JPH0799188B2 - Power unit mounting device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting device for mounting a power unit such as an engine on a base such as a vehicle body and suppressing the vibration of the power unit from being transmitted to the base. ,
In particular, it relates to an improvement of a so-called fluid-filled type in which a damping effect is obtained by the internal fluid.

(Prior Art) Conventionally, in this type of fluid-filled mounting device, an in-vehicle engine as a power unit moves vertically due to, for example, vibration from the road surface of the vehicle or unbalance of wheels.
It is generally well known as an effect that can effectively reduce the transmission of the vibration to the vehicle body as a base during so-called engine shake that vibrates at about 10 to 15 Hz. That is, this mounting device is, for example, as shown in Japanese Utility Model Laid-Open No. 59-108841 or the like, a vehicle body mounting member mounted on a vehicle body, an engine mounting member mounted on an engine, and provided between the both mounting members, A hermetically sealed fluid chamber that encloses an incompressible fluid, an elastic film that forms a part of the wall of the fluid chamber and is deformed according to a pressure change in the fluid chamber, and the elastic film inside the fluid chamber. And a partition wall having an orifice, which is arranged so as to define a chamber having a wall as a wall, and suppresses engine shake by a vibration damping action (damping action) associated with the resonance phenomenon of fluid at the orifice. It is the one.

(Problems to be Solved by the Invention) In order to further improve such a fluid-filled mounting device, a mass member having a predetermined weight is provided between the engine mounting member and the vehicle body mounting member as an elastic member. The mass member is elastically supported via the, and the resonance frequency of this mass member is set higher than the resonance frequency of the fluid at the orifice, so that the mass member reverses vibration in a frequency range higher than the resonance frequency. Utilizing the phenomenon of oscillating in phase, in addition to the original effect of the fluid-filled mounting device (damping effect for engine shake, etc.), engine combustion noise and gear noise higher than the resonance frequency of the mass member were included. A muffled sound 80 ~
It is conceivable to reduce the high frequency vibration of 100Hz or more to obtain the low pass filter effect.

However, in that case, since the resonance phenomenon of the mass member is used, there arises a problem that the amplitude of vibration sharply increases in the resonance frequency range of the mass member and the vibration transmissibility to the vehicle body extremely increases.

Therefore, the present invention has been made in view of these points,
The purpose is to pay attention to the fact that the above-mentioned orifice becomes clogged in the vibration frequency range higher than the resonance frequency of the fluid inside it, and effectively utilize the pressure rise of the fluid chamber due to the clogging. By suppressing the large amplitude vibration in the resonance frequency range of the mass member,
Damping effect due to the resonance phenomenon of the fluid at the orifice of the fluid-filled mounting device suppresses vibration of the power unit at a predetermined frequency, such as engine shake, and also suppresses the vibration transmissibility of the mass member in the resonance frequency range to achieve its low-pass filter effect To try to utilize.

(Means for Solving the Problem) In order to achieve this object, a solution means of the present invention is a base mounting member mounted on a base such as a vehicle body, a power unit mounting member mounted on a power unit such as an engine, A fluid chamber which is provided between both of the mounting members and is hermetically formed by an elastic body that encloses an incompressible fluid so that the volume can be changed, and a part of the wall of the fluid chamber. A fluid-filled mounting device having an elastic film that deforms in accordance with the change in pressure, the first elastic member provided between the power unit mounting member and the base mounting member is divided into A mass member elastically supported by both of the mounting members by being provided and a second elastic member provided between the mounting members are divided, and by being provided in the dividing portion, the mounting members are elastic. Support And a stopper member that holds the vibration of the mass member at a predetermined value or less and restricts the vibration displacement at a predetermined value or more.

The fluid chamber is partitioned into two chambers by at least one of the mass member and the stopper member, and an orifice for communicating the divided two chambers with each other is provided in either the mass member or the stopper member.

