JP2000127730A - Suspension device for wheel running type construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the occurrence of a slip of a wheel during excavation movement work and improve ground leveling workability by preventing the occurrence of displacement in an attitude of an earthwork working machine. SOLUTION: This device performs ON-operation of a rear suspension lock switch 71 with a total suspension lock switch 70 brought into an OFF-state. The lock valve 56 of a tear suspension 50 positioned on the rear end side of a lower structure 10 is caused to effect ON-operation independently from the lock valve 46 of a front suspension 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension device applied to a construction machine, and more particularly, to a suspension base having a lock mechanism, in which front wheels and rear wheels are individually mounted on a traveling base. Suspended and run through these front and rear wheels,
The present invention relates to a suspension device for a wheel traveling type construction machine that performs a predetermined civil work via an earthworking machine provided on the traveling base.

[0002]

2. Description of the Related Art As a suspension apparatus applied to a wheel traveling type construction machine, for example, Japanese Patent Application Laid-Open No. 6-286446.
There is one shown in Japanese Patent Publication No. That is, in this suspension device, a lock mechanism is provided for each of the suspensions that suspend the front wheels and the rear wheels with respect to the chassis frame, and operation detection means for detecting whether the front working device is operating is provided. Further, suspension lock control means for operating the lock mechanism of each suspension based on the detection result of the operation detection means is provided.

When the operation detecting means detects that the front working device is operating, the suspension lock control means operates the locking mechanism of each suspension.

As a result, the strokes of the front wheels and the rear wheels with respect to the chassis frame are prevented,
Workability of various civil works by the above-described front working device is ensured.

On the other hand, when the operation detector detects that the operation of the front working device has stopped, the suspension lock controller releases the lock mechanism of each suspension.

As a result, the stroke of the front wheel and the rear wheel with respect to the chassis frame is allowed, the followability of these wheels with respect to the road surface is improved, and the vibration of the chassis frame is sufficiently attenuated. Therefore, the traveling performance of the wheel traveling type construction machine is improved, and the riding comfort can be improved.

[0007]

By the way, in the above-mentioned wheel traveling type construction machine, a front work machine equipped with a bucket is applied. Normally, earth and sand excavation work and excavation earth and sand loading work using the bucket of the front working machine are performed in a state where traveling of the wheel traveling type construction machine is stopped. Therefore, if both the locking mechanism of the front wheel suspension and the locking mechanism of the rear wheel suspension are operated as before, the earth excavation work and the excavation sedimentation by the front working machine can be performed in a stable state in which the vehicle body is prevented from shaking. Work can be performed.

However, when excavating and moving earth and sand while the wheel traveling type construction machine is running by applying the blade (discharge plate) of the earth working machine attached to the chassis frame, When both the lock mechanism of the front wheel suspension and the lock mechanism of the rear wheel suspension are operated as in the above, the ground contact property of each wheel is reduced on uneven terrain and slips easily, and the workability of terrain with blades is reduced. As the ride decreases, the ride quality also decreases.

[0009] On the other hand, when the locking mechanism of the suspension for all wheels is released and the excavating and moving work of the earth and sand is performed,
Although the grounding properties and ride comfort of the wheels are improved, the chassis frame moves up and down and left and right, and accordingly, the attitude of the blades is not constant, and there is a problem that horizontal leveling work cannot be performed.

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention is directed to a wheel traveling type construction machine in which an earthworking machine is provided on a traveling base and excavation and movement of earth and sand is performed while traveling. In addition, it is an object of the present invention to provide a suspension device for a wheel traveling type construction machine capable of preventing a displacement of an earthworking machine in posture and improving terrain workability.

A further object of the present invention is to provide a suspension device for a wheel traveling type construction machine, which is capable of switching between suspension control during traveling and suspension control for performing an excavation loading operation when traveling is stopped.

[0012]

Means for Solving the Problems and Functions and Effects
According to the invention described in the above, the front wheels and the rear wheels are individually suspended on the traveling base via suspensions each having a locking mechanism, and traveling through these front wheels and rear wheels, and the traveling base is In a suspension device for a wheel traveling type construction machine that performs a predetermined civil engineering work via an earthworking machine provided, a lock mechanism for one suspension located on the earthworking machine side of the traveling base is used to lock a suspension for the other suspension. Suspension lock control means for independently turning on the mechanism is provided.

According to the first aspect of the present invention, only the lock mechanism of the suspension located on the earthworking side can be turned on during the excavation moving operation. Therefore, the suspension whose locking mechanism is turned on can prevent the posture of the earth working machine from being displaced, and the stroller of the suspension whose locking mechanism is turned off secures the ability of the wheels to follow the road surface to reduce slip. be able to.

According to the first aspect of the present invention, the suspension lock control means for simultaneously turning on / off the lock mechanism of the one suspension and the lock mechanism of the other suspension as in the invention of the second aspect. (1) a second suspension locking means for turning on the locking mechanism of the one suspension while the first suspension locking means is turned off;
And a third suspension lock means for simultaneously turning on / off the lock mechanism of the one suspension and the lock mechanism of the other suspension, as in the invention according to claim 3, and Set the third suspension locking means to O
And a suspension unlocking means for turning off the lock mechanism of the other suspension in the N-operated state. Further, as in the invention according to claim 4, the lock mechanisms of the one suspension are individually turned on.
The fourth suspension locking means for N / OFF operation and the locking mechanism for the other suspension are individually O
A device including a fifth suspension lock unit that performs an N / OFF operation can be applied.

