JPS59186783A - Cab mounting structure for automobile - Google Patents

Abstract

PURPOSE:To improve the feeling of ride and reduce a noise, by providing a compression-type mounting rubber at the front part of the body of an autotruck and a shearing-type mounting rubber at the front and rear parts of a cab floor, in a cab mounting structure for the autotruck. CONSTITUTION:A hood-type autotruck has a hood 1 and a cab 2 on the front part of the vehicle body and a box 3 adjacent to the back of the cab. The hood 1 and the cab 2 are attached to a body frame 4 by a mount 5A at the front part of the vehicle body, a mount 5B at the front part of a cab floor and a mount 5C at the rear part of the cab floor. The box 3 is attached to the vehicle body by a rear mount. Elastic members 12, 13, the cab floor 10 and a body frame 11 are clamped to each other by bolts 16 and nuts 17 so that a compression-type mounting unit is constituted. An annular elastic member 22 is interposed between a cab floor 20 and a body frame 21 so that a shearing-type mounting unit is constituted.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mount structure for attaching the body of a bonnet type truck to a body frame, and in particular to an automobile cab mount structure for attaching the body to the frame at three locations: the front of the vehicle and the front and rear of the cabin floor. °°
It is about improvement.

In automobiles, to improve ride comfort and interior noise,
In order to prevent vibrations from the vehicle frame from being transmitted to the cabin as much as possible, it is desirable to use mount rubber with particularly high vibration absorption capacity for the mounts around the cabin. Conventionally, compression type mount rubber was used for mounts in this area. (Utility Model Publication No. 56-39374), shear type mount structure (-)
No. 6-29289) are known, but all of them have advantages and disadvantages, and are not satisfactory for one minute.

In other words, compression type mount rails are strong against vibrations in the front, rear, left and right directions, but do not have sufficient absorption capacity for vibrations in the vertical direction. On the other hand, shear type mount rubber absorbs vibrations well in the vertical direction, but is weak in the horizontal direction, and is unable to adequately control the vibration amplitude even in the vertical direction against low frequency vibrations. Therefore, if a shear type mount rubber is used, the support of the cabin will become unstable, and although the noise inside the car will be reduced, the cabin will become unstable and the ride quality will be poor. Interference may occur between the two, resulting in problems.

In view of the above-mentioned circumstances, the present invention effectively reduces the transmission of vibration from the vehicle body frame to the cabin, significantly reduces the level of noise inside the vehicle, improves ride comfort (and also eliminates sway in the cabin). The object of the present invention is to provide a structure of a cab mount I for a bonnet type truck that realizes stable riding comfort.

The cab mount structure of the present invention uses compression type mount rubber for the mount device that attaches the front part of the vehicle body to the body frame, and uses shear type mount rubber for the mount device that attaches the front and rear parts of the cabin floor to the body frame. It is characterized by:

In other words, shear tibe mounts with high vibration insulation properties are used for the front and rear gear bin mounts, which have a high contribution to in-vehicle noise and ride comfort, and the mounts at the front of the car body, which have a relatively low contribution, are used to reduce vibrations at low cost. The highly effective compression type -t mount is used to reduce special effects such as wobbling caused by excessive relative displacement between the vehicle body frame and the cabin.

Hereinafter, the present invention will be explained in more detail with reference to the drawings.

Figure 1 is a side view, not showing an example of a bonnet type truck.
FIG. 2 is a plan view thereof, and FIG. 3 is a perspective view showing only the frame. The body of this type of truck has a bonnet section 1 and a cabin 2 at the front, followed by a box 3.
is adjacent. These are attached to the vehicle body frame 4, including a first mount (front cab mount) 5A (front cab mount) at the front of the vehicle body, a second mount 5B (intermediate cab mount) at the front of the cabin floor, and a third mount 5C (front cab mount) at the rear of the cabin floor.
The front part can be accessed via the rear cab mount), and the box 3 can be accessed through other rear mounts (not shown).
can be investigated.

The effect of these mounts on vibration absorption differs somewhat depending on their position, and by using the appropriate type of mount rubber depending on the mount position, it is possible to effectively reduce interior noise and improve ride comfort.

4th A, 4th B, 4th. Figure C shows the sound pressure inside the cabin when vibration is applied to the frame side of the cab mount ((
Figure 4A is a graph showing the results of measuring the vibration frequency (H2) by changing the vibration frequency (H2).
Figure B shows the second maw.

Figure 4C shows the measurement results for the third mount 5C. In each graph, the solid line shows the 6111 results when a single-point type mount rubber is used, and the broken line shows the 6111 results when a compression type mount rubber is used.

As can be seen from these measurement results, the degree of reduction in cabin noise when changing the cab mount from the compression type (dashed line) to the shear type (solid line) is
4B) is the largest, followed by the third mount) 5C (FIG. 4C), and the first mount 5A (FIG. 4A) shows almost no difference. Quantitatively, the first
There is almost no difference in mount.

Furthermore, Fig. 5 shows the results of measuring the longitudinal vibration of the cabin floor on a public road. In Figure 5, the horizontal axis is the frequency (H,
The vertical axis shows the power torque density of vibration (P, S, D,
)(g2/H□), and the solid line represents the first to
When all three mounts are made of shear type mount rubber, the broken line shows the case where all mounts are made of compression type mount rubber. According to this, 20-50I1. y
where the shear type is the compression type], / 1.0
It can be seen that the vibration is suppressed to about 0.

