USE OF A PLASTIC CONTAINING ANTIMICROBIAL ACTIVE SUBSTANCE TO MANUFACTURE FLUID-STORING AND/OR -CARRYING MOTOR VEHICLE COMPONENTS

Abstract

Use of a plastic containing an antimicrobial active substance to manufacture motor vehicle components that are embodied to store and/or to convey fluids.

Claims

1-10. (canceled)

11. Use of a plastic containing an antimicrobial active substance to manufacture motor vehicle components that are embodied to store and/or to convey associated fluids.

12. The use according to claim 11, wherein the plastic comprises an antimicrobial masterbatch that is mixed into the plastic.

13. The use according to claim 12, wherein the plastic is a thermoplastic.

14. The use according to claim 13, wherein the plastic is at least one of a thermoplastic elastomer and a polyolefin.

15. The use according to claim 11, wherein the plastic is a thermoplastic.

16. The use according to claim 15, wherein the plastic is at least one of a thermoplastic elastomer and a polyolefin.

17. The use according to claim 11, wherein the antimicrobial active substance is coupled to a tracing substance.

18. The use according to claim 17, wherein the tracing substance includes at least one of a color pigment, a fluorescent pigment and ferromagnetic particles.

19. A motor vehicle component that is embodied to store and/or to convey fluid, for example, a tank, a conveying tube, and/or a conveying hose, wherein the motor vehicle component comprises, at least on its boundary surface wetted by an associated fluid during operation as intended, a plastic that contains an antimicrobial active substance.

20. The motor vehicle component according to claim 19, wherein the plastic is at least constituted from a plastic that is free of antimicrobial active substance, and from an antimicrobial masterbatch mixed into the active substance-free plastic.

21. The motor vehicle component according to claim 20, wherein a wall of the motor vehicle component which comprises the boundary surface is constituted over its entire thickness from the plastic having an antimicrobial active substance.

22. The motor vehicle component according to claim 19, wherein a wall of the motor vehicle component which comprises the boundary surface is constituted over its entire thickness from the plastic having an antimicrobial active substance.

23. A method for manufacturing a motor vehicle component according to claim 19, wherein the method comprises the following steps: mixing an antimicrobial active substance into a plastic reshaping the plastic, comprising the antimicrobial active substance, into at least a portion of the motor vehicle component embodied to store and/or to convey fluid, in such a way that the portion constitutes at least one boundary surface, wetted by fluid in the context of operation of the motor vehicle component as intended, of the motor vehicle component.

24. The method according to claim 23, wherein the mixing step is mixing the antimicrobial active substance into a plastic granulate.

25. The method according to claim 23, wherein the reshaping step encompasses manufacture of a tank body and/or of a tubular body and/or of a hose body.

26. The method according to claim 23, wherein the reshaping step includes melting of the plastic into a melted plastic and a step of blow-reshaping and/or injection molding and/or extruding the melted plastic.

27. The method according to claim 24, wherein the reshaping step includes melting the plastic granulate into a melted plastic, and a step of blow-reshaping and/or injection molding and/or extruding the melted plastic.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0026] 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 drawing which form a part hereof and wherein:

[0027] FIG. 1 shows a liquid tank as an example of a fluid-storing motor vehicle component.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0028] Referring now to the drawing 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 liquid tank according to the present invention that is labeled in general as 10. Liquid tank 10 preferably encompasses an upper shell part 12 that comprises a filler opening 14 having a flanged rim 16 surrounding filler opening 14. A filler conduit, for example a filling tube (not depicted in FIG. 1), can be connected to flanged rim 16.

[0029] Liquid tank 10 furthermore encompasses a lower shell part 18 that comprises a withdrawal opening 20 having a flanged rim 22 surrounding withdrawal opening 20. A withdrawal conduit (not depicted in FIG. 1) can in turn be connected to flanged rim 22.

[0030] Upper shell part 12 and lower shell part 19 are preferably joined to one another, for example adhesively bonded or welded, along a respective peripheral joining flange 24, 26. Joining flanges 24 and 26 contact one another along a joining surface 28 that is preferably flat.

[0031] Tank 10 comprises a tank wall 30 that surrounds a tank volume 32 of tank 10. Tank wall 30 is constituted on the one hand by wall 34 of upper shell part 12, and constituted on the other hand by wall 36 of lower shell part 18.

[0032] An inner side 30a of tank wall 30 constitutes a delimiting surface of the tank wall with respect to tank volume 32. Inner side 30a in turn is constituted on the one hand by inner side 34a of wall 34 of upper shell part 12, and constituted on the other hand by inner side 36a of wall 36 of lower shell part 18.

[0033] In a departure from the example depicted, liquid tank 10 can of course comprise more than two shell parts, or can also be embodied in one piece, for example by blow molding.

[0034] In a bottom portion 38 of tank 10, more precisely of lower shell part 18, a relief structure 40 is shaped, on inner side 30a facing toward tank volume 32 or 36a, so as to face toward tank volume 32. Relief structure 40 is shaped integrally and materially continuously with tank 10, in particular with lower shell part 18.