(Operation) With this configuration, in the present invention, the stopper member that allows the vibration of the mass member at the predetermined value or less and regulates the vibration displacement at the predetermined value or more is provided on both the power unit mounting member and the base mounting member. It is elastically supported by dividing the second elastic member across the space and being provided in the divided portion, and the fluid chamber is partitioned into two chambers by at least one of the mass member and the stopper member, and the divided two chambers are Since they are communicated with each other by the orifice provided in either the mass member or the stopper member, when the vibration frequency from the power unit matches the natural resonance frequency of the fluid in the orifice, the fluid in the orifice is excited. Resonates with the vibration, and the vibration of the power unit is damped due to the damping effect (damping effect) due to the resonance of the fluid in this orifice. To be done.

Further, when the vibration frequency of the power unit becomes higher than the resonance frequency of the fluid in the orifice, the fluid does not move through the orifice, and the orifice becomes clogged. Then, when the vibration frequency of the power unit further rises to reach the resonance frequency of the mass member, the mass member resonates in the resonance frequency range, and the resonance causes the mass member to vibrate with a large amplitude. However, in that case, since the orifice is clogged, the two chambers partitioned and formed by at least one of the mass member and the stopper member are in a sealed state independent of each other without exchanging fluid through the orifice, and thus both chambers are closed. Therefore, the damping effect of the stopper member is increased, and the large amplitude vibration of the mass member is suppressed. Therefore, the vibration transmissibility to the base can be reduced.

Then, when the vibration frequency becomes higher than the resonance point of the mass member, the vibration transmissibility greatly decreases.
The transmission of vibration in the muffled sound range of 80 to 100 Hz or higher can be suppressed well, and a so-called low-pass filter effect can be obtained.

(Example) Hereinafter, the Example of this invention is described based on drawing.

FIG. 1 shows a mounting device M according to an embodiment of the present invention.
This mounting device M is used for mounting an automobile engine E as a power unit on a vehicle body B (all of which are partially shown) as a base, and a predetermined portion of the engine E and a vehicle body are shown. It is interposed between the constituent members of B (for example, cross members and side members).

In FIG. 1, reference numeral 1 denotes an engine mounting member to be mounted on an engine E. The engine mounting member 1 is fixed to a substantially hat-shaped mounting plate 2 and a lower surface of the mounting plate 2 integrally at an outer peripheral portion thereof. And a stopper support plate 3 having a substantially dish shape as a partition wall, and these mounting plate 2 and stopper support plate 3
An elastic film 4 made of soft rubber or the like between the outer peripheral portions of
The (diaphragm) is held in a liquid-tight manner. Further, a bolt insertion hole 5 is formed through the center of the mounting plate 2 of the engine mounting member 1, and the mounting bolt 6 inserted into the bolt insertion hole 5 is screwed and fastened to the engine E to mount the engine. The member 1 is attached to the engine E.

On the other hand, 7 is a vehicle body mounting member which is disposed below the engine mounting member 1 and is mounted on the vehicle body B. The vehicle body mounting member 7 includes a disc-shaped mounting plate 8 and an upper surface of the mounting plate 8 and an outer periphery thereof. And a stopper support plate 9 in a substantially hat shape integrally fixed to each other at a portion thereof. A bolt insertion hole 10 is formed at the center of the mounting plate 8 so that the mounting bolt 11 is inserted into the bolt insertion hole 10. The vehicle body mounting member 7 is mounted on the vehicle body B by screwing and fastening the vehicle body B to the vehicle body B.

An upper end surface of a cylindrical engine-side elastic member 12 is integrally fixed in a liquid-tight manner to the outer peripheral portion of the lower surface of the mounting plate 2 of the engine mounting member 1, and the lower end surface of the elastic member 12 is a ring on the inner peripheral surface. It is integrally fixed in a liquid-tight manner to the upper surface of an annular mass member 13 having a groove 13a. An upper end surface of a cylindrical body-side elastic member 14 similar to the engine-side elastic member 12 is integrally fixed to the lower surface of the mass member 13 in a liquid-tight manner, and a lower end surface of the elastic member 14 is formed on the vehicle body. It is fixed in a liquid-tight manner to the outer peripheral portion of the upper surface of the stopper support plate 9 of the member 7. Then, the mounting plate 2 and the stopper support plate 3 in the engine mounting member 1
Between the engine mounting member 1 and the vehicle body mounting member 7, that is, a portion surrounded by the elastic film 4, the mass member 13, both elastic members 12, 14 and the stopper support plate 9 of the vehicle body mounting member 7. A liquid chamber 15 having a variable volume and being sealed is defined by the elastic members 12 and 14 as the fluid chamber 15
A liquid as an incompressible fluid is enclosed in the. Therefore, the elastic film 4 constitutes a part of the wall of the liquid chamber 15, and is deformed according to the change in the pressure in the liquid chamber 15. The elastic members 12 and 14 are the engine mounting member 1
Also, the structure is such that one first elastic member provided between the vehicle body mounting members 7 is divided into two elastic members 12 and 14 at the intermediate portion, and the mass member 13 is provided at the divided portions so that both mounting members are attached. It is elastically supported by 1,7.

