Method of delivering a liquid volume and associated apparatus

Abstract

An apparatus and method of delivering a predetermined volume of a liquid product, defined as the liquid end product, formed by addition of a first and second liquid product, into a thermoplastic container formed from a heated preform positioned in a mold and having an opening opposite an injection head. Prior to injecting the second liquid product into the preform causing expansion of the container, the preform is at least partially, filled with the first liquid product.

Claims

1. A method of delivering a predetermined volume of a liquid end product into a thermoplastic container, the method comprising the steps of: forming the liquid end product by addition of a first liquid product and second liquid product; forming a thermoplastic container from a heated preform positioned in a mold and having an opening opposite an injection head; injecting the second liquid product into the preform and causing expansion of the container; and introducing the first liquid into the preform before injecting of the second liquid product, all of the first liquid being introduced into the preform before expanding of the preform in the mold cavity.

2. The method of delivering according to claim 1, wherein the preform is filled with the first liquid product prior to the step of heating the preform.

3. The method of delivering according to claim 1, wherein the preform is filled with the first liquid product at the time the preform is being heated.

4. The method of delivering according to claim 1, wherein the preform is filled with the first liquid product during transferring of the heated preform into the mold.

5. The method of delivering according to claim 1, wherein the preform is filled with the first liquid product just before the step of injecting the second liquid product and while the heated preform is disposed in the mold.

6. The method of delivering according to claim 1, wherein the first liquid product is at least a component of the liquid end product.

7. The method of delivering according to claim 1, wherein the first liquid product is similar to the second liquid product.

8. The method of delivering according to claim 1, wherein the first liquid product is similar to the liquid end product.

9. The method of delivering according to claim 1, wherein the first liquid product filled in the preform has a temperature between 10 C. and 100 C.

10. A method of delivering a predetermined volume of a liquid end product into a thermoplastic container, the method comprising the steps of: heating a preform; transferring the preform into a mold; at least partially filling the preform with a first liquid product, all of the first liquid product being filled into the preform without causing expansion of the preform; axially stretching the preform; injecting a second liquid product into the preform causing expansion of the preform and forming of the thermoplastic container; forming the liquid end product by addition of the first liquid product and the second liquid product; and wherein the step of at least partially filling the preform with the first liquid product is performed prior to the injecting of the second liquid product.

11. The method of claim 10, wherein the preform is at least partially filled with the first liquid product prior to the step of heating the preform.

12. The method of claim 10, wherein the preform is at least partially filled with the first liquid product while the preform is being heated.

13. The method of claim 10, wherein the preform is filled with the first liquid product during the step of transferring the preform into the mold.

14. The method of claim 10, wherein the preform is filled with the first liquid product just before the step of injecting the second liquid product and while the preform is disposed in the mold.

15. The method of claim 10, wherein the first liquid product is a component of the liquid end product.

16. The method of claim 10, wherein the first liquid product and the second liquid product are the same.

17. The method of claim 10, wherein the first liquid product is similar to the liquid end product.

18. The method of claim 10, wherein the first liquid product has a temperature between 10 C. and 100 C. during the step of at least partially filling the preform with the first liquid product.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is further described with reference to the following examples. It will be appreciated that the invention as claimed is not intended to be limited in any way by these examples.

(2) Embodiments of the present invention will now be described, by way of examples, with reference to the accompanying figures in which:

(3) FIG. 1 is a schematic view of an apparatus for simultaneously blowing and filing containers according to a first embodiment of the invention;

(4) FIG. 2 a schematic view of an apparatus for simultaneously blowing and filing containers according to a second embodiment of the invention.

DETAILED DESCRIPTION

(5) As used in the following description, the words comprises, comprising, and similar words, are not to be interpreted in an exclusive or exhaustive sense. In other words, they are intended to mean including, but not limited to.

(6) Any reference to prior art documents in this specification is not to be considered as an admission that such prior art is widely known or forms part of the common general knowledge in the field.

(7) FIG. 1 schematically represents an apparatus 1 in which is implemented a method for delivering a predetermined volume of a liquid product in a container that has been obtained from a preform through a simultaneous blowing and filling process, according to the present invention.

