JPH0314594Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a structure of a damper pulley that reduces torsional vibration and bending vibration generated in the crankshaft of an engine.

[Prior Art] Conventionally, in order to reduce noise caused by torsional vibration of the crankshaft, a damper pulley has been developed in which a pulley hub is provided at the front end of the crankshaft, and a damper mass for torsional vibration is connected to the outer periphery of the pulley hub via damper rubber. Are known.

In conventional engines, the crankshaft was heavy and extremely rigid, so the bending vibrations generated in the crankshaft were not so large. Therefore, consideration of bending vibration has not been given much importance in damper pulleys as well.

However, in recent years, as crankshafts have become lighter and engine horsepower has increased, the bending vibrations generated in the crankshafts have also increased, which has had a negative impact on suppressing vehicle body vibrations and noise. Furthermore, as bending vibrations increase, problems have arisen that cannot be ignored in terms of the strength of the crankshaft itself, and there has been a strong demand for a dynamic damper that can withstand bending vibrations.

Therefore, the present applicant has previously proposed a crank damper pulley structure that can reduce both torsional vibration and bending vibration generated in the crankshaft (Japanese Patent Laid-Open No. 61-211552).

FIG. 2 shows the structure of the damper pulley disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 61-211552. In the figure, 1 indicates a crankshaft, and 2 indicates a pulley hub. pulley hub 2
is fitted into the end of the crankshaft 1 and fastened with a set bolt 3. A torsional vibration damper mass 4 having a belt groove is disposed on the outer periphery of the pulley hub 2. The torsional vibration damper mass 4 is connected to the pulley hub 2 by a damper rubber 5 interposed between the damper mass 4 and the pulley hub 2. ing.

A cavity 6 opening in the axial direction is formed in the pulley hub 2, and a dish-shaped damper support 7 is press-fitted into the cavity 6. and damper support 7
, a damper mass 8 for bending vibration and a damper rubber 9 are overlapped in the axial direction, and the damper mass 9 for bending vibration is connected to a damper support 7 via the damper rubber 9.
is connected to.

[Problems to be solved by the invention] The above-described structure of the crank damper pulley guarantees the strength of the crankshaft and exhibits excellent effects in suppressing engine vibration and noise, but it complicates the manufacturing process. It has a drawback. That is, in the manufacturing process of this crank damper pulley, two parts are used to connect the damper mass for torsional vibration and the pulley hub, and the damper mass for bending vibration and the damper support via damper rubber (vulcanization bonding).
Two vulcanization steps are required. Furthermore, a press-fitting process for press-fitting the damper support into the pulley hub is also required.

Therefore, there is a problem that the manufacturing process becomes complicated and the manufacturing cost of the damper pulley increases.

The purpose of this invention is to provide a crank damper pulley structure that can reduce the number of parts in the damper pulley, simplify the manufacturing process, and reduce costs while maintaining the damping function of torsional and bending vibrations of the crankshaft. shall be.

[Means for Solving the Problems] The vehicle crank damper pulley structure of the present invention that meets this objective has a damper mass for torsional vibration and a damper mass for bending vibration attached to a pulley hub attached to the end of the crankshaft using damper rubber. A crank damper pulley structure connected via
The torsional vibration damper mass is disposed on the outer periphery of the pulley hub, and the bending vibration damper mass is disposed on the axial end face side of the pulley hub, and the damper rubber is connected to a cylindrical portion extending in the circumferential direction along the outer circumferential surface of the pulley hub. Consisting of a side portion protruding radially inward from the cylindrical portion along the axial end of the pulley hub, and the cylindrical portion and the side portion are integrally formed,
The damper mass for torsional vibration is connected to a pulley hub via the cylindrical portion of the damper rubber, and the damper mass for bending vibration is connected to the pulley hub via the side portion of the damper rubber.

[Function] In the crank damper pulley of a vehicle configured in this way, the damper mass for torsional vibration is connected to the outer periphery of the pulley hub via the cylindrical part of the damper rubber, and the damper mass for bending vibration is connected to the side part of the damper rubber. Since it is directly connected to the axial end face side of the pulley hub through the damper support, there is no need for a damper support that requires a press-fitting process as in the past.

In addition, the damper rubber is not divided into parts for each damper mass, but is formed integrally.
In the manufacturing process, damper rubber serving as a connecting member can be filled at once between the torsional vibration damper mass, the bending vibration damper mass, and the pulley hub. The torsional vibration damper mass and the bending vibration damper mass are connected to the pulley hub by vulcanization and adhesion of the filled damper rubber.

Therefore, the press-fitting process is eliminated and only one vulcanization process is required, which simplifies the manufacturing process and reduces costs.

[Embodiments] Hereinafter, preferred embodiments of the crank damper pulley structure for a vehicle according to the present invention will be described with reference to the drawings.

