Murray Corporation, New York, NY (US);
Abstract
An electric motor construction particularly for subway train electric motors which utilize fan induced air cooling to cool the motor windings. The invention exhibits utility in saving power to drive the fan. The fan is coupled to the motor armature by a fluid coupling. The fluid coupling is so constructed that at relatively high temperatures the torque delivered to the fan by the motor armature does not increase proportionally or correspondingly as at relatively low rotor speeds. On one embodiment, a fluid coupling utilizing variation of shear liquid viscosity with both temperature and shear rate is employed. In a second embodiment, the amount of fluid in the fluid coupling is varied with variations in temperature.