Liquid container and method for manufacturing a liquid container

Abstract

A liquid container for a motor vehicle, having a first half-shell and a second half-shell, the half-shells delimiting a storage volume for accommodating liquid, the first half-shell having a first support layer and a first barrier layer, the second half-shell having a second support layer and a second barrier layer, the first barrier being situated on a side of the first support layer facing the storage volume, and the second barrier layer being situated on a side of the second support layer facing the storage volume.

Claims

1. A liquid container for a motor vehicle comprising: a first half-shell; and a second half-shell; wherein the half-shells delimit a storage volume for accommodating liquid; wherein the first half-shell has a first support layer and a first barrier layer; wherein the second half-shell has a second support layer and a second barrier layer; wherein the first barrier layer is situated on a side of the first support layer facing the storage volume; wherein the second barrier layer is situated on a side of the second support layer facing the storage volume; wherein the half-shells in a connecting area are directly integrally joined together, the first barrier layer in the connecting area being directly integrally joined to the second barrier layer; wherein the first support layer and the second support layer in the connecting area are spaced apart from one another, with no contact between the first support layer and the second support layer, and the support layers bordering the barrier layers on both sides; and wherein a plastic that is used for attaching molded elements, connecting parts, or functional units is locally molded onto a side of at least one of the barrier layers facing the storage volume.

2. The liquid container according to claim 1, wherein: the first barrier layer in the connecting area being directly integrally bonded to the second barrier layer.

3. The liquid container according to claim 1, wherein at least one of the half-shells in the connecting area is made, at least partially, of a laser-transparent material, a direct integral bond having been formed by laser transmission welding.

4. The liquid container according to claim 3, wherein: the first support layer in the connecting area is made, at least partially, of a laser-transparent material, or the first support layer and the first barrier layer in the connecting area are made, at least partially, of a laser-transparent material.

5. The liquid container according to claim 1, wherein: at least one of the half-shells in the connecting area has a web; and wherein a direct integral bond is formed along the web.

6. The liquid container according to claim 1, wherein: at least one of the barrier layers is a one-ply film that has been directly integrally bonded to the associated support layer; and/or at least one of the barrier layers is a multi-ply film that has been directly integrally bonded to the associated support layer.

7. A liquid container for a motor vehicle comprising: a first half-shell; and a second half-shell; wherein the half-shells delimit a storage volume for accommodating liquid; wherein the first half-shell has a first support layer and a first barrier layer; wherein the second half-shell has a second support layer and a second barrier layer; wherein the first barrier layer is situated on a side of the first support layer facing the storage volume; wherein the second barrier layer is situated on a side of the second support layer facing the storage volume; wherein the half-shells in a connecting area are integrally joined together, the first support layer in the connecting area being integrally joined to the second support layer; wherein the first barrier layer and the second barrier layer in the connecting area are spaced apart from one another, with no contact between the first barrier layer and the second barrier layer; wherein solidified melt of a material of the first support layer and/or of a material of the second support layer is situated between the barrier layers; wherein a permeation path is formed in the connecting area between the spaced-apart barrier layers; wherein a length of the permeation path, viewed in a cross section, is greater than or equal to twice the width of the permeation path; and wherein the width of the permeation path corresponds to the distance between the barrier layers in the connecting area.

8. The liquid container according to claim 7, wherein: the first support layer in the connecting area being integrally bonded to the second support layer.

9. The liquid container according to claim 7, wherein the barrier layers in the connecting area are completely enclosed by the support layers and isolated from the surroundings by the support layers.

10. The liquid container according to claim 7, wherein: at least one of the half-shells in the connecting area has a web; and wherein an integral bond is formed along the web.

11. The liquid container according to claim 7, wherein: at least one of the barrier layers is a one-ply film that has been integrally bonded to the associated support layer; and/or at least one of the barrier layers is a multi-ply film that has been integrally bonded to the associated support layer.

12. The liquid container according to claim 7, wherein a plastic that is used for attaching molded elements, connecting parts, or functional units is locally molded onto a side of at least one of the barrier layers facing the storage volume.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is described in greater detail below with reference to the drawings, which schematically illustrate one exemplary embodiment, as follows:

(2) FIG. 1 shows a liquid container according to the invention in a cross section;

(3) FIG. 2 shows the manufacture of the liquid container from FIG. 1;

(4) FIG. 3 shows another liquid container according to the invention in a cross section;

(5) FIG. 4 shows the manufacture of the liquid container from FIG. 3;

(6) FIG. 5 shows another liquid container according to the invention in a cross section and its manufacture; and

(7) FIG. 6 shows another liquid container according to the invention in a cross section and its manufacture.

