JP3245242B2 - Working machine with cab - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a working machine with a cab provided in a working machine such as a hydraulic excavator.
TECHNICAL FIELD The present invention relates to a working machine with a cab configured to buffer vibration transmitted from a main body frame of the working machine to a cab .

[0002]

2. Description of the Related Art FIGS. 10 to 14 show a hydraulic shovel as an example of a conventional working machine with a cab.

In the figure, 1 is a lower traveling body, 2 is a turning device, 3
Denotes an upper revolving unit that is rotatably mounted on the lower traveling unit 1 via the revolving unit 2 and constitutes a working machine main body. The upper revolving unit 3 includes a revolving frame 4 as a main body frame forming a frame structure. A machine room 5 provided on the turning frame 4, a driving room main body 8, which is provided on the turning frame 4 at the front left side of the machine room 5, An operator's cab 6 including various operating levers and instruments provided, and a turning frame 4 located at the rear side of the machine room 5.
And a counterweight 7 provided at the rear of the upper revolving unit 3 with respect to a working device 17 described later.

[0004] Reference numeral 8 denotes an operator's cab main body which is disposed on the revolving frame 4 and constitutes a main body of the operator's cab 6. As shown in FIG. 11, the operator's cab main body 8 is formed by pressing a thin steel plate. By welding, a rectangular ceiling portion 8A extending in the front-rear direction, a substantially V-shaped front portion 8B having a vertically intermediate portion protruding forward, and a substantially vertical surface with respect to the revolving frame 4 are formed. Left and right side portions 8 of a substantially pentagonal shape provided with portions that protrude forward according to the shapes of the vertically elongated rear surface portion 8C and the shapes of the rear surface portion 8C and the front surface portion 8B.
D, 8D (only one is shown) and the like are formed as a box-shaped cab box. The cab body 8
A door 9 is provided on the left side surface portion 8D of the driver's cab main body 8 via a floor panel bracket 8E on the lower surface side of the cab main body 8.
Is attached.

Reference numerals 11, 11,... Denote lower buffer supports which elastically support the cab body 8 on the revolving frame 4, and the lower buffer supports 11 are, as shown in FIGS. Anti-vibration rubber 12, spacer 13, and each stopper 14
And so on. And each lower buffer support 1
1 is provided between the floor panel 10 of the cab body 8 and the turning frame 4, and a total of four (only two of them are shown) are separated from each other in front, rear, left, and right. 8 to be attenuated.

Reference numerals 12 and 12 denote anti-vibration rubbers. Each of the anti-vibration rubbers 12 is formed in a short and thick cylindrical shape using an elastic material such as synthetic rubber, and has a central portion in the axial direction as shown in FIG. An insertion hole 12A is formed. And
Each of the anti-vibration rubbers 12 is disposed so as to be coaxial with a mounting hole 4B formed in the upper surface 4A of the revolving frame 4, and sandwiches the upper surface 4A of the revolving frame 4 from above and below.

Reference numeral 13 denotes a spacer made of a metal cylinder having a bolt insertion hole 13A in the axial direction.
Reference numeral 3 denotes an intermediate portion in the longitudinal direction, which is loosely fitted in the mounting hole 4B of the revolving frame 4, and the upper and lower ends of which are the insertion holes 12 of the respective vibration-proof rubbers 12.
A is fitted inside. In addition, the upper and lower end surfaces of the spacer 13 are in contact with a bottom portion 14B of each stopper 14 described later.

Numerals 14 and 14 denote stoppers formed into a bottomed cylindrical shape by press-forming a metal plate or the like. As shown in FIG. A bottom portion 14B formed in a shape and having a bolt insertion hole 14A formed in the center, and a cylindrical portion extending in the axial direction from an outer peripheral side of the bottom portion 14B and having a shorter length than the vibration-proof rubber 12. 14C, and the tip side of the cylindrical portion 14C is an opening 14D. The stoppers 14 are attached to each other so that the openings 14D face each other with the upper surface 4A of the revolving frame 4 interposed therebetween through the respective rubber cushions 12, and cover the upper and lower rubber cushions 12 from outside. Have been.

Reference numerals 15, 15,... Denote bolts. The bolts 15 are inserted into the bolt insertion holes 8F of the floor panel bracket 8E from the inside of the cab body 8, and the bolt insertion holes 13A of the spacers 13 and the floor plate. 10 bolt insertion holes 10A,
The inside of each mounting hole 4B of the upper surface portion 4A of the revolving frame 4 extends, and the lower side of the lower buffer support 11, that is, the stopper 14
The operator's cab main body 8 is positioned on the revolving frame 4 by screwing and tightening the nut 16 from below the bottom portion 14B.

Reference numeral 17 denotes a working device provided at a front portion of the upper revolving unit 3, and the working device 17 is provided on a highly rigid bracket portion 4C forming a part of the revolving frame 4 so as to be capable of elevating and lowering. 17A, an arm 17B provided at the tip of the boom 17A so as to be able to move up and down, and a backhoe type bucket 17 provided rotatably at the tip of the arm 17B.
C, these booms 17A, arms 17B,
The bucket 17C is operated by a boom cylinder 17D, an arm cylinder 17E, and a bucket cylinder 17F. The work apparatus 17 rotates the bucket 17C by the bucket cylinder 17F while raising and lowering the boom 17A and the arm 17B by the boom cylinder 17D and the arm cylinder 17E during the excavation work of the earth and sand. Is to be excavated.

