JPH0231622Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field) The present invention relates to a dual-type dynamic damper, and in particular, by being attached to a rotating shaft such as the crankshaft of an internal combustion engine, it reduces vibration and noise in the rotating shaft and engine. The present invention relates to a dual-type damper that effectively reduces the

(Prior Art) Generally, when a rotating shaft such as a crankshaft of an internal combustion engine rotates, complex torque fluctuations are induced in the rotating shaft, which causes extremely complex vibrations and vibrations in the rotating shaft and the engine. Noise is generated, and furthermore, problems such as breakage of the rotating shaft are caused.

Therefore, in the past, in vehicle engines, etc., in addition to attaching a flywheel to the rotating shaft to smooth the torque,
As shown in Utility Model Application Publication No. 56-115050, etc.
A cylindrical torsional damper having a sub-vibration system (vibration absorber) is attached to the rotating shaft, and the sub-vibration system resonates, thereby absorbing vibrations and noise in the main vibration system (rotating shaft). To try to reduce this, so-called dynamic vibration absorbers have been adopted.

By the way, in such a torsional damper, for example, a damper pulley including a boss portion fixed to a rotating shaft such as a crankshaft,
a cylindrical damper mass arranged radially outward and concentrically with respect to the damper pulley, and a cylindrical damper mass made of an elastic material such as rubber as a buffer between the damper pulley and the damper mass. The purpose of this structure is to reduce the vibration and noise of the engine by reducing the resonance amplitude of torsional vibration in the crankshaft, etc.

However, the vibrations generated in crankshafts, etc. are mainly a combination of two vibrations: torsion and bending (in the direction perpendicular to the axis), and exhibit various vibration modes depending on the supporting state of the rotating shaft and engine. Therefore, in the conventional vibration suppression mechanism using a torsional damper as described above,
The full effect could not be achieved.

In other words, in the case of a rotating shaft equipped with such a damper, the torsional vibration that occurs is caused by shear deformation in the elastic body acting as the buffer. The mass can effectively act as a damper (vibration absorber), but on the other hand, in response to the displacement of the mass corresponding to the bending vibration generated on the rotating shaft, the deformation of the elastic body is compressive or tensile. In addition, the elastic body is required to have a certain spring hardness in order to achieve the desired vibration damping effect against torsional vibration, and its thickness is regulated. However, the spring characteristics of such an elastic body in the direction perpendicular to the axis are set to be hard, and therefore the mass attached to it cannot effectively act as a damper against bending vibrations.

In short, torsional dampers, which serve as conventional vibration absorbers that are attached to a rotating shaft such as a crankshaft to absorb and reduce the vibrations of the rotating shaft, are capable of absorbing vibrations in the torsional direction of the rotating shaft. It is effective only for vibrations in the bending direction, and does not contribute to absorbing vibrations in the bending direction. Therefore, it is effective only for rotating shafts whose vibrations have two directions, the torsional direction and the bending direction, such as the crankshaft of an internal combustion engine. When used in a motor vehicle, it has not been possible to effectively reduce the vibration and noise of the rotating shaft and engine.

Therefore, with the aim of solving the above-mentioned problems with conventional torsional dampers, the applicant of the present application has previously proposed a dual Several types of dampers were proposed. For the dual damper proposed earlier, for example,
A first damper mass is provided via a first elastic body on the radially outer side of a cylindrical portion of a damper pulley having a boss portion fixed to a predetermined rotating shaft, and
A cylindrical second damper mass is disposed concentrically within the inner space of the cylindrical portion of the damper pulley, and a second damper mass is disposed between the axial end of the second damper mass and the damper pulley. The structure includes a second elastic body that exerts a shearing force against the axial movement of the damper mass.

In other words, in a dual type damper having such a structure, the first damper mass provided through the first elastic body with respect to the damper pulley rotates at a predetermined rotational speed at which the damper is to be attached. It functions as a sub-vibration system for torsional vibration generated on the shaft (main vibration system), and acts effectively as a dynamic vibration absorber against torsional vibration. Since it is attached via a second elastic body arranged in such a manner that deformation in response to displacement in the right angle direction generates a shearing force, the spring characteristics of the second elastic body in the direction perpendicular to the axis are sufficient. Therefore, the second damper mass effectively functions as a sub-vibration system for bending (in the direction perpendicular to the axis) generated on the rotation shaft to which such a damper pulley is attached, This means that it can effectively act as a vibration absorber.

