JPH02179557A - Roof structure for automobile - Google Patents

Abstract

PURPOSE:To efficiently absorb the vibration in a car room and reduce the confined sound by interposing a damper member between a roof panel and a molded ceiling member covering the undersurface of the roof panel and allowing a machine screw to penetrate through these members. 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, an installation hole 4b on the molded ceiling member 4 is arranged in correspondence to a tapped hole 11a on an inner panel 11 side of a roof side rail 5, and after attached onto the roof side rail, 5, etc., an outer peripheral part 4a is installed by an installation machine screw 14. When installation by the machine screw 14 is carried out, a damper member 8 on which a through hole 8a for press-fitting the installation machine screw 14 is drilled is interposed between the molded ceiling 4 and the inner panel 11. In other words, the molded ceiling member 4 is installed onto the roof panel 11 through the damper member 8.

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.

Figure 3 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, has a roof shape that follows the inner surface of the roof panel 30, and the surfaces of the outer peripheral portions 3 and 4a directly abut against the inner panel 35, which is the lower surface of the sight rail 32. Roof panel 3 in the closed state
It is located below 0. From then on, the molded ceiling material 3 is
Mounting screws 39 are commonly screwed into the through holes 34b formed on the 4 sides and fixed. In addition, this outer peripheral portion 3
The part fixed with these mounting screws 39 is attached to the inner panel 35 from the bottom of 4a.
This fixed part 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-in engaged with an engagement hole 35b provided on the inner panel 35 side.
are integrated. In addition, this garnish 36
are arranged along each side of the molded ceiling material 34. Then, at each side part, one side part 36a is connected to the roof site rail 3 through the seaming welt 38.
2 and the other side portion 36b is placed in contact with the lower side of the molded ceiling material 34, the inner panel 35
The bulging portions 37a are snap-in engaged with the side engagement holes 35b, respectively.

[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 of approximately I KHz or higher, it does not have a structure that can effectively absorb low-frequency sounds 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 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 roof structure for an automobile in which a molded ceiling material is disposed to cover the lower surface of a roof panel of an automobile, wherein the roof panel and the Mounting holes are provided in correspondence with the molded ceiling material, and a damper material having through holes corresponding to the mounting holes is arranged between the roof panel and the molded ceiling material, and the molded ceiling material is provided with mounting holes corresponding to each other. The molded ceiling material is attached to the roof panel by screwing a mounting screw from the mounting hole on the material side through the through hole of the damper material to the mounting hole of the roof panel.

[Function] According to this configuration, the molded ceiling material is not fixed with screws when it is in direct contact with the roof panel, but is fixed with a damper material interposed in between, which prevents vibrations caused by noise from inside the vehicle interior. When this vibration occurs, the molded ceiling material vibrates together with the damper material. Vibration energy from the vehicle interior is sequentially absorbed by the vibrations between the molded ceiling material and damper material, and the vibration energy that cannot be absorbed by the molded ceiling material and damper material is transmitted to the roof panel and spread to other parts. At this point, it enters the damper material again and is absorbed. As a result, sound energy at frequencies that could not be absorbed conventionally is well absorbed and eliminated. As a result, muffled noise inside the vehicle is reduced and ride comfort is improved.

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

FIG. 1 is a schematic sectional view taken in the transverse direction of a roof portion of an automobile to which an embodiment of the present invention is applied, and FIG. 2 is an enlarged 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, it is formed as a single piece by using cardboard or the like as a molding base material, and pasting soft urethane foam, vinyl chloride sheet, etc. as the outer skin to form a roof shape that follows the lower surface of the roof panel 3. Further, in the outer circumferential portion of the molded ceiling material 4, screw holes 11a (see FIG. 2), which serve as mounting holes, are provided penetrating the inner panel 11 side of the roof site rail 5 at multiple locations. Mounting hole 4b
There are several. This molded ceiling material 4 is
With the mounting holes 4b arranged correspondingly to the screw holes 11a on the inner panel 11 side, attach the outer peripheral portion 4a to the roof sight rail 5.
and a front roof rail (not shown), which is then attached via mounting screws 14. Further, when the roof sight rail 5 is fixed with the mounting screws 14, the damper material 8 is interposed between the roof sight rail 5 and the inner panel 11. This damper material 8 is made of rubber, lanthanum material, etc., and is formed into a band shape and commonly arranged on a plurality of mounting screws 14, or as a single disc-shaped piece arranged on each mounting screw 14. It is formed as . However, in either case, a through hole 8a into which the mounting screw 14 is press-fitted is provided. This damper material 8 has a relatively low frequency of 30 to 200 Hz, which is muffled inside the passenger compartment 2 due to noise.
It is set in such a way that when vibrations in the low frequency range occur, it resonates with the vibrations and absorbs part of the vibration energy. Although not shown in the figures, the molded ceiling material 4 is provided with through holes and cut-out portions that extend beyond areas where room lamps, interior mirrors, and the like are attached.

