JP2004278701A - Vibration isolation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vibration isolation device for absorbing energy at the time of impact with small displacement magnitude of a supported member, and for effectively damping vibrations of a vibration source side. <P>SOLUTION: The vibration isolation device 10 has a first elastic member 16 and a second elastic member 20 connected in series in a direction where force acts on the supported member to the supported member. The first elastic member 16 or the second elastic member 20 supports the supported member, while one of the first elastic member 16 and the second elastic member 20 is under a predetermined load. A spring constant of the elastic member 16 as one elastic member under the predetermined load is smaller than a spring constant of the other elastic member under the predetermined load . <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an anti-vibration device used for, for example, an engine mount.
[0002]
[Prior art]
As shown in FIG. 11, in a vibration isolator 100 used for a conventional engine mount, a first rubber member (spring constant K1) 104 is disposed inside a cylindrical member 102. The first rubber member 104 has a support portion 106 for supporting a heavy object such as an engine (not shown). On the other hand, inside the cylindrical member 102, a second rubber member (spring constant K2) 108 that is arranged separately from the first rubber member 108 is arranged. The minimum separation distance between the first rubber member 104 and the second rubber member 108 is set to a. The mechanical characteristics of the vibration isolator 100 are as shown in FIG.
[0003]
Here, the vehicle runs with the engine attached to the vibration isolator 100. In this state, as shown in FIG. 12A, the engine is supported by the first rubber member 104 having a spring constant K1.
Then, when an impact force acts due to an accident or the like during the traveling, the first rubber member 104 moves the minimum separation distance a due to the inertia force of the engine and comes into contact with the second rubber member 108. In this state, as shown in FIG. 12A, the engine is supported by a first rubber member 104 having a spring constant K1 and a second rubber member 108 (combined spring constant K1 + K2) having a spring constant K2. Has become. Therefore, as shown in FIG. 12B, the spring constant sharply increases.
[0004]
According to the conventional vibration isolator 100, the first rubber member 104 moves and comes into contact with the second rubber member 108 from the moment when a load is applied to the first rubber member 104. , The displacement of the engine is increased. As a result, there is a problem that the engine is easily damaged.
[0005]
On the other hand, if the spring constant sharply increases at the time of impact, there is a problem that vibration transmitted from the vehicle body to the engine cannot be attenuated effectively.
[0006]
[Patent Document 1]
JP-A-6-270988
[0007]
[Problems to be solved by the invention]
Therefore, the present invention has been made in view of the above circumstances, and it is possible to absorb energy at the time of impact with a small displacement amount of a supported member, and to effectively attenuate vibration on the vibration source side. It is an object of the present invention to provide an anti-vibration device capable of performing the following.
[0008]
[Means for Solving the Problems]
The present invention employs the following means in order to solve the above problems.
The invention according to claim 1 is a vibration isolator that connects the supported member to the vibration source side and attenuates the vibration transmitted from the vibration source side to the supported member. A first elastic member and a second elastic member connected in series in a direction in which a force is applied to the supporting member and the supported member moves, wherein the first elastic member or the second elastic member The supported member is supported by the first elastic member or the second elastic member in a state in which a predetermined load is applied to one of the elastic members, and the one elastic member at the time of the predetermined load The spring constant is smaller than the spring constant of the other elastic member when the predetermined load is applied.
[0009]
According to the first aspect of the invention, when a force is applied from the vibration source side, the supported member moves by its inertial force. At this time, the other elastic member to which a predetermined load has not been applied is elastically deformed. Here, since a predetermined load is applied to one elastic member in advance, if the inertial force of the supported member is equal to or less than the predetermined load, the one elastic member does not elastically deform. For this reason, the supported member only needs to move the elastic deformation amount of the other elastic member, and the displacement amount of the supported member can be made relatively small.
Further, when the inertial force of the supported member becomes larger than the predetermined load, one of the elastic members to which the predetermined load is applied in advance is also elastically deformed. At this time, the displacement of the supported member is increased by the amount of elastic deformation of one elastic member.
As described above, in the present invention, since a predetermined load is applied to one of the elastic members in advance, the amount of movement (displacement) of the one elastic member is smaller than that in a case where the predetermined load is not applied in advance. Becomes smaller. That is, since the elastic member does not receive a high load to absorb the force input to the supported member, breakage of each elastic member can be prevented. As a result, breakage of the supported member supported by these elastic members can be prevented.
In particular, in the present invention, since a relatively small amplitude vibration can be cut off by not applying a predetermined load to the other elastic member in advance, the supported member is set on the premise that the small amplitude vibration is cut off. It is characterized in that it can prevent breakage.
