JPH11180339A - Upper structure of car body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the upper structure of a car body which can reduce noise coming into the interior of a car by vibration of a roof trim. SOLUTION: At least more than one bulkheads 1 of which upper surface is closely attached to the outside plate 12 and lower surface is closely attached on the roof trim 10 and which are extended from either one of left or right side roof frame to other side roof frame along the car width direction, exist between a front roof frame 2 and a rear roof frame 3. As the upper space of a car body is divided into narrower independent closed space, a resonance mode is decreased. The decrease of the resonance mode enables to lower the acoustic pressure level of the upper surface of the roof trim 10 to lower the noise level in the interior of the car making the roof trim 10 a transmission route, and the comfortability of the occupants can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an upper structure of a vehicle body in which a roof trim reduces noise radiated into a vehicle interior.

[0002]

2. Description of the Related Art As a conventional upper structure of a vehicle body, for example, as disclosed in Japanese Patent Application Laid-Open No. Hei 7-117571,
In some cases, a material having a sound absorbing effect is used for a part of the roof trim to reduce noise. In some cases, the roof trim itself is formed of a sound absorbing material.

[0003]

However, in the above-described upper structure of the vehicle body, a relatively large space is formed between the outer plate and the roof trim, and the facing roof frames are arranged substantially in parallel. As a result, many resonance modes are generated in the front, rear, left and right directions of the vehicle, and the noise that has entered from the cross-sectional space of the front pillar, the center pillar, the rear pillar, and the noise generated by the vibration of the outer plate are amplified. The amplified noise causes the roof trim to vibrate as a load, and finally enters the vehicle cabin through a path in which the vibration of the roof trim radiates noise, increasing the noise level at the occupant ear position. The effect of the conventional sound-absorbing material set on the roof trim is small with respect to the noise generated when the roof trim vibrates due to the sound pressure received from the upper surface, and there is a problem that a sufficient noise reduction effect cannot be exhibited. .

The present invention has been made by paying attention to such a conventional technique, and provides an upper structure of a vehicle body capable of reducing noise entering a vehicle interior due to vibration of a roof trim.

[0005]

According to the first aspect of the present invention,
Between the front roof frame and the rear roof frame,
The upper surface is disposed in close contact with the outer panel and the lower surface is disposed in close contact with the roof trim, and has at least one partition wall extending from one roof frame to the other roof frame along the vehicle width direction or the front-rear direction.

The invention according to claim 2 has a partition located substantially at the center between the front roof frame and the rear roof frame.

According to a third aspect of the present invention, at least two partitions according to the first aspect are provided between the front roof frame and the rear roof frame, and one of them is substantially at the center between the front roof frame and the rear roof frame. And the other is in a position where the ratio of the distance from the front roof frame or the rear roof frame to the distance from the one partition is approximately 1: 3, respectively.

According to a fourth aspect of the present invention, there is provided a partition wall between the left and right side roof frames, the upper surface being in close contact with the outer panel and the lower surface being in close contact with the roof trim, and extending from the front roof frame to the rear roof frame along the front-back direction. , At least one.

The invention according to claim 5 has a partition wall located substantially at the center between the left and right side roof frames.

According to a sixth aspect of the present invention, at least two partition walls according to the fourth aspect are provided between the left and right side roof frames.
One is located substantially at the center between the left and right side roof frames, and the other is a position where the ratio of the distance from one side roof frame to the distance from the one partition wall is approximately 1: 3, respectively. It is in.

According to a seventh aspect of the present invention, an upper surface is formed from an intersection of the partition wall according to the first aspect and the partition wall according to the fourth aspect to each connecting portion between the front roof frame and the left and right side roof frames. A partition having a lower surface closely attached to the roof trim was provided on the outer plate.

According to an eighth aspect of the present invention, an upper surface is formed from an intersection of the partition wall according to the first aspect and the partition wall according to the fourth aspect to each connecting portion between the rear roof frame and the left and right side roof frames. A partition having a lower surface closely attached to the roof trim was provided on the outer plate.

According to a ninth aspect of the present invention, there is provided a side roof frame which is located on the opposite side from each joint between the front roof frame and the left and right side roof frames and from each joint between the rear roof frame and the left and right side roof frames. A partition wall having an upper surface closely attached to the outer panel and a lower surface closely attached to the roof trim is provided substantially at the center of the.

According to a tenth aspect of the present invention, the partition having the upper surface closely attached to the outer panel and the lower surface closely attached to the roof trim is provided in a polygonal or elliptical shape.