These measurement results show that the shear type mount rubber has a large vibration absorption effect, especially at the second and third mount positions. However, when these shear type mount rubbers are installed at these two locations, the relative displacement between the vehicle body frame and the vehicle body in the vertical, longitudinal, and horizontal directions becomes large, causing the cabin to wobble (feeling unsteady), and the cabin 2 and box 3 The problem arises that interference may occur.

Therefore, in the present invention, a compression-type mount rubber that is inexpensive and has a large vibration control effect is used for the mount, which has little effect on vibration transmission, to improve riding comfort.
Overall, the cab mount has a large vibration absorption effect and effectively suppresses interior noise.

Next, each type of mouse/device will be explained in detail with reference to the drawings.

FIG. 6 shows a compression type mounting device.

1-This is commonly called a skewer type, and there is a through hole 1 in the center between the cabin floor 10 and the vehicle body frame 11.
．． An elastic body 12 having a diameter of 2A is sandwiched between the body frame 11, and an elastic body 13 having a hole 1.3A is provided in the center of another elastic body 12 on the opposite side of the elastic body 12, and these two Elastic body] 2.13 and gear bin floor 1
10 (consisting of two materials in the figure) and vehicle body frame L/- frame 1
1 and upper and lower parts are tightened with bolts 6 and 17 through washers 1.4 and 1.5. The relative displacement (vibration) between the cabin and the frame in the upper F direction is gradually reduced and absorbed by the compressive deformation of the elastic bodies 2, 13 in the axial direction of the bolt 16. Further, the relative displacement in the horizontal direction is caused by the bolt 16 being caused by the relatively large opening 1 of the frame 11.
．． 1A, and is buffered and absorbed by the deformation of the elastic bodies 12 and 13.

FIG. 7 shows a shear type mounting device. This has a shear type elastic body 22 interposed between the cabin floor 20 and the vehicle body frame 2J.
An outer rubber retaining ring 23 is fixed to the upper surface of the frame 21 under the upper bracket 20A fixed to the lower surface of the
An annular elastic body 22 in which 2A is embedded, and an inner rubber retaining ring 24 extending upward from the inner surface of the elastic body 22 are disposed, and further protrudes downward and outward from an opening 21A provided in the frame 21. Elastic body for rebound soba 25
A lower bracket 26 having a
It is tightened by a pair of oaks (27A, 27B) and a stud 28.

1 play l-22 buried in the annular elastic body 22
A is made of a steel pipe with high rigidity, and has the effect of increasing the spring constant against lateral vibration. In other words, when the vibration becomes large in the lateral direction, it acts as a stopper,
Slowly increase the spring constant.

Further, there is a slight gap 22a above and below the annular elastic body 22.
, 221) are formed so that the deformation of the elastic body of the shear tie becomes a compression type when the vertical vibration becomes large to a certain extent. As a result, the spring constant of this mount rubber becomes larger in the downward direction as well. In this case, the change will not be sudden (it will change slowly and will not result in a smooth increase in the spring constant).

As a result, when the amplitude is small, a small spring constant absorbs soft vibrations in both the downward and horizontal directions, and as the amplitude increases, the spring constant is increased to stabilize the vibration. It provides elastic support and can be mounted to provide a comfortable ride and reduce interior noise.

During rebound, the rebound stopper elastic body 25 comes into contact with the lower surface of the vehicle body frame 21 and acts as a soft stopper, thereby regulating vertical vibration [1].

Compression type and shear type mount rubbers as described above are used for the first mount 5A at the front of the vehicle body, the second mount 5B at the front of the cabin floor, and the third mount 5C at the rear of the cabin floor, respectively, as described above. By using this method, it is possible to improve riding comfort and effectively reduce interior noise, making it possible to realize a quiet bonnet-type truck with less vibration.

[Brief explanation of the drawing]

Fig. 1 is a side view showing an example of a bonnet type trunk adopting the cab mount structure of the present invention, Fig. 2 is a plan view thereof, Fig. 3 is a perspective view showing only the vehicle body frame, and Fig. 4A is a vehicle body frame. Figure 4B is a graph showing the relationship between the frequency of imaging applied to the camera and the sound pressure generated in the cabin, and shows a comparison of the mounts at the front of the vehicle body. Figure 4C also shows a comparison of the mounts at the rear of the cabin floor, Figure 5 is a graph showing the results of measuring the front and back of the cabin floor on a general road, and Figure 6 is used for the cab mount structure of the present invention. FIG. 7 is a sectional view showing a compression type mount rubber, and FIG. 7 is a sectional view showing a shear type mount rubber. 1...Bonnet 2...Cabin 3...Box 4...Vehicle frame 5A...Front body mount ( 1st
Mount) 5B...Cabin floor front mount (second mount) 5C...Cabin floor rear mount (third mount) 10.20...Cabin floor 11.2]...Vehicle frame 12.13 Elastic body 22 --- Annular elastic body 22A --- Embedded plate 23 --- Outer rubber retaining ring 24 --- Inner rubber retaining ring 25 ---
・・・・Elastic body for Ribau X dost buckwheat Fig. 1 Fig. 2 Fig. 3

Claims (1)

[Claims] In an automobile cab mount structure in which the front part of the vehicle body and the front and rear parts of the cabin floor of a bonnet type truck can be attached to the vehicle body frame via a mounting device, , uses a compression type mount rubber that compressively deforms in response to the vertical vibration of the vehicle body, and uses a shear type mount rubber that shear deforms in response to the vertical vibration of the vehicle body for the front and rear mounting devices of the cabin floor. An automobile cab mount structure characterized by: