|국가/구분||United States(US) Patent 등록|
|미국특허분류(USC)||264/572; 264/3287; 264/500; 425/130|
|§371/§102 date||19990803 (19990803)|
|발명자 / 주소|
|출원인 / 주소|
|대리인 / 주소||
|인용정보||피인용 횟수 : 10 인용 특허 : 10|
A gas injection moulding device with a mould cavity which communicates via a valve with spill chambers. The injection moulding process is controlled by a control unit so that the valve is first kept partially open during the injection of fluent plastic material for purging the mould cavity of air and for spilling a first small amount of plastic material to the spill chambers, whereas during the subsequent injection of gas, the valve is completely opened.
1. Method of manufacturing a plastic article with a cavity enclosed in the same, comprising the following steps:injection of plastic material under pressure into a mould cavity, cooling the plastic material closest to the walls of the mould cavity, injection of gas under pressure into fluent plastic material, which is surrounded by the cooled plastic material, pressing out fluent plastic material to at least one spill chamber located outside the mould cavity and communicating with the mould cavity, by means of the injected gas to form a cavity in the pla...