JP4505750B2 - Vibration control device - Google Patents

Description

  The present invention relates to a vibration damping device that is mounted on a vibration member such as a steering wheel of an automobile to reduce the vibration of the vibration member.

  2. Description of the Related Art Conventionally, various vibration damping devices have been proposed and employed for reducing vibrations in vibration members where vibrations are a problem, such as automobile steering. As one of such vibration damping devices, a dynamic damper is known in which a mass member is elastically supported via a spring member on a vibration member to be damped so as to constitute a secondary vibration system for the vibration member. Yes. In such a dynamic damper, the natural frequency of the sub-vibration system is tuned to a vibration frequency that causes a problem in the vibration member that is the main vibration system, and effective damping against vibrations in the tuning frequency range of the vibration member. The effect will be demonstrated.

  By the way, in the vibration member, there are cases where the vibration suppression effect at a specific frequency alone is insufficient. For example, steering damping in an automobile requires a damping effect in a plurality of or a wide frequency range. However, in the conventional dynamic damper, the vibration damping effect is exhibited at a specific vibration frequency in which the natural frequency of the secondary vibration system is tuned, while the vibration damping effect is effectively obtained in other frequency ranges. It is difficult. Therefore, when vibration in a plurality of or a wide frequency range becomes a problem, it is difficult to cope with the dynamic damper, and there is a possibility that an effective damping effect cannot be obtained.

  In view of this, the present applicant is able to make a relative displacement in a non-adhesive manner with a gap with respect to the rigid housing fixed to the vibration member in Patent Document 1 (International Publication WO00 / 14429) as the previous application. An independent mass member is accommodated in the housing and elastically abutted against the housing at the time of vibration input, thereby canceling out the sliding friction and the energy loss due to the collision at the time of abutment. We proposed a vibration damping device with a novel structure that can achieve a realistic vibration damping effect. The vibration damping device having such a structure can be manufactured with a simple structure, and an effective vibration damping effect can be obtained with respect to vibrations over a wide frequency range.

  However, further research and experiments by the inventor have revealed that there is still room for improvement in the vibration damping device described in Patent Document 1. That is, in the vibration damping device described in Patent Document 1, there is a possibility that the independent mass member does not jump well when a small amplitude vibration is input. In such a case, the contact force of the independent mass member with respect to the housing is effectively obtained. I can't. Therefore, there is a possibility that effective damping performance cannot be exhibited when damping against minute amplitude vibration is also required. Further, in the vibration damping device described in Patent Document 1, the independent mass member and the housing are damped by being struck under substantially a single contact condition (such as a contact force or a contact direction acting by contact). Depending on the required damping performance, it may be difficult to say that the frequency range in which the damping effect is effectively exhibited is sufficiently wide.

International Publication WO00 / 14429

  Here, the present invention has been made in the background as described above, the place to be solved is that it is possible to obtain an effective damping effect in a wider frequency range, An object of the present invention is to provide a vibration damping device having a novel structure capable of exhibiting a vibration damping effect even when a minute vibration is input.

  Hereinafter, the aspect of this invention made | formed in order to solve such a subject is described. In addition, the component employ | adopted in each aspect as described below is employable by arbitrary combinations as much as possible. Further, 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 an invention that can be understood by those skilled in the art from those descriptions. It should be understood that it is recognized based on thought.

That is, according to the present invention, in the damping device, a spring member that forms a recess that opens downward in a rigid housing that is fixedly provided to the vibration member to be damped and covers the opening of the recess. A mass accommodating space is formed, and an independent mass member having a circular cross section is accommodated in the mass accommodating space so as to be independently displaceable without adhesion, while the outer peripheral surface of the independent mass member and the inner space of the housing An intervening rubber layer is deposited and formed at a relative contact portion on at least one of the peripheral surface and at least a part of the side wall surface of the inner peripheral surface of the housing is inclined with respect to the repulsion direction of the spring member And the spring member is formed to include a leaf spring formed of a metal material. The leaf spring is fixed to the housing in a cantilever manner. The free end of the spring Said inclined abutting surface of the mass housing space in the housing is brought located on the side of the side wall which is provided, characterized.

  In the vibration damping device having the structure according to the present invention, for example, due to energy loss caused by motion friction caused by the independent mass member slidingly contacting or rolling with respect to the inclined contact surface via the interposed rubber layer. For the combined action of multiple damping effects such as damping action, damping action by abutment of independent mass member against vibrating member, and damping action by sub-vibration system including spring member Based on this, it is possible to realize effective damping for vibration input in a wide frequency range.