[0010]
According to a second aspect of the present invention, in the vibration damping device according to the first aspect, the one elastic member and the other elastic member are formed of rubber members, and the one elastic member is formed of the other elastic member. The damping performance is set to be higher than that of the member.
[0011]
According to the invention described in claim 2, one of the elastic members and the other elastic member are formed of rubber members, and one of the elastic members has a higher damping performance than the other elastic member. As a result, the vibration from the vibration source is greatly attenuated by the one elastic member, and the swing of the supported member with respect to the vibration source can be effectively attenuated.
In particular, by providing the elastic member on the side on which a predetermined load is applied with high damping, the damping performance of the elastic member in the high load region when the first elastic member and the second elastic member are combined. Can be increased, and the damping effect can be further enhanced.
[0012]
According to a third aspect of the present invention, in the vibration damping device according to the first aspect, the one elastic member is formed of a metal spring, and the other elastic member is formed of a rubber member. .
[0013]
According to the third aspect of the present invention, since one of the elastic members to which a predetermined load is applied in advance is made of a metal spring, the amount of deformation increases, so that the elastic energy of the one elastic member can be increased. . Thereby, the value of the predetermined load applied to the one elastic member can be further increased, and the movement amount of the supported member can be further reduced.
[0014]
According to a fourth aspect of the present invention, in the vibration damping device according to the third aspect, a damper that applies a damping resistance to the supported member that moves by applying a force is provided in parallel with the metal spring. It is characterized by.
[0015]
According to the fourth aspect of the present invention, the damper for applying the damping resistance to the supported member that moves by the force is provided in parallel with the metal spring, so that the supported member swings with respect to the vibration source. Can be effectively attenuated.
[0016]
The invention according to claim 5 is a vibration isolator that connects the supported member to the vibration source side and attenuates the vibration transmitted from the vibration source side to the supported member, wherein the vibration isolator has a cylindrical shape. A first rubber member provided inside the cylindrical member and having a connection portion connecting the supported member; and a first rubber member disposed radially outside the first rubber member. A second rubber member that contacts at least a part of the peripheral surface, a partition member that partitions the first rubber member and the second rubber member and applies a predetermined load to the second rubber member; Wherein the spring constant of the second rubber member at the time of the predetermined load is smaller than the spring constant of the first rubber member at the time of the predetermined load.
[0017]
According to the invention described in claim 5, the supported member is supported by the connection portion of the first rubber member in a state where a predetermined load is applied from the partition member to the second rubber member. Therefore, the second rubber member is not elastically deformed unless the inertial force of the supported member is equal to or larger than the predetermined load. As a result, the movement (displacement) of the supported member is reduced, and damage to the supported member can be prevented, similarly to the first aspect of the invention.
[0018]
According to a sixth aspect of the present invention, in the vibration damping device according to the fifth aspect, the second rubber member is set to have a higher damping performance than the first rubber member. It is characterized by.
[0019]
According to the invention as set forth in claim 6, since the second rubber member is set to have a higher damping performance than the first rubber member, vibration from the vibration source is reduced by the second rubber member. The vibration is largely attenuated by the member, and the swing of the supported member with respect to the vibration source side can be effectively attenuated.
In particular, by providing the rubber member on the side on which the predetermined load is applied with high damping, the damping performance of the rubber member in the high load region when the first rubber member and the second rubber member are combined. Can be increased, and the damping effect can be further enhanced.
[0020]
The invention according to claim 7 is a vibration isolator that connects the supported member to the vibration source side and attenuates the vibration transmitted from the vibration source side to the supported member, wherein the vibration isolation device has a cylindrical shape. A first rubber member provided inside the cylindrical member and having a connection portion connecting the supported member; and a first rubber member disposed radially outside the first rubber member. A second rubber member that contacts at least a part of the peripheral surface, a partition member that partitions the first rubber member and the second rubber member and applies a predetermined load to the first rubber member; Wherein the spring constant of the first rubber member at the time of the predetermined load is smaller than the spring constant of the second rubber member at the time of the predetermined load.
[0021]
According to the invention described in claim 7, the supported member is supported by the connection portion of the first rubber member in a state where a predetermined load is applied from the partition member to the first rubber member. Therefore, the first rubber member is not elastically deformed unless the inertial force of the supported member becomes equal to or larger than the predetermined load. As a result, the movement (displacement) of the supported member is reduced, and damage to the supported member can be prevented, similarly to the first aspect of the invention.
[0022]
According to an eighth aspect of the present invention, in the vibration damping device according to the seventh aspect, the first rubber member is set to have a higher damping performance than the second rubber member. It is characterized by.
[0023]
According to the eighth aspect of the present invention, since the first rubber member is set to have a higher damping performance than the second rubber member, the vibration from the vibration source is reduced by the first rubber member. The vibration is largely attenuated by the member, and the swing of the supported member with respect to the vibration source side can be effectively attenuated.
