JPH11101306A - Dynamic damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dynamic damper in which the press in and installation work to a rotary shaft is easy and the wear resistance of a fixing metal fitting can be ensured and the free length of a connection support part is ensured and the strength of the connection support part and the characteristic design of the dynamic damper are advantageous. SOLUTION: This damper is provided with a rubber made cylindrical member 1 having a connection support, part 5 integrally formed to the boss part 4 in which a rotary shaft is pressed in and the outer surface of the boss part 4, a ring shape mass member 2 arranged in the radius direction outside of the boss part 4 and connected and supported elastically for the boss part, 4 by a connection support part 5 and a ring shape fixing metal fitting 3 for fixing the boss part 4 to the rotary shaft. The fixing metal fitting 3 is arranged to the axial direction one end side of the base part 4 so as not to overlap the connection support part 5 to the radius direction and also built in the boss part 4 substantially so that at least inner/outer periphery surfaces are covered by a rubber. A positioning recessed part 4b for positioning the fixing metal fitting 3 in the axial direction at the vulcanizing and molding time is formed in the boss part, 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dynamic damper which is mounted on a rotating shaft such as a drive shaft of an automobile and suppresses harmful vibration generated on the rotating shaft.

[0002]

2. Description of the Related Art In order to suppress harmful vibrations that should not normally occur, such as bending vibrations and torsional vibrations due to rotational imbalance caused by the rotation of rotating shafts such as drive shafts and propeller shafts of automobiles, Dynamic dampers are often used. These dynamic dampers perform their functions by matching the natural frequency to the dominant frequency of the harmful vibration to be excited, thereby converting and absorbing the vibration energy of the rotating shaft as the vibration energy of the dynamic damper by resonance. I have.

[0003] As such a dynamic damper, those shown in FIG. 14 and those shown in FIG. 15 are conventionally known. The dynamic damper shown in FIG. 14 (hereinafter, referred to as “A-type dynamic damper”) is formed integrally with a boss 71 having a center hole 71 a fitted or press-fitted on a rotating shaft, and an outer surface of the boss 71. Connection support part 7
A ring-shaped mass member 80 disposed radially outside the boss portion 71 and elastically connected and supported by the connection support portion 72 to the boss portion 71; The boss 7 is fitted over the outer peripheral surface of the boss 71.
Stainless steel band 90 for fixing 1 to the rotating shaft
It is composed of

A dynamic damper shown in FIG. 15 (hereinafter referred to as "B type dynamic damper").
Is a boss 7 having a center hole 71a into which a rotating shaft is press-fitted.
1 and a rubber cylindrical member 70 comprising a connection support portion 72 integrally formed on the outer surface of the boss portion 71, and a rubber support member disposed radially outside the boss portion 71, and the connection support portion with respect to the boss portion 71. A ring-shaped mass member 80 elastically connected and supported by 72, and a ring-shaped fixture 90 'substantially embedded in the boss portion 71 for fixing the boss portion 71 to the rotating shaft. Have been.

[0005] In these dynamic dampers, the connection support portion 72 elastically supporting the mass member 80 receives a load in the compression and tension directions with respect to the vibration of the mass member 80 in the radial direction. That is, the connection support portion 72
Is the mass member 80 in the direction having the compression / tension spring constant.
Is elastically supported. For this reason, the natural frequencies of these dynamic dampers are basically determined by the mass of the mass member 80 and the compression / tension spring constant of the connection support portion 72. For example, the natural frequency of the dynamic damper can be set low by reducing the compression / tension spring constant of the connection support portion 72 or increasing the mass of the mass member 80. Here, the compression / tensile spring constant of the connection support 72 is determined by the shape of the connection support 72 and the mass member 8.
The length can be reduced by increasing the vibration direction in the zero direction, that is, in the radial direction of the cylindrical member 70.

[0006]

However, the aforementioned A
In the dynamic damper of the type, the center hole 71a of the boss portion 71 is fitted on the rotating shaft when the boss portion 71 is attached to the rotating shaft, and then a stainless steel band 90 as a separate member is mounted on the boss portion 7.
Since it is necessary to mount and fasten to the outer peripheral surface of No. 1, there are disadvantages that the number of steps is large and the mounting work is troublesome.

Further, since the outer peripheral surface of the stainless steel band 90 is exposed, it is necessary to use a material having a high rustproofing property or to perform a surface treatment on the stainless steel band 90 in order to secure the corrosion resistance. There is also a disadvantage that the cost rises. On the other hand, the B-type dynamic damper has the above-mentioned drawbacks of the A-type dynamic damper because the fixing bracket 90 'for fixing the boss 71 to the rotating shaft is substantially built in the boss 71. Although not shown, the fixture 90 'and the connection support portion 72 have a structure in which they are laminated in the radial direction of the boss portion 71, and the laminated structure has the following various disadvantages.

