JPS6323931B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a composite engine mount for a vehicle engine, and more specifically, a space formed by fixing an engine-side mounting member and a vehicle front-side mounting member to both sides of a cylindrical body made of an elastic material. A partition plate provided with an orifice and a diaphragm made of an elastic material are arranged, and the space is divided into a first working fluid chamber located on one side of the partition plate and inside the cylinder, and a first hydraulic fluid chamber located on the other side of the partition plate. and a compound engine divided into a second hydraulic fluid chamber located between one side of the diaphragm and communicating with the first hydraulic fluid chamber via the orifice, and a volume correction chamber located on the other side of the diaphragm. Regarding the mount.

In general, vehicle engine mounts have two functions: absorb low-frequency displacement inputs with large displacements to suppress engine vibrations caused by uneven road surfaces, and absorb high-frequency displacement inputs with small displacements to suppress engine vibrations. There is a need for a function that suppresses the transmission of noise into the vehicle interior and suppresses the increase in interior noise. The above-mentioned composite engine mount was developed to meet this demand. It absorbs low-frequency displacement input through the damping effect that occurs when the hydraulic fluid in both hydraulic chambers passes through the orifice, and The cylindrical body made of an elastic material such as the above is configured to absorb high-frequency displacement input through the vibration-proofing action. Therefore, in this type of composite engine mount, it is advantageous to reduce the opening area of the orifice to produce a large damping effect in order to absorb low-frequency displacement input; Then, the vibration-proofing effect of the cylindrical body decreases,
This is disadvantageous for absorbing high frequency displacement input. On the other hand, if you increase the opening area of the orifice,
The vibration isolation effect of the cylinder increases, but the damping effect decreases. That is, the damping effect and the vibration isolation effect are mutually contradictory characteristics for this type of composite engine mount, and the reality is that a composite engine mount that sufficiently provides both of these functions has not yet been proposed.

The present invention has been made in view of the above-mentioned circumstances, and its main purpose is to provide a composite engine mount with sufficient damping and vibration-proofing effects. explain.

1 and 2 show an example of a composite engine mount according to the present invention. This composite engine mount includes a cylindrical body 10 made of an elastic material such as rubber, a vehicle body side mounting member 20 fixed to the lower end of the cylindrical body 10, an engine side mounting member 30 fixed to the upper end of the cylindrical body 10, and a cylindrical body 10. A partition plate 41 and a diaphragm 42 made of an elastic material such as rubber are arranged between the engine-side mounting member 30 and a sheet-like partition member 51 which is the main part of the present invention and which is arranged inside the cylinder 10 and rubber which is an elastic body. It is composed of a columnar body 52.

A vehicle body side mounting member 20 is vulcanized and fixed to the lower end of the cylinder 10, and an engine side mounting member 30 is fixed to the mounting flange 11, which is vulcanized and adhered to the upper end of the cylinder 10, with a plurality of mounting bolts. Fixed. The vehicle body side mounting member 20 is composed of a lid body 21 that covers the lower end opening of the cylinder body and a mounting bolt 22 fixed to the center part of the lid body 21.
A through hole 21a is formed in. The engine-side mounting member 30 is composed of a bowl-shaped lid 31 that covers the upper end opening of the cylinder 10 and a mounting bolt 32 fixed to the center of the bowl-shaped lid 31. It is fixed to the mounting flange 11 via. The partition plate 41 is equipped with an orifice 41a in the center, and the cylindrical body 10,
Vehicle side mounting member 20 and engine side mounting member 3
0 is divided into an internal space of the cylinder 10 and an internal space of the engine side mounting member 30. Also,
The diaphragm 42 is located between the partition plate 41 and the engine-side mounting member 30, and has a second hydraulic fluid chamber R 1 on one side of the diaphragm 42 that communicates with a first hydraulic fluid chamber R ₁ to be described later.
A working fluid chamber R ₂ is formed, and a volume correction chamber R ₀ is formed on the other side. Both working fluid chambers R ₁ and R ₂
is sealed with a working fluid such as water, and the volume correction chamber _R0 is sealed with air.

