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. 27, 1979
Filed:
Oct. 14, 1975
John M Vandling, Pleasantville, NY (US);
Exxon Research & Engineering Co., Florham Park, NJ (US);
Abstract
In a facsimile system, rotation of a transmitter drum carrying a document is synchronized with the rotation of a receiver drum carrying a copy medium. Synchronization of the rotating transmitter drum and the rotating receiver drum is assured by driving the transmitter drum from an AC power line and locking the receiver drum to the AC power line frequency once synchronization of the transmitter drum and the receiver drum have been achieved. In order to achieve initial synchronization, the drive for the receiver drum is initially locked to a source of controlled frequency until a predetermined angular position of the receiver drum relative to a predetermined angular position of the transmitter drum is attained. The receiver motor which is of the DC type is controlled in angular frequency after initial synchronization by generating a signal having a frequency phase locked to the AC power line frequency.