JP4227138B2 - Liquid filled vibration isolator - Google Patents

Description

  The present invention relates to a liquid-filled vibration isolator having an anti-vibration mechanism formed so as to cut off vibration in a specific frequency range, and in particular, two frequencies such as engine idling vibration and engine shake vibration. The present invention relates to a liquid-filled vibration isolator that exhibits a high damping characteristic in any case, and thereby attenuates both the vibrations.

  Among anti-vibration devices, especially in the case of engine mounts for automobiles, the engine as the power source is used under various conditions from idling to the maximum rotational speed. Therefore, it must be able to handle a wide range of frequencies.

For this reason, there are two liquid chambers in the interior, which communicate with each other with an orifice, and that the liquid in the orifice is made to resonate at a specific frequency, etc. An apparatus has been devised and is already known. And among such a liquid enclosure type vibration isolator, as a type which has two orifices, the thing of the following patent document 1 etc. are mentioned, for example.
JP 2001-20992 A (Page 2-5, FIG. 1-3)

  By the way, the thing of the said literature reduces the dynamic spring constant of this vibration isolator whole by the liquid-column resonance action of the liquid which exists in one orifice, thereby trying to cut off idling vibration, With respect to engine shake vibration, which is a problem during traveling, a damping function is exhibited by the action of a damping force based on the flow resistance of the liquid in the other orifice.

  However, recent automobile engines employ a lean combustion system or a low engine idling rotational speed from the viewpoint of reducing fuel consumption, and the idling operation state of the engine is unstable. As a result, the occurrence of vibrations in the rotational 0.5 frequency range of the engine is a problem.

  The present invention provides a liquid-filled vibration isolator that performs the above-described suppression of idling vibration in a low frequency range by a high damping function of an orifice for idling vibration.

  In order to solve the above-mentioned problems, the following measures are taken in the present invention.

Specifically, in the first aspect of the invention, the first connecting member attached to the vibrating body, the second connecting member attached to the vehicle body side member, the first connecting member and the second connecting member. A rubber-like insulator that absorbs and blocks vibration from the vibrating body, a first diaphragm that is axially spaced from the insulator, and a gap between the insulator and the first diaphragm The chamber wall is formed in a part of the insulator, and a main chamber in which liquid is sealed is communicated with the main chamber via a first orifice, and the first diaphragm A sub-chamber in which a part of the chamber wall is formed, a partition component that partitions between the main chamber and the sub-chamber, and a partition wall in the partition component that is a second diaphragm with respect to the main chamber Part of In the liquid-filled vibration isolator of the type having two orifices, which is composed of a third liquid chamber that is partitioned and a second orifice that communicates between the third liquid chamber and the sub chamber. Two orifices are provided on the outside of the third liquid chamber in the partition component to form an annular double winding shape in plan view, and the first orifice is provided on the outside of the second orifice. The second orifice has an orifice length longer than the orifice length of the first orifice, and is formed in a circular arc shape in plan view formed by a part of the ring . A configuration is adopted in which the opening hole on the sub chamber side of the second orifice has a smaller opening area than the communication port on the sub chamber side of the first orifice .

  According to the vibration isolator of the present invention adopting such a configuration, it is possible to reduce engine idling vibration, particularly vibration in a low frequency (low frequency) region corresponding to engine rotation 0.5th order vibration. become able to.

  In particular, in the present invention, by making one of the orifices correspond to the engine rotation 0.5 order vibration, such low frequency (low frequency) vibrations can be reduced, and the other one can be reduced. By making the orifice correspond to engine rolling vibration and engine shake vibration, both engine vibration can be suppressed (vibrated) or shut off during engine idling operation and vehicle travel.

