VEHICLE TANK AND MANUFACTURING METHOD FOR A VEHICLE TANK

Abstract

A vehicle tank, in particular for holding a fuel, in particular gasoline and/or diesel fuel, having: a first and a second partial shell, wherein the first and second partial shell are connected to one another in a partial shell joining area, and a barrier layer substantially, preferably completely, covering an outer surface of the first partial shell and an outer surface of the second partial shell, respectively, wherein the barrier layer spans the partial shell joining area on an outer surface of the vehicle tank.

Claims

1-13. (canceled)

14. A vehicle tank, in particular for holding a fuel, especially preferably a gasoline and/or diesel fuel, comprising: a first and second partial shell, wherein the first and second partial shell, are connected in a partial shell joining area, and a barrier layer covering an outer surface of the first partial shell and an outer surface of the second partial shell in each case substantially completely, wherein the barrier layer spans the partial shell joining area on an outer surface of the vehicle tank.

15. The vehicle tank according to claim 14, wherein the barrier layer covering the outer surface of the first partial shell and the outer surface of the second partial shell completely.

16. The vehicle tank according to claim 14, wherein the barrier layer is applied at least in portions by coating, overmolding, in particular at low pressure, and/or painting with a coating and/or a, in particular liquid, plastic and/or resin, and/or by immersion in a coating and/or liquid plastic and/or resin, wherein the coating and/or the, in particular liquid, plastic and/or resin preferably is a barrier material, at least after curing.

17. The vehicle tank according to claim 14, wherein the barrier layer comprises a barrier film layer.

18. The vehicle tank according to claim 17, wherein a barrier film layer comprises an EVOH layer, and/or wherein the barrier film layer is a multi-layer film, in which preferably the EVOH layer is covered on at least one side by a cover layer, wherein the cover layer is in particular made of a material that is compatible with the material of the first and/or second partial shell, wherein a respective adhesion promoter layer is preferably arranged between the cover layer or any cover layer and the EVOH layer.

19. The vehicle tank according to claim 18, wherein the barrier film layer comprises a first barrier film layer portion and a second barrier film layer portion, wherein the first barrier film layer portion is arranged at an outer surface of the first partial shell, and the second barrier film layer portion is arranged at an outer surface of the second barrier film layer portion, and wherein the first barrier film layer portion is preferably formed separately from the second barrier film layer portion.

20. The vehicle tank according to claim 17, wherein the barrier film layer comprises a first barrier film layer portion and a second barrier film layer portion, wherein the first barrier film layer portion is arranged at an outer surface of the first partial shell, and the second barrier film layer portion is arranged at an outer surface of the second barrier film layer portion, and wherein the first barrier film layer portion is preferably formed separately from the second barrier film layer portion.

21. The vehicle tank according to claim 20, wherein the first barrier film layer portion is arranged on the outside of the first partial shell with a back injection molding process when forming the first partial shell, and/or wherein the second barrier film layer portion is arranged on the outside of the second partial shell with a back injection molding process when forming the second partial shell.

22. The vehicle tank according to claim 21, wherein a section of the first barrier film layer portion overlaps a section of the second barrier film layer portion, in particular within the partial shell joining area in an overlap area.

23. The vehicle tank according to claim 20, wherein a section of the first barrier film layer portion overlaps a section of the second barrier film layer portion, in particular within the partial shell joining area in an overlap area.

24. The vehicle tank according to claim 23, wherein the section of the first barrier film layer portion extends substantially parallel to the section of the second barrier film layer portion within the overlap area.

25. The vehicle tank according to claim 24, wherein the section of the first barrier film layer portion extends in transverse direction in the overlap area to a main outer surface contour of the vehicle tank defined by the outer surfaces of the first and second partial shell, or wherein the section of the first barrier film layer portion substantially extends parallel to a main outer surface contour of the vehicle tank defined by the outer surfaces of the first and second partial shell within the overlap area.

26. The vehicle tank according to claim 25, wherein the section of the first barrier film layer portion is connected to the section of the second barrier film layer portion in the overlap area.

27. The vehicle tank according to claim 26, wherein the section of the first barrier film layer portion is connected by at least one of welding, gluing, and overmolding with a plastic material to the section of the second barrier film layer portion in the overlap area.

28. The vehicle tank according to claim 23, wherein the section of the first barrier film layer portion is connected to the section of the second barrier film layer portion in the overlap area.

29. The vehicle tank according to claim 28, wherein the section of the first barrier film layer portion is connected by at least one of welding, gluing, and overmolding with a plastic material to the section of the second barrier film layer portion in the overlap area.