In particular, by providing the rubber member on the side on which the predetermined load is applied with high damping, the damping performance of the rubber member in the high load region when the first rubber member and the second rubber member are combined. Can be increased, and the damping effect can be further enhanced.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an anti-vibration device according to a first embodiment of the present invention will be described with reference to the drawings. The anti-vibration device of the present embodiment is used, for example, when connecting an expensive conveyed product that is loaded on an automobile or the like and requires anti-vibration performance to a vehicle body.
[0025]
As shown in FIG. 1, the vibration isolator 10 of the present embodiment includes a storage member 12. The opening edge 14 of the storage member 12 is formed by being bent radially inward.
Inside the housing member 12, a first rubber member 16 is fixed to the bottom surface of the housing member 12 by a fixing means such as an adhesive. A disk-shaped first metal plate 18 is bonded and fixed to an end surface of the first rubber member 16 opposite to the bonding surface. The outer diameter of the first metal plate 18 is set to be larger than the inner diameter of the opening edge 14 of the storage member 12.
[0026]
A second rubber member 20 is bonded and fixed to the first metal plate 18. A second metal plate 22 is bonded and fixed to an end surface of the second rubber member 20. A protrusion 24 is formed on the second metal plate 22, and the protrusion 24 supports a conveyed object 26. The outer diameter of the second metal plate 22 is set to be smaller than the inner diameter of the opening edge 14 of the storage member 12.
[0027]
Here, features of the present invention will be described in detail.
[0028]
In this anti-vibration device 10, a state in which the first metal plate 18 has received pressure from the opening edge 14 of the storage member 12 in the direction of arrow A in FIG. 1 in order to apply a predetermined load to the first rubber member 16 in advance. And is stored inside the storage member 12. That is, the first rubber member 16 is housed in the housing member 12 in a state where a predetermined compressive load (hereinafter, appropriately referred to as “initial load”) is applied.
[0029]
The spring constant of the first rubber member 16 at the time of the initial load is set to be smaller than the spring constant of the second rubber member 20 at the time of the initial load being applied to the second rubber member 20.
[0030]
Further, the first rubber member 16 is configured to have a higher damping performance than the second rubber member 20. For example, the first rubber member 16 is manufactured by combining and molding a group of rubbers located in a region of high attenuation and high dynamic magnification when the vertical axis represents attenuation and the horizontal axis represents dynamic magnification. On the other hand, the second rubber member 20 is formed by combining and forming a rubber group located in a region where low attenuation and low dynamic magnification are shown when the vertical axis represents attenuation and the horizontal axis represents dynamic magnification. Manufacturing.
[0031]
In addition, the vibration isolator 10 of the present embodiment is arranged such that the first rubber member 16 and the second rubber member 20 are arranged in series along the transport direction of the transported object 26 (the direction of arrow G in FIG. 1). Have been. Also, a plurality of the vibration isolators 10 of the present embodiment are mounted on the automobile 28, and one of the vibration isolators 10 supports the front end of the conveyed object 26, and the other of the vibration isolators 10 is behind the conveyed object 26 The transport object 26 is supported by supporting the end portion.
[0032]
Next, the operation and effect of the vibration isolator 10 of the present embodiment will be described.
[0033]
As shown in FIG. 1, when the automobile 28 is running and sudden braking is applied, a force is applied to the first rubber member 16 in the direction of arrow A in FIG.
[0034]
Here, the mechanical characteristics of the rubber member to which no compressive load has been previously applied are as shown in FIG. 2A, and the rubber member elastically deforms and bends even when a small load is applied. Since a predetermined compressive load (initial load) is applied to the rubber member 16 in advance, its mechanical characteristics are as shown in FIG. That is, as shown in FIG. 2B, even if a force equal to or less than the pre-loaded load acts on the first rubber member 16, the first rubber member 16 does not elastically deform. For this reason, for example, when the automobile 28 suddenly applies a brake, the transported object 26 moves along the traveling direction of the automobile (the direction of the arrow A in FIG. 1) due to its inertial force. At this time, the second rubber member 20 has been compressed and deformed by the inertial force of the conveyed object 26.
[0035]
Next, when the inertial force of the transported object 26 becomes larger than the initial load, the first rubber member 16 is compressed and deformed. When the first rubber member 16 is compressed and deformed, the conveyed object 26 further moves in the traveling direction (the direction of the arrow G in FIG. 1) by the amount of the substantially compressed deformation of the first rubber member 16.
