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:
Mar. 02, 2004
Filed:
Mar. 13, 2000
Hiroo Nomura, Fukushima-ken, JP;
Yuichi Yasuda, Fukushima-ken, JP;
Yoshihisa Endo, Fukushima-ken, JP;
Alps Electronic Co., Ltd., Tokyo, JP;
Abstract
A keyboard unit capable of making large the stroke of a key top and a sure click touch. In one aspect of the invention, the keyboard unit of the present invention comprises an elastic material such as a domed reversible return spring. In another aspect, a predetermined space is formed between a piezoelectric element and the base plate. The piezoelectric elements may extend underneath two support bodies from a first support body to a second support body. Each membrane switch and the return spring is depressed and reversed by a stem, wherein each of the piezoelectric elements is driven through the contact point of the respective membrane switch. The resulting driving force is transmitted to the respective key top through the stem. The stem is then elastically deformed and contracted by the inertia force pressing the key top to produce the stroke of the key top.