JPS5832038Y2 - Combination vibration absorber - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a combination vibration absorbing device for reducing vibrations of mechanical equipment.

2. Description of the Related Art In general, the method shown in FIG. 1 is known as a means for reducing vibrations of mechanical devices.

In FIG. 1, 1 is a mechanical device, 2 is a floor on which the mechanical device 1 is installed, and 3 is a vibration-proof rubber that is interposed between the bottom of the mechanical device 1 and the floor 2 to support the mechanical device 1.

The vibration isolating means having such a structure prevents the vibration from being transmitted to the floor 2 when vibration occurs in the mechanical device, or suppresses the vibration of the mechanical device 1 itself to a low level.
Furthermore, it is used to prevent vibrations from other places from being transmitted from the floor 2 to the mechanical device 1.

Note that the mechanical device 1 is considered as a rigid body, and the arrows in FIG. 1 indicate the directions of vibration.

However, even if the vibration isolating rubber 3 is used as described above, there may be cases where the vibration of the mechanical device 1 is larger than the required value, or when the vibration isolating rubber 3 is used.
By using this, vibrations are not transmitted to the floor 2, but if the vibrations of the mechanical device 1 become large,
As shown in FIGS. 2 to 4, a vibration absorber (dynamic damper) 6, which is a combination of a cantilever beam 4 and a weight 5, is used together with the vibration isolating rubber 3.

Generally, the frequency of vibration generated from the mechanical device 1 is f.

Then, there is a relationship fl(fO) between the natural frequency f1 formed by the mechanical device 1 and the vibration isolating rubber 3.

Therefore, the natural frequency given to the vibration absorber 6 shown in FIG. 2 can be adjusted by the cantilever beam 4 and the weight 5, and the vibration absorber 6 can be operated by making it match the frequency f1. become.

Conventionally, the combination of the mechanical device 1 and the vibration absorber 6 is generally
As shown in the figure, the vibration absorber 6 is installed near the center of the mechanical device 1. If it is impossible to install the vibration absorber in the center due to the structure of the mechanical device 1, the structure shown in FIG. A cantilever beam 4 and a weight 5 were provided on one side of the mechanical device 1.

Although this can reduce the vibration of the mechanical device 1 in many cases, there are cases where it is insufficient to suppress the vibration to a minute level.

The reason for this can be explained using Fig. 4. In the figure, the part where the vibration absorber 6 is attached becomes a node of the vibration mode due to the action of the vibration absorber, and the vibration becomes small, but the vibration at the symmetrical position is large, and the whole As a result, it vibrates as shown by the broken line in Figure 4.

Therefore, the purpose of this invention is to sufficiently reduce vibrations by adding vibration absorbers such as those described above at appropriate positions.

An embodiment of this invention will be described below with reference to FIGS. 5 and 6.

In these figures, 1 is a mechanical device, 2 is a floor, 3 is a vibration isolator, and 6 is a vibration absorber with a weight 5 attached to a cantilever beam 4. Figure 2,
It is similar to that in FIG.

The two vibration absorbers 6 are arranged at the upper part of the mechanical device 1 at symmetrical positions with respect to the center of gravity G on a straight line passing through the center of gravity G of the mechanical device 1 when viewed from the top surface of the mechanical device 1.

Since the vibration absorber 6 is arranged as described above, the 2 shown in FIG.
Not only in the case of a vibration direction parallel to the direction in which the vibration absorbers 6 are arranged, but also in the case of a vibration direction perpendicular to this direction, the vibrations at the two locations where each vibration absorber 6 is attached are absorbed, so the mechanical device 1 vibration can be efficiently reduced.

In this invention, two vibration absorbers 6 are provided in the ones shown in FIGS. 5 and 6, but if it is desired to further reduce the amount of vibration, the number of vibration absorbers may be increased. It is effective to provide a plurality of them symmetrically on a straight line passing through the center of gravity G when viewed from above.

As explained above, this invention has the effect of being able to efficiently and sufficiently reduce the vibration of mechanical equipment by installing multiple vibration absorbers at the upper part of the mechanical equipment at symmetrical positions with respect to the center of gravity of the equipment. There is.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an example of a mechanical device installed using vibration isolating rubber, and Figs. 2 and 3 are front views showing different examples of conventional combination vibration absorbing devices for mechanical devices. 4 is a top view of the vibration absorbing device shown in FIG. 3, and FIGS. 5 and 6 are a front view and a plan view showing the vibration absorbing device according to an embodiment of this invention. 1... Mechanical equipment, 2... Floor, 3...
... Anti-vibration rubber, 4 ... Cantilever beam, 5 ...
- Weight, 6... Vibration isolator. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (2)

[Scope of utility model registration request] (1) A combination vibration absorbing device characterized in that a plurality of vibration absorbers each having a weight attached to a cantilever beam supported at one end are installed in the upper part of the mechanical device at symmetrical positions with respect to the center of gravity of the mechanical device. . (2) The combination vibration absorbing device according to claim 1, wherein the vibration absorbing device is arranged on a straight line passing through the center of gravity of the mechanical device when viewed from the top surface of the mechanical device.