Therefore, by attaching such a dual type damper to a rotating shaft such as a crankshaft of an internal combustion engine, vibrations generated in the rotating shaft can be suppressed very easily and effectively. The vibration and noise of such an engine can be significantly reduced.

(Problems) However, as a result of further consideration by the applicant of the above-mentioned dual-type damper, in such a dual-type damper,
In addition to the fact that the second damper mass is disposed within a relatively narrow space in the cylindrical portion of the damper pulley, when relatively large bending vibrations are input, Since the displacement of the second damper mass housed in the cylindrical part in the direction perpendicular to the axis becomes excessive, the outer circumferential surface of the second damper mass may hit the inner circumferential surface of the cylindrical part, and this causes abnormal noise. At the same time, it has been discovered that such impact may cause deformation or damage to the damper pulley or damper mass.Therefore, from the viewpoint of the performance and durability of such dampers, further improvements have been made. There was room.

(Solution Means) Here, the present invention was made against the background of the above-mentioned circumstances, and its feature is that by being attached to a predetermined rotating shaft, it is possible to connect the rotating shaft and the engine. vibration in,
In the above-mentioned dual type damper that reduces noise, (a) a boss portion attached to a rotating shaft, a cylindrical portion located radially outside of the boss portion, and a connection connecting the boss portion and the cylindrical portion; (b) a first damper mass disposed concentrically at a predetermined distance radially outward of the cylindrical portion of the damper pulley; and (c) a cylindrical portion of the damper pulley. and (d) a cylindrical second damper disposed concentrically within the inner space of the cylindrical portion of the damper pulley. Mass and (e)
(f) a second elastic body that supports the second damper mass at one end in the axial direction and exerts a shearing force against movement of the second damper mass in the radial direction; an elastic stopper member provided on the outer circumferential surface of the second damper mass or on the inner circumferential surface of the cylindrical part of the damper pulley opposite to the outer circumferential surface, and protruding from the outer circumferential surface or the inner circumferential surface at a predetermined height; It consists in being configured to include.

(Effect of the invention) That is, in the dual type damper having the structure according to the invention, the first damper mass and the second damper mass are respectively generated at the predetermined rotating shaft to which the damper is attached. It functions effectively as an auxiliary vibration system for the torsional vibration and bending vibration caused by the rotary shaft, and thereby the vibration generated in the rotating shaft can be extremely effectively suppressed, and the vibration and noise of the engine can be significantly reduced. Even if excessive vibration in the direction perpendicular to the axis is input to the damper and an excessive displacement is caused in the second damper mass, the outer circumferential surface of the second damper mass or the outer circumferential surface The elastic stopper provided on the inner circumferential surface of the cylindrical portion of the damper pulley facing the damper pulley can buffer the impact against the inner circumferential surface of the cylindrical portion of the damper pulley, thereby further improving the performance and durability of the dual-type damper. It can be improved.

(Example) Hereinafter, in order to clarify the present invention more specifically, one example according to the present invention will be described in detail based on the drawings.

First, FIG. 1 shows a longitudinal cross-sectional view of a dual-type damper 8 that can also be used for multiple V-pulleys and has a structure according to the present invention.

In this figure, 10 is attached to a predetermined rotating shaft such as the crankshaft of an internal combustion engine,
It is a steel damper pulley that rotates together with it, and is attached to a predetermined rotating shaft.
A small-diameter cylindrical boss portion 14 having a keyway 12 as a power transmission portion on its inner circumference, and the boss portion 1
A cylindrical portion 16 is located concentrically at a predetermined distance on the outer side of the cylindrical portion 4, and a cylindrical portion 16 is arranged in the radial direction at one end of the boss portion 14, which connects the outer circumferential surface of the boss portion 14 and the inner circumferential surface of the cylindrical portion 16. The connecting portion 18 extends outward in the form of a flange. Note that the connecting portion 18 on the inner circumferential surface of the cylindrical portion 16
is formed at the boss portion 1 in the axial direction.
The connecting portion 18 partitions the internal space of the cylindrical portion 16 in the direction perpendicular to the axis, and the internal space on the side where the boss portion 14 is not located is made relatively large. , mass accommodation space 2
0 is formed.

