The present invention relates to the technical field of motor vehicle, particularly to a temporary protecting device for use in a motor vehicle. More particularly, it relates to a temporary protecting device for use in SCR (Selective Catalytic Reduction) systems, a filler head of a SCR tank including the same, a method for assembling such a filler head on a motor vehicle, and a method for assembling a car body on a car frame.

Motor vehicles are generally equipped with several tanks, such as fuel tanks for containing gasoline or diesel; additive tanks referred to as SCR tanks for containing urea, other precursors of ammonia, or ammonia solutions for use in SCR systems; or any other additive tanks, for storing engine coolant, fluid for the hydraulic brake control system, screen-wash or else headlight-wash liquid and the like. These tanks are typically provided with a filler head through which the content (i.e. fuel, additive, coolant, etc) can be filled into the tank. In the case of a filler head for SCR tanks, the filler head, together with the SCR tank, is usually first mounted on a car frame (main supporting structure of the motor vehicle), then several parts of a car body will be assembled on the car frame.

During the assembly of the car body on the car frame, parts of the car body near the filler head could collide with it due to a very limited space in this area, particularly because the filler head requires to be available from outside once the assembly is finished, to allow easily filling of the tank later. Due to this limited space, parts may be damaged during the assembly of the motor vehicle, or else the assembly may be particularly complicated.

Hence, the object of the present invention is to facilitate the assembly of a car body on a car frame.

To this end, the present invention provides a temporary protecting device for use in a motor vehicle comprising:

- a closing part configured to obstruct an opening of a filler head for a tank during assembling of the tank on the motor vehicle; and

- an elongated part extending from the closing part, the elongated part comprising a first end fixed to the closing part and a second free end;

wherein the elongated part is configured to allow to manipulate the temporary protecting device so that an assembly of the temporary protecting device and the filler head is movable between a temporary position and a final position,

and wherein the closing part is made of elastomer.

This temporary protecting device, particularly a dust cap for use in a filler head for a tank, is different from a classic one which is typically composed of a closing part configured to obstruct an opening of the filler head. Usually, such a dust cap only acts as a temporary protecting device to obstruct an opening of a filler head of a tank before and during the assembly of the tank on a vehicle (for example, during transportation, storage of the tank) in order to prevent any dust, impurities or contaminants from entering the tank. After the assembling, the dust cap will be removed from the filler head to allow access to the internal volume of the tank. In addition to the usual function of temporary protecting the opening of the filler head, the temporary protecting device has an elongated part in addition to the closing part. By holding and manipulating this elongated part, an operator can move an assembly of the temporary protecting device and the filler head obstructed by the former to a temporary position during the assembly of the car body on the car frame, so that there is more space available for the assembling operations. Thus, when the filler head is in the temporary position, the collision problem mentioned above is reduced. Once the assembling is finished, the operator can move it back to its final position in which the filler head works. Thanks to the elongated part, the filler head is easily movable between a temporary position and a final position without using jigs or specific tools, what is advantageous. Indeed, using jigs or specific tools during the assembly is troublesome and even may present the risks of breaking the parts around the filler head; and furthermore, the fact that car manufacturers have to produce or buy the jigs or specific tools and store them leads to a cost increase. Thus, the temporary protecting device as presented above allows to significantly facilitate operations during the assembly of the car body on the car frame and to reduce costs for car manufacturers.

Moreover, the closing part of a dust cap in the prior art is generally made of plastic, which is cheap and clean (no chippings are likely to fall from it to pollute the tank). The level of tightness between the dust cap and the opening of the filler head achieved with plastic is considered as good enough. Hence, there was no need to replace plastic with elastomer. It is appreciated that the temporary protecting device described above fulfils two functions, namely, protecting the filler head of the tank (for example against any dust, impurities, contaminants or the like) before and during its assembling on a vehicle, and allowing an operator to easily move the filler head to a temporary position during the assembly of the car body on the car frame, while the dust cap in the prior art has a unique protecting function. In order to ensure the second function, it is desirable that the device is difficult (a great detaching force needs to be applied) to remove from the filler head once inserted therein. It is found that this object can be well achieved with flexible materials, particularly elastomer, because a closing part made of such a material can be tightly retained in place

The term "temporary protecting device" is understood to mean a device intended to protect a component of the motor vehicle before the component is put into use on the motor vehicle and intended to be removed then, when it is not needed any more. More precisely, the temporary protecting device protects the filler head before being put into use on the motor vehicle.

