JP2002295588A - Torsional damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a torsional damper 10 which does not damage a seal member 14 to seal a shaft hole 31 when built into a shaft end. SOLUTION: An oil seal 14 is mounted to a hub 11 as the seal member to be slidably in close contact with an end face 32 of an opening part of the shaft hole 31. When the torsional damper 10 is built into the shaft end, there is no fear of damaging the seal body 142, and moreover, by this, the building-in work can be easily executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torsional device which is attached to a rotating shaft such as a crankshaft of an engine and has a dynamic vibration absorbing function in a torsional direction of the rotating shaft by a vibration system comprising a mass body and a rubber-like elastic material. About damper.

[0002]

2. Description of the Related Art A crankshaft of an engine of an automobile or the like generates torsional vibration (vibration in the direction of rotation) with rotation. At the shaft end of the shaft,
A torsional damper is attached.

FIG. 7 schematically shows a mounted state of a conventional torsion damper. That is, this kind of torsional damper 100 is basically a hub 101 attached to the shaft end of a crankshaft 200.
And an annular mass body 10 concentrically arranged on the outer peripheral side thereof
2 and a rubber-like elastic body 103 for elastically connecting the hub 101 and the mass body 102. Then, in a predetermined rotation speed range, the mass body 102 is input by input of torsional vibration from the crankshaft 200.
The vibration system including the rubber-like elastic body 103 resonates, and a vibration displacement due to the resonance occurs in a phase opposite to the input vibration, thereby exhibiting a dynamic vibration absorbing effect.

[0004] On the other hand, an oil seal 202 for keeping the circumference of the shaft airtight is attached to the opening of the shaft hole 201a in the front cover 201 and the like of the engine. The oil seal 202 has an inner peripheral seal lip 202 a that is formed by a boss 101 of the hub 101 of the torsion damper 100.
The sealing function is achieved by slidably coming into close contact with the outer peripheral surface of a.

[0005]

According to the above prior art, the torsion damper 100 and the oil seal 202 are provided.
And must be installed separately. And in this case,
After the oil seal 202 is attached to the opening of the shaft hole 201a, when the torsion damper 100 is assembled to the shaft end of the crankshaft 200, the center is accurately aligned.
If the installation work is not performed carefully, the oil seal 202
Seal lip 202a of the boss 101a of the hub 101
There was a risk of being damaged due to interference with the device.

The hub 1 of the torsion damper 100
When the oil seal 201 is made of, for example, cast iron or the like, in order to realize good sealing performance of the oil seal 202, the outer peripheral surface of the boss portion 101a of the hub 101, which is a sliding surface with the seal lip 202a, is polished or the like. Therefore, there is a problem that the boss 101a needs to be quenched in order to prevent abrasion due to sliding, thereby increasing the manufacturing cost of the torsional damper 100.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a technical problem thereof is that, when assembled into a shaft end, the sealing member for sealing the shaft hole is not damaged and the cost is low. An object of the present invention is to provide a torsional damper that can be manufactured.

[0008]

Means for Solving the Problems The technical problems described above are:
This can be effectively solved by the present invention. That is, the torsion damper according to the invention of claim 1 is a hub that is attached concentrically to a rotating shaft, an annular mass body that is arranged concentrically with the hub and that can be relatively displaced, And a seal member attached to the hub and slidably in close contact with the shaft hole or a surface near the shaft hole.

[0009]

FIG. 1 is a half sectional view showing a first embodiment of a torsional damper according to the present invention by cutting along a plane passing through an axis. In the following description,
The “front” is a direction in which the shaft end of the crankshaft 20 faces, that is, the left side in FIG.
Means the right side in FIG. 1, that is, the engine side.

A torsion damper 10 according to this embodiment has a hub 11 attached to the shaft end of a crankshaft 20 of an engine, and an annular ring disposed concentrically and relatively displaceably on the outer peripheral side of the hub 11. Mass body 12
An annular rubber-like elastic body 13 elastically connecting between the opposing peripheral surfaces of the hub 11 and the mass body 12, and an oil seal 14 as a seal member attached to the hub 11.

The hub 11 is made of a metal such as cast iron or steel.
The key 21 prevents relative rotation and the bolt 2
2 and the boss 11
1 and a rim portion 1 extending from the outer diameter end of the radial portion 112 to the front side.
13.

The mass body 12 is made of the same material as the hub 11, that is, a metal such as cast iron or steel, and transmits a rotational force to the auxiliary machine by winding a belt (not shown) around the outer peripheral surface. Poly-V groove 121 is formed.

