JPH06136787A - Working machine with operation room - Google Patents

Abstract

PURPOSE:To prevent the transmission of a vibration or a noise from the outer side to the inside of an operation room, so as to reduce the fatigue of an operator. CONSTITUTION:A floor plate 31 is fixed directly on a rotary frame 4 through bolts 34, and vibration isolators 37 are provided between brackets 32 at the floor plate side of the floor plate 31, and brackets 36 at the main body side of an operation room main body 35, to hold the brackets 32 at the floor plate side with vibration-proof rubbers 39 from the upper side and the lower side. By fixing the floor plate 31 directly to the rotary frame 4 with a high rigidity, the intrinsic vibration frequency of the floor plate 31 is set higher than the frequency to give an unpleasant feeling to an operator to prevent to give the vibration of a low frequency, so as to reduce his fatigue.

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 such as a hydraulic excavator.

[0002]

2. Description of the Related Art FIGS. 4 to 7 show a hydraulic excavator 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, and 3 is an upper revolving structure which is rotatably mounted on the lower traveling body 1 through the turning device 2 and constitutes a working machine body. The upper revolving structure 3 is composed of a revolving frame 4 as a frame having a frame structure, a machine room 5, a driver's cab 6 and a counterweight 7 provided on the revolving frame 4, and a front portion of the revolving frame 4 is provided. Is integrally provided with a mounting bracket 4A located on the right side of the operator's cab 6 for a working device 8 described later. The turning frame 4 is composed of a center frame, a side frame, a connecting frame and the like.

Reference numeral 8 denotes a working device provided in the front part of the upper swing body 3, and the working device 8 is a boom 9 provided on a mounting bracket 4A of the swing frame 4 so as to be able to move up and down, and a boom 9 of the boom 9. Arm 10 provided on the tip side so as to be able to move downward
And a bucket 11 rotatably provided on the tip side of the arm 10, and these boom 9, arm 10 and bucket 11 are operated by a boom cylinder 12, an arm cylinder 13 and a bucket cylinder 14.

Reference numeral 15 denotes a floor plate which constitutes the bottom side of the operator's cab 6, and the floor plate 15 is formed of a metal plate in a substantially rectangular shape. As shown in FIG. It is attached via a vibration isolator 18.

Reference numeral 16 denotes a driver's cab main body portion which is provided on the floor plate 15 and constitutes an upper side of the operator's cab 6. The operator's cab main body portion 16 has a front surface portion 16A and a rear surface portion 16 as shown in FIG.
B, the left and right side surface portions 16C (only one is shown) and the ceiling portion 16D are formed as a box-shaped cab box. In addition, the driver's cab main body 16 has a front portion 16A,
The floor board 15 is provided on the lower end sides of the rear surface portion 16B and the side surface portions 16C.
A floor plate bracket 16E for fixing the vehicle is provided, and a door 17 for allowing an operator to get in and out of the driver's cab main body 16 is provided on the right side surface portion 16C so as to be opened and closed.

Reference numerals 18, 18, ... Depict vibration damping members provided between the floor plate 15 of the cab 6 and the slewing frame 4 in order to buffer the transmission of vibrations from the slewing frame 4 to the cab 6. The vibration isolator 18 is provided at four corners of the floor plate 15 in front, rear, left, and right positions, for example, four in number. As shown in FIG. 6, each vibration isolator 18 has a pair of stoppers 19, 1
9 and the respective stoppers 19, and the swivel frame 4
A pair of anti-vibration rubbers 20, 20 that sandwich the upper surface portion 4B of the
A cylindrical spacer 21 penetrating the central portion of each vibration isolating rubber 20 and inserted into a mounting hole 4C formed in the upper surface portion 4B of the swivel frame 4, and an outer side of the spacer 21 and the swivel frame. An annular vibration-proof rubber 22 inserted between the mounting holes 4C of 4 and a bolt 24 inserted into the spacer 21 from the turning frame 4 side and having a nut 23 tightened on the floor plate bracket 16E; It consists of

Here, in each of the vibration isolator 18, by strongly screwing the nut 23 to the bolt 24, the vibration isolator 20 is compressed and deformed between the stoppers 19, and the initial load is applied to the antivibration rubber 20. The upper surface portion 4B of the revolving frame 4 with
Is strongly pinched. The vibration isolator 18 supports the entire driver's cab 6 on the swivel frame 4 via the anti-vibration rubbers 20 to prevent the operator's cab 6 from vibrating upward and downward. .

In the hydraulic excavator constructed as above,
By supplying / discharging pressure oil to / from the traveling hydraulic motor (not shown) of the lower traveling structure 1 and the cylinders 12, 13, 14 of the working device 8 and the like, these are actuated so that the vehicle is caused to travel, earth and sand, etc. I try to do excavation work.

Then, vibrations due to vibrations during traveling and vibrations due to excavation reaction during work are transmitted to the cab 6 via the swivel frame 4 by the vibration-proof rubbers 20 and 20 of the respective vibration-proof bodies 18 to buffer the vibrations. The ride comfort of the room 6 is not deteriorated.

[0011]

By the way, in the above-mentioned prior art, the spring constant of each vibration isolator 18 arranged between the upper surface 4A of the swivel frame 4 and the floor plate 15 is set as small as possible. Each vibration isolator 18 has a large buffering effect to prevent the vibration from the revolving frame 4 from being transmitted to the inside of the cab 6.

However, each vibration isolator 18 that supports the cab 6
When the spring constant k of is reduced, the cab 6 (floor board 1
Since the natural frequency f (including 5) becomes low as shown by the characteristic line 25 shown in FIG. 7, the human body enters a low frequency region (below the boundary line 26) where the human body feels particularly uncomfortable, and the inside of the cab 6 There is a problem in that the operator is easily exposed to vibrations of low frequency and becomes tired, which deteriorates habitability and operability.

Further, even if the spring constant k of each vibration isolator 18 is made as small as possible and the natural frequency of the driver's cab 6 is lowered, the effect of blocking noise propagating from the outside into the operator's cab 6 is low, There is a problem that the noise makes the operator uncomfortable.

The present invention has been made in view of the above-mentioned problems of the prior art. The present invention can prevent an operator in a driver's cab from being exposed to vibration of a low frequency, and at the same time, noise can be propagated from the outside into the driver's cab. It is an object of the present invention to provide a working machine with a driver's cab, which can prevent the above-mentioned problems and reduce operator fatigue.

[0015]

In order to solve the above-mentioned problems, the features of the structure adopted by the present invention are that the cab is provided with a floor plate directly fixed to the frame, and the front panel is provided on the floor plate. Section, the rear surface section, the left and right side surface sections and the ceiling section are provided in a box shape between a driver's cab main body, the lower end side of the driver's cab main body and the floor board, and the vibration of the floor board is provided. It is composed of a vibration isolator that suppresses transmission to the cab body.

In this case, it is preferable to dispose a seal member made of an elastic material between the floor plate and the operator's cab main body so as to fill the gap between them.

[0017]

With the above construction, since the floor plate is directly fixed to the frame, the natural frequency of the floor plate can be set to a frequency range higher than the frequency at which the human body feels uncomfortable. By disposing the driver's cab body on the floor plate via the vibration proof body, the vibration of the cab body can be suppressed to a low level, and the spring constant of the vibration proof body is set to the optimum value for noise reduction. Can be set to.

Further, if a seal member made of an elastic material is disposed between the floor plate and the driver's cab body, when the floor plate vibrates, the seal member elastically deforms and absorbs the vibration, and noise in the driver's cab is generated. Can be prevented from propagating.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. In addition, in the embodiment, the same components as those of the above-described conventional technique are designated by the same reference numerals, and the description thereof will be omitted.

In the figure, 30 is a driver's cab according to this embodiment, 31
Indicates a floor plate of the cab 30, the floor plate 31 is formed in a substantially rectangular shape, a floor plate side bracket 32 having a U-shaped cross section is attached to the upper surface side of the floor plate 31, and each floor plate side bracket 32 is The lower end side is welded to the upper surfaces of the four corners of the floor plate 31 and fixed to the floor plate 31. As shown in FIG. 2, each floor board side bracket 32 has a leg portion 32A and a lid portion 32B.
And a mounting hole 32C is formed in the center of the lid portion 32B. Further, an annular boss portion 33 is welded and fixed to the lower surface side of the floor plate 31 at a position facing each floor plate side bracket 32, and a bolt 34 is fastened to each boss portion 33 from the turning frame 4 side. Thus, the floor plate 31 is directly fixed on the upper surface portion 4B of the revolving frame 4.