The term "obstruct an opening" is understood to mean making it difficult for undesired matters to enter the opening by blocking their path. In other words, the closing part is configured to close the opening of the filler head.

The term "free end of a part" is understood to mean an end of the part that is not permanently attached to something. In other words the terms "a first end fixed to the closing part and a second free end" mean that the first end is permanently fixed to the closing part, whereas the second free end is not permanently fixed to something, but can be temporarily fixed to something.

The term "temporary position" is understood to mean a position in which the object in question stays only for a limited period. In the present case, the terms "the filler head is movable between a temporary position and a final position" mean that the filler head stays in the temporary position only for a limited period, more precisely during assembly of the car body on the car frame. The final position should be understood as the position of the filler head when the motor vehicle is in used. Once the filler head in final position, the temporary protecting device can be removed definitively to allow use of the motor vehicle.

The term "tank" is understood to mean a leak-tight chamber intended for the storage of any fluid, such as a fuel, a fuel additive (such as those required for reducing the combustion temperature of the particles retained on the particulate filters of diesel engines for example), an exhaust gas additive (such as urea, other precursors of ammonia, or ammonia solution in SCR (Selective Catalytic Reduction) systems), an engine coolant, a fluid for the hydraulic brake control system, a screen-wash or headlight- wash liquid, for example. The tank may be made from any suitable material.

The temporary protecting device can further comprise one or more of the following features, taken alone or together:

- The elongated part is also made of elastomer, particularly the same one as the closing part. This will make it easier to produce the device. In particular, it will be possible to integrally form the closing part and the elongated part, for example by injection molding process.

The term "elastomer" means any material, such as natural or synthetic rubber, that is able to resume its original shape when a deforming force is removed.

- The elastomer comprises a material selected from the group consisting of: thermoplastic elastomer and ethylene propylene diene monomer rubber. Good results are obtains with these materials. It will be appreciated that other elastomers may also be used as long as they make the closing part of the device difficult to remove from the filler head. The material "ethylene propylene diene monomer rubber" is also known as "EPDM".

- The elastomer has the following features:

. a Shore A hardness ranging from 40 to 60 degree, preferably from 45 to 55 degree, more preferably from 47 to 53 degree,

. and/or a tensile strength above or equal to 4,8 MPa, preferably above or equal to 5,4 Mpa, more preferably above or equal to 6 MPa,

. and/or an elongation at break above or equal to 280%, preferably above or equal to 315%, more preferably above or equal to 350%.

It is found that elastomers having these features lead to particularly good results. - The temporary protecting device further comprises fixing means for temporarily fixing the assembly of the temporary protecting device and the filler head in the temporary position, the fixing means being provided at the second end of the elongated part. Thanks to the fixing means, the assembly of the temporary protecting device and the filler head can be temporarily fixed in the temporary position, allowing to liberate the hand of the operator holding the elongated part.

- The fixing means are configured to fix the elongated part on an existing component of the motor vehicle. In this way, we can make use of a component existing already on the vehicle (provided for another purpose) to achieve the aforesaid purpose. In other words, there is no need to add a specific component on the vehicle for cooperating with the fixing means of the device.

- The fixing means comprise at least one orifice formed in the second end of the elongated part, preferably three orifices or more. The at least one orifice can cooperate with a protuberance on the vehicle so that the assembly of the temporary protecting device and the filler head can be temporarily fixed in the temporary position. More than one orifices allow to provide a corresponding number of temporary positions, which gives the operator more freedom and allow to use a same design of temporary protecting device for different uses, like a standard temporary protecting device. It is understood that the exact number of the orifice can be adapted as desired.