  In addition, by covering the relative abutting portion of at least one of the inner peripheral surface of the recess formed in the housing and the surface of the independent mass member with an intervening rubber layer, it occurs when the independent mass member abuts on the housing. It is possible to reduce the contact sound, and more effectively control the vibration by increasing the frictional resistance between the independent mass member and the housing, and further by the damping action due to the shear deformation of rubber at the time of contact. An effect can be obtained.

  Further, by providing a recess so as to open below the housing, and forming a mass accommodation space by covering the opening of the recess with a spring member, and providing an independent mass member in this mass accommodation space Even when minute vibrations are input in the vertical direction, relative displacement of the independent mass member with respect to the housing (vibrating member) is generated, and the vibration damping effect is effectively exhibited.

  Preferably, the independent mass member has a circular cylindrical section extending in the horizontal direction. According to this, the independent mass member is brought into line contact with the side wall surface of the housing over substantially the entire length in the axial direction. Therefore, a stable contact state between the housing and the independent mass member can be realized by increasing the contact area between the housing and the independent mass member.

  Furthermore, in a stationary state, it is desirable that the bottom wall surface of the mass accommodating space formed by the spring member is inclined downward toward the side wall surface having the inclined contact surface. According to this, the independent mass member is stably brought into contact with the inclined contact surface by the relative displacement of the independent mass member with respect to the housing due to vibration input. Therefore, it is possible to more advantageously obtain a vibration damping effect based on the kinetic friction or the contact action between the independent mass member and the inclined contact surface of the housing.

  Preferably, the inclined contact surface is formed of a curved surface that continuously curves with a common tangent, and the curvature radius of the curved surface is larger than the curvature radius of the surface of the mass member. Has been. According to this, the independent mass member having a circular cross section can be more stably brought into contact with the inclined contact surface, and a vibration damping effect based on friction or the like can be stably obtained.

In addition, the present invention employs a metal leaf spring that is substantially undamped as a spring member, thereby displacing the independent mass member even when a minute amplitude vibration is input, thereby exhibiting an effective damping effect. Is possible. Moreover, by Tei Rukoto spring member (leaf spring) is fixed to the cantilever shape to the housing, the spring member is deformed bending by the weight of the independent mass member, a horizontal direction one-independent mass member by the action of gravity It is biased in the direction (side wall surface side having the inclined contact surface). Therefore, the contact between the independent mass member and the housing (inclined contact surface) can be realized more advantageously, and the damping effect can be effectively exhibited.

  On the other hand, the spring member may include a rubber elastic plate. This also makes it possible to effectively displace the independent mass member, for example, by converting the kinetic energy into heat due to friction between the independent mass member and the housing, or by canceling the independent mass member against the housing and the spring member. Therefore, it is possible to effectively exhibit a vibration damping effect based on a typical contact action.

  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 a vibration damping device 10 as a first embodiment of the present invention. The vibration damping device 10 is fixedly attached to a vibration member (not shown) that is a vibration damping target. In the following description, in principle, the vertical direction refers to the vertical direction in FIG. In the present embodiment, the vertical direction in FIG. 1 is the vertical direction when the vibration damping device 10 is attached to the vibration member.

  More specifically, the vibration damping device 10 has a housing 12. The housing 12 is made of a material having sufficient rigidity and strength such as metal. In particular, in the present embodiment, in consideration of molding workability, manufacturing cost, and the like, it is formed of, for example, a die cast such as an aluminum alloy or a metal material such as extruded iron. The housing 12 has a substantially rectangular block shape and has a recess 14 that opens vertically downward (downward in FIG. 1), and as a whole, the side wall portions 16a to 16d and the upper bottom wall portion. 17 has a substantially rectangular box shape. In the present embodiment, the inner peripheral surface of the housing 12 is composed of side wall surfaces 18a to 18d.

  In addition, the inner wall surfaces of the lower portion of the side wall portion 16a and the lower portion of the side wall portion 16c in the housing 12 are vertical wall surfaces 20a and 20c, respectively, and the inner wall surfaces of the side wall portion 16b and the side wall portion 16d are respectively full surfaces. The wall surfaces 20b and 20d are spread vertically. On the other hand, the inner wall surfaces of the upper portions of the side wall portions 16a and 16c in the housing 12 each have a quarter-circular arc-shaped curved cross section and have a predetermined length in a horizontal direction substantially parallel to the axial direction of the mass member 28 described later. The curved wall surfaces 22a and 22c are formed to extend. In short, the recess 14 formed in the housing 12 has the wall surfaces 20a and 20c extending vertically and the curved wall surface 22a and the curved wall surface 22c connected to the wall surfaces 20a and 20c, respectively. , 20c and the wall surfaces 20b, 20d extending vertically so as to intersect at right angles, the inner wall surface of the recess 14 is formed by the cooperation of the wall surfaces 20a-d and the curved wall surfaces 22a, 22c. Thereby, the recess 14 is formed so as to extend from the opening side (lower side in FIG. 1) upward in a depth direction with a substantially constant rectangular cross section, and the upper bottom wall surface is a curved surface. The generally formed bowl-shaped recess is formed. In the present embodiment, the upper bottom wall portion 17 of the housing 12 is formed using the upper portions of the side wall portions 16a and 16c, and the side wall surface 18a of the inner peripheral surface of the housing 12 is connected to the wall surface 20a. In addition to the curved wall surface 22a, the side wall surface 18c is composed of the wall surface 20c and the curved wall surface 22c, while the side wall surfaces 18b and 18d are composed of the wall surface 20b and 20d, respectively.