A stopper member 16 made of a disk for restricting vibration of the mass member 13 is provided inside the mass member 13 with its outer peripheral edge portion loosely fitted in the ring groove 13a of the mass member 13. The outer peripheral edge of the upper surface of the stopper member 16 and the ring groove 13
The upper surface of the inner wall of a is fixed by a ring-shaped elastic body 17, and the outer peripheral edge of the lower surface of the stopper member 16 and the lower surface of the inner wall of the ring groove 13a are fixed by a ring-shaped elastic body 18 in a liquid-tight manner. The stopper member 16 is elastically supported by the mass member 13 by these elastic bodies 17 and 18. Further, the center portion of the upper surface of the stopper member 16 and the engine mounting member 1
The central portion of the lower surface of the stopper support plate 3 in FIG. 2 is formed by the cylindrical engine-side elastic member 19, and the central portion of the lower surface of the stopper member 16 and the stopper support plate 9 in the vehicle body mounting member 7 described above.
Is fixed to a central portion of the upper surface of the vehicle body by a column-shaped elastic member 20 on the vehicle body side, and the elastic members 19 and 20 are one second elastic member provided between the engine mounting member 1 and the vehicle body mounting member 7.
The elastic member of is divided into two elastic members 19 and 20,
The stopper member 16 is elastically supported by the mounting members 1 and 7 via elastic members 19 and 20 by being provided in the divided portion. With the above structure, the liquid chamber 15 is partitioned by the stopper member 16 into two chambers, the upper chamber 15a and the lower chamber 15b.

Then, on the outer peripheral portion of the stopper member 16, the upper chamber
A first orifice 21, which is an orifice according to the present invention, is formed to penetrate the lower chamber 15b and the lower chamber 15b. Further, a second orifice 22 is formed through the outer peripheral portion of the stopper support plate 3 as a partition wall in the engine mounting member 1, and the resonance frequency f ₁ of the liquid in the first orifice 21 is the mass member 13 The resonance frequency f is lower than the resonance frequency f, and is set to the same level as the vibration frequency of about 10 to 15 Hz at the time of so-called engine shake in which the engine E vibrates in the vertical direction due to the road surface of the automobile, the imbalance of wheels, and the like. On the other hand, the resonance frequency f ₂ of the liquid in the second orifice 22 is 80 to 100H, which is higher than the resonance frequency f in the mass member 13.
It is set to a value greater than or equal to z.

Therefore, in the above embodiment, the first and second orifices in the mounting device M are generated by the vibration force from the engine E as the engine E is vibrating during operation.
The liquid in 21, 21 and the mass member 13 vibrate, and as shown in FIG.
When the resonance frequency f ₁ (about 10 to 15 Hz) peculiar to the liquid inside is matched, the vibration transmissibility to the vehicle body B is reduced due to the damping effect due to the resonance of the liquid inside the first orifice 21, so that the engine shake is prevented. Can be suppressed.

When the frequency of engine vibration becomes higher than the resonance frequency f ₁ of the liquid in the first orifice 21, the first orifice 21 is in a so-called clogging state in which the liquid does not flow inside. The frequency is even higher and the mass member 13
The mass member 13 resonates when it coincides with a predetermined frequency f determined according to the weight of the elastic member and the elastic coefficients of the elastic members 12 and 14.
Then, as indicated by the broken line in FIG. 2, in the frequency range lower than the resonance frequency f, the mass member 13 vibrates in the same phase as the vibration from the engine E, and the body B is vibrated in accordance with the vibration in the same phase. The vibration transmissibility of the mass member 13 increases and reaches a peak at the resonance point f of the mass member 13. On the other hand, when the vibration frequency exceeds the resonance point of the mass member 13 and rises to the muffled sound range, the mass member 13
Vibration is in the opposite phase to the vibration of engine E
When the mass member 13 is stopped, the vibration to the vehicle body B is blocked by the stop of the mass member 13, and the mounting device M serves as a low pass filter to reduce the vibration transmissibility to the vehicle body B in the muffled sound range as high frequency noise. be able to.

