MOULD FILLING WITH SUBSEQUENT CLOSING UNDER INTERNAL PRESSURE

Abstract

Disclosed is an apparatus for expanding and filling plastic parisons to form plastic containers with a liquid medium, with at least one transforming station which has a hollow mould, inside which the plastic parisons can be expanded into plastic containers and can be simultaneously filled by application of a liquid medium, wherein the transforming station is arranged on a carrier and wherein the transforming station has a filling device which feeds the liquid medium to the plastic parisons under pressure, wherein the transforming station has a pressure chamber to which a gas can be applied, wherein for filling of the plastic parisons the filling device can be introduced into the pressure chamber and after the filling can be removed at least partially, and wherein a closing unit can be introduced into the pressure chamber, in order to close the expanded und filled plastic containers.

Claims

1: An apparatus for expanding and filling plastic parisons to form plastic containers with a liquid medium, with at least one transforming station which has a hollow mould, inside which the plastic parisons can be expanded into plastic containers and simultaneously filled by application of the liquid medium, wherein the transforming station is arranged on a carrier and wherein the transforming station has a filling device which feeds the liquid medium to the plastic parisons under pressure, wherein the transforming station has a pressure chamber to which a gas can be applied, wherein for filling of the plastic parisons the filling device can be introduced into the pressure chamber and after the filling can be removed at least partially, and wherein a closing unit can be introduced into the pressure chamber, in order to close the expanded und filled plastic containers.

2: The apparatus according to claim 1, wherein the filling device is configured to be applied to a mouthpiece of the plastic parison in a sealing manner.

3: The apparatus according to claim 1, wherein the feed direction of the closing unit is at an angle different from 0 with respect to a longitudinal axis of the plastic containers.

4: The apparatus according to claim 1, wherein the filling device is configured to be introduced obliquely with respect to a longitudinal axis of the plastic parisons into the pressure chamber.

5: The apparatus according to claim 1, wherein the closing unit is arranged in an axis with a longitudinal axis of the plastic parison or of the plastic container and/or is movable in a straight line on the plastic container, in order to attach a container closure to a mouthpiece of the plastic container.

6: The apparatus according to claim 1, wherein the closing unit is configured to be withdrawn completely from the pressure chamber.

7: The apparatus according to claim 1, wherein the filling device is provided with a drive which is configured to move the filling device.

8: The apparatus according to claim 1, wherein the pressure chamber has a seal which is configured to seal the pressure chamber relative to the hollow mould and/or the plastic parison or the plastic container.

9: The apparatus according to claim 1, wherein the pressure chamber has a pressure regulator configured to set the pressure level in the pressure chamber.

10: A method for expanding and filling plastic parisons to form plastic containers with a liquid medium, wherein inside a hollow mould of a transforming station the plastic parisons are expanded into plastic containers and simultaneously filled by application of a liquid medium, wherein a filling device of the transforming station fills the plastic parisons under pressure with the liquid medium, and wherein a closing device closes the expanded and filled plastic containers, wherein the plastic containers are closed while they are still located in the transforming station and are under a pressure which lies above the ambient pressure.

11: The method according to claim 10, wherein after the expansion and filling, the plastic containers are not completely relieved of pressure, but until closing a pressure which lies above the ambient pressure and in particular above a saturation pressure is maintained.

12: The method according to claim 10, wherein during the expansion and filling of the plastic parisons a counter-stretch rod is moved from below against a tip of the plastic parisons.

13: The apparatus according to claim 1, wherein the filling device is configured to be introduced obliquely with respect to a longitudinal axis of the plastic parisons into the pressure chamber at an angle between 20 and 65.

14: The apparatus according to claim 2, wherein the filling device is configured to be introduced obliquely with respect to a longitudinal axis of the plastic parisons into the pressure chamber.

15: The apparatus according to claim 2, wherein the filling device is configured to be introduced obliquely with respect to a longitudinal axis of the plastic parisons into the pressure chamber at an angle between 20 and 65.

16: The method according to claim 10, wherein the plastic containers are closed while they are still located in the transforming station and under pressure from a pressure chamber.

17: The method according to claim 11, wherein during the expansion and filling of the plastic parisons a counter-stretch rod is moved from below against a tip of the plastic parisons.

Description

[0079] Further advantages and embodiments are apparent from the appended drawings.

[0080] In the drawings:

[0081] FIG. 1 shows a schematic representation of the transforming station according to the invention;

[0082] FIG. 2 shows an enlarged schematic representation of the transforming station according to the invention;

[0083] FIG. 3 shows a possible configuration of the seals of the closing unit;

[0084] FIG. 4 shows a diagram with preferred pressure profile;

[0085] FIG. 5 shows a diagram in the event of a pressure reduction in stages;

[0086] FIG. 6 shows a schematic representation of an apparatus according to the invention.