DETAILED DESCRIPTION

(8) FIG. 1 shows a liquid container 2 according to the invention for a motor vehicle, in a cross section. The liquid container 2 has a first half-shell 4 and a second half-shell 6. The half-shells 4, 6 delimit a storage volume 8 for accommodating liquid 10.

(9) In the present case the liquid container 2 is a plastic fuel container 2 for a motor vehicle. In the present case the liquid 10 is fuel 10 for driving an internal combustion engine.

(10) The first half-shell 4 has a first support layer 12 and a first barrier layer 14. The second half-shell 6 has a second support layer 16 and a second barrier layer 18. The first barrier layer 14 is situated on a side 20 of the first support layer 12 facing the storage volume 8. The second barrier layer 18 is situated on a side 22 of the second support layer 16 facing the storage volume 8.

(11) The first barrier layer 14 essentially completely covers the side 20 of the first support layer 12 facing the storage volume 8. The second barrier layer 18 essentially completely covers the side 22 of the second support layer 16 facing the storage volume 8.

(12) The half-shells 4, 6 are integrally joined together in a connecting area 24. The first barrier layer 14 is integrally joined to the second barrier layer 18 in the connecting area 24.

(13) The first support layer 12 and the second support layer 16 are spaced apart from one another in the connecting area 24, with no contact between the first support layer 12 and the second support layer 16, and the support layers 12, 16 bordering the barrier layers 14, 18 on both sides. It is understood that the connecting area 24 represents a fully circumferential, self-contained integral bond, so that the half-shells 4, 6 form an essentially closed tank bladder.

(14) As mentioned above, the essentially closed tank bladder has mandatory inlets and outlets, not illustrated, for filling, withdrawing, and venting, in the vicinity of which a barrier layer is locally interrupted.

(15) As is apparent from FIG. 2, the first half-shell 4 in the connecting area 24 is made, at least partially, of a laser-transparent material, wherein the integral bond between the half-shells 4, 6 has been established by laser transmission welding with the aid of a laser welding device 26.

(16) In the present example, the first support layer 12 in the connecting area 24 is made, at least partially, of a laser-transparent material. According to further exemplary embodiments of the invention, it may be provided that the first support layer is made completely of laser-transparent material. According to further embodiments, it may likewise be provided that the first support layer and the first barrier layer in the connecting area are made, at least partially, of laser-transparent material.

(17) The half-shells 4, 6 have a web 28, 30, respectively, in the connecting area 24. The integral bond between the barrier layers 14, 18 is formed along the webs 28, 30. The webs 28, 30 are circumferential webs 28, 30, each extending with a lateral protrusion in order to provide a defined contact between the half-shells 4, 6 to form a weld joint. The webs 28, 30 may be referred to as weld collars 28, 30.

(18) In the present case the barrier layers 14, 18 are one-ply films that have been integrally joined to the associated support layer 12, 16 in the injection molding process. According to further exemplary embodiments of the invention, it may be provided that at least one barrier film, in particular both barrier films, has/have a multi-ply design, and, for example, may have a five-ply wall structure with a central EVOH layer, two LDPE layers that cover the EVOH layer, and two HDPE layers that cover the LDPE layers.

(19) A plastic 34 that is used for attaching a surge tank 36 has been locally molded onto a side 32 of the barrier layer 18 facing the storage volume 8. The plastic 34 forms a pedestal 34 to which the surge tank 36 has been welded. The surge tank 36 has thus been integrated into the storage volume 8 without adversely affecting the structural integrity of the barrier layer 18.

(20) Similarly, a plastic 40 that is used for attaching molded elements, connecting parts, or functional units has been molded onto a side 38 of the barrier layer 14 facing the storage volume 8.

(21) FIG. 3 shows another embodiment of a liquid container 42 according to the invention, in a cross section. To avoid repetition, in comparison to the above-described exemplary embodiments, identical features are assigned the same reference numerals.

(22) The liquid container 42 differs from the liquid container 2 in that the half-shells 4, 6 in a connecting area 44 are integrally joined together, the first support layer 12 in the connecting area 44 being integrally joined to the second support layer 16.

