JPH0989041A - Fluid sealed type mount - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low dynamic spring constant relating to an idle vibration, so that the idle vibration can be effectively absorption suppressed, and in addition, so as to obtain both high damping and high dynamic spring when a shock is input. SOLUTION: A high frequency orifice 25 absorptively suppressing a high frequency vibration, when it is input, is formed with an internal wall of the first fluid chamber 12, an idle orifice 26 absorptively suppressing an idle vibration, when it is input, is formed with a partitioning part 11, and a rubber-shaped elastic material-made orifice valve 16 closely attached to the partitioning part 11 when a shock is input to stop a flow of operating fluid 14 in the idle orifice 26 so as to make the operating fluid 14 flow in only a shock orifice 27, is connected to one mounting part 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid-filled mount used for supporting a vibration body such as an automobile engine in a vibration-proof manner.

[0002]

2. Description of the Related Art As shown in FIG. 5, a liquid-filled mount has conventionally been provided with a low frequency large amplitude (frequency of 10 Hz or less,
Shock orifice a that suppresses vibration of amplitude (around ± 1 mm) (including shock vibration such as when a car rides on a curb, hereinafter also referred to as “shock”) and high-frequency small amplitude (amplitude ± 0.05 mm) And a sub-diaphragm b that suppresses absorption of vibrations (hereinafter, also referred to as “high-frequency vibrations”) (Japanese Patent Publication No. 62-53735).
Reference).

However, with respect to this liquid-filled mount, idle vibration (frequency of about 20 to 30 Hz, amplitude of about 0.2 mm) generated in the idle rotation range is generated.
Is input, the hydraulic fluid does not flow through the shock orifice a, and the sub-diaphragm b does not operate in resonance.
The internal pressure rises and the dynamic spring constant increases. Therefore, this conventional technique has a problem that engine vibration (idle vibration) is largely transmitted in the idle rotation range.

[0004]

In view of the above points, it is an object of the present invention to provide a liquid-filled mount that has a low dynamic spring constant against idle vibration and can effectively absorb and suppress idle vibration. And In addition,
It is an object of the present invention to provide a liquid-filled mount that can obtain both “high damping” and “high dynamic spring” when a shock is input.

For the above second purpose, both "high damping" and "high dynamic spring" are required at the time of inputting a shock for the following reason.

That is, when only "high damping" is obtained and "high dynamic spring" is not obtained, as shown in FIG. 6, a low frequency resonance is generated by the engine and the mount spring-mass system when a shock is input. However, damping can be performed quickly, but the low-frequency resonance immediately after the shock input gives an uncomfortable feeling to the occupant of the vehicle.
Therefore, the resonance frequency does not make the passenger feel uncomfortable.
It is necessary to raise to around 20Hz.

[0007]

In order to achieve the above object, in the liquid-filled mount according to the present invention, one mounting portion and the other mounting portion are connected to each other via an elastic body made of a rubber-like elastic material. A diaphragm is connected to the other mounting portion to provide an airtight space, and a partition portion is provided inside the other mounting portion to define the airtight space as a first liquid chamber on one mounting portion side and a second liquid chamber on the diaphragm side. In the liquid-filled mount in which the working fluid is sealed in both chambers, a high-frequency orifice that suppresses absorption of high-frequency vibration is formed together with the inner wall of the first liquid chamber, and idle vibration is input. Occasionally, an idle orifice that suppresses this absorption is formed together with the partition section, and when a shock is input, it closely contacts the partition section and stops the flow of hydraulic fluid in the idle orifice. Elastomeric material made of orifice valve as hydraulic fluid flows only to click orifice decide to connect to the mounting portion of the one.

[0008]

When a low-frequency, large-amplitude shock is applied to the liquid-filled mount of the present invention having the above-described structure, the orifice valve made of a rubber-like elastic material comes into close contact with the partition, so that the orifice valve is It acts as a spring element in parallel with the elastic body that connects the mounting portion of and the other mounting portion. Therefore, the dynamic spring of the mount is a combination of the dynamic spring of the elastic body and the dynamic spring of the orifice valve, whereby a "high dynamic spring" is realized. Further, since the hydraulic fluid flows only through the shock orifice in this state, "high damping" is realized by the liquid column resonance generated at that time.