[0035] Like upper shell part 12, lower shell part 18 is preferably manufactured by injection molding.

[0036] In the example depicted, relief structure 40 formed directly upon injection molding of lower shell part 18 encompasses identical protrusions 42 that project in a protrusion direction V into tank volume 32, away from bottom portion 38 of lower shell part 18. In the example depicted, projections 42 extend parallel to one another, with a substantially uniform height regardless of location, in an extension direction orthogonal to the drawing plane of FIG. 1. For example, projections 42 can also extend a little way along side wall 44 toward joining surface 28, so that they have a greater height at side wall 44 than in a portion between mutually oppositely located side walls which is located at a distance from side wall 44.

[0037] Directly adjacent projections 42 are arranged at a distance from one another by way of spacings 46 in a direction orthogonal both to protrusion direction V and to the extension direction of projections 42. The spacing direction in FIG. 1 is parallel to the drawing plane. The projections can exhibit, in their extent between two side walls, one or two passages in order to allow spillover from a region between two projections into an adjacent region of that kind. The passages preferably have an unobstructed width that is no greater than twice the average thickness of the projection. Passages of projections immediately adjacent to one another are preferably embodied with an offset from one another in a longitudinal direction of the projections, so that liquid cannot flow in a straight line, without deflection, past two directly adjacent projections.

[0038] In the example depicted, all projections 42 are preferably identical to one another, as are spacings 46 between adjacent projections 42.

[0039] In the example depicted, spacings 46 are slightly larger than the thickness, to be measured in the same direction, of projections 42. Spacings 46 are dimensioned so that they are too large for the formation of capillary effects between mutually facing side walls of directly adjacent projections 42, and so that they are too small for the formation of appreciable liquid flows in a spacing direction in the sub-volumes located between directly adjacent projections 42.

[0040] The thickness of projections 42 is selected so that they are stable over the expected operational service life of liquid tank 10.

[0041] In terms of the selection of usual materials for manufacturing upper shell 12 and lower shell 18, i.e. for example thermoplastics, an optimum ratio that results between projection thickness and spacing 46, to be measured in the same direction, between two adjacent projections 42 is approximately from 0.2 to 3. In the example depicted, the ratio of projection thickness to spacing 46 is slightly less than 1, approximately 0.85, since spacing 46 is slightly larger than the thickness of the associated projections 42.

[0042] Shell parts 12 and 18 can each be manufactured in an injection mold in one step, and then joined to one another at their joining flanges 24 and 26. Relief structure 40 is constituted directly during reshaping manufacture of lower shell part 18. This eliminates any need to configure a relief structure on a separate component and connect the component to one of shell parts 12 and 18, thus minimizing the outlay for manufacturing liquid tank 10 presented here.

[0043] Alternatively, lower shell 18 can be configured without relief structure 40 and can have a smooth bottom.

[0044] According to the present invention, at least lower shell part 18 is, preferably both shell parts 12 and 18 are, constituted from a thermoplastic material that contains an antimicrobial active substance, for example a silver compound or a zinc compound. It is thereby possible to prevent microbial pathogens from reproducing in the tank or in conduits connecting thereto, and contaminating or infecting humans.

[0045] For this purpose, in simple fashion a plastic granulate that is free of antimicrobial active substance can be procured and can be mixed with an antimicrobial masterbatch prior to reshaping. Further additives, for example color pigments, can additionally be mixed in as necessary or as desired. The colored or fluorescent pigments are preferably coupled to the antimicrobial active substance so that the completed component can be checked with a color spectrometer for the presence of a correct quantity of antimicrobial active substance.

[0046] In principle, liquid tank 10 depicted in FIG. 1 can receive any liquids, in particular operating liquids of motor vehicles. Particularly preferably, liquid tank 10 is a water tank that is embodied and intended for the reception of water that is in turn intended for injection into the internal combustion engine in the motor vehicle. Water injection serves to reduce emissions and/or to decrease knock susceptibility.

[0047] Because the liquid contained therein is injected into the exhaust system, this water tank does not represent an immediate risk of contamination or infection for the occupants of the vehicle carrying the tank; but on the one hand a maintenance person may come into contact with bacterially contaminated liquid, and on the other hand microorganisms that have sufficiently reproduced can undesirably clog conduits and/or nozzles and/or filters and/or pumps, and/or can attack material involved in the injection apparatus, and thereby interfere with injection.

[0048] A further advantageous use of the present invention consists in the constitution of storage and conveyance components of motor vehicle climate-control systems from plastic equipped with antimicrobial active substance. The conduits of the motor vehicle climate control system deliver climate-controlled, in particular moisture-conditioned, air into the passenger compartment of a motor vehicle, with the result that that air is directly inhaled by occupants and thereby travels into their bodies.

[0049] During a shutoff phase of the motor vehicle, condensation water can condense onto the conduit walls; without the feature proposed according to the present invention, microbial germs can reproduce in that water and can be blown into the passenger compartment when the climate control system is again put into service. Germ reproduction in the conduits can be effectively suppressed or even prevented by the use of a plastic to which antimicrobial active substance has been added.

[0050] 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.