In the liquid filled type vibration damping device of the present invention, the first orifice may have a cross-sectional area smaller than a cross-sectional area of the second orifice. In addition, the partition component is a member that forms both the first and second orifices and the third liquid chamber, and a lower side of the third liquid chamber and the second orifice. A partition wall between the double-winding inner and outer passages of the member forming the orifice may be formed of a rubber-like member, and the partition wall may be brought into contact with the partition plate. In this case, by combining the first and second orifices and the member forming the third liquid chamber with a partition receiving plate provided in contact with the lower surface thereof, the two orifices including the double-wound orifice are included. The orifice structure can be easily configured, and the partition wall between the double-winding inner and outer passages is formed by a rubber-like member, and is made to contact the partition receiving plate that closes the lower side by the rubber-like member. Unlike the case of contact with each other, the contact portion is well maintained in a liquid-tight state, there is no risk of short circuit due to leakage, and the effect of having the second orifice in a double winding configuration can be sufficiently exhibited. .

In the liquid-filled vibration isolator of the present invention, the partition wall between the double-winding inner and outer passages, together with the inner partition wall that defines the second orifice and the third liquid chamber, The diaphragm may be formed of a rubber-like member integral with the diaphragm, and both partition walls may be brought into contact with the partition receiving plate . In this case, not only a short circuit between the inner and outer passages of the second orifice in the double winding form, but also a short circuit between the second orifice and the third liquid chamber can be prevented.

The liquid-filled vibration damping device of the present invention, the first orifice and the second orifice, to the input of the input and the engine shake vibration of the engine idling vibrations, it is made to both exhibit high damping characteristics Good .

  According to such a configuration, engine idling vibration and engine shake vibration during vehicle traveling can be suppressed (vibrated).

  That is, in the case of the present invention, since both the orifices are set so as to have a high damping characteristic, the engine rotation 0.5 order vibration during engine idling operation or the engine rolling vibration during engine idling operation It can be suppressed (damped) by the high damping force formed by the two orifices. As a result, it is possible to efficiently suppress vibrations of a relatively low frequency that occur during engine idling operation.

  Further, the suppression (vibration suppression) of the engine shake vibration generated during the traveling of the vehicle can be suppressed (vibration suppression) by the damping force of the orifice. Thus, in the present invention, both low-frequency vibrations during engine idling and engine shake vibrations generated during vehicle travel are both suppressed by the high damping force formed by the two orifices. Thus, the vibration damping action is effectively exhibited.

  As described above, according to the present invention, as a liquid-filled vibration isolator having two orifices, a low frequency of about 5 to 20 Hz corresponding to engine idling vibration, in particular, engine rotation 0.5th order vibration. The vibration in the (low frequency) region can be effectively reduced.

  In particular, in the present invention, by making one of the orifices correspond to the 0.5th order vibration of the engine, such low frequency (low frequency) vibration can be reduced and the other orifice can be reduced. Therefore, the engine vibration can be suppressed (vibrated) or cut off during engine idling and when the vehicle is running.

  Next, embodiments of the present invention will be described with reference to the illustrated examples.

  FIG. 1 is a longitudinal sectional view of a liquid-filled vibration isolator according to the present embodiment, FIG. 2 is a partial sectional view different from FIG. 1, and FIG. 3 is an orifice forming member constituting a partition component. It is a top (bottom) figure from the lower surface side of a liquid chamber formation member.

  As shown in FIG. 1, the liquid-filled vibration isolator of the present embodiment includes a first connecting member 1 attached to a vibrating body, a second connecting member 2 attached to a member on the vehicle body side, and the like. A rubber-like insulator 3 between one connecting member 1 and the second connecting member 2 for absorbing and blocking vibration from the vibrating body, and a first diaphragm facing the insulator at an interval in the axial direction (First diaphragm) 4 and a main chamber 5 in which a chamber wall is formed between a portion of the insulator 3 between the insulator 3 and the first diaphragm 4 and in which a liquid is enclosed. The main chamber 5 is communicated with a first orifice (first orifice) 7 so that liquid is sealed in the same manner as the main chamber, and a part of the chamber wall is defined by the first diaphragm 4. Sub-chamber 6 and A partition component 10 for partitioning the chamber 5 and the sub chamber 6, and a part of the chamber wall in the partition component 10 is partitioned by the second diaphragm 20 with respect to the main chamber 5. A third liquid chamber 8 and a second orifice (second orifice) 9 for communicating between the third liquid chamber 8 and the sub chamber 6 are provided.