  Further, a spring member 24 is disposed so as to cover the opening of the recess 14. The spring member 24 has a rectangular flat plate shape that spreads on a substantially horizontal plane, and is a metal leaf spring in this embodiment. Such a spring member 24 is fixed to the housing 12 in a cantilever state by one side of the outer peripheral edge portion being superimposed on the lower end surface of the side wall portion 16a constituting the housing 12 and bolted. . Accordingly, the opening of the recess 14 formed in the housing 12 is covered with the spring member 24, and the recess is formed between the opposing surfaces of the housing 12 and the spring member 24 by the cooperation of the housing 12 and the spring member 24. 14 is used to form a storage area 26 as a mass storage space.

  Note that, when the spring member 24 is attached to the housing 12, portions of the outer peripheral edge of the spring member 24 that are not fixed to the housing 12 are slightly separated from the housing 12 in the horizontal direction. Thereby, the vertical displacement is permitted on the free end side of the spring member 24. In particular, in the present embodiment, the lower end surface of the side wall portion 16a of the housing 12 is positioned slightly lower than the lower end surfaces of the other side wall portions 16b to 16d, and the spring member 24 is located on the side wall portion 16b. It is spaced apart in the vertical direction from -d.

  In this embodiment, one mass member 28 is accommodated in the accommodation area 26 of the housing 12 formed in this way. The mass member 28 has a cylindrical shape having a substantially constant circular cross section as a whole, and includes a mass metal fitting 30 as an independent mass member and a covering rubber as an interposed rubber layer formed on the surface of the mass metal fitting 30. Layer 32.

  The mass metal fitting 30 is formed of a metal material having a high specific gravity such as iron, and in the present embodiment, the mass metal fitting 30 has a solid cylindrical shape extending in a substantially constant circular cross section. Note that the mass of the mass member 28 is desirably 1% or more of the mass of the vibration member to which the vibration damping device 10 is attached, and more preferably 3 to 5% of the mass of the vibration member. The If the mass of the mass member 28 is too small with respect to the mass of the vibrating member, it may be difficult to obtain an effective damping effect, while the mass of the mass member 28 is too large with respect to the mass of the vibrating member. This is because the weight of the entire vibration damping device 10 may become a problem.

  On the other hand, the covering rubber layer 32 is formed of a thin rubber elastic body. In this embodiment, the covering rubber layer 32 is formed with a substantially constant wall thickness over the entire outer peripheral surface (surface) of the mass fitting 30, and The surface of the metal fitting 30 is covered. In addition, as the covering rubber layer 32, a layer having a Shore D hardness of 30 or more and 80 or less is preferably used.

  The mass members 28 are accommodated in the accommodating area 26 so as to extend in the horizontal direction, and are not bonded to the housing 12 and the spring member 24, and these housings constituting the wall surface of the accommodating area 26. 12 and the spring member 24 can be independently displaced relative to each other. Further, the accommodating area 26 is configured by a curved surface whose curved wall surfaces 22 a and 22 c have a larger radius of curvature than the mass member 28. Therefore, the storage area 26 is made larger than the mass member 28, and the independent displacement of the mass member 28 is allowed in the storage area 26. In addition, the accommodation area | region 26 in this embodiment is formed so that it may have a fixed cross-sectional shape and may extend in one horizontal direction substantially parallel to the central axis of the mass member 28.

