JP2005337497A - Active damper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an active damper capable of developing an effective active damping effect on the vibration of a plurality of or wide frequency ranges by a small supply energy. <P>SOLUTION: This damper forms a vibration system with at least two degrees of freedom by elastically connecting a first block member 14 to a mounting member 12 fitted to an object 10 to be damped and elastically supporting an additional block member 16 on the first block member 14. On the other hand, an excitation means 22 imparting an excitation force between the mounting member 12 and the first block member 14 is installed to directly impart the excitation force to the first block member 14 and indirectly impart the excitation force to the added block member 16 through the first block member 14. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vibration damper that is mounted on a vibration suppression object and reduces vibrations in the vibration suppression object, and more particularly, an active type vibration suppression device that includes an oscillating means and can reduce vibrations in a positive or destructive manner. It is related to a vibrator.

  2. Description of the Related Art Conventionally, a dynamic vibration absorber (dynamic damper) is known as one of means for reducing vibration in a member where vibration is a problem, such as an exhaust pipe or a body of an automobile. In recent years, in order to obtain a higher level of damping effect, as described in JP-A-61-220925, JP-A-3-292219, etc., the excitation force by the excitation means is used. By doing so, there has been proposed an active vibration damper that can reduce vibrations in a vibration-damping object positively or offsetly. However, in order to obtain an effective damping effect with an active vibration damper, it is necessary to apply an excitation force that is commensurate with the vibration to be damped to the object to be damped. If the vibration energy is large, it is inevitable that the vibration means will be enlarged or the energy consumption for vibration will be large, and it will be difficult to obtain sufficient vibration force. In some cases, the effect could not be obtained.

  In order to deal with such a problem, Japanese Patent Laid-Open Nos. 6-235438 and 7-190139 disclose a mass member that is elastically supported by a mounting member that is attached to a vibration suppression target. By constructing two vibration systems and applying an excitation force to this mass member, the resonance action in the vibration system is used to reduce the energy consumption and to exert a large excitation force on the object to be controlled. Has been proposed.

  However, in the conventional active vibration control device using such a resonance action, an effective excitation force can be exerted on the object to be controlled only in the natural frequency range of a single vibration system. In other frequency ranges, there was a problem that it was not always possible to exert an effective excitation force. In particular, a vibration isolation effect was required for vibrations in a plurality of frequency bands or a wide frequency range. However, it is still difficult to satisfy the required anti-vibration performance in automobile bodies and the like.

Here, the present invention has been made in the background as described above, and the problem to be solved is an effective active damping effect that generates a large excitation force while suppressing energy consumption. It is another object of the present invention to provide an active vibration damper having a novel structure that can exhibit an effective vibration damping effect against a plurality of vibrations in a wide frequency range.

  Hereinafter, the aspect of this invention made | formed in order to solve such a subject is described. In addition, each aspect described below can be employed in any combination as much as possible. In addition, aspects or technical features of the present invention are not limited to those described below, but are described in the entire specification and drawings, or invented by those skilled in the art from those descriptions. It should be understood that it is recognized on the basis of.

  That is, according to the present invention, the first mass member is disposed so as to be relatively displaceable in the vibration input direction with respect to the attachment member attached to the vibration suppression target, and the attachment member and the first mass member are elastically arranged. And at least one additional mass member is disposed relative to the first mass member so as to be relatively displaceable in the vibration input direction, so that the additional mass member is elastic with respect to the first mass member. The vibration means having a plurality of natural frequencies is configured by supporting the vibration member, and vibration means for exerting a relative vibration force in the vibration input direction between the mounting member and the first mass member is provided. An active vibration damper is provided.

  In such an active vibration damper having a structure according to the present invention, the first mass member and the additional mass member are coupled and elastically coupled to and supported by the object to be damped. A multi-degree-of-freedom vibration system with a degree of freedom is configured. Then, the excitation force exerted on the first mass member by the vibration means is transmitted to the multi-degree-of-freedom vibration system and vibrated, so that the mounting member and the control member are controlled via the multi-degree-of-freedom vibration system. It will be affected by the shake target.