(23) The first barrier layer 14 and the second barrier layer 18 are spaced apart from one another in the connecting area, with no contact between the first barrier layer 14 and the second barrier layer 18. A solidified melt 46 of a material of the first support layer 12 and of the second support layer 16 is situated between the barrier layers 14, 18. It is understood that this results in local mixing of the material of the first support layer 14 and of the second support layer 16 in the connecting area 44.

(24) In the connecting area 44, the barrier layers 14, 18 are completely enclosed by the support layers 12, 16 and isolated from the surroundings U by the support layers 12, 16. A width b of a permeation path 48 corresponds to the distance between the barrier layers 14, 18. Viewed in the cross section in the present case, a length 1 of the permeation path 48 is more than twice the width b of the permeation path 48.

(25) As is apparent from FIG. 4, the liquid container 42 has been manufactured by hot plate welding. For this purpose, the half-shells 4 and 6 provided in the injection molding have been initially heated in the connecting area 44 by means of a hot plate 50.

(26) For this purpose, protrusions 52, 54 formed in particular on the webs 28, 30 have been plasticized. In a next step the half-shells 4, 6 have been pressed together, with plasticized material of the protrusions 52, 54 being pressed between the barrier layers 14, 18. During the pressing together of the half-shells 4, 6, a sealing element 56 is placed against an end-face side 58 of the webs 28, 30.

(27) FIG. 5 shows another variant of a liquid container 60 according to the invention. The liquid container 60 differs from the above-described exemplary embodiments by virtue of the asymmetrical design of the first half-shell 4 compared to the second half-shell 6. In the present case the first half-shell 4 forms a cover of the second half-shell 6.

(28) In addition, a first barrier layer 62 and a second barrier layer 64 having a five-ply structure are provided. The first barrier layer 62 has a central layer made of EVOH, which is covered on both sides by adhesion promoter layers made of LDPE. The LDPE layers are in turn bordered on both sides by HDPE layers.

(29) The five-ply barrier film 62 formed in this way has been integrally joined to the first support layer 12 in the injection molding process. The first support layer 12 is likewise made of an HDPE, the integral bond being the same between the first support layer 12 and the first barrier layer 62.

(30) As illustrated in the top part of FIG. 5, the first half-shell 4 and the second half-shell 6 are initially provided separately. In a second step the first half-shell 4 and the second half-shell 6 are pressed together and integrally joined by means of a laser welding device 26, as discussed above with reference to FIG. 2.

(31) Also as in the example in FIG. 2, the first support layer 12 and the second support layer 16 of the liquid container 60 are spaced apart from one another in the connecting area 24. Therefore, there is no direct contact between the first support layer 12 and the second support layer 16.

(32) The first barrier layer 14 and the second barrier layer 18 form an essentially closed barrier bladder around the storage volume 8, with the previously discussed limitations for any inlets and outlets for fluid streams.

(33) FIG. 6 shows another variant of a liquid container 66 according to the invention. In this exemplary embodiment the first half-shell 4 and the second half-shell 6 have an asymmetrical design, with the first half-shell forming a cover of the second half-shell 6.

(34) The first half-shell 4 and the second half-shell 6 have been welded together by hot plate welding by means of a hot plate 50, analogously to the exemplary embodiment discussed for FIG. 4.

(35) For this purpose, local protrusions 68, 70 of the half-shells 4, 6, respectively, have been plasticized by means of the hot plate. The hot plate 50 has been subsequently removed and the half-shells 4, 6 pressed together, with plasticized material of the protrusions 68, 70 being pressed between multi-ply barrier layers 62, 64. The barrier layers 62, 64 are thus spaced apart from one another, with no direct contact between the barrier layers 62, 64. A permeation path 48 is thus formed between the barrier layers 62, 64, analogously to FIG. 3.

LIST OF REFERENCE SYMBOLS

(36) 2 liquid container 4 first half-shell 6 [second] half-shell 8 storage volume 10 liquid 12 first support layer 14 first barrier layer 16 second support layer 18 second barrier layer 10 side 22 side 24 connecting area 26 laser welding device 28 web/weld collar 30 web/weld collar 32 side 34 plastic/pedestal 36 surge tank 38 side 40 plastic 42 liquid container 44 connecting area 46 solidified melt 48 permeation path 50 hot plate 52 protrusion 54 protrusion 56 sealing element 58 end-face side 60 liquid container 62 first barrier layer 64 second barrier layer 66 liquid container 68 protrusion 70 protrusion l length b width U surroundings