JP3348574B2 - Operator's cab vibration isolator for construction machinery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration isolator for a driver's cab in a construction machine such as a hydraulic shovel, which suppresses the vibration of a window glass provided in the driver's cab.

[0002]

2. Description of the Related Art As an example of a construction machine, a hydraulic excavator, for example, as shown in FIG. 10, has a vehicle in which a crawler type lower traveling body 1 is provided with an upper rotating body 2 so as to be able to swing. The front working mechanism is attached to the body 2. The front working mechanism has an arm 4 rotatably connected to the top end of a boom 3 provided on the upper swing body 2 so as to be capable of raising and lowering. A front working mechanism is provided. The upper revolving unit 2 further includes a cab 6
Is installed, and the operator gets on the cab 6 and performs the operation.

The hydraulic excavator performs an operation such as excavation of earth and sand by a front operation mechanism, and also allows the vehicle to travel by the lower traveling body 1. When the vehicle is traveling by the lower traveling body 1 or working by the front working mechanism, vibration occurs in the entire vehicle. This vibration is also transmitted to the cab 6, but in order to improve the working environment of the operator operating in the cab 6, the cab 6 is attached to the upper revolving unit 2 by vibration-proofing means such as vibration-proof rubber. Is installed through. Thereby, the vibration in the cab 6 and the noise caused by the vibration are reduced.

[0004]

By the way, windows are provided in the driver's cab in order to obtain an external view, and these windows are fitted with window glass. The windows are formed on the four peripheral walls of the cab, and substantially the entire surface is a window on the front surface and on both right and left sides in order to obtain a view as wide as possible. However, since the door is provided on one side in order for the operator to get in and out of the cab, the windows are dispersed at a plurality of locations with a small area. On the other hand, a large window is provided in the front part and the side part on the side where the door is not provided.

As described above, the cab is supported in a vibration-proof manner, but the vibration-proof support alone cannot completely prevent the transmission of vibrations into the cab. Vibration also reaches the window glass through the mounting part of the window frame, but in order to suppress the vibration of the window, a weather strip, dam rubber, etc. are attached around the window glass, and these are used as cushioning materials. Because it functions, the transmission of vibration to the window glass is suppressed. However, vibration cannot be completely absorbed only by this cushioning material. Here, the vibration in the window glass includes a high-frequency vibration and a low-frequency vibration,
High-frequency vibration generates rattling noise, and low-frequency vibration generates undulating muffled sound.

When the window glass is elastically supported by the cushioning material, high frequency vibrations can be absorbed to some extent, but not completely. In addition, since the windowpane is substantially in a non-fixed state, low-frequency vibration due to resonance is rather large, and thus, in the cab, for the operator,
An extremely unpleasant so-called muffled sound is generated, which is a factor that deteriorates the working environment of the operator. In particular, the muffled sound caused by low-frequency vibration is not so large in a window glass having a small area, but the window glass on the front surface and one side surface has a large area. Extremely loud, producing a louder sound.

The present invention has been made in view of the above points, and an object of the present invention is to suppress the vibration of a window glass as much as possible to reduce the noise in the driver's cab and improve the working environment. It's about getting it right.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention suppresses the vibration of a window glass mounted on a window frame of a cab of a construction machine via a cushioning material during operation. A bar is fixedly provided at both ends to the structure of the cab, and a beam damper made of an elastic body is connected to the beam, and the beam damper is attached to the window glass. Weight
It is characterized in that it is configured to be in contact with the center position or its vicinity .

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In order to suppress the vibration of a window glass, a support member is provided, a vibration damping member made of an elastic body is attached to the support member, and the vibration damping member is brought into contact with the surface of the window glass. The support member is fixed to a portion other than the window glass, for example, an appropriate portion such as a window frame or a wall portion forming a structure of a cab. Thereby, the vibration of the window glass can be suppressed, the noise is reduced, and the working environment of the operator is improved.