When idle vibration is input to the liquid-filled mount of the present invention, the working fluid flows through the idle orifice, so that the liquid column resonance generated at that time realizes a "low dynamic spring", and high frequency. When vibration is input, the working fluid moves in and out of the high-frequency orifice, and the liquid column resonance generated at that time realizes a “low dynamic spring”.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION With respect to the liquid-filled mount of the present invention, when a shock is applied in a direction in which the distance between one mounting portion and the partition portion is reduced, an orifice valve made of a rubber-like elastic material is provided in the partition portion. In order to achieve close contact, it is necessary to place an orifice valve inside one of the mounting parts, that is, in the first liquid chamber, and conversely, a shock is applied in the direction in which the distance between the one mounting part and the partition part increases. In order to bring the orifice valve into close contact with the partition when is input, it is necessary to arrange the orifice valve in the second liquid chamber. Therefore, a through hole that connects both chambers is provided in the partition part, and the partition part is sandwiched in the middle to arrange the first valve part in the first liquid chamber and the second valve part in the second liquid chamber. Is preferably integrally connected via a connecting portion having a relatively small diameter inserted through the through hole.

[0011]

Embodiments of the present invention will now be described with reference to the drawings.

As shown in FIG. 1, one mounting portion 1 provided with a center boss 2 and a mounting bolt 3 and another mounting portion 4 provided with an annular case 5, a cup-shaped lid 6 and a mounting bolt 7. Are connected via an elastic body (also referred to as a rubber leg portion or a mount spring) 8 made of a rubber-like elastic material having an annular shape, and a diaphragm 9 made of a rubber-like elastic material is attached to the other mounting portion 4 at its outer peripheral edge portion. And the airtight space 10 is provided inside the mount surrounded by these.
This airtight space 10 is provided on the other mounting portion 4 (the inner peripheral side of the case 5) by a plate-shaped partition portion (also referred to as a partition member or an orifice plate) 11 on one mounting portion 1 side (upper side) One-liquid chamber (also called main liquid chamber) 12
And a second liquid chamber on the side of the diaphragm 9 (also referred to as a sub liquid chamber)
The chamber 12 is divided into two chambers 12 and 13, and a working liquid (also referred to as an internal sealing liquid) 14 such as a viscous fluid is enclosed in both chambers 12 and 13. The elastic body 8 is vulcanized and adhered to the center boss 2 and the case 5, respectively, and the case 5 is fixed at its lower end by caulking the outer peripheral edge portions of the partition 11, the diaphragm 9 and the lid 6 together. There is. The inside of the lid 6 is open to the atmosphere by a vent hole (not shown). A through hole 15 having a substantially circular plane is provided in the center of the partition portion 11.

An orifice valve 16 made of a rubber-like elastic material and having the following structure is fixed to a bolt 17 below the center boss 2 in one mounting portion 1.

That is, the orifice valve 16 is provided with a frustoconical first valve portion 18 housed in the first liquid chamber 12, and a cylinder is provided at the center of the lower surface of the first valve portion 18. -Shaped connecting portion 19 is integrally formed downward to form the partition portion 11
The disc-shaped second valve portion 20 is integrally molded at the lower end of the connecting portion 19 and is housed in the second liquid chamber 13, and the first valve portion 18 is connected. The bolt insertion hole 16a is provided in the portion 19 and the second valve portion 20 collectively,
A bolt 17 is inserted into the bolt insertion hole 16a from below so that the upper end of the bolt 17 has a center boss 2a.
Screwed to the head of the bolt 17 having a relatively large diameter.
The entire orifice valve 16 is suspended and fixed to the lower side of the center boss 2 while being supported by.

The frusto-conical first valve portion 18 has an outer diameter dimension set larger than an inner diameter dimension of the through hole 15, and has a flat upper surface 1 closely contacting a flat lower surface 2a of the center boss 2.
8a, a tapered outer peripheral surface 18b formed to face the tapered inner peripheral surface 8a of the elastic body 8 via a predetermined gap 21, and a predetermined gap 22 on the flat upper surface 11a of the partition portion 11. Flat lower surface 1 formed to face each other
8c and. The outer diameter of the columnar connecting portion 19 is set to be smaller than the inner diameter of the through hole 15.
The outer peripheral surface 19a is formed so as to face the inner peripheral surface 15a of No. 5 with a predetermined gap 23 in between. The disc-shaped second valve portion 20 has an outer diameter dimension set to be larger than an inner diameter dimension of the through hole, and is formed into a flat lower surface 11 b of the partition portion 11 so as to face the flat lower surface 11 b with a predetermined gap 24 therebetween. Upper surface 2
It has 0a.

