Title of Invention: A FUEL FILLER HOUSING FOR ENGINE

DRIVEN VEHICLES

[1] The present invention relates to a motor- vehicle fuel filler housing comprising a body made of a comparatively hard material and at least one seal that is made of a relatively soft material and is applied by two-component injection-molding to the housing body to seal off a motor vehicle component.

[2] Such motor- vehicle fuel filler housings are mounted to the motor vehicle body side.

In general a fuel conduit leading to the fuel tank terminates in the region of the housing body and is externally accessible to allow fueling the vehicle. A seal seals the housing body off the fuel tank neck. This seal prevents fuel from leaking out between the fuel tank neck and the housing body when refueling. Another seal may be present between the housing body and the vehicle body. The latter seal precludes fuel from leaking out of the housing body and furthermore protects the fuel filler housing from soiling.

[3] The European patent document EP 0 736 406 Al discloses a housing body of a fuel- tank valve module. The housing body is made of polypropylene (PP) preferably reinforced by mineral or glass fibers. Sealing elements implementing sealing relative to a fuel-tank neck and the car body are injection-molded onto the housing body. These elements are elastomeric, preferably being made of an ethylenepropylenediene rubber (EPDM).

[4] In the light of the above cited state of the art, the objective of the present invention is to create an economical housing body offering especially high mechanical strength.

[5] This problem is solved by features of the housing body of claim 1. Advantageous embodiment modes are defined in the dependent claims.

[6] The motor- vehicle fuel filler housing of the present invention comprises a body made of a comparatively hard material and at least one seal formed, by two-component injection molding, on the housing body and of a comparatively softer material to seal off a motor vehicle component, the comparatively harder material being a relatively hard polyvinylchloride (PVC) and the relatively softer material being a relatively soft polyvinylchloride (PVC).

[7] The housing body is affixable to the motor vehicle's body and may be tub-like. When the housing body is installed, the minimum of one seal is configured between this body and the motor vehicle component and there precludes the liquid and/or possible gaseous fuel from leaking.

[8] The present invention rests on the insight that the known fuel filler housings fitted with EPDM seals on one hand are expensive and on the other hand lack sufficient op- erational strength. In particular, where diesel fuels are used, the seals degrade in time in that the plastic is ultimately destroyed. Such drawbacks may be overcome by the invention employing relatively soft PVCs for the minimum of one seal. PVC materials are relatively economical. They may be processed with ease, and are highly resistant to fuels, especially also to diesel fuels. Moreover, the elasticity and softness of the PVC materials may be adjusted within wide limits by resorting to plasticizers. Consequently the properties of the minimum of one seal may be individually matched also to requirements set by the geometry of the fuel filler housing.

[9] Employing a relatively hard PVC for the housing body also offers a economical and highly resistant alternative to the conventional fiber-reinforced PP materials. Where desirable, the strength of the relatively hard PVC also may be adjusted by a controlled use of plasticizers.

[10] The two-component injection molding procedure is especially advantageously applicable in combination with the PVCs used in the manner of the invention as regards both the housing body and the minimum of one injection molded attached seal. The two PVC materials containing the same basic polymers, they shall be joined to each other in especially tightly linking manner. As a result, in some circumstances, the need for geometrically interlocking anchoring or other reinforcements in the junction's area may be dispensed with.

[11] In one embodiment mode of the present invention, the minimum of one seal is designed to seal off a fuel-tank neck. One more seal is used in a further embodiment mode, sealing off a body component to support the fuel filler housing. In this latter embodiment mode, the entire fuel filler housing inclusive the two seals may be integrally manufactured by injection molding.

[12] In a particular embodiment mode of the present invention, a hinge arm made of a comparatively hard PVC is configured at the housing body and may be joined to fuel- tank flap. Advantageously the relatively hard PVC evinces advantageous mechanical properties applicable to said hinge arm as well. The hinge arm may be pivotable and also be made by injection molding.

[13] In another embodiment mode of the present invention, a PVC fuel-tank flap, in particular a relatively hard PVC fuel-tank flap, is configured on the said hinge arm. In the design comprising both hinge arm and fuel-tank flap, the fuel filler housing constitutes a compact module allowing especially simple configuration into the motor- vehicle body.

[14] The present invention is elucidated below in relation to the appended Figure.

[15] This single Fig. 1 is much simplified schematic cross-section of a fuel filler housing inserted into the motor- vehicle body and fitted with fuel-tank neck.

[16] The fuel filler housing consists of a tub-shaped or pot-like housing body 10 made of a comparatively hard PVC. The fuel filler housing is made by two-component injection molding, said body 10 being injection-molded first. Next a first seal 12 sealing off the fuel-tank neck 14 is injection-molded onto the body 10. Preferably the further seal 16 sealing off the motor- vehicle body 18 indicated in the Figure is injection-molded onto the body 10 in the same operational step.

[17] The segment of the motor- vehicle body 18 is part of the vehicle's outer skin. The fuel-tank neck 14 is connected by a fuel conduit to the fuel-tank. Said neck may be sealed for instance by a screw or valve seal not shown in the Figure.

[18] The Figure of the present invention also shows a fuel-tank flap 20 covering the entire fuel filler housing 20. Preferably the fuel-tank flap 20 is pivotably connected by an omitted hinge arm configured at the housing body 10 to said fuel filler housing.

[19] The seal 12 is conical and slants relative to the wall of the fuel-tank neck 14. As a result, in the course of assembly, the fuel filler housing may be very easily slipped onto the said neck 14 and effect very good sealing. Moreover the conical seal 12 is able to absorb vibrations between the vehicle body 18 and the fuel-tank neck 14 and may compensate any manufacturing tolerances without thereby degrading sealing. Again, the seal may assume a complex shape including at least one conical segment.

[20] Further features of the fuel filler housing of the present invention are omitted from the appended Figure, for instance snap-in elements at the housing body to lock said fuel filler housing to the vehicle body or a fuel-tank flap locking mechanism connected to the central locking mechanism.