According to the first and fourth aspects of the present invention, since the space above the vehicle body is divided into independent narrower closed spaces by the partition walls, the resonance mode is reduced. Then, by reducing the resonance mode, the sound pressure level on the roof trim upper surface is reduced, and the level of vehicle interior noise using the roof trim as a transmission path can be reduced, thereby improving the comfort of the occupant.

According to the second and fifth aspects of the invention, since the partition wall is set at the center position in the front-rear direction and the vehicle width direction, which always becomes a node of the odd-order mode,
A noise reduction effect can be obtained in a wide frequency range.

According to the third and sixth aspects of the present invention, a greater noise reduction effect is realized by providing a partition having a ratio of 1: 3 also at the node of the fourth-order mode.

According to the seventh to tenth aspects of the present invention, by providing an oblique partition wall, each side of a space partitioned by the partition wall and each roof frame is not parallel to each other, so that resonance occurs. The mode is suppressed.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. In the following embodiments, common portions are denoted by the same reference numerals, and redundant description will be omitted.

FIG. 1 to FIG. 3 are views showing a first embodiment of the present invention. FIG. 1 is a view of a ceiling viewed from a vehicle compartment with a roof trim removed, mainly showing vehicle body parts, and omits a vibration damping material and the like attached to an outer plate. FIG. 2 is a diagram showing a central cross section of the upper part of the vehicle body.

First, the structure will be described. The space above the vehicle body surrounded by the left and right side roof frames 4, the front roof frame 2, the rear roof frame 3, the outer plate 12, and the roof trim 10 is defined as a vehicle. 2 provided in the width direction
Are separated by two partition walls 1.

Both ends of the partition 1 are connected to the left and right side roof frames 4 respectively, the upper surface is arranged in close contact with the outer plate 12, the lower surface is arranged in close contact with the roof trim 10, and a part of the lower surface is further formed by an adhesive layer 11. It is fixed to the roof trim 10. That is, the space above the vehicle body is divided into three spaces by the partition 1. In FIG. 2, 13 is a windshield, 13 is a rear glass, 8 is a reinforce,
Reference numeral 9 denotes an opening.

Next, the operation of the first embodiment will be described. The noise transmitted from the cross-sectional space of the front pillar 5, the center pillar 6, and the rear pillar 7 is transmitted to the vehicle interior in a transmission path,
The sound pressure on the upper surface of the roof trim 10 causes the roof trim 10 to vibrate as a load, and as a result, the vibration of the roof trim 10 passes through a path through which noise radiates into the vehicle cabin and a gap between the roof trim 10 and other trims to be joined. There is a route. In the space above the vehicle, the noise level rises due to a resonance mode that hits the front and rear direction and the left and right direction of the vehicle. Is large. In order to reduce the noise entering the passenger compartment, it is important to suppress the resonance mode and reduce the sound pressure level applied to the upper surface of the roof trim 10. According to the structure of this embodiment, the space surrounded by the left and right side roof frames 4, the front roof frame 2, the rear roof frame 3, the outer panel 12, and the roof trim 10 is an independent narrower closed space. Since the space is divided into spaces, the resonance mode is reduced, the rise in sound pressure in the space is suppressed, and the load applied to the roof trim 10 can be reduced.

FIG. 3 shows an example of the effect of this embodiment. FIG. 3 shows the level of the noise generated at the occupant's ear position when traveling on an asphalt pavement having a relatively large surface roughness at a vehicle speed of 50 km / h by the A characteristic. It can be seen that the structure of this embodiment has an excellent noise reduction effect over a wide frequency range.

FIG. 4 is a diagram showing a second embodiment of the present invention. In the second embodiment, between the left and right side roof frames 4, the upper surface is disposed in close contact with the outer plate 12 and the lower surface is closely attached to the roof trim 10, and extends from the front roof frame 2 to the rear roof frame 3 along the front-rear direction. The two partition walls 15 are provided on both sides of the center line in the vehicle width direction.
The structure of the partition 15 itself is the same as in the first embodiment. The space above the vehicle body is divided into three spaces by the two partition walls 15.

Therefore, also in the second embodiment, the resonance mode is reduced as in the first embodiment, and the same noise reduction effect as in the first embodiment is obtained. In the present embodiment, since the partition wall 15 has a structure crossing the reinforce 8, it is conceivable that if the height of the reinforce 8 is high, the adhesion between the partition wall 15 and the outer plate 12 may be impaired. In such a case, urethane having low rigidity may be used as the partition wall 15. Urethane having low rigidity generally has air permeability and does not form an acoustically rigid boundary, but sufficient noise reduction can be achieved by providing the partition wall 15 near the node of the mode in question. You.