In the hydraulic excavator thus configured,
A prime mover and a hydraulic pump (both not shown) driven by the prime mover are provided in a machine room 5 of the upper swing body 3, and hydraulic oil discharged from the hydraulic pump is supplied to the traveling hydraulic motor of the lower traveling body 1 ( By supplying / discharging the cylinders 17D, 17E, 17F, etc. of the working device 17 and the like, these are actuated to drive the vehicle and perform excavation work such as earth and sand.

The lower shock-absorbing supports 11 provided between the floor plate 10 of the cab body 8 and the revolving frame 4 receive vibrations from the engine, vibrations during traveling, and vibrations due to excavation reaction force during work. The transmission from the revolving frame 4 to the driver's cab main body 8 is buffered by the respective vibration isolating rubbers 12 so that the vibration and noise at this time are reduced so that the riding comfort of the driver's cab 6 is not deteriorated.

As shown in FIG. 12, each lower buffer support 11 has an opening 14D of each stopper 14 with respect to the upper surface 4A of the revolving frame 4, for example, a gap S of about 2 to 3 mm.
The cab main body 8 is restricted from rolling (rolling) in the left and right directions beyond the gap S, whereby the cab main body 8 is attached to peripheral members such as the boom cylinder 17D. It is designed to prevent collision and damage accidents.

[0014]

In the prior art described above, for example, four lower buffer supports 11, 11, and 4 are provided between the upper surface 4A of the turning frame 4 and the floor plate 10 of the cab body 8. Are arranged to prevent the transmission of vibrations from the outside to the operator's cab 6, but in practice, the following problems based on the natural frequency occur.

That is, assuming that the weight W of the cab 6, the total spring constant k of each lower buffer support 11, and the gravitational acceleration G, the natural frequency f of the cab 6 in the vertical direction is

[0016]

(Equation 1) Is represented by

Here, the operator's cab body 8 is approximated by a one-degree-of-freedom vibration model as shown in FIG.
When the forced vibration a0 cosωt is applied in the vertical direction, and the amplitude of the vibration transmitted to the cab 6 is a, the vibration transmission rate τ is

[0018]

(Equation 2) η: Frequency ratio ζ: Damping ratio ωn: Natural angular frequency C: Damping coefficient Cc: Critical damping coefficient

At this time, the relationship between the frequency ratio η and the vibration transmissibility τ is represented by the characteristic line shown in FIG.
Before and after, vibration increases due to resonance, and the frequency ratio η
It can be understood that the larger the value becomes, the smaller the vibration transmissibility τ becomes 1 and the less the vibration is transmitted.

The weight W of the entire cab 6 is 400 to 400.
500 kg, total spring constant k of each lower buffer support 11
Under the condition of 2000 to 8000 kg / cm,
Therefore, the natural frequency f of the cab 6 is about 20 to 45 Hz.

However, the vibration of about 20 to 45 Hz is largely included in the vibration during the operation of the hydraulic shovel, and when the natural frequency f of the cab 6 is in the above range, the frequency ratio η approaches η = 1. In addition, there is a problem that the vibration transmissibility τ is increased and the ride comfort of the driver's cab 6 is deteriorated.

On the other hand, if the spring constant k of each lower buffer support 11 is reduced in order to lower the natural frequency f, the vibration in the vertical direction can be attenuated, but the turning center OO of the turning frame 4 (see FIG. 10). ), The pitching of the cab 6 vibrating in the front-rear direction and the rolling of the cab 6 vibrating in the left-right direction are increased, and the ride comfort is deteriorated.

When the pitching or rolling becomes large, the cab body 8 is
D and the like, causing a breakage accident, as shown in FIG. 12, the gap S between the opening 14D of each stopper 14 and the upper surface 4A of the revolving frame 4 is set to, for example, 2 to 2.
When the driver's cab main body 8 vibrates beyond the gap S, the opening 14D of each stopper 14 collides with the upper surface 4A of the turning frame 4, and the turning frame 4
Therefore, there is a problem that the vibration from the vehicle is directly transmitted to the driver's cab main body 8 and the riding comfort of the driver's cab 6 becomes very poor.

The present invention has been made in view of the above-mentioned problems of the prior art, and the present invention can effectively prevent the cab main body from vibrating forward, backward, left, and right to cause pitching and rolling. In addition, an object of the present invention is to provide a working machine with a driver's cab that can effectively attenuate vertical vibrations and improve riding comfort.

[0025]

To solve the problems described above SUMMARY OF THE INVENTION, the inventions of claim 1, a body frame of the working machine,
A box-shaped cab main body provided on the main body frame and provided with a floor plate on the lower surface side, and a plurality of cab main bodies are provided between the floor plate of the cab main body and the main body frame, and vibration from the main body frame is provided. In a working machine with a cab comprising a lower buffer support for buffering transmission to the cab main body, the cab main body extends vertically on the main body frame between the floor plate of the cab main body and the main body frame. A parallel link mechanism that allows vibration and restricts horizontal vibration is provided, and the parallel link mechanism includes at least one or more torsion bar , and the torsion bar is provided in front of the cab body.
A pair of link locks that extend rearward and are
And a connecting rod connecting the link rods in the left-right direction.
And both ends of the torsion bar in the front-rear direction.
Are respectively provided on the floor plate and the body frame of the cab body.
It is characterized in that it is configured to be rotatably connected .