[0036]
As described above, in the vibration isolator 10 of the present invention, since the first rubber member 16 is pre-loaded with the predetermined load, the first rubber member 16 is compared with the case where the predetermined load is not pre-loaded, and The amount of movement (displacement) of the rubber member 16 can be reduced. Thus, the input force can be absorbed without increasing the load applied to the first rubber member 16 and the second rubber member 20.
[0037]
Here, the effect will be described with reference to the graphs shown in FIGS.
That is, the conveyed object 26 is a dynamic material in which the first rubber member 16 having the mechanical characteristics shown in FIG. 2B and the second rubber member 20 having the mechanical characteristics shown in FIG. It is supported by the synthetic rubber member having the characteristic (see FIG. 3). As shown in FIG. 3, an initial load is applied in advance by combining the first rubber member 16 to which a predetermined load is applied in advance and the second rubber member 20 to which a predetermined load is not applied in advance. The elastic coefficient in the high load region can be reduced as compared with the case where the unconnected rubber members are simply connected in series (see arrow B in FIG. 3). For this reason, a predetermined potential energy (illustrated by S in FIG. 3) can be stored without applying a high load, so that the first rubber member 16 and the second rubber member 20 are prevented from being damaged. Therefore, it is possible to prevent the transported object 26 supported by these members from being damaged.
[0038]
In addition, by not applying a predetermined load to the second rubber member 20 in advance, it is possible to cut off a vibration having a relatively small amplitude and a low attenuation leading to a sound. As described above, in the vibration isolator 10 of the present invention, on the assumption that vibration having relatively small amplitude and low attenuation leading to sound is cut off, the force input by the short stroke of the first rubber member 16 is further applied. Can be absorbed, and breakage of the transported object 26 can be prevented.
[0039]
Further, as shown in FIG. 1, by arranging the vibration isolator 10 of the present embodiment so as to support the rear end face of the conveyed object 26, the inertia force of the conveyed object 26 decreases in the direction of arrow C in FIG. 1. Even when it works, the same effect can be obtained.
Further, in particular, by providing the first rubber member 16 on the side where a predetermined load is applied to have a high damping property, the first rubber member 16 and the second rubber member 20 can have a high damping property. The damping performance of the rubber member in the load region can be further increased, and the vibration damping effect can be further enhanced.
[0040]
Further, for example, as shown in FIG. 4, the anti-vibration device 10 of the present embodiment may be disposed on the sub-frame 30 and used to support the engine 32 in anti-vibration. As described above, by applying the vibration isolator 10 as an engine mount, the displacement of the engine 32 at the time of impact can be reduced, and the vibration transmitted to the engine 32 can be effectively attenuated.
[0041]
Next, an anti-vibration device according to a second embodiment of the present invention will be described with reference to the drawings. The vibration isolator of the present embodiment is used, for example, when connecting an expensive conveyed product that is loaded on an automobile or the like and requires a damping property to the vehicle body, similarly to the vibration isolator of the first embodiment. The same components as those of the vibration isolator according to the first embodiment are denoted by the same reference numerals, and description thereof will not be repeated.
[0042]
As shown in FIG. 5A, the vibration isolator 50 of the present embodiment includes a mounting member 52 having an L-shaped cross section. A through-hole 54 is formed in the end piece 52A of the mounting member 52, and a moving member 56 having a rod-shaped outer periphery formed with a thread groove (not shown) is inserted into the through-hole 54. At one end of the moving member 56, an enlarged diameter portion 56A having a larger diameter is formed. A nut 57 is screwed into the other end.
[0043]
A first metal plate 58 is mounted inside the enlarged diameter portion 56 </ b> A on the other end side of the moving member 56. A coil spring 60 is mounted on the outer periphery of the moving member 56, and the coil spring 60 is located between the first metal plate 58 and the end piece 52 </ b> A of the mounting member 52. Both ends of the coil spring 60 are in contact with the first metal plate 58 and the end piece 52A of the mounting member 52, respectively.
[0044]
One end surface of the rubber member 62 is bonded and fixed to the enlarged diameter portion 56A on one end side of the moving member 56 and the first metal plate 58. A second metal plate 64 is adhesively fixed to the other surface of the rubber member 62. Thus, the rubber member 62 is located between the first metal plate 58 and the second metal plate 64.
[0045]
Further, a protrusion 66 is formed on the second metal plate 64, and the protrusion 66 supports the front end of the transported object 26.
[0046]
Here, features of the present invention will be described in detail.
[0047]
In the vibration isolator 50, the screwing position of the nut portion 57 is adjusted in order to apply a predetermined load (hereinafter, appropriately referred to as “initial load”) to the coil spring 60 in advance, and the coil spring 60 is fixed to the predetermined position. Is applied. Although not shown in FIG. 5, the rear end of the transported object 26 is also supported by the vibration isolator of the present embodiment.
