JPH0122785Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field The present invention relates to a vibration damping device for a floor panel of an automobile, and in particular to a vibration damping device that effectively utilizes a heat insulator in an exhaust pipe. Regarding a shaking device.

〓Prior Art〓 When vibrations are transmitted to the vehicle body from the wheels, engine, or drive system, this causes vibrations and generates noise. Therefore, by preventing such noise from the vehicle body as much as possible, it is possible to reduce the noise inside the vehicle. Especially since the floor panel has a large area,
Easy to cause membrane vibration. When the frequency of the vibration of the floor panel matches the frequency of the cavity resonance inside the car, the inside of the car becomes a resonance box and causes sound resonance, thereby producing muffled sound. This muffled sound is relatively low-frequency noise and is unpleasant, thereby deteriorating the ride comfort inside the vehicle.

In order to reduce the muffled noise caused by the vibration of the floor panel, measures such as attaching the floor panel to the frame via a buffer are taken, but muffled sound cannot always be completely prevented. On the other hand, an exhaust pipe is placed below this floor panel, and a heat insulator is installed between the exhaust pipe and the floor panel to prevent the radiant heat generated by this exhaust pipe from being transmitted to the floor panel. It's starting to become easier. However, conventional heat insulators for automobiles are provided independently of the floor panel, and do not have any function to prevent vibration of the floor panel.

〓Purpose of the invention〓 The present invention was made in view of the above-mentioned problems, and it aims to control the floor panel by effectively utilizing a heat insulator to prevent the transfer of heat generated by the exhaust pipe. It is an object of the present invention to provide a vibration damping device that performs vibration.

〓Structure of the invention〓 According to the present invention, an exhaust pipe is disposed below a floor panel, and a heat insulator is provided between the floor panel and the exhaust pipe, and the heat insulator allows the exhaust gas to be removed from the exhaust pipe. In an automobile configured to prevent heat transfer from a pipe to the floor panel, a weight is added to the heat insulator, and the heat insulator is a buffer having a spring constant that cancels vibrations of the floor panel. This invention relates to a vibration damping device for a floor panel, characterized in that it is mechanically coupled to the floor panel through a body, and the vibration of the floor panel is damped by the heat insulator and the buffer. By damping the vibration of the floor panel using the heat insulator in this manner, muffled noise is prevented.

〓Example〓 The present invention will be described below with reference to an illustrated example.
Figures 1 and 2 show a small truck equipped with a floor panel vibration damping device according to the present embodiment, and an engine 2 is disposed under a bonnet 1 constituting an engine room. There is. An exhaust manifold 3 is connected to a side surface of the engine 2, and the tip side of the exhaust manifold 3 is connected to an exhaust pipe 4. Therefore, exhaust gas from the engine 2 is discharged through the exhaust pipe 4. An exhaust gas purification device 5 and a muffler 6 are connected to the exhaust pipe 4, respectively.The purification device 5 purifies the exhaust gas, and the muffler 6 reduces exhaust noise. There is.

The exhaust pipe 4 is arranged below the floor panel 7 of the cab. As shown in FIGS. 3 and 4, this floor panel 7 is provided with a protrusion 8 at approximately the center in the width direction, and a transmission 9 is provided below this protrusion 8. It is about to be placed. A shift lever 10 of this transmission 9 is projected onto the upper surface of the floor panel 7 through an opening 11 formed in the projection 8. Furthermore, this shift lever 10
The base portion is covered with an elastic cover 12 made of rubber. A heat insulator 13 is attached to the lower side of the floor panel 7, and this insulator 13 prevents particularly radiant heat of the exhaust gas 4 from being transmitted to the floor panel 7. .

Next, the connection structure between the heat insulator 13 and the floor panel 7 will be explained.
As shown in the drawings and FIG. 5, the heat insulator 13 is connected to the floor panel 7 via a mounting rubber 14 and a bracket 15. As shown in FIG. The bracket 15 has a U-shaped cross section and is attached to the lower surface of the floor panel 7 by welding. A mounting rubber 14 is attached to the lower surface of this bracket 15, and this rubber 14 is attached to the bottom of the bracket 1.
A connecting bolt 16 is attached so as to be sandwiched between the heat insulator 5 and the heat insulator 13.

Next, the operation of the vibration damping device for the floor panel 7 having the above configuration will be explained. Particularly, the footrest portion of the floor panel 7 where the pedals and the like are arranged is a flat surface with a relatively wide area in order to improve the comfort of the floor panel and the operability of the pedals. Therefore, such a floor panel 7 lacks rigidity and tends to vibrate, making it a place where it is easy to generate muffled noise inside the vehicle. And the three vibration modes 18, 19, shown in FIG.
20 vibrations are becoming more likely to occur. However, as described above, this floor panel 7 is connected to the heat insulator 13 via the mounting rubber 14, thereby preventing the floor panel 7 from vibrating. .

It is generally known that vibration of a plate-shaped body such as the floor panel 7 can be prevented by attaching a damping material to the plate-shaped body or by bonding a heavy object to the plate-shaped body. Here, the heat insulator 13 constitutes a member for the floor panel 7 to prevent this vibration, and the vibration of the floor panel 7 is damped by the heat insulator 13. Moreover, since the spring constant of the mounting rubber 14 is set to cancel the vibration of the floor panel 7, the vibration of the floor panel 7 is suppressed by the insulator 13, thereby reducing muffled noise in the room. It is starting to be reduced. Incidentally, as shown in FIG. 4, a weight 17 may be added to the heat insulator 13 to more effectively prevent vibration of the floor panel 7.

As described above, according to the truck according to the present embodiment, the floor panel 7 includes the heat insulator 13 for preventing heat transfer from the exhaust pipe 4 to the panel 7, and the heat insulator 13 and the floor panel 7. Vibration is damped by a mounting rubber 14 interposed between the panel 7 and the panel 7. Therefore, this heat insulator 13 can be installed in the panel 7 without providing a new vibration damping mechanism.
By simply connecting the floor panel 7 to the floor panel 7 through the rubber 14 and the bracket 15, vibration of the floor panel 7 can be effectively prevented, thereby making it possible to reduce muffled noise inside the vehicle.

Although the present invention has been described above with reference to an illustrated embodiment,
The present invention is not limited to the above embodiments, and various modifications can be made based on the technical idea of the present invention. For example, the above embodiment relates to a vibration damping device for a floor panel 7 of a small truck, but the present invention is applicable to vibration damping devices for floor panels of various other automobiles.

〓Effects of the invention〓 As described above, in the present invention, the heat insulator is mechanically coupled to the floor panel via the buffer, and the vibration of the floor panel is damped by the heat insulator. It is something. Therefore, it is possible to damp the vibration of the floor panel without adding a new damping mechanism, thereby achieving a reduction in muffled noise inside the vehicle.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a small truck equipped with a vibration damping device according to an embodiment of the present invention, and FIG. 2 is a side view of the same.
Figure 3 is a perspective view showing a part of the floor panel to which the damping device is installed, Figure 4 is a sectional view taken along the line ~ in Figure 3, Figure 5 is an enlarged view of the heat insulator installation part. FIG. In addition, in the symbols used in the drawings, 4...Exhaust pipe, 7...Floor panel, 13...Heat insulator, 14...Mounting rubber, 15
... Bracket, 16 ... Connection bolt.

Claims (1)

[Scope of utility model registration request] An exhaust pipe is disposed below the floor panel, and a heat insulator is provided between the floor panel and the exhaust pipe, and the heat insulator allows heat to be transferred from the exhaust pipe to the floor panel. In an automobile designed to prevent transmission, a weight is added to the heat insulator, and the heat insulator is connected to the floor panel and the machine through a buffer having a spring constant that cancels vibrations of the floor panel. A vibration damping device for a floor panel, characterized in that the heat insulator and the shock absorber are coupled together to damp the vibration of the floor panel.