JP2006312984A - Dynamic damper and mounting structure of dynamic damper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dynamic damper facilitating mounting work and a mounting structure of the dynamic damper. <P>SOLUTION: A pair of turning prevention pins 13 provided to a first bracket 3a and a second bracket 3b are arranged at a point symmetric position from each other taking as a reference the intersection O between the center line lz of a mass member 2 parallel to the Z direction and the center line lx of a mass member 2 parallel to the X direction so that no directivity in the Z and X directions is generated in a damper 1. When a pair of turning prevention pins 13 are fitted to a recess 23 provided to a supporting part 20 in advance at mounting of the damper 1, no confirmation of directivity in the Z and X directions of the dynamic damper 1 is required, thereby facilitating the mounting work. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a dynamic damper and a dynamic damper mounting structure, and more particularly to a dynamic damper and a dynamic damper mounting structure that facilitate mounting.

  Conventionally, various dynamic dampers have been used in vehicles in order to reduce harmful vibrations generated from an engine, a rotating shaft, and the like. This dynamic damper can effectively reduce the harmful vibration by tuning the resonance frequency (natural frequency) in accordance with the peak frequency of the harmful vibration in question.

  In recent years, seats mounted on vehicles have been diversified, and seat vibration problems have occurred due to lack of rigidity and the like. Dynamic dampers are being used.

  FIG. 6 shows a specific example thereof, and is a diagram showing a vehicle seat 200 and a dynamic damper 202 attached to a seat back 201. As shown in detail in FIG. 7, the dynamic damper 202 includes a mass member 204 that is one lump having a large mass, and a vibration-proof base 206 composed of a pair of upper and lower rubber-like elastic bodies. The dynamic damper 202 has a structure that suppresses harmful vibration generated in the seat back 201 of the vehicle by a resonance operation of a vibration system constituted by the mass member 204 and the vibration isolation base 206.

The dynamic damper 202 is attached to the seat back 201 of the vehicle via a bracket 210 having a pair of upper and lower attachment portions 208. A bolt hole 209 is formed in the center of each of the pair of upper and lower mounting portions 208. The bracket 210 is superimposed on the mounting position of the seat back 201 of the vehicle, and is fixed to the seat back 201 with a fixing bolt inserted into the bolt hole 209. When attaching the bracket 210 to the seat back 201 of the vehicle, the pair of protrusions 211 provided in the vicinity of the bolt holes 209 are fitted into recesses provided in advance on the dynamic damper mounting surface of the vehicle seat back 201. Do it. Thereby, the bracket 210 is positioned at the mounting position of the seat back 201 of the vehicle, and further, the movement of the bracket 210 is suppressed after the positioning, so that the fixing bolt inserted into the bolt hole 209 can be fastened stably.
JP 2004-245314 A

  However, as shown in FIG. 7, in the conventional dynamic damper 202, the protrusion 211 is provided at a symmetrical position in the vertical direction (Z direction) of the dynamic damper 202, but in the horizontal direction (X direction). It was provided to be in the same position. For example, in the example shown in FIG. 7, a pair of protrusions 211 is provided on one side in the left-right direction (X direction) of the dynamic damper 202 (left direction in FIG. 7). Therefore, directionality has occurred in the dynamic damper 202. As a result, the direction of the dynamic damper 202 is set so that the right and left direction of the dynamic damper is correct so that the recess 211 provided in the seat back 201 of the vehicle and the protrusion 211 are fitted during the mounting operation. There is a problem that the installation work becomes complicated.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a dynamic damper and a dynamic damper mounting structure that can be easily mounted.

  In order to achieve this object, the dynamic damper according to claim 1 connects a mass member as a mass body, a bracket attached to a support portion of a seat back of a vehicle seat, the bracket and the mass member. An anti-vibration base composed of a rubber-like elastic body, wherein the bracket is connected to one side in the first direction of the mass member and the other in the first direction of the mass member. The first bracket and the second bracket are at least a pair of bracket-side fitting portions that are fitted with at least a pair of support-side fitting portions provided in the support portion. The at least one pair of bracket-side fitting portions are flat in a second direction perpendicular to the first direction and a center line of the mass member parallel to the first direction. They are arranged in point symmetrical positions to each other relative to the intersection of the center line of a mass member.

  The dynamic damper according to claim 2 is the dynamic damper according to claim 1, wherein the bracket-side fitting portion is formed by a protrusion, and the support-side fitting portion provided in the support portion is the bracket-side fitting portion. It is comprised by the hollow which fits.

  The dynamic damper according to claim 3 is the dynamic damper according to claim 1 or 2, wherein the first bracket and the second bracket attach and fix the first bracket and the second bracket to the support portion. And at least a pair of through holes provided in the first bracket and the second bracket are arranged at point symmetrical positions with respect to the intersection. Yes.

  A dynamic damper according to a fourth aspect is the dynamic damper according to any one of the first to third aspects, wherein the first bracket and the second bracket are separated from each other.