[0048]
The spring constant of the coil spring 60 at the time of the initial load is set to be smaller than the spring constant of the rubber member 62 when the initial load is applied to the rubber member 62.
[0049]
The vibration isolator 50 of the present embodiment is arranged such that the coil spring 60 and the rubber member 62 are arranged in series along the transport direction of the transported object 26 (the direction of arrow G in FIG. 5).
[0050]
Next, the operation and effect of the vibration isolator 50 of the present embodiment will be described.
[0051]
As shown in FIG. 5A, when the automobile 28 is running and sudden braking is applied, a force is applied to the coil spring 60 in the direction of arrow D in FIG.
[0052]
Here, since a predetermined compression load (initial load) is applied to the coil spring 60 in advance, the coil spring 60 is not elastically deformed even if a force equal to or less than the previously applied load acts on the coil spring 60. Therefore, for example, when the automobile 28 suddenly applies a brake, the transported object 26 moves in the traveling direction of the automobile (the direction of the arrow D in FIG. 5A) due to its inertial force. At this time, the rubber member 62 has been compressed and deformed by the inertial force of the transported object 26.
[0053]
Next, as shown in FIG. 5B, when the inertial force of the transferred object 26 becomes larger than the initial load, the moving member 56 moves in the traveling direction (the direction of arrow G in FIG. 5), and the coil spring 60 further moves. Compression deformation. When the coil spring 60 is further compressed and deformed, the conveyed object 26 is further moved in the traveling direction (the direction of arrow G in FIG. 5) by the amount of the substantially compressed deformation of the coil spring 60.
[0054]
As described above, in the vibration isolator 50 of the present invention, since the coil spring 60 is pre-loaded with the predetermined load, the movement of the coil spring 60 (compared to the case where the predetermined load is not pre-loaded). Displacement) amount can be reduced. Thus, the input force can be absorbed without increasing the load applied to the coil spring 60.
[0055]
Here, the effect will be described with reference to a graph shown in FIG.
That is, the conveyed object 26 is supported by the synthetic rubber member having the mechanical characteristics shown in FIG. As shown in FIG. 6, by combining the coil spring 60 to which the predetermined load is applied in advance and the rubber member 62 to which the predetermined load is not applied, the rubber members to which the initial load is not applied are combined. The elastic modulus in the high load region can be reduced as compared with the case of simply connecting in series (see arrow E in FIG. 6). For this reason, a predetermined potential energy (illustrated by S in FIG. 6) can be stored without increasing the load, so that the coil spring 60 and the rubber member 62 can be prevented from being damaged. As a result, it is possible to prevent the transported object 26 supported by the coil spring 60 and the rubber member 62 from being damaged.
[0056]
In addition, by not applying a predetermined load to the member 62 in advance, it is possible to cut off vibration having relatively small amplitude and low attenuation leading to sound. As described above, in the vibration isolator 50 of the present invention, on the assumption that the vibration having a relatively small amplitude and low attenuation leading to sound is cut off, the force input with a short stroke of the coil spring 60 is further absorbed. This can prevent the transported object 26 from being damaged.
[0057]
In addition, as in the case of the vibration isolator 50 of the present embodiment, the amount of deformation can be increased by configuring one of the elastic members to which a predetermined load is applied in advance by the coil spring 60, so that the elastic energy can be increased. Can be. This makes it possible to further reduce the amount of movement of the coil spring 60 required to absorb the impact energy, and further reduce the load applied to the coil spring 60 and the rubber member 62 to absorb the impact energy. be able to.
[0058]
Although not shown, the vibration isolator 50 of the present embodiment is disposed so as to support the rear end surface of the conveyed object 26, so that a similar force is exerted even when a force in the direction opposite to the arrow D direction in FIG. The effect can be obtained.
[0059]
As shown in FIG. 7, a viscous damper 70 may be provided in parallel with the coil spring 60. For example, by providing the first metal plate 58 with the piston 71 constituting the viscous damper 70, the vibration of the transported object 26 with respect to the vehicle body can be effectively attenuated by the viscous damper 70.
[0060]
Next, an anti-vibration device according to a third embodiment of the present invention will be described with reference to the drawings. The anti-vibration device according to the present embodiment is used for an engine mount that supports an anti-vibration engine mounted on an automobile, for example.
[0061]
As shown in FIG. 8, the vibration isolator 80 of the present embodiment includes a cylindrical member 82. A projection 84 is formed on the inner periphery of the cylindrical member 82 so as to project radially inward.
[0062]
A central rubber member 86 is disposed at the center of the inside of the cylindrical member 82. The central rubber member 86 is provided with a connecting portion 88 for connecting and supporting a part of an engine (not shown). The center rubber member 86 is provided with a horn 90.
