JP2014047822A - Vibration isolator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibration isolator capable of obtaining sufficient vibration control effects in both vertical and horizontal directions.SOLUTION: A vibration isolator 5 arranged between a first member 1 and a second member 3 to be vibration-controlled is constituted of a first rubber member 6, a second rubber member 7 and a support member 9. The first rubber member 6 is a rubber material whose elastic constant is larger than that of the second rubber member 7, and the vibration isolator 5 is configured by joining the first rubber member 6 and the second rubber member 7 in series between the first member 1 and the second member 3. A junction portion between the first rubber member 6 and the second rubber member 7 is configured as a rugged engagement part 8 with a rugged shape. Consequently, the vibration isolator 5 can descend a resonance point, obtain a high vibration control effect on the high frequency side and obtain sufficient vibration control effects in both the vertical and horizontal directions.

Description

  The present invention relates to a vibration isolator suitably used for a compressor or the like.

  For suspension systems such as automobiles, the air suspension provided on the left and right front wheels and the left and right rear wheels are expanded and contracted using compressed air discharged from the compressor, thereby changing the weight of the vehicle, the driver 2. Description of the Related Art An air suspension device that can adjust the vehicle height appropriately according to the preference of the vehicle is known. This air suspension device is provided with a vibration isolator that suppresses transmission of vibrations during operation of the compressor to the vehicle body.

  The conventional vibration isolator provided in this air suspension device suppresses transmission of vibration from a vibration source such as a compressor to the vehicle body by installing a rubber member or a coil spring between the compressor and the vehicle body. ing.

  Here, in order to obtain an anti-vibration effect in the vibration frequency band during the operation of the compressor, it is preferable to use an anti-vibration rubber having a resonance point in a frequency band lower than the vibration frequency band. This can be realized by lowering the rubber hardness of the vibration-proof rubber (using soft rubber) or by processing the vibration-proof rubber into a complicated shape. However, since soft rubber has low durability, it is actually necessary to use a vibration-proof rubber having high (hard) rubber hardness in consideration of durability. In addition, processing the vibration-proof rubber into a complicated shape is troublesome and increases the cost.

  In addition, it is conceivable to use a coil spring having high vibration isolation performance and durability as the vibration isolation device. However, since the coil spring cannot attenuate the vibration on the compressor side, there is a problem that the vibration is transmitted to a pipe connected to the compressor and the pipe is likely to deteriorate.

  Thus, Patent Document 1 discloses a vibration isolator that achieves both high vibration isolation performance and durability by connecting a cylindrical rubber member and a coil spring in series.

JP 2008-106927 A

  By the way, with the prior art according to Patent Document 1, it is possible to obtain an anti-vibration effect with respect to vibrations in the upward and downward directions. There is a problem that a vibration effect cannot be obtained.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a vibration isolator capable of obtaining a sufficient anti-vibration effect in both the upward, downward and horizontal directions. It is in.

  In order to solve the above-described problem, the present invention provides a vibration isolator disposed between a first member and a second member to be damped, and is a cylindrical first member attached on one side to the first member. 1 rubber member, and a cylindrical second rubber member having one side attached to the second member and having a different elastic constant from the first rubber member, the first rubber member and the second rubber Each of the other sides of the member has an uneven fitting portion, and a support member is inserted through the axial center side of the first rubber member and the second rubber member.

  According to the present invention, a sufficient anti-vibration effect can be obtained in both the upward, downward, and horizontal directions.

It is the schematic which provided the vibration isolator by the 1st Embodiment of this invention between the 1st member and the 2nd member. It is sectional drawing which shows a vibration isolator alone. It is a physical model figure of a vibration isolator. It is a characteristic diagram which shows the frequency characteristic of the vibration transmissibility of the vibration isolator by a comparative example, and the vibration isolator by 1st Embodiment. It is sectional drawing which shows the vibration isolator by the 2nd Embodiment of this invention alone. It is a physical model figure of a vibration isolator. It is a characteristic diagram which shows the frequency characteristic of the vibration transmissibility of the vibration isolator by a comparative example, and the vibration isolator by 1st, 2nd embodiment. It is sectional drawing which shows the vibration isolator by the modification of this invention alone.