  6. The dynamic damper mounting structure according to claim 5, wherein a mass member as a mass body, a bracket attached to a support portion of a seat back of a vehicle seat, the bracket and the mass member, and a rubber-like elastic body are connected. A dynamic damper comprising a vibration isolating base comprising: a first bracket coupled to one of the mass members in a first direction; A second bracket connected to the other of the mass members in the first direction, and at least a pair of bracket-side fitting portions provided on the first bracket and the second bracket; and provided on the support portion. And at least a pair of bracket side fitting portions and a support portion side fitting portion to be fitted. The side fitting portions are arranged at point symmetrical positions with respect to an intersection of a center line of the mass member parallel to the first direction and a center line of the mass member parallel to the second direction perpendicular to the first direction. ing.

  The dynamic damper mounting structure according to claim 6 is the dynamic damper mounting structure according to claim 5, wherein the bracket side fitting portion is constituted by a protrusion, and the support portion side fitting portion provided in the support portion is It is comprised by the hollow fitted with the said bracket side fitting part.

  The dynamic damper mounting structure according to claim 7 is the dynamic damper mounting structure according to claim 5 or 6, wherein the dynamic damper mounting structure is provided on the first bracket and the second bracket, and the first bracket and the second bracket are connected to each other. At least a pair of through-holes through which a fixing member for attaching and fixing to the support portion is inserted, and at least a pair of attachment holes provided in the support portion and inserted through the through-hole and through which the fixing member is inserted. The at least one pair of through-holes are arranged at point-symmetric positions with respect to the intersection.

  The dynamic damper mounting structure according to claim 8 is the dynamic damper mounting structure according to any one of claims 5 to 7, wherein the first bracket and the second bracket are separated from each other.

  According to the dynamic damper of claim 1, the first bracket and the second bracket are at least a pair of bracket side fitting portions that are fitted to at least a pair of support portion side fitting portions provided in the support portion. The first bracket and the second bracket are positioned with respect to the support portion by fitting the pair of bracket side fitting portions and the pair of support portion side fitting portions. The first bracket and the second bracket are restrained from moving relative to the support portion.

  Here, at least a pair of bracket-side fitting portions provided on the first bracket connected to one of the mass members in the first direction and the second bracket connected to the other of the mass members in the first direction are: , Since the center line of the mass member parallel to the first direction and the center line of the mass member parallel to the second direction perpendicular to the first direction are arranged at point-symmetrical positions with respect to each other, dynamic The damper does not cause the first direction and the second direction. Therefore, when attaching the dynamic damper to the support portion, there is no need to confirm the directivity of the dynamic damper in the first direction and the second direction, and there is an effect that the attaching operation becomes easy.

  According to the dynamic damper of the second aspect, in addition to the effect produced by the dynamic damper of the first aspect, the bracket side fitting portion is configured by a protrusion, and the support portion side fitting portion provided in the support portion is Since it is composed of a recess that fits with the bracket-side fitting portion, the movement of the protrusion that constitutes the bracket-side fitting portion is regulated by the inner surface of the recess that constitutes the support-side fitting portion, and the surface of the support portion Movement in the direction along is suppressed. Therefore, since the movement of the first bracket and the second bracket with respect to the support portion is surely suppressed, there is an effect that the attaching operation becomes easier.

  According to the dynamic damper according to claim 3, in addition to the effect produced by the dynamic damper according to claim 1 or 2, at least a pair of through holes provided in the first bracket and the second bracket are based on the intersection. As described above, when the dynamic damper is attached to the support portion, it is not necessary to confirm the directionality of the dynamic damper in the first direction and the second direction, and the attaching operation is facilitated. effective.

  According to the dynamic damper of the fourth aspect, in addition to the effect produced by the dynamic damper according to any one of the first to third aspects, the first bracket and the second bracket are separated from each other. The effect of the pair of bracket-side fitting portions, which suppresses the movement of the first bracket and the second bracket and facilitates the mounting operation, is particularly remarkable. This is because when the first bracket and the second bracket are separated from each other, movement is more likely to occur than when they are integrated.

  In addition, since the first bracket and the second bracket are both connected to the mass member via the vibration isolation base, vibration is input to the seat back of the vehicle seat, and the mass bracket and the vibration isolation base are configured. When the vibration system is resonated, the vibration is applied from the vibration-proof substrate. Here, when the first bracket and the second bracket are separated from each other, compared to the case where the bracket is integrally formed, the first bracket and the second bracket are more easily affected by vibration from the vibration-isolating base, and each of them is rotated. Shaking such as movement and swinging is likely to occur. Therefore, by providing a pair of bracket-side fitting portions to be fitted to the pair of support portion-side fitting portions on the first bracket and the second bracket, and suppressing movement of the first bracket and the second bracket with respect to the support portion. Even when the first bracket and the second bracket are separated from each other, there is an effect that the occurrence of rattling such as rotation or swinging at the time of vibration input is suppressed.