[0063]
Two partition rings 92A and 92B are adhered to the outer periphery of the central rubber member 90. Both ends of these partition rings 92A and 92B are in contact with the protruding portions 84, respectively, and sandwich the central rubber member 90 between the two partition rings 92A and 92B.
[0064]
An outer rubber member 94 is disposed radially outside each of the partition rings 92A and 92B. The outer rubber member 94 is in contact with the inner peripheral surface of the cylindrical member 82. Note that the outer rubber member 94 is also formed with a curb 96.
[0065]
Thus, the vibration isolator 80 of the present embodiment is configured such that the structure is targeted for the straight line L passing through the center point X of the cylindrical member 82.
[0066]
Here, features of the present invention will be described in detail.
[0067]
A predetermined load is applied to the outer rubber member 94 radially outward (in the direction of arrow F in FIG. 8) by the partition rings 92A and 92B, and the outer rubber member 94 is in a state of being compressed and deformed.
[0068]
The spring constant of the outer rubber member 94 at the time of the initial load is set to be smaller than the spring constant of the center rubber member 86 when the initial load is applied to the center rubber member 86.
[0069]
The outer rubber member 94 is set to have a higher damping property than the center rubber member 86.
[0070]
As described above, in the vibration isolator 80 of the present embodiment, the center rubber member 86 and the outer rubber member 94 are arranged in series along the radial outer side (the direction of arrow F in FIG. 8).
[0071]
Next, the operation and effect of the vibration isolator 80 of the present embodiment will be described.
[0072]
As shown in FIG. 8, when the vehicle travels on a bad road or the like, a force acts on the outer rubber member 94 from the vehicle body side inward in the radial direction (the direction of arrow F in FIG. 8).
[0073]
Here, the mechanical characteristics of the outer rubber member 94 to which no compressive load is previously applied are as shown in FIG. 9A, and the outer rubber member 94 is elastically deformed and bent even when a small load is applied. Since a predetermined compressive load (initial load) is applied to the outer rubber member 94 in advance, its mechanical characteristics are as shown in FIG. 9B. That is, as shown in FIG. 9B, even if a force equal to or less than the pre-loaded load acts on the outer rubber member 94, the outer rubber member 94 is not elastically deformed. Therefore, for example, when the automobile 28 suddenly applies a brake, the engine moves in the traveling direction of the automobile (the direction of arrow G in FIG. 8) due to its inertia. At this time, the center side rubber member 86 has been compressed and deformed by the inertial force of the transported object 26.
[0074]
Next, when the inertial force of the engine becomes larger than the initial load, the outer rubber member 94 is compressed and deformed. When the outer rubber member 94 is compressed and deformed, the engine further moves in the traveling direction (the direction of the arrow G in FIG. 8) by the amount of substantially compressed deformation of the outer rubber member 94.
[0075]
As described above, in the anti-vibration device 80 of the present invention, since the predetermined load is applied to the outer rubber member 94 in advance, the outer rubber member 94 is compared with the case where the predetermined load is not applied in advance. The amount of movement (displacement) can be reduced. Thus, the input force can be absorbed without increasing the load applied to the outer rubber member 94 and the center rubber member 86.
[0076]
Here, the above effects will be described with reference to FIGS.
Further, the transported object 26 has a mechanical characteristic (FIG. 9B) in which the outer rubber member 94 having the mechanical characteristic shown in FIG. 9B and the center rubber member 86 having the mechanical characteristic shown in FIG. 10) is supported by the synthetic rubber member. Here, as shown in FIG. 10, an initial load is applied in advance by combining the outer rubber member 94 to which a predetermined load is applied in advance and the center rubber member 96 to which a predetermined load is not applied in advance. The elastic coefficient in the high load region can be reduced as compared with the case where the unconnected rubber members are simply connected in series (see arrow H in FIG. 10). For this reason, a predetermined potential energy (illustrated by S in FIG. 10) can be stored without increasing the load, so that the outer rubber member 94 and the center rubber member 86 can be prevented from being damaged. As a result, it is possible to prevent the transported articles 26 supported by them from being damaged.
[0077]
Further, by not applying a predetermined load to the center rubber member 86 in advance, it is possible to cut off a vibration having a relatively small amplitude and a low attenuation leading to a sound. As described above, in the vibration isolator 80 of the present invention, on the assumption that the vibration having relatively small amplitude and low attenuation leading to sound is cut off, the force input by the short stroke of the outer rubber member 94 is further absorbed. It is also possible to prevent the transported object 26 from being damaged.