  Further, by placing the mass member 28 on the upper surface of the spring member 24, the spring member 24 fixed in a cantilever state with respect to the housing 12 is elastically bent and deformed by the weight of the mass member 28. Thereby, the free end (the left end in FIG. 1) of the spring member 24 is displaced downward, the spring member 24 is inclined with respect to the horizontal plane, and the mass member 28 is moved by the action of gravity. 1 is biased to the free end side (left side in FIG. 1). Therefore, in the stationary state, the mass member 28 is opposed to the spring member 24 covering the opening of the recess 14 formed in the housing 12 and the side wall surface 18c of the housing 12 positioned on the free end side of the spring member 24. Are brought into contact with each other and separated from the other side wall surfaces 18a, b, d and the curved wall surfaces 22a, 22c by a predetermined distance. Thereby, the mass member 28 is positioned vertically downward with respect to the curved wall surface 22c in the stationary state. The separation distance between the mass member 28 and the side wall surfaces 18a, b, d and the curved wall surfaces 22a, c is preferably set as appropriate according to the amplitude of the vibration to be controlled, thereby more advantageously. The vibration control effect described later can be expressed.

  Further, the mass of the mass member 28 is applied to the spring member 24, and the spring member 24 is bent and deformed, whereby a repulsive force is generated in the spring member 24 in the stationary state. Since the spring member 24 is fixed in a cantilever manner with respect to the housing 12, the repulsive force acts in a direction inclined toward the side wall portion 16c with respect to the vertically upward direction. The repulsive force of the spring member 24 is applied to the mass member 28, whereby a frictional force is applied between the mass member 28 and the housing 12. In the present embodiment, the repulsion direction of the spring member 24 refers to the direction of the repulsive force of the spring member 24 that is applied to the mass member 28 in a stationary state.

  In the present embodiment, the curved wall surface 22 c constituting the upper portion of the side wall surface 18 c on the inner peripheral surface of the housing 12 is inclined with respect to the repulsion direction of the spring member 24. Thereby, the inclined contact surface in the present embodiment is configured as a curved surface continuously curved with a common tangent line by the curved wall surface 22c of the side wall surface 18c.

  The vibration damping device 10 having such a structure is fixedly mounted by bolting the housing 12 to a vibration member (not shown) such as a steering column in an automobile, for example, and integrated with the vibration member. Thus, the housing 12 is displaced by vibration.

  Here, by mounting the vibration damping device 10 having the structure according to the present embodiment on the vibration member, it is possible to advantageously exhibit the vibration damping effect in a wide frequency range. As an example showing such a damping effect, FIGS. 3 to 8 show actual measurement examples of vibration when the damping device 10 is attached to the vibrating member. 3 to 8, the graphs indicated by broken lines show the results of measuring vibrations when the vibration damping device 10 is not attached to the vibration member to be controlled, and are indicated by solid lines. The graph shown shows the result of measuring the vibration with the vibration damping device 10 mounted on the vibration member. According to the actual measurement result obtained in such an actual measurement example, by mounting the vibration damping device 10 on the vibration member, an excellent vibration suppression effect is exhibited for vibrations in a wide frequency range of 30 Hz to 60 Hz. It is clear that

  The reason why such an excellent vibration suppression effect in a wide frequency range can be exhibited is that a plurality of vibration suppression factors are acting in a composite manner. Specifically, for example, a vibration damping action based on energy loss due to friction between the housing 12 and the mass member 28, a vibration damping action (such as a dynamic damper action) by a secondary vibration system including the spring member 24, In addition, the above-described wide or wide as a result of the combined action of a damping action (such as an impact damper action) based on the contact (hit) between the mass member 28 and the housing 12 or the spring member 24. It is considered that the damping effect is exhibited in a plurality of frequency ranges.

  That is, when vibration is generated in the vibration member while the vibration damping device 10 is mounted on the vibration member, the mass member 28 is relatively displaced with respect to the housing 12 in the housing region 26. For example, when the main vibration to be damped is input to the vibration control device 10 in the vertical direction which is the vertical direction in FIG. 1, the mass member 28 is relatively displaced in the vertical vertical direction with respect to the housing 12. . Further, the spring member 24 is elastically deformed according to the relative displacement of the mass member 28 with respect to the housing 12. Accordingly, the mass member 28 is relatively displaced with respect to the vibration member in a state where the mass member 28 is elastically supported by the vibration member via the spring member 24, and the vibration member includes the spring member 24 and the mass member 28. A first sub-vibration system is constructed. And it is thought that an effective damping effect is exhibited based on the resonance action of the first sub-vibration system.