  In addition, when the input vibration is particularly large, the mass member vibrates greatly and hits the bracket, and a hitting sound may be generated, but by separating the first bracket and the second bracket from each other, As compared with the case where the first bracket and the second bracket are integrally formed, there is an effect that the hitting sound can be reduced.

  Moreover, since at least a pair of bracket side fitting parts are arrange | positioned at a 1st bracket and a 2nd bracket so that it may become a point symmetrical position mutually on the basis of the said intersection, as a 1st bracket and a 2nd bracket The same shape can be used, and there is an effect that the types of brackets are reduced by half, and the management becomes easy.

  According to the dynamic damper mounting structure according to claim 5, at least a pair of bracket side fitting portions provided on the first bracket and the second bracket, and at least the pair of bracket side fittings provided on the support portion. Since the fitting portion and the supporting portion side fitting portion are provided, the first bracket and the supporting portion are fitted to each other by fitting the pair of bracket side fitting portions and the pair of supporting portion side fitting portions. The second bracket is positioned, and after the positioning, the movement of the first bracket and the second bracket relative to the support portion is suppressed.

  Here, at least a pair of bracket-side fitting portions provided on the first bracket connected to one of the mass members in the first direction and the second bracket connected to the other of the mass members in the first direction are: , Since the center line of the mass member parallel to the first direction and the center line of the mass member parallel to the second direction perpendicular to the first direction are arranged at point-symmetrical positions with respect to each other, dynamic The damper does not cause the first direction and the second direction. Therefore, when attaching the dynamic damper to the support portion, there is no need to confirm the directivity of the dynamic damper in the first direction and the second direction, and there is an effect that the attaching operation becomes easy.

  According to the dynamic damper mounting structure of claim 6, in addition to the effect exhibited by the dynamic damper mounting structure of claim 5, the bracket-side fitting portion is constituted by a protrusion, and the support provided on the support portion. Since the part-side fitting part is constituted by a depression that fits with the bracket-side fitting part, the movement of the protrusion that constitutes the bracket-side fitting part is regulated by the inner surface of the depression that constitutes the support part-side fitting part. The movement in the direction along the surface of the support portion is suppressed. Therefore, since the movement of the first bracket and the second bracket with respect to the support portion is surely suppressed, there is an effect that the attaching operation becomes easier.

  According to the dynamic damper mounting structure according to claim 7, in addition to the effect of the dynamic damper mounting structure according to claim 5 or 6, at least a pair of through holes provided in the first bracket and the second bracket. Are arranged in a point-symmetrical position with respect to the intersection point, so that it is not necessary to confirm the directionality of the dynamic damper in the first direction and the second direction when attaching the dynamic damper to the support portion. There is an effect that the work becomes easy.

  According to the dynamic damper mounting structure of the eighth aspect, in addition to the effect of the dynamic damper mounting structure according to any one of the fifth to seventh aspects, the first bracket and the second bracket are separated from each other. Therefore, the effect by a pair of bracket side fitting part of suppressing the movement of the 1st bracket and the 2nd bracket with respect to a support part, and facilitating attachment work is acquired notably. This is because when the first bracket and the second bracket are separated from each other, movement is more likely to occur than when they are integrated.

  In addition, since the first bracket and the second bracket are both connected to the mass member via the vibration isolation base, vibration is input to the seat back of the vehicle seat, and the mass bracket and the vibration isolation base are configured. When the vibration system is resonated, the vibration is applied from the vibration-proof substrate. Here, when the first bracket and the second bracket are separated from each other, compared to the case where the bracket is integrally formed, the first bracket and the second bracket are more easily affected by vibration from the vibration-isolating base, and each of them is rotated. Shaking such as movement and swinging is likely to occur. Therefore, by providing a pair of bracket-side fitting portions to be fitted to the pair of support portion-side fitting portions on the first bracket and the second bracket, and suppressing movement of the first bracket and the second bracket with respect to the support portion. Even when the first bracket and the second bracket are separated from each other, there is an effect that the occurrence of rattling such as rotation or swinging at the time of vibration input is suppressed.

  In addition, when the input vibration is particularly large, the mass member vibrates greatly and hits the bracket, and a hitting sound may be generated, but by separating the first bracket and the second bracket from each other, As compared with the case where the first bracket and the second bracket are integrally formed, there is an effect that the hitting sound can be reduced.

  Moreover, since at least a pair of bracket side fitting parts are arrange | positioned at a 1st bracket and a 2nd bracket so that it may become a point symmetrical position mutually on the basis of the said intersection, as a 1st bracket and a 2nd bracket The same shape can be used, and there is an effect that the types of brackets are reduced by half, and the management becomes easy.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings. FIG. 1 is a bottom view of a dynamic damper 1 according to an embodiment of the present invention, FIG. 2 is a side view of the dynamic damper 1, and FIG. 3 is a top view of the dynamic damper.