30. The vehicle tank according to claim 20, wherein the first barrier film layer portion is spaced apart from the second barrier film layer portion at least in portions, and wherein the barrier layer also includes a barrier structure, which spans a gap area, in which the first barrier film layer portion is spaced apart from the second barrier film layer portion.

31. The vehicle tank according to claim 30, wherein the barrier structure comprises a plastic layer, formed by overmolding, in particular by low-pressure overmolding with a plastic material that is a barrier material, which plastic layer spans a gap area, wherein the plastic layer preferably overlaps the first barrier film layer portion and/or the second barrier film layer portion and/or wherein the barrier structure comprises an additional barrier film layer portion that spans the gap area, wherein said barrier film layer portion preferably forms another respective overlap area with the first barrier film layer portion and/or the second barrier film layer portion, wherein the additional barrier film layer portion is preferably connected, in particular welded and/or glued and/or joined by overmolding with a plastic material, in the respective or in each overlap area to the allocated first barrier film layer portion or the allocated second barrier film layer portion.

32. A method for manufacturing a vehicle tank according to claim 14, comprising the steps: Forming a first partial shell and forming a second partial shell of the vehicle tank, connecting the first and second partial shell in a partial shell joining area, and spanning the partial shell joining area, at an outer surface of the vehicle tank with a barrier layer, wherein the barrier layer preferably covers each of an outer surface of a first partial shell and an outer surface of the second partial shell substantially completely, preferably completely.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The invention may take physical form in certain parts and arrangement of parts, a preferred embodiment of which will be described in detail and illustrated in the accompanying drawings which forms a part hereof and wherein:

[0041] FIG. 1 a schematic cross-sectional view of a first embodiment of a vehicle tank,

[0042] FIG. 2 a schematic cross-sectional view of a second embodiment of a vehicle tank during the manufacturing process,

[0043] FIG. 3 based on a magnified detail of FIG. 2, a step of compressing sections of barrier film layer portions,

[0044] FIG. 4 a magnified detail from FIG. 3 after completing the manufacturing process, wherein the method of FIG. 3 was used to span the partial shell joining area with the barrier layer,

[0045] FIG. 5 a magnified detail from FIG. 2 after completing the manufacturing process, wherein a second method was used to span the partial shell joining area with the barrier layer,

[0046] FIG. 6 a magnified detail from FIG. 2 after completing the manufacturing process, wherein a third method was used to span the partial shell joining area with the barrier layer,

[0047] FIG. 7 a magnified detail from FIG. 2 after completing the manufacturing process, wherein a fourth method was used to span the partial shell joining area with the barrier layer,

[0048] FIG. 8 a layer assembly of a barrier film layer, and

[0049] FIG. 9 a layer arrangement of two welded barrier film layers.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0050] Referring now to the drawings wherein the showings are for the purpose of illustrating preferred and alternative embodiments of the invention only and not for the purpose of limiting the same, FIG. 1 shows a schematic cross-section through a first embodiment representing a vehicle tank 20, suitable for holding gasoline or diesel fuel, having a first partial shell 22 and a second partial shell 24, made of the same molding material, e.g. HDPE, in an injection molding process. The first partial shell 22 and the second partial shell 24 each have a flange 26, 28, which surrounds a respective opening 25, 27 of the first partial shell 22 or the second partial shell 24 in its circumferential direction, preferably completely. Flanges 26, 28 are bonded to one another, e.g. with laser welding or sonotrode welding and are therefore connected by a, preferably continuous, welding seam 30 made from the molding material. The flanges 26, 28, together with the welding seam 30, are an embodiment of the partial shell joining area 32. The vehicle tank 20, in particular the second partial shell 24, comprises a removal opening 34 and/or a filling opening 36 for the fuel. A selection 38a to 38e of the above-described functional and structural elements is arranged in the interior of the vehicle tank 20.

[0051] Furthermore, the vehicle tank comprises a barrier layer 40, for example made from a cured epoxy resin, which was applied by overmolding after the plasma surface treatment of the first and second partial shells 22, 24 on the outer surfaces of the first and second partial shells 22, 24, in such a way that they are covered substantially completely, and, especially preferably, completely with the barrier layer 40. The overmolding has also covered, and thereby spans, the partial shell joining area 32. The utilized epoxy resin is a barrier material in relation to the molding material of the partial shells 22, 24, for the preferred test substances listed above, in this example HDPE. The overmolding process forms an epoxy resin layer, which may be brought into full contact with a tool not shown above, heated to a temperature of approx. 80° C., which achieves quick curing of the epoxy resin layer and a solid bond with the partial shells 22, 24 and the partial shell joining area 32 so that an especially durable barrier layer 40 is established quickly.

