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:
Jul. 18, 1978
Filed:
Mar. 01, 1977
Eugene K Sokolowski, Chicago, IL (US);
Teletype Corporation, Skokie, IL (US);
Abstract
Paper is carried on an apertured platen and is rotated past a slowly moving printing head so as to scan in a raster fashion from top to bottom and from left to right over the surface of the paper. The paper is held to the platen drum by a vacuum that is applied to the inside of the platen. A valve is located at the entrance of the vacuum system of the platen in order to rapidly dissipate the vacuum so as to release or remove the paper from the still rapidly rotating platen. To facilitate inserting and releasing paper, a shroud system is placed very close to the periphery of the drum and guides the paper during insertion to close proximity with the vacuum. An exit door is provided in the shroud at a convenient location to permit the paper to exit from the drum once the vacuum has been dissipated. The size of the drum is made such that its circumference is slightly less than the length of the paper so as to provide overlap of the top and bottom edges of the paper. A light beam is directed tangential to the platen and is blocked once per revolution by the projection of flap of the overlapping edge of the paper. A photocell is placed opposite the light source and senses the temporary blockage of the light beam by the overlapping edge of the paper as the platen rotates.