In this case, the first orifice 21 causes the liquid chamber 15 to move to the upper chamber 15
The stopper member 16 is provided for partitioning a into a lower chamber 15b, and the stopper member 16 is elastically supported by the engine mounting member 1 and the vehicle body mounting member 7 and is connected to the mass member 13 so as to regulate its vibration. Therefore, the first
When the orifice 21 is in a clogged state, the communication between the upper chamber 15a and the lower chamber 15b is cut off, and each chamber 15a, 15b is closed.
Are independently sealed. Therefore, the stopper member 16 is immovably fixed and held by both the mounting members 1 and 7, and the mass member is regulated by the stopper member 16 in the stopped state.
Even if 13 vibrates with a large amplitude, the vibration is suppressed, so that the vibration transmissibility of the mass member 13 to the vehicle body B in the resonance frequency f range can be effectively reduced as shown by the solid line in the figure. it can.

Further, when the vibration frequency from the engine E further increases and reaches the resonance frequency f ₂ of the liquid in the second orifice 22, the liquid in the second orifice 22 resonates, and the resonance of the liquid causes the above-mentioned mist. The vibration transmissibility in the sound range can be further reduced. In FIG. 2, the alternate long and short dash line indicates the vibration transmissibility characteristic when only the elastic member is provided between the engine mounting member 1 and the vehicle body mounting member 7.

In the above embodiment, the second orifice 22 provided on the stopper support plate 3 of the engine mounting member 1 is not always essential, and instead, a communication hole having a large diameter may be formed. In that case, the resonance transmissibility characteristic for the vehicle body B is as shown in FIG. 3, and the vibration transmissibility in the muffled sound range is affected only by the transmissivity characteristic of the mass member 13. Therefore, the above-mentioned embodiment is preferable in that the vibration transmissibility can be further reduced.

Further, the resonance frequency f ₂ of the liquid in the second orifice 22 may be changed, and the resonance frequency f ₂ may be set to, for example, the mass member 13
When the resonance frequency f of the mass member 13 is made equal to that of the mass member 13, the vibration transmissibility of the mass member 13 to the vehicle body B can be greatly reduced.

(Other Embodiments) The present invention is not limited to the above-described embodiments, but also includes various embodiments as shown in FIGS. 4 and 5, for example. In these embodiments, the same parts as those in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

That is, the embodiment shown in FIG.
Mass member 1 elastically supported between the vehicle body mounting member 7'and the vehicle body mounting member 7 '
3'is arranged on the center side, and its stopper member 16 'is arranged on the outer peripheral side. In this case, the mass member 13 '
Is formed in a columnar shape, and a flange portion 13'b is projectingly provided on the outer peripheral surface thereof. On the other hand, the stopper member 16 'is formed in an annular shape having a ring groove 16'a on the inner peripheral surface thereof.
The flange portion 13'b of the mass member 13 'is provided on the upper and lower surfaces of the inner wall of 16'a.
Is elastically supported. Therefore, the liquid chamber 15 is divided into the upper chamber 15a and the lower chamber 15b by the mass member 13 ', and the first orifice 21' is formed through the mass member 13 '.

Therefore, in this embodiment, the mass member 13 'is at a frequency that produces a muffled sound higher than the resonance point of the mass member 13'.
Vibrate in the opposite phase, the pressure in the lower chamber 15b partitioned and formed by the mass member 13 'acts in a direction of canceling the vibration transmissibility, thereby further reducing the vibration transmissibility in the muffled sound range. is there.