As for the window glass, both the high-frequency vibration and the low-frequency vibration increase as the area increases. Therefore, suppression of vibration by the vibration damping member is particularly effective in the case of a window glass mounted on a large window. Of the windows provided on the four sides of the operator's cab, the window glass on the side surface opposite to the side surface on which the window glass and the door are provided has a large area. However, it is extremely important to secure the field of view of the window on the front side, and there are cases where a member that obstructs the field of view and generates a blind spot cannot be provided. Although it is necessary to secure the field of view also on the side window glass, the demand for securing a wide field of view is not so large as compared with the front window. Therefore, a vibration damping mechanism using a vibration damping member is provided at least on the side of the window glass on the side surface.

When the vibration is transmitted to the window glass, rattling sound due to high frequency vibration and muffled sound due to low frequency vibration are generated. Since the movement of the window glass is regulated by the damping member, not only rattling noise can be suppressed, but also resonance can be suppressed, and muffled noise due to low-frequency vibration can be effectively suppressed.

If the number of damping members is increased or the area of contact with the window glass is increased, the damping effect is improved. However, you must not obstruct your view too much.
In order to ensure a wide field of view as much as possible and to exhibit the maximum damping function, particularly the function of suppressing muffled sound due to resonance, the damping member is disposed at or near the center of gravity of the window glass. Then, in order to damping member is not separated from the window glass at the time of vibration, vibration damping member is pressed against the window glass to the extent that slightly elastically deformed. The pressing force of the vibration damping member against the window glass may be adjusted based on the relationship with the mounting mechanism around the window glass. Instead of simply pressing the vibration damping member against the window glass, it is also possible to hold the two members fixedly. For this purpose, for example, a suction cup is provided at a contact portion of the damping member with the window glass, and the damping member is adsorbed to the window glass.

The vibration damping member is mounted on a support member, and the support member is fixed to a structure other than the window glass. This support member can be formed in a rod shape and fixed to the window frame or the inner wall of the cab. Here, in the case of a micro turning machine in a hydraulic excavator, the front working mechanism is disposed very close to the window on the side, and when the boom and the arm are folded, the side working is Will be displaced at a position where there is almost no gap with respect to the window. In this part, the window with the windowpane is not opened, but in consideration of the time when the windowpane is damaged, etc. Some are provided with a crosspiece. In this case, the beam can be shared with the support member, and a vibration damping member can be provided at a predetermined position of the beam.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. In the following embodiments, a vibration damping mechanism is provided on a window glass provided on a side surface opposite to a side provided with a door in a cab of a hydraulic shovel as a construction machine, and furthermore, an operator is provided on the window glass. I will explain what provided a crosspiece to protect it from appearing,
The present invention is not limited to the cab having such a configuration.

First, in FIG. 1 and FIG.
Is a column, which is a structure of a driver's cab in a vehicle such as a hydraulic shovel, etc., 11 is a connecting plate portion provided between the columns 10, 10 at a lower portion of the driver's cab, and 12 is a roof at an upper portion. A portion surrounded by the columns 10, 10 and the connecting portion 11 and the roof 12 is a window 13, and this window 1
3 is provided with a transparent window glass 14.

Reference numerals 15a to 15c denote guard bars which are provided at predetermined intervals in the up-down direction and are arranged so that the window 13 extends across the left and right. The three bars 15a to 15c
On the inner side of the cab, both ends are fixed to the columns 10, 10 by screws or the like. Here, the bar 15a ~
Reference numeral 15c denotes a block for preventing the operator from getting out of the window 14 through the window 14 while the operator is seated in the driver's seat in the cab. I try to plan.