Reference numeral 35 denotes a driver's cab main body which constitutes the driver's cab 30 together with the floor plate 31. The driver's cab main body 35 is substantially the same as the driver's cab main body 16 described in the above-mentioned prior art, and the front face 3
5A, a rear surface portion 35B, left and right side surface portions 35C (only one is shown) and a ceiling portion 35D, the inner lower end portion of the driver's cab body 35 is attached to the floor plate 31. A main body side bracket 36 is provided so as to surround the periphery.

Here, the main body side bracket 36 is a frame plate portion 36 of a substantially quadrangular shape arranged at the lower end side of the cab main body portion 35.
A and bulging portions 36B, 36B, ... Which are located at the four corners of the frame plate portion 36A and bulge upward and are formed in a substantially fan shape, and are formed at the center of the upper surface side of each bulging portion 36B. Has a mounting hole 36C. Then, as shown in FIG. 2, inside each of the bulging portions 36B, each of the vibration isolator 37 described later is arranged between the floor plate 31 and each of the floor plate side brackets 32.

Denoted by 37, 37, ... are four vibration isolators located at the corners between the bulging portions 36B of the main body side bracket 36 and the floor plate side bracket 32, respectively. Body 3
Numeral 7 designates stoppers 38, 38, anti-vibration rubbers 39, 39, spacers 4 in the same manner as the anti-vibration body 18 described in the above-mentioned prior art.
0, ring-shaped anti-vibration rubber 41, bolts 42 and nuts 43
It consists of

In the vibration isolator 37, the spacer 40 is inserted through the vibration isolating rubber 41 into the mounting hole 32C of the floor plate side bracket 32, and the vibration isolating rubber 39 arranged on the outer peripheral side of the spacer 40. The floor plate side bracket 32 is clamped from above and below, and each stopper 38 is provided above and below each anti-vibration rubber 39.
And is mounted between the floor plate side bracket 32 and the main body side bracket 36 via a bolt 42 and a nut 43. In this case, the vibration-proof body 37 is constructed such that the nut 43 is screwed in the floor plate side bracket 32 to the tip end side of the bolt 42 inserted into the spacer 40 from each bulging portion 36B of the body side bracket 36 through the mounting hole 36C. By wearing
An initial load is applied to each anti-vibration rubber 39.

Reference numeral 44 denotes a seal member, and the seal member 4
4 is made of an elastic material and is formed into a substantially quadrangular frame shape as shown in FIG. 3, and when the driver's cab main body part 35 is attached to the floor plate 31, it is between the floor plate 31 and the frame plate part 36A of the main body side bracket 36. It is installed in. The seal member 44 fills a gap between the floor plate 31 and the lower end side of the driver's cab main body 35, and the driver's cab main body 35 mounts each anti-vibration rubber 39 on the floor plate 31.
When the vehicle is relatively displaced through such factors as described above, it is elastically deformed in response to the relative displacement and suppresses noise from entering the cab 30.

Further, reference numeral 45 denotes a seat provided in the driver's cab main body portion 35, and the seat 45 is the shock absorber 4
It is mounted on the floor plate 31 via a seat suspension 48 composed of 6 and a spring 47. And the seat 4
The vibration 5 from the floor plate 31 is buffered by the seat suspension 48 to improve the riding comfort of the operator seated in the seat 45.

The present invention has the configuration described above, and its basic operation is not significantly different from that of the prior art.

However, in this embodiment, the floor plate 31 of the operator's cab 30 is fixed directly on the revolving frame 4 via the bolts 34, and between the floor plate 31 and the lower end side of the operator's cab main body 35, Each vibration isolator 37 is disposed between the main body side brackets 36 so that the lid portion 32B of each floor plate side bracket 32 is sandwiched by each vibration isolating rubber 39 from above and below, and the bolts are provided via each vibration isolator 37. 42, the floor plate side bracket 32 and the main body side bracket 36 are connected by the nut 43, and the seal member 44 made of an elastic material is arranged between the floor plate 31 and the frame plate portion 36A of the main body side bracket 36. ,
The following operational effects are achieved.

That is, according to this embodiment, since the floor plate 31 is directly fixed to the highly rigid revolving frame 4, the floor plate 3 is fixed.
The natural frequency f of 1 can be set to a relatively high frequency as a characteristic line 49 shown in FIG. 7, and the natural frequency f of the floor plate 31 is a frequency at which a human body feels uncomfortable (the boundary line shown in FIG. 7). Two
It can be set to a higher frequency range than 6).