Elastic body 8 which is a part of the inner wall of the first liquid chamber 12.
A high-frequency orifice 25 is provided between the tapered inner peripheral surface 8a and the tapered outer peripheral surface 18b of the first valve portion 18 to suppress the absorption of high-frequency vibration of a predetermined frequency. That is, when high-frequency vibration of a predetermined frequency is input to the mount, the hydraulic fluid 14 moves in and out of the gap 21 between the both surfaces 8a and 18b, as shown by the arrow.
The liquid column resonance generated at that time realizes a "low dynamic spring", and this high frequency vibration is effectively absorbed and suppressed.

Between the upper surface 11a of the partition portion 11 and the lower surface 18c of the first valve portion 18, the inner peripheral surface 15a of the through hole 15 and the connecting portion 19 are provided.
The three gaps 22 and 2 described above that make the first liquid chamber 12 and the second liquid chamber 13 communicate with each other between the outer peripheral surface 19a of the partition 11 and between the lower surface 11b of the partition 11 and the upper surface 20a of the second valve portion 20.
A flow path including a combination of 3, 24 is provided, and an idle orifice 26 that suppresses absorption of idle vibration having a predetermined frequency is provided by the flow path. That is, when an idle vibration of a predetermined frequency is input to the mount, the hydraulic fluid 14 flows through this flow path.
Flows, and the liquid column resonance generated at that time realizes a “low dynamic spring”, which effectively absorbs and suppresses this idle vibration.

The idle orifice 26 is blocked when a shock having an amplitude larger than a predetermined value is applied to the mount, and the flow of the hydraulic fluid 14 is stopped. There is. That is, first,
When a shock having an amplitude equal to or larger than the gap 22 is input in the direction in which the distance between the one mounting portion 1 and the partition portion 11 is reduced from the upper side of the drawing, as shown in FIG.
On the lower surface 18c of the partition 11 and the upper surface 11a of the partition 11, the idle orifice 26 is closed and the flow of the hydraulic fluid 14 is stopped. On the other hand, one mounting part 1
When a shock having an amplitude equal to or larger than the gap 24 is input in a direction in which the distance between the partition 11 and the partition 11 increases, the second valve portion 20 has its upper surface 20a at the lower surface 11 of the partition 11.
In close contact with b, the idle orifice 26 is closed and the flow of the hydraulic fluid 14 is stopped.

In the state where the idle orifice 26 is blocked in this manner, the shock orifice 2 is inserted into the orifice valve 16 in order to effectively damp the input shock.
7 are provided. That is, the shock orifice 27 is formed from the outer peripheral surface 18b to the lower surface 18c of the first valve portion 18.
The first orifice hole 28 is provided to extend from the upper surface 20a to the lower surface 20b of the second valve portion 20. The valve portion 18 is opened in the lower surface 18c of the first valve portion 18 so as to communicate with the through hole 15 in a state where the valve portion 18 is in close contact with the partition portion 11, and the second orifice hole 29 and the second valve portion 20 are the partition portion 11. The upper surface 20a of the second valve portion 20 is opened so as to communicate with the through hole 15 in a state of being in close contact with.

Therefore, as a result of this, when a shock having an amplitude larger than the gap 22 is input to the mount in the direction in which the gap between the one mounting portion 1 and the partition portion 11 is reduced, the result is shown in FIG. As described above, the first valve portion 18 comes into close contact with the partition portion 11, the idle orifice 26 is closed, the flow of the hydraulic fluid 14 in the idle orifice 26 is stopped, and the hydraulic fluid 14 flows only through the shock orifice 27. Therefore, “high damping” is realized by the liquid column resonance that occurs at that time, and this shock can be effectively damped. On the other hand, when a shock having an amplitude larger than the gap 24 is input to the mount in the direction in which the distance between the one mounting portion 1 and the partition portion 11 increases, the second valve portion 20 causes the partition portion to move. 11, the idle orifice 26 is closed, the flow of the hydraulic fluid 14 in the idle orifice 26 is stopped, and the hydraulic fluid 14 flows only through the shock orifice 27. "High damping" is achieved, which allows this shock to be damped effectively.

