JP7390872B2 - Dynamic damper and its manufacturing method - Google Patents

Description

The present invention relates to a dynamic damper that absorbs torsional vibrations generated in a rotational drive system such as a propeller shaft of an internal combustion engine, and a method for manufacturing the dynamic damper. Dynamic dampers are sometimes called Tilgars.

Rear-wheel drive or four-wheel drive automobiles are equipped with a propeller shaft to transmit the output of an internal combustion engine mounted at the front of the vehicle to the rear wheels.
Since the vibrations generated in the propeller shaft have a large effect on vehicle vibrations, the propeller shaft is equipped with a dynamic damper that dampens the vibrations.

The dynamic damper includes a hub, a vibration ring located on the outer peripheral side of the hub, and an elastic body that connects the hub and the vibration ring. By resonating the vibration ring and the elastic body so as to cancel out vibrations when the propeller shaft rotates, vibrations in the torsional direction (rotation direction) of the propeller shaft can be attenuated.

In recent years, as vehicles have been made lighter to improve fuel efficiency, the frequency band of vibrations generated in propeller shafts has become lower. As the frequency of vibration decreases, the excitation input value to the dynamic damper tends to increase, and there is a possibility that a large torsional load will be applied to the elastic body.
Here, if the elastic body is made longer in the radial direction, the durability of the elastic body is improved. However, in that case, the radial space of the dynamic damper increases. Furthermore, if a stopper is provided to restrict the amount of relative displacement of the vibrating ring, torsional loads on the elastic body can be prevented, but the provision of the stopper results in an increase in the number of parts.

In order to solve the above problems, a dynamic damper described in Patent Document 1 was proposed.
As shown in FIG. 10, Patent Document 1 describes a hub 20, a vibration ring 30 located on the outer peripheral side of the hub 20, a vibration ring 30 located on both sides of the vibration ring 30 in the axial direction, and a vibration ring 30 located on the outer peripheral side of the hub 20. A pair of elastic bodies 40 made of a rubber-like elastic body are connected to the ring 30, and the vibrating ring 30 includes a convex portion 32 that extends to near the outer periphery of the hub 20. 20 to the vibration ring 30 and curved outward in the axial direction from the convex part 32 , and the surface of the elastic body 40 on the convex part 32 side is made of a rubber-like elastic body that extends toward the convex part 32 . A dynamic damper 10 is described in which a protrusion 44 is integrally molded, and a gap is set between the protrusion 32 and the protrusion 44. Further, the vibration ring 30 in such a dynamic damper 10 has an annular vibration ring main body 31 connected to the outer peripheral side of the hub 20 via a sleeve 41 and an elastic body 40. It is described that a convex portion 32 is formed from the center toward the inner diameter direction. Further, it is described that a dry bearing 33 is fitted onto the inner peripheral surface of the convex portion 32.
According to such a dynamic damper 10, by forming the elastic body 40 into a curved shape, the torsional load on the elastic body 40 can be reduced without increasing the radial space in which the elastic body 40 is provided. It is described that the relative displacement amount of the vibration ring 30 can be attenuated by the resistance when the protrusion 44 contacts the convex part 32, and it can also function as a stopper.

International Publication No. 2018/088103 pamphlet

When assembling the dynamic damper 10 described in Patent Document 1 as described above, one elastic body 40 is fitted between the hub 20 and the vibration ring main body 31, and then the other elastic body 40 is inserted between the hub 20 and the vibration ring. It fits between the main body 31. Here, when fitting the elastic body 40 so as to sandwich the convex part 32 of the vibration ring 30 from both sides in the axial direction, it is impossible to fit (press-fit) the elastic body 40 even if stress is applied to the elastic body 40. One end is fixed to the cylindrical sleeve 41, and then stress is applied to the sleeve 41 to fit it.
However, as in the embodiment shown in FIG. 10, if the end of the curved portion 42 is fixed to the end face perpendicular to the axis of the sleeve 41, it is possible to fit (press fit) by applying stress to this end face. Can not. This is because there is a possibility that the end portion of the curved portion 42 may be damaged. If the end of the curved portion 42 is damaged, the elastic body 40 will not be able to exhibit its desired performance, and as a result, the torsional load on the elastic body 40 will not be reduced, and in addition, the stopper function of the protrusion 44 will be impaired. It becomes difficult to perform effectively.