FIG. 1 shows a crank damper pulley structure for a vehicle according to an embodiment of the present invention. In the figure, 11
indicates a crankshaft, and 12 indicates a pulley hub. The pulley hub 12 has a boss portion 1
2a and a hub portion 12b, which are integrally formed. The boss portion 12a is provided at the center of the pulley hub 12, and has a hole 13 formed in the center.The end of the crankshaft 11 is fitted into the hole 13. is provided with a keyway 14 for fastening. A cylindrical hub portion 12b is located outside the boss portion 12a, and the hub portion 12b is concentric with the boss portion 12a. One end surface 12c of the hub portion 12b
is a thick part, and the end part 12c is the boss part 12.
It protrudes forward from the end face on the set bolt 15 side of a. The other end surface 12d of the hub portion 12b is
It is located approximately in the middle of the boss portion 12a in the axial direction. The pulley hub 12 is fastened to the crankshaft 11 by a set bolt that is screwed into the shaft end of the crankshaft 11.

A torsional vibration damper mass 16 is arranged on the outer periphery of the pulley hub 12, and the axial length of this torsional vibration damper mass 16 is longer than the pulley hub 1.
The length of the hub portion 12b is longer than that of the second hub portion 12b.
A plurality of belt grooves 17, 18, and 19 are formed on the outer peripheral surface of the torsional vibration damper mass 16.

A bending vibration damper mass 20 is disposed on the end face 12c side of the pulley hub 12 in the axial direction, that is, on the end face on the thick wall side. Damper mass 2 for bending vibration
0 has a ring shape with a rectangular cross section. The outer periphery of the damper mass 20 for bending vibration is the inner peripheral surface 16a of the damper mass 16 for torsional vibration.
A gap 21 is formed between the outer peripheral surface 20a of the damper mass 20 for bending vibration and the inner peripheral surface 16a of the damper mass 16 for torsional vibration.

Pulley hub 12 and damper mass 16 for torsional vibration
A damper rubber 22 is interposed between the damper mass 20 and the damper mass 20 for bending vibration. Damper rubber 22
consists of a cylindrical portion 22a extending circumferentially along the outer peripheral surface 12e of the pulley hub 12, and a side portion 22b protruding radially inward from the cylindrical portion 22a along the axial end surface 12c of the pulley hub 12. There is. That is, the damper rubber 22 is formed into an annular shape with a substantially L-shaped cross section. The damper mass 16 for torsional vibration is connected to the pulley hub 12 via the cylindrical portion 22a of the damper rubber 22, and the damper mass 20 for bending vibration is connected to the damper rubber 22.
The pulley hub 12 is connected to the pulley hub 12 via the second side portion 22b.

Next, the operation of the crank damper pulley structure of the above-mentioned vehicle will be explained.

Torsional vibrations generated in the crankshaft 11 during engine operation are caused by the cylindrical portion 22 of the damper rubber 22.
a and a torsional vibration damper mass 16, the bending vibration is suppressed by the side part 22b of the damper rubber 22.
and is suppressed by a dynamic damper constituted by a damper mass 20 for bending vibration. Therefore, noise due to torsional and bending vibrations of the crankshaft 11 is reduced.

The damper rubber 22 has a cylindrical portion 22a and a side portion 22b.
Since the damper rubber 22 can be integrally formed, it becomes possible to simultaneously fill the spaces between the pulley hub 12 and the torsional vibration damper mass 16 and the bending vibration damper mass 20 with the liquid damper rubber 22 during the manufacturing process. That is, the filled damper rubber 2
Damper mass 1 for torsional vibration is created by vulcanization adhesion of 2.
6 and the bending vibration damper mass 20 can be connected to the pulley hub 12 at the same time.

Therefore, only one vulcanization process is required to attach the damper mass to the pulley hub 12.

[Effects of the invention] As explained above, in the vehicle crank damper pulley structure of the invention, the damper mass for torsional vibration and the damper mass for bending vibration are connected to the pulley hub by one damper rubber. The press-fitting step and one vulcanization step in the conventional manufacturing process can be eliminated. As a result, the manufacturing process can be simplified and the manufacturing cost of the damper pulley can be reduced.

Furthermore, since the number of parts of the damper pulley is reduced, there is also the effect that material costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a crank damper pulley structure for a vehicle according to an embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of a conventional vehicle crank damper pulley structure.
It is. 11... Crankshaft, 12... Pulley hub, 16... Damper mass for torsional vibration, 20...
Damper mass for bending vibration, 22... Damper rubber, 2
2a... Cylindrical part of the damper rubber, 22b... Side part of the damper rubber.

Claims (1)

[Scope of utility model registration request] In a crank damper pulley structure in which a torsional vibration damper mass and a bending vibration damper mass are connected to a pulley hub attached to an end of the crankshaft via a damper rubber, the torsional vibration damper mass is disposed on the outer periphery of the pulley hub, and the A damper mass for bending vibration is disposed on the axial end face side of the pulley hub, and the damper rubber is connected to a cylindrical part extending in the circumferential direction along the outer peripheral surface of the pulley hub, and from the cylindrical part to the axial end of the pulley hub. The damper mass for torsional vibration is connected to the pulley hub via the cylindrical portion of the damper rubber, and the damper mass for bending vibration is connected to the pulley hub through the cylindrical portion of the damper rubber. A crank damper pulley structure for a vehicle, characterized in that it is connected to a pulley hub via a side part of damper rubber.