The rubber-like elastic body 13 is formed into an annular shape by an elastomer material having excellent heat resistance, cold resistance and mechanical strength and generating little internal heat, and then the outer peripheral surface of the rim portion 113 of the hub 11 and the outer peripheral surface thereof. It is press-fitted from one side in the axial direction to the inner peripheral surface of the mass body 12 facing in the radial direction, and fitted with a required compression allowance. In addition, the inner peripheral surface of the rim portion 113 and the inner peripheral surface of the mass body 12 facing each other are radially oriented to prevent the hub 11, the mass body 12, and the rubber-like elastic body 13 from falling off due to sliding in the axial direction. It has a gently undulating shape.

The natural frequency of the vibration system constituted by the mass body 12 and the rubber-like elastic body 13 in the torsional direction is
Is set in a frequency range where the amplitude of the torsional vibration of the crankshaft is maximized by the circumferential inertial mass of the rubber-like elastic body 13 and the torsional shear spring constant of the rubber-like elastic body 13.

The boss portion 111 of the hub 11 extends cylindrically to the rear side, that is, the engine side, and
Consists of a metal ring 141 fitted on the outer peripheral surface of the boss 111 with an appropriate interference, and a seal body 142 integrally vulcanized and bonded to the outer peripheral portion thereof with an elastomer material. The seal body 142 has a seal lip 142b extending in a tapered shape from the base 141a bonded to the metal ring 141 to the rear side and the outer diameter side. The seal lip 142b is formed, for example, on the front cover 30 of the engine. The end face 32 of the extended opening of the shaft hole 31 is slidably contacted with the end face 32.

A torsional damper 1 having the above configuration
0 is rotated together with the crankshaft 20 when the engine is driven. Then, during the rotation of the crankshaft 20, the frequency of the torsional vibration input via the hub 11 becomes
When the amplitude of the crankshaft 20 reaches a frequency range where the amplitude is maximized, the vibration system constituted by the mass body 12 and the rubber-like elastic body 13 resonates in an opposite phase to the input vibration. Therefore, the peak of the torsional vibration of the crankshaft 20 can be effectively reduced.

The oil seal 14 mounted on the boss portion 111 of the hub 11 has a seal lip 142b in the seal body 142, and the end face of the extended opening of the shaft hole 31 in the front cover 30 as the crankshaft 20 rotates. By sliding in close contact with 32, intrusion of dust and the like from shaft hole 31 is blocked.

Since the oil seal 14 is mounted on the hub 11, by mounting the torsion damper 10 on the shaft end of the crankshaft 20, it is simultaneously installed between the hub 11 and the front cover 30 of the engine. . Therefore, it is not necessary to separately incorporate the oil seal 14.

Moreover, the seal lip 142b of the seal body 142 is
Since the seal lip 142a is in axial contact with the end face 32 of the first extended opening, the seal lip 142a is not damaged during mounting. Therefore, the work of incorporating the torsion damper 10 can be easily performed in an automobile assembly line or the like.

Further, since the outer peripheral surface of the boss portion 111 of the hub 11 does not serve as a sliding surface with the seal lip 142b of the oil seal 14, there is no need to perform precision finishing or hardening of the boss portion 111 by polishing or the like. Therefore, the manufacturing cost of the torsional damper 10 can be reduced.

FIGS. 2A to 2C show hubs 11 respectively.
FIG. 10 is a half sectional view showing another attachment form of the metal ring 141 of the oil seal 14 with respect to FIG. That is, FIG.
The metal ring 141 of the oil seal 14 is attached to the hub 11
2 is fitted to the outer peripheral surface of the boss portion 111 of FIG.
In (A), the metal ring 141 is connected to the radial portion 1 of the hub 11.
12 is fitted on the inner periphery of an annular projection 112a formed on the back surface of the hub 12, and the one shown in FIG. 2B is fitted on an annular recess 112b formed on the back surface of the radial portion 112 of the hub 11. In FIG. 2C, the rim portion 113 of the hub 11 is extended to the rear side of the radial portion 112, and a metal ring 141 is fitted on the inner periphery of the extended portion. In any case, the outer periphery of the metal ring 141 is formed into a shape suitable for press-fitting into the hub 11, and the base 142a of the seal body 142 is integrally joined to the flange 141a extending therefrom toward the inner periphery. I have.

Various cross-sectional shapes of the seal body 142 of the oil seal 14 are conceivable. FIG. 3 is a half-sectional view showing another embodiment in which the cross-sectional shape of the seal body 142 is different, that is, in the above-described FIGS. 1 and 2, the seal lip 142b is tapered to the rear side and the outer diameter side. In the embodiment shown in FIG. 3, the seal body 142 is configured such that the seal body 142 is provided with the base 1.
The end surface 32 of the extended opening of the shaft hole 31 in the front cover 30 extends in a tapered shape from the rear surface 42a to the rear side and the inner peripheral side.
Seal lip 142c slidably in contact with the first seal lip 142c
And a second seal lip 142d extending in a tapered shape from the base portion 142a to the front side and the outer peripheral side and slidably in contact with the inner peripheral surface 33 of the expansion opening. The other parts are configured in the same manner as in FIG.

