JPH0611393Y2 - Vehicle anti-vibration device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a liquid filled vibration damping device for a vehicle, and more particularly to a liquid filled vibration damping device that can be suitably used for an engine mount.

[Prior Art] FIG. 5 shows an example of a conventional liquid filled engine mount (Japanese Patent Laid-Open No. 60-220239). In the figure, the liquid chambers A and B are divided into partition walls 3 in the engine mount.
The chamber walls 1 and 2 of both liquid chambers A and B support the engine, and the engine mount body is fixed to the vehicle frame by the side walls.

In the center of the partition wall 3, there is provided an empty chamber 31 'which communicates with the liquid chambers A and B, and the inside of the empty chamber 31' is a rubber wall 3 '.
The liquid chambers A and B are partitioned by 2 '. Further, the diaphragm wall 3 is connected to the outer peripheral portion of the partition wall 3 by connecting both liquid chambers A and B.
3'is provided.

The two liquid chambers A and B are also connected by a bypass flow passage 34 'which allows the sealed liquid to flow without resistance, and the bypass flow passage 34' is provided with a valve body 4 for opening and closing the bypass flow passage 34 '.
Then, the valve element 4 is operated by the electromagnetic coil 5.

At the time of idling of the engine, the electromagnetic coil 5 is de-energized (state shown). In this state, both liquid chambers A,
B is made to communicate with each other by a bypass flow path 34 ', and as the chamber walls 1 and 2 are deformed by the vibration input, the sealing liquid flows between the liquid chambers A and B without resistance and the vibration is absorbed.

During normal traveling of the vehicle, the electromagnetic coil 5 is energized and the valve body 4 closes the bypass passage 34 '. When the shake vibration during running is input in this state, the sealing liquid flows between the liquid chambers A and B through the high resistance throttle hole 33 ', and the vibration is damped. In addition, high-frequency small-amplitude vibration during running is
Due to the deformation of the rubber wall 32 ', changes in the internal pressures of the liquid chambers A and B are alleviated, so that the liquid chambers A and B are well absorbed.

There is an anti-vibration device described in Japanese Utility Model Laid-Open No. 60-97440 as a device that achieves the same operation with another structure.

[Problems to be Solved by the Invention] The above-described conventional vibration damping device has excellent performance in that it can effectively prevent transmission of vibrations from the engine in various driving states of the vehicle. Is
A function to reliably prevent displacement of the engine during cranking or running on a rough road to prevent interference with other parts may be required.

In such a case, in addition to the conventional vibration-preventing action at the time of idling and normal traveling, the anti-vibration device is also required to have a vibration-preventing action at the time of cranking or the like.

The present invention has been made in view of the above demands, and an object of the present invention is to provide a liquid-filled anti-vibration device that can effectively prevent the vibration of a vehicle engine in all operating conditions including cranking.

[Means for Solving Problems] The configuration of the present invention will be described with reference to the drawings. The liquid-filled anti-vibration device is installed in a vehicle, and an elastic body that is deformed by vibration input is applied to the chamber wall 1,
It has the 1st and 2nd liquid chambers A and B which are set to 2, and the partition wall 3 which divides these liquid chambers A and B. The partition wall 3 is provided with a first liquid flow port 31 that opens to the first liquid chamber A, opens to the second liquid chamber B, and communicates with the first liquid flow port 31. A second liquid flow port 32 is provided, and a small diameter throttle channel 33 is provided in the partition wall 3, one end of which is opened to the first or second liquid chambers A and B and the other end is throttled. The first valve body 4A and the second liquid flow port 32, which communicate with the liquid flow ports 31 and 32 of the liquid chambers A and B in which the flow path 33 does not open, and open and close the first liquid flow port 31. And a second valve body 4B for opening and closing the first valve body 4A.
A first valve drive means 5A for driving the valve and a second valve drive means 5B for driving the second valve body 4B are provided.

[Operation] In the liquid filled vibration damping device having the above structure, the first and second valve drive means 5A, 5B are used when the engine is idle.
Both valve bodies 4A and 4B are opened. As a result, the sealing liquid flows between both liquid chambers A and B without resistance, both the spring constant and the damping coefficient of the device become small, and the idle vibration of small amplitude is well absorbed.