  Therefore, by appropriately tuning multiple natural frequencies in a multi-degree-of-freedom vibration system, the excitation force by the excitation means is amplified in the frequency range of each natural frequency based on the resonance action of the vibration system. Will be exerted on the mounting member. Therefore, by appropriately tuning each natural frequency according to the vibration to be damped, a large oscillating force can be exerted on the object to be damped with respect to the energy supplied to the oscillating means. An effective vibration damping effect can be obtained by a small-sized vibration means with low energy consumption. In the present invention, preferably, the additional mass member is elastically connected to the mounting member via the first mass member, whereby a vibration system having a plurality of natural frequencies as a whole is configured. In this case, an excitation force is directly applied to the first mass member by the excitation means, and an excitation force is indirectly applied to the additional mass member via the first mass member. Will be affected.

  In the present invention, when tuning a plurality of natural frequencies, for example, it is effective to tune each natural frequency to each frequency of a different vibration to be vibration-proofed. When the frequency of each vibration to be performed is substantially constant and relatively narrow, an efficient vibration damping effect can be realized. In addition, for example, it is possible to tune two of the natural frequencies in such a plurality of vibration systems by shifting them to the low frequency side and the high frequency side with respect to one vibration to be damped. When the frequency range of one vibration to be damped is wide or the frequency of the vibration to be damped fluctuates, it is possible to stably obtain an effective vibration damping effect. The range of the natural frequency to be shifted to the low frequency side and the high frequency side with respect to the vibration to be damped is appropriately set according to the vibration characteristics to be damped and is particularly limited. However, in order to obtain a particularly effective damping effect over a wide range, the two natural frequencies should be set to both sides within ± 20% of the vibration frequency median for the purpose of reduction. desirable.

  Further, as the vibration means in the present invention, various known ones that can adjust the frequency of the vibration force exerted on the first mass member can be adopted. As such vibration means, between the opposing surfaces of the mounting member and the first mass member, a working air chamber in which a part of the wall portion is configured by an elastic member that elastically connects the mounting member and the first mass member; Pneumatic excitation means configured to include pressure control means for exerting a pressure change on the working air chamber is employed. In such a pneumatic vibration means, the frequency of the generated vibration force can be adjusted by adjusting the frequency of the change in air pressure exerted on the working air chamber. There is an advantage that it is not necessary to incorporate a device. Note that the transmission of the air pressure fluctuation to the working air chamber can be advantageously realized, for example, by alternately switching the working air chamber between the negative pressure source and the atmosphere using an electromagnetic switching valve or the like. Here, the pressure change by the pressure control means is preferably exerted on the working air chamber through a passage provided in the mounting member. Thereby, it is possible to avoid deformation or displacement of a pipe line or the like that causes air pressure fluctuation when the first mass member or the additional mass member is displaced by vibration.

  Alternatively, as the vibration means in the present invention, for example, one constituted by an electromagnetic driving means including a coil member fixed on the mounting member side and a magnet member fixed on the first mass member side is also available. Can be advantageously employed. Such an electromagnetic excitation means has an advantage that the generated excitation force can be controlled with high accuracy by controlling the energization of the coil member with an electric circuit. In particular, by fixing the coil member to the mounting member side, the lead wire for power feeding and the like is not bent even when the mass member is displaced, and excellent durability can be ensured.

  In the present invention, the relative arrangement structure of the first mass member and the additional mass member is appropriately designed according to the installation space of the vibration damper, the required vibration damping characteristics, and the like. For example, the mounting member and the first mass member are spaced apart from each other in the vibration input direction, and one of the additional mass members is annular, and the annular additional mass member is disposed with respect to the first mass member. Thus, a structure that is arranged on the outer peripheral side in a direction orthogonal to the vibration input direction is advantageously employed. In such a mass member arrangement structure, the first mass member and the annular additional mass member can be arranged with excellent space efficiency while advantageously securing the mass. Further, if such an annular additional mass member is employed, for example, a rubber elastic body is interposed between the first mass member and the radially opposing surface of the additional mass member, whereby the first mass member and the additional mass member are added. It is also possible to configure the elastic member that connects the mass members with a rubber elastic body in which the main deformation at the time of vibration input is generated by shearing, and thereby the degree of freedom of tuning the natural frequency to the low frequency side Is also advantageously secured.

