Differenze tra le versioni di "File:SheafferPressureBar.jpg"

Informazioni

Schema di un caricamento a levetta e relativo meccanismo della barra di pressione della Sheaffer. Estratto dalla prima pagina del brevetto originale (nº US-1852094). Ritoccato dall'autore per una maggiore nitidezza.

Schema of a Sheaffer lever filler system, with its peculiar pressure bar mechanism. Excerpt from original patent (nº US-1852094) first page. Retouched by the author for a better sharpness.

Licenza

The text and illustrations of US patents are in the public domain unless the patent text contains a specific notice that portions are copyrighted.[1][2] [3] The original patent contains no such notice, so its contents are in the public domain. Note This only applies to images published before March 1, 1989. Patents published after that date are most likely copyrighted, unless PD for another reason, like being uneligible for copyright.

I, the copyright holder of this work, hereby grant the permission to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.