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. 19, 1981
Filed:
Oct. 26, 1978
W S Henrion, Houston, TX (US);
Raymond K Erickson, Missouri City, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A solid state keyboard comprised of a base module, a plurality of key members each having a plunger member comprised of a uniform mixture of a magnetic material such as barium ferrite and a binder such as nylon, and a respective plurality of improved Hall Effect Generators, provides a significant improvement in performance and cost effectiveness. Actuation of a key member moves its plunger member, which has a preselected magnetic field, relative to an improved Hall Effect Generator, in which offset voltage has been substantially eliminated. This movement exposes the generator to a change in the direction of the magnetic field, thus causing a corresponding change in the output voltage of the generator from a first predetermined voltage to a second predetermined voltage. A unique tripolar magnetic arrangement on the plunger member provides positive switching and better control of switching points.