  In the present invention, it is sufficient that there is at least one additional mass member. For example, when there are a plurality of mass members, each mass member is independently elastically supported by the main mass member with respect to the main mass. It is also possible to elastically support these mass members in parallel to the main body mass member, or to connect the other mass members to the mass member elastically supported to the main body mass member. By doing so, it is also possible to elastically support a plurality of mass members in series with the main mass member.

  Further, in the present invention, a plurality of natural frequencies can be obtained by solving a motion equation in a known two-degree-of-freedom or multi-degree-of-freedom vibration system. Is possible.

  In the active vibration damper having the structure according to the present invention, a vibration system having at least two degrees of freedom is configured. Therefore, based on the resonance action of the vibration system, a plurality of vibrations in a wide frequency range can be detected. However, the active vibration damping effect can be obtained effectively and efficiently.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

  First, FIG. 1 shows an overall schematic configuration of an active vibration damper 8 as a first embodiment of the present invention. The vibration damper 8 includes a first mass member 14 as a first mass member and an additional mass member as an attachment member 12 as an attachment member attached to a vibration suppression target 10 such as an automobile body. The second mass metal fitting 16 is elastically connected by the first rubber member 18 and the second rubber member 20, and a vibration system having two degrees of freedom is configured as a whole. The mounting bracket 12 and the first mass bracket 14 are relatively displaced in the approaching / separating direction from each other by the electromagnetic actuator 22 as a vibration means incorporated between the mounting bracket 12 and the first mass bracket 14. Thus, by transmitting the excitation force to the vibration suppression target 10, vibrations in the vibration suppression target 10 are counterbalanced or interfered. In the following explanation, the vertical direction means the vertical direction in FIG. 1 in principle.

  More specifically, the mounting bracket 12 is formed by superimposing a first plate fitting 24 and a second plate fitting 26 each having a disk shape and fixing them together with fixing bolts 27. In addition, an accommodation recess 30 is formed in the central portion of the second metal plate 26 so as to open to a surface overlapped with the first metal plate 24, and the head is accommodated in the accommodation recess 30. A guide rod 34 is fixed by a support bolt 32 having a leg protruding downward in the axial direction. The guide rod 34 is formed of a hard material such as a metal and extends linearly with a substantially constant cross-sectional shape. The guide rod 34 protrudes downward in the axial direction on the central axis of the mounting bracket 12. A stopper 36 that extends in the direction perpendicular to the axis is formed integrally with the protruding tip.

  In addition, a bobbin 38 spreading in a skirt shape in the axially outward direction is overlapped at the center of the lower surface of the second metal plate 26, and the second metal plate is fixed by a guide rod 34 fixed by a support bolt 32. 26 is fixed. The bobbin 38 is made of an electrically insulating material such as a synthetic resin, and a coil 40 is wound around and fixed to a cylindrical portion provided at a protruding tip portion in the axial direction.

  Furthermore, a bolt hole 42 that extends in the axial direction is formed in the first plate member 24 that constitutes the attachment member 12, and the attachment member 12 is attached by the attachment bolt 28 that is screwed into the bolt hole 42. Is fixedly attached to the object 10 to be controlled.

  On the other hand, the first mass bracket 14 includes a coupling bracket 44, a mass block 46, and a permanent magnet 48. The connecting metal fitting 44 has an annular block shape, and is arranged with a predetermined amount biased coaxially and axially downwardly away from the attachment metal fitting 12 in the radial direction. Then, the second plate metal member 26 and the connecting metal member 44 constituting the attachment metal member 12 are connected to each other by the first rubber member 18. The first rubber member 18 as a whole has a substantially annular plate shape or a tapered cylindrical shape, and is attached to the inner peripheral surface of the end portion on the small diameter side (second plate member 26). ) Is vulcanized and bonded, and the inner peripheral surface of the connecting fitting 44 is vulcanized and bonded to the outer peripheral surface of the end portion on the large diameter side. The opposing surfaces of the second metal plate 26 and the connecting metal member 44 connected by the first rubber member 18 are inclined surfaces that face each other in the oblique axis direction (the connecting direction by the first rubber member 18). Yes.

