JPS6227730Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a damper that damps torsional vibrations applied to rotating shafts such as crankshafts, camshafts, or drive shafts of internal combustion engines, and prevents accidents such as breakage of the rotating shafts. be.

In recent years, a type of damper called a viscous rubber damper has come into use. An example of a conventional product of this viscous rubber damper will be explained with reference to FIG. A peripheral edge portion 3a of a substantially disc-shaped mounting plate 3 is formed on the inner peripheral side with a concave portion 2 that opens radially inward and continues in the circumferential direction, and is disposed coaxially with the inertial mass body 1. An annular rubber body is inserted into the recess 2 of the inertial mass body 1 and between the mutually opposing inner wall surfaces 2a, 2a' near the open end of the recess 2 and the front and back surfaces 3b, 3b' of the mounting plate 3, respectively. 4, 4' are disposed coaxially with the inertial mass body 1, and the mounting plate 3 and the inertial mass body 1 are elastically connected by these rubber bodies 4, 4'. Inner back part 2b
A narrow gap between the mounting plate 3 and the peripheral edge 3a of the mounting plate 3, that is, a gap closed by the rubber bodies 4 and 4', is filled with a viscous fluid 5 such as silicone oil. In such a damper,
If the mounting plate 3 is fixed to a rotating shaft 6 such as a crankshaft, the initial torsional vibration will be absorbed by the shear resistance of the viscous fluid 5 and the elasticity of the rubber bodies 4, 4', and the resonance of the rubber will be absorbed. It is known that the secondary vibration caused by the rubber damper is absorbed by the shear resistance of the viscous fluid 5, thereby exhibiting much better torsional vibration damping characteristics than a normal rubber damper.

However, in such a viscous rubber damper, since the peripheral portion 3a of the disk-shaped mounting plate 3 is inserted into the inward recess 2 of the annular inertial mass body 1 as described above, it is not possible to construct the entire inertial mass body 1 as a single piece. Therefore, in the conventional damper, the damper is constructed of a pair of divided pieces 1A, 1B as described above, and the divided pieces 1A, 1B are fixed to the mounting plate 3.
After setting the divided pieces 1A and 1B in the specified positions,
In the past, the inertial mass 1 was usually connected and fixed by a fastening means such as "caulking" or welding. However, the inertial mass 1 is made up of a pair of split pieces 1A, as shown in FIG.
In order to obtain the upper split piece 1A in FIG. 1, it is necessary to cut the upper split piece 1B to a predetermined thickness _t1 as shown by the imaginary line in FIG. 2A.
A square-shaped material 7A having a peripheral portion 7
The intermediate member 8A is then cut into a circular shape by melting or the like to obtain a hollow annular intermediate member 8A.
As shown in FIG. 2B, the intermediate material 8A is cut into the imaginary diagonal line portion 8 in FIG. 2B until the divided piece 1A has the same shape and dimensions as the divided piece 1A.
In order to obtain the lower divided piece 1B in FIG. 1, it is normal to cut the lower divided piece 1A in FIG.
As shown by the imaginary line, a square blank 7 having a thickness _t2
B is prepared, and the peripheral portion 71B and the central portion 72
B is cut into a perfect circle in the same manner as above to obtain a hollow annular intermediate material 8B, and then, as shown in FIG.
The third step is to obtain the shape and dimensions of the divided piece 1B.
The imaginary shaded portions 81B, 82B, and 83B in FIG. B are usually cut, but since the axial length (thickness) t ₁ ' of the divided piece 1A is relatively small,
The thickness t1 of the blank _7A is also relatively thin, and therefore the volume of the peripheral portion 71A and the central portion 72A to be cut off from the blank 7A is also relatively small, and the volume of the portion 81A to be cut and removed from the intermediate material 8A is also relatively small. In contrast, the maximum axial length _t2 ' of the divided piece 1B is more than two and nearly three times the thickness t1 _' of the divided piece 1A, so that a blank 7B having a considerably large thickness _t2 must be used. As a result, the volume of the peripheral portion 71B and the central portion 72B to be cut off from the blank 7B is large, and the volume of the portion 81A to be cut and removed from the intermediate material 8A is also relatively small.
Since the volume of the intermediate material 8B, 82B, and 83B, accounts for more than half of the entire intermediate material 8B, when machining the divided pieces 1B in particular, a large amount of scrap or chips is generated, resulting in a very poor material yield, and the time required for the melt-cutting and cutting processes is very long. As a result, the cost of the entire damper was inevitably high.

This invention was made in view of the above circumstances, and aims to provide a viscous rubber damper with a structure that has a good material yield and is easy to process.

Figures 4 and 5 below are examples of this invention.
This will be explained in detail with reference to the drawings. Note that in each of the following embodiments, the parts other than the inertial mass body 1 are the same as those of the conventional damper, so a description thereof will be omitted.