  The partition component 10 includes an annular orifice forming member 11 provided with the first orifice 7 and the second orifice 9 and the like, and the second diaphragm 20 is formed at an inner central portion of the orifice forming member 11. A liquid chamber forming member 12 made of a rubber-like member forming the third liquid chamber 8, and the orifices forming the lower surface of the orifice forming member 11 and the liquid chamber forming member 12, and the second orifice 9 and the third liquid chamber. 8 and a partition receiving plate 13 that blocks the lower surface of 8 and partitions between the sub chamber 6.

  Most of the orifice forming member 11 is formed of a material having rigidity such as a plastic material or an aluminum alloy material, and has a ring shape in plan view, as shown in FIG. First and second orifices 7 and 9 are formed. Specifically, the outer circumferential surface of the orifice forming member 11 is formed with a substantially circular (circular arc) concave groove that is formed in the upper cylindrical shape of the second connecting member 2. The groove is formed as the first orifice 7 by being fitted to the inner periphery of the portion 24. The first orifice 7 communicates between the main chamber 5 and the sub chamber 6, and one end side of the orifice 7 communicates with the main chamber 5 through a communication port 71 provided at the upper peripheral edge of the orifice forming member 11. As shown in FIG. 2, the other end side communicates with the sub chamber 6 through a communication port 131 provided in the partition receiving plate 13 from a notch 72 formed on the lower surface side of the orifice forming member 11.

  Inside the first orifice 7, the second orifice 9 having a double winding shape is provided around the third liquid chamber 8 by a groove opening downward. The second orifice 9 communicates between the sub chamber 6 and the third liquid chamber 8, and operates based on the vibration input transmitted to the liquid in the main chamber 5. The operation of the two diaphragms 20 (see FIG. 1) causes the liquid in the third liquid chamber 8 to flow to the sub chamber 6 side. More specifically, the second orifice 9 is folded back and returned to a double-winding shape when it has made one round around the opening 91 on the third liquid chamber 8 side as a base point. It communicates with the sub chamber 6 via the opening hole 132 that is provided. Reference numeral 92 denotes a folded portion of the double-winding inner and outer passages 9a and 9b. The partition wall 93 between the inner and outer passages 9a and 9b and the inner partition wall 94 between the third liquid chamber 8 in the second orifice 9 are formed by a rubber-like member integrated with the liquid chamber forming member 12 as will be described later. ing.

  The liquid chamber forming member 12 has a cup shape formed of a rubber-like member, and is provided inside the first and second orifices 7 and 9. A central recess of the liquid chamber forming member 12 is provided with a recessed portion that opens downward to form the third liquid chamber 8, and a space between the main chamber 5 is defined above the recessed portion. The second diaphragm 20 to be formed is integrally provided. The liquid chamber forming member 12 is integrally coupled to the orifice forming member 11 by vulcanizing and bonding means, and the third liquid chamber 8 communicates with the second orifice 9 through an opening 91. (See FIG. 3).

  In the above-described two-orifice configuration, one of the first and second orifices, mainly the outer first orifice 7, has a low value corresponding to the engine rotation 0.5th order frequency among idling vibrations. It is formed for the purpose of damping frequency vibrations. Therefore, in order to suppress the rotation 0.5 order vibration of the engine, it is formed outside the orifice forming member 11 as described above so as to obtain a high damping force with respect to the input of the low frequency vibration.

  The partition receiving plate 13 is provided in contact with the lower surfaces of the orifice forming member 11 and the liquid chamber forming member 12 having the above-described configuration, and the lower opening side of the third liquid chamber 8 and the second orifice 9 serves as the sub chamber 6. On the other hand, it is provided so as to shut off in a liquid-tight manner (see FIG. 1).