  Hereinafter, a vibration isolator according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  1 to 4 show a first embodiment of the present invention. A first member 1 shown in FIG. 1 is, for example, a compressor for an air suspension device of an automobile, and the compressor can appropriately adjust the vehicle height by supplying and discharging compressed air to an air suspension (not shown). It is. The compressor (first member 1) is provided with, for example, a flat mounting bracket 2. The mounting bracket 2 is provided with a mounting hole 2A penetrating in the thickness direction. A vibration isolator 5 to be described later is attached to the mounting bracket 2 using the mounting hole 2A.

  The second member 3 is, for example, an attachment member provided on the vehicle body side, and the attachment member (second member 3) is provided with an attachment bracket 4 having an attachment hole 4A in the same manner as the attachment bracket 2. An anti-vibration device 5 to be described later is attached to the mounting bracket 4 using the mounting holes 4A.

  Thereby, the first member 1 is attached to the second member 3 via the vibration isolator 5. Here, the first member 1 and the second member 3 are members to be damped with each other. In the case of the present embodiment, the first member 1 out of the first member 1 and the second member 3 is a compressor. The case where the second member 3 is an attachment member on the vehicle body side is illustrated. However, the present invention is not limited to this, and the first member 1 may be an attachment member and the second member 3 may be a compressor.

  Next, the vibration isolator 5 used in this embodiment will be described.

  The vibration isolator 5 disposed between the first member 1 and the second member 3 suppresses transmission of vibrations of the first member 1 that is a vibration source to the second member 3, and the second member. This is to suppress transmission of vibration on the third side to the first member 1. For this reason, as shown in FIG. 3, the vibration isolator 5 is provided in the middle of the vibration transmission path between the first member 1 and the second member 3. As shown in FIG. 2, the vibration isolator 5 includes a first rubber member 6, a second rubber member 7, and a support member 9.

  The first rubber member 6 to which one side of the vibration transmission path is attached to the first member 1 is made of an elastic body such as rubber or synthetic resin, and is formed in a cylindrical shape. The first rubber member 6 is formed, for example, in a cylindrical shape, an elliptical cylindrical shape, a rectangular cylindrical shape, or the like. In this case, in order to disperse stress due to vibration, a cylindrical shape is preferable.

  An upper surface 6A of the first rubber member 6 is formed as a flat plane, and an annular groove 6C is formed on the outer surface 6B of the first rubber member 6, and the first member 1 is provided in the groove 6C. A peripheral portion of the mounting hole 2A of the mounting bracket 2 is fixed in a fitted state. The vertical (upward and downward) and horizontal vibrations of the first member 1 are transmitted to the first rubber member 6 through the groove 6C. For this reason, the groove 6 </ b> C is on one side of the vibration transmission path of the first rubber member 6.

  On the other hand, the lower surface 6D of the first rubber member 6 serves as a fitting surface with the second rubber member 7 and constitutes the other side of the vibration transmission path. A convex portion 6E having a convex cross section is formed at the center of the lower surface 6D. Further, a through hole 6F through which a shaft portion of a bolt 9A described later is inserted passes through the first rubber member 6 in the upward and downward directions.

  The second rubber member 7 whose one side is attached to the second member 3 is made of an elastic body like the first rubber member 6 and is formed in, for example, a cylindrical shape, an elliptical cylindrical shape, a rectangular cylindrical shape, or the like. In this case, in order to disperse stress due to vibration, a cylindrical shape is preferable.

  The second rubber member 7 has a characteristic that the elastic constant is different from that of the first rubber member 6. In the present embodiment, the second rubber member 7 has a smaller elastic constant (elastic modulus) than the first rubber member 6. That is, the second rubber member 7 is configured as a rubber member that is softer than the first rubber member 6.

  The lower surface 7A of the second rubber member 7 is formed as a flat plane. An annular groove portion 7C is formed on the outer surface 7B of the second rubber member 7, and the second member 3 is provided in the groove portion 7C. A peripheral portion of the mounting hole 4A of the mounting bracket 4 is fixed in a fitted state. The vibration in the vertical direction and the horizontal direction of the second member 3 is transmitted to the second rubber member 7 through the groove portion 7C. For this reason, the groove portion 7 </ b> C is on one side of the vibration transmission path of the second rubber member 7.

