JP3743770B2 - Cab back panel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a back panel of a truck cab, and more particularly to a back panel capable of effectively suppressing membrane vibration of the back panel that causes unpleasant murmurs.
[0002]
[Prior art]
The back panel of a truck cab is structurally formed with a flat surface, and there is a concern that a membrane vibration caused by running vibration or engine vibration may occur, resulting in an unpleasant humming sound. .
[0003]
In order to suppress such vibration of the back panel, conventionally, as seen in, for example, Utility Model Registration No. 2527773, a pair of upper and lower reinforcements along the vehicle width direction fixed to the back panel is connected by a reinforcing member. Alternatively, a plurality of beads along the vertical direction are provided on the flat portion of the back panel to increase the rigidity of the back panel.
[0004]
However, providing the reinforcing member as in the former increases the number of components of the cab and increases the number of man-hours and the weight of the assembly. There was also a need to suppress vibrations of the back panel by attaching a damping material such as an asphalt sheet to the back panel.
[0005]
[Problems to be solved by the invention]
The present invention has been made in view of the above circumstances, and provides a back panel that can effectively suppress vibration that causes a booming noise without using a special reinforcing member or vibration damping material. It is an issue.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, the present invention divides a back panel constituting a rear wall of a cab into a plurality of regions with a reinforcing material fixed to the inner surface of the panel, and the panels in the separated regions are provided. Each region is characterized by bulging backwards along a cubic curved surface with the antinode of the membrane vibration generated in the panel as a vertex. Further, in the invention of claim 2, the glass provided on the back panel and covering the window and the window is formed to bulge backward along a cubic curved surface with the antinode of the membrane vibration generated in the glass as a vertex. It is characterized by.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a rear view of a truck provided with an embodiment of a back panel according to the present invention, and FIG. 2 is a schematic cross-sectional view taken along the line AA of FIG. 2 is provided with a rear window 3.
[0008]
A cross member 5 that crosses the back panel 2 is fixed to the inner surface of the back panel 2 that is coupled to the left and right edges of the rear quarter pillar 4 in the vicinity of the lower edge of the rear window 3. Are fixed to a rear cross member 7 that joins the rear ends of the left and right floor frames 6. The intermediate points of the cross members 5 and 7 are connected to each other via a longitudinal reinforcement 8 fixed to the inner surface of the back panel 2 and the left and right floor frames 6 and the cross member 5 are connected. By fixing the reinforcement 9 along the vertical direction to the inner surface of the back panel 2, the back panel 2 is surrounded by the cross member 5, the rear cross member 7, the reinforcements 8 and 9, and the rear quarter pillar 4 and the rear window. 3 is divided into a plurality of regions on both side portions (see hatched portions in FIG. 1).
[0009]
In each of the regions, the back panel 2 is formed with a smooth curved surface that bulges backward along a cubic curved surface having a peak of the membrane vibration generated in each region. 4. Reinforce with reinforcing members such as cross members 5 and 7 and reinforcements 8 and 9 to increase the rigidity, and by increasing the rigidity of the panel itself by bulging backward in each region, the back panel 2 is suppressed.
[0010]
Further, the glass 10 covering the rear window 3 is also formed of a smooth curved surface that bulges back along a cubic curved surface having the antinode of the membrane vibration as the apex as in the above-described regions, thereby increasing the rigidity of the glass 10. Thus, the vibration of the glass 10 is suppressed and the effect of preventing the booming noise is enhanced while contributing to the improvement of the rigidity of the back panel 2 as a whole.
[0011]
11 is a cab block mechanism attached to the lower center of the back panel 2 reinforced by the reinforcement 8, 12 is a cab mount bracket provided on the rear arch 13, and 14 is a cab mount rubber. It acts as a buffer between the mounting bracket 12.
[0012]
As described above, in the present embodiment, the back panel 2 is reinforced with reinforcing materials such as the rear quarter pillar 4, the cross member 5, the rear cross member 7, the reinforcements 8 and 9 to increase the rigidity of the back panel 2, The back panel 2 is smoothly swelled rearward along a cubic curved surface having the peak of the membrane vibration in each region in each region partitioned by the reinforcing material. For this reason, the rigidity in a specific direction (bead width direction) is not lowered as in the case of a bulging bead due to a quadric surface, for example, and the rigidity of each region is improved in addition to the reinforcing effect by the reinforcing material. The effect acts to increase the rigidity of the back panel 2 and increase the primary resonance frequency of the panel 2.
[0013]
Further, the back panel 2 is divided into a plurality of regions by a reinforcing material fixed to the inner surface of the back panel 3 , and the panels are bulged rearward in each region. For this reason, it is possible to reduce the bulge amount of the panel in each region, to prevent deterioration of the appearance performance of the back panel 2, and to reduce the bulge amount of the back panel 3 as a whole. Therefore, the dimension between the front end of the rear body (not shown) can be easily secured.
