JP2006194266A - Dynamic damper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dynamic damper suppressing undesirable motion such as swing motion of a mass member, properly damping vibration input in an axial direction and a direction perpendicular to the axial direction, increasing durability of a rubber elastic body, preventing interference with surrounding mating member, and reducing occupancy space. <P>SOLUTION: The dynamic damper 10 is attached to a vibration control subject member by a U-shape attachment metal fitting 31 fixed on an inner cylinder metal fitting 12 by having a pair of rubber bushing provided with an inner cylinder metal fitting 12 and an outer cylinder metal fitting 14 separately arranged outward in a radial direction, and a rubber elastic body 17 connecting the inner and the outer cylinder metal fitting 12, 14, pressed and fitted in a through hole 27 of a cylindrical mass member 25 from an axial direction both ends, and fastened in an axial direction by a nut 41 and a bolt 39 inserted through a shaft hole of the inner cylinder metal fitting 12. The mass member 25 is supported by an inner cylinder metal fitting 12 at two sections on both end sides in an axial direction via the rubber elastic body 17. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention provides a dynamic damper in which an inner cylindrical metal fitting and a cylindrical mass member disposed radially outward thereof are connected via a rubber elastic body to attenuate vibration input in the axial direction and the direction perpendicular to the axial direction. About.

Conventionally, as this type of dynamic damper, for example, as shown in Patent Document 1, an inner cylindrical metal fitting and a cylindrical mass member disposed radially outward thereof are connected by a rubber elastic body, and are axially Is fixed to a vehicle suspension member or the like so that the vibration input from the vehicle in the vertical direction (axial direction) and the front-rear direction (axial perpendicular direction) is attenuated (see FIG. 1). 4). However, since this dynamic damper has a high degree of freedom of vibration of the mass member, an undesirable vibration such as a swing is likely to occur particularly with respect to a vibration input of a low frequency around 20 Hz. Therefore, the original performance of attenuating the vibrations in the vertical and longitudinal directions of the vehicle is impaired, and the durability is impaired due to the concentration of local stress on the rubber elastic body. In addition, the mass member may swing, causing the mass member to hit other members disposed around the dynamic damper and damage them. In order to avoid this, it is necessary to make a large installation space for the dynamic damper, but there is a possibility that it cannot be used in a limited space such as in the engine room of the vehicle.
Japanese Utility Model Publication No. 6-80043

  On the other hand, as shown in Patent Document 1, a mass body having a plurality of through-holes having parallel axes, and a plurality of parallel cores each having one end fixed to the vibrating body and positioned at the center of each through-hole, respectively. There is known a dynamic damper comprising a member and a rubber elastic body integrally connecting an inner peripheral surface of the through hole and an outer peripheral surface of a core member located at the center of the through hole (FIGS. 3). In the case of this dynamic damper, since the mass body is supported by a plurality of core members, the degree of freedom of vibration of the mass body is greatly restricted, and vibration in the intended direction can be attenuated. . However, even in this dynamic damper, since each core member supports the mass body at one axial position, it is not possible to sufficiently prevent undesirable operations such as swinging of the mass body. The above problem has not been sufficiently solved.

  The present invention is intended to solve such problems, and suppresses undesired operations such as swinging of the mass member, appropriately attenuates the vibration input in the axial direction and the direction perpendicular to the axis, and durability of the rubber elastic body. An object of the present invention is to provide a dynamic damper capable of reducing the occupation space and reducing the occupation space.

  In order to achieve the above object, the structural features of the present invention include an inner cylinder fitting, an outer cylinder fitting spaced apart radially outward of the inner cylinder fitting, and a rubber connecting the inner and outer cylinder fittings. A pair of rubber bushes each provided with an elastic body are inserted into the through-holes of the cylindrical mass member by press-fitting from both ends in the axial direction of the mass member, and the pair of rubber elastic bodies are respectively positioned on both ends in the axial direction of the mass member The mounting bracket is fixed to the axial outer ends of the pair of inner cylinder fittings that protrude outward from the through holes, and the axial inner ends of the pair of inner cylinder fittings are in contact with each other in the through holes. It is to be attached to the vibration suppression target member by the mounting bracket.