During normal traveling of the vehicle, the valve drive means 5A, 5B close the valve body 4A of the liquid chamber A in which the throttle channel 33 is opened.
In this state, the two liquid chambers A and B communicate with each other through the throttle channel 33, and the apparatus has a large attenuation coefficient peak in the low frequency region due to the resonance of the liquid present in the throttle channel 33. When a relatively large low-frequency engine shake vibration is input during traveling, this is quickly suppressed by the damping force of the device. Further, the high-frequency small-amplitude vibration in the muffled sound region is well absorbed by the relatively low dynamic spring constant and the sharp decrease of the damping coefficient in this region.

When cranking or traveling on a rough road, the valve bodies 4A and 4B are closed by the valve driving means 5A and 5B. In this state, both liquid chambers A and B are sealed, the dynamic spring constant of the device becomes extremely large, and low frequency large amplitude vibration of the engine due to cranking or the like is suppressed.

[Effect] As described above, according to the vibration isolator of the present invention, it is possible to effectively prevent vibration transmission in any of the three main states of vehicle operation.

[Embodiment] FIGS. 1 and 2 show an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a thick rubber elastic body, which is in the shape of a circular container that opens downward. A metal base 11 is embedded in the center of the top surface of the rubber elastic body 1, and a guide rod 12 is provided below the metal base 11.
Is extended. The bottom surface of the rubber elastic body 1 is joined to the upper surface of the cylindrical side wall 6.

The lower opening of the side wall 6 is closed by the rubber sheet 2 that curves upward and the bottom wall 8, and the rubber elastic body 1 forms a closed space. A liquid chamber is formed by sealing the liquid in the space, and the partition chamber 3 provided in the side wall 6 divides the liquid chamber into an upper and lower main liquid chamber A and a sub liquid chamber B.

The partition wall 3 is a thick ring body (FIG. 2), the outer periphery of which is fixed to the inner periphery of the side wall 6, and the inner peripheral portion has a tapered surface.
A pair of electromagnetic coils 5A and 5B are provided at four locations on the lower surface of the outer peripheral portion of the partition wall 3 at regular intervals, and a throttle channel 33 is provided halfway inside the partition wall 3. Channel 3
Numerals 3 are symmetrical positions in the radial direction, and open on the upper surface and the inner peripheral surface of the partition wall 3, respectively.

Circular valve elements 4A and 4B are provided at upper and lower positions facing the inner opening of the partition wall 3, and the valve elements 4A and 4B are fitted to the guide rod 12 so as to be vertically movable about their centers.

The valve body 4A is a thick body in which the outer periphery of the lower half portion is a tapered surface along the inner peripheral portion of the partition wall 3, and the lower half portion has a case shape and the movable plate 41 is arranged therein. The movable plate 41 is vertically movable within a certain range along the guide rod 12.

Then, liquid circulation ports 42 and 43 penetrating into the case are formed on the upper and lower surfaces of the valve body 4A. The valve body 4A is supported above the partition wall 3 by a coil spring 34 provided between the lower half of the valve body 4A and the inner peripheral portion of the partition wall 3, and the gap between the two serves as a liquid flow port 31. There is.

The valve body 4B is a thick body in which the outer periphery of the upper half portion is a tapered surface along the inner periphery of the partition wall 3, and a seal ring 45 is provided in the fitting portion to the guide rod 12. Liquid circulation ports 44 are provided at a plurality of locations on the outer periphery of the lower half portion of the valve body 4B, and are supported below the partition wall 3 by a coil spring 35 arranged between the upper half portion and the inner periphery of the partition wall 3. ing. The gap between the two is used as the liquid flow port 32.

The spring force of the coil spring 35 is larger than that of the coil spring 34.

The vibration isolator is supported and fixed to the vehicle frame by bolts 81 provided upright on the bottom wall 8, and the engine is fixedly mounted by bolts 71 on the upper plate 7 joined to the top surface of the rubber elastic body 1.

In the vibration isolator having the above structure, the electromagnetic coils 5A and 5B are both non-excited when the engine is idling. In this state, the valve bodies 4A and 4B are both coil springs 3.
It is positioned apart from the partition wall 3 by the spring force of 4, 35 ((1) in FIG. 3), both liquid circulation ports 31, 32 are opened, and the main liquid chamber A and the sub liquid chamber B are directly connected.

When engine vibration is input and the main liquid chamber A is deformed, the seal liquid freely flows between both liquid chambers A and B, so that in the idling vibration region, it is indicated by the region A in FIG. 4 (1). As described above, both the spring constant Kd and the damping coefficient C of the device are small, and effective vibration absorption is achieved.