  On the other hand, the upper surface 7D of the second rubber member 7 serves as a fitting surface with the first rubber member 6 and constitutes the other side of the vibration transmission path. A concave portion 7E having a concave cross section is formed in the central portion of the upper surface 7D, and the concave portion 7E is fitted with the convex portion 6E of the first rubber member 6. And the fitting part of the 1st rubber member 6 and the 2nd rubber member 7 is uneven | corrugated fitting by the lower surface 6D and the convex part 6E of the 1st rubber member 6, and the upper surface 7D and the recessed part 7E of the 2nd rubber member 7. The first rubber member 6 and the second rubber member 7 are integrated as a unit by being abutted and bonded or welded at the concave and convex fitting portion 8 without a gap.

  As described above, the vibration isolator 5 has a structure in which the first rubber member 6 and the second rubber member 7 are stacked in the upward and downward directions between the first member 1 and the second member 3. That is, the first rubber member 6 and the second rubber member 7 are connected in series to the vibration transmission path between the first member 1 and the second member 3. Further, on the axial center side of the second rubber member 7, a through hole 7F through which a shaft portion of a bolt 9A described later is inserted coaxially with the through hole 6F of the first rubber member 6 penetrates upward and downward. .

  The support member 9 inserted through the through hole 6 </ b> F of the first rubber member 6 and the through hole 7 </ b> F of the second rubber member 7 is for restraining the expansion of the first rubber member 6 and the second rubber member 7. The support member 9 includes a bolt 9A, a nut 9B, and washers 9C and 9D.

  As shown in FIG. 2, the support member 9 has a washer 9 </ b> C arranged coaxially with the through hole 6 </ b> F on the upper surface 6 </ b> A of the first rubber member 6, and the washer 9 </ b> D on the lower surface 7 </ b> A of the second rubber member 7. The bolt 9A is inserted into the through hole 7F and the through hole 6F from the second rubber member 7 side and is fixed by the nut 9B while being arranged coaxially with 7F.

  The anti-vibration device 5 according to the present embodiment has the above-described configuration. Next, the anti-vibration function of the anti-vibration device 5 will be described.

  First, when comparing the first rubber member 6 and the second rubber member 7, the first rubber member 6 has a larger elastic modulus than the second rubber member 7. That is, the first rubber member 6 is a harder rubber material than the second rubber member 7, and the second rubber member 7 is a softer rubber material than the first rubber member 6. The vibration isolator 5 has a configuration in which a first rubber member 6 and a second rubber member 7 having different elastic moduli are connected in series between the first member 1 and the second member 3 (see FIG. 3). ). For this reason, the vibration isolator 5 can lower the resonance point (resonance frequency) by the second rubber member 7 having a small elastic modulus while obtaining the vibration isolating effect of the first rubber member 6 having a large elastic modulus.

  In order to examine such an anti-vibration effect, the frequency acting from the excitation side (for example, the first member 1 made of a compressor) is applied to the anti-vibration device 5 according to the present embodiment and the anti-vibration device according to the comparative example. The relationship with vibration transmissibility was analyzed. The result is shown in FIG. In FIG. 4, the horizontal axis indicates the frequency associated with the vibration when the compressor (first member 1) is operated, and the vertical axis indicates the vibration transmission rate indicating the rate at which the vibration is transmitted to the mounting member (second member 3). Shows the rate. In the figure, when the vibration transmissibility is 1 (100%), the anti-vibration effect is 0%.

  Note that the vibration isolator according to the comparative example is formed by integrating the first rubber member 6 and the second rubber member 7 using a rubber material having the same elastic modulus. FIG. 4 also shows the characteristics of the vibration transmissibility relating to the first rubber member 6 and the second rubber member 7. The vertex A of the characteristic line of the vibration isolator according to the comparative example, the vertex B of the characteristic line of the first rubber member 6, the vertex C of the characteristic line of the second rubber member 7, and the vertex D of the characteristic line of the present embodiment are respectively The resonance point is shown.

  In the case of the comparative example, in order to obtain a desired vibration isolation effect on the high frequency side of the use frequency band, the elastic modulus is increased, but with this, the resonance point A is located within the range of the use frequency band. Yes. For this reason, in the comparative example, the anti-vibration effect cannot be obtained at the peripheral frequency of the resonance point A.