The window glass 13 has a considerably large area,
Its center of gravity is at the position indicated by G in FIG. A holder 16 is connected to an intermediate portion between the bars 15b and 15c near the position G of the center of gravity. The holder 16 is shown in FIG.
As shown in FIG. 7, by bending the metal plate body, a pair of holding plate portions 16a, 16a and the holding plate portions 16a, 16a are formed.
A continuous portion 16b having a curved shape that connects the portions 16a is provided. The continuous portion 16b is attached so as to straddle the bars 15b and 15c, and is fixed by means such as welding. And
A rubber block 17 is mounted as a vibration damping member between the holding plate portions 16a and 16b of the holder 16, and is fixed by means such as bonding or screwing. Therefore, the bars 15 b and 15 c provided with the holder 16 function as support members for the rubber block 17. The rubber block 17 is used for the window glass 1.
4 for exerting a vibration damping function for suppressing vibration of the beam 4. When the bars 15b and 15c are attached to the support 10,
The rubber block 17 is pressed against the window glass 14 and becomes elastically deformed to some extent.

This embodiment is configured as described above. When the vehicle is driven or the front working mechanism is operated, vibration is generated. It is also transmitted to the window glass 14. However, since the rubber block 17 is in contact with the window glass 14 and the rubber block 17 is pressed against the window glass 14 with a predetermined pressing force at a position near the center of gravity G of the window glass 14, Movement is regulated.
As a result, the rattling sound due to the high frequency minute vibration is suppressed. However, since the rubber block 17 is brought into contact with this portion with a predetermined pressing force, the muffled noise is extremely effectively suppressed by restricting the movement. As a result, noise in the cab is reduced and the working environment for the operator is improved.

FIGS. 4 and 5 show a second embodiment. In the first embodiment, the rubber block is fixed to the holder of the crosspiece. In the example, the configuration is such that the pressing force against the window glass 14 can be adjusted. For this purpose, the crosspiece 20 is formed of a pipe-shaped member and is divided into left and right parts to form crosspiece members 20a and 20b.
b, and the space between the crosspiece members 20a and 20b is
It is a crosspiece connecting member 20c. This beam connecting member 20c
Is flattened by flattening the pipe, and the holder 21 is in contact with the crosspiece connecting member 20c. The holder 21 has a box shape with one end opened, and a vibration damping member 24 provided by fixing a metal plate 23 to a rubber block 22 is fitted inside the holder 21. In the vibration damping member 24, a sheet metal 23 is disposed in a holder 21, and a rubber block 22 projects from an open end of the holder 21 by a predetermined length.

A pair of bolt insertion holes 25 are formed in the crosspiece connecting member 20c on the left and right, and a bolt insertion hole 26 is provided in the end plate portion of the holder 21 at a position corresponding to the bolt insertion hole 25. Have been. A bolt 27 is inserted through the bolt insertion holes 25 and 26, and nuts 28 and 29 are provided outside the beam connecting member 20c of the bolt 27 and inside the holder 21, respectively. 21 and cannot be rotated. Accordingly, by screwing the nut 28 to adjust the length of the bolt 27 in the holder 21, the length of the rubber block 22 projecting from the holder 21 can be adjusted.

With the above construction, the nut 28 is screwed in a state in which the crosspiece 20 is connected to the support, and the rubber block 22 of the vibration damping member 24 provided in the holder 21 is in contact with the window glass 14. By moving the bolt 27 in the axial direction, the protrusion length of the rubber block 22 from the holder 21 is adjusted.
The window glass 14 of the rubber block 22 is bent in the state shown by the dotted line to be bent to the state shown by the solid line so that the vibration can be absorbed most effectively according to the vibration frequency and the like.
Pressing force can be adjusted.

FIGS. 6 and 7 show a third embodiment. In this embodiment, a rubber block 30 is used as an anti-vibration member. This rubber block 30
Has a concave-shaped abutting portion 31 at the distal end, and a connecting portion 32 at the base end having a concave shape of a semicircle or more. In order to attach the rubber block 30 to the crosspiece 33, the connecting portion 32 is elastically engaged with the crosspiece 33 so as to hold the crosspiece 33, and the contact portion 31 is attached to the window glass 14. At this time, the rubber block 30 is pressed against the window glass 14 and the concave curved contact portion 31 is in an expanded state. Since the contact area is increased, the vibration damping efficiency is improved. In addition, with this configuration, the rubber block 30 can be attached and detached without separating the crosspiece 33 from the support, so that when the rubber block 30 is deteriorated or damaged, the rubber block 30 is replaced. Work becomes easier.