First, it is necessary to avoid an increase in the diameter of the dynamic damper due to restrictions on the mounting space and the like. However, in the case of the above-mentioned laminated structure, it is necessary to increase the free length of the connecting support portion 72 in the radial direction of the fixing bracket 90 '. Because the thickness is limited by the thickness, it is difficult to set the natural frequency of the dynamic damper low by increasing the free length of the connecting support portion 72 while avoiding an increase in the diameter of the dynamic damper. Above, disadvantageous.

If the free length of the connecting support 72 cannot be increased, the mass member 80 vibrates largely in the radial direction and a large external force acts on the connecting support 72.
It becomes difficult to secure the strength of the connection support portion 72. Further, the boss 71 is attached to the rotation shaft by the center hole 71.
This is performed by press-fitting the rotating shaft into the a. However, in the above-described laminated structure, if the free length of the connection support portion 72 is to be increased while avoiding an increase in the diameter of the dynamic damper, the position of the connection support portion 72 in the radial direction is reduced. As a result, the rubber portion of the boss portion 71 which can be elastically deformed at the time of press fitting is inevitably thinned in the radial direction. For this reason, at the time of press-fitting, a large force is required to greatly deform the thin rubber portion, and the press-fitting property to the rotating shaft is reduced. That is, the original thickness T ₀ before press-fitting is thinner,
When the thickness after press-fitting is T, R = (T ₀ −T) / T ₀
As a result, at the time of press-fitting, it is necessary to apply a large force so that the rubber portion is greatly distorted, and the press-fitting property to the rotating shaft is reduced.
Moreover, in the B-type dynamic damper, the fixing fitting 90 'built in the boss 71 extends over the entire length of the boss 71 in the axial direction. Since the boss portion 71 is constrained by the fixture 90 'over the entire length in the axial direction, it becomes more difficult to press the boss portion 71 into the rotary shaft.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks of the conventional A-type and B-type dynamic dampers, and it is easy to press-fit and attach to a rotating shaft, and to secure the corrosion resistance of a fixing bracket. Another object of the present invention is to provide a dynamic damper which is advantageous in terms of strength of the connecting support portion and characteristic design of the dynamic damper by securing a free length of the connecting support portion.

[0011]

[Means for Solving the Problems]

(1) The dynamic damper according to the first aspect is a rubber cylinder having a cylindrical boss having a center hole into which a rotating shaft is press-fitted, and a connection support formed integrally with an outer surface of the boss. A member, a ring-shaped mass member disposed radially outside of the boss portion and elastically connected and supported by the connection support portion to the boss portion, and for fixing the boss portion to the rotating shaft. A ring-shaped fixture is provided, and the fixture is disposed at one axial end of the boss portion so as not to overlap with the connection support portion in the radial direction, and at least an inner peripheral surface and an outer peripheral surface are provided. The boss is substantially embedded in the boss so as to be covered with the rubber constituting the boss, and the boss is provided at least in the axial direction at the other end in the axial direction of the boss among the axial end surfaces of the fixing bracket. End face abuts on positioning jig Is formed by vulcanization molding in a state where the fixing bracket is positioned in the vulcanization mold in the axial direction, and the boss portion has a positioning recess extending from the outside to the axial end face of the fixing bracket, It is formed at the position where the positioning jig was located at the time of vulcanization molding. (2) The dynamic damper according to the second aspect is the first aspect.
In the dynamic damper described in the above, a plurality of the connection support portions are formed at equal intervals in a circumferential direction, and at least two positioning recesses are formed at a circumferential interval, and each of the positioning recesses is adjacent to each other. It is characterized by being arranged so as to correspond to the space between the mating connection supporting portions and the circumferential direction.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION

(1) The dynamic damper according to the first aspect is a rubber cylinder having a cylindrical boss having a center hole into which a rotating shaft is press-fitted, and a connection support formed integrally with an outer surface of the boss. A member, a ring-shaped mass member disposed radially outside of the boss portion and elastically connected and supported by the connection support portion to the boss portion, and for fixing the boss portion to the rotating shaft. And a ring-shaped fixture.

The rubber tubular member having the boss portion and the connecting support portion can be integrally formed by vulcanization molding. The cylindrical boss has a center hole that is press-fitted into the rotating shaft. The center hole of the boss has an inner diameter smaller by a predetermined amount than the outer diameter of the rotating shaft so that the center hole can be press-fitted into the rotating shaft. The shape, size, and the like of the connection supporting portion that elastically connects and supports the cylindrical member to the boss portion can be set so as to exhibit desired spring characteristics. For example, the shape of the connection support portion may be a plurality of connection support portions formed at equal intervals in the circumferential direction, or an annular connection support portion extending continuously in the circumferential direction.

The size and shape of the mass member can be appropriately set so that the natural frequency of the dynamic damper can be set to a desired value. The fixing fitting for fixing the boss to the rotating shaft is formed in a ring shape. The ring shape is an O-ring shape having no break in the circumferential direction, and a C-ring shape in which a part in the circumferential direction is cut out. Is also included.