[0026] According to the invention of claim 2, wherein the parallel link mechanism, the front and Quito Shonba, the cab body spaced in the longitudinal direction of the cab body from the torsion bar
It is composed of a rotatably provided link bars between the floor plate and the body frame.

[0027] The feature of the configuration adopted by the invention of claim 3 is as follows.
The sign is between the floor panel of the cab body and the body frame.
The cab body vibrates up and down on the body frame
Parallel link that allows for horizontal vibration
The mechanism is provided, said parallel link mechanism includes a first spaced apart longitudinally between the floor plate and the body frame of the cab body, constituted by a second torsion bar, said first, second preparative <br /> Shonba each extend in the longitudinal direction of the cab body, consists of a pair of link rods spaced in the lateral direction, a connecting rod coupled between the respective link rods on the left and right direction, the first, second the longitudinal direction end side of the second torsion bars are configured to respectively pivotally connected to the floor plate and the body frame of the cab body.

The invention according to claim 4 is characterized in that the first and the second
The torsion bar extends in the front-back direction of the cab body,
Provide connecting links that are pin-coupled to the connecting rods on both ends so that the connecting rods rotate integrally.
It has a configuration .

Furthermore, according to the invention of claim 5, wherein each of the lower cushioning support is composed of a coil spring and a shock absorber to cushion with a relatively small spring constant vibration of the cab body.

[0030]

[Action] With this configuration, a first aspect of the invention, the parallel link mechanism configured to include at least a torsion bar
Therefore, the cab body horizontally, for example, can convert to oscillate back and forth direction to vertical vibration, can be reduced regulate horizontal vibrations Rutotomoni, cab body pin production kitchen Guth in the longitudinal direction Can be reliably reduced. This place
If the torsion bar is connected to a pair of link rods
And the both ends of the torsion bar in the front-rear direction
The cab body is pivotally connected to the floor panel and body frame.
By doing, for example, from the body frame to the cab body
The torsional vibration is transmitted to the torsion bar
High spring constant against torsional force
To the bar, for example,
The driver's cab body is torsionally vibrated from the body frame
Rolling in the left and right direction
It can be regulated by elasticity.

The invention according to claim 2 is a parallel link mechanism.
Driving by the torsion bar and link rod
The upper and lower sides of the chamber body vibrate horizontally, for example,
Can be converted to vibration in the horizontal direction
The driver's cab can be pitched forward and backward
Can be reliably reduced.

According to the third aspect of the present invention, since the parallel link mechanism is constituted by the first and second torsion bars spaced apart in the front-rear direction of the cab body, the first and second torsion bars are provided . This makes it possible to restrict the cab main body from pitching in the front-rear direction or rolling in the left-right direction with a high spring constant.

According to a fourth aspect of the present invention, the connecting rods of the first and second torsion bars are connected by a connecting link extending in the front-rear direction between the floor plate of the cab main body and the main body frame.
As a result , the first and second torsion bars can be reliably prevented from rotating in opposite directions, and the cab main body can be prevented from tilting forward and backward with respect to the main body frame.

Further, according to the fifth aspect of the present invention, since each of the lower buffer supports is composed of a coil spring and a shock absorber, the vibration in the vertical direction of the cab main body can be buffered with a small spring constant, and the entire cab is provided. , The vertical vibration transmitted to the cab body can be satisfactorily attenuated.

[0035]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In the embodiments, the same components as those of the above-described conventional technology are denoted by the same reference numerals, and description thereof will be omitted.

FIGS. 1 to 3 show a first embodiment of the present invention.

In the figure, reference numeral 21 denotes a revolving frame which constitutes a main body frame of the upper revolving unit 3. The revolving frame 21 is substantially the same as the revolving frame 4 described in the related art, Is a central portion thereof attached to the turning device 2 (a portion near the turning center OO).
Are formed as thick high-rigidity portions 21A having high rigidity (see FIGS. 2 and 3). The turning frame 21 is integrally provided with a support portion 21B, which is located on the front left side of the high rigidity portion 21A and supports a driver's cab body 22 described below from below, and the support portion 21B is a high rigidity portion 21A. It is formed with lower rigidity. In addition, the high rigidity portion 21A
A pair of left and right bracket portions 21C, 21C
The boom 17A of the working device 17 and the boom cylinders 17D are pin-connected to the bracket portions 21C.

Reference numeral 22 denotes an operator's cab main body provided on the revolving frame 21. The operator's cab main body 22 is almost the same as the operator's cab main body 8 of the operator's cab 6 described in the prior art, and has a ceiling portion 22A,
Front part 22B, rear part 22C and left and right side parts 22
D, 22D, and a door 23 is provided on the left side surface portion 22D. On the lower surface side of the cab main body 22, a floor plate 24 forming a part of the cab main body 22 is provided, and the floor plate 24 is provided on the high rigid portion 21A and the support portion 21B of the revolving frame 21 in the lower portion described later. The entire cab 6 is supported via the buffer support 25.

Reference numerals 25, 25,... Denote lower buffer supports provided between the turning frame 21 and the floor plate 24 of the cab body 22, and each lower buffer support 25 is
Each of the shock absorbers 26 is disposed between the support portion 21B (high rigidity portion 21A) and the floor plate 24 of the cab body 22 in front, rear, left and right. Each of the coil springs 27 is integrally provided and constantly urges each of the shock absorbers 26 in the extension direction, and each of the coil springs 27 is formed with a relatively small spring constant.

