Installation structure for roof rail

The installation structure of a roof rail in which the roof rail is attached to a vehicle inner panel provided underneath a roof panel, through a hole part provided in a roof panel, the installation structure includes: a protruding part which is provided protruding downward from a lower surface of the roof rail, is inserted into the hole part with a gap in-between, and is attached to an upper surface of the vehicle inner panel; and a watertight part which encloses the protruding part, and is flattened between the lower surface of the roof rail and the upper surface of the roof panel, wherein a part of the watertight part extends through the hole part and protrudes beyond the lower surface of the roof panel.

Priority is claimed on Japanese Patent Application No. 2007-319825, filed Dec. 11, 2007, the content of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an installation structure for a roof rail of a vehicle.

2. Description of Related Art

As shown inFIG. 5, some vehicles are provided with a pair of roof rails101at the both sides in the width direction of the roof of a vehicle, in order to carry loads. As shown inFIGS. 6A and 6B, in genera, a particular structure is adopted in which the roof rail101is fastened with bolts at a part where the structural strength is insured, e.g., junction of a roof panel104and a body side panel105.

However, for example, in the structure disclosed in the Japanese Unexamined Patent Application, First Publication H-09-095185, the roof rails are provided at positions away from the junction of a roof panel and body side panels. Instead, at the installation position of the roof rail, a support part is provided. In the structure disclosed in the Japanese Unexamined Patent Application, First Publication 2007-145102, a roof outer panel is directly welded to a roof reinforcing part. The roof rail is provided on the roof reinforce and the roof outer panel.

However, it is desired, from design point of view, to make narrower the junction between the roof panel and the body side panel and also the roof molding, which is fitted at the junction, so that the junction and the roof molding do not visually stand out.

Accordingly, it is necessary to position the roof rail at a position on the roof panel, closer to the vehicle center than the junction. Therefore, it is conceivable to attach the roof rail on a vehicle inner panel provided underneath the roof panel, through a hole part formed in the roof panel.

However, if the distance between the roof panel and the vehicle inner panel is not uniform, it becomes difficult to retain the water-tightness of the hole part formed in the roof panel. In this case, there is a problem in that rainwater leaks into the vehicle interior, and decrease the commercial value of the vehicle. In addition, there is a problem in that, if a load is applied on the roof rail, the relative positional relationship of the roof rail and the hole part formed in the roof panel and the like changes. Therefore, the possibility of the rainwater leakage becomes lager.

In consideration of the above circumstances, an object of the present invention is to provide an installation structure of a roof rail in which the roof rail is attached to the vehicle inner panel provided underneath the roof panel, through a hole part formed in the roof panel, which is capable to maintain water-tightness at the hole part, and to prevent leakage of rainwater and the like into the vehicle interior, even if an alignment error between the roof panel and the vehicle inner panel occurs, or the relative position of the roof rail and the hole part deviates.

SUMMARY OF THE INVENTION

(1) An aspect of the present invention employs the following: an installation structure of a roof rail in which the roof rail is attached to a vehicle inner panel provided underneath a roof panel, through a hole part provided in a roof panel, the installation structure including: a protruding part which is provided protruding downward from a lower surface of the roof rail, is inserted into the hole part with a gap in-between, and is attached to an upper surface of the vehicle inner panel; and a watertight part which encloses the protruding part, and is flattened between the lower surface of the roof rail and the upper surface of the roof panel, wherein a part of the watertight part extends through the hole part and protrudes beyond the lower surface of the roof panel.

According to the installation structure, advantageous effects including the followings can be achieved: even if the alignment precision is not consistent among the roof panel and the vehicle inner panel, or if a load is applied on the roof rail and the relative position of the roof rail and the hole part deviates, the structure can maintain the water-tightness at the hole part, and reliably prevent leakage of rainwater and the like into the vehicle interior.

(2) The installation structure of the roof rail may be constituted as follows: a protruding length of the watertight part is at least 1 mm from the lower surface of the roof panel.

In this case, even if a misalignment between the vehicle inner panel and the roof panel occurs or the relative position of the vehicle inner panel and the roof panel deviates, a part of the watertight part is maintained to be stuffed into the gap between the protruding part of the roof rail and the hole part of the roof panel. Accordingly, the leakage of rainwater through the gap can be reliably prevented.

(3) The installation structure of the roof rail may be constituted as follows: a compression rate of the watertight part is within a first predetermined range; and the length of the contacting part of the watertight part to the roof panel from the fringe of the hole part is within a second predetermined range.