The fixing bracket is arranged so as not to overlap with the connecting support portion in the above-mentioned radial direction (the radial direction of the boss portion; the same applies hereinafter). This is not only the case where the fixing bracket is disposed apart from the connection support portion in the axial direction (the axial direction of the boss portion; the same applies to the following description), and also the case where the fixing bracket is disposed adjacent to the connection support portion in the axial direction. This includes the case where Further, the fixing bracket is disposed at one axial end of the boss. This means that at least the portion where the fixing fitting is not built-in is provided at least at the end on the other end in the axial direction of the boss portion, and in addition to the case where the fixing fitting is arranged at the end on the one end in the axial direction, A case in which a fixing bracket is disposed at a position spaced inward by a predetermined distance from an end on one end in the axial direction, and the end on the one end in the axial direction has a portion in which the fixing bracket is not built in, This also includes the case where the fixture extends from one end in the direction to the other end in the axial direction beyond the center in the axial direction.

Further, the above-mentioned fixing fitting is substantially built in the boss portion so that at least the inner peripheral surface and the outer peripheral surface are covered with rubber constituting the boss portion. This is because when the boss portion is integrally vulcanized and molded while the fixing member is built in the boss portion, the mold surface of the vulcanization mold and the positioning jig are fixed to position and fix the fixing member. Must be in contact with
Since the contact portion with the positioning jig or the like is partially exposed after vulcanization molding, this includes a case where the exposed surface of such a fixing bracket is partially present. In addition, even when the mold surface of the vulcanization mold and the position where the positioning jig abuts at the time of vulcanization molding, the rubber material is fixed to the positioning jig and the like by the injection pressure of the rubber material into the molding die. In some cases, a thin rubber film may be inevitably formed on the exposed surface of the fixture. Further, it is of course possible to cover the surface of the fixing bracket exposed after vulcanization molding positively with a rubber film or the like, and to completely incorporate the fixing bracket in the boss portion so that the exposed surface is completely eliminated.

[0017] The boss portion is configured such that at least an axial end surface of the axial end surface of the fixing bracket at the other end in the axial direction of the boss portion is brought into contact with a positioning jig, and the fixing bracket is placed in a vulcanization mold. It is formed by vulcanization molding in a state where it is positioned in the axial direction. For this reason, in the boss portion after vulcanization molding, a positioning recess extending from the outside to the axial end surface of the fixing bracket is formed at a position where the positioning jig was located at the time of vulcanization molding.

In the case where the fixing bracket is disposed at one end of the boss at the one end in the axial direction, the end surface of the fixing bracket at one end in the axial direction abuts on the mold surface of the vulcanization mold, while the fixing bracket is fixed. The other end face in the axial direction of the metal fitting is brought into contact with the positioning jig. Also,
When the fixing bracket is arranged at a position spaced inward by a predetermined distance from the end of the boss portion on the one end side in the axial direction, both axial end surfaces of the fixing bracket abut on the positioning jig.

At the time of vulcanization molding, the fixing bracket is positioned at at least two places in the circumferential direction. For this reason, at least two positioning recesses are also formed in the circumferential direction.
Further, the side surface of the positioning jig extending in the radial direction of the boss portion may be brought into contact with the axial end surface of the fixing bracket, or the tip end surface of the positioning jig extending in the axial direction of the boss portion may be fixed. You may make it contact the axial end surface of a metal fitting. For this reason, the positioning recess is formed as a hole and a recess extending inward in the radial direction from the outer peripheral surface of the boss, or a groove or a groove extending inward in the axial direction from the axial end surface of the boss. It can be formed as a hole-shaped recess. If the positioning recess is formed as a groove-shaped recess extending in the axial direction, the positioning recess is formed on the inner peripheral surface of the boss.

In this dynamic damper, since the fixing metal for fixing the boss to the rotating shaft is substantially built in the boss, the corrosion resistance of the fixing metal is secured by the reduced exposed surface of the fixing metal. This is advantageous. For this reason, it is possible to suppress an increase in cost due to using an expensive material having high rust-preventive force for the fixing bracket or performing a surface treatment for improving corrosion resistance.

Further, since the fixing bracket is arranged so as not to overlap in the radial direction with the connecting supporting portion for elastically supporting the mass member, the free length of the connecting supporting portion can be reduced without being restricted by the fixing bracket. It can be secured in the radial direction. For this reason, it is advantageous in terms of the strength of the connection support portion and the characteristic design of the dynamic damper. Further, the attachment to the rotating shaft is performed by press-fitting the rotating shaft into the center hole of the boss portion. However, since the fixing fitting for fixing the boss portion to the rotating shaft is built in the boss portion, the boss portion is mounted. After the rotary shaft is press-fitted into the center hole of the portion, there is no need to separately fasten a stainless steel band or the like, and the mounting work becomes easy.