The term "orifice" preferably means a traversing hole made in the material of the elongated part, for example an aperture, a hole, a slot and the like. It may be of any shape. -Alternatively, the fixing means comprise an annular part connected to the second end of the elongated part.

The term "annular part" means a part that is shaped like a ring which may be of any shape, such as circular, square, rectangle, triangle, diamond.

- The closing part has a cylindrical shape for cooperating with a conic shape of the opening of the filler head. It is known that the opening of the filler head is generally of conic shape. Hence, in the prior art, the closing part of a dust cap is also of conic shape complementary to that of the opening, to make sure that the closing part could be easily inserted into the opening. Here the closing part has a surprising cylindrical shape, which allows to further increase the retention force, and thus the force needed to remove the temporary protecting device from the filler head. In other words, this shape of the closing part is particularly advantageous to fulfil the additional function of the temporary protection device presented here. With such a shape, it is more difficult to lose connection between the device and the filler head when they are fixed in the temporary position.

- The closing part, the elongated part and/or the fixing means are integrally formed. This allows to facilitate the manufacturing of the device and make the device more robust. - Temporary protecting device is configured to obstruct a filler head of a SCR tank. It is understood that the application of the device is not limited to SCR tank, but particularly advantageous for this type whose filler head can be difficult to be reached during assembly of the car body on the car frame.

- The temporary protecting device is a dust cap. It is appreciated that dust cap is just a non-limiting example; any other device having a temporary protecting function is possible.

The present invention also relates to a filler head of a SCR tank comprising a temporary protecting device as described above.

The present invention further relates to a method for assembling a filler head for a tank on a motor vehicle, the filler head having a temporary protecting device as described above, comprising the steps of:

- putting the assembly of the temporary protecting device and the filler head in a temporary position in which an operator can manipulate components of the motor vehicle disposed around the filler head, and

- moving said assembly to a final position in which the filler head is received in a filler head bracket of the motor vehicle.

The present invention further relates to a method for assembling a car body on a car frame on which a filler head as described above is mounted, comprising the steps of:

- putting the assembly of the temporary protecting device and the filler head in a temporary position with the help of the elongated part of the temporary protecting device;

- assembling the car body on the car frame; and

- moving said assembly to a final position in which the filler head is received in a filler head bracket of the motor vehicle. The present invention will be better understood when read with reference to the accompanying figures, given only in illustrative purpose. In the drawings:

- figure 1 is a top view of a temporary protecting device according to an embodiment; - figure 2 is a side cross-sectional view of the device of figure 1 ;

- figure 3 is a perspective view of a filler system for a SCR tank with a temporary protecting device mounted thereon;

- figure 4 is a side view of the filler system of figure 3;

- figure 5 is a top view showing a filler head in a temporary position; and

- figure 6 is a top view showing a filler head in its final position.

Figures 1 and 2 show a temporary protecting device 10 according to an embodiment, in a top view and a side cross-sectional view respectively. In this embodiment, the temporary protecting device 10 is a dust cap for a filler head of a SCR tank of a motor vehicle. It is appreciated that it may be any other device that has a temporary protecting function for a filler head of any tank on a motor vehicle. The dust cap 10 comprises a closing part 12 configured to obstruct an opening of a filler head 30 (see figures 3 to 6) for a tank at least during assembling (preferably also before the assembling) of the tank on the motor vehicle. The dust cap 10 further comprises an elongated part 14 extending from the closing part 12, the elongated part comprising a first end fixed to the closing part 12 and a second free end. The elongated part 14 is configured to allow an operator to manipulate the dust cap so that an assembly of the dust cap 10 and the filler head 30 is movable between a temporary position (see figure 5) and a final position (see figure 6). The temporary position is such that a car body part will not collide with the filler head pre- mounted on a car frame during the assembly of the car body on the car frame. As a result, the risks of damaging or breaking parts of the car body intended to be mounted around the filler head as well as the filler head itself are significantly reduced. Moreover, there is no need to use jigs or specific tools to move the filler head to a temporary position, allowing to facilitate operations during the assembly of the car body on the car frame and to reduce costs for car manufacturers.

