JPH02179564A - Roof structure for automobile - Google Patents

Abstract

PURPOSE:To absorb the vibration in a car room and reduce the confined sound by connecting the parts between a number of divided basic plates arranged on a same plane by a number of damper members and forming a molded ceiling member covering the undersurface of a roof panel. CONSTITUTION:The ceiling part of a car room is covered by a roof panel and a molded ceiling member 4, etc., arranged under the roof panel. In this case, the molded ceiling member 4 consists of a number of divided basic plates 29-33 arranged on the same plane and a number of damper members 34-37 arranged between the divided basic plates 29-33 and is formed as an integral structure. Each divided basic plate 29-33 is formed from a corrugated cardboard, etc., and each peripheral edge part 38 is formed into a thin part. Each damper member 34-37 is formed into strip form, and each engagement groove 39 into which each peripheral edge part 38 is press-fitted is formed onto the both side surfaces. Therefore, the vibration absorbings effect can be improved by utilizing the damper members 34-37.

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 a car is a roof panel made of iron plate, and the bottom side of the roof panel is a molded base material made of resin or cardboard, which is a single rigid body that runs along the panel surface. A molded ceiling material is installed. Furthermore, the surface of this molded ceiling material is covered with a skin or the like.

[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 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 a roof panel of an automobile, the molded ceiling material being provided with a molded ceiling material. , a plurality of divided substrates arranged on the same surface are connected by damper materials to form a plate shape.

[Function] According to this configuration, since the plurality of divided substrates are connected by the damper material, vibration between the divided substrates is facilitated by the damper material, and vibration of the entire molded ceiling material can be obtained. . Therefore, when vibrations occur inside the vehicle interior due to noise or the like, the entire molded ceiling material vibrates and spreads within the molded ceiling material, and at the same time, this vibration energy is sequentially absorbed by the damper material and the divided substrate. As a result, sound energy at frequencies that could not be absorbed in the past can be well absorbed, reducing muffled noise in the vehicle interior and improving ride comfort.

[Embodiment 1] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an external perspective view showing the roof portion of an automobile to which the present invention is applied, and FIG. 2 is a schematic enlarged sectional view taken along the line ■■ in FIG. 1.

In FIGS. 1 and 2, 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 includes a plurality of divided substrates 29, 30, 31, as shown in detail in FIGS. 3 to 5.
, 32 and 33 on the same surface, and each divided substrate 29
- 33 are connected by damper materials 34, 35, 36, 37, respectively, and are formed as a single roof-shaped piece. More specifically, each of the divided substrates 29 to 33 is made of microwave felt, cardboard, or the like. Additionally, the peripheral portions 38 of the divided substrates 29 to 33 connected by the damper materials 34 to 37 are formed as thin parts. ~37 is formed in a band shape,
Each divided board 29 is provided on both sides of the damper materials 34 to 37.
Engagement grooves 39 into which the peripheral edge portions 38 of ~33 are press-fitted, respectively.
is provided. Then, when connecting the divided substrates 29 to 33, each peripheral edge portion 38 is press-fitted into the engagement groove 39 by applying an adhesive, and this press-fitting engages the damper material 34.
37 and each of the divided substrates 29 to 33 are connected to each other,
A one-piece molded ceiling material 4 having a roof shape is formed. Further, a skin material is attached to the lower surface of the molded ceiling material 4 as required. This skin material is formed into a sheet shape by arranging raised tricot on a nonwoven fabric or a urethane material. Furthermore, in addition to the mounting holes 23 into which the screws 14 are inserted, the molded ceiling material 4 formed in this manner also has through holes and notches (not shown) that escape from the parts where room lamps, interior mirrors, etc. are mounted. etc. will be provided. Note that the damper materials 34 to 37 are made of elastic members such as silicone rubber or soft resin materials, and when vibrations in a relatively low frequency range of about 30 to 200 Hz occur, the damper materials 34 to 37 are It is set to resonate.

When this molded ceiling material 4 is attached to the roof site rail 5, both side portions are first pressed against the inner panel 11 of the roof site rail 5, and then the molded ceiling material 4 is attached to a screw hole (not shown) formed in the inner panel 11. The screw 14 is screwed into the hole 23 to be attached. Further, from this point on, it is received from below by a garnish 10 attached to the roof site rail 5, and the joint between the inner panel 11 and the molded ceiling material 4 is hidden.

The garnish 10 is formed of a resin material in the shape of a rail, and has a bulge portion 12a at the tip of the inner surface that is snap-fitted into an engagement hole (not shown) provided on the inner panel 11 side. A stop pin 12 is integrally provided. 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 placed in contact with the lower surface of the molded ceiling material 4, and is molded from below. Ceiling material 4
While supporting the inner panel 11, the bulging portions 12a are snap-in engaged with the engagement holes on the inner panel 11 side to be attached.

In the automobile roof structure that has been refined in this way, when vibrations occur in the passenger compartment 2 due to engine noise, etc., these vibrations hit the molded ceiling material 4. Then, the molded ceiling material 4 is divided into a plurality of divided substrates 29. Damper material 34-3 between ~33
Since the damper members 34 to 37 are connected to each other and formed as a single piece to form a roof shape, the parts between the divided boards 29 to 33 are likely to vibrate, and the vibrations are active in this part. occurs and resonates. At this time, a part of the vibration energy spreads in a plane within the molded ceiling material 4, and at the same time, this vibration energy is absorbed within the divided substrates 29 to 33 and damper materials 34 to 37, in a way that could not be absorbed conventionally. Even relatively low frequency vibration energy is well absorbed. This eliminates the muffled noise inside the vehicle compartment 2.

Therefore, in the roof structure of this automobile, sound energy in the low frequency range inside the vehicle interior 2, which could not be absorbed by conventional structures, is sequentially absorbed within the molded ceiling material 4, thereby eliminating muffled sound. This can improve ride comfort.

In the above embodiment, a structure in which the divided substrates 29 to 33 are divided into five parts has been described, but this structure can be modified in various ways. It goes without saying that the present invention can be modified in other ways within the scope of its gist.

[Effects of the Invention] As explained above, according to the automobile roof structure according to the present invention, since the plurality of divided substrates are connected by the damper material, the vibration between the divided substrates is suppressed by the damper material. vibration of the entire molded ceiling material. Therefore, when vibrations occur inside the vehicle interior due to noise or the like, the entire molded ceiling material vibrates and spreads within the molded ceiling material, and at the same time, this vibration energy is sequentially absorbed by the damper material and the divided substrate. As a result, sound energy at frequencies that could not be absorbed in the past can be well absorbed, reducing 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 A top view showing the molded ceiling material as a single item, Figure 4 is IV- in Figure 3.
FIG. 5 is an enlarged sectional view of the main part along line IV, and FIG. 5 is an exploded perspective view of the main part shown in FIG. 4. 3... Roof panel 4... Molded ceiling material 29-33... Divided board 34-37... Damper material

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, wherein the molded ceiling material serves as a damper between each of a plurality of divided substrates arranged on the same surface. An automobile roof structure characterized by being formed into a plate shape by connecting pieces of wood.