The present invention aims to solve the above problems. That is, an object of the present invention is to provide a dynamic damper that can suppress damage to an elastic body and deformation of a sleeve, and a method for manufacturing the dynamic damper.

The present inventor has made extensive studies to solve the above problems and has completed the present invention.
The present invention includes the following (1) to (3).
(1) Comprising a hub, a vibration ring, a pair of elastic bodies, a bearing, and a pair of sleeves on the outer diameter side and the inner diameter side ,
The vibration ring is disposed on the outer peripheral side of the hub, and has an annular vibration ring main body and a convex portion protruding toward the outer peripheral surface of the hub on the inner peripheral side thereof,
The pair of elastic bodies are arranged to sandwich the convex portion of the vibration ring from both sides in the axial direction, connect the hub and the vibration ring main body via the sleeve, and curve outward in the axial direction. a curved portion; and a protrusion protruding from the inner surface of the curved portion toward the convex portion,
The bearing is a dynamic damper disposed between the convex portion and the hub,
Each of the pair of sleeves has a cylindrical shape, and has a cylindrical portion forming an inner cylindrical surface parallel to the axial direction and a flange portion , and the flange portion of the sleeve on the outer diameter side is located at one end of the cylindrical portion. The flange portion of the sleeve on the inner diameter side projects toward the inner circumference side from one end of the cylindrical portion, and the inner diameter side of the curved portion of the elastic body and A dynamic damper, wherein each of the ends on the outer diameter side is fixed only to the inner cylindrical surface of the sleeve on the inner diameter side and the outer diameter side .
(2) The dynamic damper according to (1) above, wherein the flange portion of the sleeve has a guide portion.
(3) Fixing to obtain a sleeved elastic body by fixing each of the ends of the curved portion of the elastic body only to the inner cylindrical surface of each of the two sleeves arranged on the inner diameter side and the outer diameter side. process and
The sleeved elastic body is placed on a jig that supports at least a portion of the stress applied to the cylindrical portion from below via the flange portion, and the inner cylindrical surface is in the vertical direction and the flange portion is on the lower side. a first press-fitting step of placing the
In the first press-fitting step, the hub is fitted from above into the sleeve on the inner circumference side of the sleeved elastic body disposed on the jig, and the hub is fitted from above into the sleeve on the outer circumference side of the sleeved elastic body. a second press-fitting step of fitting the vibration ring from the
Using a jig that can apply stress to the cylindrical part through the flange part, another elastic body with a sleeve is attached with the inner cylindrical surface facing vertically and with the flange part facing upward. , a third press-fitting step of press-fitting between the hub and the vibration ring main body from above;
A method for manufacturing a dynamic damper, which comprises: obtaining the dynamic damper according to (1) or (2) above.

According to the present invention, it is possible to provide a dynamic damper that can suppress damage to an elastic body and deformation of a sleeve, and a method for manufacturing the dynamic damper.

FIG. 2 is a schematic cross-sectional view in the axial direction of the dynamic damper of the present invention. FIG. 3 is a schematic plan view in a direction perpendicular to the axis of the dynamic damper of the present invention. FIG. 4 is a schematic cross-sectional perspective view of a sleeve 41a on the outer diameter side and a sleeve 41b on the inner diameter side. 4 is a schematic cross-sectional perspective view showing a state in which an elastic body 40 is fixed to the two sleeves shown in FIG. 3. FIG. It is a schematic perspective view which shows the suitable example of the jig used in a 1st press-fitting process. It is a schematic partial sectional view for explaining the 1st press-fitting process. It is a schematic partial cross-sectional view for demonstrating a 2nd press-fitting process. It is a schematic perspective view which shows the suitable example of the jig used in a 3rd press-fitting process. It is a schematic partial cross-sectional view for demonstrating a 3rd press-fitting process. FIG. 2 is a schematic cross-sectional view in the axial direction of a conventional dynamic damper.