Thus, a sheet-like partitioning member 51 and a rubber columnar body 52 are arranged in a space inside the cylinder 10 formed on one side of the partition plate 41. The sheet-like partition member 51 is a reinforced rubber sheet that includes a base fabric, and is not elastic in itself, but has flexibility. This sheet-like partition member 51 is sandwiched between the cylinder body 10 and the engine-side mounting member 30 together with the partition plate 41 and the diaphragm 42, and is located in the space within the cylinder body 10. In addition, the rubber columnar body 52
is provided with an annular recess 52a having a wedge-shaped cross section on the outer periphery of the approximately central portion in the longitudinal direction, and is fixed to the center portion of the vehicle body side mounting member 20 by vulcanization adhesive etc., and the sheet-like partition member 51 is attached to one side thereof. Supports in a relaxed state. As a result, the sheet-like partition member 51
The space inside 0 is divided into two parts, and an air chamber _R3 communicating with the atmosphere through the through hole 21a of the vehicle body side mounting member 20 is formed on one side, and a partition plate 41 is formed on the other side.
A first hydraulic fluid chamber R ₁ is formed which communicates with the second hydraulic fluid chamber R ₂ through the orifice 41a. The first hydraulic fluid chamber R ₁ and the second hydraulic fluid chamber R ₂ are sealed with hydraulic fluid. The rubber columnar body 52 is
When the engine is attached to the vehicle body, the annular recess 52a remains, and due to the annular recess 52a, it changes due to a high frequency displacement input with a small amount of displacement, and disappears due to a low frequency displacement input with a large amount of displacement. A predetermined gap (recess gap) is formed, and as the recess gap decreases, the first hydraulic fluid chamber
It is designed to suppress the volume reduction of R ₁ .

In the composite engine mount configured in this manner, when there is no relative displacement between the vehicle body and the engine and no displacement input is applied, the rubber columnar body 52 leaves the recess gap of the annular recess 52a. In this state, when a high-frequency displacement input with a small amount of displacement is applied, the rubber columnar body 52 changes the recess gap of the annular recess 52a and
It absorbs the relative displacement between 0 and 30, and both working fluid chambers R ₁ ,
Does not cause a relative change in the volume of _R2 . Therefore, there is no flow of hydraulic fluid between the two hydraulic fluid chambers R ₁ and R ₂ and no damping action occurs, and the high frequency displacement input is absorbed by the vibration damping action of the cylindrical body 10, and the engine vibration is transferred to the casing. The transmission of information will be suppressed. On the other hand, when a low-frequency displacement input with a large amount of displacement is applied, a situation occurs in which the recess gap of the annular recess 52a of the rubber columnar body 52 disappears and the volume of the _first hydraulic fluid chamber R1 decreases. A relative change between the two mounting members 20, 30 causes a relative change in the volumes of the two hydraulic fluid chambers _R1 , _R2 . Therefore, the hydraulic fluid between the two hydraulic fluid chambers R ₁ and R ₂ flows through the orifice 41a to produce a damping effect, and the low frequency displacement input is absorbed by this damping effect, thereby suppressing engine rocking.

As described above, in this embodiment, when high frequency displacement input is applied, both mounting members 20 and 3
The rubber columnar body 52 absorbs the relative displacement between 0 and 0 so as not to cause a relative change in the volumes of both working fluid chambers R ₁ and R ₂ , and when a low frequency displacement input is applied. is configured so that relative displacement between the mounting members 20 and 30 on both sides causes a relative change in the volumes of both working fluid chambers R ₁ and R ₂ . Therefore, even if the opening area of the orifice 41a is set to produce an optimal damping effect for absorbing low frequency displacement input, the vibration damping effect of the cylindrical body 10 is not impaired. Therefore, according to this embodiment,
A composite engine mount with sufficient damping and vibration isolation can be provided.

