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:
Dec. 22, 1998
Filed:
Dec. 18, 1996
Victor Company of Japan, Ltd., Yokohama, JP;
Abstract
Improved disc metal mold provides an improved disc without a ring groove thereon. The improved disc metal mold has a fixed metal mold section and a movable metal mold section for forming a cavity therebetween. One of the fixed and movable metal molds has a stamper having an information signal surface on which an information signal is formed in a form of pits, wherein a fused resin is injected into the cavity to form a disc substrate having a center through hole at the center thereof. The disc metal mold includes the stamper having an center hole at a center thereof for retaining the stamper itself and a retainer for retaining the stamper to engage with the center hole of the stamper. The retainer has a slightly larger diameter at a top surface thereof than a diameter of the center hole of the stamper so that the top surface of the retainer is approximately flush with the information signal surface of the stamper by causing the top end thereof to engage with the center hole of the stamper. Thus, it is possible to provide a recorded disc having a seamless flush information surface without ring groove.