  In the present invention configured as described above, a pair of rubber bushes are inserted into the through holes of the cylindrical mass member by press-fitting from both ends in the axial direction of the mass member, It is connected to the inner tube metal fitting by a rubber elastic body at a location. Thereby, since the mass member is supported by the inner cylindrical metal fitting via the rubber elastic body at two locations on both ends in the axial direction, an undesirable operation such as swinging of the mass member is effectively suppressed. Therefore, the dynamic damper can properly exhibit the function of attenuating vibration input in the original axial direction and the direction perpendicular to the axis. Further, since the undesirable swinging motion of the mass member is suppressed, the concentration of local stress on the rubber elastic body is suppressed, so that the durability of the rubber elastic body is ensured. Furthermore, by suppressing the swinging of the mass member, interference between the mass member and the counterpart member disposed around the mass member can be avoided, and damage to the counterpart member can be prevented. In addition, since the swinging of the mass member is suppressed, the space occupied by the dynamic damper can be reduced, and the degree of freedom of installation in the narrow space of the dynamic damper is increased.

  Further, in the present invention, the mounting bracket is formed in a U shape by a pair of side plate portions facing each other and a connecting plate portion connecting the pair of side plate portions, and the pair of inner cylinders at the pair of side plate portions. They may be fixed to the outer ends in the axial direction of the metal fittings and sandwich a pair of inner cylindrical metal fittings. Thus, the space occupied by the dynamic damper can be reduced by the simple mounting structure in which the mounting bracket is U-shaped and fixed to the outer end of the inner cylinder bracket in the axial direction. In addition, since the pair of side plate portions fixed to the outer end in the axial direction of the inner cylinder fitting also functions as a stopper against excessive vibration in the axial direction of the mass member, it is not necessary to prepare a stopper as a separate member. In other words, the mounting bracket has a function as a stopper in addition to the function of attaching to the original mating member, and the value as a member is increased.

  Further, in the present invention, the inner ends in the axial direction of the pair of outer cylinder fittings are separated from each other in the axial direction, and the axial inner ends of the pair of outer cylinder fittings are located in the middle of the inner circumferential surface of the mass member. An annular projecting portion projecting inward in the radial direction may be provided, and an inner buffer rubber portion may be provided on each of the outer peripheral surfaces of the pair of inner cylinder fittings facing the projecting portion. Thereby, the annular projecting portion projecting inward in the radial direction of the mass member is configured as a simple radial stopper that abuts on the inner shock absorbing rubber portion provided on the outer peripheral surface of the inner cylindrical metal fitting, and by a large radial vibration input The relative displacement in the radial direction of the mass member can be suppressed within an appropriate range without causing noise.

  Moreover, in this invention, the annular flange part extended in the radial direction outward is provided in the axial direction outer end of a pair of outer cylinder metal fittings, respectively, and an outer shock absorbing rubber is provided in the opposing surface with the attachment metal fitting of a pair of flange parts, respectively. A portion may be provided. As a result, the flange portion provided at the outer end in the axial direction of the outer cylinder fitting of the pair of rubber bushes is configured as an axial stopper that abuts against the opposing surface of the mounting bracket via the outer shock-absorbing rubber portion. The relative displacement in the axial direction of the mass member due to input can be suppressed within an appropriate range without causing noise.

  In the present invention, the pair of rubber elastic bodies are provided with a pair of straight portions penetrating in the axial direction on both sides in the radial direction across the pair of inner cylindrical fittings corresponding to the vibration input in the direction perpendicular to the axis. May be. Thereby, since the spring constant of the rubber elastic body is adjusted according to the frequency of vibration input in the direction perpendicular to the axis by the pair of straight portions, the vibration input can be appropriately attenuated according to the frequency.

  Further, in the present invention, the mounting bracket has a pair of ticklings in a state where the pair of side plate portions are directed in the vertical direction and attached to the vibration damping target member of the vehicle at the connecting plate portion with respect to the left-right direction of the vehicle. The portion may be arranged in the front-rear direction of the vehicle. Thus, even if the mounting angle of the connecting plate portion of the mounting bracket to the vehicle damping target member is different, the pair of straight portions of the rubber elastic body can be arranged in the front-rear direction of the vehicle. Since the spring constant of the rubber elastic body can be adjusted by the straight portion according to the input frequency, the vibration input in the longitudinal direction of the vehicle can be appropriately damped according to the frequency.