The present invention will be explained.
The present invention includes a hub, a vibration ring, a pair of elastic bodies, a bearing, and a sleeve, and the vibration ring is arranged on the outer circumference side of the hub, and includes an annular vibration ring main body and an inner circumference side thereof. has a convex portion protruding toward the outer circumferential surface of the hub, and the pair of elastic bodies are arranged to sandwich the convex portion of the vibrating ring from both sides in the axial direction, and the pair of elastic bodies are arranged to sandwich the convex portion of the vibrating ring from both sides in the axial direction. and a curved portion that curves outward in the axial direction, and a protrusion that protrudes from the inner surface of the curved portion toward the convex portion, and the bearing is connected to the convex portion through the sleeve. and the hub, the sleeve has a cylindrical shape, and includes a cylindrical portion forming an inner cylindrical surface parallel to the axial direction, and an outer periphery from one end of the cylindrical portion. a flange portion protruding toward the side, and each of the inner diameter side and outer diameter side ends of the curved portion of the elastic body is fixed only to the inner cylindrical surface of the sleeve. It is.
Such a dynamic damper is also referred to below as "the dynamic damper of the present invention".

Further, the present invention provides a sleeved elastic body by fixing each of the ends of the curved portion of the elastic body only to the inner cylindrical surface of each of the two sleeves disposed on the inner diameter side and the outer diameter side. The sleeved elastic body is placed on a jig that supports at least a portion of the stress applied to the cylindrical portion from below via the flange portion, and the inner cylindrical surface is in the vertical direction. a first press-fitting step in which the flange portion is placed on the lower side; and a first press-fitting step in which the hub is inserted from above into the sleeve on the inner peripheral side of the sleeved elastic body placed on the jig. a second press-fitting step of fitting the vibrating ring into the sleeve on the outer peripheral side of the sleeved elastic body from above; and a jig capable of applying stress to the cylindrical portion via the flange portion. A third elastic body is press-fitted between the hub and the vibration ring main body from above with the inner cylinder surface facing vertically and the flange portion facing upward. This is a method for manufacturing a dynamic damper, which includes a press-fitting step and obtains the dynamic damper of the present invention.
The method for manufacturing such a dynamic damper is also referred to below as the "manufacturing method of the present invention."

The dynamic damper of the present invention can be obtained by the manufacturing method of the present invention.
The dynamic damper of the present invention is preferably manufactured by the manufacturing method of the present invention.

Preferred embodiments of the dynamic damper of the present invention will be explained using FIGS. 1 to 4. FIG. 1 is a schematic sectional view in the axial direction of a preferred embodiment of the dynamic damper of the present invention, and FIG. 2 is a schematic plan view in the direction perpendicular to the axis of the dynamic damper of the present invention shown in FIG. . 3 is a schematic cross-sectional perspective view of the outer sleeve 41a and the inner sleeve 41b, and FIG. 4 is a schematic cross-sectional perspective view showing the elastic body 40 fixed to the two sleeves shown in FIG. It is.

Note that FIGS. 1 to 4 and FIGS. 5 to 9, which will be described later, are examples of preferred embodiments of the dynamic damper of the present invention. The dynamic damper of the present invention is not limited to the embodiments shown in FIGS. 1 to 9. The present invention allows various modifications and changes.

As shown in FIGS. 1 and 2, the dynamic damper 10 includes a cylindrical hub 20 and a cylindrical vibration ring 30 located on the outer peripheral side of the hub 20. The bodies 40 are connected. A pair of elastic bodies 40 are provided on both sides of the vibration ring 30 in the axial direction. This dynamic damper 10 is used by being attached to a propeller shaft or the like located on the lower side of a vehicle such as an automobile.