Further, a first damper mass 22 made of steel is arranged concentrically on the radially outer side of such a damper pulley 10. This first damper mass 2
2 has a substantially cylindrical shape having substantially the same length as the cylindrical portion 16 of the damper pulley 10, and has a large number of V grooves 24 formed on its outer peripheral surface. By winding a predetermined belt having a cross-sectional shape corresponding to those V grooves 24 around the outer peripheral surface, the dual type damper 8 transfers the driving force from the crankshaft to a predetermined subsequent member. It is configured so that it can function as a belt drive pulley for transmission.

A first elastic member 26 made of rubber is disposed between the first damper mass 22 and the cylindrical portion 16 of the damper pulley 10. As shown in FIG. 2, the first elastic member 26 has a length that is equal to the damper pulley 10, which is arranged concentrically with the first damper mass 22 at a predetermined distance apart from the first damper mass 22. It is vulcanized and molded integrally with a metal sleeve 28 having substantially the same thin-walled cylindrical shape, and the metal sleeve 2
8 is press-fitted and fixed to the outer peripheral surface of the cylindrical portion 16 of the damper pulley 10, thereby being integrally connected to the damper pulley 16.

On the other hand, the mass accommodation space 20 of the damper pulley 10
The second damper mass 30 disposed within the third
As shown in the figure, it has a cylindrical shape,
At one end in the axial direction, a second annular elastic member 34 with a predetermined thickness is attached to one end surface of an annular mounting bracket 32 having an outer diameter larger than the second damper mass 30 by a predetermined dimension. They are integrally attached so that they are located on the same axis. Note that the mounting bracket 32 has a plurality of through holes 36 that penetrate in the axial direction and are provided at equal intervals in the circumferential direction, and the second elastic member 34 is inserted into these through holes 36. Therefore, the second damper mass 3 due to the second elastic member 34
0 and the mounting bracket 32 are improved.

Further, as is clear from FIGS. 1 and 3, a groove 38 extending in the circumferential direction is formed on the outer circumferential surface of the second damper mass 30, and the second elastic member is formed in the axial direction. A ring-shaped ring is provided to be biased toward the side opposite to the side to which it is fixed, and has a convex portion of a predetermined height on the outer circumferential surface and a substantially rectangular cross section with respect to the groove 38. Elasticity (rubber)
The stopper 40 is attached with its base fitted into the groove 38. As a result, an elastic convex portion having a predetermined height and extending in the circumferential direction is formed on the outer circumferential surface of the second damper mass 30.

As shown in FIG.
The second damper mass 30 is fixed to the damper pulley 10 by being press-fitted into the mass accommodating space 20 on the inner circumferential surface of the opening end of the second damper mass 30 . A damper mass 30 is concentrically attached to and supported by the damper pulley 10 via a second elastic member 34.

Note that the outer diameter of the second damper mass 30 is smaller than the inner diameter of the cylindrical portion 16 of the damper pulley 10 by a predetermined dimension, so that the second damper mass 30 is attached to the damper pulley 10. Under the condition, the second elastic member 34
The structure allows for a predetermined amount of displacement in the direction perpendicular to the axis due to deformation.

The dual type damper 8 having such a structure is used by being attached to a predetermined rotating shaft such as a crankshaft of an internal combustion engine on the inner circumferential surface of the boss portion 14 thereof.

Therefore, in the dual type damper 8 having such a structure, deformation in the first elastic member 26 occurs due to shearing in response to vibrations in the torsional direction generated on the rotating shaft to which the damper pulley 10 is attached. The first damper mass 22 attached to it acts as a vibration absorber (sub-vibration system) for such vibrations.
This means that it can work effectively as a
On the other hand, in response to vibrations in the bending direction (direction perpendicular to the axis) generated in the rotating shaft, deformation in the second elastic member 34 is caused by shearing, and therefore, the second elastic member 34 attached to it The damper mass 30 can effectively act as a vibration absorber (sub-vibration system) against such vibrations.
That is, by installing the dual type damper 8 in this embodiment, the vibrations generated in the rotating shaft can be absorbed and suppressed very effectively, thereby significantly reducing the vibration and noise of the engine. You get it.

And also, such dual type damper 8
Since the second damper mass 30 has an elastic stopper 40 extending in the circumferential direction on its outer peripheral surface, temporary excessive vibrations are input to the damper 8 due to engine vibrations. Therefore, even if an excessive displacement is caused to the second damper mass 30, the second damper mass 3 relative to the cylindrical portion 16 of the damper pulley 10
The impact caused by the impact on the elastic stopper 4
0, the occurrence of abnormal noise due to such hitting can be well prevented, and
Deformation and damage to the cylindrical portion 16 and the second damper mass 30 can be effectively prevented, and their performance and durability can be further improved.