[0087] FIG. 1 shows a schematic representation of a transforming station according to the invention. It shows the hollow mould 12, in which a plastic parison 10 can be expanded into a plastic container 20 (represented by a broken line). This hollow mould 10 comprises the complete main body of the plastic parison or plastic container. The mouthpiece 10a of the plastic parison or plastic container projects out of this hollow mould. The pressure chamber 4 is located above the hollow mould 12. This comprises the mouthpiece 10a of the plastic parison or plastic container.

[0088] The filling device 6 is fitted onto the mouthpiece 10a. The filling device is obliquely with respect to the longitudinal axis L of the plastic parison or plastic container. The longitudinal axis of the plastic parison or plastic container and the longitudinal axis of the filling device E lie at an angle relative to one another.

[0089] Liquid medium from a reservoir 26 is delivered to the plastic parison by means of the filling device 6. The liquid medium is delivered by means of pressure. The pressure is generated by means of a pressure generating device 30. The filling device can be moved by means of a drive 18, in particular at least partially withdrawn from the pressure chamber 4 or introduced into it. The introduction or withdrawal movement preferably takes place in a straight line, and thus also during the movement the longitudinal axis of the plastic parison or plastic container and the longitudinal axis of the filling device E lie at an angle relative to one another. The drive 18 may for example be an electric motor.

[0090] A gas can be delivered to the pressure chamber 4 or drawn off from the pressure chamber by means of conduits 28. The delivery or discharge of the gas is undertaken by the pressure regulator 24.

[0091] There is a closer receiving opening 32 on the upper side of the pressure chamber 4. A closing unit 8 can be introduced into this opening. When the closing unit 8 is introduced, the closer receiving opening 32 is completely closed. The closing unit 8 can hold a container closure 18 by means of a holding device.

[0092] FIG. 2 shows an enlarged detail of the transforming station according to the invention, in particular the pressure chamber 4. In particular it again shows the hollow mould 12, the filling device 6, which is pressed onto the mouthpiece 10a, and the closing unit 8. It can be seen that the pressure chamber 4 is sealed downwards towards the hollow mould 12 by seals 22, towards the filling device with seals 34 and towards the closing unit with seals 36.

[0093] FIG. 3 shows a possible configuration of the closing unit 8. Here too the seals 36 can be seen. Additionally it can be seen that the closing unit 8 can be moved by means of a longitudinal guide 38 into the pressure chamber 4 or discharged therefrom. Also with regard to the longitudinal guide 38 there must be a seal 40.

[0094] In a t-p diagram FIG. 4 shows the pressure profile in the course of the method according to the invention. At the beginning of the moulding phase the pressure is increased. The pressure can be increased in stages. Then follows a holding phase, in which the pressure is kept constant over a certain time t. Then comes a pressure relief phase, in which the pressure dropsabruptly in FIG. 4. In this case, however, the pressure does not drop back to the starting level, the ambient pressure. Instead of this a certain internal pressure persists. In this case this internal pressure lies in particular above a saturation pressure of the carbonised filling material (shown by a broken line).

[0095] FIG. 5 shows that after the holding phase the pressure can also decay in stages. In this case the pressure can recede preferably likewise only up to a certain internal pressure above the saturation pressure. However, it would also be conceivable (shown by a broken line) that after decaying in stages the pressure recedes to ambient pressure,

[0096] FIG. 6 shows an apparatus according to the invention with several transforming stations. In this case the transforming stations are arranged on a movable carrier. FIG. 6 shows as an example an apparatus of the rotary machine type, in which the transforming stations are arranged on a rotatable carrier. However, it is likewise conceivable that the transforming stations are mounted on a linear carrier.

[0097] The applicant reserves the right to claim all the features disclosed in the application documents as essential to the invention in so far as they are individually or in combination novel over the prior art. Furthermore it is pointed out that in the individual drawings features were also described which may be advantageous per se. The person skilled in the art recognises immediately that a specific feature described in a drawing may also be advantageous without the incorporation of further features from this drawing. Furthermore the person skilled in the art recognises that advantages may also result from a combination of several features shown in individual drawings or in different drawings.

LIST OF REFERENCES

[0098] 1 apparatus [0099] 2 transforming station [0100] 4 pressure chamber [0101] 6 filling device [0102] 8 closing unit [0103] 10 plastic parison [0104] 10a mouthpiece of the plastic parison/plastic container [0105] 10b main body of the plastic parison/plastic container [0106] 12 hollow mould [0107] 14 carrier [0108] 16 container closure [0109] 18 drive [0110] 20 plastic container [0111] 22 seal [0112] 24 pressure regulator [0113] 26 reservoir for liquid medium [0114] 28 conduits [0115] 30 compressed air generating device [0116] 32 closer receiving opening [0117] 34 seals for filling device [0118] 36 seas for closing unit [0119] 38 longitudinal guide [0120] 40 seals for longitudinal guide [0121] L longitudinal axis of a plastic parison/plastic container [0122] E longitudinal axis of the filling device [0123] angle between the longitudinal axis of the plastic parison or plastic container and the on axis of the filling device E