JP3301666B2 - Hydraulic excavator cab anti-vibration support device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to relates to a cab vibration isolation support system for supporting the upper rotating body through an anti-vibration apparatus cab of the hydraulic shovel.

2. Description of the Related Art A hydraulic excavator as a construction machine is configured such that an upper revolving structure is rotatably provided on a lower traveling structure provided with a crawler belt for traveling. The upper revolving structure includes a front work comprising a boom, an arm and a bucket. A mechanism is provided. In addition to the above-mentioned front working mechanism, a driver's cab is provided on the upper revolving superstructure, and in addition thereto, machines such as an engine and a hydraulic pump are provided, and further, members such as a counterweight are mounted. ing.

FIG. 4 shows the structure of the upper swing body. In FIG. 1, as a structure 1 of an upper revolving structure, a plurality of main structural members 2 extending in the front-rear direction of the vehicle and a plurality of appropriate portions between the main structural members 2 are stretched. And the horizontal structural member 3 provided as described above. Brackets 4 and 4 are fixedly attached to two of the main structural members 2 substantially at the center, and the base ends of the booms constituting the front working mechanism are attached to the brackets 4 and 4. Be linked. Then, between the main structural member to which the bracket 4 is attached (indicated by reference numeral 2a in the drawing) and an end-side main structural member (indicated by reference numeral 2b in the drawing).
And a driver's cab 5 is installed at an upper position thereof .

[0004] The vehicle vibrates violently during traveling or work, but the driver's cab 5 is mounted on the structure 1 via a vibration isolating support mechanism in order to minimize the transmission of this vibration to the driver's cab 5. ing. That is, as shown in FIG. 5, the vibration isolator 1 is provided at six places (or four places) in the structure 1.
0 is provided, the cab 5 of the structure 1, this
The lower part of the cab 5 is supported by the vibration isolator 10. Here, the mounting position of the vibration isolator 10, first, the anti-vibration device 10 since such is necessary to provide a hole for mounting, to be located in the lower portion of the cab 5
However, since it cannot be provided on the side of the main structural members 2a and 2b which need to maintain extremely high strength, it is provided on the side of the horizontal structural member 3.

[0005] Here, when the vehicle is run or when excavation of earth and sand and other operations are performed, a considerably large load acts on the horizontal structural member 3. In addition, although the driver's cab 5 is supported by the transverse structural member 3 though the vibration isolator 10 is interposed therebetween, a torsional force or a bending force acts on the transverse structural member 3, resulting in the operation. Low-frequency vibrations are transmitted to the room 5, and the ride comfort is poor for the operator. For this reason, since the horizontal structural member 3 is required to have high rigidity, of the three horizontal structural members 3 provided at the portion where the driver's cab 5 is mounted, the horizontal structural member 3a at the forefront is provided.
Anyway, the rigidity of the other horizontal structural members 3b and 3c is improved by adopting a closed cross-sectional structure.

FIG. 6 shows a cross section of the vibration isolator 10 mounted on the horizontal structural members 3b (and 3c). The vibration isolator 10 has a cylindrical main body 11 formed in a cylindrical shape.
A bottom plate 12 is connected to a lower part of the base member, and an elastic member 13 such as rubber is attached to an upper part of the base member. And this damping force generating chamber 1
A working fluid having a high viscosity such as, for example, silicone oil is sealed in the inside 4. The elastic member 13 includes the connecting member 1
The lower end of the connecting member 15 faces the inside of the damping force generating chamber 14 and is connected to the movable plate 16. A receiving plate 17 is connected to a portion of the connecting member 15 projecting outside the elastic member 13, and a distal end side of the receiving plate 17 is a threaded portion. Further, a mounting plate 18 having a substantially square outer shape is fixedly provided near the upper end of the cylindrical main body 11. At four corners of the mounting plate 18, bolt insertion holes 18a for inserting bolts 19 are formed.