It is appreciated that the closing part 12 may be made of any suitable materials, preferably elastomer, such as thermoplastic elastomer (TPE) and ethylene propylene diene monomer rubber (EPDM). Preferably, both the closing part 12 and the elongated part 14 are made of elastomer. It is preferred that the elastomer has the following features:

. a Shore A hardness ranging from 40 to 60 degree, preferably from 45 to 55 degree, more preferably from 47 to 53 degree,

. and/or a tensile strength above or equal to 4,8 MPa, preferably above or equal to 5,4 Mpa, more preferably above or equal to 6 MPa,

. and/or an elongation at break above or equal to 280%, preferably above or equal to 315%, more preferably above or equal to 350%. The inventors found that an EPDM with the following properties particularly gives very good results:

The closing part 12 and the elongated part 14 may be integrally formed, for example by injection molding. Alternatively, they can be separately manufactured and then fixed to each other through any suitable means, such as gluing, welding, bonding and screwing.

As best shown in figure 2, the closing part 12 may have a cylindrical shape. This shape is dimensioned such that the closing part 12 can be tightly retained in the opening, which is usually of conic shape, of the filler head 30 once inserted therein. In other words, a great detaching force needs to be applied on the dust cap in order to remove the cap from the opening.

Preferably, the dust cap 10 may comprise fixing means 16 at the second end of the elongated part 14. In the embodiment of figures 1 and 2, the fixing means 16 include three orifices formed in the second end of the elongated part. It is understood that the orifices could be of any shape and there could be more or less orifices as desired. In a variant, the fixing means comprise an annular part including one or more orifices of any shape connected to the second end of the elongated part 14. The annular part may be integrally formed with the elongated part. Alternatively, it may be manufactured separately and then attached to the second end of the elongated part through any suitable means. During the assembly of the car body on the car frame, the fixing means 16 cooperates with an existing component of the motor vehicle so as to fix the assembly of the dust cap 10 and the filler head 30 in the temporary position (see figure 5). The existing component may be for example a stud 40 on an engine cover. In this case, the stud 40 is inserted in the orifice of the fixing means so that the assembly of the dust cap and the filler head is hanged temporarily on the stud 40. It is understood that the fixing means may comprise a protuberance configured to cooperate with an orifice existing on the motor vehicle for the same purpose.

The text below will explain how the dust cap described above is used with reference to figures 3 to 6.

As best shown in figures 3 and 4, the dust cap 10 is inserted in an opening of the filler head 30 which is mounted on a SCR tank (not shown) when the tank is delivered to car manufacturers. Hence, during the transportation of the tank, the dust cap 10 obstructs the opening so as to prevent any dust, impurities, contaminants and the like from entering the tank.

Car manufacturers will first mount the SCR tank (with the filler head and the dust cap mounted thereon) on a car frame. Then they will assemble car body parts on the car frame. During this assembly, an operator will move the assembly of the dust cap 10 and the filler head 30 to a temporary position (see figure 5) and temporarily fix it in this position by inserting an existing component (e.g. a stud 40 on an engine cover) in an orifice of the fixing means 16 of the dust cap 10. In the temporary position of the filler head, the car body parts will not collide with it and there will be more space available to the operator in this area. As a result, the operator can easily perform assembling operations with the risks of damaging or breaking parts reduced or even eliminated. When the assembly is finished, the operator will move the assembly of the dust cap 10 and the filler head 30 to its final position (see figure 6) in which the filler head 30 is received in a bracket 50. Finally, he will remove the dust cap 10 from the filler head 30 and connect the filler head 30 to a component of the vehicle.

The drawings and the above description describe non-limitative particular embodiments of a temporary protecting device, a filler head including the same or method for assembling such a filler head for a tank on a motor vehicle. Some conventional aspects have been simplified or omitted in teaching the principles. Those skilled in the art should know that the variations from these embodiments fall into the scope of the present invention. It should be appreciated that the above features can be combined in various ways to form a plurality of variations. Thus, the present invention is not limited to the above particular embodiments, but defined by the following claims and their equivalents.