In this case, a) the flattened amount (compression rate) by which the watertight part is flattened between the roof rail and the roof panel, and b) the adhered width (contacting length) of the watertight part to the roof panel from the fringe of the hole part are arranged to reside within a predetermined range. Accordingly, rainwater leakage can be prevented even more reliably.

(4) The installation structure of the roof rail may be constituted as follows: the installation structure further includes a plurality of the protruding parts provided on the roof rail; and the same number of the hole parts as the plurality of the protruding parts provided in the roof panel; wherein each of the protruding parts is provided with the watertight part.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, one embodiment of an installation structure of a roof rail according to the present invention is explained with reference to the figures.

FIG. 1is a perspective view of the installation structure of the roof rail.

A pair of roof rails10is provided on vehicle1such as a passenger automobile along the front-rear direction thereof at the both sides on the roof2.

Each roof rail10includes a pair of leg parts12and a rail part18provided between the leg parts12.

The roof rails10are provided at positions closer to the vehicle center than a pair of roof moldings6. The roof moldings6are inserted into the junction5between the roof panel3and the body side panel4. The roof rails10are provided at positions inside of those junctions5in the vehicle width direction.

FIGS. 2A and 2Bare cross-sections of the installation structure of the roof rail according to the embodiment. InFIGS. 2A and 2B, covers102,103(shown inFIGS. 6A and 6B) provided at an upper surface side of each leg parts12are omitted.

The leg parts12of the roof rail10are provided with a plurality of protruding parts14which extends downward from the lower surface12bof the leg parts12(seeFIGS. 3A and 3B). Each leg part12is provided with two of the protruding parts14, in this embodiment.

The leg parts12are aluminum die casts. The cylindrical protruding part14has a tapered shape with its distal part having a smaller diameter. The tapered shape is formed as a casting draft.

A plurality of hole parts3hare formed on the roof panel3so that the number of the hole parts3hcorresponds to the number of protruding parts14. The inner diameter of the hole parts3his bigger than the outer diameter of the protruding parts14. The plurality of hole parts3hare arranged along the front-rear direction of the vehicle1at positions closer to the roof panel3side (closer to the vehicle center) than the junctions5of the roof panel3and the body side panels4.

The protruding parts14of the leg parts12are each inserted into one of the hole parts3hon the roof panel3, and are fastened by bolts8on the vehicle inner panel7provided underneath the roof panel3. The bolts8are inserted into the bolt holes12hwhich penetrates the protruding part14from the upper surface side of the leg parts12. The bolts make the lower surfaces14bof the protruding parts14contact with the upper surface7aof the vehicle inner panel7. The bolt8and a nut9provided on a lower surface7bof the vehicle inner panel7fasten the leg parts12.

The vehicle inner panel7has a sufficient thickness so as be strong enough to hold the leg parts12.

A ring shaped watertight part30is provided so as to wrap around each protruding part14of the leg parts12. The watertight parts30are flattened between the lower surfaces12bof the leg parts12and the upper surface3aof the roof panel3, when the leg parts12are attached to the vehicle inner panel7. At this time, a part of the watertight part30protrudes out toward the lower surface3bside, from the gap S between the protruding part14of the leg part12and the hole part3hof the roof panel3.

The watertight part30may be made of elastic materials such as polyurethane or rubber. The watertight part30provides air-tightness and water-tightness, by being flattened between parts and by penetrating into narrow gaps.

For the watertight part30materials, Superseat, or Superseal (trade name) may be preferably used. A preferable example of physical properties of the watertight part30is as follows: a density of 0.06 g/cm3; a tensile strength of 1.9 kgf/cm2; a stretch of 140%.

When the watertight part30is arranged at the protruding part14, it is preferable not to use adhesive glue or adhesive tape, in order not to interfere with the deformation of the watertight part30.

Accordingly, the watertight parts30are flattened (compressed) between the lower surfaces12bof the leg parts12and the upper surface3aof the roof panel3, and a part of the watertight part30protrudes out toward the lower surface3bside, from the gap S between the protruding part14of the leg part12and the hole part3hof the roof panel3. By this function, the gap S is sealed, and thereby, rainwater leakage from the hole parts3hof the roof panel3into the interior of the vehicle1is prevented.

A rubber cover20is provided at the outer side of the lower surface12bof the leg part12, in order to conceal the gap between the leg part12and the roof panel3. This cover20also assists to prevent rainwater and/or dust penetration.

FIGS. 3A and 3Bshow one example of an installation and forms of the protruding part14of the leg parts12, hole parts3hof the roof panel3, and the watertight part30.