  Further, since the spring member 24 and the mass member 28 are not bonded, and can be independently displaced relative to each other, the contact state between the spring member 24 and the mass member 28 can be changed. That is, for example, when the free end (the left end in FIG. 1) of the spring member 24 is displaced vertically upward, the spring member 24 and the mass member 28 are integrally displaced while being in contact with each other. On the other hand, when the free end of the spring member 24 reaches the top dead center (the upper limit of displacement) and vibrates downward, the spring member 24 and the mass member 28 are separated from each other and are independent of each other. To be displaced. Accordingly, the second sub-vibration system in which the mass of the mass in the mass-spring system is smaller than that of the first sub-vibration system includes the spring member 24. Since the second sub-vibration system has a higher natural frequency than the first sub-vibration system due to a change in mass, it is higher than the natural frequency of the first sub-vibration system. It is considered that an effective damping effect is exerted against the vibration in the frequency range. That is, the vibration damping device 10 has effective vibration damping performance over a wide frequency band ranging from the natural frequency of the first sub-vibration system to the natural frequency of the second sub-vibration system.

  On the other hand, the mass member 28 that is displaced away from the spring member 24 is abutted against the inner peripheral surface of the housing 12. Thereby, the vibration damping effect by the contact | abutting effect | action of the mass member 28 and the housing 12 is exhibited. In particular, in this embodiment, since the mass member 28 comes into contact with the curved wall surface 22c constituting the inclined contact surface, the mass member 28 comes into contact with the housing 12 at a plurality of locations upward ( Hitting).

  Furthermore, the upper part of the side wall surface 18c of the housing 12 is constituted by a curved wall surface 22c, which is an inclined contact surface inclined with respect to the direction in which the repulsive force of the spring member 24 acts. Thus, when the mass member 28 is displaced relative to the housing 12 vertically upward, the mass member 28 is brought into contact with the curved wall surface 22 c of the housing 12. Here, the surface on which the mass member 28 abuts is inclined with respect to the abutting direction of the mass member 28, thereby causing sliding friction or rolling friction between the mass member 28 and the housing 12 (curved wall surface 22 c). In addition, the covering rubber layer 32 constituting the mass member 28 is elastically deformed while maintaining the contact state in the displacement direction (shear direction). Therefore, it is considered that the vibrational effect is exhibited because the input vibration energy is lost by the friction and deformation.

  In particular, in the present embodiment, the spring member 24 is fixed to the housing 12 in a cantilever state so that the free end of the spring member 24 is positioned on the side wall surface 18c side (left side in FIG. 1) having an inclined contact surface. Has been. Then, by placing the mass member 28 on the spring member 24, the mass member 28 is biased to the free end side (left side in FIG. 1) of the spring member 24 using gravity. Therefore, when the mass member 28 is relatively displaced vertically upward with respect to the housing 12 during vibration input, the mass member 28 can be stably brought into contact with the curved wall surface 22c of the housing 12. Yes. Accordingly, it is possible to advantageously obtain the vibration energy attenuation effect by the contact between the mass member 28 and the housing 12, and to effectively exhibit the vibration damping effect. In the present embodiment, the mass member 28 is brought into contact with the side wall surface 18c of the housing 12 by the positioning means using gravity and the repulsive force of the spring member 24 even in a stationary state. Even when a vibration with a minute amplitude is input, a vibration damping effect due to friction between the mass member 28 and the housing 12 is exhibited.

  Further, since the mass member 28 is displaced independently from the spring member 24, the mass member 28 is brought into contact (hit) with the spring member 24 during dropping. Based on the abutting action of the mass member 28 on the spring member 24, the damping effect on the vibration member is effectively exhibited. In particular, in the present embodiment, since a metal leaf spring is employed as the spring member 24, the spring member 24 and the mass member 28 can be separated from each other even when a minute vibration is input. It is thought that the vibration control effect can be obtained effectively. Further, the mass member 28 is separated from the spring member 24 and is jumped and displaced so that the mass member 28 abuts on the inner wall surfaces (the wall surfaces 20a to 20d and the curved wall surfaces 22a and 22c) of the recess 14 at a plurality of locations. It is thought that the effective vibration suppression effect is demonstrated.

  Then, the vibration damping effect (vibration damping action) as described above is applied in a composite or selective manner, so that the vibration damping device 10 according to the present embodiment is mounted on the vibration member, thereby extending over a wide frequency range. It is considered that the vibration damping effect is effectively exhibited, and that the effective vibration damping effect is exhibited even when a minute amplitude vibration is input. Further, in the present embodiment, the vibration suppression effect by constructing the sub-vibration system as described above, the vibration suppression effect by the contact of the mass member 28, and the vibration suppression by friction between the mass member 28 and the housing 12 are also provided. Each of the vibration effects is developed under a plurality of different conditions. That is, a vibration suppression effect due to resonance or the like in a plurality of sub-vibration systems having different mass-spring systems, a vibration suppression effect due to a plurality of hits with different magnitudes and directions of action, and the mass member 28 The damping effect based on damping due to friction between the housing 12 and the elastic deformation in the shear direction of the covering rubber layer 32 can be manifested under different conditions that vary discretely or continuously. Thus, it is considered that the damping effect exhibited by the damping device 10 extends over a plurality of or a wide frequency range.