  On the other hand, the vibration isolator 5 according to the present embodiment is formed by joining the first rubber member 6 and the second rubber member 7 having different elastic moduli.

  As shown in FIG. 4, since the first rubber member 6 is made of a rubber material having a large elastic modulus, the vibration transmissibility change (inclination) with respect to the frequency is large on the higher frequency side than the resonance point B, and the vibration frequency There is a tendency that the vibration transmissibility tends to decrease as the value increases.

  Since the second rubber member 7 is made of a rubber material having a low elastic modulus, the change (inclination) of the vibration transmissibility with respect to the frequency is smaller on the higher frequency side than the resonance point C compared to the first rubber member 6, and vibration is caused. Even if the frequency becomes higher, the vibration transmissibility tends not to decrease. On the other hand, the resonance point C of the second rubber member 7 is lower than the resonance point B of the first rubber member 6.

  As a result, the resonance point D of the vibration isolator 5 according to the present embodiment is lower than the resonance point A of the comparative example and deviates to a lower frequency side than the use frequency band. In addition, in the present embodiment, the vibration transmissibility is reduced over the entire use frequency band as compared with the comparative example. Thus, with the vibration isolator 5 according to the present embodiment, a stable vibration isolating effect can be obtained when the compressor (first member 1) is operated.

  Further, the joint portion between the first rubber member 6 and the second rubber member 7 is an unevenness in which the lower surface 6D and the convex portion 6E of the first rubber member 6 are fitted with the upper surface 7D and the concave portion 7E of the second rubber member 7. It is a fitting part 8. Thereby, the 1st rubber member 6 and the 2nd rubber member 7 have composition which has a normal line direction of a central axis (axis of bolt 9A), and a contact surface of two directions of a central axis direction. Accordingly, the first rubber member 6 and the second rubber member 7 as shown in FIG. 3 are considered to be connected in series in both the normal direction (horizontal direction) of the central axis and the direction of the central axis (vertical direction). be able to. For this reason, a high vibration isolation effect can be obtained not only in the vertical direction but also in the horizontal direction.

  Thus, according to the first embodiment, by fitting the first rubber member 6 and the second rubber member 7 having different elastic constants, it is possible to lower the resonance point and to vibrate on the high frequency side. A high vibration insulation effect can be obtained by reducing the transmissibility.

  Further, the vibration isolator 5 is configured such that the joint portion between the first rubber member 6 and the second rubber member 7 is uneven, so that the first rubber member 6 and the second rubber member 7 are in the vertical direction. They are in contact with each other in both the horizontal direction. Accordingly, the anti-vibration device 5 is provided with the same anti-vibration insulation between the first member 1 and the second member 3 not only in the vertical direction (axial direction) but also in the horizontal direction (normal direction of the axis). An effect can be obtained.

  Furthermore, since the vibration isolator 5 has a simple structure in which rubber materials having different characteristics are joined in series and has a small number of parts, the cost can be reduced and the assembly is easy. It can also be easily installed in a narrow space between the vehicle body and the compressor.

  Next, FIGS. 5 to 7 show a second embodiment of the present invention. A feature of the present embodiment is that a circular tube is provided between the first rubber member and the second rubber member. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is omitted.

  The vibration isolator 11 according to the second embodiment includes a first rubber member 6, a second rubber member 7, a support member 9, and a circular tube 12 described later.

  The circular tube 12 provided between the first rubber member 6 and the second rubber member 7 is formed in a dish shape by projecting the center of a disk-shaped thin plate made of, for example, a metal material downward. The outer diameter dimension is formed in the same manner as the outer diameter dimension of the first rubber member 6 and the second rubber member 7. Specifically, as shown in FIG. 5, the circular tube 12 includes an annular flat plate portion 12A and a protruding portion 12B protruding downward from the flat plate portion 12A.

  The upper surface 12A1 of the flat plate portion 12A is in contact with the lower surface 6D of the first rubber member 6, and the inner surface 12B1 of the protruding portion 12B is in contact with the convex portion 6E of the first rubber member 6. On the other hand, the lower surface 12A2 of the flat plate portion 12A is in contact with the upper surface 7D of the second rubber member 7, and the outer surface 12B2 of the protruding portion 12B is in contact with the concave portion 7E of the second rubber member 7. In addition, a through hole 12C is formed coaxially with the through hole 6F of the first rubber member 6 and the through hole 7F of the second rubber member 7 at the center of the protruding portion 12B.

