Method and apparatus for molding hollow, slender workpieces
US4422995A · kind A · utility
30Cited by
4References
20Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 7, 1981 |
| Grant date | Dec 27, 1983 |
| Priority date | — |
| Expiry date | Dec 7, 2001 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29K2105/253
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
There is provided a method for injection-molding an elongate hollow workpiece about a central core. A first quantity of plastic is injected into a first mold cavity through which part of the core extends, to form a spacer element around the core. After the spacer element has hardened, the core and spacer element are transferred to a second mold cavity in which the spacer element holds the core separated from the walls, thereby supporting it against lateral movement. Then, a second quantity of plastic is injected into the second mold cavity to complete the workpiece.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.