Check valve for a fluid-assisted plastic injection molding apparatus
US5149546A · kind A · utility
10Cited by
5References
24Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 1, 1991 |
| Grant date | Sep 22, 1992 |
| Priority date | — |
| Expiry date | Jul 1, 2011 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C45/1735
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A check valve is provided that is especially useful in gas-assisted injection molding wherein pressurized gas is injected into molten plastic material. A tapered or cone-shaped valve member which seats into a correspondingly tapered or cone-shaped valve chamber provides the mechanism by which the valve seals against reverse flow. Any plastic material entering the gas passageway would contact the base end of the tapered or cone-shaped valve member and not any sealing surfaces. By minimizing contact with the sealing surfaces, the useful lifetime of the check valve is significantly increased.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.