  According to the present invention, a pair of rubber bushings are fitted into the through-holes of the cylindrical mass member by press-fitting from both ends in the axial direction of the mass member, so that the mass member is elastic at two locations on both axial sides. Since it is supported by the inner cylinder fitting through the body, undesirable operations such as swinging and twisting of the mass member are effectively suppressed. As a result, in the present invention, the dynamic damper can properly exhibit the function of attenuating vibration input in the original axial direction and the direction perpendicular to the axis, and the durability of the rubber elastic body can be improved. Further, in the present invention, the swinging of the mass member can be suppressed, so that the counterpart member arranged around the dynamic damper can be prevented from being damaged, and the space occupied by the dynamic damper can be reduced to reduce the installation space in the narrow space. The degree of freedom is increased.

  In addition, in the present invention, the mounting space of the dynamic damper can be reduced and the pair of side plates can be suppressed by adopting a simple mounting structure in which the mounting bracket is U-shaped and fixed to the axially outer end of the inner cylindrical bracket. Since the portion functions also as a stopper against excessive relative displacement in the axial direction of the mass member, it is not necessary to prepare a stopper as a separate member. Further, in the present invention, the annular projecting portion projecting inward in the radial direction of the mass member is configured as a simple radial stopper that comes into contact with the inner shock absorbing rubber portion provided on the outer peripheral surface of the inner cylinder bracket. Relative displacement due to large radial vibration input can be suppressed within an appropriate range without causing noise. Furthermore, in the present invention, the flange portion provided at the outer end in the axial direction of the outer cylinder fitting of the pair of rubber bushes is configured as an axial stopper that abuts against the opposing surface of the mounting bracket via the outer shock-absorbing rubber portion. As a result, relative displacement due to large vibration input in the axial direction can be suppressed within an appropriate range without causing noise. Further, in the present invention, since the spring constant of the rubber elastic body can be adjusted according to the frequency of vibration input in the direction perpendicular to the axis by the pair of straight portions, the vibration input can be appropriately attenuated according to the frequency. Furthermore, in the present invention, even if the mounting angle of the connecting plate portion of the mounting bracket to the vehicle vibration target member is different, the pair of straight portions of the rubber elastic body can be arranged in the front-rear direction of the vehicle. Since the spring constant of the rubber elastic body can be adjusted according to the frequency of the vibration input, the vibration input in the longitudinal direction of the vehicle can be appropriately damped.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1, 2, 3, and 4 are a front sectional view, a side sectional view, a front view, and a dynamic damper that is attached to a vehicle body side member of a vehicle according to an embodiment in a state where the axial direction is directed upward and downward of the vehicle. This is shown by a plan view. 5, FIG. 6 and FIG. 7 show the rubber bush constituting the dynamic damper by a plan view, a VI-VI sectional view and a VII-VII sectional view.

  The dynamic damper 10 has the same shape including an inner cylinder fitting 12, an outer cylinder fitting 14 that is spaced apart radially outwardly, and a rubber elastic body 17 that connects the inner and outer cylinder fittings 12 and 14, respectively. A pair of rubber bushes 11, a cylindrical mass member 25 in which the pair of rubber bushes 11 are press-fitted into the through-holes 27 from both ends in the axial direction, and the inner ends of the inner cylindrical fittings 12 at the inner ends in the axial direction. A substantially U-shaped mounting bracket 31 that is fastened in the axial direction by fastening bolts and nuts 39 and 41 inserted through the shaft hole 13 of the tubular fitting 12 and fixed to the inner tubular fitting 12 is configured. 1 to 4, the X direction indicates the front direction of the vehicle, the Y direction indicates the left and right direction of the vehicle, and the Z direction indicates the upward direction.

