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:
May. 15, 1984
Filed:
Jul. 19, 1982
Oki Densen Kabushiki Kaisha, Kanagawa, JP;
Abstract
A pressure-sensitive, conductive elastic sheet for use in a graphics digitizing tablet through which various letters or figures can be detected, the characteristics of which are such that the contact pressure is almost constant irrespective of contact area or increases with increasing contact area. The pressure-sensitive sheet according to the present invention comprises a silicon rubber in which a number of coarse, ferromagnetic, conductive metal particles with a diameter of 30 to 150 micron are mixed with a number of fine, ferromagnetic, conductive metal particles with a diameter of 10 micron or less or 50 micron or less at a predetermined proportion in such a manner that the coarse particles are aligned vertically through the interior thereof and the fine particles are dispersed near at least one surface thereof. To properly align the particles, the sheet is allowed to set within a uniform magnetic field.