Furthermore, 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, an engagement hole 11b is provided in the inner surface of the garnish 10 so as to pass through the inner panel 11 side.
A locking pin 12 is integrally provided with a bulge 12a at its tip that is snap-in engaged with the locking pin 12. The garnish 10 is arranged along each side of the molded ceiling material 4. Moreover, in 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 arranged in contact with the lower surface of the molded ceiling material 4, and in this state, As shown in FIG. 2, the bulging portions 12a are attached by snap-in engagement with the engagement holes 11b on the inner panel 11 side.

In the automobile roof structure configured in this manner, when low-frequency vibrations 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 damper material 8 vibrate, and the vibration inside the vehicle cabin spreads within the damper material 8 and the molded ceiling material 4,
Vibration energy is sequentially absorbed within the damper material 8 and the molded ceiling material 4. In addition, the vibration energy that could not be absorbed by the molded ceiling material 4 and the damper material 8 is transmitted to the roof panel 3 side and spreads, and is re-absorbed by the damper material 8 in other parts.
It enters the side and is absorbed.

Therefore, in the roof structure of this automobile, the molded ceiling material 4, the damper material 8, etc. sequentially absorb sound energy in the low frequency range due to noise vibrations generated inside the passenger compartment 2, which could not be absorbed conventionally, so that muffled sound is prevented. You can eliminate the sound. This can improve ride comfort. Furthermore, when installing the molded ceiling material 4, the mounting screws 14 are temporarily fixed with the damper material 8 beforehand, so that workability during assembly is improved and costs can be reduced.

In addition, in the above embodiment, the structure in which the molded ceiling material 4 is fixed to the inner panel 11 of the side roof rail 5 has been described, but this does not necessarily have to be a structure in which it is directly attached to the side roof rail 5. 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 molded ceiling material is not fixed with screws when it is in direct contact with the roof panel, but the damper material is interposed in between. Since it is fixed, when vibrations due to noise occur inside the vehicle interior, this vibration hits the molded ceiling material, and the molded ceiling material vibrates together with the damper material. Vibration energy from the vehicle interior is sequentially absorbed by the vibrations between the molded ceiling material and damper material, and the vibration energy that cannot be absorbed by the molded ceiling material and damper material is transmitted to the roof panel and spread to other parts. The damper is overthrown again at the part where it is absorbed.

As a result, sound energy at frequencies that could not be absorbed conventionally is well absorbed and eliminated. As a result, muffled noise inside the vehicle is reduced, and ride comfort is improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing an embodiment of the roof portion of an automobile to which the present invention is applied, cut in the horizontal direction, and FIG.
FIG. 3 is an enlarged cross-sectional view of the T portion in the figure, and FIG. 3 is a cross-sectional view showing the main parts of the roof portion of a conventional automobile. 3... Roof panel 4... Molded ceiling material 4a... Mounting hole 8... Damper material 8a... Through hole 11a... Screw hole (mounting hole) 14... Mounting screw

Claims (1)

[Claims] (1) An automobile roof structure in which a molded ceiling material is disposed to cover the lower surface of an automobile roof panel, and mounting holes are provided in correspondence with the roof panel and the molded ceiling material, respectively. At the same time, a damper material having a through hole corresponding to the mounting hole is arranged between the roof panel and the molded ceiling material, and the damper material is passed through the through hole of the damper material from the mounting hole on the molded ceiling material side. A roof structure for an automobile, characterized in that the molded ceiling material is attached to the roof panel by screwing a mounting screw into the mounting hole of the roof panel.