Vibration damping device

Abstract

A vibration damping device is disclosed, including a laminated sheet (20) having at least its inner region fixed on a side plate (11) of a bucket (10) of a construction machine; the inner region is located within an area G composed by the following regions: i) a region D composed by a point B where a section CA is crossed with circumference of the laminated sheet (20), a central point d of a connection section BC of a circular-arc center C and surrounding of the central point D, wherein the section CA is the circular-arc center C which is connected to at least a part of one side and provided with the side plate (11) in approximate circular-arc shape, and the connection section of a point A transported from the approximate circular-arc shape into other shapes at one side where the bucket (10) is installed on the construction machine; ii) a region F composed by a central point f of the section CA and the surrounding of the central point f; iii) a region between the region D and the region F. Thereby, the disadvantageous impact on the vibration damping effect, which is caused by the fixed laminated sheet, can be inhibited to the minimum.

Description

[0001] This application is a divisional application, the application number of its parent application is: 03820847.4, the application date: 2003.9.2, the name of the invention: vibration damping device and bucket of construction machinery technical field [0002] The present invention relates to a vibration damping device for reducing noise emitted from a base material by suppressing vibration generated in the base material. Background technique [0003] In recent years, people have asked construction machinery to reduce noise especially in residential areas when working at night, and various countries have also introduced noise-related regulations that limit noise below a certain level. For example, in the case of using a hydraulic excavator equipped with a working machine including a bucket, it has been confirmed through experiments that the bucket is a main source of noise. It is estimated that about 80% of the noise emitted from the work machine is the noise emitted from...

AI Technical Summary

Problems solved by technology

[0010] The first problem is that a gap is generated between the thin plates 21, 21' constituting the laminated plate 20 and also between the side plate 11 and the laminated plate 20 due to thermal deformation generated in the welding process during manufacture.

[0011] The second problem is: in the actual use of construction machinery, it often occurs that the side plate 11 is subjected to a large external force such as the bucket colliding with rocks.

However, since the periphery of the inner plate 151 of the laminated plate 150 is welded all around to constrain the entire circumference, its vibration damping performance is low.

On the contrary, if intermittent welding is performed on the periphery of the laminated plate 150 in order to improve the vibration damping performance by reducing the restraint points, rainwater will infiltrate into the interior and cause rust.

[0025] (2) If the prescribed gap d1 cannot be ensured between the laminated plate 150 and the wear-resistant plate 108 at the time of manufacture, sufficient welding quality cannot be obtained

On the other hand, when the positions of the inner plate 151 and the outer plate 152 are determined to secure the gap d1, more steps are required, resulting in an increase in cost.

[0026] (3) Due to the large volume of the welded part, more steps are required and the cost increases

On the contrary, if intermittent welding is performed around the laminated plate 150 in order to reduce the amount of welding, as in the case of (1) above, rainwater will infiltrate the inside and cause rust.

[0027] (4) In order to prevent swelling or deformation caused by thermal deformation during continuous welding, it is necessary to temporarily weld the laminated plate 150 and the side plate 103 at very many points, which not only requires a process, but also increases the cost.

In this case, since the entire circumference is restrained by welding the circumference of the inner plate 161 of the laminated plate 160 similarly to the case of (1) above, its vibration damping performance is poor.

On the contrary, if intermittent welding is performed around the laminated plate 160 in order to reduce restraint points and improve vibration damping performance, rainwater will infiltrate the interior and cause rust.

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