The rubber bush 11 will be described in detail with reference to FIGS.
The inner cylinder fitting 12 is a cylindrical thick straight pipe. The outer cylinder fitting 14 is a pipe having a thin cylindrical shape and a straight axial length that is approximately half of that of the inner cylinder fitting, and an annular shape in which one axial end (the upper end in FIG. 6) is bent radially outward. The flange portion 15 is provided. The outer cylinder fitting 14 is disposed on one end side in the axial direction of the inner cylinder fitting 12 (the upper end side in FIG. 6), and the flange portion 15 is slightly separated from the one end of the inner cylinder fitting 12 in the axial direction. Is slightly protruding upward in the axial direction.

  The rubber elastic body 17 connects the inner and outer cylinder fittings 12, 14, and has a pair of recesses 18 in which both ends in the axial direction are indented by about 1/3 in the axial direction along the entire circumference in the axial direction. Have. Further, the rubber elastic body 17 is an outer shock-absorbing rubber portion 19 that covers the vertical surface of the flange portion 15 on one end side in the axial direction, and the inner cylindrical fitting 12 that protrudes from the outer cylindrical fitting 14 on the opposite side in the axial direction. The inner buffer rubber portion 21 is coated on the outer peripheral surface of the inner shock absorber. Further, the rubber elastic body 17 is provided with a pair of straight portions 22 which are through holes extending on both sides in the axial direction so as to face both sides in the radial direction across the inner cylinder fitting 12. The straight portion 22 has a substantially U-shaped cross-sectional shape perpendicular to the axis extending from the outer periphery of the inner shock absorbing rubber portion 21 toward the inner peripheral surface of the outer cylinder fitting 14. A rubber protrusion 23 is provided on the inner peripheral surface side of the outer tube metal 14 with respect to the straight portion 22. By adjusting the shape and arrangement of the straight portion 22, the resonance characteristics of the dynamic damper 10 matched to the frequency of the vibration input can be obtained. The rubber elastic body 17 is integrally formed by rubber vulcanization molding with the inner cylinder fitting 12 and the outer cylinder fitting 14 set in a mold, whereby the rubber bush 11 is obtained.

  As shown in FIGS. 3 and 4, the mass member 25 has a substantially rectangular parallelepiped block shape having a predetermined thickness and having a pair of substantially square opposed planes, and has a cylindrical shape vertically penetrating between both planes at the center of the plane. This is a cylindrical metal fitting having a through hole 27. In the plane of the mass member 25, a single alignment groove 25a, which is a thin groove inclined approximately 20 ° from the vertical to one side of the square from the center of the through hole 27, is formed. The inner peripheral surface of the through-hole 27 of the mass member 25 is an annular projecting portion 26 in which the axial length in the axial direction is approximately 1/3 of the entire length and protrudes in the axial direction from the inner peripheral surface. Therefore, the through-hole 27 is a small-diameter hole 28 in the protruding portion 26, and both axial sides other than the protruding portion 26 are large-diameter holes 29. The inner diameter of the large-diameter hole 29 is slightly smaller than the outer diameter of the outer cylinder fitting 14. The inner diameter of the small-diameter hole 28 is approximately halfway between the outer diameter of the outer cylinder fitting 14 and the outer diameter of the inner cylinder fitting 12. The inner peripheral surfaces of the small diameter hole 28 and the large diameter hole 29 are both flat surfaces parallel to the axial direction.

  The pair of rubber bushes 11 are inserted into the through-holes 27 of the mass member 25 by press-fitting, with the flange portion 15 of the outer cylinder fitting 14 being outside. The outer cylinder fitting 14 is press-fitted into the large-diameter hole 29 until the flange portion 15 comes into contact with both ends of the mass member 25 in the axial direction, whereby the inner ends of both the inner cylinder fittings 12 are brought into contact with each other. The metal fitting 14 is tightly fixed to the large diameter hole 29. Here, in the press-fitting of the rubber bush 11, as shown in FIG. 4, the straight portion 22 of the rubber elastic body 17 is aligned with the opposing square side of the mass member 25 in accordance with the alignment groove 25 a of the mass member 25. Slightly inclined from the vertical. Further, the gap between the protruding portion 26 of the mass member 25 and the inner shock absorbing rubber portion 21 covering the outer peripheral surface of the inner cylindrical metal member 12 is a gap between the outer peripheral surface of the mass member 25 and the intermediate plate portion 33 of the mounting metal member 31 described later. Have been smaller. Thereby, the radial stopper mechanism is constituted by the protruding portion 26 and the inner cylindrical metal member 12 via the inner buffer rubber portion 21. In addition, although the outer cylinder metal fitting 14 functions also as a part of mass member in the state pressed and united with the mass member 25, in the following description, the mass member 25 including the outer cylinder metal fitting 14 is included. Will be described.