  The dynamic damper 1 is attached to a seat back of a vehicle seat and is a vibration isolator for suppressing vibration of the seat back. As shown in FIGS. 1 to 3, a mass member 2 as a mass body, It mainly includes a bracket 3 attached to a seat back of a vehicle seat, and an anti-vibration base 4 that connects the bracket 3 and is made of a rubber-like elastic body. The mounting position of the dynamic damper 1 on the seat back is the same as that of the conventional dynamic damper shown in FIG.

  The mass member 2 includes a rectangular block-shaped metal mass body 2a having a rectangular surface in a plan view shown in FIG. 1, a metal receiving surface member 2b welded to a side surface of the mass body 2a, and the mass member 2a. It consists of the main rubber | gum 2a and the covering rubber layer 14 which coat | covers the surface of the receiving surface member 2b, and has predetermined mass m.

  Hereinafter, in the plan view shown in FIG. 1 and FIG. 3, the short side direction (left and right direction in FIG. 1) of the rectangular surface of the mass body 2a is referred to as the X direction, and the long direction (up and down direction in FIG. 1) is the Z direction. Called. The direction perpendicular to the X direction and the Z direction (the direction perpendicular to the plane of FIG. 1) is referred to as the Y direction (see FIG. 2). The dynamic damper 1 is attached to a vehicle seat back such that the X direction corresponds to the left-right direction of the vehicle, the Y direction corresponds to the front-rear direction of the vehicle, and the Z direction corresponds to the up-down direction of the vehicle. The Z direction corresponds to the first direction of the claims, and the X direction corresponds to the second direction of the claims.

  Further, as shown in FIG. 2, the mass member 2 includes a pair of wide surfaces 5 perpendicular to the Y direction, and a side surface portion 6 connecting the pair of wide surfaces 5. The side surface portion 6 includes a side surface 6a that is perpendicular to the pair of wide surfaces 5, and an inclined portion 6b that protrudes from both end sides in the Z direction of one wide surface 5 and that is parallel to the X direction and inclined with respect to the Y direction. Have. The inclined portion 6b is provided with a receiving surface 7 to which one end of the vibration isolating base 4 is connected.

  As shown in FIG. 2, the bracket 3 includes a first bracket 3a and a second bracket 3b that are separated from each other. Here, “separated from each other” means a state in which the surfaces are separated from each other and the surfaces are not in contact with each other. The first bracket 3a and the second bracket 3b have the same shape as each other. As shown in FIG. 1, in the dynamic damper 1, the first bracket 3a is connected to one side of the mass member 2 in the Z direction. The second bracket 3b is connected to the other side of the member 2 in the Z direction. Moreover, the 1st bracket 3a and the 2nd bracket 3b have the 1st direction control board 9, the upright part 10, and the attaching part 11, respectively, integrally.

  The first direction restricting plate 9 is a plate-like member perpendicular to the Y direction that is spaced from and opposed to the end portion in the Z direction on one wide surface 5 of the mass member 2. The first direction regulating plate 9 regulates the amount of relative displacement of the mass member 2 with respect to the bracket 3 in the Y direction.

  The upright portion 10 is a member that rises from the end portion of the first direction regulating plate 9 along the side surface portion 6 of the mass member 2. Further, the upright portion 10 is an end portion on the first direction regulating plate 9 side, which is a support wall portion 10a that is parallel to the X direction and inclined with respect to the Y direction, and an end portion on the opposite side to the first direction regulating plate 9 The connecting portion 10b is parallel to the X direction and the Y direction. The support wall 10a is provided with a support surface 10c to which the other end of the vibration isolating base 4 is connected (see FIG. 2). The upright portion 10 regulates the relative displacement amount of the mass member 2 with respect to the bracket 3 in the Z direction.

  The attachment portion 11 extends from the end of the upright portion 10 opposite to the first direction restricting plate 9, and a through hole 12 and a rotation prevention pin 13 are formed. As will be described later with reference to FIG. 5, the first bracket 3 a and the second bracket 3 b are attached to the seat back support portion 20 of the vehicle seat by a fixing bolt 21 a and a nut 21 b inserted through the through hole 12. .

  Here, as shown in FIG. 3, the pair of through-holes 12 and the pair of rotation prevention pins 13 include the center line 1z of the mass member 2 parallel to the Z direction and the center line lx of the mass member 2 parallel to the X direction. The first bracket 3a and the second bracket 3b are provided so as to be point-symmetrical with respect to the intersection point O. In addition, the further structure of the through-hole 12 and the rotation prevention pin 13 is demonstrated in detail later with reference to FIG.

  In the present embodiment, the thin covering rubber layer 14 is attached to the mass member 2 and the bracket 3 to cover the entire outer peripheral surface of the mass member 2 and a part of the bracket 3. The vibration-proof substrate 4 is formed integrally with the rubber layer 14. That is, the covering rubber layer 14 and the vibration isolating base 4 are formed by injection-filling a rubber material into the molding cavity and vulcanizing it with the mass member 2 and the bracket 3 positioned and set in a molding cavity of a predetermined molding die. At the same time as the vulcanization molding, the mass member 2 and the bracket 3 are vulcanized and bonded.