The anti-vibration device 10 has the above configuration, and the horizontal structural member 3 to which the anti-vibration device 10 is fixed is
b, 3c are a main body 3b whose cross section is bent in an inverted U-shape.
M and 3cM are formed by welding and fixing flat bottom plates 3bB and 3cB to form a closed cross-sectional structure in which the inside is hollow. Further, through holes 6 through which the cylindrical body 11 of the vibration isolator 10 can be inserted are formed in the upper surface portions of the main body portions 3bM and 3cM, and four bolt insertion holes 7 are formed around the through holes 6. Is provided. Then, the bolt 19 is inserted into the bolt insertion hole 7 from the inside of the horizontal structural members 3b and 3c.
The vibration isolator 10 is fixed by screwing a nut 20 after projecting upward through the bolt insertion hole 18 a of the mounting plate 18. In this state, a through-hole is provided in the bottom plate 5a of the cab 5 and the through-hole is attached to the connecting member 15 and brought into contact with the receiving plate 17, and the nut 21 is screwed into the threaded portion of the connecting member 15. The driver's cab 5 is supported on the upper revolving structure 1 via the vibration isolator 10 by vibration isolation.

As described above, the driver's cab 5 is elastically supported by the structural body 1 via the elastic member 13 constituting the vibration isolator 10. Is moved up and down in the damping force generating chamber 14, and at this time, the working fluid flows to the upper and lower parts defined by the movable plate 16, but this working fluid has a high viscosity. In addition, since the flow path of the working fluid is restricted by the movable plate 16, the viscous resistance and the flow resistance exert a damping force against the vertical movement of the connecting member 15. 5 can be prevented from being transmitted as much as possible.

[0009]

As described above, the elastic member
13 plus damping with working fluid enclosed in its lower position
A force generating chamber 14 is provided, and the viscous resistance and flow of the working fluid
An anti-vibration device 10 having an extremely high vibration absorption capability using resistance
In order to support the driver's cab 5 on the structural body 1
In other words, the portion where the elastic member 13 is attached is located on the structure 1 side.
In view of the necessity of attachment, adopting the above-described mounting structure has the following disadvantages.

First, in the vibration isolator 10, the mounting plate 18 is fixed to the upper surface of the horizontal structural member, but the three horizontal mounting members provided between the main structural members 2a and 2b are provided. If the upper surfaces of the structural members 3a, 3b, 3c are not exactly on the same plane, the receiving plates 17 of the respective vibration isolators 10 will not be at the same height position, so that the cab 5 will be mounted in an inclined state. As a result, the loads received by the respective vibration damping devices 10 are not uniform, and there is a problem that smooth vibration damping support cannot be performed. Here, welding is performed in order to assemble the horizontal structural members 3b and 3c and to connect to the main structural member 2 after the can assembling.
It is extremely difficult to assemble such that all the horizontal structural members 3a to 3c are at exactly the same height position due to the welding strain and the like. Therefore, in practice, it is not possible to prevent variations in the height position of each vibration isolator 10.

Second, in order to mount the vibration isolator 10,
Since the through holes 6 are provided in the horizontal structural members 3b and 3c having a closed cross-sectional structure, even if the through holes 6 are covered by the mounting plate 18 of the vibration isolator 10, this portion is not necessarily completely completed. Can not be sealed. If this part cannot be sealed, rainwater or the like will enter the inside, causing rust. Of course, if rust-proof coating is performed, rust can be suppressed, but it is impossible to perform rust-proof coating on the inside of the horizontal structural members 3b and 3c having a closed cross-sectional structure.

Third, the horizontal structural member is, in the first place,
It is necessary to improve rigidity in order to prevent low-frequency shaking from the viewpoint of riding comfort and the like, so it has a closed cross-sectional structure, and it can be said that it is to attach a vibration isolator to such a structural member, Providing the through holes is not preferable because the rigidity and the strength are reduced accordingly.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to mount a plurality of vibration isolators so that the height positions thereof can be accurately adjusted to each other so as to obtain flatness. Another object of the present invention is to improve the rigidity and strength of a structural member to which the vibration isolator is mounted.