  The mounting bracket 31 is made of a metal plate and has a substantially rectangular connecting plate portion 32. The connecting plate portion 32 has a rectangular intermediate plate portion 33 in the longitudinal direction, and a pair of both sides in the longitudinal direction. A mounting plate portion 34 is provided. The longitudinal length of the intermediate plate portion 33 is approximately 3/5 of the entire mounting bracket, and the longitudinal length of the mounting plate portion 34 is approximately 1/5. The boundary between the intermediate plate portion 33 and the mounting plate portion 34 is a step 33a, and the intermediate plate portion 33 is parallel to the mounting plate portions 34 on both sides and slightly lifted across the step 33a. The mounting plate portion 34 has both sides 34a in the width direction bulging outwards in a circular arc shape, and bolts 35 are respectively inserted into the mounting holes (not shown) provided in the center of the circular arc shape from the side plate portion 36 side described later. The head 35a is fixed to the mounting plate 34 by welding or the like. On both side edges in the width direction of the intermediate plate portion 33, a pair of side plate portions 36 are integrally provided by being bent perpendicularly to the intermediate plate portion 33 and in a direction opposite to the mounting plate portion 34.

  The side plate portion 36 has a substantially rectangular shape and a semicircular shape with the tip side aligned with the outer periphery of the flange portion 15 of the outer cylindrical metal member 14. The height from the intermediate plate portion 33 to the center of the semicircular shape is a square of the mass member 25. It is larger than half of the side length. The distance between the opposing surfaces between the pair of side plate portions 36 is equal to the axial length of the pair of inner cylinder fittings 12 combined. Further, at the boundary between the intermediate plate portion 33 and the pair of side plate portions 36, the intermediate portion in the width direction is recessed inwardly to form a reinforcing portion 37 inclined at approximately 45 °. The mounting bracket 31 is formed by pressing and bending a rectangular metal plate. Furthermore, a fixing hole 38 is provided on each of the tip end sides of the pair of side plate portions 36 and in the center in the width direction. The fixing hole 38 is disposed coaxially with the semicircular shape on the tip side of the side plate portion 36, and the inner diameter thereof is substantially the same as the inner diameter of the shaft hole 13 of the inner cylinder fitting 12.

  The mass member 25 to which the rubber bush 11 is fixed is further interposed between the pair of side plate portions 36 of the mounting bracket 31 so that the sides of the mass member 25 are parallel to the intermediate plate portion 33. It arrange | positions in the state which match | combined the axial hole 13 of the inner cylinder metal fitting 12 with the fixing hole 38. FIG. With this arrangement, the tightening bolt 39 is inserted into the pair of fixing holes 38 and the shaft hole 13 of the inner cylindrical metal member 12, and the nut 41 is screwed onto the projecting end of the tightening bolt 39 with the washer 42 interposed therebetween. Thus, the mounting bracket 31 is fixed to both ends of the inner cylinder bracket 12, and the dynamic damper 10 is obtained. In the dynamic damper 10, the pair of side plate portions 36 of the mounting bracket 31 facing each other and the flange portion 15 of the outer cylindrical bracket 14 covered with the outer cushioning rubber portion 19 facing this are excessively increased in the axial direction (vertical direction). An axial stopper is configured to suppress the relative displacement of the mass member 25 in the axial direction with respect to various vibration inputs.