(8) The liquid in the final container, also defined as liquid end product, is for example, water, flavored water, carbonated liquid products, etc. . . . .

(9) The liquid end product is formed by the addition of a first and second liquid product. The second liquid product is the liquid product to be injected into the preform during the liquid injection step of the one step forming and filling process and the first liquid product is a liquid product that, according to the invention, is introduced in the preform prior to the liquid injection step.

(10) The preform which is used for the liquid injection blow molding of the container is first manufactured through a molding process and then heated before being positioned within a mold, as disclosed in Applicant's patent EP 1 529 620 B1.

(11) The preform usually assumes the shape of a cylindrical tube closed at its bottom end and open at its opposite end.

(12) The preform may be made of thermoplastic polymer, for example, polyethylene or terephthalate (PET)

(13) As presented in FIG. 1, the apparatus 1 comprises a blowing mold 2 defining a cavity 4 for enclosing a preform 3, a liquid injection circuit 5 and injection means 6 for injecting a liquid into the preform 3 to simultaneously form and fill a container (not represented).

(14) Mold 2 is for example a two-part mold of which the two parts or side halves define an inner cavity 4 when assembled together. For ease of representation, only a half 2a of the mold 2 is represented in FIG. 1.

(15) When the preform 3 is to be positioned in the mold 2, firstly, the two side halves are spaced apart from each other under the action of moving means (not represented in the drawing) for inserting a preform 3 there between.

(16) Next the two side halves are moved back toward each other so as to come into contact along a joint plane.

(17) The preform 3 is inserted into cavity 4 before the beginning of a blowing and filling step according to the invention.

(18) Once the preform 3 has been positioned within mold 2 only the open end of the preform is visible from above the mold 2.

(19) The shape of the cavity corresponds to the shape of the achieved container and it will be wholly occupied by the formed container at the end of the blowing and filling method.

(20) It is to be noted that mold 2 may alternatively be composed of more than two parts depending on the manufacturing process.

(21) For instance, a third part (base or bottom part) may be added at the bottom of the mold so as to define at least a part of the inner cavity bottom.

(22) The liquid injection circuit 5 (only part of it is represented) providing the liquid to the injection means 6.

(23) The injection means 6 comprise an injection head 6a which comes into a sealing contact (for liquid tightness purpose) with mold 2 and preform 3 and inject liquid into the preform 3 through an injection nozzle 7.

(24) Apparatus 1 also comprises stretching means 8 for stretching preform 3 when enclosed within mold 2 prior to or time-shifted with the liquid injection step.

(25) Stretching means 8 comprise a stretch rod 9 which is in a sliding connection with the injection nozzle 7. In FIG. 1 stretch rod 9 is in a retracted position before being used.

(26) According to the invention, prior to injecting the second liquid product in the preform, the preform is at least partially filled with a first liquid.

(27) Therefore, the apparatus further comprises preform's filling means 10 in order to fill, at least partially, the preform with the first liquid.

(28) The preform's filling means 10 comprise a filler 11 and associated liquid filling circuits (not represented).

(29) Filler 11 is a filler used in the bottling technology and well-known to the skilled person. It will not be described nor presented in details. Only a schematic representation is proposed.

(30) In the present embodiment, the preform 3 is filled with the first liquid prior to being positioned in the mold.

(31) Preferably the preform is filled before heating the preform.

(32) In a typical blow molding process, the preform is first pre-heated, generally by use of ovens, radiant heaters or any equivalent device. The temperature to which the preform is heated is one above the vitreous transition point of the material. This renders the preform soft and pliable, and thus capable of flowing into the recesses of the mold. The working temperature of a blow molding process thus ranges from 75 C. to 135 C., depending on the properties of the material used.

(33) In FIG. 1, the heating means 13 are using infra-red lamps 14 positioned along the length of the preform 3.

(34) The proposed embodiment allows to heat the preform and first liquid at the same time and to homogenize the temperature of the whole.

(35) Hence, the process presents the following steps:

(36) Step A: The preform 3 is filled with the first liquid;

(37) Step B: The preform 3 filled with the first liquid is heated in order to have the polymer approaching its vitreous temperature;

(38) Step C: The preform 3 filled with the first liquid is transferred into the cavity 4 of mold 2; and

(39) Step D: The liquid injection step takes place and the preform 3 is blow molded using the second liquid product.

