| 摘要 |
An apparatus for obtaining a negative pressure in chambers formed by a flat extractor plate supporting frustoconical or truncated pyramidal objects thermoformed from a sheet of synthetic material, embodying a flat extractor plate for hollow frustoconical or trucated pyramidal objects which when resting their rims on the flat surface of the extractor plate form chambers, wherein a suction unit is connected with said chambers by means of a pipe and a connecting cavity and wherein are provided a shut-off valve and an air intake(20) adjustment valve between the unit and the said valve, wherein each chamber is provided with at least one intake for atmospheric air into the chambers (17), wherein the cross-section of the intakes (20) is variable. |