Further, a rubber portion of the boss portion (hereinafter referred to as a restricted rubber portion) which is located radially inside the ring-shaped fixture and whose outer peripheral surface is restricted by the fixture is compressed by elastic deformation. Allows for press-fitting to the rotating shaft. For this reason, as the constrained rubber portion is thicker in the radial direction, and thus the distortion at the time of press-fitting in the constrained portion becomes smaller, the force required for press-fitting becomes smaller, and the press-fitting property to the rotating shaft can be improved.

In this regard, in the dynamic damper according to the first aspect, since the fixing bracket and the connection support are not laminated in the radial direction, the free length of the connection support is provided for reasons such as securing the strength of the connection support. Even if is made longer in the radial direction, the constrained rubber portion does not become thinner in the radial direction. Therefore, it is advantageous to improve the press fit into the rotating shaft.

Further, in the dynamic damper according to the first aspect, since the fixing bracket is disposed at one axial end of the boss, the other axial end of the boss extends radially outward. The deformation is not restricted by the fixing bracket. For this reason, when press-fitting the rotary shaft, the other end in the axial direction of the boss is radially moved out of the other end in the axial direction of the boss by press-fitting the rotary shaft from the other end in the axial direction of the boss having no built-in fixture. Pressing can be performed while being deformed in the direction, which is more advantageous for improving press-fitting.

Here, if the fixing bracket is displaced in the axial direction from the predetermined position and is incorporated in the boss, there is a possibility that the spring characteristic of the connecting support formed integrally with the boss may be adversely affected. For example, when the fixing bracket is displaced in the axial direction from the predetermined position toward the connection supporting section, the spring characteristic of the connecting supporting section may be harder than desired due to the influence of the rigidity of the fixing bracket. For this reason, when vulcanizing and molding the boss while incorporating the fixture, it is necessary to reliably position the fixture in the axial direction with respect to the boss.

In this regard, in the dynamic damper according to the first aspect, the boss portion makes at least the axial end surface of the axial end surface of the fixing bracket at the other axial end of the boss portion abut on the positioning jig. Then, the fixing bracket is formed by vulcanization molding in a state of being positioned in the vulcanization mold in the axial direction. For this reason, the fixture can be built in the boss in a state where it is securely positioned in the axial direction with respect to the boss. Therefore, the fixing bracket does not shift from the predetermined position in the axial direction, and it is possible to reliably prevent a variation in the spring characteristic of the connection support portion due to the axial shift. (2) The dynamic damper according to the second aspect is the first aspect.
In the dynamic damper described above, a plurality of the connection support portions are formed at equal intervals in a circumferential direction, and at least two positioning recesses are formed at intervals in a circumferential direction. And each positioning recessed part is arrange | positioned so that it may correspond to the space between adjacent connection support parts and a circumferential direction.

When the positioning recess is formed in the boss, the rubber volume of the boss is reduced by the volume of the positioning recess, and the boss is expected due to the presence of the positioning recess when the rotary shaft is pressed into the boss. Undesirable deformation may occur. For this reason, if the positioning concave portion is formed at a position corresponding to the circumferential direction with the connecting support portion formed at intervals in the circumferential direction, there is a possibility that the spring characteristics of the connecting maintaining portion may be adversely affected.

In this regard, in the dynamic damper according to the second aspect, each positioning concave portion is disposed so as to correspond to a space between adjacent coupling support portions in the circumferential direction. For this reason, it is possible to suppress the variation in the spring characteristics of the connection support portion based on the positioning recess.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the dynamic damper of the present invention will be specifically described with reference to the drawings. In addition,
The following dynamic damper is mounted on a drive shaft of an automobile. (Embodiment 1) The dynamic damper shown in FIGS. 1 and 2 includes a cylindrical member 1 made of rubber, a mass member 2 made of metal, and a fixture 3. In addition, FIG.
2 is a right side view as viewed from the right side of FIG. 1. FIG. In the following description, the axial direction refers to the axial direction of the tubular member 1 and a boss 4 described below, and the radial direction refers to the radial direction of the tubular member 1 and the boss 4 described later. The direction means a circumferential direction of the tubular member 1 and a boss 4 described later. Further, one axial end means the left side in FIG. 1 and the other axial end means the right side in FIG.

The cylindrical member 1 is formed integrally with a substantially cylindrical boss portion 4 having a center hole 4a into which a drive shaft (not shown) as a rotating shaft is press-fitted, and on the outer surface of the boss portion 4. Five connection support parts 5 arranged at equal intervals in the circumferential direction
And The connection support portion 5 projects radially outward from a substantially central portion of the boss portion 4 in the axial direction. The mass member 2 has an inner diameter larger than the outer diameter of the boss portion 4, and is a thick cylindrical member having an axial length substantially half the axial length of the boss portion 4. It is arranged coaxially with the boss 4 outside the other end in the radial direction. The axial end of the mass member 2 and the axial end of the boss 4 coincide with each other in the axial direction. One end of the mass member 2 in the axial direction is elastically connected to and supported by the connection support portion 5 with respect to the boss portion 4.