Further, the vibration transmitted from the revolving frame 4 to the seat 45 via the floor plate 31 is transmitted to the seat suspension 48.
Since it can be damped by the buffering effect of, even if a large vibration is transmitted to the floor plate 31 of the cab 30 from the outside during work,
The vibration transmitted to the operator on the seat 45 in the cab 30 can be effectively reduced by the seat suspension 48. As a result, it is possible to prevent the operator in the cab 30 from being exposed to low-frequency vibration as described in the related art, and improve the habitability and operability in the cab 30,
It is possible to reduce operator fatigue.

Further, since each vibration isolator 37 is arranged between the floor plate 31 of the cab 30 and the lower end side of the cab body 35,
The vibration of the floor plate 31 can be buffered from being transmitted to the driver's cab main body portion 35, and the noise transmitted to the driver's cab 30 can be suppressed to a low level by appropriately setting the spring constant k of each vibration isolator 37.

Further, vibrations are generated from the swivel frame 4 to the floor plate 3.
1 is transmitted to the floor plate 31 and the body side bracket 36
This vibration can be absorbed when the seal member 44 provided between and is elastically deformed, and the vibration of the entire cab 30 can be reduced.
It is possible to prevent the sound from entering the driver's cab 30 from between and to suppress the sound in the driver's cab to a low level.

Therefore, according to the present invention, it is possible to effectively reduce the vibration and noise propagating in the cab 30, and to significantly reduce the discomfort and fatigue felt by the operator.

Although the hydraulic excavator has been described as an example of the working machine in the above embodiment, the present invention is not limited to this, and may be used for working machines such as hydraulic cranes and wheel loaders.

[0035]

As described in detail above, according to the present invention, the operator's cab is provided with the floor plate directly fixed to the frame, and the front panel, the rear panel, the left and right side panels provided on the floor panel. And a vibration isolator that is provided between the operator's cab main body formed in a box shape from the ceiling and the floor plate and the lower end side of the operator's cab main body, and suppresses the vibration of the floor plate from being transmitted to the operator's cab main body. Since it is composed of the body and body, it is possible to set the natural frequency of the floorboard to a higher level to prevent it from being exposed to low-frequency vibrations that the operator feels uncomfortable, improving operability and habitability and reducing operator fatigue. Can be made.

Further, according to the present invention, since the spring constant of the vibration isolator supporting the driver's cab main body can be set independently of the natural frequency of the floor plate, the spring constant of the vibration isolator transmits noise. It can be set to the optimum value for prevention, and the quietness inside the cab can be improved.

Further, by disposing a seal member made of an elastic material between the floor plate and the driver's cab body, the vibration transmitted from the revolving frame to the floor plate can be absorbed by the elastic deformation of the seal member, and the driver's cab can be absorbed. Various effects such as suppressing vibration and noise propagating up to and more effectively reducing operator discomfort and fatigue can be achieved.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing a working machine with a cab according to an embodiment of the present invention.

2 is an enlarged vertical sectional view showing a vibration isolator and the like in FIG.

FIG. 3 shows the shape of a seal member and the like in FIG.
It is a III direction sectional drawing.

FIG. 4 is an overall view showing a hydraulic excavator according to a conventional technique.

5 is a partially cutaway front view showing an enlarged cab in FIG. 4. FIG.

FIG. 6 is an enlarged vertical sectional view showing a vibration isolator and the like in FIG.

FIG. 7 is a characteristic diagram showing the relationship between the spring constant of the vibration isolator and the natural frequency of the cab.

[Explanation of symbols]

 4 Swiveling frame (frame) 30 Driver's cab 31 Floor plate 35 Driver's cab main body 35A Front face 35B Rear face 35C Side 35D Ceiling 37 Vibration proof 44 Seal member

Claims (2)

[Claims] 1. A work machine with a cab, comprising a frame of the work machine and a cab provided on the frame,
The cab includes a floor plate directly fixed to the frame, and a cab main body portion provided on the floor plate and formed in a box shape from a front surface portion, a rear surface portion, left and right side surface portions, and a ceiling portion. A work machine with a driver's cab, which is provided between a lower end side of the driver's cab body and the floor plate, and a vibration isolator for suppressing vibration of the floor plate from being transmitted to the driver's cab body. . 2. The driver's cab according to claim 1, wherein a seal member made of an elastic material is provided between the floor plate and the driver's cab main body so as to fill a gap therebetween. With working machine.