JPH0539228Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a damper structure that suppresses torsional vibration and bending vibration of an output shaft of an engine, that is, a crankshaft.

(Prior Art and its Problems) Some engines are equipped with a torsional damper and a bending damper at the shaft end of a crankshaft, as shown in Japanese Utility Model Application No. 154360/1983. The torsional damper is generally a rubber damper, and the damper mass and the damper rubber are arranged in parallel in the radial direction of the crankshaft to reduce torsional vibration of the crankshaft. Further, in the bending damper, the damper mass and the damper rubber are arranged side by side in the axial direction of the crankshaft to reduce bending vibration of the crankshaft. That is, in this bending damper, the bending vibration mode of the crankshaft is changed by the damper mass vibrating in the axial direction or radial direction of the crankshaft. The energy absorption of the bending vibration of the crankshaft is achieved by the damper rubber for the bending damper expanding and contracting in the axial direction of the crankshaft or being deformed in the radial direction, thereby absorbing the energy of the bending vibration of the crankshaft. is converted into heat generated inside the damper rubber.

By the way, as described above, the bending damper is constructed by arranging the damper mass and the damper rubber in parallel in the axial direction of the crankshaft, and therefore tends to cause excessive vibration in the radial direction of the crankshaft. Of course, this excessive vibration in the radial direction forces the damper rubber to undergo unreasonable bending deformation, and the heat generated thereby changes the spring constant of the damper rubber, causing the problem that the desired damper characteristics cannot be obtained. are doing. Also,
Excessive flexural deformation of the damper rubber also tends to cause the problem of rubber breakage due to rubber deterioration due to heat.

Therefore, in the technology described in the above-mentioned publication, a torsional damper is provided on the rim portion of the pulley, and a bending damper is provided radially inward of the rim portion. Excessive vibration in this direction is controlled by the rim of the pulley.

However, when such a configuration is adopted, a new problem arises in that the damper mass for the bending damper hits the rim portion of the pulley, causing a collision noise.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an engine damper structure that suppresses excessive radial vibration of a bending damper without generating impact noise.

(Means and effects for solving the problem) The present invention provides a method for the damper rubber for the torsional damper and the damper mass for the bending damper when the torsional damper and the bending damper are arranged side by side in the axial direction of the crankshaft. This was done by focusing on the layout relationship. That is, when the torsional damper and the bending damper are arranged side by side in the crankshaft axial direction, the damper rubber for the torsional damper and the damper mass for the bending damper can be placed close to each other. Focusing on this point, the present invention forms a stepped part on the tip surface of the damper mass for a bending damper, and also provides an extension part on the damper rubber for a torsional damper that extends toward the bending damper in the axial direction of the crankshaft. The step portion and the extension portion are provided to suppress excessive radial displacement of the damper mass for the bending damper.

With this configuration, the damper mass for the bending damper is in contact with the extension of the damper rubber for the torsional damper, which is an elastic body, so excessive vibration in the radial direction of the bending damper is regulated, thereby reducing impact noise. There is no risk of this happening. Furthermore, in this case, in order to ensure the performance of the bending damper, it is necessary to secure a gap that allows the damper mass for the bending damper to vibrate to some extent in the radial direction, and to suppress excessive radial displacement of the damper mass. However, since the excessive radial displacement of the damper mass for the bending damper is suppressed by the stepped portion on the tip surface of the damper mass for the bending damper and the extension portion of the damper rubber for the torsional damper, the bending damper It is no longer necessary to arrange a regulating member for the damper mass on the radially outer side of the damper mass in consideration of the above-mentioned gap. Therefore, by suppressing excessive radial displacement of the damper mass, it is possible to prevent the present structure from expanding in the radial direction.

(Example) Hereinafter, an example of the present invention will be described based on the attached drawings.

First embodiment (Figs. 1 to 3) In Fig. 1, 1 is a pulley for a generator;
2 is a power steering pulley, and these two pulleys 1 and 2 are crankshaft (not shown)
It is fixed to the shaft end using a bolt 3.

The above-mentioned pulley 1 for a generator has an outer peripheral edge of the disk portion 1a bent to have a substantially L-shaped cross section,
A seat portion 1b is formed extending in the axial direction of the crankshaft, and a rim portion 1c is provided on the outer peripheral surface of the seat portion 1b with a rubber 4 interposed therebetween. That is, the rubber 4 and the rim portion 1c are juxtaposed in the radial direction of the crankshaft, thereby forming a torsional damper 4 in which the rubber 4 is used as a damper rubber and the rim portion 1c is used as a damper mass.

On the other hand, the power steering pulley 2 is
arranged outside the generator pulley 1,
The disk portion 2a is bolted to the crankshaft with the disk portion 1a of the generator pulley 1 interposed therebetween. The disk portion 2a has an extending portion 2b extending in the axial direction of the crankshaft, and a seat portion 2c extending radially outward from the extending portion 2b, and has a seat portion 2c extending radially outward from the extending portion 2b. The portion 2d is formed by bending the outer end of the seat portion 2c toward the crankshaft. That is, between the power steering pulley 2 and the generator pulley 1, there is a rim portion 2 of the power steering pulley 2.
d, a space A formed by the seat portion 2c, and the extension portion 2b.
is provided, and a bending damper 6 is disposed within this space A.