FIG. 4 shows a first embodiment of this invention, in which the inertial mass body 1 has a first annular divided piece 11 facing one plate surface of the peripheral edge 3a of the mounting plate 3. , an annular second divided piece 12 facing the other plate surface of the peripheral edge part 3a, and the peripheral edge part 3.
and a third annular divided piece 13 facing the outer peripheral end surface of a. The first divided piece 11 is made to have substantially the same shape as one divided piece 1A in the conventional example, and the second divided piece 12 is made to have a shape symmetrical to the first divided piece 11. On the other hand, the third divided piece 13
are the outer peripheral surface of the first divided piece 11 and the second divided piece 1
A protrusion 1 that is made to entirely cover the outer peripheral surface of 2 and continues in the circumferential direction at the center of the inner peripheral surface.
3a is formed, and this protrusion 13a is inserted between the first divided piece 11 and the second divided piece 12 to face the outer peripheral surface of the mounting plate 3, and furthermore, a thin strip is formed on both edges in the width direction. High quality projecting edges 13b, 13b' are formed, and these projecting edges 13b, 13b' are caulked to the corners of the first divided piece 11 and the second divided piece 12.

In the embodiment shown in FIG. 4, the third divided piece 13
The means for fixing the first divided piece 11 and the second divided piece 12 to the corner portions is not limited to "caulking" but may be welding.

FIG. 5 shows a second embodiment of this invention. In this embodiment, the third divided piece 13 is made in an annular shape with a rectangular cross section, and this third divided piece 13 is connected to the first divided piece 11 and Stepped notches 11 formed in the corners of the outer periphery of the second divided piece 12 on the sides closer to each other
a, 12a, and the third divided piece 13
The end faces in the width direction are welded 14 to the first divided piece 11 and the second divided piece 12.

According to the second embodiment shown in FIG. 5, since a rectangular piece with a simple cross section is used as the third divided piece 13, the cost is lower than that of the first embodiment. is obtained.

Note that the third divided piece 13 has a radial thickness of the first
Since it is much smaller than the divided piece 11 and the second divided piece 12, a processing method that does not use cutting, such as a processing method in which a straight steel piece is curved and its both ends are joined to form an annular shape, or It can be created by a press working method or the like.

As is clear from the above description, in the damper of this invention, the inertial mass body 1 is divided into a first divided piece 11 and a second divided piece 12 which face the front and back surfaces of the peripheral edge 3a of the mounting plate 3, and the mounting plate 3. This is obtained by coaxially fixing the third divided piece 13 facing the outer peripheral end surface of the third divided piece 13 . That is, in the inertial mass body 1, the portion facing each plate surface of the peripheral edge portion 3a of the mounting plate 3 and the portion facing the outer peripheral end surface are made separately. Here, the first divided piece 11 and the second divided piece 12 are usually made by cutting, but they can be made in almost the same shape as the upper divided piece 1A in the conventional example. Similar to the processing of the divided piece 1A, there are relatively few scraps or chips, and the processing operation is also relatively easy. On the other hand, as described above, the third divided piece 13 has a much smaller thickness in the radial direction than the first divided piece 11 and the second divided piece 12, and therefore can be produced at low cost without using cutting. can do. Therefore, inertial mass 1
Overall, the material yield is much better than that of conventional materials, and it is also easy to process.

Therefore, the damper of this invention can significantly reduce the material cost and processing cost required for the inertial mass body compared to the conventional ones, and can advantageously lower the cost of the damper as a whole.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view showing an example of a conventional viscous rubber damper, and Fig. 2 shows the step-by-step machining process of one divided piece 1A of the inertial mass body 1 used in the damper shown in Fig. 1. FIG. 3 is a schematic diagram showing step-by-step the processing process of the other divided piece 1B of the inertial mass body used in the damper shown in FIG. 1, and FIG. FIG. 5 is a vertical sectional view showing a damper according to a second embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Inertial mass body, 2... Recessed part, 3... Mounting plate, 4, 4'... Rubber body, 5... Viscous fluid, 11
...First divided piece, 12...Second divided piece, 13...
Third segment.

Claims (1)

[Claims for Utility Model Registration] A concave portion that opens radially inward and continues circumferentially is formed on the inner peripheral side of the inertial mass body, which is generally annular as a whole, and is coaxial with the inertial mass body. The peripheral edge of the approximately disk-shaped mounting plate arranged in such a manner is inserted into the recess, and an annular rubber body is inserted between the inner wall surface near the opening end of the recess and the front and back surfaces of the mounting plate, respectively. arranged coaxially with
A damper for torsional vibration prevention in which the mounting plate and the inertial mass body are elastically connected by these rubber bodies, and the gap between the innermost part of the recess and the peripheral edge of the mounting plate is filled with viscous fluid. In, the inertial mass body includes a first annular divided piece facing one plate surface near the peripheral edge of the mounting plate, and a second annular divided piece facing the other plate surface near the peripheral edge of the mounting plate. and an annular third portion facing the outer peripheral end surface of the mounting plate.
A damper characterized by having a structure in which a divided piece and a divided piece are coaxially fixed and integrated.