  The mass block 46 is formed of a ferromagnetic material such as iron and made of a material having a high specific gravity and has a large-diameter circular block shape. A guide hole 50 penetrating in the axial direction is formed on the central axis. A sliding bush 52 is incorporated in the guide hole 50. Further, the mass block 46 is formed with an annular concave groove 54 that continuously extends in the circumferential direction in the radial direction and opens on one axial side (the upper side in FIG. 1). A permanent magnet 48 is inserted into the groove 54 and fixed to the inner surface of the outer peripheral side wall of the annular groove 54. The permanent magnet 48 may be continuous over the entire circumference in the circumferential direction or may be discontinuous. In the permanent magnet 48, both magnetic poles are set on the inner peripheral surface side and the outer peripheral surface side, whereby a donut-shaped magnetic path is formed as a whole in the mass block 46. An annular groove 54 is positioned on the magnetic path to form a cylindrical magnetic gap as a whole.

  The mass block 46 is opposed to the mounting bracket 12 so as to be spaced downward in the axial direction on the same central axis, and the facing surface of the mass block 46 is overlapped with the coupling bracket 44 to connect the coupling bolt. By being fixed at 58, the mass block 46 is elastically connected to the mounting bracket 12 via the first rubber member 18.

  The mass block 46 is fixedly provided with an annular buffer rubber 60 protruding toward the mounting bracket 12 around the upper end opening of the guide hole 50, and the mass block is interposed via the buffer rubber 60. 46 abuts on the mounting bracket 12 side (the bottom wall portion of the bobbin 38), so that the relative displacement amount in the axial direction of the mounting bracket 12 and the first mass bracket 14 is limited in a buffering manner. It has become. A large-diameter recess 62 is formed at the lower end opening end of the guide hole 50 in the mass block 46, and the stopper portion 36 of the guide rod 34 is accommodated in the large-diameter recess 62. . When the first mass fitting 14 is greatly displaced in the separation direction with respect to the mounting fitting 12, the stopper portion 36 of the guide rod 34 comes into contact with the bottom surface of the large-diameter recess 62 of the mass block 46. The relative displacement amount of both the metal parts 12 and 14 is limited. A buffer rubber 64 is disposed on the bottom surface of the large-diameter recess 62 so that the stopper portion 36 of the guide rod 34 abuts on the buffer.

  Further, the second mass metal fitting 16 is disposed on the outer peripheral side of the mass block 46. The second mass metal fitting 16 has a substantially thick cylindrical shape as a whole, and is disposed on the same central axis as the mass block 46 so as to be spaced radially outward of the mass block 46. . In particular, in the present embodiment, the masses of the first mass bracket 14 and the second mass bracket 16 are set to be substantially the same. A second rubber member 20 is interposed between the radially opposing surfaces of the outer peripheral surface of the mass block 46 and the inner peripheral surface of the second mass metal fitting 16. The second rubber member 20 has a thick cylindrical shape, and the outer peripheral surface of the mass block 46 is vulcanized and bonded to the inner peripheral surface thereof, and the second mass fitting 16 is attached to the outer peripheral surface thereof. The inner peripheral surface is vulcanized and bonded. As a result, the second mass bracket 16 is elastically connected and supported to the mass block 46 via the second rubber member 20. In the present embodiment, the second rubber member 20 is formed as an integrally vulcanized molded product including the mass block 46 and the second mass metal fitting 16.

  In short, in the present embodiment, the first mass bracket 14 and the second mass bracket 16 are sequentially arranged in series with respect to the mounting bracket 12 via the first rubber member 18 and the second rubber member 20. Accordingly, a vibration system having two degrees of freedom is configured.