Here, of the lower buffer supports 25,
The lower right buffer support 25 on the rear right side is disposed on the high rigidity portion 21A of the revolving frame 21 as shown in FIG. 3, and the other lower buffer supports 25 are disposed on the support 21B. Each of the shock absorbers 26 is provided with a damping force generating portion 26A which protrudes above the floor plate 24 of the cab body 22.
Each of the damping force generators 26A is configured to attenuate the cab body 22 when the cab body 22 vibrates vertically.

Reference numerals 28, 28,... Denote stoppers provided between the turning frame 21 and the floor plate 24 of the cab main body 22 in parallel with the respective lower buffer supports 25, and the respective stoppers 28 correspond to the respective shock absorbers 26. And the shock absorber 26 is controlled by the coil spring 27
It also prevents excessive stretching and contraction. The stoppers 28 prevent the cab main body 22 from vibrating beyond the stroke end of each shock absorber 26 when a large impact or the like is applied to the cab 6 from the outside.

Numerals 29, 29 denote mounting brackets which are erected downward from the lower surface of the floor plate 24, and each of the mounting brackets 29 is formed by bending substantially U-shaped as shown in FIG.
Around the center of the floor plate 24, it is fixed to the left and right sides by means of welding or the like, and protrudes toward the revolving frame 21 with a predetermined height. Reference numerals 30 and 30 denote other mounting brackets fixed to the support portion 21B of the revolving frame 21, and the mounting brackets 30 are provided in front of the mounting brackets 29 and farther to the left and right than the mounting brackets 29, respectively. It protrudes upward from the portion 21B with a predetermined height.

Numeral 31 denotes a turning frame 21 and a cab main body 22.
And a torsion bar 31 rotatably connected to the floor plate 24 of the driver's cab via mounting brackets 29 and 30. The torsion bar 31 moves between the floor plate 24 of the cab body 22 and the turning frame 21 in the front-rear direction. And a pair of link rods 32,
And a connecting rod 33 connecting the link rods 32 in the left-right direction to form a substantially U-shape. 30 is rotatably mounted.

The torsion bar 31 is provided such that the tip end of each link rod 32 is attached to each mounting bracket 2 on the floor plate 24 side.
9 is rotatably connected to a pin. The torsion bar 31 has a high spring constant with respect to a torsional force between each link rod 32 and the connecting rod 33, and the torsional vibration from the turning frame 21 causes the cab body 22 to roll in the left-right direction. Is effectively regulated.

Reference numeral 34 denotes a mounting bracket projecting downward from the lower surface of the floor plate 24 of the cab body 22, and the mounting bracket 34 has a cross section substantially similar to the mounting bracket 29 as shown in FIG. The mounting bracket 34 is U-shaped, and the mounting bracket 34 is a mounting bracket 2 on the bracket portion 21C side.
One is provided on the floor plate 24 at a predetermined distance behind the rear panel 9.

Reference numeral 35 denotes a high rigidity portion 21A of the revolving frame 21.
5 shows a mounting bracket projecting upward from the upper side surface of the mounting bracket 35. The mounting bracket 35 is formed of two plates facing in parallel, and is located at the front side of the mounting bracket 34, and is located between the mounting bracket 34 and the front and rear sides. High rigid portion 21 so as to face each other
A.

Reference numeral 36 denotes a link rod rotatably provided by connecting both ends between the mounting brackets 34 and 35 by pins, and the link rod 36 is separated rearward from the torsion bar 31 so as to be separated from the torsion bar 31. A parallel link mechanism is constituted with the 31 link rods 32.

The hydraulic excavator according to the present embodiment has the above-described configuration, and its basic operation is not particularly different from that of the prior art.

However, in the present embodiment, the turning frame 21
Each of the lower shock-absorbing supports 25 for supporting the driver's cab main body 22 via the floor plate 24 on the support portion 21B or the like is constituted by a shock absorber 26 and a coil spring 27, and the shock absorber 26 and the coil spring 27 The contraction is restricted by a stopper 28, and a pair of link rods 32, 32 extending in the front-rear direction and between the respective support portions 21 </ b> B of the revolving frame 21 and the floor plate 24 of the cab body 22 are provided. A torsion bar 31 composed of a connecting rod 33 integrally connected in the left-right direction with its base end side rotatably connected via mounting brackets 29 and 30, and a mounting bracket provided on the floor plate 24 side of the cab body 22. Reference numeral 34 denotes the high rigidity portion 2 of the revolving frame 21.
Link rod 3 between the mounting bracket 35 provided on
6 are rotatably connected, and the link bar 36 and each link rod 32 of the torsion bar 31 constitute a parallel link mechanism, so that the following operational effects can be obtained.

First, the revolving frame 21 has a high rigidity portion 21A.
The turning frame 21 is mounted on the lower traveling body 1 in the vicinity of the turning center OO so as to be able to turn via the turning device 2 and supports the cab main body 22 via each lower buffer support 25 and the like. Since the support portion 21B has a cantilever structure with respect to the high rigidity portion 21A, the revolving frame 21 not only vibrates in the vertical direction due to vibration during traveling or vibration due to excavation reaction force during work, etc. The bearing portion 21B separated from the high-rigidity portion 21A may torsionally vibrate with respect to the high-rigidity portion 21A in the direction of arrow A in FIG.
In this case, the support portion 21B of the turning frame 21 is used.
1 vibrates in the direction of arrow B in FIG. 1 in the front-rear direction, causing the cab body 22 to pitch, and in the left-right direction, vibrates in the direction of arrow C in FIG.