  As shown in FIG. 8, the dynamic damper 10 includes the connecting plate portion 32 in a state where the pair of side plate portions 36 are turned up and down, the axial direction is directed in the up and down direction, and the pair of straight portions 22 are directed in the vehicle front-rear direction. Is superimposed on the suspension member S, which is a vibration suppression target member provided on both the left and right sides of the vehicle, and nuts (not shown) are screwed onto the tips of the four bolts 35 erected on the connecting plate portion 32. It is fixed to the suspension member S. Here, the suspension member S is slightly inclined with respect to the left-right direction of the vehicle (the Y direction in the figure), but the pair of straight portions 22 of the rubber elastic body 17 are previously inclined with respect to the connecting plate portion 32. Therefore, the straight portion 22 is arranged facing the front and rear of the vehicle.

  In the embodiment of the above configuration, the dynamic damper 10 includes the pair of rubber bushes 11 that are inserted into the through holes 27 of the cylindrical mass member 25 by press-fitting from both ends in the axial direction. It is connected to the inner cylinder fitting 12 by a pair of rubber elastic bodies 17 at two places on both ends in the direction. As described above, since the mass member 25 is supported by the inner cylindrical metal member 12 via the rubber elastic body 17 at two positions in the axial direction, an undesirable operation such as a swinging motion or twisting of the mass member 25 is effective. To be suppressed. Therefore, the dynamic damper 10 can properly exhibit the function of attenuating vibration input in the original vehicle vertical direction (axial direction) and vehicle longitudinal direction (axial perpendicular direction). Moreover, since the undesired operation of the mass member 25 is suppressed, concentration of local stress on the rubber elastic body 17 is suppressed, so that the durability of the rubber elastic body 17 is ensured. Further, by suppressing the swing of the mass member 25, it is possible to avoid a collision with a surrounding partner member in the vehicle, and to prevent the partner member from being damaged. Further, since the swing of the mass member 25 is suppressed, the space occupied by the dynamic damper 10 can be reduced, and the degree of freedom in installing the dynamic damper 10 in a narrow space of the vehicle is increased.

  In the present embodiment, the mounting bracket 31 has a simple U-shape and sandwiches both outer ends of the inner cylindrical bracket 12 so that the space occupied by the dynamic damper 10 can be suppressed. Moreover, the axial direction stopper which suppresses the amplitude with respect to an excessive axial direction (vertical direction) vibration input is comprised by the flange part 15 of the outer cylinder metal fitting 14 coat | covered with the side plate part 36 and the external shock absorbing rubber part 19 which mutually oppose. Yes. Therefore, it is not necessary to prepare a separate axial stopper. In other words, the mounting bracket 31 has a function as a stopper in addition to the function of mounting to the original mating member, and the value as a member is increased. Further, the annular projecting portion 26 projecting inward in the radial direction of the mass member 25 functions as a radial stopper by coming into contact with the inner shock absorbing rubber portion 21 provided on the outer peripheral surface of the inner cylinder fitting 12. Therefore, it is not necessary to prepare a separate radial stopper.

  In the present embodiment, the suspension member S is slightly inclined with respect to the left-right direction of the vehicle. However, the pair of treads of the rubber elastic body 17 is attached to the suspension member S where the connecting plate portion 32 is inclined. The part 22 is arranged facing the front-rear direction of the vehicle. Therefore, the spring constant of the rubber elastic body 17 can be adjusted according to the frequency of vibration input in the vehicle front-rear direction by the tick portion 22, so that the vibration input in the front-rear direction of the vehicle can be appropriately attenuated according to the frequency. The arrangement of the pair of straight portions 22 and the connecting plate portion 32 is arbitrarily adjusted by changing the angle of the straight portion 32 with respect to the connecting plate portion 32 when the rubber bush 11 is press-fitted into the mass member 25. can do. Therefore, according to the inclination of the suspension member of the vehicle to which the connecting plate portion 32 is attached, the pair of straight portions 22 can be arranged in the front-rear direction of the vehicle. Therefore, regardless of the inclination state of the suspension member S, the vibration input in the front-rear direction of the vehicle can be appropriately attenuated according to the frequency.

  It should be noted that the dynamic damper shown in the above embodiment can be applied to a vibration suppression target member other than the vehicle. Moreover, the structure of each part of the rubber bush, the mass member, and the mounting bracket of the dynamic damper shown in the above embodiment is an example, and various modifications can be made without departing from the gist of the present invention.