  The partition receiving plate 13 basically has a disk shape, and is formed of a press-formed product based on a steel plate, a formed product of an aluminum alloy plate, or the like.

  And, on the disc-shaped partition receiving plate 13, the liquid chamber forming member 12 made of a rubber material or EPDM or the like, and the orifice forming member 11 made of an annular shape are provided in contact with each other, When the members 11 and 12 are held in pressure contact, the third liquid chamber 8 and the second orifice 9 are formed as described above. As a result, the orifice forming member 11 and the liquid chamber forming member 12 are in close contact with the partition receiving plate 13.

  In particular, in the case of the present invention, the partition wall 93 between the inner and outer passages 9a and 9b of the double-wound second orifice 9 together with the inner partition wall 94 between the third liquid chamber 8 and the liquid chamber forming member 12 Formed by an integral rubber member, both the partition walls 93 and 94 are in liquid-tight contact with the partition receiving plate 13. Therefore, unlike the case of contact between metals, the contact portion is held well in a liquid-tight state, and there is no possibility of short circuit due to leakage. Further, a short circuit between the second orifice 9 and the third liquid chamber 8 is also prevented. Therefore, the sealing performance in the double-wound second orifice 9, the third liquid chamber 8 and the like is enhanced, and the effect obtained by making the second orifice 9 into the double-winding form can be sufficiently exhibited. Become.

  In the case of the illustrated embodiment, the partition wall 93 between the inner and outer passages 9a and 9b is provided with a convex portion 95 projecting downward from the upper plate portion of the orifice forming member 11 inside the rubber-like member. 93 is reinforced.

  A flange 133 is provided at a peripheral end portion of the partition receiving plate 13, and at the flange 133, the second connecting member 2 extends from the peripheral portion of the insulator 3 so as to seal the outer periphery of the orifice forming member 11. The rubber part 33 extended along the inner periphery of the cylindrical part 24 and the auxiliary metal fitting 41 on the peripheral part of the first diaphragm 4 are joined together and are joined together, and these are joined to the second connecting member 2. It is combined with the peripheral part of this by clinch coupling means or the like.

  Thus, the orifice forming member 11 is liquid-tightly fitted to the inner periphery of the cylindrical portion 24 of the second connecting member 2, and the second tire member 4 and the partition receiving plate 13 together with the second By being integrally coupled to the peripheral portion of the connecting member 2, a sub chamber 6 defined by the first diaphragm 4 and the like is formed between the partition receiving plate 13 and the first diaphragm 4. It will be.

  The partition receiving plate 13 that partitions and forms the upper portion of the sub chamber 6 as described above has a communication port 131 on the sub chamber side of the first orifice 7 and an opening hole 132 on the sub chamber side of the second orifice 9. Is provided.

  Next, an operation mode and the like for the embodiment of the present embodiment having such a configuration will be described.

  As shown in FIG. 1, vibration from the vibrating body side is propagated to an insulator 3 made of a rubber material or the like via the upper first connecting member 1. Accordingly, the insulator 3 vibrates or deforms to absorb or block most of the input vibration. Therefore, most vibrations are cut off at the insulator 3, but some of them are not cut off at the insulator 3, and each chamber in which the next liquid is enclosed, that is, the main chamber 5. The sub chamber 6, the third liquid chamber 8, and the orifices 7 and 9 are blocked.

  Next, specific actions in each chamber and orifice will be described. First, for the input of engine idling vibration, the following measures are taken in the embodiment.

  That is, the idling vibration that is a target in the embodiment of the present embodiment is a vibration in a very low frequency range from about 5 Hz to about 20 Hz corresponding to the engine rotation 0.5th order vibration. It is difficult to cut off this vibration by reducing the dynamic spring constant of the engine mount as in the conventional case. Further, in the conventional system, as shown in the conventional line (B) in FIG. 4, the damping characteristic has a peak value when engine shake vibration having a specific frequency (frequency) is targeted. In other frequency ranges, almost no damping force is generated. Therefore, in the conventional system, it is impossible to suppress (suppress) the 0.5th-order vibration of the engine by the damping force of the engine mount.