The hub 20 is fixed to the propeller shaft. The outer peripheral surface 21 of the hub 20 is connected to the vibration ring 30 via an elastic body 40.

The vibrating ring 30 has an annular vibrating ring body 31. The vibration ring main body 31 is connected to the outer peripheral side of the hub 20 via a sleeve 41 (41a, 41b) and an elastic body 40. Further, the vibration ring 30 has a convex portion 32 extending from its axial center toward the inner diameter direction. A dry bearing 33 is fitted and fixed to the inner circumferential surface of the convex portion 32. The inner circumferential surface of the dry bearing 33 faces the outer circumferential surface 21 of the hub 20 with a slight gap therebetween. That is, a minute gap is set between the inner peripheral surface of the dry bearing 33 and the outer peripheral surface 21 of the hub 20.

The elastic body 40 is an annular rubber-like elastic body. The elastic body 40 includes a curved portion 42 that is curved outward in the axial direction (in the left-right direction in FIG. 1). The curved portion 42 has an annular rubber lump 43 at the center portion of the outer surface (the apex of the curved portion 42), and has an annular protrusion 44 at the center portion of the inner surface of the curved portion 42.

The rubber mass 43 is formed at the center of the outer surface of the curved portion 42 located on the opposite side from the protrusion 44 . A portion of the curved portion 42 where the rubber mass 43 is located is thick, and the elastic body 40 increases the rigidity of the rubber mass 43 portion.
In addition, in the dynamic damper of the present invention, the position of the rubber mass 43 in the elastic body 40 is not particularly limited. However, in order to elastically deform the outer diameter side and the inner diameter side of the elastic body 40 in a well-balanced manner, it is preferable that the rubber mass 43 is arranged at the center of the elastic body 40, that is, near the apex of the curved portion 42. .

The protrusion 44 is formed at the center of the inner surface of the curved portion 42, which is located on the opposite side of the rubber mass 43. The protruding portion 44 extends in the axial direction from the inner surface of the curved portion 42 toward the convex portion 32 of the vibration ring 30. A minute gap C1 is provided between the tip of the protrusion 44 and the convex portion 32. The gap C1 is approximately 1 to 2 mm.

The outer end 42a and the inner end 42b of the curved portion 42 of the elastic body 40 are fixed to cylindrical sleeves 41a and 41b, as shown in FIGS. 1 and 4. .

As shown in FIGS. 3 and 4, the sleeve 41a includes a cylindrical portion α that constitutes an inner cylindrical surface _X1 parallel to the axial direction, and a flange that protrudes from one end of the cylindrical portion α toward the outer circumference. It has a part β. Here, it is preferable that the flange portion β has a guide portion γ. Although the flange portion β is connected to the cylindrical portion α at one end, it is preferable that the flange portion β is connected to the guide portion γ at the other end. As shown in FIGS. 3 and 4, the guide portion γ preferably extends in a direction parallel to the axial direction.
When the flange portion β has the guide portion γ, positioning of the jig becomes easier during the manufacturing process, contributing to improvement in work efficiency during the manufacturing process.

The outer diameter side end 42a of the curved portion 42 of the elastic body 40 is fixed only to the inner cylindrical surface _X1 parallel to the axis of the cylindrical portion α. Here, the end portion 42a is not in contact with the pressing surface X ₂ of the flange portion β, as shown in FIG.
In this way, the sleeve 41a is coupled to the curved portion 42 of the elastic body 40. The sleeve 41a is fitted onto and fixed to the inner peripheral surface of the vibration ring main body 31. That is, an end 42a on the outer diameter side of the curved portion 42 is connected to the vibration ring main body 31 via the sleeve 41a.