FIGS. 5 and 6 show a third embodiment of the present invention. In the third embodiment, a partition 16 located at the center between the front roof frame 2 and the rear roof frame 3, a partition 17 located between the partition 16 and the front pillar 2, and between the left and right side roof frames 4. And a partition wall 18 located at the center of the frame.

Of the resonance modes generated in the space above the vehicle body, the left and right roof frames 1
0 and a substantially central position of the front roof frame 2 and the rear roof frame 3. In the present embodiment, the partition wall 1 is always located at a position serving as a node of the odd-order mode.
Since the structure is set to 6 and 18, the noise reduction effect can be obtained in a wider frequency range than in the first embodiment or the second embodiment. In the even-order mode, a further noise reduction effect can be expected by adding a partition wall 17 at the position of the node of the mode in question.

FIG. 6 shows an example of the effect of this embodiment. FIG. 6 shows the noise level generated at the occupant's ear position when traveling on an asphalt pavement having a relatively large surface roughness at a vehicle speed of 50 km / h by the A characteristic. It can be seen that the present embodiment has a greater noise reduction effect than the first embodiment.

FIG. 7 is a diagram showing a fourth embodiment of the present invention. The fourth embodiment is substantially the same as the third embodiment, except that the partition 19 is moved slightly before the third embodiment, and the distance (a) from the front pillar 2 to the partition 19 and the partition The ratio of the distance (b) from 19 to the partition 16 is set to be 1: 3.

In the frequency range of the road noise targeted by the present embodiment, the even-order mode in question often becomes the fourth-order mode in the front-rear and left-right directions of the vehicle. In the present embodiment, a greater noise reduction effect is realized by providing the partition wall 19 in the vehicle width direction also at the node of the fourth mode.

FIG. 8 is a diagram showing a fifth embodiment of the present invention. In the fifth embodiment, a partition 20 is added to the structure of the fourth embodiment. And the side roof frame 4
(C) from the partition 20 to the partition 20 and the partition 1 from the partition 20
The ratio to the distance (d) up to 8 is set to 1: 3. In the fifth embodiment, the partition wall 20 is provided also at the position of the node of the fourth-order resonance mode in the vehicle width direction.
A noise reduction effect equal to or greater than that of the embodiment can be obtained.

FIG. 9 is a diagram showing a sixth embodiment of the present invention. In the sixth embodiment, the upper surface extends from the intersection of the partition 16 located at the center in the front-rear direction and the partition 18 located at the center in the vehicle width direction to each of the joints between the front roof frame 2 and the left and right side roof frames 4. A partition 21 whose lower surface is closely attached to the roof trim 10 is provided on the outer plate 12.

The reason why many resonance modes exist in the space above the vehicle body is that the side roof frame 4, the front roof frame 2, and the rear roof frame 3 facing each other are formed substantially in parallel. In the present embodiment, a partition 21 is provided in an oblique direction of the vehicle, and each roof frame 2, 3,.
The resonance mode is suppressed by preventing each side of the space partitioned by 4 and the partition 21 from becoming parallel. still,
Contrary to the sixth embodiment, the upper surface is in close contact with the outer plate 12 and the lower surface is in close contact with the roof trim 10 from the intersection of the partition 16 and the partition 18 to the respective joint portions of the rial roof frame 3 and the left and right side roof frames 4. A disposed partition may be provided.

FIG. 10 is a view showing a seventh embodiment of the present invention. In the seventh embodiment, the respective joints between the front roof frame 2 and the left and right side roof frames 4 and the rear roof frame 3 and the left and right side roof frames 4
And four partition walls 22 each having an upper surface closely attached to the outer trim 12 and a lower surface closely attached to the roof trim 10 from the respective joint portions to the center of the side roof frame 4 located on the opposite sides.
Were each provided.

In this embodiment, the resonance mode is suppressed by providing the partition wall 22 in an oblique direction of the vehicle so that the sides of the space partitioned by the roof frames 2, 3, 4 and the partition wall 22 are not parallel. ing.

FIG. 11 is a diagram showing an eighth embodiment of the present invention. In the eighth embodiment, a space partitioned by elliptical partition walls 23 is formed, and four partition walls 24 extend from the elliptical partition walls 23 to the joints of the roof frames 2, 3, and 4 on four sides of the roof. Is formed.

In this embodiment, the roof frame 2,
By preventing each side of the space partitioned by the partitions 3 and 4 from the partition 23 and each side of the space partitioned by the partition 24 from becoming parallel, an effect of suppressing the resonance mode is obtained. still,
The partition 23 may be polygonal instead of elliptical.