However, the cab main body 22 has the floor plate 24 connected to the support portion 21B of the revolving frame 21 via the torsion bar 31, and the torsion bar 31 is connected to the left and right link rods 32, 32 and the respective link rods 32. It is formed in a substantially U-shape from the connecting rod 33 that connects between the connecting rod 33 and the connecting rod 33 and each link rod 32 so as to support with a high spring constant against torsional force. Even if the support portion 21B supporting the torsion vibrates in the direction of arrow C in FIG. 2, the link rods 32 of the torsion bar 31 will swing in opposite directions via the connecting rod 33 at this time. The rod 33 opposes the torsional force at this time with a high spring force, and the torsion bar 3 prevents the cab body 22 from rolling in the left-right direction.
1, the vibration transmitted to the driver's cab main body 22 can be effectively buffered by each lower buffer support 25.
Thereby, the vibration of the driver's cab main body 22 in the left-right direction can be restricted to a small extent. For safety such as the side surface portion 22D of the driver's cab main body 22 colliding with a surrounding member such as the boom cylinder 17D,
Strength problems can be reliably solved.

The link rod 32 of the torsion bar 31 constitutes a parallel link mechanism together with the link rod 36 as shown in FIGS. 1 and 3, so that the support portion 21B of the revolving frame 21 is shown by an arrow B in FIG. Even in the case of vibration in the direction, the vibration of the cab body 22 in the front-rear direction can be converted into vibration in the up-down direction, and the pitching of the cab body 22 in the front-rear direction can be reliably suppressed.

Further, each lower buffer support 25 supporting the cab body 22 via the floor plate 24 on the revolving frame 21.
Is composed of a shock absorber 26 and a coil spring 27, and the vertical vibration of the cab body 22 can be buffered with a small spring constant, so that the natural frequency of the entire cab 6 is more reliably compared with that of the prior art. The vertical vibration transmitted to the cab body 22 can be effectively attenuated.

Therefore, according to the present embodiment, the cab body 2
2 can be reliably prevented from pitching in the front-rear direction or rolling in the left-right direction due to the torsional vibration of the revolving frame 21 by the parallel link mechanism including the combination of the torsion bar 31 and the link rod 36, and the operator's cab Body 2
The safety and strength problems such as the collision of the second member 2 with the surrounding members can be solved. By using a combination of the shock absorber 26 and the coil spring 27 as each lower cushioning support 25, the natural frequency of the entire driver's cab 6 can be reduced and the vertical vibration can be effectively attenuated. Comfort can be greatly improved.

FIGS. 4 to 6 show a second embodiment of the present invention. The feature of this embodiment is that a parallel link mechanism provided between the floor plate of the cab body and the turning frame is provided by the first and second embodiments. Second
In that it consists of a torsion bar. In addition,
In this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the figure, reference numerals 41, 41,... Denote mounting brackets provided on the lower surface of the floor plate 24. The mounting brackets 41 are formed from the floor plate 24 in substantially the same manner as the mounting bracket 29 described in the first embodiment. although provided to project in a substantially U-shape to the revolving frame 21 side, the respective mounting brackets 41 in the lateral direction and the longitudinal direction intermediate portion and the rear side of the floor plate 24 with a smaller projecting size than the respective mounting bracket 29 A total of four pairs are provided separately from each other.

Reference numerals 42, 42,... Denote other mounting brackets.
As shown in FIG. 6, it is fixed to the upper surface of the obstruction portion 21B and the high rigidity portion 21A of the revolving frame 21 farther to the left and right than 1 as shown in FIG.

Reference numeral 43 denotes a first torsion bar. The torsion bar 43 is provided between the turning frame 21 and the cab body 22.
Is rotatably attached to the floor plate 24 via the mounting brackets 41 and 42, and constitutes a parallel link mechanism together with a second torsion bar 46 described later. Here, the torsion bar 43 extends in the front-rear direction, and is fixed to a pair of link rods 44, 44 spaced apart in the left-right direction at the base end of each link rod 44.
The connecting rod 45 is formed in a substantially U-shape from a connecting rod 45 connecting the four in the left-right direction, and both ends in the axial direction of the connecting rod 45 are rotatably attached to the revolving frame 21 via the mounting brackets 42 on the front side. ing. Also, the torsion bar 4
The link rods 3 extend obliquely upward as shown in the figure, and the tip ends of the link rods 44 are rotatably mounted on the floor plate 24 via the mounting brackets 41 on the front side. The torsion bar 43 has a high spring constant with respect to the torsional force of the connecting rod 45 connecting the link rods 44,
A relatively strong spring force is generated when the link rods 44 swing in opposite directions.

Reference numeral 46 denotes a second torsion bar which constitutes a parallel link mechanism together with the first torsion bar 43;
The torsion bar 46 is connected to the first torsion bar 43.
In substantially the same manner as described above, a pair of link rods 47, 47 extending in the front-rear direction and separated in the left-right direction, and a connecting rod 48 connecting the link rods 47 in the left-right direction at the base end side of each link rod 47. The connecting rod 4 is formed in a
8 are rotatably mounted on the revolving frame 21 via respective mounting brackets 42 on the rear side. As shown in FIG. 4, the torsion bar 46 extends obliquely upward so that each link rod 47 forms a parallel link together with each of the link rods 44. The pins are rotatably connected via pins. The torsion bar 46 has a high spring constant with respect to the torsional force of the connecting rod 48 between the link rods 47, and the torsion bar 46 together with the torsion bar 43 is subjected to torsional vibration from the turning frame 21. The rolling of the cab body 22 in the left-right direction is restricted with a high spring force.