  The anti-vibration base 4 connects the receiving surface 7 provided on the mass member 2 and the support surface 10 c provided on the bracket 3. The dynamic damper 1 tunes the resonance frequency of the vibration system composed of the mass member 2 and the vibration isolation base 4 in accordance with the peak frequency of harmful vibration that occurs in the seat back, thereby causing harmful vibration that occurs in the seat back. Can be effectively reduced.

  The resonance frequency of the vibration system is determined based on Equation 1 above. More specifically, the resonance frequency fx in the X direction is tuned based on the spring constant kx in the X direction of the vibration isolation base 4 and the mass m of the mass member 2, and the resonance frequency fy in the Y direction is 4 is tuned based on the Y-direction spring constant ky and the mass m of the mass member 2. Since the mass m of the mass member 2 is common, in order to increase the resonance frequency fy in the Y direction compared to the resonance frequency fx in the X direction, the Y direction with respect to the spring constant kx in the X direction of the vibration isolation base 4 It is necessary to increase the ratio of the spring constant ky.

  Since the receiving surface 7 and the support surface 10c to which the vibration isolating base 4 is connected are parallel to the X direction, when the mass member 2 is relatively displaced in the X direction with respect to the bracket 3, the vibration isolating base 4 is subjected to shear deformation. It is. On the other hand, the receiving surface 7 and the support surface 10c are inclined with respect to the Y direction, and the anti-vibration base 4 is connected so that the receiving surface 7 and the support surface 10c overlap each other when viewed from the Y direction. Therefore, when the mass member 2 is relatively displaced in the Y direction with respect to the bracket 3, the vibration isolation base 4 connected to the receiving surface 7 and the support surface 10 c is subjected to compression or tensile deformation.

  Therefore, the ratio of the spring constant ky in the Y direction to the spring constant kx in the X direction of the vibration isolation base 4 becomes large. As a result, in the vibration system composed of the mass member 2 and the vibration isolation base 4, the resonance frequency in the Y direction is set to a frequency range larger than the resonance frequency in the X direction while tuning the resonance frequency in the X direction to a predetermined frequency range. Can be tuned. For example, when the peak frequency of harmful vibration generated in the X direction in the seat back is 19 Hz and the peak frequency of harmful vibration generated in the Y direction is 29 Hz, the ratio of the peak frequency in the Y direction to the X direction is about 1. Since the spring ratio (ky / kx) of the anti-vibration base 4 is about 1.5, the resonance frequency of the vibration system composed of the mass member 2 and the anti-vibration base 4 is 19 Hz in the X direction, Y Tune to 29Hz in the direction. As a result, the dynamic damper 1 can simultaneously reduce harmful vibration in a predetermined frequency range that occurs in the X direction and harmful vibration that occurs in the Y direction in a frequency range that is greater than the resonance frequency in the X direction.

  The receiving surface 7 provided on the mass member 2 and the support surface 10c provided on the bracket 3 are configured in parallel to each other. Thereby, when the mass member 2 is relatively displaced with respect to the bracket 3, it is possible to suppress the strain distribution in the vibration isolating base 4 from becoming non-uniform and to concentrate the strain on the portion, thereby ensuring durability. .

  Further, the receiving surface 7 is provided on the side surface portion 6 (inclined portion 6 b) of the mass member 2, and the support surface 10 c is the end of the rising portion 10 rising toward the side surface portion 6 of the mass member 2 on the first direction regulating plate side 9. Since it is provided in the portion, the dynamic damper 1 can be prevented from being enlarged in the Y direction.

  That is, as in the dynamic damper 1 of the present embodiment, in order to increase the ratio of the spring constant ky in the Y direction to the spring constant kx of the vibration isolation base 4, for example, the wide surface 5 of the mass member 2 and its wide width It is conceivable to connect the anti-vibration base 4 between the first direction regulating plate 9 facing the surface 5 and perpendicular to the Y direction. However, with this configuration, it is necessary to provide a large gap between the wide surface 5 of the mass member 2 and the first direction regulating plate 9 of the bracket 3 so that the vibration isolating base 4 is interposed. Increasing the size in the Y direction (front-rear direction of the vehicle) is unavoidable, and is not preferable as being attached to the seat back.

  On the other hand, according to the dynamic damper 1 of the present embodiment, the receiving surface 7 provided on the side surface portion 6 of the mass member 2, and the support surface 10 c provided on the rising portion 10 rising toward the side surface portion 6. Since the anti-vibration base 4 is interposed therebetween, the dynamic damper 1 can be prevented from increasing in size in the Y direction (the longitudinal direction of the vehicle).

  Further, in the bracket 3, the upright portion 10 provided between the first direction restricting plate 9 and the attachment portion 11 is effectively used, and the end portion of the upright portion 10 on the first direction restricting plate 9 side in the Y direction. Since the support surface 10c (support wall portion 10a) is provided by being inclined with respect to the X direction, no new space or member is required to provide the support surface 10c, and the dynamic damper 1 is compact. And it can be advantageous in terms of cost.