Note that in this embodiment, the second damper mass 30 is located in the mass accommodation space 2 of the damper pulley 10.
0, the connecting portion 1 of the damper pulley 10
8 and the mounting bracket 32 press-fitted into the inner circumferential surface of the cylindrical portion 16. In the event that the second elastic member 34 is damaged, Even if this happens, the mounting fittings 32 function as a fail-safe mechanism, and the second damper mass 30 can be effectively prevented from falling off (jumping out), and its safety can be ensured.

Next, FIG. 4 shows a dual-type damper 48 as another embodiment having a structure according to the present invention.

In the following drawings, members having the same structure as those in the embodiment described above are designated by the same numbers as the corresponding members, and detailed explanation thereof will be omitted.

That is, as shown in FIG. 4, the dual type damper 48 in this embodiment is disposed within the mass accommodation space 20 of the damper pulley 10 having the same structure as in the previous embodiment.
Second damper mass 3 with elastic stopper 40
0, a mounting bracket 42 is integrally attached to the second damper mass 30 via a second elastic member 34, and is formed as an annular member having substantially the same cross-sectional shape as the second damper mass 30. The metal fittings 42 are
It is integrally formed by being fixed to the connecting portion 18 of the damper pulley 10 with a plurality of mounting bolts 46 inserted through a plurality of through holes 44 formed in the connecting portion 18 of the damper pulley 10. It is said to be a structure.

In the dual type damper 48 having such a structure, the effect of providing the first and second damper masses as described above and the elastic stopper 40 on the outer peripheral surface of the second damper mass 30 are as follows.
In addition to being able to achieve good effects due to the provision of the second sub-vibration system, even if the second sub-vibration system is damaged, it is possible to easily replace only the second sub-vibration system. Thereby, the substantial lifespan of such a damper can be effectively improved.

Further, FIG. 5 shows a dual-type damper 50 as another embodiment of the present invention.

As is clear from this figure, the dual type damper 50 in this embodiment has a different structure compared to the damper pulley 10 which has the same structure as the dual type damper 8 shown in the previous embodiment.
A second damper mass 5 provided with an elastic stopper 40 on its outer periphery, disposed within the mass accommodation space 20.
2 is connected to the connecting portion 1 via the second elastic member 54 at the end of the damper pulley 10 on the connecting portion 18 side.
It has a structure in which it is integrally attached to 8. In addition, in the figure, 56 is a drop-off prevention pin, and an insertion hole 58 is provided to penetrate the wall of the second damper mass 52 and the second elastic member 54 in the axial direction.
is inserted through it with a predetermined gap,
The tip part is screwed into the connecting part 18, and even if the second sub-vibration system is damaged, the head part 60 has a structure that can prevent the second damper mass 52 from popping out. has been done.

Dual type damper 50 in this embodiment
In this case, as described above, the effect of providing the first and second damper masses and the effect of providing the elastic stopper 40 on the outer peripheral surface of the second damper mass 52 can be favorably achieved. In addition, since the second damper mass 52 is directly attached to the damper pulley 10, there is no need to provide a mounting bracket.
Its structure can be simplified.

Furthermore, FIG. 6 shows a dual-type damper 62 as yet another embodiment of the present invention.

Dual type damper 62 in this embodiment
, the leg portion 66 is screwed onto the end of a predetermined rotating shaft 64 of a crankshaft or the like to which the damper 62 is attached and fixed, and the flange portion 68 connects the boss portion 14 of the damper pulley 10. A set bolt 7 that presses and fixes the rotating shaft.
A substantially hat-shaped mounting bracket 76 having a circular recess 74 in the center is fixed to the axial end surface of the head portion 72 of 0 with a mounting bolt 78 so as to cover the opening of the mass storage space 20. A second damper mass 80 equipped with an elastic stopper 40 disposed within the mass housing space 20 is attached to the inner surface of the mounting fitting 76 via a second elastic member 82. It is a structure that is attached and supported. In the figure, reference numeral 84 indicates a plurality of ventilation holes that are provided through the mounting bracket 76 in the axial direction, to prevent heat build-up in the mass accommodation space 20, and to prevent deterioration of damper performance and durability due to heat. The structure is said to be able to effectively prevent problems such as deterioration.

