| 摘要 |
Apparatus for blow moulding hollow plastic bodies from plastic preforms, or parisons, which is adapted to detect bursts occurring in plastic bottles. To this purpose, the apparatus itself comprises a differential pressure transducer arrangement ( 10, 11 ), a low-pressure gas supply source ( 103 ) along with a related first supply channel ( 101 ), a high-pressure gas supply source along with a related second supply channel ( 105 ). The differential pressure transducer arrangement is made up by one or more tubes ( 3, 4 ) arranged crosswise in the second supply channel; these tubes contain respective separate chambers opening ( 5, 6 ) into the interior of said second supply channel (Pitot tubes). Two sensors ( 7, 8 ) adapted to detect respective pressures are connected in a distinct manner to said respective chambers. Any possible pressure variation at pre-determined moments during the blow-moulding cycle is processed and compared, and the result is an indication of whether a serious irregularity, such as a burst or a silent gas leakage, took place during the blow-moulding process of a given bottle.
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