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. 30, 1993
Filed:
Jul. 17, 1991
Toyoda Gosei Co., Ltd., Nishikasugai, JP;
Abstract
A mold for hollow injection molding has an inlet for admitting a fluid into the molten resin when injected to form an interior hollow in the molded product. The inlet is opened and closed by retraction and advancement of a movable pin having at least a portion to fill the inlet and close it. When the inlet is closed, while the resin is being injected, the pin has a portion which projects out of the inlet into the space where the resin is injected. When the inlet is opened, the retraction of the pin leaves a short passageway in the injected resin leading from the fluid inlet for flow thereinto of the hollow-forming fluid. Preferably, the pin is stepped with an inlet-closing large rear portion and a smaller projecting forward portion which is located in and has an annular clearance with the inlet when it is open. The pin may be detachably connected to a movable plunger, operated by fluid or spring pressure, to enable replacement by pins of different lengths, sizes, etc.