  Furthermore, in the present embodiment, the mass member 28 is brought into line contact at the boundary between the flange wall surface 20c of the recess 14 formed in the housing 12 and the curved wall surface 22c in the stationary state. Accordingly, even when a minute amplitude vibration is input, the mass member 28 is immediately brought into contact with the curved wall surface 22c formed on the side wall surface 18c. Accordingly, even when a minute amplitude vibration is input, the contact between the housing 12 and the mass member 28 is stably generated, and the damping effect based on the contact (friction) can be effectively exhibited. I can do it.

  Moreover, in this embodiment, while the curved wall surface 22c is comprised by the smooth curved surface, the collar wall surface 20a, the curved wall surface 22a, the curved wall surface 22c, and the collar wall surface 20c are continuously formed by the smooth surface. Accordingly, by adjusting the separation distance between the housing 12 and the mass member 28, for example, when the mass member 28 is displaced upward, friction and contact between the mass member 28 and the curved wall surface 22c, and further, covering Even when the elastic deformation of the rubber layer 32 occurs and the mass member 28 is displaced downward, friction or contact between the mass member 28 and the wall surface 20a or the curved wall surface 22a, and further, the elasticity of the covering rubber layer 32 is achieved. It is possible to cause deformation. According to this, the vibration damping effect by the contact between the inner peripheral surface of the housing 12 and the mass member 28 can be obtained more advantageously. In particular, in this embodiment, the curved wall surfaces 22a and 22c are curved surfaces having a semicircular cross section as a whole, and are smoothly connected to the flange wall surfaces 20a and 20c. Therefore, by appropriately adjusting the separation distance between the housing 12 and the mass member 28 and the curvature of the curved wall surfaces 22a and 22c according to the displacement amplitude of the mass member 28, the mass member 28 is moved along the wall surface of the accommodation region 26. It is also possible to obtain the contact between the inner wall surface (the inner peripheral surface of the housing 12) of the accommodating region 26 and the mass member 28 in a wider range by rotationally displacing. Even when the inclined contact surface is formed of an inclined plane, the inclination angle of the inclined contact surface, the separation distance between the housing 12 and the mass member 28, and the like are appropriately adjusted according to the amplitude of the input vibration. Thus, it is possible to advantageously ensure friction, contact, etc. when the mass member 28 is displaced relative to the housing 12 in both the upper and lower directions.

  Further, in the present embodiment, since the surface of the mass member 28 is entirely covered with the covering rubber layer 32, the frictional resistance between the housing 12 and the mass member 28 is increased, as described above. The energy loss due to friction is increased, and the vibration control effect is more advantageously exhibited. Further, since the covering rubber layer 32 is formed on the surface of the mass member 28, the hitting sound generated when the mass member 28 is abutted against the housing 12 or the spring member 24 is reduced or avoided.

  Further, as described above, in the vibration damping device 10 according to the present embodiment, not only the contact action by the striking against the housing 12 and the spring member 24, and further the vibration member due to the jumping displacement of the mass member 28, but also the housing 12 It is considered that the damping effect is also exerted by the friction of the mass member 28 or the like. Therefore, a stable and effective vibration damping effect is exhibited without setting the separation distance between the housing 12 and the mass member 28 with high accuracy. Accordingly, the separation distance between the housing 12 and the mass member 28 can be set with high accuracy by molding shrinkage of the interposed rubber layer (covered rubber layer 32) formed on at least one of the inner surface of the housing 12 and the outer surface of the mass member 28. Even when it is difficult to set, the desired vibration control effect can be obtained.

  In order to advantageously obtain a plurality of vibration damping effects as described above, it is desirable that the inclination angle α of the inclined contact surface with respect to the rebound direction of the spring member 24 is 5 degrees ≦ | α | ≦ 85 degrees. . Further, the inclination angle: α is more preferably 10 degrees ≦ | α | ≦ 80 degrees, and further preferably 15 degrees ≦ | α | ≦ 60 degrees. The inclination angle of the inclined contact surface with respect to the repulsion direction of the spring member 24: If the absolute value of α is too large, the mass member 28 cannot be brought into contact with the housing 12 so that the mass member 28 slides. It may be difficult to obtain a sufficient vibration damping effect due to friction between the housing 12 and the mass member 28 or elastic deformation of the covering rubber layer 32, and there may be a case where the mass member 28 cannot hit the housing at a plurality of locations. On the other hand, if the absolute value of the inclination angle α is too small, the mass member 28 may not be sufficiently hit against the housing 12, which is based on the contact action of the mass member 28 against the housing 12 or energy loss due to friction. There is a risk that the vibration control effect or the like may not be exhibited effectively. In the case where the inclined contact surface is formed of a curved surface as shown in the present embodiment, the inclination angle α is set by the average of the inclination angles of the tangent to the curved surface with respect to the horizontal plane. It is desirable.