The mass member 2 is covered with a rubber film 6 formed integrally with the connection supporting portion 5. And
The rubber film 6 formed radially inside the mass member 2 includes:
Five stopper rubber portions 7 each having a large thickness are provided integrally so as to protrude radially inward in each space between the adjacent connection support portions 5. The stopper rubber portion 7 is for restricting the mass member 2 from being excessively displaced in the radial direction with respect to the boss portion 4 due to the contact with the boss portion 4. Note that the surface of the rubber film 6 formed on the end face of the mass member 2 at one end in the axial direction and the end face of one end in the axial direction of the connection support portion 5 are flush with each other.

The fixing member 3 is formed in a thin O-ring shape with no break in the circumferential direction, and is axially separated from the connecting support portion 5 so as not to overlap in the radial direction, specifically, the shaft of the boss portion 4. It is substantially built into one end on one side in the direction. An end face on one end side in the axial direction of the fixing bracket 3 is exposed on an end face on one end side in the axial direction of the boss portion 4. Further, in the portion where the fixing fitting 3 is built, the boss portion 4 is made thicker by the thickness of the fixing fitting 3.

In the dynamic damper having such a configuration, a rubber material is injected and filled into a vulcanization mold in a state where the mass member 2 and the fixing fitting 3 are arranged at predetermined positions in the vulcanization mold, so that the boss portion is formed. The rubber member 6 can be manufactured by integrally vulcanizing the cylindrical member 1 including the connecting member 4 and the connecting support portion 5 and the rubber film 6. Here, the positioning and fixing of the mass member 2 are performed at the other end side in the axial direction by four positioning holes 2 recessed at equal intervals in the circumferential direction on the end surface of the mass member 2.
a (see FIG. 2), four pins (not shown) projecting from the vulcanizing mold are engaged with each other, and a shoulder part partially protruding from the vulcanizing mold at one end in the axial direction. (Not shown) is made to contact the outer end of the mass member 2 at four locations at equal intervals in the circumferential direction. After the vulcanization molding, the rubber film 6 has four through holes 6a (see FIG. 2) in the portion where the pins existed, and four cuts in the portion where the shoulders existed. A notch 6b (see FIG. 1) is formed.

The positioning and fixing of the fixture 3 are performed as follows.
At the other end in the axial direction, part of the end face of the fixture 3 (upper two locations and lower one location; see FIG. 2) is protruded from the vulcanization mold so as to extend in the radial direction of the boss portion 4. This is performed by abutting a positioning jig (not shown) and an end surface of the fixing bracket 3 on one end side in the axial direction with a mold surface of a vulcanization mold.

Here, after the vulcanization molding, the boss 4 is attached to the portion where the positioning jig was present.
Three through-holes (positioning concave portions) 4b extending from the outer peripheral surface to the end surface of the fixing bracket 3 inward in the radial direction are formed. And these three through-holes 4b are arrange | positioned so that it may correspond to the space between the adjacent connection support parts 5, and a circumferential direction.

In the dynamic damper according to the present embodiment having the above-described configuration, the fixture 3 for fixing the boss 4 to the drive shaft is substantially built in the boss 4. That is, the portion where the fixing metal 3 is exposed is only the end face of the other end of the fixing metal 3 in the axial direction and the portion of the through hole 4 b, and the other portions are covered with the rubber of the boss portion 4. For this reason, it is advantageous to secure the corrosion resistance of the fixture 3 by the amount of the exposed surface of the fixture 3 being reduced. Therefore, an expensive material having high rust prevention is used for the fixing bracket 3,
Alternatively, it is possible to suppress a rise in cost due to performing a surface treatment for improving corrosion resistance.

Further, since the fixing bracket 3 is arranged so as not to overlap in the radial direction with the connecting supporting section 5 for elastically supporting the mass member 2, the connecting supporting section is not restricted by the fixing bracket 3. 5 can be secured in the radial direction. This is advantageous in terms of the strength of the connection support portion 5 and the characteristic design of the dynamic damper. Further, the attachment to the drive shaft is performed by press-fitting the drive shaft into the center hole 4a of the boss portion 4, and a fixture 3 for fixing the boss portion 4 to the drive shaft is built in the boss portion 4. Therefore, after the drive shaft is pressed into the center hole 4a of the boss portion 4,
There is no need to separately fasten a stainless steel band or the like, which facilitates the mounting operation.

Further, since the fixing member 3 and the connection supporting portion 5 are not laminated in the radial direction, the boss portion is located inside the ring-shaped fixing member 3 in the radial direction and the outer peripheral surface is restrained by the fixing member 3. Even if the free length of the connecting support 5 is increased in the radial direction for reasons such as securing the strength of the connecting support 5, the restraint rubber portion 4d does not become thinner in the radial direction. . For this reason, the restraining rubber portion 4
This is advantageous in securing the radial thickness d and improving the press fit into the drive shaft.