Further, in this embodiment, both mounting members 20,
Since the cylindrical body 10 that causes a relative displacement of 30 and the rubber columnar body 52 that converts this relative displacement into a relative change in the volume of both working fluid chambers R ₁ and R ₂ are separated, the above-mentioned During operation, both hydraulic fluid chambers R ₁ ,
The internal pressure of R ₂ hardly affects the cylinder 10, and the damping effect and the vibration isolation effect do not decrease due to a decrease in the elasticity of the cylinder 10 (increase in the spring constant). Furthermore, in this embodiment, a reinforcing rubber sheet that includes the base fabric and does not have elasticity itself is used as the sheet-like partition member 51.
A stable damping effect can be obtained when a low frequency displacement input is applied.

In this embodiment, an example is shown in which a multi-reinforced rubber sheet containing a base fabric is used as the sheet-like partition member 51, but a flexible sheet that does not have elasticity itself may be used instead of the reinforcing rubber sheet. can be adopted respectively. Moreover, the present invention
A partition plate with an orifice and a diaphragm made of an elastic material are arranged in a space formed by fixing an engine side mounting member and a vehicle body side mounting member to both ends of a cylinder made of an elastic material, and the space is closed. a first hydraulic fluid chamber located on one side of the partition plate and within the cylindrical body; a first hydraulic fluid chamber located between the other side of the partition plate and one side of the diaphragm and communicated with the first hydraulic fluid chamber via the orifice; The present invention can be applied to various types of composite engine mounts that are partitioned into a second hydraulic fluid chamber and a volume correction chamber located on the other side of the diaphragm.

As explained above, the present invention provides the various types of composite engine mounts described above, in which a flexible sheet-like partition member is disposed on one side of the partition plate, and a flexible sheet-like partition member is disposed on one side of the partition member in the cylinder body. The first hydraulic fluid chamber is airtightly partitioned to form an air chamber that communicates with the atmosphere, and the air chamber fluctuates due to high-frequency displacement input with a small amount of displacement and is caused by low-frequency displacement input with a large amount of displacement. An elastic body having a predetermined gap that disappears and suppressing a decrease in the volume of the first hydraulic fluid chamber due to a decrease in the gap is provided, and the partition member is supported in a relaxed state on one side thereof. There is a characteristic of its composition. Therefore, according to the present invention, when a high frequency displacement input is applied, the relative displacement between the two mounting members is absorbed by the spring member, so that no relative change occurs in the volumes of the two working fluid chambers, and When a low frequency displacement input is applied, the relative displacement between both mounting members can cause a relative change in the volume of both hydraulic fluid chambers, thereby providing sufficient damping and vibration isolation effects. Composite engine mounts can be provided.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an example of a composite engine mount according to the present invention, and FIG. 2 is a plan view thereof. Explanation of symbols: 10...Cylinder body, 20...Vehicle side mounting member, 30...Engine side mounting member, 41...Partition plate,
41a... Orifice, 42... Diaphragm, 51
...Sheet-like partition member, 52...Rubber columnar body, R ₀
…Volume correction chamber, R ₁ , R ₂ … Working fluid chamber, R ₃ … Air chamber.

Claims (1)

[Claims] 1 A partition plate with an orifice and a diaphragm made of an elastic material are arranged in a space formed by fixing an engine-side mounting member and a vehicle-side mounting member to both ends of a cylinder made of an elastic material, and the space is closed. into a first hydraulic fluid chamber located on one side of the partition plate and within the cylindrical body, and a first hydraulic fluid chamber located between the other side of the partition plate and one side of the diaphragm through the orifice. In a composite engine mount that is partitioned into a communicating second hydraulic fluid chamber and a volume correction chamber located on the other side of the diaphragm, a flexible sheet-like partition member is disposed on one side of the partition plate. An air chamber that is airtightly separated from the first working fluid chamber and communicates with the atmosphere is formed on one side of the partition member in the cylindrical body. In addition, an elastic body is provided that has a predetermined gap that disappears due to a low-frequency displacement input having a large amount of displacement, and suppresses a decrease in the volume of the first working fluid chamber due to a decrease in the gap, so that the partition member is A composite engine mount for a vehicle engine, characterized in that it is supported in a relaxed state on one side.