The same applies to the sleeve 41b. As shown in FIGS. 3 and 4, the sleeve 41b includes a cylindrical portion δ that constitutes an inner cylindrical surface Y ₁ parallel to the axis, and a flange portion ε that protrudes toward the inner circumferential side from one end of the cylindrical portion δ. It has Here, it is preferable that the flange portion ε has a guide portion ζ. Although the flange portion ε is connected to the cylinder portion δ at one end, it is preferable that the other end of the flange portion ε is connected to the guide portion ζ. As shown in FIGS. 3 and 4, the guide portion ζ preferably extends in a direction parallel to the axial direction.
When the flange portion ε has the guide portion ζ, positioning of the jig becomes easier during the manufacturing process, contributing to improvement in work efficiency during the manufacturing process.

The end 42b of the curved portion 42 of the elastic body 40 on the inner diameter side is fixed only to the inner cylindrical surface _Y1 parallel to the axis of the cylindrical portion δ. Here, the end portion 42b is not in contact with the pressing surface _Y2 of the flange portion ε, as shown in FIG.
In this way, the sleeve 41b is coupled to the curved portion 42 of the elastic body 40. The sleeve 41b is fitted onto and fixed to the outer peripheral surface of the hub 20. That is, the outer diameter side end 42b of the curved portion 42 is connected to the hub 20 via the sleeve 41b.

Note that the curved portion 42 can be fixed to the sleeve 41 (41a, 41b) by, for example, welding, vulcanization adhesion, or adhesion using an adhesive.

Therefore, the curved portion 42 connects the hub 20 and the vibration ring 30 in a fixed state, and can be elastically deformed when the vibration ring 30 is displaced in the torsional direction X with respect to the hub 20.

According to the dynamic damper 10 having the above configuration, the elastic body 40 and the vibration ring 30 resonate in a phase opposite to the phase of the displacement in the torsional direction X due to the vibration of the propeller shaft, so that it is possible to reduce the vibration of the propeller shaft. can.

When the vibration ring 30 of the dynamic damper 10 is displaced in the torsional direction X with respect to the hub 20 due to vibrations caused by the rotation of the propeller shaft, the curved portion 42 of the elastic body 40 is pulled in the torsional direction X. At this time, the rubber lump 43 formed on the curved part 42 increases the rigidity of the elastic body 40, and the outer diameter side and inner diameter side of the elastic body 40 are elastically deformed in a well-balanced manner centering on the rubber lump 43, so that the elastic body 40 This prevents stress from being concentrated in one part. As a result, the durability of the elastic body 40 can be improved.

According to the dynamic damper 10 of the embodiment shown in FIGS. 1 to 4, when the vibration ring 30 is displaced in the torsional direction X with respect to the hub 20, the curved portion 42 having a curved shape is pulled in the torsional direction X. . At this time, the radial length of the elastic body 40 increases due to the curved shape of the curved portion 42, and the allowable displacement amount of the elastic body 40 increases. As a result, the torsion durability against relative displacement of the vibration ring 30 is improved, and the range of vibration reduction effect against the rotation of the propeller shaft can be increased without increasing the space occupied by the elastic body 40 in the radial direction.

When the vibration ring 30 is twisted beyond a certain level as the rotational speed of the propeller shaft increases, the gap C1 between the protrusion 44 and the convex part 32 is reduced by pulling the curved part 42. The protrusion 44 contacts the protrusion 32 . When the projection 44 comes into contact with the projection 32, the amount of attenuation of vibration in the torsional direction X is increased. At this time, the protrusion 44 functions as a stopper, and can prevent the vibration ring 30 from being twisted beyond a certain level.

Next, the manufacturing method of the present invention will be explained.
The dynamic damper of the present invention can be obtained by the manufacturing method of the present invention.
The manufacturing method of the present invention includes a fixing step, a first press-fitting step, a second press-fitting step, and a third press-fitting step, which will be described below.

<Fixing process>
The fixing step included in the manufacturing method of the present invention will be explained.
In the fixing step, first, the elastic body 40, the sleeve 41a on the outer diameter side, and the sleeve 41b on the inner diameter side are prepared as shown in FIGS. 1 and 4.

