Method of making a molded plastic elbow
US7264761B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 18, 2005 |
| Grant date | Sep 4, 2007 |
| Priority date | — |
| Expiry date | Jan 20, 2026 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/139
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An improved molded plastic elbow and a related mold assembly and manufacturing method are provided, wherein the elbow defines an internal flow path having a smoothly radiused inside turn. The elbow is formed by injecting plastic material into a tubular mold cavity formed by closed mold members in cooperation with a pair of slidably retractable core units of circular cross section and having distal ends in mating, angularly set end-to-end contact to form the internal flow path having a turn formed along the length thereof. Each core unit comprises an outer core pin to form an outer portion of the flow path and including a ramped track for slide-fit mounting of an inner slide segment which forms an inner portion of the flow path and further includes a curved inside edge to form a portion of the smoothly radiused inside turn. Initial retraction of each outer core pin from the mold cavity permits relative advancement of the inner slide segment along the ramped track toward a centerline of the flow path, sufficiently for the curved inside edge of the inner slide segment to clear the radiused inside turn of the molded elbow and thereby enable interference-free linear withdrawal of the co…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.