  In view of such points, in this embodiment, the low frequency vibration is suppressed by increasing the damping function of the orifice with respect to the low frequency vibration input from about 5 Hz to 20 Hz (damping). To do).

  Specifically, when the low-frequency vibration is transmitted to the liquid in the main chamber 5 via the insulator 3, first, the liquid existing in the main chamber 5 is transferred to the sub-chamber 6 side via the first orifice 7. Make it flow. A predetermined damping force is exerted by the flow resistance of the liquid in the first orifice 7 to suppress the 0.5th-order vibration of the engine. That is, as shown in part a1 of the embodiment (A) line in FIG. 4, a high damping force is exerted with respect to a vibration input of about 5 Hz, thereby rotating the engine having a frequency of about 5 Hz. Suppress (suppress) 0.5th order vibration.

  Further, in the embodiment, engine rolling vibration in the frequency region around 15 Hz is a problem with respect to engine idling vibration, and vibration suppression is also required. The damping function of the engine rolling vibration in the frequency range around 15 Hz is also dealt with by enhancing the damping function of the engine mount in the embodiment.

  Specifically, the engine rolling vibration around 15 Hz is suppressed (damped) by the damping function formed by the second orifice 9 provided in a double winding shape inside the first orifice 7. [Refer to part a2 of the embodiment (A) line in FIG. 4] That is, in response to the input of the engine rolling vibration, the second diaphragm 20 facing the main chamber 5 vibrates. In response to the vibration 20, the liquid in the third liquid chamber 8 flows from the opening 91 to the second orifice 9, and passes through the second orifice 9 from the opening hole 132 provided in the partition receiving plate 13. The flow of the liquid in the second orifice 9 causes a high damping force with respect to a frequency (frequency) of around 15 Hz as shown in the a2 portion of the embodiment (A) line in FIG. Gain Is thus made. Engine rolling vibrations by the high damping force (are damping) Osaekoma is a thing.

  Regarding the engine shake vibration, which is a problem during the running of the vehicle, in the present embodiment, the frequency value of the engine shake vibration is in the range of 10 to 15 Hz. Therefore, it is suppressed (vibrated) by a damping force based on the flow action of the liquid in the second orifice 9. Specifically, in the present embodiment, a high attenuation characteristic is mainly obtained with respect to the input of the engine shake vibration by appropriately setting the diameter and length of the second orifice 9 shown in FIG. Make it work. As a result, engine shake vibration that occurs during vehicle travel is effectively suppressed (damped).

  As described above, in the embodiment of the present embodiment, each main chamber 5, sub chamber 6, third liquid chamber is used for vibration isolation during idling operation including low frequency including engine rotation 0.5th order vibration. 8 and the first and second orifices 7 and 9 can be suppressed (damped) by a high damping force. Further, by using these orifices, it is possible to suppress engine shake vibration, which is a problem during vehicle travel.

  The characteristic diagram of FIG. 4 shows the embodiment device (example) of the present invention in which the inner second orifice forms a double winding form, and the one disclosed in Patent Document 1 where the inner second orifice is substantially one round. FIG. 6 shows damping characteristics when a vibration is applied in a frequency region corresponding to idling vibration by applying vibration with an amplitude of plus / minus 0.05 mm with respect to a conventional device (conventional example) that is (single). .

Table 1 below shows the outer orifice (first orifice) and the inner orifice (second orifice) for the apparatus (example) and the conventional apparatus (conventional example 1 and conventional example 2) that obtain the attenuation characteristics shown in FIG. The cross-sectional area (S1) (S2) of the orifice), the orifice length (L1) (L2), and the value obtained by multiplying the cross-sectional area by the orifice length (corresponding to the volume) (m1) (m2) are shown respectively. . Although the attenuation characteristic of the conventional example (B) line in FIG. 4 is based on the conventional example 1, the attenuation characteristic of the conventional example 2 is almost the same.