The elastic body 40 can be manufactured using, for example, a conventionally known material and a conventionally known method. For example, materials include rubber-like elastic materials such as natural rubber (NR), ethylene propylene diene rubber (EPDM), butyl rubber, fluororubber, nitrile rubber, and chloroprene, and thermoplastic elastomers such as polyester elastomers and thermoplastic polyurethane. It can be selected and used as appropriate depending on the purpose. The elastic body 40 can be molded by pouring such a material into a mold.

The sleeve 41a on the outer diameter side and the sleeve 41b on the inner diameter side can be similarly obtained by a conventionally known method using, for example, a conventionally known material. For example, the sleeve 41a and the sleeve 41b can be obtained by pressing a plate-shaped metal (preferably a cold-rolled steel plate).

The end portion 42a of the curved portion 42 of the elastic body 40 is fixed only to the inner cylindrical surface _X1 of the sleeve 41a disposed on the outer diameter side. In other words, even a part of the end portion 42a should not come into contact with the pressing surface _X2 . Here, as in the embodiment described in Patent Document ₁ , if the end portion 42a of the curved portion 42 is present on the pressing surface When fitting the hub and vibration ring to the elastic body, the end 42a of the curved part 42 will be caught between the jig and the pressing surface _X2 , so the end a of the curved part 42 will be damaged. Put it away.
Further, the end portion 42b of the curved portion 42 of the elastic body 40 is fixed only to the inner cylindrical surface _Y1 of the sleeve 41b disposed on the inner diameter side. In other words, even a part of the end portion 42b should not come into contact with the pressing surface _Y2 . Here, as in the embodiment described in Patent Document _{1, if the end portion 42b of the curved portion 42 is present on the pressing surface X 2 ,} in the third press-fitting step to be described later, the pressing surface When pressing _Y2 from above using a jig, the end 42b of the curved part 42 will be caught between the jig and the pressing surface _X2 , so the end b of the curved part 42 will be damaged. Put it away.

In this way, the end 42a of the curved portion 42 of the elastic body 40 is fixed only to the inner cylindrical surface _X1 of the sleeve 41a disposed on the outer diameter side, and the end 42b of the curved portion 42 of the elastic body 40 is By fixing only to the inner cylindrical surface _Y1 of the sleeve 41b disposed on the inner diameter side, it is possible to fit the hub and the vibration ring to the elastic body with a sleeve disposed on the jig in the second press-fitting process described later. In addition, by pressing the pressing surfaces X ₂ and Y ₂ of the elastic body with a sleeve from above using a jig in the third press-fitting step, which will be described later, without damaging the end of the curved portion 42, the hub 20 and vibrations can be avoided. Even if it is press-fitted between the ring body 32 and the ring body 32, the end portion of the curved portion 42 is not damaged.
If the end of the curved portion 42 is damaged, the elastic body 40 will not be able to exhibit its desired performance, and as a result, the torsional load on the elastic body 40 will not be able to be reduced. It also becomes difficult to perform the stopper function.

The sleeves 41a, 41b and the ends 42a, 42b of the curved portion 42 can be fixed by, for example, welding, crosslinking, or bonding using an adhesive.
In this way, a sleeved elastic body 50 as shown in FIG. 4 can be obtained.

<First press-fitting process>
The first press-fitting step included in the manufacturing method of the present invention will be explained using FIGS. 5 and 6.
FIG. 5 is a schematic perspective view showing a preferred example of a jig used in the first press-fitting process, and FIG. 6 is a schematic partial sectional view for explaining the first press-fitting process.

In the first press-fitting step, the sleeved elastic body 50 obtained in the above-described fixing step is placed on a jig 60, as shown in FIG. That is, the sleeved elastic body 50 is arranged on the jig 60 so that the inner ring 62 supports the inner sleeve 41b from below, and the outer ring 64 supports the outer sleeve 41a from below.
The jig 60 is used by being placed, for example, on a table so that the bottom portion 66 is horizontal.