[0014]

Means for Solving the Problems] To achieve the above object, the present invention has only set by Zaisa plurality of extending in the longitudinal direction
At least two horizontal structural members having a closed cross section are provided between the main structural member side portions of the upper revolving structure so as to be stretched at an interval in the front-rear direction, and operation is performed on the horizontal structural members. a chamber a device for vibration damping support, the elastic member provided on the upper side, the lower side becomes the damping force generating chamber, the cab anti Fu支
Comprising a vibration damping device for lifting, a hole for inserting the damping force generating chamber of the vibration isolating apparatus, the elastic portion around the through hole
A mounting bracket provided at a position between the material and the damping force generating chamber, the mounting bracket being fixed to the mounting bracket, the mounting bracket being fixed to a side surface of the horizontal structural member by welding means.
The mounting bracket includes front and rear horizontal structural members.
The corner part connected to the structural member, and
On the front side for the front transverse members, and on the rear
The horizontal structural member is characterized in that it is fixed to the rear side surface.

[0015]

The horizontal structural member, together with the main structural member, constitutes the structure of the entire upper revolving structure. The rigidity is improved by adopting a closed sectional structure. An anti-vibration device for supporting the driver's cab in anti-vibration is provided on the lateral structural member.
Despite the driver's cab facing the top of the horizontal structural member,
An elastic member is provided on the upper side, and the lower side is
The mounting plate is connected to the part where the elastic member is provided.
Due to the use of a connected vibration isolator, the mounting
Consider that a through hole is required to insert the force generation chamber.
In consideration of this, the vibration isolators are mounted via mounting brackets instead of being directly mounted on the lateral structural members. Thereby, it is not necessary to provide a through hole in the horizontal structural member, and the strength and rigidity of the horizontal structural member can be improved. In addition, since no through-hole is provided, the hollow portion inside the horizontal structural member can be sealed, so that rainwater and the like do not enter, and the inner surface of the horizontal structural member does not need to be specially rustproofed. Will not rust.

It is not always possible to assemble all the horizontal structural members at the same height position due to distortion caused by welding when the horizontal structural members are assembled into the can or when the horizontal structural members are connected to the main structural member after the can is assembled. Absent. Even if the horizontal structural member is not assembled with high precision, the height position can be easily controlled by adjusting the fixing position of the mounting bracket to the horizontal structural member. Therefore, by mounting the mounting brackets strictly at the same height position, all the vibration damping devices can be at the same height position. As a result, the driver's cab is accurately mounted horizontally with respect to the structure.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings. The structure of the upper revolving structure of the vehicle is substantially the same as that shown in FIG. 4. Therefore, the same or equivalent members as those of FIG. Is omitted. Also, the same configuration as that shown in FIG. 6 is used for the configuration of the vibration isolator, and therefore, the same or equivalent members as those in FIG. 6 are denoted by the same reference numerals.

As shown in FIGS. 1 and 2, the horizontal structural member 3 of the upper revolving structure 1 is located below the cab 5 and overlaps the lower surface of the cab 5. In spite of this, the vibration isolator 10 is not directly mounted between the driver's cab 5 and the lateral structural members 3b, 3c having a closed cross-sectional structure, but the main bodies 3bM, 3cM.
Of the corner of the corner connected to the main structural member 2
A mounting bracket 30 is fixedly provided by welding means, and the vibration isolator 10 is mounted on the mounting bracket 30. Moreover, the two horizontal structural members 3b, 3c
Of the front horizontal structural member 3b,
On the side of the main body 3cM of the rear lateral structural member 3c.
On the rear side, mounting brackets 30 are provided respectively.
Fixed. As shown in FIG. 3, the mounting bracket 30 is attached to the mounting portion 30a on which the vibration isolator 10 is mounted, and is bent perpendicularly to the mounting portion 30a to be fixed to the horizontal structural members 3b and 3c by welding. The fixing portion 30b is provided. A reinforcing portion 30c is provided between the attachment portion 30a and the fixing portion 30b so as to bridge.