The bending damper 6 is composed of a damper rubber 6a and a damper mass 6b, and the damper rubber 6a is basically the seat part 2c of the pulley 2 for steering.
The damper mass 6b is juxtaposed with the damper rubber 6a in the axial direction of the crankshaft, and the damper mass 6b and the torsional damper 5 are placed close to each other. A stepped portion 7 is formed in the damper mass 6b on the surface facing the torsional damper 5. On the other hand, the damper rubber 4 for the torsional damper
is provided with an extension portion 4a extending toward the bending damper in the axial direction of the crankshaft, and the extension portion 4a extends to the stepped portion of the damper mass 6b for the bending damper. Excessive displacement of the damper mass 6b in the radial direction is suppressed.

Further, the extending portion 2b of the power steering pulley 2 is provided with a plurality of notched holes 8 at intervals in the circumferential direction, and the notched holes 8 are provided with a plurality of notched holes 8 as shown in FIG.
As shown in FIG. 3, a fin 9 is provided on the lag side of the power steering pulley 2 in the rotational direction X,
This fin 9 is formed by cutting and raising the notch hole 8 described above.

In the above configuration, excessive vibration in the radial direction of the bending damper 6 is suppressed by the step portion 7 of the damper mass 6b for the bending damper coming into contact with the extension portion 4a of the damper mass 4 for the torsional damper. Of course, since this extension part 4a is an elastic body, even if it hits the damper mass 6b for the bending damper, it will not produce an impact sound. In addition, in this embodiment, since the notch hole 8 and the fin 9 are provided in the extended portion 2b of the power steering pulley 2, the space A is filled with the rotation of the power steering pulley 2. Forced air is sent in, and the damper rubber 6a for the bending damper in particular is air-cooled by this forced air. Therefore, heat dissipation from the damper rubber 6a for the bending damper is carried out smoothly.
Therefore, the spring constant of the damper rubber 6a is prevented from changing, and the initial performance of the bending damper 6 can be maintained.

The drawings after FIG. 4 show other embodiments of the present invention, and in the following description, the same elements as in the first embodiment will be given the same reference numerals and their explanation will be omitted. , only the characteristic parts of each embodiment will be explained.

Second Embodiment (FIG. 4) In this embodiment, the fin 9 is a fin member 10 separate from the power steering pulley 2.
The fin member 10 also serves as a washer for the bolt 3.

Third embodiment (Fig. 5) In this embodiment, the generator pulley 1
is composed of a disk portion 1a and a rim portion 1d integrally formed next to the disk portion 1a, and the rim portion 1d
A torsional damper 5 is disposed radially inwardly. The torsional damper 5 includes a damper rubber 5a attached to the inner surface of the rim portion 1d;
and a damper mass 5b disposed inside the damper rubber 5a, and the torsional damper damper rubber 5a has an extension portion 5b extending toward the bending damper in the axial direction of the crankshaft.
is provided, and is designed to restrict excessive radial vibration of the bending damper 6 by the extension portion 5b.

(Effect of the invention) As is clear from the above explanation, according to the invention, excessive radial vibration of the bending damper can be suppressed by the extension of the damper rubber for the torsional damper, which is an elastic body. Therefore, excessive vibration of the bending damper can be suppressed without generating any impact noise. By suppressing excessive radial displacement of the damper mass for the bending damper, it is possible to prevent the present structure from expanding in the radial direction.

[Brief explanation of the drawing]

1 to 3 show a first embodiment of the present invention, in which FIG. 1 shows a torsional damper and a bending damper disposed at the end of a crankshaft, and FIG. 2 is a front view of a pulley provided with a torsional damper and a bending damper, and FIG. 3 is a front view of a pulley provided with a torsional damper and a bending damper. It is a figure which shows the notch hole and fin provided. Figure 4 is the second version of this invention.
Embodiment FIG. 5 is a sectional view showing a third embodiment of the present invention. 1... Generator pulley, 1c... Generator pulley rim part (damper mass for torsional damper), 2... Power steering pulley, 4... Damper rubber for torsional damper, 4a... Damper rubber for torsional damper. Extension part, 5... Torsional damper, 6...
Bending damper, 6a... Damper rubber for bending damper, 6b... Damper mass for bending damper.

Claims (1)

[Claim for Utility Model Registration] A torsional damper in which a damper mass and damper rubber are arranged side by side in the radial direction, and a bending damper in which a damper mass and damper rubber are arranged in parallel in the axial direction are provided at the shaft end of the crankshaft. In the damper structure of the engine, the torsional damper and the bending damper are arranged in parallel in the axial direction of the crankshaft, and a damper is provided on the tip surface of the damper mass of the bending damper over the entire circumference in the circumferential direction of the damper mass. A stepped portion is formed in the damper rubber of the torsional damper.
A damper structure for an engine, comprising: an extension extending toward the bending damper in the axial direction of the crankshaft, and a tip end of the extension extends into the step.