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. 20, 2003
Filed:
Jun. 13, 2001
Toshihiro Kanematsu, Atsugi, JP;
Yasuo Yamanaka, Kawasaki, JP;
Akira Fukushima, Yokohama, JP;
Kiyotaka Sawada, Atsugi, JP;
Motoyasu Murai, Atsugi, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An apparatus for producing a plastic molded article or product for use in an optical device is a mold assembly. The mold assembly includes a pair of molds having an inner mold surface forming a cavity with a preselected volume into which a molten molding material is injected via a gate or sprue to fill the cavity and thereby form a molded product having a sink surface and at least one mirror surface after the molten molding material has cooled. The inner mold surface includes at least one transfer surface portion against which the at least one mirror surface of the molded product is formed, and at least one non-transfer surface portion against which the sink surface portion of the molded product is formed. The mold assembly also includes at least one vent hole, at least one bore in communication with the vent hole so that a preselected air pressure is applied to the molten molding material in the cavity via the bore and the vent hole, and at least one exhaust hole adjacent to, but spaced from the vent hole. Thus, only a part of the molded article or product expected to sink is surely caused to sink while, e.g., a mirror surface is surely transferred to a desired part of the molded article or product.