The mounting portion 30a of the mounting bracket 30
Is provided with a through hole 31 through which the cylindrical main body 11 of the vibration isolator 10 is inserted. Bolt insertion holes 32 are provided at four locations around the through hole 31. The bolt 19 is inserted from below the bolt insertion hole 32. To mount the vibration isolator 10, the cylindrical main body 11 of the vibration isolator 10 is inserted through the through hole 31 and attached. The plate 18 is brought into contact with the mounting portion 30, and the bolt 19 is projected upward from below in a state where the bolt insertion hole 18 a provided in the mounting plate 18 is aligned with the bolt insertion hole 32. It can be attached by screwing.

The present embodiment is constructed as described above, and the horizontal structural members 3b and 3c having a closed cross-sectional structure are provided.
Is not provided with a through hole for mounting the vibration isolator 10, so that the lateral structural members 3b and 3c can have sufficient rigidity and strength, and the function as the structural body 1 cannot be regretted. will be able to exhibit, in particular the improvement of rigidity, wearing the cab 5, when allowed to drive the vehicle, it becomes the cab 5 can be prevented from low frequency vibration occurs as much as possible, and the cab 5 Viscous resistance and flow resistance of working fluid
By using the vibration isolator 10 with extremely high vibration absorption capacity
Since it is supported by the structure 1, the ride comfort by the operator is extremely good . Also, the horizontal structural members 3b, 3c
Since it is possible to form a closed structure, there is no risk of rainwater or the like entering, and therefore, there is no possibility that rust will occur even if rustproof coating is not applied.

Since the mounting brackets 30 are fixed to the side surfaces of the horizontal structural members 3b and 3c by welding means, the cans of the horizontal structural members 3b and 3c are assembled.
After connection to the main structural member 2, the mounting bracket 30 can be welded. Therefore, since the fixing portion 30b of the mounting bracket 30 can be welded to an arbitrary position, the position of the mounting bracket 30 is adjusted so that the height positions of the receiving plates 17 in all the vibration isolators 10 are accurately adjusted. Welding can be performed in the state where it is done. As a result,
When the receiving plate 17 is placed on the bottom plate a of the driver's cab 5, the flatness can be accurately obtained without tilting. As a result, all the vibration isolators 10 can evenly support the load, and reliably exhibit a good vibration isolation function.

Here, the fixing portion 30 of the mounting bracket 30
b is set to a somewhat large surface, and welding is performed over the entire periphery of the edge portion, so that the mounting bracket 3
0 is firmly fixed to the horizontal structural members 3b and 3c. In addition, since the reinforcing portion 30c is provided to extend between the fixing portion 30b and the mounting portion 30a, the load does not deform the connecting portion of the mounting portion 30a to the fixing portion 30b. In addition, of the loads received by the entire structure 1, the load on the driver's cab 5 is not so large. Even if the mounting bracket 30 is fixed to the horizontal structural members 3b and 3c by welding in this manner, sufficient strength can be obtained. Hold. On the other hand, the transverse structural member 3 is required to have extremely high rigidity against torsion, bending, and the like as a member constituting the structure 1. It is necessary to have strength and rigidity enough to withstand a load ten times or more than the load for supporting the cab 5. Therefore, in order for the horizontal structural member 3 to sufficiently exhibit its function as a structure, The lateral structure member 3 is not provided with a through hole which leads to a decrease in strength, and the vibration isolator 10 for supporting the driver's cab 5 having a relatively light load is a mounting bracket fixed to the lateral structure member 3 by welding. By providing the structure 30, the structure 1 in the upper-part turning body can have an extremely rational structure.