Having thus described the implementation mode of the present invention, which is merely illustrative, the present invention is that the details of the illustrated embodiments, any way, not to be construed as limiting.

For example, in the first embodiment, the example in which the intermediate rubber layer (covered rubber layer 32) is formed on the mass member is shown. However, the intermediate rubber layer is formed on the outer peripheral surface of the independent mass member (mass fitting) and the housing. As long as it is provided on at least one of the inner peripheral surfaces. That is, for example, as in the vibration damping device 42 shown in FIG. 9 , the mass member 44 is formed of a metal solid cylindrical body (mass fitting 30), and an intervening rubber layer is formed on the inner peripheral surface of the housing 12. The covering rubber layer 46 may be provided. In the vibration damping device 42, the recess 14 is formed on the inner peripheral side of the covering rubber layer 46, and the wall surfaces 20 a to 20 d and the curved wall surfaces 22 a and 22 c constituting the recess 14 are formed on the covering rubber layer 46. It consists of an inner peripheral surface. Needless to say, the covering rubber layer 32 may be formed on the surface of the mass member 28, and the covering rubber layer 46 may be formed on the inner peripheral surface of the housing 12.

Further, in the first embodiment, by constituting a part of the side wall surface of the inner peripheral surface of the housing in the curved wall, inclined inclined upper side wall surface of the housing with respect to resilience direction of the spring member The contact surface. However, as the inclined contact surface, at least a part of the inner side surface of the side wall portion only needs to be inclined with respect to the repulsion direction of the spring member, and is necessarily in a curved shape as shown in the embodiment. There is no need. Specifically, for example, a vibration damping device 48 having a contact inclined surface formed as a flat surface as shown in FIG. 10 may be employed. That is, the vibration damping device 48 includes a housing 50, and the housing 50 has a substantially rectangular shape as a whole, and is formed with a recess 52 that opens downward. The recess 52 is a substantially rectangular recess, and each of the housings 50 is substantially flat and has side wall portions 54a to 54d extending in a substantially vertical direction and an upper bottom wall portion 56 extending in a substantially horizontal direction. It is a rectangular box shape. Further, in the side wall surfaces 58a to 58d which are the inner peripheral surfaces of the side wall portions 54a to 54d, the upper surface of the side wall surface 58c is applied as an inclined contact surface formed by an inclined plane inclined with respect to the repulsion direction of the spring member 24. A tangential plane 59 is formed. According to such a vibration damping device 48, it is possible to more advantageously cause the mass member 28 to hit the contact flat surface 59. Therefore, in addition to the vibration damping effect shown in the first embodiment, it is possible to more effectively obtain the vibration damping effect based on the abutting action of the mass member 28 and the housing 50 (the abutting plane 59). I can do it.

Furthermore, the portion (inclined contact surface) that is inclined with respect to the repulsion direction of the spring member on the inner side surface of the side wall portion is not necessarily provided only on the upper portion of the inner side surface of the side wall portion. That is, as in the vibration damping device 60 shown in FIG. 11 , in the side wall portions 64 a to 64 d of the housing 62, the inner side surface of the side wall portion 64 c constituting the recess 66 formed in the housing 62 extends over the entire surface. In this case, the contact plane 68 may be an inclined contact surface constituted by a single inclined plane. According to this, the abutting state of the mass member 28 and the abutting plane 68 can be realized more advantageously, and the vibration damping effect due to the friction between the mass member 28 and the housing 62 can be stably obtained. I can do it. In addition, it may be possible to advantageously exhibit a damping effect especially when a minute amplitude vibration is input. In the housing, the same effect as that of the above-described vibration damping device 60 can also be obtained by configuring the inner side surface of the side wall portion on which the independent mass member is brought into contact with the gravity by a smooth curved surface over the entire surface. Can be obtained. Further, the entire inner wall surface of the recess formed in the housing may be constituted by a single curved surface.

Moreover, as a spring member, the example which employ | adopts a metal leaf | plate spring in said 1st embodiment was shown . However, the spring member is not limited in any way by the description in the first embodiment.