  Here, in the first embodiment described above, the vibration isolator 5 is configured to directly bond or weld the first rubber member 6 and the second rubber member 7. However, generally, adhesion and welding of rubbers are difficult. Therefore, in the present embodiment, the first circular tube 12 made of a metal material is easily fitted between the first rubber member 6 and the second rubber member 7, that is, by the concave-convex fitting portion 8. Adhesion between the rubber member 6 and the circular pipe 12 and adhesion between the second rubber member 7 and the circular pipe 12 can be performed. That is, the circular pipe 12 constitutes a joining member for joining the first rubber member 6 and the second rubber member 7. Thereby, the vibration isolator 11 has a configuration in which the first rubber member 6 and the second rubber member 7 are integrated via the circular pipe 12.

  As described above, in the vibration isolator 11, the first rubber member 6 and the second rubber member 7 having different elastic constants are connected in series via the circular pipe 12 below the first member 1 that is the object of vibration isolation. It is configured (see FIG. 5).

  Then, the bolt 9A is inserted through the through hole 7F of the second rubber member 7, the through hole 12C of the circular tube 12, and the through hole 6F of the first rubber member 6, and fixed with the nut 9B together with the washers 9C and 9D.

  In this state, the vibration isolator 11 is installed between the first member 1 and the second member 3. At this time, the bolt 9 </ b> A of the support member 9 is inserted between the mounting bracket 2 attached to the first rubber member 6 which is a vibration transmission path and the mounting bracket 4 attached to the second rubber member 7. Therefore, the elongation of the first rubber member 6 and the second rubber member 7 can be restrained.

  Thus, also in the second embodiment configured in this way, the same operational effects as those of the first embodiment described above can be obtained.

  In particular, in the case of the present embodiment, since the fitting function of the rubber material can be enhanced by the circular pipe 12 made of a metal material, the first rubber member 6 and the second rubber member 7 are simply integrated. be able to.

  FIG. 7 shows the analysis results of vibration transmissibility with respect to the vibration frequency for the vibration isolator according to the comparative example, the vibration isolator 5 according to the first embodiment, and the vibration isolator 11 according to the second embodiment. Show. In FIG. 7, the horizontal axis indicates the frequency associated with the vibration when the compressor (first member 1) is operated, and the vertical axis indicates the vibration transmission rate indicating the rate at which the vibration is transmitted to the mounting member (second member 3). Shows the rate. The anti-vibration device according to the comparative example is formed by integrating the first rubber member 6 and the second rubber member 7 using the same rubber material. Further, the vertex A of the characteristic line of the vibration isolator according to the comparative example, the vertex D of the characteristic line of the vibration isolator 5 and the vertex E of the characteristic line of the vibration isolator 11 indicate the resonance points of the respective members.

  The vibration isolator 11 in which the first rubber member 6 and the second rubber member 7 having different elastic moduli are fitted (joined) via the metal circular pipe 12 is a resonance point A of the vibration isolator according to the comparative example. It can be seen that the resonance frequency is lower than the use frequency band and is lower, and the vibration transmissibility on the high frequency side is lower. Thereby, the vibration isolator 11 can obtain a stable vibration isolating effect when the compressor (first member 1) is operated.

  Further, the circular tube 12 can also act as a mass damper. For this reason, in the vibration isolator 11 according to the second embodiment, the vibration transmissibility on the high frequency side can be further reduced as compared with the vibration isolator 5 according to the first embodiment.

  In the present embodiment, the configuration in which the circular tube 12 made of a metal material is fitted between the concave and convex fitting portions 8 of the first rubber member 6 and the second rubber member 7 has been described as an example. However, the present invention is not limited to this, and the circular tube 21 may be configured as a member made of a resin material such as plastic as in the modification shown in FIG.

  In the first embodiment described above, in order to prevent contact between the through hole 6F of the first rubber member 6 and the through hole 7F of the second rubber member 7 and the shaft portion of the bolt 9A, A cylindrical collar (not shown) may be provided between the through hole 6F and the through hole 7F. The length of the collar may be shortened so that the first rubber member 6 and the second rubber member 7 do not come into contact with the shaft portion of the bolt 9A. Two rubber members 7 may be provided separately on the through hole 7F side. The same applies to the second embodiment and the modification.

  In the first embodiment described above, a configuration in which the bolt 9A is inserted from the through hole 7F side of the second rubber member 7 and is fixed by the nut 9B on the upper surface 6A of the first rubber member 6 is taken as an example. explained. However, the configuration is not limited thereto, and the bolt 9A may be inserted from the through-hole 6F side of the first rubber member 6 and fixed by the nut 9B on the lower surface 7A of the second rubber member 7. The same applies to the second embodiment and the modification.

  Further, in the first embodiment described above, the case where the first rubber member 6 is a harder rubber material than the second rubber member 7 has been described as an example. However, the present invention is not limited to this, and the first rubber member 6 may be a softer rubber material than the second rubber member 7. The same applies to the second embodiment and the modification.

  Moreover, in 1st Embodiment mentioned above, the uneven | corrugated fitting part 8 which is a junction part of the 1st rubber member 6 and the 2nd rubber member 7 is used for the convex part 6E of the 1st rubber member 6, and the 2nd rubber member. The case where it is constituted by the seven concave portions 7E has been described as an example. However, the present invention is not limited thereto, and the concave / convex fitting portion may be configured by forming a concave portion in the first rubber member and forming a convex portion in the second rubber member. The same applies to the second embodiment and the modification.

  Furthermore, the concave / convex fitting portion 8 is constituted by a convex portion 6E formed at the center portion of the lower surface 6D of the first rubber member 6 and a concave portion 7E formed at the central portion of the upper surface 7D of the second rubber member 7. The case has been described as an example. However, the present invention is not limited to this. For example, a plurality of convex portions may be formed on the lower surface of the first rubber member, and a plurality of concave portions may be formed on the upper surface of the second rubber member at positions corresponding to the convex portions. That is, the first rubber member and the second rubber member need only be in contact with each other in both the upper and lower directions and the horizontal direction. The same applies to the second embodiment and the modification.

  In the first embodiment described above, the case where the mounting bracket 2 is joined by the groove 6C of the first rubber member 6 and the mounting bracket 4 is joined by the groove 7C of the second rubber member 7 will be described as an example. did. However, the present invention is not limited to this, and any joining means can be employed without being limited to such joining means as long as vibrations in the two directions of the upper, lower, and horizontal directions can be transmitted.

  Moreover, the frequency characteristics of the vibration transmissibility of the first rubber member 6 and the second rubber member 7 in FIG. 4 show an example, and the present invention is not limited to this. That is, if the first rubber member and the second rubber member are used and the resonance frequency is lower than the use frequency band and the vibration transmissibility on the higher frequency side than the resonance frequency is reduced, the first rubber member is used. As the second rubber member, rubber materials having various elastic moduli different from each other can be used.

  In the first embodiment described above, the case where the vibration isolator 5 is attached to the compressor (first member 1) for the air suspension device of the vehicle has been described as an example. However, the present invention is not limited to this. For example, the vibration isolator 5 can be widely applied to a case where vibration generated by the operation of the machine is suppressed from being transmitted to the foundation or the like, such as a vibration isolating measure at the time of the dehydrating operation of the washing machine. . The same applies to the second embodiment and the modification.

DESCRIPTION OF SYMBOLS 1 1st member 3 2nd member 5,11 Anti-vibration device 6 1st rubber member 7 2nd rubber member 8 Concave-concave fitting part 9 Support member 12,21 Circular pipe

Claims (2)

A vibration isolator disposed between the first member and the second member to be damped,
A cylindrical first rubber member having one side attached to the first member;
One side is attached to the second member, and includes a cylindrical second rubber member having a characteristic that the elastic constant is different from that of the first rubber member,
The other side of each of the first rubber member and the second rubber member has an uneven fitting portion,
A vibration isolator, wherein a support member is inserted through an axial center side of the first rubber member and the second rubber member.   The vibration isolator according to claim 1, wherein a member made of a metal material or a resin material is fitted between the concave and convex fitting portions of the first rubber member and the second rubber member.

Images