JPS6014944B2 - Vehicle engine vibration noise prevention device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for preventing or reducing vibration noise in a vehicle, in particular a motor vehicle.

2. Description of the Related Art Conventionally, one of the major factors that hinders the comfort of a vehicle is the vibration and noise of the vehicle.

Vehicle vibration noise is caused by the rotation of the engine or vibrations during driving that are transmitted to the vehicle body and vibrate the walls of the body, resulting in indoor noise. By the way, there are various sound reduction methods that can be used to reduce such vibration noise. Pairing cables have been proposed, but the anti-vibration effects of rubber cushions, insulators, and other anti-vibration materials used in various parts of the vehicle, such as engine mounts, body mounts, and suspension systems, have significantly reduced blueness. It is known that

However, in the past, the sound reduction effect of these vibration isolators simply depended on the sound reduction effect of each vibration isolator. However, none of these proposals is expected to have a sound reduction effect greater than the sum of the vibration isolating materials. Moreover, it is difficult to improve individual vibration isolating materials, and the extensive use of adjacent vibration materials is not desirable from the viewpoint of vehicle maneuverability and stability, and it is actually difficult to improve the sound reduction effect in this area. Met.

By the way, in recent years, there has been a tendency for more importance to be placed on preventing or reducing interior noise in order to improve the comfort of vehicles, and a variety of comprehensive sound reduction measures have been implemented. The present invention aims to improve the sound reduction effect, and the present invention provides an effective vibration noise prevention device that does not depend on the sound reduction effect of each subordinate vibration isolating material.

In other words, since secondary engine mountings generally have a symmetrical mounting structure, engine vibrations are transmitted from the left and right mounts to the body in the same phase, and when these vibrations interfere, the vibrations increase and generate vibration noise. For this reason, the vibrations transmitted from the left and right mounts of the engine mounting are changed in phase with each other, so that even if the vibrations of one of them interfere with the vibrations of the other, the vibrations caused by the interference will be suppressed. Preferably, they should cancel each other out without forcing each other so that they do not become large, and in order to change the mutual phase, the vibration transmission action of the vibration isolating material of the mount requires that a phase lag occurs in the transmitted vibrations. Furthermore, we focused on the fact that this phase delay changes depending on the damping coefficient of the vibration isolating material, the dynamic characteristics such as the spring constant, and the vibration transmission characteristics specific to the mount based on the mounting angle. In a mount that forms a mount, the seat surface of one mount is formed perpendicular to the vertical plane in the width direction of the vehicle and has a predetermined width to the horizontal plane, and the seat surface of the other mount is formed so that it is perpendicular to the vertical plane in the width direction of the vehicle and has a predetermined width to the horizontal plane. The left and right mounts are formed to be perpendicular to the vertical plane of the direction and have a predetermined inclination to the horizontal plane, and the left and right mounts are arranged asymmetrically with respect to the rotational axis of the engine to reduce vibration noise of the vehicle body. It is characterized by reducing or silencing the sound.

EMBODIMENT OF THE INVENTION Hereinafter, an embodiment in which the present invention is applied to an engine mounting for a cab-over type automobile will be described in detail based on the drawings.

Cab-over type vehicles have cab 1 as shown in Figure 1.
The engine 3 is connected to the front of the engine 3 by front mounts 4 and 5 that protrude inward from the left and right side frames 2a and 2b of the chassis 2. A rear mount 6 protruding from the cross member 2c of the chassis 2 connects the rear part of the engine 3 to the rear part of the engine 3.
Vibration-proof support is provided on the chassis 2 by points.

According to the present invention, the left and right front mounts 5 of the engine mounting have an asymmetric structure, and the details of this structure will be explained with reference to FIGS. 3 to 5.

First, as shown in FIGS. 3 and 4, the left front mount 4 is attached to the upper surface of the mount bracket 12, which has one end fixed to the inner surface of the left side frame 2a of the vehicle chassis 2. The seat wings 2a are perpendicular to the vertical plane in the width direction and inclined at lo with respect to the horizontal plane. Attach anti-vibration rubber force 5 to plate amount 3 and 1
4, the mounting plate 39 is bonded to the mounting plate 39, and one mounting plate 3 is bolted to the seat plate 2a of the mount bracket 12 to secure it, and the other mounting plate 14 has both ends attached. One seat neck 6a of the upper bracket 16, which has a seat surface 16ay and a width 6b, is fixed by bolting, and the other seat surface 16b is fixed to the engine 3.

Further, as shown in FIGS. 3 to 5, the right front mount 5 is a mount mounted on the inner surface of the right side frame 2b of the chassis 2 in a configuration that is simply opposite to the mount bracket 12 of the left front mount 4. One end of the bracket 18 is fixed, and a seat surface 18a on the upper surface of the end of the mount bracket 16 has a seat surface 19a in a different direction on both ends]9b
One seat surface 19a of the connecting part village 19 is fixed by bolting, and the other seat surface 19b is perpendicular to the vertical plane in the longitudinal direction of the vehicle and inclined at Q2o with respect to the horizontal plane. Arrange it like this.