Then, each of the first and second torsion bars 4
As shown in FIG. 4, each of the link rods 4 and 3 has a smaller height dimension of each of the mounting brackets 41 and 42.
4 and 47 constitute a parallel link mechanism in a state of being inclined in the front-rear direction, and each link rod 4 is formed based on the state shown in FIG.
4, 47 are rotated to convert the vibration in the front-back direction into the vibration in the up-down direction.

According to the present embodiment having the above-described structure, substantially the same operation and effect as those of the first embodiment can be obtained. However, in the present embodiment, particularly, between the turning frame 21 and the floor plate 24 of the cab body 22, A first torsion bar 43 comprising a pair of link rods 44 extending in the front-rear direction, and a connecting rod 45 integrally connecting the base ends of the link rods 44 in the left-right direction; 4
3 and a second torsion bar 46 comprising a pair of link rods 47, 47 extending in the front-rear direction and connecting rods 48 integrally connecting the base ends of the link rods 47 in the left-right direction. The link rods 44, 47 of the first and second torsion bars 43, 46 are rotated while forming the parallel link mechanism in a state where the link rods 44, 47 are inclined in the front-rear direction of the cab body 22. Therefore, the front of the cab main body 22 than the first embodiment,
The rear can be evenly supported with a larger spring force, and the cab main body 22 can be prevented from relatively leaning back and forth on the turning frame 21.

For example, when the torsional vibration is transmitted to the torsion bars 43 and 46 by transmitting the torsional vibration in the right and left directions from the turning frame 21 to the cab main body 22, the torsion bars 43 and 46 have a large spring constant with respect to the torsional force. Can be regulated,
Rolling of the driver's cab body 22 in the left-right direction can be effectively reduced. Also, work on sloping ground and bucket 17C
The cab main body 22 can be effectively prevented from tilting and vibrating even when a large excavation reaction force is generated in the front-rear direction generated when the soil is scooped up.

FIGS. 7 to 9 show a third embodiment of the present invention. The feature of this embodiment is that the connecting rods of the first and second torsion bars are linked to each other by a link. The configuration is such that each connecting rod is integrally rotated by the connecting link at the time of vibration. In this embodiment, the same components as those in the second embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

In the figure, reference numerals 51, 51,... Denote mounting brackets provided on the lower surface side of the floor plate 24. The mounting bracket 51 is substantially the same as the mounting bracket 41 described in the second embodiment. Each of the mounting brackets 51 protrudes in a substantially U-shape toward the revolving frame 21 from FIG.
As shown in FIG. 9, each of the lower cushion supports 25 is provided at the four corners of the floor plate 24 and is largely separated in the front-rear direction and extends toward the revolving frame 21. Further, link rods 56 and 60 to be described later are rotatably connected to the respective mounting brackets 51 via cylindrical rubber bushings 52 and pins 53.

Reference numerals 54, 54 denote other mounting brackets provided on the revolving frame 21 side.
Reference numeral 4 is fixed to the upper surface of the support portion 21B and the high-rigidity portion 21A of the revolving frame 21 so as to be located outside the mounting brackets 51 in the left-right direction and behind the mounting brackets 51.

Reference numeral 55 denotes a first torsion bar. The torsion bar 55 is rotatably mounted between the revolving frame 21 and the floor plate 24 via the mounting brackets 51 and 54, and a second torsion bar to be described later. And a torsion bar 59 constitute a parallel link mechanism. The torsion bar 55 includes a pair of link rods 56, 56 in substantially the same manner as the torsion bar 43 described in the second embodiment.
A torsion bar 5 having a connecting rod 57
5 is such that each link rod 56 is attached to each of the mounting brackets 51,
A pair of bracket portions 58, 58, which are formed to be short corresponding to the distance between them and are opposed to each other via a predetermined interval at the center of the connecting rod 57, are provided integrally with the floor plate 24 side.

Reference numeral 59 denotes a second torsion bar. The torsion bar 59 is provided between the revolving frame 21 and the floor plate 24 via the mounting brackets 51 and 54 in substantially the same manner as the first torsion bar 55. The torsion bar 59 is rotatably mounted between the revolving frame 21 and the floor plate 24 via the mounting brackets 51 and 54 in substantially the same manner as the first torsion bar 55. The torsion bar 59 is substantially the same as the first torsion bar 55, and has a pair of link rods 60,
60, a connecting rod 61 and a pair of bracket portions 62,
62. The torsion bar 59 together with the first torsion bar 55 restricts the cab body 22 from rolling in the left-right direction due to torsional vibration from the turning frame 21 with a high spring constant spring force. .

Reference numeral 63 denotes a connecting link provided between the connecting rods 57 and 61 constituting the first and second torsion bars. The connecting link 63 extends between the connecting rods 57 and 61 in the front-rear direction. The front end side is pin-connected between the bracket portions 58 of the torsion bar 55. The connecting link 63 has its rear end side pin-connected between the bracket portions 62 of the torsion bar 59, and has connecting rods 57, 61.
Are always rotated integrally.