In the above-described embodiment, the vibration isolator attached to the mounting bracket is configured to be fixed with four bolts, but it may be configured to be fixed with two large-diameter bolts. . Further, the vibration isolator is provided at six places on the three horizontal structural members, but may be provided at only four places depending on the load of the cab. Furthermore, since the horizontal structural member located at the forefront is not in a closed cross-sectional structure, the vibration isolator mounted on the horizontal structural member is provided with a through hole directly in the horizontal structural member, and is directly attached to the horizontal structural member. However, it may be configured such that a mounting bracket for mounting the vibration isolator is also provided on the horizontal structural member located at the forefront portion, and when the horizontal structural member itself has a closed cross-sectional structure, Then, the vibration isolator may be mounted on the mounting bracket.

[0024]

As described above, according to the present invention, the driver's cab is placed directly on the horizontal structural member despite the fact that the horizontal structural member having a closed sectional structure is disposed at the lower position of the driver's cab. Do not support , but on the side of the horizontal structural member
Attach the mounting bracket to the connection part to the structural member with welding means
Since the driver's cab is fixed to the lateral structural member via the mounting brackets in a vibration-proof manner, an elastic member is provided on the upper side as a vibration isolator, and the lower side is a damping force generation chamber, A mounting portion is formed at the portion where the elastic member is provided, and a vibration isolator having a remarkably high vertical vibration absorption function can be used. There is no need to drill through holes that can be connected, and the inside can be sealed, so that it is possible to reliably prevent the occurrence of rust due to rainwater intrusion, etc.
In addition, even if welding distortion occurs during the formation and assembly of the horizontal structural member, it does not affect the mounting position of the vibration isolator, so that the driver's cab can be reliably supported in a planar shape with vibration isolation.

[Brief description of the drawings]

FIG. 1 is a plan view of an cab anti-vibration support device according to an embodiment of the present invention.

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

FIG. 3 is an external view showing a configuration of a mounting bracket on which the vibration isolator is mounted.

FIG. 4 is a configuration explanatory view of an upper swing body of a hydraulic shovel as a construction machine.

FIG. 5 is a plan view of a conventional cab anti-vibration support device.

FIG. 6 is a sectional view taken along line YY of FIG. 5;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Structure 2, 2a, 2b Main structural member 3, 3a, 3b, 3c Horizontal structural member 5 Operator's cab 10 Vibration isolator 18 Mounting plate 18a Bolt insertion hole 19 Bolt 30 Mounting bracket 30a Mounting portion 30b Fixed portion 30c Reinforcement portion 31 Through hole 32 Bolt insertion hole

 ──────────────────────────────────────────────────の Continuing from the front page (72) Koji Tahara, Inventor 650, Kandate-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. (56) References JP-A-62-152982 (JP, A) JP-A-2-81283 (JP, U) JP-A-63-189886 (JP, U)

Claims (1)

(57) [Claims] 1. A were Zaisa plurality extending in the longitudinal direction set only upper
At least two horizontal structural members having a closed cross-sectional shape are provided between the main structural member side portions of the revolving structure so as to be stretched at an interval in the front-rear direction, and the driver's cab is supported on the horizontal structural members by vibration isolation. An elastic member is provided on an upper side, and a damping force generation chamber is provided on a lower side, and a vibration isolator for supporting the driver's cab in vibration isolation is provided. With holes,
Around the through hole, the space between the elastic member and the damping force generating chamber is provided.
A mounting bracket to which a mounting portion provided at a position is fixed, wherein the mounting bracket is welded to a side surface of the horizontal structural member.
In a one to fix the mounting bracket, the main structure before and after the horizontal structural members
The corner part connected to the member and forward
For the lateral structural members of
An cab vibration isolating support device for a hydraulic shovel, wherein the cab member is fixed to a rear side surface of each of the structural members .