  Next, the mass body 2a and the receiving surface member 2b constituting the mass member 2 will be described in detail with reference mainly to FIG. The mass body 2a is configured in a rectangular block shape, and a receiving surface member 2b is welded to a pair of side surfaces parallel to the XY plane.

  The receiving surface member 2b is a member having a circumscribed surface 2c attached to the side surface of the mass body 2a and a receiving surface constituting surface 2d that is inclined at a predetermined angle with respect to the Y direction and parallel to the X direction. The receiving surface constituting surface 2d is bent with respect to 2c. In addition, the inclined part 6b is formed in the side part 6 of the mass member 2 by the receiving surface member 2b. The receiving surface constituting surface 2d forms a receiving surface 7 that is inclined at a predetermined angle with respect to the Y direction and parallel to the X direction.

  With reference to FIG. 4, the relationship between the angle θ of the receiving surface 7 with respect to the Y direction and the spring constant k of the vibration isolation base 4 will be described. FIG. 4A is an enlarged view of the side surface portion 6 of the mass member 2 and shows a state in which the receiving surface 7 is inclined at an angle θ1 with respect to the Y direction. FIG. 4B is an enlarged view of the side surface portion 6 of the mass member 2, and shows a state in which the receiving surface 7 is inclined at an angle θ2 (θ2> θ1) with respect to the Y direction.

  As shown in FIG. 4, the larger the angle θ of the receiving surface 7 and the support surface 10c with respect to the Y direction, the greater the proportion of the compression or tension component in the elastic deformation of the vibration isolating substrate 4 in the Y direction. The spring constant ky in the direction is higher than the spring constant kx in the X direction. That is, by adjusting only the angle θ with respect to the Y direction while keeping the receiving surface 7 and the support surface 10c parallel to the X direction, only the spring constant ky in the Y direction can be changed without changing the spring constant kx in the X direction. It can be.

  Therefore, when tuning the dynamic damper 1 of the present embodiment, first, the volume and rigidity of the vibration-proof base 4 are selected so that the resonance frequency fx in the X direction becomes a desired frequency. Thereafter, by adjusting only the angle θ with respect to the Y direction while keeping the receiving surface 7 and the support surface 10c parallel to the X direction, the resonance frequency fy in the Y direction can be set to a desired value without changing the resonance frequency fx in the X direction. Can be tuned to frequency.

  Further, according to the dynamic damper 1 of the present embodiment, the mass body 2a and the receiving surface member 2b are separate from each other. Therefore, only the receiving surface member 2b is replaced during tuning, so that the receiving surface 7 The resonance frequency fy in the Y direction can be tuned by changing the angle θ with respect to the Y direction. On the other hand, as the mass body 2a, a rectangular block that is easily available can be used in common, which is advantageous in terms of cost. When the receiving surface member 2b is not provided as a separate body but is provided integrally with the mass body 2a, a plurality of types of mass bodies 2a with different angles of the receiving surface 7 must be prepared. Cost.

  In addition, as the mass main body 2a, a rectangular block shape that is easily available can be used in common, so that a plurality of types in which the angle of the receiving surface 7 with respect to the Y direction is adjusted according to the target resonance frequency. In the case of producing a small amount of each of these dynamic dampers, it is advantageous in terms of cost. This is because, in order to process the mass body 2a integrally provided with the inclined portion 6b for constituting the receiving surface 7, a plurality of molds are required, or separate processes such as thermal forging and cold forging are required.

  With reference to FIG. 5, the attachment structure of the dynamic damper 1 of this embodiment is demonstrated. FIG. 5 is a cross-sectional view showing a cross section perpendicular to the X direction of the support portion 20 of the seat back and the dynamic damper 1 attached to the support portion 20. Here, the support part 20 is a member fixed to the seat back of the vehicle.

  As shown in FIG. 5, each of the first bracket 3a and the second bracket 3b is provided with a through hole 12 penetrating in the Y direction. Fixing bolts 21 for attaching and fixing the first bracket 3a and the second bracket 3b to the support portion 20 are inserted into the pair of through holes 12 provided in the first bracket 3a and the second bracket 3b. The On the other hand, the support portion 20 is provided with a pair of mounting holes 22 through which the fixing bolts 21a inserted through the through holes 12 are inserted.

  A nut 21 b is screwed onto the fixing bolt 21 a inserted through the through hole 12 and the mounting hole 22 on the back side of the support portion 20. Thereby, the 1st bracket 3a and the 2nd bracket 3b, and the support part 20 are fastened.

  Further, as shown in FIG. 5, in order to position the first bracket 3a and the second bracket 3b with respect to the support portion 20, the surface of the first bracket 3a and the second bracket 3b facing the support portion 20 is not provided. A rotation prevention pin 13 is provided. The rotation prevention pin 13 is configured by a protrusion protruding toward the support portion 20 side.