  On the other hand, the coil 40 supported by the mounting bracket 12 is inserted and disposed in the annular groove 54 of the mass block 46, and the annular groove formed by the inner peripheral side wall surface of the annular groove 54 and the permanent magnet 48. Between the outer peripheral side wall surface of the groove | channel 54 and the radial direction opposing surface, it arrange | positions so that a displacement in an axial direction is possible. The coil 40 is supplied with a drive current from an external control device through a power supply lead wire (not shown). When the drive current is supplied to the coil 40, the coil 40 and the mass block are supplied. 46, an electromagnetic force is generated, so that a relative displacement force in the approach / separation direction on the central axis is exerted between the mounting bracket 12 and the first mass bracket 14. Yes. In particular, by making the direction of the current flowing through the coil 40 reverse, the relative displacement force exerted between the mounting bracket 12 and the first mass bracket 14 can be reversed, By applying an alternating current, an axial relative excitation force is exerted on the mounting bracket 12 and the first mass bracket 14. In short, in this embodiment, the electromagnetic actuator 22 that includes the coil 40 wound around the bobbin 38 and the permanent magnet that forms a magnetic path in the mass block 46 and exerts an excitation force on the first mass fitting 14 is provided. It is composed.

  In the active vibration damper 8 having such a structure, the first and second mass brackets 14 are fixed by fixing the mounting bracket 12 to the damping object 10 with the fixing bolt 28 as described above. , 16 are mounted in a state where the elastic displacement direction (the direction of the central axis) substantially coincides with the vibration direction (vertical direction in FIG. 1) of the object to be damped.

  In the vibration damper 10 having the above-described structure, when the coil 40 is energized, the axial excitation force based on the electromagnetic force generated between the coil 40 and the magnetic field of the permanent magnet 48 is the first. It is applied directly to the one mass bracket 14 and indirectly to the second mass bracket 16 via the second rubber member 20, so that the first and second A two-degree-of-freedom vibration system composed of the mass fittings 14 and 16 and the first and second rubber members 18 and 20 is forcibly excited. Here, the vibration system has two inherent characteristics obtained from the respective masses of the first and second mass fittings 14 and 16 and the respective spring constants of the first and second rubber members 18 and 20 by a frequency equation. Since the vibration system has a vibration frequency, when the vibration system is vibrated in the frequency range corresponding to each natural frequency, the mass brackets 14 and 16 are largely displaced by the resonance action of the vibration system, and a large vibration force is generated. Therefore, by tuning the natural frequency of such a vibration system to the frequency range to be controlled in the vibration control target 10, small power consumption is achieved in those natural frequency ranges. Thus, an effective active vibration suppression effect can be obtained for the vibration suppression target 10.

  In particular, since the vibration damper 8 has a vibration system with two degrees of freedom, a large degree of freedom in tuning with respect to vibration to be damped is ensured, and an effective vibration damping effect is easily achieved. The Rukoto. Specifically, for example, if the two natural frequencies are set relatively close to each other, the active vibration suppression effect based on the resonance action can be improved in a wide frequency range including the two natural frequencies. In addition, when the two natural frequencies are set relatively far apart, it is possible to improve the active vibration suppression effect based on the resonance action in two separate frequency ranges. Therefore, in the former case, in order to obtain an effective damping effect in as wide a frequency range as possible while avoiding a drop in the active damping effect between the two natural frequencies, the two natural frequencies are used. It is desirable to set a gap between the two sides within ± 20% of the median vibration frequency for reduction.

  In addition, as a control device that controls the excitation of the electromagnetic actuator 22 by controlling the energization of the coil 40, the vibration is based on the detection signal of a vibration sensor such as an acceleration sensor that detects the vibration state of the vibration suppression target 10. In order to exhibit an effective vibration damping effect, a device that outputs a drive current corresponding to the detection signal to the coil 40 is employed. For example, on the basis of preset data, a drive current having a magnitude corresponding to the magnitude of the detection signal is controlled in a feed-forward manner by feeding the detection signal with a predetermined phase difference, or A device that feedback-controls the magnitude of the drive current or the like so as to make the vibration value of the vibration suppression target 10 included in the detection signal as zero as possible can be suitably employed.

  Incidentally, FIG. 2 shows the result of measuring the frequency characteristics of the acceleration response (displacement response or synonymous with resonance magnification) of the forced vibration caused by the sinusoidal external force for the active vibration damper 8 having the structure according to the present embodiment. . In the figure, Example 1 is a case where two natural frequencies are tuned to about 35 Hz and about 105 Hz, and Example 2 is tuned to about 30 Hz and about 40 Hz by bringing the two natural frequencies close to each other. This is the case. In addition, as a comparative example, the results of a similar test performed on a damper having a single mass structure in which the first mass metal fitting 14 and the second mass metal fitting 16 are rigidly connected to each other and cannot be displaced relative to each other are also shown. .

