JPH02179560A - Roof structure for automobile - Google Patents

Abstract

PURPOSE:To absorb the vibration in a car room and reduce the confined sound by arranging a vibration suppressing member onto the inner surface of a side garnish covering the joint part between a roof panel and a molded ceiling member and closely interposing the vibration-suppressing member between the molded ceiling member. 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, after attaching a vibrationproof member 14 along the outer peripheral edge of the upper surface of the outer peripheral part of the molded ceiling member 4, a space part is formed between the roof panel 3, and then the molded ceiling member 4 is installed. While, a garnish 10 which is formed into rail form from a resin material is arranged on the underside of the molded ceiling member 4. On the inner surface of the garnish 10, an engaging pin 12 having a bulging out part 12a engaged with an engagement hole 11a on an inner panel 11 is installed integrally, and a vibration-suppressing member 8 is attached onto the outer peripheral part of the molded ceiling member 4.

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 width 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.

After that, the through hole 35 on the inner panel 35 side
Attachment screws 39 are commonly screwed into the through holes 34b formed on the molded ceiling material 34 side corresponding to a and fixed. Further, from the lower side of this outer peripheral portion 34a, the portion fixed with these mounting screws 39 is covered with a garnish 36 attached to the inner panel 35, and the seam is hidden from the outside.

The garnish 36 is made of a resin material and is formed into a rail shape. Further, on the inner surface of the garnish 36, a locking pin 37 is provided which has a bulge portion 37a at its tip that is snap-fitted into an engagement hole 35b provided on the inner panel 35 side.
are integrated. At each side part, one side part 36a is brought into contact with the roof site rail 32 via the seaming welt 38, and the molded ceiling material 3
4, the bulge 37a is inserted into the engagement hole 35b on the inner panel 35 side.
are attached by snap-in engagement.

[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 high-frequency sounds above approximately IK)Iz, it does not have a structure that can effectively absorb low-frequency sounds that become muffled sounds. Ta. 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 a molded ceiling material that covers the lower surface of a roof panel of an automobile, and a seam between the molded ceiling material and the loop panel. An automobile roof structure covered with a third garnish attached to a roof panel, wherein a damping material is provided on the inner surface of the third garnish, and the damping material is tightly interposed between the molded ceiling material and the molded ceiling material. It is something.

[Function 1] According to this configuration, the vibration damping material is tightly interposed between the third garnish and the molded ceiling material, so when vibrations due to noise occur inside the passenger compartment, this vibration causes the damping material to be integrated with the damping material. The molded ceiling material vibrates. Vibration energy from the passenger compartment side is sequentially absorbed by the vibrations of the molded ceiling material and the vibration damping material. This technology allows better absorption of sound energy at frequencies that could not be absorbed in the past, eliminating muffled noise inside the vehicle and improving ride comfort.

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

Fig. 1 is an external 11f view of the roof portion of an automobile to which the present invention is applied, Fig. 2rM is a schematic enlarged sectional view taken along the line [G] in Fig. 1, and Fig. 3 is an enlarged sectional view of the T section in Fig. 2. It is a diagram.

1 to 3, a passenger compartment 2 (
The ceiling portion of the roof (see FIG. 2) is covered with a roof panel 3, a molded ceiling material 4 disposed below the roof panel 3, and the like.

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. Furthermore, although not shown in the figures, the molded ceiling material 4 is provided with through holes and cutouts that escape the parts where room lamps, interior mirrors, etc. are attached, so that it forms a roof-shaped piece that follows the lower surface of the roof panel 3. It is formed as a thing. This molded ceiling material 4 has a damping material 14 attached along the outer periphery of the upper surface of the outer peripheral portion 4a, and then
This outer circumferential portion 4a is attached to the roof site rail 5 and the front roof rail (not shown) by closely contacting the damping material 14 with the roof panel 3 with a space 9 formed therebetween.

Further, a garnish 10 is disposed below the molded ceiling material 4 attached to the roof panel 3 side in this manner. This garnish 10 is made of a resin material and is formed into a rail shape. Furthermore, on the inside of this garnish 10,
A locking pin 12 is integrally provided with a bulging portion 12a at its tip that is snap-fitted into an engaging hole 11a provided on the inner panel 11 side. A damping material 8 is attached to the vibration damping material 8, which is brought into contact with the vibration damping material 8. The garnish 10 is disposed along each side of the molded ceiling material 4 with the damping material 8 in close contact with the lower surface of the molded ceiling material 4. In addition, at each side part, one side part 10a is brought into contact with the roof site rail 5 via the seaming welt 13, and the other side part 10b is placed in contact with the lower surface of the molded ceiling material 4 through the dividing material 8. The molded ceiling material 4 is supported from below. Furthermore, in this state, as shown in FIG. 3, the engagement hole 11 on the inner panel 11 side
When the bulge portion 12a is engaged with the bulge portion 12a by snap-in, each garnish L1o is attached to the roof sight rail 5, respectively. The damping material 8 and the damping material 14 are made of rubber, soft resin, or the like, and are relatively low-frequency vibrations of about 30 to 200 Hz that cause noise and muffle the inside of the vehicle compartment 2. When the vibration occurs, it is set so that it can resonate with this vibration and absorb a portion of the vibration energy.

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 molded ceiling material 4 and the damping material 8°14 vibrate, respectively.
The vibrations generated inside the passenger compartment 2 are transmitted to the molded ceiling material 4 and the damping material 8.
, 14, and the vibration energy is sequentially absorbed by these.

Therefore, in the roof structure of this automobile, the molded ceiling material 4 and the damping material 8 absorb sound energy in the low frequency range due to noise vibrations generated inside the passenger compartment 2, which could not be absorbed conventionally.
14 etc., it is possible to eliminate muffled sound. This can improve riding comfort.

In addition, in the above embodiment, a structure in which the damping material 14 was interposed between the roof site rail 5 and the molded ceiling material 4 was disclosed.
If the damping material 8 is interposed between the third garnish 10 and the molded ceiling material 4, it is not necessary. 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 vibration damping material is tightly interposed between the third garnish and the molded ceiling material, so that noise is not caused on the inside of the vehicle. When vibration occurs, the molded ceiling material vibrates together with the damping material. Vibration energy from the passenger compartment side is sequentially absorbed by the vibrations of the molded ceiling material and the vibration damping material. 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.

[Brief explanation of the drawing]

Fig. 1 is an external perspective view showing the roof portion of an automobile to which the present invention is applied, Fig. 2 is a schematic enlarged sectional view taken along the line ■-■ in Fig. 1, and Fig. 31! l is an enlarged cross-sectional view of the T part in Fig. 2,
The figure is a sectional view showing the main parts of the roof portion of a conventional automobile. 3... Roof panel 4... Molded ceiling material 8.14... Allocation material 10... Third garnish

Claims (1)

[Claims] (1) An automobile roof structure comprising a molded ceiling material disposed to cover the lower surface of the automobile roof panel, and a joint between the molded ceiling material and the roof panel covered with a third garnish attached to the roof panel. A roof structure for an automobile, characterized in that a damping material is disposed on an inner surface of the third garnish, and the damping material is closely interposed between the molded ceiling material and the molded ceiling material.