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:
Nov. 22, 1977
Filed:
Jan. 08, 1976
Donald J Brown, Naperville, IL (US);
Knox Manufacturing Co., Wood Dale, IL (US);
Abstract
A brake mechanism for an electric motor used to drive a projection screen apparatus. The brake mechanism includes a first brake surface fixed to an exterior brake support about an end of the motor shaft projecting from the housing, a second brake surface adjustable on the shaft end and confronting the first brake surface, and a spring for normally urging the brake surfaces into engagement to prevent rotation of the shaft, and brake surfaces being urged apart and the action of the spring counteracted when the motor is operated as the rotor of the motor, which is carried by the shaft, aligns itself with the magnetic field generated by the stator of the motor.