FIGS. 8 and 9 show a fourth embodiment of the present invention. In this embodiment, as a vibration damping member 40, a sucker 4
2 is used. And rubber block 4
As in the third embodiment described above, the base portion 1 has a connecting portion 43 having a concave shape of a semicircle or more, and this connecting portion 43 is elastically engaged with a bar 44, It is attached so as to hold the bar 44. A plurality of vibration damping members 40 can be mounted on the bar 44.

With the above construction, the window glass 14 is adsorbed by the suction cup 42, and in the thickness direction thereof,
Since the movement in the direction approaching 2 and the movement in the direction away from the suction cup 42 are also regulated, the vibration suppressing function is further improved. Further, since the damping member 40 can be moved in the axial direction of the bar 44,
Can be set to any position. Further, the vibration damping member 40 can be replaced without separating the bar 44 from the column.

[0025]

As described above, according to the present invention, a vibration damping member made of an elastic material is connected to a crossbar fixedly provided at both ends to a structure of a driver's cab, and a vibration having the largest amplitude when vibration is generated.
Since the vibration damping member is configured to abut on or near the center of gravity of the vibrating window glass, vibration generated in the window glass mounted on the mounting portion of the window frame via the cushioning material can be suppressed. This has the effect of reducing noise and improving the working environment of the operator.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory view showing a window on a side portion of a cab according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is an enlarged sectional view taken along the line Y ₁ -Y ₁ of FIG. 2;

FIG. 4 is a sectional view similar to FIG. 2 in a second embodiment of the present invention.

FIG. 5 is an enlarged sectional view taken along the line Y ₂ -Y ₂ of FIG. 4;

FIG. 6 is a sectional view similar to FIG. 2, showing a third embodiment of the present invention.

FIG. 7 is an enlarged sectional view of Y ₃ -Y ₃ of FIG. 6;

FIG. 8 is a sectional view similar to FIG. 2, showing a fourth embodiment of the present invention.

FIG. 9 is an enlarged sectional view taken along line Y ₄ -Y ₄ of FIG. 8;

FIG. 10 is an external view of a hydraulic shovel as an example of a construction machine.

[Explanation of symbols]

 6 Operator's cab 10 Support 11 Connecting plate 12 Roof 13 Window 14 Window glass 15a to 15c, 20, 33, 44 Bar 16, 21 Holder 17, 22, 30, 41 Rubber block 23 Sheet metal 24, 40 Damping member 27 Bolt 31 Contact part 32, 43 Contact part 42 Sucker

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60J 1/00 E04B 1/98

Claims (4)

(57) [Claims] An object of the present invention is to prevent a window glass mounted on a window frame of a driver's cab of a construction machine via a cushioning material from vibrating during operation. Fix and cross (15b)
A damping member (17) made of an elastic material is connected to the bar (15b), and the damping member (17) is attached to the window glass.
(14) A vibration isolator for a cab of a construction machine, which is configured to be brought into contact with the position of the center of gravity (G) or in the vicinity thereof . 2. The construction machine according to claim 1, wherein said vibration damping member (17) comes into contact with a position for reducing noise caused by low frequency vibration of said window glass (14). Cab vibration isolator. 3. The cab vibration isolator of a construction machine according to claim 1, wherein said vibration damping member (17) is a block-shaped rubber (22) or a suction cup (42). 4. The cab vibration isolator of a construction machine according to claim 1, wherein the vibration damping member (17) is configured to be able to adjust a pressing force against the window glass (14).