  In the present invention, the mass member is connected to the inner cylindrical metal fitting through the rubber elastic body at two locations in the axial direction, and is supported by the rubber elastic body at two locations on both ends in the axial direction. Undesirable movement such as swinging is effectively suppressed, and as a result, the function of damping the vibration input in the axial direction and the axis perpendicular direction of the dynamic damper can be properly exerted, and the durability of the rubber elastic body is improved and the surroundings This is useful because it is possible to prevent damage to the mating member disposed in the space, further reduce the occupied space, and increase the degree of freedom of installation in a narrow space.

It is front sectional drawing of the II line direction of FIG. 4 which shows the dynamic damper which is an Example of this invention. It is side surface sectional drawing of the II-II line direction of FIG. 4 which shows the same dynamic damper. It is a front view which shows the dynamic damper. It is a top view which shows the dynamic damper. It is a top view which shows the rubber bush which comprises the same dynamic damper. It is sectional drawing of the VI-VI line direction of FIG. 5 which shows the rubber bush. It is sectional drawing of the VII-VII line direction of FIG. 5 which shows the rubber bush. It is a top view which shows the attachment state to the other party member of the dynamic damper.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Dynamic damper, 11 ... Rubber bush, 12 ... Inner cylinder metal fitting, 14 ... Outer cylinder metal fitting, 15 ... Flange part, 17 ... Rubber elastic body, 19 ... Outer buffer rubber part, 21 ... Inner buffer rubber part, 22 ... Immediately , 25 ... mass member, 26 ... projection, 27 ... through hole, 28 ... small diameter hole, 29 ... large diameter hole, 31 ... mounting bracket, 32 ... coupling plate portion, 33 ... intermediate plate portion, 34 ... mounting plate portion , 36 ... side plate portions, 38 ... fixing holes, 39 ... fastening bolts.

Claims (6)

A pair of rubber bushings each provided with an inner cylinder fitting, an outer cylinder fitting spaced apart radially outward of the inner cylinder fitting, and a rubber elastic body connecting the inner cylinder fitting and the outer cylinder fitting Are inserted into the through holes of the cylindrical mass member by press-fitting from both ends in the axial direction of the mass member, and the pair of rubber elastic bodies are respectively disposed on both ends in the axial direction of the mass member. A mounting bracket is fixed to the axially outer ends of the pair of inner cylinder brackets protruding outward, and the axial inner ends of the pair of inner cylinder brackets are in contact with each other in the through hole, and the mounting bracket The dynamic damper is attached to a vibration-damping target member. The mounting bracket is formed in a U shape by a pair of side plate portions facing each other and a connecting plate portion for connecting the pair of side plate portions, and the pair of side plate portions of the pair of inner cylinder brackets 2. The dynamic damper according to claim 1, wherein the pair of inner cylinder fittings are fixed to the outer ends in the axial direction to sandwich the pair of inner cylinder fittings. The axial inner ends of the pair of outer cylinder fittings are axially separated from each other, and the axial inner ends of the pair of outer cylinder fittings are radially inward in the middle of the inner circumferential surface of the mass member. An annular cushioning portion projecting in the direction is provided, and an internal shock absorbing rubber portion is provided on each of the outer peripheral surfaces of the pair of inner cylinder fittings facing the projecting portion. Dynamic damper. An annular flange portion extending radially outward is provided at each axially outer end of the pair of outer tube fittings, and an outer shock absorbing rubber portion is provided on a surface of the pair of flange portions facing the mounting bracket. The dynamic damper according to claim 1, wherein the dynamic damper is provided. In the pair of rubber elastic bodies, a pair of straight portions penetrating in the axial direction are provided on both sides in the radial direction across the pair of inner cylinder fittings corresponding to vibration input in a direction perpendicular to the axis. Item 5. The dynamic damper according to any one of Items 1 to 4. In the state where the mounting bracket is directed to the pair of side plate portions in the vertical direction and attached to the vibration-damping target member of the vehicle at the connecting plate portion with respect to the left-right direction of the vehicle. The dynamic damper according to claim 5, wherein the portion is disposed toward the front-rear direction of the vehicle.

Images