Further, since the fixing member 3 is disposed at one axial end of the boss 4, the other end of the boss 4 at the other axial end is prevented from deforming outward in the radial direction. You will not be bound. For this reason, when press-fitting into the drive shaft, the other end in the axial direction of the boss portion 4 is pressed into the drive shaft from the other end in the axial direction of the boss portion 4 in which the fixing fitting 3 is not incorporated. Press-fitting can be performed while deforming outward in the radial direction, which is more advantageous for improving press-fitting properties.

During vulcanization of the boss 4 and the connecting support 5 and the like, the fixing bracket 3 has one end in the axial direction abutting on the mold surface of the vulcanizing mold and the other end in the axial direction. The end surface abuts on the positioning jig, whereby the boss portion 4 is reliably positioned in the axial direction. For this reason, in this embodiment, the fixture 3 can be built in the boss 4 in a state where it is securely positioned in the axial direction with respect to the boss 4. Therefore, the fixing bracket 3 is not displaced in the axial direction from the predetermined position, and it is possible to reliably prevent a variation in the spring characteristic of the connection support portion 5 due to the axial displacement.

Further, the three through holes 4b formed at intervals in the circumferential direction are arranged so as to correspond to the space between the adjacent connection support portions 5 in the circumferential direction. For this reason, compared with the case where the through-hole 4b is arrange | positioned so that it may correspond to the connection support part 5 in the circumferential direction, it is possible to suppress the variation of the spring characteristic in the connection support part 5 based on the presence of the through-hole 4b. Become.

(Embodiment 2) FIGS. 3 to 5 show a dynamic damper of this embodiment. 3 is a cross-sectional view taken along line BB in FIG. 4 and line CC in FIG. 5, FIG. 4 is a right side view as viewed from the right side in FIG. 3, and FIG. 5 is a view as viewed from the left side in FIG. FIG. In this dynamic damper, the connection supporting portion for elastically connecting and supporting the mass member 2 to the boss portion 4 includes three connection supporting portions 5A for connecting and supporting one end of the mass member 2 on one axial side, and a mass. Two connection support portions 5B for connecting and supporting the other end of the member 2 in the axial direction are provided. The two connection support portions 5A and the three connection support portions 5B are arranged alternately in the circumferential direction.

In this embodiment, two through holes 4b as positioning recesses are formed in the circumferential direction at an interval of 180 degrees (see FIG. 4), and one through hole 4b (upper side in FIG. 4). Is disposed at a position corresponding to the circumferential direction of the connecting support portion 5A, and the other through hole 4b (lower side in FIG. 4) is positioned at a position corresponding to the space between the adjacent connecting support portions 5A and the circumferential direction. ing.

Other structures are substantially the same as those of the first embodiment. In the above-described dynamic damper of the first embodiment, since all the five connection support portions 5 are configured to connect and support one axial end of the mass member 2, the center of gravity of the mass member 2 and the center of gravity of the connection support portion 5 are provided. Are shifted in the axial direction, and resonance (harmful vibration) such as a twisting mode may occur.

In this regard, in the dynamic damper of the present embodiment, three connection support portions 5A for connecting and supporting one end in the axial direction of the mass member 2 and the other end in the axial direction of the mass member 2 are connected. Since the two connecting support portions 5B to be supported are alternately arranged in the circumferential direction, the axial displacement between the center of gravity of the entire five connecting support portions 5A and 5B and the center of gravity of the mass member 2 is reduced. And the resonance such as the twisting mode can be suppressed.

Other functions and effects are substantially the same as those of the first embodiment. In the dynamic damper of the present embodiment, one of the through holes 4b is disposed at a position corresponding to the connecting support portion 5A in the circumferential direction, so that the connection supporting portion 5A is affected by the through hole 4b. The spring characteristics may vary. (Embodiment 3) FIGS. 6 and 7 show a dynamic damper of this embodiment. 6 is a cross-sectional view taken along line DD of FIG. 7, and FIG. 7 is a right side view as viewed from the right side of FIG.

In this dynamic damper, the mass member 2
Is connected to and supported by the five connection support portions 5 with respect to the boss portion 4. For this reason, the center of gravity of the mass member 2 and the center of gravity of the connection support portion 5 are axially coincident with each other, and there is no possibility of causing resonance (harmful vibration) such as a twisting mode. Further, in this dynamic damper, the cylindrical member 1 composed of the boss portion 4 and the connecting support portion 5 and the rubber film 6 are integrally formed in a state where the mass member 2 and the fixing bracket 3 are arranged at predetermined positions in the vulcanization mold. When vulcanization molding is performed, the positioning and fixing of the fixture 3 are performed by bringing the end face of one end in the axial direction of the fixture 3 into contact with the mold surface of one of the split dies and the other end of the fixture 3 in the axial direction. A part of the end face (two upper parts and one lower part; see FIG. 7) is brought into contact with three positioning jigs projecting from the other divided mold so as to extend in the axial direction. Will be

Here, after the vulcanization molding, the inner surface of the boss portion 4 is placed on the inner surface of the boss portion 4 at the portion where the positioning jig was present, from the other end surface of the fixture 3 in the axial direction. Three grooves (positioning recesses) 4e, 4e, and 4e extending in the axial direction to the end side end are formed. These three grooves 4e, 4e, 4e are arranged so as to correspond to the space between the adjacent connection support portions 5 in the circumferential direction.