Even in the dual type damper 62 having such a structure, the effect of providing the first and second damper masses as described above and the elastic stopper 4 on the outer peripheral surface of the second damper mass 80 can be obtained.
0, and even if the second elastic member 82 supporting the second damper mass 80 were to break, the second damper The mass 80 can be completely prevented from popping out from inside the mass accommodation space 20 by the mounting bracket 76, and its safety can be ensured. The second sub-vibration system, which is integrally formed by vulcanization bonding with the elastic member 82, is attached to the rotating shaft 64 using bolts.
The manufacturability of such a sub-vibration system and the assemblability of the damper mechanism can be extremely improved.

Although several embodiments having structures according to the present invention have been described in detail above, these are literal illustrations, and the present invention should be construed as being limited only to the specific examples of such illustrations. isn't it.

For example, in the damper shown in the above embodiment, the elastic stopper 40 provided on the outer peripheral surface of the second damper mass has its base formed in a concave groove extending in the circumferential direction provided in the second damper mass. 38, the elastic stopper is designed to buffer the impact at least at the portion where the second damper mass hits the cylindrical portion 16 when the second damper mass is excessively displaced. The second damper mass 86 may be provided with a concave groove as long as it protrudes from the outer peripheral surface of the second damper mass at a predetermined height, as shown in FIG. It is also possible to form the elastic stopper 88 having a rectangular cross section of a predetermined height by adhering it to the outer peripheral surface thereof.

Further, the damper pulley 10 can be operated without providing such an elastic stopper in the second damper mass.
On the inner circumferential surface of the cylindrical portion 16, at least the second damper mass may be provided at a portion where it strikes, and even if such a structure is used, the present invention as described above may not be possible. The effects of this can be well expressed.

Furthermore, although the dual type damper in the above embodiment was formed to double as a multiple V-pulley, it could also be constructed so that it could function only as a vibration absorber on the rotating shaft to which it is attached, without forming such a V-groove. , can be easily formed and used.

Although not listed in detail, the present invention may be implemented with various changes, modifications, improvements, etc. based on the knowledge of those skilled in the art, and such embodiments may be implemented in accordance with the present invention. It goes without saying that any of these are included within the scope of the present invention as long as they do not depart from the spirit of the invention.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a dual-type damper that is an embodiment of the present invention, and FIG. 2 shows a first damper mass, a first elastic member, and the like used in the embodiment shown in FIG. FIG. 3 is a longitudinal cross-sectional view showing an integrally vulcanized product of a metal sleeve, and FIG. 3 is an integrally vulcanized product of the second damper mass, second elastic member, and mounting fitting used in the embodiment shown in FIG. 1; It is a partially cutaway sectional view showing the product.
Further, FIGS. 4 to 6 are longitudinal cross-sectional explanatory views showing other embodiments of the dual type damper according to the present invention, and FIG. FIG. 6 is a partially cross-sectional explanatory view showing another example of the state in which the elastic stopper is attached to the damper mass of FIG. 8, 48, 50, 62: Dual type damper, 10: Damper pulley, 14: Boss part, 1
6: Cylindrical part, 18: Connection part, 20: Mass accommodation space, 22: First damper mass, 26: First elastic member, 30, 52, 80, 86: Second damper mass, 34, 54, 82: second elastic member, 4
0,88: Elastic stopper, 64: Rotating shaft.

Claims (1)

[Claims for Utility Model Registration] A damper pulley having a boss portion attached to a rotating shaft, a cylindrical portion located radially outward of the boss portion, and a connecting portion connecting the boss portion and the cylindrical portion; a first damper mass disposed concentrically at a predetermined distance on the radially outer side of the cylindrical portion of the damper pulley; and interposed between the cylindrical portion of the damper pulley and the first damper mass. a cylindrical second damper mass disposed concentrically within the inner space of the cylindrical portion of the damper pulley; a second elastic body supported at an end and exerting a shearing force against the radial movement of the second damper mass; and an outer circumferential surface of the second damper mass or the damper facing the outer circumferential surface. an elastic stopper member provided on the inner circumferential surface of the cylindrical portion of the pulley and protruding from the outer circumferential surface or the inner circumferential surface at a predetermined height;
A dual type damper characterized by including.