  As is clear from the results shown in FIG. 2, in the active vibration damper 8 having the structure according to the present embodiment, the resonance action by the vibration system with two degrees of freedom is remarkably expressed. Therefore, it is easy to understand that by using the resonance action in each natural frequency range, an active damping effect can be effectively obtained even for vibrations in a wide frequency range or different frequency ranges. It is where it is done.

  Further, in the vibration damper 8 of the present embodiment, the coil 40 constituting the electromagnetic actuator 22 is fixed to the mounting attachment 12 and is attached to the vibration suppression target 10 so as not to be relatively displaceable. Therefore, deformation of the power supply lead wire to the coil 40 during vibration system vibration is avoided, disconnection trouble due to repeated deformation of the power supply lead wire is prevented, and durability is improved. Can be illustrated.

  Next, FIG. 3 shows an overall schematic configuration of an active vibration damper 70 as a second embodiment of the present invention.

  As in the first embodiment, the vibration damper 70 of the present embodiment is provided with a first mass member 74 as a first mass member and an additional mass member with respect to the mounting member 72 attached to the vibration suppression target 10. The second mass metal fitting 76 is elastically connected by the first rubber member 78 and the second rubber member 80, and a two-degree-of-freedom vibration system is formed as a whole. A relative displacement force (excitation force) is applied between the mounting bracket 72 and the first mass bracket 74 by the pneumatic actuator 68 serving as the excitation means in a direction in which they are approached / separated from each other. The vibration in the vibration control target 10 is suppressed or canceled in an interference manner. In the following description, the vertical direction means the vertical direction in FIG. 3 in principle.

  More specifically, the mounting bracket 72 has a thin flat plate shape, and a plurality of mounting holes 82 are formed in the outer peripheral edge portion so as to be spaced apart from each other in the circumferential direction. The mounting bracket 72 is fixedly attached to the damping target 10 by a fixing bolt 84 that is superimposed on the damping target 10 and inserted through the mounting hole 82. A through hole 86 is formed at the center of the mounting bracket 72, and a cylindrical supply / discharge port 88 is welded and fixed to the through hole 86 in a fluid-tight manner.

  Further, the first mass metal fitting 74 is formed with a solid block shape by a high specific gravity rigid material such as metal, and in particular, in this embodiment, it is a thick disk-shaped block shape. And this 1st mass metal fitting 74 is spaced apart above the attachment metal fitting 72, and is opposingly arranged.

  Furthermore, a first rubber member 78 is disposed between the opposing surfaces of the mounting bracket 72 and the first mass bracket 74. The first rubber member 78 has an annular shape or a cylindrical shape. The lower end surface in the axial direction is vulcanized and bonded to the mounting bracket 72, and the caulking fixing bracket 90 is attached to the upper end surface in the axial direction. Is vulcanized and bonded. The caulking fixing metal fitting 90 has an annular plate-shaped adhesive portion 92 vulcanized and bonded to the upper end surface of the first rubber member 78, and the outer peripheral edge portion of the adhesive portion 92 has an axial direction. A cylindrical portion 94 extending upward is integrally formed. The cylindrical portion 94 is extrapolated to the first mass fitting 74 and the upper end in the axial direction is caulked inward in the radial direction, whereby the caulking fixing fitting 90 is the outer peripheral edge portion of the first mass fitting 74. Thus, the outer peripheral edge portion of the first mass fitting 74 and the opposing surface of the attachment fitting 72 are connected by the first rubber member 78 so that the first mass fitting 74 is attached. The metal member 72 is elastically supported.