[0014]
By the way, the primary resonance frequency of the panel in each region surrounded by the reinforcing material changes depending on the bulging curvature to the rear. Therefore, the primary resonance frequency of the panel in each region surrounded by the reinforcing material can be easily controlled, and the membrane vibration of the panel in the region surrounded by the damping material can be accurately suppressed, and the reinforcement Combined with the reinforcing effect of the material, it is possible to reliably suppress membrane vibration of the back panel, which causes a loud sound.
[0015]
In the embodiment, the glass 10 that covers the rear window 3 is also a smooth curved surface that bulges back along a cubic curved surface with the antinode of vibration generated in the glass as in the case of the panel in each region, For example, since a glass having a cubic surface with a large curvature at the end and a small curvature at the center is used, membrane vibration of the glass 10 is effectively suppressed without causing distortion of the view through the rear window 3. In particular, the primary resonance frequency can be easily controlled by the curvature of the long side of the glass 10.
[0016]
In addition, when the glass 10 having a highly curved cubic surface is attached to the rear window 3 as in the embodiment, a reduction in rigidity caused by providing the rear window 3 on the back panel 2 can be compensated by the glass 10 having high rigidity. For this reason, there is an advantage that the rigidity of the back panel 2 can be further increased to effectively suppress the generation of a booming noise. However, depending on the size of the rear window 3, the glass 9 is not necessarily composed of a cubic curved glass. There is no need to do.
[0017]
Further, in the embodiment, as a concrete example of the reinforcing material, the rear quarter pillar 4, the cross member 5, the rear cross member 7, the attachment portion of the cab block mechanism 11 and the reinforcements 8 and 9 for reinforcing the cab mount portion have a separation function. Although the increase in the number of parts is suppressed, the specific configuration is arbitrary as long as the reinforcing material has a separating function.
[0018]
Furthermore, since the present invention is applied to the back panel of the cab of a tilt cab automobile in the embodiment, the reinforcements 8 and 9 are attached to the three positions of the cab block mechanism 11 and the left and right cab mount positions. The panel 2 is divided into four regions below the rear window 3, and each region and both side regions of the rear window 3 are bulged rearward to increase the rigidity of the back panel 2 and cause a booming noise. Although it is intended to avoid membrane vibration, it is not always necessary to be a cab back panel of a tilt cab car, and it is desirable if it is a flat back panel that constitutes the rear wall of the cab arranged in front of the rear body. The number of regions separated can be arbitrarily set according to the dimensions of the back panel. It is intended that can be, if both sides of the region of the rear window 3 is narrow, for example it may be omitted bulge this portion.
[0019]
【The invention's effect】
As is apparent from the above description, according to the present invention, the back panel of the cab disposed in front of the rear body is reinforced by the reinforcing material fixed to the inner surface of the back panel and the panel is bulged rearward in each region. The rigidity of the back panel can be increased by the synergistic effect of the effect of improving the rigidity of each region, and the primary resonance frequency can be increased. Also, in each region separated by the reinforcing material, the panel is bulged backwards along a cubic curved surface with the antinodes of the membrane vibration generated in each region as a vertex. Compared with the case where it is provided, the panel has higher rigidity, and it is possible to effectively suppress membrane vibration of the back panel, which causes a loud sound without using a vibration damping material. Further, since the bulging amount of the entire back panel is reduced, the dimension between the rear body and the front end can be easily ensured. Furthermore, according to the invention of claim 2, since the reduction in rigidity due to the provision of the rear window on the back panel can be compensated by the glass having high rigidity, the rigidity of the back panel is further increased and There is an advantage that generation can be effectively suppressed.
[Brief description of the drawings]
FIG. 1 is a rear view of a truck provided with an embodiment of a back panel according to the present invention.
FIG. 2 is a schematic cross-sectional view taken along line AA in FIG.
[Explanation of symbols]
1 Cab 2 Back panel 3 Rear window 4 Rear quarter pillar 5 Reinforcement 6 Floor frame 7 Rear cross member 8, 9 Reinforcement 10 Glass 11 Cab lock mechanism 12 Cab mount bracket 13 Rear arch 14 Cab mount rubber

Claims (2)

The back panel (2) constituting the rear wall of the cab (1) arranged in front of the rear body is separated into a plurality of regions by reinforcing members (5) (8) (9) fixed to the inner surface of the panel (2). The back of the cab is characterized in that the panel in each separated area is formed to bulge backward along a cubic curved surface with the antinodes of the membrane vibration generated in the panel in each area as a vertex. panel. The glass (10) covering the rear window (3) provided on the back panel (2) is formed to bulge backward along a cubic curved surface with the antinode of the membrane vibration generated in the glass (10) as a vertex. The cab back panel according to claim 1.

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