Further, in the embodiment shown in FIG. 5, the stopper member 16 is replaced by the mass member in the same configuration as the first embodiment described above.
Rather than being elastically supported by 13, the ring-shaped elastic bodies 23, 24 fixed to the upper and lower peripheral edges of the stopper member 16 are movably movable with a predetermined clearance d provided in the ring groove 13a of the mass member 13. It has been fitted. In this case, the gap between the outer peripheral edge portion of the stopper member 16 and the inner wall surface of the ring groove 13a of the mass member 13 constitutes the first orifice 21 ″. The member 7 is elastically supported via cylindrical elastic members 19 'and 20', and the liquid chamber 1 is provided outside the elastic members 19 and 20.
5, a separate liquid chamber 25 is formed inside, and a second orifice 22 is formed at the center of the stopper member 16 facing the liquid chamber 25.

Therefore, also in this embodiment, it is possible to obtain the same effects as those of the first embodiment.

In each of the above embodiments, the engine mounting member 1 is placed on the upper side,
Although the vehicle body mounting member 7 is arranged on the lower side, respectively, the positions of both the mounting members 1 and 7 may be reversed, and the same effect as each of the above embodiments can be obtained.

Further, in each of the above-described embodiments, the case of the mounting device M in which the engine E is elastically supported on the vehicle body B has been described. However, in order to reduce vibration, noise, etc., the present invention uses a power unit other than the engine as a base. It goes without saying that it can also be applied to a mounting device that is designed to support.

(Effects of the Invention) As described above, according to the present invention, the fluid chamber and the elastic film, which are disposed between the power unit and the base, and whose volume is variable by the elastic body, are provided between the power unit and the mounting member to the base. And a stopper member for restricting only a vibration displacement of the mass member which is equal to or more than a predetermined value, between the mounting members. The two elastic members are divided and elastically supported by a structure provided in the divided portion, and at least one of the mass member and the stopper member divides the fluid chamber into two chambers, and an orifice communicating the both chambers with each other is formed in the mass member. Since it is provided on at least one of the stopper member and the stopper member, the damping effect associated with the resonance phenomenon of the fluid at the orifice causes a characteristic of a power unit such as an engine shake. It is possible to damp constant frequency vibrations,
In the resonance frequency range of the mass member, the orifices are clogged so that both chambers of the fluid chamber are closed independently to suppress large-amplitude vibrations of the mass member, while at a frequency that produces muffled noise higher than the resonance point of the mass member. The vibration transmissibility to the base can be suppressed to ensure the low-pass filter effect, and thus the sound insulation and vibration damping of the mounting device can be greatly improved with a simple structure.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention, FIG. 1 is a sectional view of a mounting device, FIG. 2 is a characteristic diagram showing a vibration transmissibility characteristic with respect to a vibration frequency of the mounting device, and FIG. It is the same characteristic view in the modification which abbreviate | omitted the 2nd orifice. FIGS. 4 and 5 are views corresponding to FIG. 1 showing another embodiment, respectively. M, M ', M "... Mounting device, 1 ... Engine mounting member, 4 ... Elastic membrane, 7 ... Vehicle mounting member, 12,12',
14,14 '... elastic member, 13,13' ... mass member, 15 ... liquid chamber, 15a ... upper chamber, 15b ... lower chamber, 16,16 '... stopper member, 21,21', 21 ″ …… First orifice, 22 ……
Second orifice, E ... engine, B ... vehicle body.

Claims (1)

[Claims] 1. A mounting device for mounting a power unit such as an engine on a base such as a vehicle body, the base mounting member being mounted on the base, the power unit mounting member being mounted on the power unit, and between the mounting members. A fluid chamber that is provided and is hermetically formed so that the volume can be changed by an elastic body that encloses an incompressible fluid, and that constitutes a part of the wall of the fluid and that deforms according to the pressure change in the fluid chamber. Between the elastic film and the mass member elastically supported by the two mounting members by dividing the first elastic member provided between the both mounting members and being provided in the dividing portion. By dividing the second elastic member provided over the entire length and being provided in the divided portion, the second elastic member is elastically supported by both mounting members, and the vibration variation of the mass member or more is allowed while allowing the vibration of the mass member or less of the predetermined value or less. And a stopper member for restricting the space, the fluid chamber is partitioned into two chambers by at least one of the mass member and the stopper member, and both chambers are provided with an orifice provided in one of the mass member and the stopper member. A power unit mounting device characterized by being communicated with each other.