The other structure is substantially the same as that of the first embodiment. In the case where the grooves 4e, 4e, and 4e as positioning recesses are formed in the inner peripheral surface of the boss 4 so as to extend in the axial direction as in this embodiment, the grooves 4e are temporarily The position corresponding to the direction, that is, I groove 4
When e is arranged at a position radially overlapping with the connection support portion 5, the spring characteristics of the connection support portion 5 are easily affected by the groove 4e.

In this regard, in the present embodiment, three private grooves 4
Since e, 4e, and 4e are arranged so as to correspond to the space between the adjacent connection support portions 5 in the circumferential direction,
It is possible to effectively suppress the variation in the spring characteristics of the connection support portion 5 due to the presence of the through groove 4e. Other functions and effects are substantially the same as those of the first embodiment.

(Embodiment 4) FIGS. 8 to 10 show a dynamic damper of this embodiment. 8 is a cross-sectional view taken along the line EE in FIG. 9 and the line FF in FIG. 10, FIG. 9 is a right side view as viewed from the right side of FIG. 8, and FIG. FIG. In this dynamic damper, the mass member 2
Is disposed at the center of the boss 4 in the axial direction.
Is connected to and supported by the five elastic support portions 5 with respect to the boss portion 4.

The fixing fitting 3 built in the one end of the boss 4 in the axial direction is slightly longer in the axial direction than half the axial length of the boss 4, It extends from the side end beyond the center in the axial direction to the other end in the axial direction. Further, in this dynamic damper, with the mass member 2 and the fixing fitting 3 arranged at predetermined positions in the vulcanization mold, the cylindrical member 1 composed of the boss portion 4 and the connection support portion 5 and the rubber film 6 are integrally formed. When vulcanization molding is performed, the positioning and fixing of the fixture 3 are performed by bringing the end face of one end in the axial direction of the fixture 3 into contact with the mold surface of one of the split dies and the other end of the fixture 3 in the axial direction. Part of the end face of (2 upper parts and one lower part.
FIG. 9) shows three inclined protruding portions (positioning jigs formed integrally with the cylindrical medium) which partially protrude from the outer surface of the cylindrical medium to define the center hole 4a of the boss portion 4. This is performed by abutting on the vertical end face.

Here, after the vulcanization molding, the inner surface of the boss portion 4 has a portion on the inner surface of the boss portion 4 where the above-mentioned inclined protruding die portion was present. Three inclined grooves (positioning recesses) 4f, 4f, 4f extending in the axial direction to near the other end are formed. The three inclined grooves 4f, 4f, 4f are arranged so as to correspond to the space between the adjacent connection support portions 5 in the circumferential direction.

Other structures are substantially the same as those in the first embodiment. This dynamic damper has substantially the same effect as the dynamic damper of the third embodiment. (Embodiment 5) The dynamic damper of this embodiment is shown in FIGS.
As shown in FIG. 11 is a sectional view taken along line GG of FIG. 12 and an arrow HH of FIG. 13, FIG. 12 is a right side view as viewed from the right side of FIG. 11, and FIG. 13 is a view as viewed from the left side of FIG. FIG.

This dynamic damper is an improvement of the dynamic damper of the second embodiment described above.
The vulcanization is carried out such that at the other end in the axial direction, part of the end face of the fixing bracket 3 (two upper parts and one lower part; see FIG. 13) extends in the radial direction of the boss part 4. This is performed by abutting on a positioning jig (not shown) protruding from the molding die, and at one end in the axial direction, by contacting the end surface of the fixture 3 with the mold surface of the vulcanization molding die. .

Here, after the vulcanization molding, the boss portion 4 is attached to the portion where the positioning jig was present.
Three through-holes (positioning concave portions) 4b extending from the outer peripheral surface to the end surface of the fixing bracket 3 inward in the radial direction are formed. And these three through-holes 4b are arrange | positioned so that it may correspond to the space between the adjacent connection support parts 5, and a circumferential direction.

The other structure is substantially the same as that of the second embodiment. In this dynamic damper, the three through holes 4b formed at intervals in the circumferential direction are arranged so as to correspond to the space between the adjacent connection support portions 5 in the circumferential direction. For this reason, the through hole 4b is
And compared to the case where it is arranged to correspond to the circumferential direction,
It is possible to suppress the variation in the spring characteristics of the connection support portion 5 due to the presence of the through hole 4b.

Other functions and effects are substantially the same as those of the second embodiment.