(40) Therefore, during step D, the second liquid product used as injection fluid mixes with the first liquid initially in the preform.

(41) In order to have an effective mixing of the second liquid product with the first liquid, the first liquid is preferably similar to the second liquid product. In this case, the mixing is complete. For example, the second liquid product and the first liquid are both water.

(42) According to another feature, the first liquid is at least a component of the liquid end product. For example the first liquid could be a flavor concentrate, the second liquid product, water and the resulting liquid end product is flavored water.

(43) In addition to the previous characteristics, the first liquid has anti-oxidation properties to contribute to avoid oxidation of the liquid end product.

(44) Furthermore, according to the process which is implemented, it is interesting to choose the temperature of the first liquid so as to avoid disrupting the process by, for example, cooling down the preform whereas it should be kept at a temperature around the vitreous temperature of the polymer material.

(45) Hence, the temperature of the first liquid filled in the preform can be chosen to have a temperature between 10 C. and 100 C.

(46) Concerning the timing of filling the preform with the first liquid, several alternatives can be considered according to the production line of the filled container.

(47) According to another embodiment of the present invention (not represented), the preform is filled at the time the preform is being heated. Therefore step A and B (previously defined) are processed at the same time. It allows saving time in the process especially if the first liquid it at a temperature similar to the vitreous temperature of the preform's material.

(48) According to a further embodiment of the present invention (not represented), the preform is filled during the transfer of the heated preform in the mold: Step B takes place before step A and step A and C are processed at the same time.

(49) According to a further embodiment of the present invention (not represented), the preform is filled just before the liquid injection step takes place.

(50) Pumps, valve devices and control means used during the liquid injection blow molding process aiming at simultaneous forming and filling the container are not represented and not detailed but are part of the skilled person knowledge.

(51) Once the container is formed, the mold is opened by moving the two mold side halves away from each other so as to release container from the mold.

(52) Before the opening of the mold, the container is capped by a capping head (not represented). The capping head can be directly integrated in the injection blow molding apparatus.

(53) Alternatively, the container can be capped after the release of the container from the mold.

(54) FIG. 2 schematically represents an apparatus 1 in which is implemented a method for delivering a predetermined volume of a liquid end product in a container that has been obtained from a preform through a simultaneous blowing and filling process in which the preform is filled with the first liquid while the preform is disposed in the mold, according to a second embodiment of the present invention.

(55) The apparatus of FIG. 2 is similar to the one of FIG. 1 with the same references and same operating process, except in that the preform is filled just before the liquid injection step takes place while the heated preform 3 is disposed in the mold 2.

(56) FIG. 2 shows the preform 3 positioned in the mold 2 with the neck 3b of the preform lying on the upper face of the mold 2.

(57) In this second embodiment the preform's filling means 10 is integrated to the device comprising the injections means 6.

(58) The preform's filling means 10 comprises a filler 11 and a liquid filling circuit 12 in order to bring the first liquid stored in the filler 11 to the preform 3.

(59) The liquid filling circuit 12 is positioned near to the injection nozzle 7 or can be integrated into the injection nozzle 7.

(60) Integration of the liquid filling circuit 12 into the injection nozzle 7 leads to a reduced sized device.

(61) In this embodiment, the preform 3 is conventionally heated and positioned in the mold 2 (similar to the one of the first embodiment). According to the invention the preform 3 is then filled with the first liquid prior to the liquid injection step in which the second liquid is injected in the preform to expand it in the mold's cavity 4 to form the final container.

(62) As mentioned in the context of the first embodiment, the first liquid can be heated (between 10 C. and 100 C.) according to the working process.

(63) The first liquid has the same characteristics as the ones presented in the context of the embodiment of FIG. 1.

(64) Although the invention has been described by way of example, it should be appreciated that variations and modifications may be made without departing from the scope of the invention as defined in the claims. Furthermore, where known equivalents exist to specific features, such equivalents are incorporated as if specifically referred in this specification.