  On the other hand, in order to position the first bracket 3a and the second bracket 3b with respect to the support portion 20, the support portion 20 has a pair of rotation prevention pins provided on the first bracket 3a and the second bracket 3b, respectively. A pair of depressions 23 to be fitted with 13 is provided in advance.

  When the first bracket 3a and the second bracket 3b of the dynamic damper 1 configured as described above are attached to the support portion 20 fixed to the seat back of the vehicle, prior to fastening by the fixing bolt 21a and the nut 21b. The pair of anti-rotation pins 13 provided on the first bracket 3a and the second bracket 3b are engaged with the recesses 23 provided in advance in the support unit 20.

  Thereby, the 1st bracket 3a and the 2nd bracket bracket 3b of the dynamic damper 1 can be easily positioned in the attachment position with respect to the support part 20 fixed to the seat back of the vehicle. Further, after the positioning, the movement of the rotation prevention pin 13 is restricted by the inner surface of the recess 23 and the movement in the direction along the surface of the support 20 is suppressed, so that the dynamic damper 1 moves relative to the support 20. Is reliably suppressed. Therefore, in the positioned state, it is possible to stably perform the operation of inserting the fixing bolt 21a through the through hole 12 and the mounting hole 22 and screwing the nut 21b into the fixing bolt 21a. Therefore, the attachment work becomes easy. In particular, in the dynamic damper 1 of the present embodiment, since the bracket 3 is separated into the first bracket 3a and the second bracket 3b, the movement is likely to occur as compared with the case where the bracket 3 is integrated. Therefore, the effect by the rotation prevention pin 13 is remarkable.

  Here, as described with reference to FIGS. 1 to 3, the pair of anti-rotation pins 13 provided on the first bracket 3 a and the second bracket 3 b are formed by the mass member 2 parallel to the Z direction. Since the center line 1z and the center line lx of the mass member 2 parallel to the X direction are arranged at point symmetry with respect to the intersection point O, the dynamic damper 1 does not cause directivity in the Z direction and the X direction. Therefore, when the dynamic damper 1 is attached, when the pair of rotation prevention pins 13 are fitted into the depressions 23 provided in advance in the support portion 20, the directionality of the dynamic damper 1 in the Z direction and the X direction is set. Since there is no need to check, the installation work becomes easier.

  On the other hand, in the conventional dynamic damper, the rotation preventing pin is provided at the symmetrical position in the Z direction of the dynamic damper and at the same position in the X direction (see FIG. 7). Because of the prevention pin, left and right directionality occurred in the dynamic damper. As a result, at the time of mounting, when fitting a pair of rotation prevention pins to the depression provided in advance in the support portion, it is necessary to confirm and arrange the left and right directionality of the dynamic damper, The installation work was complicated.

  Further, since the pair of through holes 12 provided in the first bracket 3a and the second bracket 3b are arranged at point-symmetric positions with respect to the intersection point O, similarly to the rotation prevention pin 13, the dynamic damper 1 does not cause the directionality in the Z direction and the X direction. Therefore, when attaching the dynamic damper 1 to the support portion 20, it is not necessary to confirm the directivity of the dynamic damper 1 in the Z direction and the X direction, and the attaching operation becomes easy.

  Since both the first bracket 3a and the second bracket 3b are connected to the mass member 2 via the vibration isolation base 4, vibration is input to the seat back of the vehicle seat, and the mass member 2 and the vibration isolation are connected. When the vibration system constituted by the base 4 resonates, vibration is applied from the vibration-proof base 4 under the influence of the resonance. Here, when the first bracket 3a and the second bracket 3b are separated from each other, the first bracket 3a and the second bracket 3b are only fastened at one place by the fixing bolt 21a and the nut 21b, respectively. . Therefore, as compared with the case where the bracket is integrally formed, it is easily affected by vibration from the vibration isolating base 4 and rattling such as rotation and swinging around the axis of the fixing bolt 21a occurs. easy.

  Therefore, a pair of anti-rotation pins 13 that engage with the pair of depressions 23 are provided on the first bracket 3a and the second bracket 3b, and the movement of the first bracket 3a and the second bracket 3b with respect to the support portion 20 is suppressed. Thus, even when the first bracket 3a and the second bracket 3b are separated from each other, the occurrence of rattling such as rotation or swing during vibration input is suppressed.

  In addition, when the input vibration is particularly large, the mass member may vibrate greatly and interfere with the bracket to generate a hitting sound. However, the first bracket 3a and the second bracket 3b are separated from each other. By placing the first bracket 3a and the second bracket 3b, the hitting sound can be reduced as compared with the case where the first bracket 3a and the second bracket 3b are integrally formed.

  Further, since the pair of rotation prevention pins 13 are disposed on the first bracket 3a and the second bracket 3b so as to be point-symmetric with each other with respect to the intersection point O, the first bracket 3a and the second bracket 3b. Brackets 3b having the same shape can be used, and the types of brackets are reduced by half and are inexpensive and easy to manage.