[0052] FIG. 2 shows a schematic cross-section through a second embodiment of a vehicle tank 120, suitable for holding gasoline or diesel fuel, during the manufacturing process, wherein parts and elements corresponding to the first embodiment of the vehicle tank 20 have reference marks increased by 100 relating to their description in the first embodiment. The following section only discusses the differences of the first and the second embodiment. In the second embodiment, the barrier layer is formed by a barrier film layer 140. In spite of certain differences to the barrier layer 40, a reference mark increased by 100 is used due to the similarity in function.

[0053] In the second embodiment of the vehicle tank 120, the barrier layer is formed as a barrier film layer 140, as shown in FIG. 8, which is a multi-layer film having an EVOH layer 142 with a thickness of 80 μm to 100 μm that is covered on both sides by an HDPE cover layer 144, 146 with a thickness of 345 μm, respectively. An adhesion promoter layer 148, 150 with a thickness of approx. 5 μm, respectively, is arranged between the respective cover layer 144, 146 and the EVOH layer.

[0054] The barrier film layer 140 comprises a first barrier film layer portion 152, which is attached with a back injection molding process at the outer surface of the first partial shell 122, and a second barrier film layer portion 154, formed separately from the first barrier film layer portion 152, which is attached with a back injection molding process at the outer surface of the second partial shell 124.

[0055] A section 156, preferably arranged around the circumference of opening 125 of the first partial shell 122 and/or flange 128 of the first partial shell 122, extends from the surface of the first barrier film layer portion 152 in a direction away from an internal volume 158 of the first partial shell 122. A section 160, preferably arranged around the circumference of opening 127 of the second partial shell 124 and/or flange 126 of the second partial shell 124, extends from the surface of the second barrier film layer portion 154 in a direction away from an internal volume 162 of the second partial shell 124.

[0056] The first partial shell 122 and the second partial shell 124 are welded together, wherein the molding material of the first partial shell 122 and the second partial shell 124 is used to form a welding seam 164. This process preferably uses welding equipment featuring rounded contact contours so that rounded external welding marks 166, 168 can be formed in the flanges 126, 128 during welding as shown by the dashed lines in FIGS. 3 to 7 to avoid damaging the barrier film layer 140. The welding marks 166, 168 may be preshaped when forming the first partial shell 122 and/or the second partial shell 124 for safe placement of the contact contours without damaging the barrier film layer 140 at the flanges 126, 128. The welding described with reference to FIG. 3 can also be used in the embodiments of FIGS. 5, 6 and 7.

[0057] FIG. 3 uses a magnified detail of FIG. 2, marked as the dotted area G in FIG. 2, to show a step of compressing a section 156 of the first barrier film layer portion 152 and a section 160 of the second barrier film layer portion 154 in an overlap area 170a, with simultaneous use of hot air from the nozzles 172, 174 so that the sections 156, 160 overlap in the overlap area 170a (see FIG. 4) and are substantially aligned parallel to one another. The nozzles 172, 174 are preferably attached to the tools 180, 182 that bear the hot plates 176, 178. While the nozzles 172, 174 compress sections 156, 160 with air, the tools 180, 182 are preferably approximated in such a way that the hot plates 176, 178 weld together the sections 156, 160 in a welding area 184a, as closely as possible to the flanges 126, 128. In this manner, the barrier film layer 140 spans the partial shell joining area 132 as a barrier layer on an outer surface of the vehicle tank 120, as shown in FIG. 4. The welding area 184a preferably extends along an outer circumference of the vehicle tank along the partial shell joining area 132.

[0058] The overlap area 170a is located within the partial shell joining area 132. The overlap area 170a, as well as the subsections of sections 156, 160 arranged therein, extends in transverse direction, preferably substantially perpendicular, to one of the outer surfaces 188, 189 of the main outer contour HK of the vehicle tank, indicated by a dashed line, which is defined by the first and second partial shell 122, 124 and covered by the barrier film layer 140. The main extension direction HEa of the welding area 184a extends preferably in transverse direction, in particular substantially perpendicular to the main outer contour HK.

[0059] FIG. 5 shows the magnified detail of FIG. 2, marked as the dotted area G in FIG. 2, wherein a second method was used for spanning the partial shell joining area 132 with the barrier layer in the finished vehicle tank. This method involves compressing the first and second section 156, 160 by folding the second section 160 with the use of hot air, for example from an air nozzle corresponding to nozzle 174, until it clings to the partial shell joining area 132. After that, section 156 is folded with the use of hot air, for example from an air nozzle corresponding to nozzle 172, until it clings to section 160, in such a way that it extends in an overlap area 170b parallel to section 160. Sections 156, 160 are welded together by using a hot plate or a hot roller 190, which results in a welded section 184b. In this manner, the barrier film layer 140 in this embodiment spans the partial shell joining area 132 as a barrier layer at an outer surface of the vehicle tank 120. A main extension direction HEb of the welded area 184b extends, preferably along with the overlap area 170b and/or the adjoining subsections of sections 156, 160, preferably substantially parallel to the main outer contour HK.

