Apparatus for producing disc records with a molded-in center hole
US4402660A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 15, 1982 |
| Grant date | Sep 6, 1983 |
| Priority date | — |
| Expiry date | Jul 15, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S425/81
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An apparatus for molding information discs includes a pair of mold plates, at least one of which is movable toward and away from the other, and adapted to form a mold cavity therebetween, a center hole forming pin slidably mounted in one of the mold plates and a center plate in the other mold plate in alignment with the center hole forming pin. The center hole forming pin has a recess in its end which faces the center plate and a plurality of passages extending substantially radially therethrough from the recess to the outer surface thereof. The passages allow the flow of mold material therethrough as the center hole forming pin is moved through the mold material in the forming of the center hole to reduce the force necessary to move the pin through the mold material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.