[0078]
Further, in particular, by providing the outer rubber member 94 on the side where a predetermined load is applied to have a high damping property, when the outer rubber member 94 and the center rubber member 86 are combined, each of the rubbers in the high load region is formed. The damping performance of the member can be further enhanced, and the vibration damping effect can be further enhanced.
[0079]
Note that, unlike the configuration of the vibration isolator 80 of the third embodiment, a configuration in which an initial load is applied to the central rubber member 86 from each of the partition rings 92A and 92B in an initial state may be used. At this time, no initial load is applied to the outer rubber member 94. According to the vibration damping device having such a configuration, when a force acts on the engine side, the amount of displacement of the center rubber member 86 at the time of impact can be reduced, and similarly, damage to the engine and the like can be effectively prevented. can do.
[0080]
In each of the above embodiments, the case where the present invention is used for a conveyed object mounted on an automobile such as an engine mount has been described as a specific example, but the present invention is not limited to these. For example, the present invention can be applied to a vibration isolator used for a suspension or the like.
[0081]
【The invention's effect】
The anti-vibration device of the present invention described above has the following effects.
According to the first aspect of the present invention, since the predetermined load is applied to the one elastic member in advance, the amount of movement (displacement) of the one elastic member is compared with the case where the predetermined load is not applied in advance. Becomes smaller. That is, since the elastic member does not receive a high load to absorb the force input to the supported member, breakage of each elastic member can be prevented. As a result, breakage of the supported member supported by these elastic members can be prevented.
In particular, in the present invention, since a relatively small amplitude vibration can be cut off by not applying a predetermined load to the other elastic member in advance, the supported member is set on the premise that the small amplitude vibration is cut off. It is characterized in that it can prevent breakage.
[0082]
According to a second aspect of the present invention, one of the elastic members and the other elastic member are formed of rubber members, and one of the elastic members is set to have higher damping performance than the other elastic member. Therefore, the vibration from the vibration source is greatly attenuated by the one elastic member, and the swing of the supported member with respect to the vibration source can be effectively attenuated.
In particular, by providing the elastic member on the side on which a predetermined load is applied with high damping, the damping performance of the elastic member in the high load region when the first elastic member and the second elastic member are combined. Can be increased, and the damping effect can be further enhanced.
[0083]
According to the third aspect of the present invention, since one of the elastic members to which a predetermined load is applied in advance is formed of a metal spring, the amount of deformation is increased, so that the elastic energy of the one elastic member can be increased. Thereby, the value of the predetermined load applied to the one elastic member can be further increased, and the movement amount of the supported member can be further reduced.
[0084]
According to the fourth aspect of the present invention, a damper for applying a damping resistance to a supported member that moves by the action of a force is provided in parallel with the metal spring, so that the supported member can be effectively shaken with respect to the vibration source. Can be attenuated.
[0085]
In the invention described in claim 5, the supported member is supported by the connection portion of the first rubber member in a state where a predetermined load is applied from the partition member to the second rubber member. Therefore, the second rubber member is not elastically deformed unless the inertial force of the supported member is equal to or larger than the predetermined load. As a result, the movement (displacement) of the supported member is reduced, and damage to the supported member can be prevented, similarly to the first aspect of the invention.
[0086]
In the invention according to claim 6, since the second rubber member is set so as to have a higher damping performance than the first rubber member, the vibration from the vibration source is larger than the second rubber member. The vibration of the supported member with respect to the vibration source can be effectively attenuated.
In particular, by providing the rubber member on the side on which the predetermined load is applied with high damping, the damping performance of the rubber member in the high load region when the first rubber member and the second rubber member are combined. Can be increased, and the damping effect can be further enhanced.
[0087]
In the invention according to claim 7, the supported member is supported by the connection portion of the first rubber member in a state where a predetermined load is applied from the partition member to the first rubber member. Therefore, the first rubber member is not elastically deformed unless the inertial force of the supported member becomes equal to or larger than the predetermined load. As a result, the movement (displacement) of the supported member is reduced, and damage to the supported member can be prevented, similarly to the first aspect of the invention.
[0088]
In the invention according to claim 8, since the first rubber member is set to have a higher damping performance than the second rubber member, the vibration from the vibration source is larger than the first rubber member. The vibration of the supported member with respect to the vibration source can be effectively attenuated.
In particular, by providing the rubber member on the side on which the predetermined load is applied with high damping, the damping performance of the rubber member in the high load region when the first rubber member and the second rubber member are combined. Can be increased, and the damping effect can be further enhanced.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an example in which a vibration isolator according to a first embodiment of the present invention is applied as a device that supports a conveyed object.
FIG. 2A is a graph showing mechanical characteristics when an initial load is not applied to a rubber member constituting the vibration isolator of the first embodiment, and FIG. 2B is a graph showing the mechanical characteristics of the first embodiment. It is a graph which shows the mechanical characteristic at the time of initial load being applied to the rubber member which comprises a vibration device.