As shown in FIG. 5, the jig 60 has two rings (62, 64) arranged concentrically and fixed to a plate-shaped bottom 66. Each ring (62, 64) is cylindrical and has the same width (height protruding from the bottom 66).
Further, the radial distance t between the two rings in the jig 60 is approximately equal to the distance between the inner cylindrical surface X ₁ of the sleeve 41a and the inner cylindrical surface Y ₁ of the sleeve 41b.
Further, the width of the inner ring 62 itself is preferably larger than the width of the cylindrical portion δ of the sleeve 41b, and preferably smaller than the radial length of the pressing surface Y ₂ of the flange portion ε.
Further, the width of the outer ring 64 itself is preferably larger than the width of the cylindrical portion α of the sleeve 41a, and preferably smaller than the radial length of the pressing surface X ₂ of the flange portion β.
In such a case, the jig 60 can support at least part of the stress applied to the cylindrical parts α, δ of the sleeved elastic body 50 from below via the flange parts β, ε.

Here, if the flange portions β, ε have the guide portions γ, ζ, positioning with respect to the jig 60 becomes easy during the manufacturing process, contributing to improvement of work efficiency during the manufacturing process.

The jig 60 can be obtained, for example, using a conventionally known material and by a conventionally known method. For example, it can be obtained by cutting metal (preferably SS400 etc.).

As shown in FIG. 6, on such a jig 60, the sleeved elastic body 50 is arranged with the flange portions β and ε facing downward so that the inner cylinder surfaces X ₁ and Y ₁ are in the vertical direction. do.

<Second press-fitting process>
The second press-fitting step included in the manufacturing method of the present invention will be explained using FIG. 7.
FIG. 7 is a schematic partial cross-sectional view for explaining the second press-fitting step.

By the above-described first press-fitting process, the hub 20 is fitted from above into the inner sleeve 41b of the sleeved elastic body 50 disposed on the jig 60, and the outer sleeve 41a of the sleeved elastic body 50 is fitted from above. The vibration ring 30 is fitted from above.
Here, after the vibration ring 30 is fitted, the hub 20 may be fitted.

Further, it is preferable to fit the dry bearing 33 into the vibrating ring 30 and then into the sleeved elastic body 50.

The method of fitting the hub 20 and the vibration ring 30 into the sleeved elastic body 50 is not particularly limited. By applying stress to the hub 20 or the vibration ring 30 from above, these can be fitted into the sleeved elastic body 50.

<Third press-fitting process>
The first press-fitting step included in the manufacturing method of the present invention will be explained using FIGS. 8 and 9.
FIG. 8 is a schematic perspective view showing a preferred example of a jig used in the third press-fitting process, and FIG. 9 is a schematic partial sectional view for explaining the third press-fitting process.

In the third press-fitting step, another sleeved elastic body 52 is press-fitted between the hub 20 and the vibration ring main body 32 from above.

In the third press-fitting process, as shown in FIGS. 8 and 9, a jig 70 is used that can apply stress to the cylindrical parts α and δ via the flange parts β and ε of the sleeved elastic body 52.
The jig 70 is similar to the jig 60 described above, and only the height of the two rings (72, 74) can be increased. I will explain in detail.

As shown in FIG. 8, the jig 70 has two rings (72, 74) arranged concentrically and fixed to a plate-shaped bottom 76. Each ring (72, 74) is cylindrical and has the same width (height protruding from the bottom 76).
Further, the radial distance t between the two rings in the jig 70 is approximately equal to the distance between the inner cylindrical surface X ₁ of the sleeve 41a and the inner cylindrical surface Y ₁ of the sleeve 41b.
Further, the width of the inner ring 72 itself is preferably larger than the width of the cylindrical portion δ of the sleeve 41b, and preferably smaller than the radial length of the pressing surface Y ₂ of the flange portion ε.
Further, the width of the outer ring 74 itself is preferably larger than the width of the cylindrical portion α of the sleeve 41a, and preferably smaller than the radial length of the pressing surface X ₂ of the flange portion β.
In such a case, stress can be applied to the cylindrical portions α and δ of the other sleeved elastic body 52, so that deformation of the sleeve can be suppressed. If the stress from the jig 70 is not easily applied to the cylindrical parts α and δ, there is a possibility that the flange parts β and ε will be deformed.