[0039]

According to the first and fourth aspects of the present invention, the space above the vehicle body is divided into independent narrower closed spaces by the partition walls, so that the resonance mode is reduced. Then, by reducing the resonance mode, the sound pressure level on the roof trim upper surface is reduced, and the level of vehicle interior noise using the roof trim as a transmission path can be reduced, thereby improving the comfort of the occupant.

According to the second and fifth aspects of the present invention, since the partition wall is set at the center position in the front-rear direction and the vehicle width direction which always becomes a node of the odd-order mode,
A noise reduction effect can be obtained in a wide frequency range.

According to the third and sixth aspects of the present invention, a greater noise reduction effect is realized by providing a partition having a ratio of 1: 3 also at the node of the fourth-order mode.

According to the seventh to tenth aspects of the present invention, by providing the diagonal partition wall so that each side of the space partitioned by the partition wall and each roof frame is not parallel to each other, resonance is achieved. The mode is suppressed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a structure according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line SA-SA shown in FIG.

FIG. 3 is a graph showing a noise reduction effect of the first embodiment.

FIG. 4 is a diagram showing a structure according to a second embodiment of the present invention.

FIG. 5 is a diagram showing a structure according to a third embodiment of the present invention.

FIG. 6 is a graph showing a noise reduction effect of the third embodiment.

FIG. 7 is a diagram showing a structure according to a fourth embodiment of the present invention.

FIG. 8 is a diagram showing a structure according to a fifth embodiment of the present invention.

FIG. 9 is a view showing a structure according to a sixth embodiment of the present invention.

FIG. 10 is a diagram showing a structure according to a seventh embodiment of the present invention.

FIG. 11 is a diagram showing a structure according to an eighth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Partition 2 Front roof frame 3 Rear roof frame 4 Side roof frame 5 Front pillar 6 Center pillar 7 Rear pillar 8 Reinforce 9 Opening 10 Roof trim 11 Adhesive layer 12 Outer plate 13 Front glass 14 Rear glass 15-24 Partition

Claims (10)

[Claims] 1. A front roof frame and a rear roof frame, an upper surface of which is disposed in close contact with an outer plate and a lower surface thereof which is in close contact with a roof trim, extending from one roof frame to the other roof frame along a vehicle width direction or a front-rear direction. An upper structure of a vehicle body comprising at least one partition wall. 2. The upper structure of a vehicle body according to claim 1, further comprising a partition located substantially at a center between the front roof frame and the rear roof frame. 3. At least two partitions according to claim 1 are provided between the front roof frame and the rear roof frame, one of which is located substantially at the center between the front roof frame and the rear roof frame, and the other is located at the center. The upper structure of a vehicle body according to claim 1, wherein a ratio of a distance from the front roof frame or the rear roof frame to a distance from the one partition wall is approximately 1: 3. 4. At least one partition between the left and right side roof frames, the upper surface of which is in close contact with the outer panel and the lower surface of which is in close contact with the roof trim, and which extends from the front roof frame to the rear roof frame along the front-rear direction. An upper structure of a vehicle body, characterized in that: 5. The upper structure of a vehicle body according to claim 4, further comprising a partition located substantially at the center between the left and right side roof frames. 6. A partition having at least two partition walls according to claim 4 between the left and right side roof frames, one of which is located substantially at the center between the left and right side roof frames, and the other being separated from one of the side roof frames. 5. The upper structure of a vehicle body according to claim 4, wherein the ratio of the distance from the first partition to the distance from the one partition is approximately 1: 3. 7. From the intersection of the partition wall according to claim 1 and the partition wall according to claim 4, from the intersection between the front roof frame and the left and right side roof frames, the upper surface is the outer plate and the lower surface is the roof trim. The upper structure of the vehicle body, which is provided with partition walls closely attached to the vehicle. 8. From the intersection of the partition wall according to claim 1 and the partition wall according to claim 4, from the intersection between the rear roof frame and the left and right side roof frames, the upper surface is an outer plate and the lower surface is a roof trim. The upper structure of the vehicle body, which is provided with partition walls closely attached to the vehicle. 9. An upper surface extending from each joint between the front roof frame and the left and right side roof frames and each joint between the rear roof frame and the left and right side roof frames to substantially the center of the side roof frame located on the opposite side. The upper structure of a vehicle body, wherein a partition wall whose lower surface is closely attached to a roof trim is provided on an outer plate. 10. An upper structure of a vehicle body, wherein a partition having an upper surface closely attached to an outer panel and a lower surface closely attached to a roof trim is provided in a polygonal or elliptical shape.