Plastic material molding apparatus
US4867665A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 9, 1988 |
| Grant date | Sep 19, 1989 |
| Priority date | — |
| Expiry date | Sep 9, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C2948/92961
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A plastic material molding apparatus, wherein when the pressure at a material inlet of a cylinder of a material holding mechanism increases as a piston in the cylinder compresses a resilient member provided in the material holding mechanism, the speed of a motor for driving a material fluidizing mechanism is reduced. A servo motor for intermittently driving a plastic material metering and delivering mechanism is controlled according to the revolution speed and a predetermined total number of revolutions of the servo motor and to the number of pulses from a pulse generator provided in the servo motor. A relief valve is interposed between a material delivery port and a delivery nozzle of the metering and delivering mechanism, the relief valve being adapted to open when the material pressure at the delivery port is higher than the relief pressure, the relief pressure being set higher than the vapor pressure according to the temperature of the material at the delivery port. When the amount of material delivered to the material holding mechanism reaches a specified volume, the fluidizing mechanism is made to continue its operation and the material contained in the material holding mecha…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.