Method and apparatus for preventing thermal damage to a preformed plug during molding of a housing therearound
US4430285A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 23, 1981 |
| Grant date | Feb 7, 1984 |
| Priority date | — |
| Expiry date | Oct 23, 2001 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16K27/067
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A rotary plug valve is formed which is of the type comprising a housing formed of a polymer and a rotary plug disposed in a through-passage of the housing. The plug is formed of a polymer and includes a bore selectively alignable with the through-passage to admit the passage of fluid. The plug valve is formed by forming the plug and attaching thereto a preformed polymeric shield by snap-fitting the shield onto the plug. The shield has an inner surface conforming to the periphery of the plug. The plug and shield assembly is positioned within a cavity of a mold. The cavity corresponds to the shape of the housing. A molten polymer is introduced into the cavity and intimately contacts the shield and forms the housing around the plug.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.