FIG. 3 shows mechanical characteristics when a first rubber member to which an initial load is applied and a second rubber member to which no initial load is applied are combined, which constitute the vibration isolator of the first embodiment. It is a graph.
FIG. 4 is a diagram showing an example in which the vibration damping device according to the first embodiment of the present invention is applied as an engine mount.
FIG. 5 is a schematic configuration diagram of a vibration isolator according to a second embodiment of the present invention.
FIG. 6 is a graph showing mechanical characteristics when a coil spring to which an initial load is applied and a rubber member to which an initial load is not applied are combined, which constitute the vibration isolator of the second embodiment.
FIG. 7 is a configuration diagram showing a modification of the vibration isolator according to the second embodiment of the present invention.
FIG. 8 is a sectional view of a vibration isolator according to a third embodiment of the present invention.
FIG. 9A is a graph showing mechanical characteristics when an initial load is not applied to an outer rubber member constituting the vibration isolator of the third embodiment, and FIG. 9B is a graph showing the mechanical characteristics of the third embodiment. It is a graph which shows the mechanical characteristic at the time of initial load being applied to the outer rubber member which comprises a vibration isolator.
FIG. 10 is a graph showing mechanical characteristics when an outer rubber member to which an initial load is applied and a central rubber member to which an initial load is not applied are combined, which constitute the vibration damping device of the third embodiment. .
FIG. 11 is a sectional view of a conventional vibration isolator.
12A is a mechanical model diagram of the vibration isolator shown in FIG. 11, and FIG. 12B is a graph showing mechanical characteristics of the vibration isolator shown in FIG.
[Explanation of symbols]
10, 50, 80 Anti-vibration device
16 First rubber member (one elastic member, rubber member)
20 Second rubber member (the other elastic member, rubber member)
60 coil spring (metal spring, one elastic member)
62 rubber member (the other elastic member)
70 viscous damper (damper)
82 cylindrical member
86 center rubber member (first rubber member)
92A Compartment ring (compartment member)
92B Compartment ring (compartment member)
94 Outer rubber member (second rubber member)

Claims (8)

In a vibration isolator that connects a supported member to the vibration source side and attenuates vibration transmitted from the vibration source side to the supported member,
The vibration isolator has a first elastic member and a second elastic member connected in series in a direction in which a force acts on the supported member and the supported member moves, and the first elastic member is connected to the first elastic member. Supporting the supported member by the first elastic member or the second elastic member in a state where a predetermined load is applied to one of the elastic members or the second elastic member;
A vibration isolator, wherein a spring constant of the one elastic member at the time of the predetermined load is smaller than a spring constant of the other elastic member at the time of the predetermined load. The one elastic member and the other elastic member are made of a rubber member, and the one elastic member is set to have higher damping performance than the other elastic member. The anti-vibration device according to claim 1. The vibration isolator according to claim 1, wherein the one elastic member is formed of a metal spring, and the other elastic member is formed of a rubber member. The vibration damping device according to claim 3, wherein a damper that applies a damping resistance to the supported member that moves by the action of a force is provided in parallel with the metal spring. In a vibration isolator that connects a supported member to the vibration source side and attenuates vibration transmitted from the vibration source side to the supported member,
The vibration isolator includes a cylindrical member, a first rubber member provided inside the cylindrical member and having a connection portion that connects the supported member, and a first rubber member that is radially outside of the first rubber member. A second rubber member disposed and in contact with at least a part of an inner peripheral surface of the cylindrical member; and a first rubber member and the second rubber member partitioned to form a predetermined rubber member on the second rubber member. And a partition member for applying a load,
A vibration isolator, wherein a spring constant of the second rubber member under the predetermined load is smaller than a spring constant of the first rubber member under the predetermined load. The vibration damping device according to claim 5, wherein the second rubber member is set to have a higher damping performance than the first rubber member. In a vibration isolator that connects a supported member to the vibration source side and attenuates vibration transmitted from the vibration source side to the supported member,
The vibration isolator includes a cylindrical member, a first rubber member provided inside the cylindrical member and having a connection portion that connects the supported member, and a first rubber member that is radially outside of the first rubber member. A second rubber member disposed and in contact with at least a part of an inner peripheral surface of the cylindrical member; and a first rubber member and a second rubber member that are partitioned into a predetermined shape. And a partition member for applying a load,
A vibration isolator, wherein a spring constant of the first rubber member at the time of the predetermined load is smaller than a spring constant of the second rubber member at the time of the predetermined load. The vibration damping device according to claim 7, wherein the first rubber member is set to have a higher damping performance than the second rubber member.

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