When the cab main body 22 vibrates forward and backward, the connecting rod 57 of the torsion bar 55 is moved.
Is rotated with respect to each mounting bracket 54, the rotation of the connecting rod 57 is transmitted to the connecting rod 61 of the torsion bar 59 via the connecting link 63, so that the connecting rod 5
7 and 61 are reliably restricted from rotating in opposite directions, and the connecting link 63 can restrict the driver's cab body 22 from tilting in the front-rear direction with respect to the turning frame 21.

According to the present embodiment having the above-described structure, the same operation and effect as those of the second embodiment can be obtained. However, in this embodiment, particularly, the connection between the connecting rods 57, 61 of the torsion bars 55, 59 is performed. Since the link 63 is pin-connected, the connecting link 63 can more reliably restrict the cab main body 22 from tilting or vibrating in the front-rear direction.

The torsion bars 55 and 59 shorten the link rods 56 and 60, respectively.
Since the cab body 22 vibrates in the left-right direction when the cab body 22 vibrates in the left-right direction, the link rods of the torsion bars 55, 59 are connected to each other between the mounting brackets 51, 60 and the mounting brackets 51 via the pins 53 via the cylindrical rubber bushes 52. The torsional moment acting on the connecting rods 57, 61 from 56, 60 can be reduced,
The cab main body 22 can be supported in a stable posture as well as supported by a torsion spring having a large spring constant. And since the turning radius of each link rod 56, 60 can be reduced,
While the floorboard 24 can be prevented from tilting greatly,
Due to the elastic deformation of the rubber bush 52 provided between each of the mounting brackets 51 and each of the link rods 56 and 60, transmission of high-frequency vibration from the turning frame 21 to the cab body 21 can be effectively attenuated. Further, the connecting rod 5 of the first and second torsion bars 55, 59
By connecting the connecting link 63 between the pins 7 and 61 by pins, the link rods 56 and 6 of the torsion bars 55 and 59 are connected.
0 can be rotated synchronously before and after the cab main body 22, and when the cab main body 22 vibrates, the parallelism of each link rod is broken and the cab main body can be prevented from being largely inclined. .

In each of the above embodiments, the torsion bar 31 (43, 46, 55, 59) is connected to the pair of link rods 32, 32 (44, 44, 47, 47, 56, 56, 6).
0, 60) and the connecting rod 33 (45, 48, 57, 6).
1) was described as being formed into a substantially U-shape from
Alternatively, for example, the torsion bar may be formed in a substantially “H” shape in which a longitudinal middle portion of each link rod is connected by a connecting rod in the left-right direction. In this case, one end of each link rod To the high rigid portion 21 of the revolving frame 21
The other end of each link rod may be rotatably connected to the floor plate 24 of the cab body 22 to the bearing A or the bearing 21B.

In each of the above embodiments, each lower buffer support 25 is connected to the shock absorber 26 and the coil spring 2.
7, the present invention is not limited to this. For example, a lower buffer support 11 made of a vibration-proof rubber 12 shown in FIG. 12 described in the related art may be used. In this case, the gap S shown in FIG. 12 may be increased to about 5 to 30 mm, and the spring constant of the vibration isolating rubber 12 or the like may be set small.

Further, in each of the above embodiments, the description has been made by taking the hydraulic excavator as an example. However, the present invention is not limited to this, and may be applied to, for example, a working machine such as a wheel type hydraulic excavator or a hydraulic crane having an operator cab. it can.

[0075]

As detailed above, according to the present invention, according to the calling <br/> light according to claim 1, between the floor plate and the body frame of the cab body, the cab body vertical direction on the body frame Provide a parallel link mechanism that allows to vibrate in the horizontal direction, restricts the vibration in the horizontal direction, the parallel link mechanism includes at least one torsion bar , and the torsion bar,
The cab body extends in the front-back direction and is separated in the left-right direction.
Left and right between the pair of link rods
And connecting rods connected in two directions.
The end side is moved to the floor plate and the body frame of the cab body.
Since it is configured to be rotatably connected to each other, the vibration of the cab body in the horizontal direction (front and rear direction and left and right direction) is converted into the vibration in the up and down direction, so that the vibration in the horizontal direction can be suppressed small, Rolling and pitching of the cab body can be reliably reduced. High spring constant against torsional force
Can be given to the torsion bar,
The driver's cab rolled left and right due to the torsional vibration
Can be regulated by the elasticity of the torsion bar.

Further, the invention according to claim 2 provides a parallel phosphorus
The lock mechanism is composed of a torsion bar and a link rod,
The link rod of the link rod of the torsion bar, by adopting a configuration in which spaced in the longitudinal direction of one link rod to luck Tenshitsu body, can give a high spring constant for twisting force to the torsion bar In addition, rolling of the driver's cab body in the left-right direction due to torsional vibration from the body frame can be effectively restricted by the elasticity of the torsion bar.

According to a third aspect of the present invention, the parallel link mechanism is constituted by first and second torsion bars.
Therefore, the first and second torsion bars allow the floor panel of the cab main body to be moved forward and backward with respect to the main body frame.
Left, equally in the right and could rotatably connected or pitching direction cab body back and forth can prevent with great spring force to or rolling in the lateral direction. Ma
And, the invention according to claim 4, linked by a connecting link extending the connecting rod of each torsion bar in the longitudinal direction
Are therefore, twisting can also be held in a stable posture cab body to vibration or the like, can be cab body before reliably prevented from tilting after.