The vehicle inner panel7and the roof panel3are not directly connected at the vicinity of the roof rail10. Accordingly, due to alignment errors occurred during the production processes, the relative positional relationship of the vehicle inner panel7and the roof panel3deviates among produced vehicles1.

When the vehicle1runs while parcels and the like are loaded on the roof rail10, a large load is applied to the roof rail10from various directions.

Therefore, the position and the attitude of the roof rail10in relation to the roof panel3changes over the time. Accordingly, even if the watertight part30was sealing the gap S, there is a concern that over the time, the water-tightness is compromised and rainwater or the like could penetrate into the vehicle1through the gap S.

According to the installation structure of the roof rail of the present embodiment, since the protruding parts14of the leg parts12and the hole parts3hof the roof panel3and the watertight parts30are constituted as follows, the watertight parts30can reliably maintain the water-tightness and prevent penetration of rainwater and the like into the interior of the vehicle1.

The constitutions and measurements shown below are provided as one example. The present invention is not limited to the constitutions and measurements.

As shown inFIGS. 3A and 3B, for the bolts8which fasten the leg parts12onto the vehicle inner panel7, size M8 bolts with hexagon heads may be preferably used.

In order to make enough margin for the leg parts12to be secured onto the vehicle inner panel7even if the positions of the vehicle inner panel7and the roof panel3varied for each vehicle1due to alignment errors, the vehicle inner panel7is provided with bolt through holes7hhaving a diameter of 9 mm, which is bigger than the diameter of the bolts8. The average diameter of the protruding parts14of the leg parts12is 20 mm.

Accordingly, the diameter of the hole parts3hof the roof panel3is arranged to be 24 mm. This is to design the structure so that a ring shaped gap S is formed between the protruding part14and the hole parts3h, the ring shape having a designed width of 2.5 mm at the maximum, 1.5 mm at the minimum, and an average of 2.0 mm.

In this case, even if the relative positions of the vehicle inner panel7and the roof panel3varied due to the alignment errors, a ring shaped gap S having a width of at least 1.0 mm, at most 2.5 mm is formed (FIG. 3B).

The watertight part30is formed, for example, to have an inner diameter of 19 mm, an outer diameter of 36 mm, and a thickness of 10 mm.

By forming the inner diameter of the watertight part30smaller than the outer diameter of the protruding part14of the leg parts12, the elastic watertight part30can be arranged on the protruding part14without using an adhesive or the like.

The distance between the upper surface3aof the roof panel3and the lower surface12bof the leg parts12is designed to be 2 mm, when these parts are assembled.

Accordingly, the watertight part30attached to the protruding part14of the leg parts12is flattened between the upper surface3aof the roof panel3and the lower surface12bof the leg parts12, until the thickness of the watertight part30becomes 2 mm. Moreover, a part of the watertight part30protrudes from the gap S formed between the protruding part14and the hole parts3htoward the direction from the upper surface3ato the lower surface3b.

As explained above, a gap S having a minimum width of 1.0 mm is formed between the protruding part14and the hole part3h. Accordingly, the gap between the protruding part14and the hole part3his reliably filed with the watertight part30. Therefore, rainwater penetration from the gap S can be reliably prevented.

The relative positions of the vehicle inner panel7and the roof panel3vary because of the alignment errors of the vehicle inner panel7and the roof panel3, and the load applied onto the roof rail10. Namely, the distance between the upper surface3aof the roof panel3and the lower surface12bof the leg parts12varies or changes. Therefore, the amount by which the watertight part30is flattened (compression rate) varies or changes. In this case, the seal of the gap S by a part of watertight part30can not be readily maintained constant, and there is a concern that rainwater or the like may penetrate through the gap S in the conventional structures.

Accordingly, the installation structure is arranged so that the protrusion amount L1of the roof panel3to the side of the lower surface3b(protrusion amount from the lower surface3b) is at least equal or longer than a predetermined amount (length), even when the alignment error reaches the maximum possible amount. Particularly, the structure is arranged so that the watertight part30extrudes (protrudes) from the lower surface3bof the roof panel3by, for example, 1 mm.

In this case, even when the alignment error or position change between the protruding part14of the roof rail10and the hole parts3hof the roof panel3occur, the gap S of the protruding part14and the hole parts3his always filed with a part of the watertight part30. Accordingly, leakage of rainwater or the like from the gap S can reliably prevented.

In order to ensure the protrusion of the watertight part30from the gap S, the ratio by which the watertight part30is flattened (compression rate) is an important factor. In addition, in reliably preventing rainwater leakage from the gap S, the contact length of the watertight part30and the roof panel3(the length of the contacting part measured from the fringe of the hole part3hon the roof panel3) is an important factor, since the contact between the watertight part30and the roof panel3is positioned at an entrance of the leakage path.

Accordingly, a series of experiments are conducted to clarify the relationship of the contact length and the waterproof efficiency, in order to determine a configuration having a reliable waterproof efficiency.

The compression rate of the watertight part30is defined as a flattened amount (thickness) relative to the initial thickness. For example, in this embodiment, the initial thickness of the watertight part30is 10 mm, and the thickness after the flattening is 2 mm, i.e., the flattened amount is 8 mm. Accordingly, the compression rate is 80% (theoretical value).

The contact length of the watertight part30is the length of the contacting part measured from the fringe of the hole part3h, as indicated L2inFIGS. 3A and 3B. In this particular embodiment, the contact length is 6 mm (theoretical value).

FIG. 4is a diagram showing profile conditions of the watertight part.

If an installation structure of a roof rail is configured according to a condition represented by region A ofFIG. 4, rainwater penetrations occur.

If an installation structure of a roof rail is configured according to a condition represented by region B ofFIG. 4, although rainwater penetration can be prevented, if, for example, a repetitive load are applied on the roof rail10, there is a concern of rainwater leakage.

If an installation structure of a roof rail is configured according to a condition represented by region C ofFIG. 4, rainwater leakage from gap S can be reliably prevented.

Under a condition represented by region A ofFIG. 4, both of the flattened rate (compression rate) and the contact length of the watertight part30are not sufficient. Accordingly, a rainwater leakage from the gap S can occur.

It is preferable to use a larger value for either the compression rate or the contact length of the watertight part30. It is even more preferable to use larger values for both of them, so that the profile conditions of the installation structure resides in the region C ofFIG. 4. In this case, rainwater leakage through the gap S can be completely prevented.

By configuring the watertight part30so that the profile conditions are within the region C, even if both of the compression rate and the contact length fluctuated as a result of a misalignment of the vehicle inner panel7and the roof panel3, the rainwater leakage through the gap S can be reliably prevented.

For example, in the case of the watertight part30of the present embodiment, even when the original compression rate of 80% (theoretical value) fluctuated by approximately ±15%, and the original contact length of 6 mm (theoretical value) fluctuated by approximately ±0.5 mm, the profile conditions of the watertight part30would always be within the region B or C (see the circle drawn with a broken line inFIG. 4).

When the profile conditions of the watertight part30reside in region C, it is preferable to use a compression rate as small as possible within the region C. If the compression rate becomes 95% or lager, there is a concern that the roof panel3suffers an elastic strain. In particular, when a material other than above-described Superseat or Superseal (trade name) is used, the condition should be appropriately considered.

On the other hand, the contact length of the watertight part30should be smaller than the width of the leg parts12. This is because otherwise the installation of the cover20would be hindered.

As described above, according to the installation structure of the roof rail of the present invention, when a roof rail10is attached to a vehicle inner panel7provided underneath the roof panel3, through a hole parts3hformed in the roof panel3of the vehicle1, even when there are alignment fluctuations of the roof panel3and the vehicle inner panel7, rainwater leakage can be reliably prevented.

In particular, even when the positional relationship of the protruding part14of the roof rail10and the hole part3hof the roof panel3varied or changed, the gap S between the protruding part14of the roof rail10and the hole part3hof the roof panel3is maintained to be filled with a part of the watertight part30. Therefore, rainwater penetration through the gap S can be reliably prevented.

The flattened amount (compression rate) of the watertight part30between the roof rail10and the roof panel3, and the contact length of the watertight part30and the roof panel3is configured to reside within a predetermined range. Accordingly, the rainwater penetration through the gap S can be prevented even further reliably.

In the embodiment described above, the profiles, materials, and combinations of each component are presented as one example, and various modifications can be made according to the design requirements and the like, without departing from the spirit or scope of the present invention.

For example, in the above embodiment, the protruding part14of the roof rail10and the hole part3hof the roof panel3have a circular shape in plan view. However, the present invention is not limited to the case. These shapes in plan view can either be eclipses or rectangles. In these cases, the planer shape of the watertight part30should also be modified according to the shapes of the protruding part14and the hole part3h.

In addition, the numbers of the protruding parts14formed on the roof rail10may be different among the leg parts12in the front or rear parts of the roof rail10. For example, the leg parts12in the front part may have two protruding parts14, while the leg parts12in the rear part may have three protruding parts14. Furthermore, each profile of the protruding parts14(hole parts3h, watertight part30) may vary from each other.