Here, if the flange portions β, ε have the guide portions γ, ζ, positioning with respect to the jig 60 becomes easy during the manufacturing process, contributing to improvement of work efficiency during the manufacturing process.

The jig 70 is used while being fixed so that the bottom portion 76 is horizontal.

The jig 70 can be obtained, for example, using a conventionally known material and by a conventionally known method. For example, it can be obtained by cutting metal (preferably SS400 etc.).

Using such a jig 70, the hub 20 and the vibration ring main body 31 are connected from above to another sleeved elastic body 52 with its inner cylindrical surfaces X ₁ and Y ₁ parallel to the vertical direction. Press fit between. Here, with the flanges β and ε facing upward, the pressing surfaces X ₂ and Y ₂ are pressed together using the jig 70 to fit together.

The dynamic damper of the present invention can be obtained by such a manufacturing method of the present invention.

10 Dynamic damper 20 Hub 21 Outer surface 30 Vibration ring 31 Vibration ring body 32 Convex portion 33 Dry bearing 40 Elastic body 41 Sleeve 42 Curved portion 43 Rubber mass 44 Projection 50, 52 Elastic body with sleeve 60, 70 Jig 62, 72 Inner ring 64 _, 74 Outer ring _{C1 Gap} X Torsion direction t Distance between inner ring and outer _ring ζ Guide part

Claims (3)

A hub, a vibration ring, a pair of elastic bodies, a bearing, and a pair of sleeves on the outer diameter side and the inner diameter side ,
The vibration ring is disposed on the outer peripheral side of the hub, and has an annular vibration ring main body and a convex portion protruding toward the outer peripheral surface of the hub on the inner peripheral side thereof,
The pair of elastic bodies are arranged to sandwich the convex portion of the vibration ring from both sides in the axial direction, connect the hub and the vibration ring main body via the sleeve, and curve outward in the axial direction. a curved portion; and a protrusion protruding from the inner surface of the curved portion toward the convex portion,
The bearing is a dynamic damper disposed between the convex portion and the hub,
Each of the pair of sleeves has a cylindrical shape, and has a cylindrical portion forming an inner cylindrical surface parallel to the axial direction and a flange portion , and the flange portion of the sleeve on the outer diameter side is located at one end of the cylindrical portion. The flange portion of the sleeve on the inner diameter side projects toward the inner circumference side from one end of the cylindrical portion, and the inner diameter side of the curved portion of the elastic body and A dynamic damper, wherein each of the ends on the outer diameter side is fixed only to the inner cylindrical surface of the sleeve on the inner diameter side and the outer diameter side . The dynamic damper according to claim 1, wherein the flange portion of the sleeve has a guide portion. a fixing step of obtaining a sleeved elastic body by fixing each of the ends of the curved portion of the elastic body only to the inner cylindrical surface of each of the two sleeves disposed on the inner diameter side and the outer diameter side;
The sleeved elastic body is placed on a jig that supports at least a portion of the stress applied to the cylindrical portion from below via the flange portion, and the inner cylindrical surface is in the vertical direction and the flange portion is on the lower side. a first press-fitting step of placing the
In the first press-fitting step, the hub is fitted from above into the sleeve on the inner circumference side of the sleeved elastic body disposed on the jig, and the hub is fitted from above into the sleeve on the outer circumference side of the sleeved elastic body. a second press-fitting step of fitting the vibration ring from the
Using a jig that can apply stress to the cylindrical part through the flange part, another elastic body with a sleeve is attached with the inner cylindrical surface facing vertically and with the flange part facing upward. , a third press-fitting step of press-fitting between the hub and the vibration ring main body from above;
A method for manufacturing a dynamic damper, comprising: obtaining the dynamic damper according to claim 1 or 2.

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