[0078] Further, an invention according to claim 5, each lower buffer support, by Rukoto be composed of a coil spring and a shock absorber to cushion with a relatively small spring constant vibration of the cab body, the operation Since the vertical vibration of the chamber body can be buffered with a small spring constant,
By reducing the natural frequency of the entire cab can be effectively attenuate vertical vibration transmitted to the cab body, the effect of such a riding comfort of the vehicle can be greatly improved.

[Brief description of the drawings]

FIG. 1 is a partially broken external view showing a cab body, a turning frame, and the like according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken in the direction of arrows II-II in FIG.

FIG. 3 is a sectional view taken in the direction of arrows III-III in FIG.

FIG. 4 is a partially broken external view showing a cab main body, a turning frame, and the like according to a second embodiment of the present invention.

FIG. 5 is a sectional view taken in the direction of arrows VV in FIG. 4;

FIG. 6 is a sectional view taken along the line VI-VI in FIG.

FIG. 7 is a partially broken external view showing a cab body, a turning frame, and the like according to a third embodiment of the present invention.

FIG. 8 is a sectional view taken in the direction of arrows VIII-VIII in FIG.

9 is a sectional view taken in the direction of arrows IX-IX in FIG. 7;

FIG. 10 is an overall view showing a conventional hydraulic excavator.

FIG. 11 is a partially broken external view showing, on an enlarged scale, a turning frame, a cab body, and the like in FIG. 10;

FIG. 12 is an enlarged sectional view of a lower buffer support and the like shown in FIG. 11;

FIG. 13 is an explanatory diagram for analyzing vibration of a cab.

FIG. 14 is a characteristic diagram showing a relationship between a frequency ratio of forced vibration to a natural frequency of a cab and a vibration transmissibility.

[Explanation of symbols]

Reference Signs List 21 Revolving frame (body frame) 21A High rigidity part 21B Support part 21C Bracket part 22 Cab cab body 24 Floor plate 25 Lower buffer support 26 Shock absorber 27 Coil spring 28 Stopper 29, 30, 34, 35, 41, 42, 51, 51 54 Mounting bracket 31, 43, 46, 55, 59 Torsion bar 32, 44, 47, 56, 60 Link rod 33, 45, 48, 57, 61 Connecting rod 36 Link rod 63 Connecting link

──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Zenji Kaneko 650, Kandamachi, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. (72) Inventor Go Tsuyoshi 650, Kandamachi-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Tsuchiura Works Co., Ltd. (56) References JP-A-5-321295 (JP, A) JP-A-5-255950 (JP, A) JP-A-3-200485 (JP, A) JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) E02F 9/16 B62D 24/02

Claims (5)

(57) [Claims] 1. A box-shaped cab main body having a main body frame of a working machine, a floor panel provided on a lower surface of the main body frame, and a space between the floor panel and the main body frame of the cab main body. plurality is provided, in the lower buffer support and cab with working machine comprising a vibration from the body frame to buffer being transmitted to the cab body, between the floor plate and the body frame before Symbol cab body Is provided with a parallel link mechanism that allows the cab body to vibrate vertically on the body frame and restricts the vibration in the horizontal direction, and the parallel link mechanism includes at least one or more torsion bar. and, the torsion bar extending in the longitudinal direction of the cab body
And a pair of link rods separated in the left-right direction,
Link rods connected in the horizontal direction.
The front and rear ends of the torsion bar are
The floor panel of the room main body and the body frame are rotatably linked to each other.
A working machine with a driver's cab, wherein the working machine is configured to be connected. 2. The parallel link mechanism according to claim 1, wherein the torsion bar is separated from the torsion bar in a front-rear direction of the cab main body, and is rotated between a floor plate of the cab main body and a main body frame.
The working machine with a cab according to claim 1, comprising a link rod movably provided . 3. A main body frame of a working machine, and the main body frame.
Box-shaped box with a floor panel on the bottom side
Between the transfer body and the floor panel of the cab body and the body frame
And vibration from the main body frame is
A lower buffer support that buffers the transfer to the transfer room
In a working machine with a cab , the main body is provided between a floor plate of the cab main body and a main body frame.
Allow the cab body to vibrate vertically on the frame
And a parallel link mechanism that regulates horizontal vibration.
Provided, said parallel link mechanism includes a first spaced apart longitudinally between the floor plate and the body frame of the cab body, constituted by a second torsion bar, said first, second torsion bar, respectively extending in the longitudinal direction of the cab body, and a pair of link rods spaced in the lateral direction, consists of a connecting rod coupled between the respective link rods on the left and right direction, the first front and rear of the second torsion bars direction end side,
With a cab, wherein the cab body is configured to be rotatably connected to the floor plate and the body frame, respectively.
Work machine . 4. The first and second torsion bars include:
4. A transport link according to claim 3, further comprising a connecting link extending in the front-rear direction of the cab body and having both ends pin-coupled to the connecting rods so that the connecting rods rotate integrally.
Work machine with transfer room . 5. The lower cushioning support according to claim 1, 2, 3, or 4, wherein the lower cushioning support comprises a coil spring and a shock absorber that buffer the vibration of the cab body with a relatively small spring constant. Working machine with operator cab .