  The present invention has been described above based on the embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications and changes can be easily made without departing from the spirit of the present invention. Can be inferred.

  For example, in the dynamic damper 1 according to the present embodiment, the bracket side fitting portion is constituted by a protrusion (rotation prevention pin 13), and the support portion side fitting portion is constituted by a depression (depression portion 23). However, on the contrary, the bracket side fitting part may be constituted by a depression, and the support part side fitting part may be constituted by a protrusion.

It is a bottom view of the dynamic damper in one embodiment of the present invention. It is a side view of the dynamic damper shown in FIG. It is a top view of the dynamic damper shown in FIG. (A) is a figure which expands and shows the side part of a mass member, Comprising: It is a figure which shows the state in which a receiving surface inclines at angle (theta) 1 with respect to the Y direction, (b) is a figure which shows the side part of a mass member. It is a figure which expands and is a figure which shows the state which a receiving surface inclines at angle (theta) 2 with respect to the Y direction. It is sectional drawing which shows a cross section perpendicular | vertical to the X direction of the support part of a seat back, and the dynamic damper attached to the support part. It is a figure which shows the state in which the conventional dynamic damper was attached to the seat back of the vehicle seat. It is a figure which shows the conventional dynamic damper, (a) is a bottom view of a dynamic damper, (b) is a side view of a dynamic damper.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Dynamic damper 2 Mass member 3 Bracket 3a 1st bracket 3b 2nd bracket 4 Vibration-proof base 12 Through-hole 13 Anti-rotation pin (bracket side fitting part, protrusion)
20 Support part 21a Fixing bolt (fixing member)
22 mounting hole 23 hollow part (support part side fitting part, hollow)
201 seat back lx center line of mass member parallel to X direction (center line of mass member parallel to second direction)
lz Center line of mass member parallel to Z direction (center line of mass member in first direction)
O Intersection X X direction (second direction)
Z Z direction (first direction)

Claims (8)

A dynamic damper comprising: a mass member as a mass body; a bracket attached to a support portion of a seat back of a vehicle seat; and a vibration isolating base that connects the bracket and the mass member and is formed of a rubber-like elastic body. In
The bracket includes a first bracket connected to one of the mass members in the first direction and a second bracket connected to the other of the mass members in the first direction.
The first bracket and the second bracket have at least a pair of bracket-side fitting portions that are fitted to at least a pair of support-side fitting portions provided in the support portion,
The at least one pair of bracket-side fitting portions are pointed to each other with reference to an intersection of a center line of the mass member parallel to the first direction and a center line of the mass member parallel to the second direction perpendicular to the first direction. A dynamic damper characterized by being arranged in a symmetrical position.   The said bracket side fitting part is comprised by protrusion, and the support part side fitting part provided in the said support part is comprised by the hollow fitted with the said bracket side fitting part. Dynamic damper. The first bracket and the second bracket have at least a pair of through holes through which a fixing member for attaching and fixing the first bracket and the second bracket to the support portion is inserted,
3. The dynamic damper according to claim 1, wherein at least a pair of through-holes provided in the first bracket and the second bracket are disposed at point-symmetric positions with respect to the intersection point. 4.   The dynamic damper according to any one of claims 1 to 3, wherein the first bracket and the second bracket are separated from each other. A dynamic damper comprising: a mass member as a mass body; a bracket attached to a support portion of a seat back of a vehicle seat; and a vibration isolating base that connects the bracket and the mass member and is formed of a rubber-like elastic body. In the mounting structure of the dynamic damper for mounting to the support portion of the seat back,
The bracket includes a first bracket connected to one of the mass members in the first direction and a second bracket connected to the other of the mass members in the first direction.
At least a pair of bracket-side fitting portions provided on the first bracket and the second bracket;
A support portion-side fitting portion that is provided on the support portion and fits with the at least one pair of bracket-side fitting portions;
The at least one pair of bracket-side fitting portions are pointed to each other with reference to an intersection of a center line of the mass member parallel to the first direction and a center line of the mass member parallel to the second direction perpendicular to the first direction. A dynamic damper mounting structure, characterized in that it is arranged in a symmetrical position.   The said bracket side fitting part is comprised by protrusion, and the support part side fitting part provided in the said support part is comprised by the hollow fitted with the said bracket side fitting part. Dynamic damper mounting structure. At least a pair of through holes provided in the first bracket and the second bracket, and through which a fixing member for fixing the first bracket and the second bracket to the support portion is inserted;
Provided in the support portion, and including at least a pair of mounting holes that are inserted through the through holes and through which the fixing member is inserted;
The dynamic damper mounting structure according to claim 5 or 6, wherein the at least one pair of through holes are arranged at point-symmetric positions with respect to the intersection.   The dynamic damper mounting structure according to any one of claims 5 to 7, wherein the first bracket and the second bracket are separated from each other.

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