FIG. 4 is a half sectional view showing another embodiment in which the cross-sectional shape of the seal body 142 is different, that is, the first case in which the seal body 142 extends from the base 142a to the rear side and the outer side in a tapered shape. It has a seal lip 142e and a second seal lip 142c tapering from the base 142a to the front side and the outer side, both of which are the inner peripheral surface 33 of the extended opening of the shaft hole 31 in the front cover 30.
And are slidably contacted. The other parts are configured in the same manner as in FIG.

Also, in the present invention, the hub 11 is formed of a press-formed product of a metal plate, the mass body 12 is formed of a press-formed product of a metal plate, or the rubber-like elastic body 13 is formed of the hub 11 and the mass body 12. The same method can be applied to those vulcanized and bonded between them. FIG. 5 shows, as an example,
FIG. 10 is a half sectional view showing another embodiment in which the structures of the hub 11 and the mass body 12 are different.

That is, in the embodiment shown in FIG.
Both the hub 11 and the mass body 12 are made of a press-formed product of a metal plate. The rubber-like elastic body 13 is
Of the mass body 12 is press-fitted between the rim portion 113 and the inner peripheral cylindrical portion 122 of the mass body 12. In order to prevent this, a retaining portion 123 extending to the inner peripheral side to reach the rear side of the outer peripheral portion of the hub 11 is formed. The metal ring 141 of the oil seal 14 is fitted to the outer peripheral surface of the boss 111 extending rearward on the inner peripheral portion of the hub 11 with an appropriate interference.

In the embodiment of FIG. 5, the oil seal 14 has the same structure as that of FIG. 1. For example, the seal body 142 is integrated with the boss 111 of the hub 11 made of a metal plate. May be joined. FIG. 6 is a half cross-sectional view showing one example, that is, the boss portion 111 of the hub 11.
A flange 11 bent to the outer diameter side at the rear end of
The base portion 142a of the seal body 142 made of an elastomer material is integrated with the flange portion 114 by vulcanization bonding or the like. Other parts are the same as those in FIG.

With such a structure, the oil seal 1
4 and the mounting of the oil seal 14 on the hub 11 are performed at the same time, and the portion corresponding to the metal ring 141 in FIGS. 1 to 5 is a flange 114 formed as a part of the hub 11. Therefore, the number of manufacturing steps and the number of parts can be reduced, and manufacturing can be performed at lower cost.

[0028]

According to the torsion damper according to the first aspect of the present invention, since the hub is provided with the seal member slidably in close contact with the shaft hole or a surface in the vicinity thereof, the torsion damper is mounted on the hub. There is no risk that the seal member will be damaged at the time of assembling at the end, and therefore, the assembling operation can be easily performed. Further, since a sliding surface with the seal member is not formed on the hub, there is no need to perform precision finishing or quenching on the hub, and the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a half sectional view showing a mounted state of a torsion damper according to a first embodiment of the present invention, cut along a plane passing through an axis.

FIG. 2 is a half cross-sectional view showing another attachment form of the metal ring of the oil seal to the hub in a torsion damper according to the present invention, cut along a plane passing through an axis.

FIG. 3 is a half sectional view of a mounted state showing another embodiment of the torsion damper according to the present invention in which a sectional shape of a seal body is different.

FIG. 4 is a half sectional view of a mounted state showing another embodiment of the torsion damper according to the present invention, in which a sectional shape of a seal body is different.

FIG. 5 is a half sectional view showing another embodiment of the torsion damper according to the present invention, in which the structures of the hub and the mass body are different.

FIG. 6 is a half sectional view showing another embodiment in which the seal body is integrally joined to the hub in the torsion damper according to the present invention.

FIG. 7 is a half sectional view of a mounted state, showing a torsion damper according to a conventional technique, cut along a plane passing through an axis.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 torsion damper 11 hub 111 boss portion 112 radial portion 113 rim portion 12 mass body 13 rubber-like elastic body 14 oil seal (seal member) 141 metal ring 142 seal body 20 crankshaft 30 front cover 31 shaft hole 32 end face

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shinya Omoto 1000 Ojihara, Saihaku-cho, Saihaku-gun, Tottori Prefecture FK term (reference) 3J006 AE19 AE23 CA01

Claims (1)

[Claims] 1. A hub (11) concentrically mounted on a rotating shaft; an annular mass (12) arranged concentrically and relatively displaceable with the hub (11); A rubber-like elastic body (13) for elastically connecting the mass body (12) to the mass body (12), and a seal attached to the hub (11) and slidably fitted to the shaft hole (31) or a surface in the vicinity thereof. Member (14)
And a torsional damper comprising: