Molding apparatus
US5700498A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 1995 |
| Grant date | Dec 23, 1997 |
| Priority date | — |
| Expiry date | Sep 18, 2015 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2031/24
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Apparatus for blow-molding an article curved in three dimensions comprises two horizontally movable mold parts which, when in contact with each other, define a mold cavity curved in three dimensions to match the required article. An extrusion head extrudes a parison of synthetic resin material into the cavity so that it descends towards the lower end thereof. During this process, a first air flow is fed through apertures in a cover and passes through the mold cavity around the outside of the parison to ease the passage of the parison towards the lower end. In addition, a second air flow is fed through a nozzle in the extrusion head into the interior of the parison so as to help it descend and also to prevent its distortion as it moves into the mold cavity. Thereafter, closure members, which are slidable on, but movable independently of, the main mold parts, close off the upper and lower ends of the mold cavity and pinch the parison between them, their movements being controlled by respective actuators. Blow-molding then takes place in order to produce the required article. The mold parts are then separated. The article remains suspended by the closure members and can be grabbed by …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.