[0059]

As described in detail above, in the dynamic damper of the present invention, since the fixing bracket is substantially built in the boss portion, the cost of the fixing bracket can be reduced, and the dynamic damper can be mounted on the rotating shaft. It is possible to improve the workability of the mounting. In addition, since the fixing bracket is arranged so as not to overlap the connecting support part in the radial direction, the free length of the connecting support part can be secured in the radial direction without being restricted by the fixing metal, and the connecting supporting part can be secured. This is advantageous in terms of strength and characteristic design of the dynamic damper.

Further, since the fixing fitting is disposed at one end in the axial direction of the boss, the boss having no fixing fitting is pressed into the rotary shaft from the other end in the axial direction of the boss. Is easily displaced outward in the radial direction, and the press-fitting property to the rotating shaft can be improved. In addition, since the fixing bracket is securely positioned in the axial direction and is incorporated in the boss, it is possible to reliably prevent the spring characteristics of the connection supporting portion from varying due to the axial displacement of the fixing bracket.

Further, when the positioning recesses are arranged so as to correspond to the space between the adjacent connection supporting portions in the circumferential direction, it is possible to suppress the variation in the spring characteristics of the connection supporting portions based on the positioning recesses. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of the dynamic damper according to a first embodiment, taken along line AA of FIG. 2;

FIG. 2 is a right side view of the dynamic damper according to the first embodiment as viewed from the right side in FIG. 1;

FIG. 3 is a cross-sectional view of the dynamic damper according to the second embodiment, taken along line BB in FIG. 4 and line CC in FIG. 5;

FIG. 4 is a right side view of the dynamic damper according to the second embodiment as viewed from the right side in FIG. 3;

FIG. 5 is a left side view of the dynamic damper according to the second embodiment, viewed from the left side of FIG. 3;

FIG. 6 is a cross-sectional view of the dynamic damper according to the third embodiment, taken along line DD in FIG. 7;

FIG. 7 is a right side view of the dynamic damper according to the third embodiment as viewed from the right side in FIG. 6;

8 is a cross-sectional view of the dynamic damper according to the fourth embodiment, taken along line EE in FIG. 9 and line FF in FIG. 10;

FIG. 9 is a right side view of the dynamic damper according to the fourth embodiment as viewed from the right side in FIG. 8;

FIG. 10 relates to a dynamic damper according to a fourth embodiment, and
5 is a left side view as viewed from the left side of FIG.

FIG. 11 relates to a dynamic damper according to a fifth embodiment, and
FIG. 14 is a sectional view taken along line GG of FIG. 2 and line HH of FIG. 13.

FIG. 12 relates to a dynamic damper of a fifth embodiment,
1 is a right side view as viewed from the right side of FIG.

FIG. 13 relates to a dynamic damper of a fifth embodiment,
1 is a left side view as viewed from the left side of FIG.

FIG. 14 is a longitudinal sectional view of a conventional dynamic damper.

FIG. 15 is a longitudinal sectional view of another conventional dynamic damper.

[Explanation of symbols]

In the figure, 1 is a cylindrical member, 2 is a mass member, 3 is a fixing bracket, 4 is a boss portion, 4a is a center hole, 5, 5A and 5B are connection support portions,
Reference numeral 6 denotes a rubber film, 7 denotes a stopper rubber portion, 4b denotes a through hole as a positioning recess, 4e denotes a groove as a positioning recess, and 4f denotes an inclined groove as a positioning recess.

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Toru Mabuchi 19, Matsuyama-cho, Moka-shi, Tochigi Honda Motor Co., Ltd.

Claims (2)

[Claims] 1. A rubber-made cylindrical member having a cylindrical boss having a center hole into which a rotating shaft is press-fitted, and a connecting support formed integrally with an outer surface of the boss; A ring-shaped mass member disposed radially outward and elastically connected and supported by the connection support portion to the boss portion; and a ring-shaped fixture for fixing the boss portion to the rotation shaft. The fixing fitting is disposed at one axial end of the boss so as not to overlap with the connection support in the radial direction, and at least an inner peripheral surface and an outer peripheral surface constitute a boss. The boss portion is substantially built into the boss portion so as to be covered by the boss portion, and the boss portion contacts at least an axial end surface of the axial end surface of the fixing bracket at the other axial end side of the boss portion with a positioning jig. Vulcanization molding The boss portion is formed by vulcanization molding in a state of being positioned in the axial direction. The boss portion has a positioning recess extending from the outside to the axial end surface of the fixing bracket, and is provided with the positioning jig during vulcanization molding. A dynamic damper characterized in that it is formed in a bent part. 2. A plurality of the connecting support portions are formed at equal intervals in a circumferential direction, and at least two positioning recesses are formed at a circumferential interval. Each of the positioning recesses is adjacent to each other. The dynamic damper according to claim 1, wherein the dynamic damper is disposed so as to correspond to a space between the connection supporting portions in a circumferential direction.