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:
Dec. 22, 1992
Filed:
May. 16, 1990
Sadao Unuma, Aichi, JP;
Tokai Kogyo Kabushiki Kaisha, Oobu, JP;
Abstract
A paper feeding tractor in which perforated paper is fed by a pin carrying feed belt includes a feed belt driving sprocket which is housed between a pair of side frames. Two side faces of an inner circumferential portion of the sprocket body, except an outer circumferential portion formed with teeth, are formed with round fitting protuberances concentric with an axial hole therein such that the inner circumferential portion of the sprocket body is thinner than the outer circumferential portion. Thus, contact between the sprocket and the drive shaft is reduced to a relatively small sliding resistance. Paper can be moved in the axial direction of the drive shaft by a small force. During paper feed, any phase difference in rotation between the drive shaft and the sprocket can be eliminated. Alternatively, the feeding sprocket and a belt reception rotary member are housed within an auxiliary frame structure which is fit within and longitudinally slidable with respect to the main frame structure.