Table 2 below shows the ratio (m2 / m1) of the values (m1) and (m2) corresponding to the volume for the example device and the conventional device (conventional example 1 and conventional example 2) of Table 1 above. , The ratio (L2 / L1) of the orifice lengths (L1) and (L2), and the square root of the ratio between the sectional area and the orifice length related to the equation for obtaining the resonance frequency, respectively.

  From Table 1 and Table 2 above, the damping characteristic of the embodiment (A) line in FIG. 4, that is, particularly in the low frequency range from about 5 Hz to about 20 Hz corresponding to the engine rotation 0.5 order vibration. In order to obtain effective characteristics, the ratio (m2 / m1) of the value corresponding to the volume for both the inner and outer orifices is 2.0 or more, and the ratio of the orifice length (L2 / L1) is 1. Further, it is required to design such that the square root of the ratio of the cross-sectional area to the orifice length is 0.45 or less. In other words, by setting the inner and outer two orifices in this way, it is possible to enhance the damping and suppressing effect on the vibration in the low frequency range. For this reason, it can be said that it is a particularly effective countermeasure to meet the above-mentioned requirement to lengthen the orifice length of the inner second orifice as a double winding form as in the present invention.

It is a longitudinal cross-sectional view of the whole liquid enclosure type vibration isolator of the Example of this invention. FIG. 2 is a partial cross-sectional view of FIG. It is a plane (bottom) figure from the lower surface side of the orifice formation member and liquid chamber formation member which comprise a partition structure part. It is a characteristic line figure (graph) which shows the damping characteristic with respect to the idling vibration including the engine rotation 0.5 order vibration of the liquid enclosure type vibration isolator which concerns on the Example of this invention, and the conventional apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st connection member 2 2nd connection member 3 Insulator 4 1st diaphragm 5 Main chamber 6 Sub chamber 7 1st orifice (1st orifice)
8 Third liquid chamber 9 Second orifice (second orifice)
9a, 9b Inner / outer passage 10 Partition component 11 Orifice forming member 12 Liquid chamber forming member 13 Partition receiving plate 24 Cylindrical portion 33 Rubber portion 41 Auxiliary metal fitting 71 Communication port 72 Notch portion 91 Opening portion 92 Folding portion 93 Partition wall 94 Inner partition wall 131 Communication port 132 Opening hole

Claims (2)

A first connecting member attached to the vibrating body, a second connecting member attached to a member on the vehicle body side, and a vibration between the first connecting member and the second connecting member between the first connecting member and the second connecting member. And a rubber-like insulator to be cut off, a first diaphragm facing the insulator at an interval in the axial direction, and a wall of the chamber between the insulator and the first diaphragm at a part of the insulator. A main chamber that is formed and in which a liquid is sealed, and a sub chamber that is communicated with the main chamber via a first orifice and in which a part of the chamber wall is formed by the first diaphragm; A partition component for partitioning the main chamber and the sub chamber, and a third liquid chamber in the partition component, wherein a part of the chamber wall is partitioned by a second diaphragm with respect to the main chamber And the third liquid chamber and the front Comprising a second orifice communicating between the auxiliary chamber, in the type of liquid-filled vibration damping device having two orifices,
The second orifice is provided outside the third liquid chamber in the partition component and has an annular double winding shape in plan view, and the first orifice is outside the second orifice. Is formed in a circular arc shape in plan view formed by a part of the ring, the orifice length of the second orifice is formed longer than the orifice length of the first orifice, A liquid filled type vibration damping device, wherein the opening hole on the sub chamber side of the second orifice has a smaller opening area than the communication port on the sub chamber side of the first orifice . 2. The liquid-filled vibration isolator according to claim 1, wherein a cross-sectional area of the first orifice is smaller than a cross-sectional area of the second orifice .

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