Apparatus for blow molding aseptic containers
View Patent ↗An apparatus and method for blow molding and sealing an aseptic container. A pair of mold halves, including inner surfaces that when closed define a mold cavity, clamp about an extruded parison. The parison is inflated by high pressure blow air into conformity with the shape of the mold cavity. An evacuation device applies a force to an exterior portion of the blow molded container causing the portion to deform or flex inwardly, thereby reducing the internal volume and evacuating air from the blow molded container. A sealing tool thereafter causes the blow molded container to be sealed while the container is in the reduced volume condition. Upon removal from the mold assembly and cooling, the container returns to the desired shape.
1. An apparatus for blow molding sealed aseptic containers, said apparatus comprising:
a pair of mating mold halves including inner surfaces that when closed define a mold cavity;
a first source of pressurized air connected to provide blow air to an interior of a parison located within the mold cavity so that supply of blow air to the interior of a hot resin parison captured within the cavity is effective to expand the parison to form a blow molded container conforming to the shape of the mold cavity;
an evacuation device for applying force to the exterior of the blow molded container while the temperature thereof is above ambient temperature to deform the blow molded container to reduce the internal volume thereof and force a portion of pressurized air to be evacuated from the interior of the blow molded container, the amount of reduction of interior volume of the container effective to produce a sealed container that, at ambient temperature, that has the interior volume and shape defined by the mold cavity; and
a sealing tool being movable between a first position and a second position, the sealing tool being moveable into the second position while the volume of the blow molded container is reduced by the evacuation device thereby sealing the blow molded container with the reduced internal volute to retain residual blow air therein.
2. The apparatus of claim 1 wherein the evacuation device further comprises a plurality of air passages in fluid communication with the mold cavity, a second source of pressurized air coupled to the air passages adapted to deliver pressurized air to the mold cavity between the inner surfaces and the blow molded container therein.
3. The apparatus of claim 2 wherein the second source of pressurized air is not a source of sterile pressurized air.
4. The apparatus of claim 2 wherein the first source of pressurized air is a source of sterile pressurized air.
5. The apparatus of claim 1 wherein the first source of pressurized air is a source of sterile pressurized air.
6. The apparatus of claim 1 wherein the evacuation device comprises at least one moveable slide for deforming a blow molded container when the slide is in an extended position, the device further including an actuator coupled to move the slide between a retracted position and an extended position.
7. The apparatus of claim 6 wherein the slide is mounted within one of the mold halves and has a distal end with a surface contoured to match the inner surface of the mold cavity.
8. The apparatus of claim 7 wherein, in the retracted position, the distal end of the slide is flush with the inner surfaces of the mold cavity and in the extended position the slide is extended into the mold cavity to a position deforming the blow molded container therein.
9. The apparatus of claim 1 wherein the evacuation device comprises at lease one inflatable membrane for deforming a blow molded container when the inflatable membrane is inflated and a second source of pressurized air coupled to the inflatable membrane to deliver pressurized air to the inflatable membrane.
10. The apparatus of claim 9 wherein when the inflatable membrane is not inflated the inflatable membrane is flush with surfaces contacting the blow molded container and when the inflatable membrane is inflated by pressurized air from the second source, the membrane extends so as to deform the blow molded container.
11. The apparatus of claim 1 wherein the evacuation device is part of an evacuation station separate from a molding station.
12. The apparatus of claim 11 wherein the evacuation device includes evacuation tooling having cavity surfaces defining a cavity configured to receive the blow molded container therein.
13. The apparatus of claim 12 wherein at least one of the cavity surfaces include a portion projecting therefrom into the cavity, the portion being of a size to cause deformation of the blow molded container when the evacuation tooling is closed about the blow molded container.
14. The apparatus of claim 1 wherein the evacuation device is located in a position on at least one of the mold halves such that the device defines a surface corresponding to at least a portion of a side wall of the container defined by the mold cavity.