  Further, the caulking fixing metal fitting 90 is assembled fluid-tightly with respect to the first mass metal fitting 74, so that the outer peripheral wall portion is between the opposing surfaces of the attachment metal fitting 72 and the first mass metal fitting 74. A working air chamber 96 which is composed of one rubber member 78 and is sealed with respect to the external space is defined. An external air line 98 is connected to the working air chamber 96 through a supply / exhaust port 88, and the switching operation of an electromagnetic switching valve 100 disposed on the external air line 98 is performed. Based on the above, the working air chamber 96 is alternately switched between the negative pressure source and the atmosphere. Thus, negative pressure and atmospheric pressure are alternately exerted on the working air chamber 96 by the switching operation of the switching valve 100 to generate air pressure fluctuations, thereby forming a part of the wall portion of the working air chamber 96. An excitation force in the approach / separation direction to the mounting bracket 72 is exerted on one mass bracket 74, and the first mass bracket 74 is axially moved based on the elastic deformation of the first rubber member 78. It is designed to be displaced by excitation (vertical direction in FIG. 3). As is clear from this, in the present embodiment, the pneumatic actuator 68 is configured to include the working air chamber 96 and the switching valve 100 for exerting a change in air pressure on the working air chamber 96. .

  Further, a second mass fitting 76 is disposed above the first mass fitting 74 at a predetermined distance. Like the first mass fitting 74, the second mass fitting 76 is formed in a solid block shape from a high specific gravity rigid material such as metal. In particular, in the present embodiment, the first mass fitting 76 is formed. It is a thick disk-shaped block shape that is slightly smaller than the metal fitting 74. The second mass bracket 76 is disposed opposite to the upper side of the first mass bracket 74 so as to be spaced apart upward.

  A second rubber member 80 is disposed between the opposing surfaces of the first mass fitting 74 and the second mass fitting 76. The second rubber member 80 has a block shape, the lower end surface in the axial direction is vulcanized and bonded to the center of the upper surface of the first mass fitting 74, and the upper end surface in the axial direction is the second mass. Vulcanized and bonded to the center of the lower surface of the metal fitting 76. As a result, the opposing surfaces of the upper end surface of the first mass fitting 74 and the lower end surface of the second mass fitting 76 are connected by the second rubber member 80, and the first mass fitting 74 and the second mass fitting 74 are connected to each other. Mass fittings 76 are elastically connected.

  In short, in the active vibration damper 70 having the above-described structure, the first mass metal fitting 74 and the second mass metal fitting 76 with respect to the attachment metal fitting 72 are replaced with the first rubber member 78 and the second rubber fitting 78. The rubber members 80 are sequentially elastically connected in series via the rubber member 80, thereby forming a vibration system with two degrees of freedom.

  In the active vibration damper 70 having such a structure, the first and second mass brackets 74 are fixed by fixing the mounting bracket 72 to the damping object 10 with the fixing bolt 84 as described above. , 76 are mounted in a state where the elastic displacement direction (the direction of the central axis) substantially coincides with the vibration direction (vertical direction in FIG. 3) to be damped in the object to be damped.

  Therefore, in the active vibration damper 70 having the above-described structure, the electromagnetic switching valve 100 is controlled to be switched at a frequency or phase corresponding to the vibration to be damped in the vibration damped object 10, thereby having two degrees of freedom. Thus, the same vibration effect as that of the first embodiment can be exerted, and an effective active vibration isolation effect can be obtained for the vibration suppression target 10. It can be done.

  In particular, in the active vibration damper 70 of the present embodiment, the first and second mass fittings 74 and 76 can be vibrated by the action of air pressure. There is no need to incorporate it inside, and there is an advantage that simplification of the structure of the active vibration damper 70 and improvement in manufacturability are achieved.

  In the embodiment, when the switching control of the electromagnetic switching valve 100 is performed, as in the first embodiment, a signal having a correlation with the vibration to be controlled in the vibration suppression target 10 or the vibration in the vibration suppression target 10 is obtained. Based on the detection signal, various known feedback and feedforward techniques are used to reduce the vibration of the vibration suppression target 10 as much as possible. The frequency and phase corresponding to the vibration to be damped in the damping object 10 are adjusted so that the magnitude is given as necessary.

  As mentioned above, although embodiment of this invention was explained in full detail, these are illustration to the last, Comprising: This invention is not interpreted limited at all by the specific description in these embodiment.