The liquid-filled mount having the above structure is
For example, the other mounting portion 4 is mounted on the vehicle body side of the vehicle, and the one mounting portion 1 is mounted on the engine side of the vehicle to elastically support the engine while exhibiting a vibration damping effect. When a high-frequency vibration of a predetermined frequency is input to the mount, the working fluid 14 moves in and out of the high-frequency orifice 25, so that the liquid column resonance generated at this time realizes a "low dynamic spring". Can be effectively suppressed. When an idle vibration of a predetermined frequency is input to the mount, the idle orifice 26
Since the hydraulic fluid 14 flows through the liquid cylinder, a liquid column resonance generated at this time realizes a "low dynamic spring" as shown in FIG. 4, and this idle vibration can be effectively absorbed and suppressed.

When a shock having an amplitude larger than the preset clearances 22 and 24 is input to the mount, the first valve portion 18 or the second valve portion of the orifice valve 16 is input depending on the input direction. Since the part 20 is in close contact with the partition part 11, the orifice valve 16 acts as a spring element in parallel with the elastic body 8. Therefore, since the dynamic spring of the mount is a combination of the dynamic spring of the elastic body 8 and the dynamic spring of the orifice valve 16, a "high dynamic spring" is realized as shown in FIG. Since it is pulled up more than before, it is possible to prevent an occupant of the vehicle from having an unpleasant feeling. Further, since the hydraulic fluid 14 flows only through the shock orifice 27 in this state, the liquid column resonance generated at that time causes
"High damping" is achieved, as shown in Figure 3, which allows this shock to be damped effectively.

[0023]

The present invention has the following effects.

That is, in the liquid-filled mount of the present invention having the above structure, when idle vibration of a predetermined frequency is input to the mount, hydraulic fluid flows through the idle orifice, which occurs at this time. A liquid column resonance realizes a "low dynamic spring". Therefore, this makes it possible to effectively absorb and suppress this idle vibration. At the same time, since both "high damping" and "high dynamic spring" can be obtained at the time of inputting a shock, the resonance frequency can be increased more than before. Therefore, it is possible to prevent the passengers of the vehicle from feeling uncomfortable.

[Brief description of drawings]

FIG. 1 is a sectional view of a liquid-filled mount according to an embodiment of the present invention.

FIG. 2 is a sectional view showing an operating state of the liquid-filled mount.

FIG. 3 is a graph showing changes in the dynamic spring constant of the liquid-filled mount in the low frequency range.

FIG. 4 is a graph showing a change in a dynamic spring constant of the liquid-filled mount in an idle rotation range.

FIG. 5 is a cross-sectional view of a liquid-filled mount according to a conventional example.

FIG. 6 is an explanatory view showing how the resonance system should be in a vehicle body, a liquid-filled mount, and an engine.

[Explanation of symbols]

 1 One mounting part 2 Center boss 2a, 11b, 18c, 20b Lower surface 3,7 Mounting bolt 4 Other mounting part 5 Case 6 Lid 8 Elastic body 8a, 15a Inner peripheral surface 9 Diaphragm 10 Airtight space 11 Partition part 11a, 18a , 20a upper surface 12 first liquid chamber 13 second liquid chamber 14 hydraulic fluid 15 through hole 16 orifice valve 16a bolt insertion hole 17 bolt 17a head portion 18 first valve portion 18b, 19a outer peripheral surface 19 connecting portion 20 second valve portion 21 , 22, 23, 24 Gap 25 High frequency orifice 26 Idle orifice 27 Shock orifice 28 First orifice hole 29 Second orifice hole

Claims (1)

[Claims] 1. One mounting portion (1) and the other mounting portion (4) are connected via an elastic body (8) made of a rubber-like elastic material, and a diaphragm (9) is attached to the other mounting portion (4). ) Are connected to each other to provide an airtight space (10), and a partition portion (11) is provided inside the other attachment portion (4) to connect the airtight space (10) to the first attachment portion (1) side. Liquid chamber (1
2) and a second liquid chamber (13) on the side of the diaphragm (9), and a high-frequency vibration is input in a liquid-filled mount in which the working liquid (14) is sealed in both chambers (12) and (13). High-frequency orifice (2
5) is formed with the inner wall of the first liquid chamber (12), and an idle orifice (26) for suppressing absorption of idle vibration is formed with the partition part (11) when a shock is input. Closely adheres to the partition (11), and the hydraulic fluid (1) in the idle orifice (26)
4) Stopping the flow of 4) and connecting the orifice valve (16) made of a rubber-like elastic material to the one mounting portion (1) so that the hydraulic fluid (14) flows only through the shock orifice (27). Characteristic liquid-filled mount.