During normal traveling, the electromagnetic coil 5A is excited. The valve body 4A supported by a comparatively weak spring force is attracted to the partition wall 3 and comes into close contact therewith, and the liquid circulation port 31 is closed (Fig. 3 (2)). In this state, the throttle channel 33 is provided between the liquid chambers A and B.
To communicate via.

Then, in the area of engine shake vibration while running,
As shown in the region B of FIG. 4 (2), the damping coefficient C of the device exhibits a maximum value due to the liquid resonance in the throttle channel 33, and effective vibration suppression is achieved. Further, with respect to the high-frequency vibration in the muffled sound region that is input at this time, the dynamic spring constant Kd and the damping coefficient C that are relatively suppressed by the movable plate 41 that moves so as to reduce the internal pressure change in the main liquid chamber A The reduction allows effective vibration absorption.

When starting the engine or traveling on a rough road, the electromagnetic coil 5B is excited in addition to the electromagnetic coil 5A. This allows
The valve body 4B supported by a relatively strong spring force is also suction-adhered to the partition wall 3 (FIG. 3 (3)), and the liquid flow port 32
And the liquid flow port 44 is closed.

In this state, the main liquid chamber A is hermetically closed, and the internal pressure thereof rises high due to the vibration input, and the dynamic spring constant Kd of the device sharply increases, as shown in region C of FIG. 4 (3), and a relatively large damping coefficient. Together with C, it effectively suppresses large amplitude vibrations such as cranking vibrations.

As described above, according to the vibration isolator of the present invention, the transmission of engine vibration can be satisfactorily prevented in all vehicle driving conditions.

The operating state of the vehicle is determined by referring to signals from a vehicle speed sensor, an engine speed sensor, a vibration pickup, and the like.

In the above embodiment, the vibration isolator having a structure in which only the first liquid chamber is a main liquid chamber having a rubber elastic body as a chamber wall to support the engine has been described. The present invention can also be applied to a device that uses rubber elastic bodies as the chamber walls to deform them complementarily, or a device in which the chamber walls of both liquid chambers are formed of, for example, bellows without supporting force.

It is preferable to use a rare earth metal having a large coercive force for the electromagnetic coil.

The drive means for the valve body is not limited to the electromagnetic coil, and other mechanisms can be adopted.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a vibration isolator showing an embodiment of the present invention, taken along the line I--I of FIG. 2, FIG. 2 is a plan view of a partition wall, and FIG. 3 is a vibration isolator. 4 is a sectional view showing the operation of the main part
FIG. 5 is a frequency characteristic diagram of the dynamic spring constant and damping coefficient of the vibration isolator, and FIG. 5 is a sectional view of the vibration isolator showing a conventional example. DESCRIPTION OF SYMBOLS 1 ... Rubber elastic body (chamber wall) 2 ... Rubber sheet (chamber wall) 3 ... Partition wall 31 ... 1st liquid distribution port 32 ... 2nd liquid distribution port 33 ... Throttling flow path 4A ... 1st valve body 4B Second valve body 5A Electromagnetic coil (first valve driving means) 5B Electromagnetic coil (second valve driving means) A ... Main liquid chamber (first liquid chamber) B ... Sub liquid chamber (second) Liquid chamber)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazumasa Kuze 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Co., Ltd.

Claims (1)

[Scope of utility model registration request] 1. A liquid-filled anti-vibration device which is installed in a vehicle and has first and second liquid chambers having elastic bodies that are deformed by vibration input as chamber walls, and a partition wall for partitioning these liquid chambers. The partition wall is provided with a first liquid flow port opening to the first liquid chamber and a second liquid flow port opening to the second liquid chamber, and these are connected by a communication passage. The partition wall is provided with a small-diameter throttle channel, one end of which is opened to the first or second liquid chamber and the other end of which is opened to the communication passage. The first valve body for opening and closing the distribution port and the second valve body
A second valve body for opening and closing the liquid circulation port of the first valve drive means for driving the first valve body, and a second valve drive means for driving the first valve body.
Second valve drive means for driving the valve body of the first valve is provided, and by the valve drive means, the first valve drive means is used at the time of engine idling.
And the second valve body are both opened to close only the valve body of the liquid flow port of the liquid chamber in which the throttle passage is opened during normal traveling of the vehicle, and the first and the second valves are closed during cranking or traveling on bad roads. A liquid filled vibration damping device for vehicles designed to close both valve elements.