  For example, in the above-described embodiments, one additional mass member (16, 76) is elastically connected to the first mass member (14, 74). Of course, it is also possible to elastically connect to the first mass member. In addition, when two or more additional mass members are employed, the first mass member is elastically connected to each other via another elastic member, thereby being paralleled by a plurality of additional mass members. It is possible to form a plurality of vibration systems, or to add a plurality of additional mass members by elastically connecting another additional mass member to the additional mass member elastically connected to the first mass member. A plurality of series vibration systems may be formed by mass members.

  In addition, the elastic connection position and the elastic connection structure of the additional mass member with respect to the first mass member are not limited in any way. For example, in the vibration damper 70 shown in the second embodiment, the large-diameter An annular or cylindrical second mass metal fitting is adopted, and the second mass metal fitting is arranged on the outer peripheral side of the first mass metal fitting 74 so as to be extrapolated. It is also possible to elastically connect the second mass fitting and the second mass fitting by a rubber elastic body disposed between the radially opposing surfaces of the two mass fittings.

  Furthermore, it is desirable that each mass of the plurality of mass members is set within a range of 50 to 150% of the average mass of all the mass members. The effect of increasing the vibration force can be obtained more effectively, and a more effective vibration isolation effect can be obtained in each natural frequency range.

  In addition, the present invention is applicable not only to a body vibration damper for automobiles, but also to a vibration damper for various parts of automobiles, or an active vibration damper in various devices other than automobiles. Needless to say.

In addition, although not enumerated one by one, the present invention can be carried out in a mode to which various changes, modifications, improvements, and the like are added based on the knowledge of those skilled in the art. It goes without saying that all are included in the scope of the present invention without departing from the spirit of the present invention.

It is longitudinal cross-sectional explanatory drawing which shows the vibration damper as 1st embodiment of this invention. It is a graph which shows the result of having measured the frequency characteristic of the passive resonance magnification in the vibration damper shown in FIG. It is a longitudinal cross-sectional explanatory drawing which shows the vibration damper as 2nd embodiment of this invention.

Explanation of symbols

8, 70 Damping device 10 Damping object 12, 72 Mounting bracket 14, 74 First mass bracket 16, 76 Second mass bracket 18, 78 First rubber member 20, 80 Second rubber member 22 Electromagnetic Actuator 68 Pneumatic actuator

Claims (8)

  The first mass member is disposed so as to be relatively displaceable in the vibration input direction with respect to the attachment member attached to the vibration suppression target, and the attachment member and the first mass member are elastically connected, and the first mass member By disposing at least one additional mass member relative to one mass member so as to be relatively displaceable in the vibration input direction, and elastically supporting the additional mass member with respect to the first mass member, While constituting a vibration system having a plurality of natural frequencies, a vibration means for applying a relative vibration force in a vibration input direction is provided between the mounting member and the first mass member. Active vibration damper.   An additional mass member is elastically connected to the mounting member via the first mass member to constitute a vibration system having a plurality of natural frequencies as a whole, while the vibration means is used to The excitation force is directly exerted on the mass member, and the excitation force is indirectly exerted on the additional mass member via the first mass member. Active vibration damper.   A working air chamber in which a part of the wall is configured by an elastic member that elastically connects the mounting member and the first mass member between the mounting member and the first mass member between the opposing surfaces of the vibration means. And an active vibration damper according to claim 1, comprising pressure control means for exerting a pressure change on the working air chamber.   4. The active vibration damper according to claim 3, wherein a pressure change by the pressure control means is exerted on the working air chamber through a passage provided in the mounting member.   The said vibration means is comprised by the electromagnetic drive means containing the coil member fixed by the said attachment member side, and the magnet member fixed by the said 1st mass member side. Active vibration damper.   The mounting member and the first mass member are spaced apart from each other in the vibration input direction, and one of the additional mass members is annular, and the annular additional mass member is used as the first mass member. The active vibration damper according to any one of claims 1 to 5, wherein the active vibration damper is disposed apart from the outer peripheral side in a direction orthogonal to the vibration input direction.   The active vibration damper according to any one of claims 1 to 6, wherein two of the plurality of natural frequencies are tuned by shifting them to a low frequency side and a high frequency side with respect to one vibration to be damped.   The active vibration damper according to any one of claims 1 to 6, wherein the plurality of natural frequencies are tuned to respective frequencies of different vibrations to be damped.

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