Furthermore, on the same machine as in the case of the left mount bracket 4, two parallel mounting plates 20 are placed at a predetermined distance.
A vibration isolating rubber 22 is integrally bonded to the mounting plates 20 and 21 between the mounting plates 21 and 21.

By the way, the component in which the anti-vibration rubber 22 is integrally bonded to the attachment plates 20 and 21 has exactly the same configuration as that of the front mount 4 on the left. One seat surface 23a of the upper bracket 23, which has seat surfaces 23a and 23b formed in opposite directions at both ends, is bolted and fixed to the other mounting plate 2i, and the other mounting plate 2i is fixed with bolts. The surface 23b is fixed to the engine 3.

As mentioned above, in the embodiment, the left and right front mounts in the three-point supported engine mounting are used. The seat surface 12a of the mount bracket turtle 2 of the left front mount 4 and the seat surface 19b of the connecting member 19 of the right front mount 6 are provided along the seat surfaces provided in different directions so that they are substantially perpendicular to each other. Because of this, even if the same anti-vibration rubber is placed in different directions, the left front mount 4 and the right front mount 5 have different anti-vibration rubber parts 5 and 22. Due to the difference in the vibration transmission characteristics in each direction based on the characteristics, the vibration transmission characteristics differ from each other.

Therefore, when the engine 3 is operated, the vibration of the engine 3 is transmitted from the engine mounting to the chassis 2 and to the cab 1 through the cab mounting. Due to the different vibration transmission characteristics of the two, they undergo different vibration changes including phase lag. The vibrations of the engine 3 transmitted from the left front mount 4 to the chassis 2 and the vibrations of the engine 3 transmitted from the right front mount 5 to the chassis 2 are further transmitted from the chassis 2 through the cab mounting to the cab. The vibrations are transmitted to the vehicle wall of the cab 1 and further transmitted to the air inside the cabin, but the vibrations transmitted from the left front mount 4 and the vibrations transmitted from the right front mount 5 are the same. interfere with each other during the transmission path, for example, when vibrating the car wall of the cab 1 or propagating through the air inside the cab 1, and in that case, the different phase delays experienced by the left and right front mounts 4 and 5. Based on this, an appropriate phase difference is created between both vibrations, so that one vibration does not amplify the other vibration, preferably both vibrations act inversely or cancel each other out, and the car wall is improved. As a result of reducing vibrations or air vibrations, the vibration noise inside the vehicle is reduced or eliminated.

As clarified through the examples above, the present invention changes the vibration transmission characteristics of a mount in engine mounting from the vibration transmission characteristics of other mounts in engine mounting, and improves the vibration transmission characteristics between mounts with different vibration transmission characteristics. It creates an appropriate phase difference between the vibrations transmitted from the mount, and when these vibrations interfere, they do not strengthen each other, but preferably work inversely or cancel each other out to reduce the sound, and In the example, 3
Although the application is only explained to the left and right front mounts 4 and 5 in a point-supported engine mounting, it is also applicable between the left and right rear mounts in a four-point-supported engine mounting where the front mounts and rear mounts are two on each side. Based on the need for effective or efficient reduction of engine vibration and noise, such as by applying the appropriate vibration transmission characteristics to all or some of the plurality of mounts of the engine mounting, Settings are made.

As explained above, the present invention is capable of reducing the vibration and noise of a vehicle's engine in engine mountings that form a pair of left and right mounts with respect to the rotational axis of the engine. and at right angles to the horizontal plane and with a predetermined angle to the horizontal plane,
Maun on the other side. The left and right mounts are arranged so as to be asymmetrical with respect to the rotation axis of the engine, with the seat surface of the engine being formed so as to be perpendicular to the vertical plane in the longitudinal direction of the vehicle and having a predetermined inclination with respect to the horizontal plane. The vibrations of each engine transmitted from the mount generate an appropriate phase difference, and when they interfere in the transmission path, even if they interfere based on the mutual phase difference, the vibrations do not increase and preferably cancel each other out. As a result, the sound is reduced or silenced, which further reduces the noise inside the vehicle due to engine vibration, and since it is implemented on the existing engine mounting, it is suitable for application to vehicles. It has the excellent feature of being easy and improving the blue reduction effect using existing mounting.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a side view showing a cab-over type automobile having an engine mounting to which the present invention is applied, and FIG. 2 is an overall plan view of the engine mounting shown in FIG. 1. , FIG. 3 is an A-A ablastic view of FIG. 1,
Figure 4 is an enlarged view of the figure in Figure 3, and Figure 5 is B-B in Figure 4.
It is a figure which shows a part of cross section along a line. 1... Cab, 2... Chassis, 3... Engine,
4, 5...Front mount, 6...Rear mount, 1
5, 22... Anti-vibration rubber. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1. Among the engine mountings of a vehicle in which the engine is vibration-isolated and supported on the chassis using multiple mounts, in a pair of left and right mounts with respect to the engine's rotation axis, the seating surface of one mount is placed on a vertical plane in the width direction of the vehicle. The seat surface of the other mount is formed to be perpendicular to the vertical plane in the longitudinal direction of the vehicle and at a predetermined inclination to the horizontal plane. An engine vibration and noise prevention device for a vehicle, characterized in that the left and right mounts are disposed asymmetrically with respect to the rotation axis of the engine.