JPH02179558A - Roof structure for automobile - Google Patents

Abstract

PURPOSE:To efficiently absorb the vibration in a car room and reduce the confirmed sound by interposing a side garnish consisting of an elastic body between a roof panel and a molded ceiling member covering the underrsurface of the roof panel and securing the damper effect due to elasticity. CONSTITUTION:The ceiling part of a car room is covered by a roof panel 3 and a molded ceiling member 4, etc., arranged under the roof panel 3. In this case, a side garnish 10 which is formed into rail form from an elastic material is arranged on the outer peripheral part 4a of the molded ceiling part 4. An engagement groove 10c into which peripheral edge of the molded ceiling member 4 is press-fitted is formed on one side part 10a of the side garnish 10, and an engagement pin 12 having a building-out part 12 which is snap-in- engaged with an engagement hole 11a on the inner panel 11 of a roof side rail 5 is fixed onto the inner surface. Therefore, the side garnish 10 is interposed between the molded ceiling member 4 and the inner panel 11, and the damper effect due to elasticity can be secured.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automobile roof structure that can reduce muffled noise inside a vehicle interior.

[Prior Art] Generally, the roof of an automobile is made of a roof panel made of a steel plate, and a molded ceiling material made as a single piece along the panel surface is disposed below the roof panel.

FIG. 4 shows an example of the roof structure of a conventional automobile.

In the figure, the left and right sides of the roof panel 30 are fixed via drip channels 31 to outer panels 33, which are the upper surfaces of roof site rails 32 provided on both left and right sides of the roof, and the front and rear are attached to front roof rails (not shown). They are each fixed to the roof rails and are attached to cover the upper part of the passenger compartment.

On the other hand, the molded ceiling material 34 , which is rigid and molded as a single piece into a roof shape along the inner surface of the roof panel 30 , has its outer peripheral portion 34 a in surface contact with the inner panel 35 , which forms the lower surface of the sight rail 32 . , are arranged below the roof panel 30.

Then, the garnish 3 is attached to the lower side of this outer peripheral portion 34a.
Seam 6 is covered and this seam is hidden from the outside.

The garnish 2.36 is made of a hard synthetic resin material and is formed into a rail shape. Further, an engagement hole 35b provided on the inner panel 35 side is provided on the inner surface of the garnish 36.
A locking pin 37 having a bulge portion 37a at its tip that is snap-in engaged with the locking pin 37 is integrally provided. Then, at each side part, one side part 3 is inserted through a seaming welt 38.
6a is brought into contact with the roof sight rail 32, and
With the other side portion 36b placed in direct contact with the lower side of the molded ceiling material 34, the bulge portions 37a are snap-in engaged with the engagement holes 35b on the inner panel 35 side, respectively, and attached.

[Problems to be Solved by the Invention] In an automobile, various noises enter the cabin from the outside. Of these, engine noise is particularly problematic, and this engine noise is generated throughout the drive. Engine noise generally increases with vehicle speed, and at a certain vehicle speed it suddenly increases, sometimes causing a resonance phenomenon accompanied by a muffled feeling. This is what is called vehicle interior cavity resonance, or "muffled sound," and the frequency is low, 30 to 2.
Although the frequency is approximately 0.00 Hz, there was a problem in that the sound was loud and gave an unpleasant feeling, making the ride uncomfortable. Although the conventional roof structure described above can relatively easily absorb sounds in a high frequency range of about IKHz or higher, it does not have a structure that can effectively absorb sounds in a low frequency range that become muffled sounds. For this reason, there has been a desire for a structure that can absorb and remove this muffled sound.

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a structure that can quickly absorb the sound energy that enters the vehicle interior and generate noise, eliminate muffled noise, and improve riding comfort. The purpose of the present invention is to provide a roof structure for an automobile that is made of

[Means for Solving the Problems] In order to achieve the above object, the present invention provides an automobile roof structure in which a molded ceiling material is disposed to cover the lower surface of an automobile roof panel, the roof structure having a molded ceiling material disposed to cover the lower surface of an automobile roof panel. The molded ceiling material is attached to the roof panel via a third garnish having an elastic body interposed therebetween.

[Function] According to this configuration, the third garnish has an elastic body interposed between it and the roof panel, and the molded ceiling material is attached to the roof panel via the third garnish. In other words, an elastic body is effectively interposed between the molded ceiling material and the third garnish, so when vibrations due to noise occur inside the passenger compartment, this vibration causes the elastic body on the third garnish side to The molded ceiling material vibrates as one. Vibration energy from the passenger compartment side is sequentially absorbed by the vibrations between the molded ceiling material and the elastic body. As a result, sound energy at frequencies that could not be absorbed in the past can be well absorbed, eliminating muffled noise in the vehicle interior and improving ride comfort.

[Example] Hereinafter, an example of the present invention will be described in detail using the drawings.

FIG. 1 is a schematic cross-sectional view of the roof portion of an automobile to which the present invention is applied, cut in the transverse direction, and FIG. 2 is an enlarged cross-sectional view of the T section in FIG. 1.

In FIGS. 1 and 2, the ceiling portion of a vehicle interior 2 (see FIG. 1) of an automobile is covered with a roof panel 3 and a molded ceiling material 4 disposed below the roof panel 3. ing.

The roof panel 3 is formed of a steel plate, and its left and right sides are fixed to an outer panel 6, which is the upper surface side of the roof site rail 5, via a drip channel 7, and the front and rear are attached to front roof rails (not shown). They are fixed to the roof rails and the passenger compartment 2.
It is installed with the top covered.

On the other hand, the molded ceiling material 4 is, for example, a resin felt molded product,
Alternatively, a molded base material such as cardboard is used, and soft urethane foam and a vinyl chloride sheet are pasted as the outer skin. In addition, although not shown, through holes and cutouts are provided outside the parts where room lamps, interior mirrors, etc. are attached, and the roof panel 3 is formed as a single piece in the shape of a roof along the lower surface of the roof panel 3. .

A third garnish 10 is disposed on the outer peripheral portion 4a of the molded ceiling material 4.

The third garnish 10 is made of an elastic material such as rubber or soft resin material and is formed into a rail shape. Further, on one side portion 1°a of this third garnish 10, a molded ceiling material 4 is provided.
An engagement groove 10c is provided in which the peripheral edge of the engagement groove 10c is press-fitted and fixed. The peripheral edge of the molded ceiling material 4 is press-fitted into this engagement groove 10c, and the molded ceiling material 4 and the third garnish 10 are integrated. Further, on the inner surface of the third garnish 10, a bulge portion 12a formed at the tip thereof is molded from hard rubber or metal material, and has a bulge portion 12a that snaps into the engagement hole 11a provided on the inner panel 11 side. A locking pin 12 is fixed. The elastic body forming the third garnish 10 is made of rubber, soft resin, etc., and is relatively low-frequency, about 30 to 200 Hz, which is muffled inside the passenger compartment 2 due to noise. When a vibration occurs, it is set in such a way that it can resonate with the vibration and absorb a portion of the vibration energy.

The third garnish 10 is attached along each side of the molded ceiling material 4, and is attached to the roof site rail 5 while being integrated with the molded ceiling material 4. Further, the other side portion 10b of each side is brought into contact with the roof site rail 5 via the seaming welt 13. Furthermore, in this state, as shown in FIG.
2a are snapped into the engagement holes 11a and attached to the roof site rails 5 together with the molded ceiling material 4, respectively. In the molded ceiling material 4 attached to the inner panel 11 in this way, the third garnish 10 itself is formed of an elastic body, so this elastic body is interposed between the inner panel 11 and the molded ceiling material 4. creates a damper effect.

That is, an elastic body is interposed between the inner panel 11 and the molded ceiling material 4.

In the automobile roof structure configured in this manner, when vibrations in a low frequency range occur in the vehicle interior 2 due to engine noise or the like, these vibrations are transmitted to the molded ceiling material 4. Then, the third garnish 10 and the molded ceiling material 4 vibrate integrally, and spread within the molded ceiling material 4 and the third garnish 10, and the vibration energy is sequentially absorbed by them.

Therefore, in the roof structure of this automobile, the molded ceiling material 4 absorbs sound energy in the low frequency range due to noise vibrations generated inside the passenger compartment 2, which could not be absorbed conventionally. Since it is sequentially absorbed by the third garnish 10, muffled sound can be eliminated. This can improve riding comfort.

In addition, in the above embodiment, the entire third garnish 1° is molded with an elastic body, and this third garnish 1
0 is a locking pin 1 made of hard synthetic resin material, metal material, etc.
As shown in FIG. 3, a modification of the present invention is shown in which the entire third garnish 10 is made of a hard synthetic resin material, and the inner surface of the third garnish 10 and the locking pin 12 are fixed. It is also possible to have a structure in which an elastic body 8 is interposed between. In addition, it goes without saying that the present invention is not limited to the above-mentioned embodiments, and can be implemented in various modifications within the scope of the gist thereof.

[Effects of the Invention] As explained above, according to the automobile roof structure according to the present invention, the third garnish has an elastic body interposed between the third garnish and the roof panel, and the molded ceiling material It is attached to the roof panel via. In other words, since the elastic body is effectively interposed between the molded ceiling material and the third garnish, when vibrations due to noise occur inside the passenger compartment, the vibrations cause the elastic body to become integrated with the third garnish side. The molded ceiling material vibrates. Vibration energy from the passenger compartment side is sequentially absorbed by the vibrations between the molded ceiling material and the elastic body. As a result, sound energy at frequencies that could not be absorbed in the past can be well absorbed, eliminating muffled sounds in the vehicle interior. As a result,
Improves ride comfort.

[Brief explanation of the drawing]

Fig. 1 is a schematic cross-sectional view taken in the transverse direction of the roof portion of an automobile to which the present invention is applied, Fig. 2 is an enlarged sectional view of the T section in Fig. 1, and Fig. 3 is a partial cross-sectional view of the same roof portion. FIG. 4 is a cross-sectional view showing the main part of a roof portion of a conventional automobile. 3... Roof panel 4... Molded ceiling material 8... Elastic body 10... Third garnish

Claims (1)

[Claims] (1) An automobile roof structure in which a molded ceiling material is disposed to cover the lower surface of the automobile roof panel, through a third garnish having an elastic body interposed between the roof panel and the roof panel. A roof structure for an automobile, characterized in that the molded ceiling material is attached to the roof panel.