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:
Jan. 18, 1977
Filed:
Dec. 18, 1975
Kemal Butka, New York, NY (US);
Other;
Abstract
A mechanical pencil, especially for thin leads, in which a tubular guide projects from and is guided for movement in axial direction in one end of a tubular casing. Lead is automatically advanced through the casing as a function of pressure exerted on the tubular guide during writing or drawing by successively compressing and expanding a tubular, resilient element having a conically-shaped end. During writing or drawing, the resilient element is compressed and its conically shaped end is wedged in tight engagement into a cooperating conically shaped end of an abutment member so as to clamp lead passing through the casing, thereby preventing the lead from moving inwardly during writing. When pressure is terminated, the resilient element is restored to its expanded condition, thereby freeing the lead to advance.