[0060] FIG. 6 shows the magnified detail of FIG. 2, marked as the dotted area G in FIG. 2, wherein a third method was used for spanning the partial shell joining area 132 with the barrier layer in the finished vehicle tank. In this embodiment, the barrier layer comprises a barrier structure, which is formed as an additional barrier film layer portion 192. During the manufacturing process, the first and second sections 156, 160 are cut within the partial shell joining area 132 in such a way that they are spaced apart with a gap area 194 from one another. In a next step, the additional barrier film layer portion 192 is arranged in such a way that it forms both the first section 156 and the second section 160 of an allocated overlap area 170c′, 170c″, wherein preferably in each of the overlap areas 170c′, 170c″ the additional barrier film layer portion 192 extends parallel to the first section 156 or the second section 160 and preferably, to the main outer contour HK. In this manner, the barrier structure spans the gap area 194. By using a hot plate or a hot roller 190, section 156 is welded to the additional barrier film layer portion 192 in the overlap area 170c′, forming a welded area 184c, and section 160 is welded in the same work step to the additional barrier film layer portion 192 in the overlap area 170c″, forming a welded area 184c″, using a hot plate or hot roller 190. The welded areas 184c′, 184c″ extend along a common main extension direction HEc, which substantially runs parallel to the main outer contour HK.

[0061] FIG. 7 shows the magnified detail of FIG. 2, marked as the dotted area G in FIG. 2, wherein a fourth method was used for spanning the partial shell joining area 132 with the barrier layer in the finished vehicle tank. In this embodiment, the barrier layer further comprises a barrier structure comprising a plastic layer 196 that is generated by overmolding with PK or is formed therefrom. During the manufacturing process, the first and second sections 156, 160 are cut within the partial shell joining area 132 in such a way that they are spaced apart with a gap area 194 from one another. In a further step, the partial shell joining area 132 is overmolded with PK in such a way that the molded material forms the continuous plastic layer 196, which fully connects the first and second section 156, 160 in the circumferential direction of the vehicle tank and which in particular overlaps the first and second section 156, 160. After the curing of the PK, the barrier structure is formed, since PK in particular is a barrier material with reference to HDPE for the preferred test substances listed above.

[0062] In the embodiments described above, the barrier film layer 140 preferably is a multi-layer film with an EVOH layer. The welding of two barrier film layers, which can be formed as two multi-layer films each with an EVOH layer, as two single-layer films each with an EVOH layer, or as a multi-layer film and a single-layer film, in each case formed with an EVOH layer, preferably establishes a material bridge between the EVOH layers, which is present in the connection of the barrier film layers. The material bridge itself preferably is made of EVOH or at least comprises EVOH to tightly join the EVOH layers to one another. The material bridge between the EVOH layers is preferably formed in one, a plurality, or each of the welding areas 184a, 184b, 184c′ and 184c″.

[0063] A welding step as described above of a first barrier film layer 140a with a second barrier film layer 140b, in each case formed as multi-layer films, is shown in FIG. 9. The barrier film layers 140a, 140b each comprise the barrier film layer structure discussed in connection with FIG. 8, with an EVOH layer 142a, 142b, respectively, two HDPE cover layers 144a, 146a; 144b, 146b, respectively, and two adhesion promoter layers 148a, 150a, 148b, 150b, respectively. A connection generated by welding the first barrier film layer 140a to the first barrier film layer 140b comprises at least one material bridge A, comprising EVOH or made therefrom, between the EVOH layers 142a, 142b of the barrier film layers 140a, 140b. Furthermore, at least one material bridge, preferably two material bridges B, B′ can be formed between the adhesion promoter layers 150a, 150b in such a welding formation, wherein preferably one or all of the material bridges B, B′ comprise the material of the adhesion promoter layers 150a, 150b, e.g., AMP, or are made therefrom. Likewise, at least one material bridge and preferably two material bridges C, C′ can be formed between the cover layers 146a, 146b in such a welding formation, wherein preferably one or all of the material bridges C, C′ comprise the material of the cover layers, such as HDPE, or are made therefrom.

[0064] Each of the overlap areas 170a, 170b, 170c′, 170c″ is located within the partial shell joining area 132.

[0065] While considerable emphasis has been placed on the preferred embodiments of the invention illustrated and described herein, it will be appreciated that other embodiments, and equivalences thereof, can be made and that many changes can be made in the preferred embodiments without departing from the principles of the invention. Furthermore, the embodiments described above can be combined to form yet other embodiments of the invention of this application. Accordingly, it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.