  In addition, the independent mass member is preferably formed in a cylindrical shape (a rod shape having a circular cross section) from the viewpoint of effectively generating energy loss due to contact with the housing, but has a spherical or elliptical cross section. You may employ | adopt the independent mass member made into the other shape which has circular cross sections, such as column shape. Moreover, when it is formed so as to extend over a predetermined length with a cross-sectional shape such as a circular cross-section or an elliptical cross-section (circular rod shape or the like), it needs to be formed so as to necessarily extend with a constant cross-sectional shape. The cross-sectional shape may be changed in the axial direction. For example, in an independent mass member having a rod shape extending in a circular cross section, by changing the diameter of the cross section in the axial direction, the contact area between the independent mass member and the housing or the spring member is adjusted, thereby generating a hitting sound. It can also be reduced. In addition, when employ | adopting the independent mass member of another shape as mentioned above, it is desirable to change suitably the inner peripheral surface shape of a housing, ie, the shape of a mass accommodation space, according to the shape of an independent mass member.

The housing is not necessarily formed separately from the vibration member, and may be formed integrally with the vibration member. Furthermore, the outer shape of the housing is not limited by the specific shape described in the first embodiment.

Further, the shape of the recess formed in the housing is not limited in any way by the specific shape described in the first embodiment. Specifically, for example, a recess having an upper bottom wall surface extending in an elliptical cross section or a recess having a spherical shell inner wall surface can be employed. Note that the cross-sectional shape of the recess is not necessarily constant, and may be formed to extend by a predetermined length while changing the cross-sectional shape.

  Also, it is not necessary that only one recess is formed for one housing. Specifically, for example, two or more recesses are formed in one housing, and each spring member is arranged in a cantilever state so as to cover each opening of the recesses. In addition, one independent mass member may be arranged in a accommodated state in each of a plurality of accommodating areas formed by a plurality of recesses. In addition, by making the shape of the recess, the mass and shape of the independent mass member accommodated, or the spring constant of the spring member, etc. different for each recess, the damping effect in a wider frequency range is more advantageous. It is also possible to achieve this.

  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 a longitudinal cross-sectional view which shows the vibration damping device as 1st embodiment of this invention, Comprising: The II sectional view taken on the line in FIG. It is a longitudinal cross-sectional view which shows the damping device shown by FIG. 1, Comprising: The II-II sectional view taken on the line in FIG. The actual measurement example which shows the damping effect of the damping device shown by FIG. The actual measurement example which shows the damping effect of the damping device shown by FIG. The actual measurement example which shows the damping effect of the damping device shown by FIG. The actual measurement example which shows the damping effect of the damping device shown by FIG. The actual measurement example which shows the damping effect of the damping device shown by FIG. The actual measurement example which shows the damping effect of the damping device shown by FIG. The longitudinal cross-sectional view which shows another one Embodiment of this invention. The longitudinal cross-sectional view which shows another one Embodiment of this invention. The longitudinal cross-sectional view which shows another one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Damping device, 12 Housing, 14 Recessed part, 16 Side wall part, 18 Side wall surface, 22 Curved wall surface, 24 Spring member, 26 Storage area | region, 28 Mass member, 30 Mass metal fitting, 32 Covering rubber layer

Claims (5)

In the rigid housing fixedly provided on the vibration member to be damped, a recess that opens downward is formed, and a spring member that covers the opening of the recess is provided to form a mass accommodation space. The independent mass member having a circular cross section is accommodated in the mass accommodating space so as to be independently displaceable without being bonded, while the relative contact between at least one of the outer peripheral surface of the independent mass member and the inner peripheral surface of the housing is relatively small. An intervening rubber layer is deposited on the contact portion, and at least a part of the side wall surface of the inner peripheral surface of the housing is an inclined contact surface that is inclined with respect to the repulsion direction of the spring member ;
The spring member includes a leaf spring formed of a metal material, the leaf spring is fixed to the housing in a cantilever manner, and a free end of the leaf spring is connected to the housing. The vibration damping device according to claim 1, wherein the vibration damping device is positioned on the side of the side wall surface on which the inclined contact surface of the mass accommodating space is provided .   The vibration damping device according to claim 1, wherein the independent mass member has a circular cross section and a cylindrical shape extending in a horizontal direction.   3. The bottom wall surface of the mass accommodating space formed by the spring member is inclined downward toward the side wall surface having the inclined contact surface under a stationary state. Damping device.   The inclined contact surface is formed of a curved surface that continuously curves with a common tangent, and the curvature radius of the curved surface is larger than the curvature radius of the surface of the mass member. The damping device as described in any one of thru | or 3. The vibration damping device according to any one of claims 1 to 4 , wherein the spring member includes a rubber elastic plate.

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