According to a fifth aspect of the present invention, in the first aspect, the second aspect, the third aspect or the fourth aspect, the earthwork machine is provided on a rear wheel side of the traveling base. A turning base is disposed on the traveling base so as to be able to turn, and the excavation loading machine is supported on the turning base so as to be able to move up and down.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings showing one embodiment. 4 to 6 show a wheel traveling type construction machine to which the first embodiment of the suspension device according to the present invention is applied. This wheel traveling type construction machine is mainly used when performing civil engineering work such as excavation, loading and earthwork at the construction work site,
An upper revolving unit (slewing base) 20 is provided above the lower traveling unit (running base) 10.

The upper revolving superstructure 20 is rotated by a revolving circle 30 interposed between the lower revolving superstructure 10 and the lower traveling superstructure 10 about a revolving axis α along a vertical axis.
It is arranged so as to be pivotable within a range of 0 °. In the wheel traveling type construction machine illustrated in the present embodiment, the above-described turning axis α
Is provided at a position offset to the vehicle rear side on the median surface of the lower traveling body 10. However, the turning axis α may be located anywhere between the lower traveling body 10 and the vehicle.

The upper revolving unit 20 is provided with a cabin 21 and a digging / loading work machine 22. The cabin 21 has a box shape on which a driver can sit, and is arranged at a position offset to the left with respect to the median surface of the lower traveling body 10. Excavator loading machine 22
Is suitable for performing a backhoe operation for excavating a place lower than the ground E on which the lower traveling body 10 is installed, and for loading the excavated earth and sand.
a and the bucket 22c is held via the arm 22b. The excavator / loader 22 is movably supported at a position offset to the right with respect to the median surface of the lower traveling unit 10.

On the other hand, the lower traveling body 10 of the wheel traveling type construction machine includes a chassis frame 11 as shown in FIG. The chassis frame 11 extends in the vehicle traveling direction (the direction of the arrow A in FIG. 3), and includes an earthworking machine 12 at a rear end thereof as shown in FIGS. The earthworking machine 12 is suitable for performing earthwork such as accumulation of excavated earth and sand and adjustment of the ground surface, and holds a blade 12b via a lift arm 12a so as to be liftable.

The chassis frame 11 is shown in FIG.
As shown in FIG. 3, front wheels FW are provided on both sides of the front end, and rear wheels RW are provided on both sides of the rear end. The front wheel FW and the rear wheel RW are called double tires, each of which includes a pair of tires. The front wheel FW is
Each of the right and left sides has an independent axle FA, and the chassis frame 11
Is suspended. On the other hand, the left and right rear wheels RW are connected to each other by a common axle RA, and this common axle RA is suspended from the chassis frame 11 via a rear suspension 50.

The front suspension 40 and the rear suspension 50 are each called a hydropneumatic suspension. That is, these suspensions include hydraulic cylinders 41 and 51, and communication conduits 42 and 52 that communicate the piston-side pressure chamber and the rod-side pressure chamber of the hydraulic cylinders 41 and 51 with each other.
Accumulators 43 and 53 filled with a gas such as nitrogen;
These accumulators 4 are provided through orifices 44 and 54.
3 and 53 and connecting conduits 45 and 55 for connecting between the communicating conduits 42 and 52, respectively.

In the suspensions 40 and 50, the pressure of the gas sealed in the accumulators 43 and 53 determines the spring constant of each suspension 40 and 50. Specifically, the spring constant increases as the gas filling pressure decreases.

The orifices 44, 54 interposed between the communication pipes 42, 52 act to generate a damping force on the suspensions 40, 50, respectively.

Further, the pressure of the oil sealed in the hydraulic cylinders 41, 51 determines the attitude of the wheel traveling type construction machine.
As described above, in the wheel traveling type construction machine of the present embodiment, the excavator / loader 22 is supported on the upper revolving unit 20 at a position offset to the right with respect to the median plane. In the normal state shown in FIG. 5, the center of gravity is shifted to the right side of the median plane. Therefore, in the right suspensions 40 and 50, the oil filling pressure of the hydraulic cylinders 41 and 51 is set higher than that in the left suspensions 40 and 50, so that the wheel traveling type construction machine is kept horizontal in the above-described normal state. ing.

As is apparent from FIG. 1, the suspensions 40 and 50 have respective communication conduits 42 and 5 respectively.
2 individual suspension lock valve (lock mechanism)
46 and 56 are provided. The suspension lock valves 46 and 56 are for switching the corresponding suspensions 40 and 50 between a locked state and an unlocked state by interrupting the communication conduits 42 and 52 described above. That is, the suspension lock valves 46, 56
Stops the flow of oil between the piston side pressure chamber and the rod side pressure chamber in the corresponding hydraulic cylinders 41, 51 when the communication pipelines 42, 52 are shut off (ON). As a result, the stroke of the hydraulic cylinders 41 and 51 is prevented, and the suspensions 40 and 50 are locked. On the other hand, when the communication pipes 42 and 52 are connected to each other (OFF), the corresponding hydraulic cylinder 4
The flow of oil between the piston-side pressure chambers and the rod-side pressure chambers is allowed. As a result, the hydraulic cylinder 4
1 and 51 can make a stroke, and the suspensions 40 and 50 are unlocked. Reference numeral 60 in the figure denotes a conduit for connecting the rod-side pressure chambers of the hydraulic cylinders 41 and 51 to each other in the front suspension 40, and a suspension communication control valve 61.
Is provided.

These suspension lock valves 46,
The operation of each of 56 is controlled by a full suspension lock switch (first suspension lock means) 70 and a rear suspension lock switch (second suspension lock means) 71.

All suspension lock switches 70
The front suspension lock valve 46 and the rear suspension lock valve 56 are simultaneously turned on / off. The rear suspension lock switch 71 turns on / off the rear suspension lock valve 56 separately from the operation of all the suspension lock switches.
The FF operation is performed. FIG. 2 shows the operation states of the front suspension lock valve 46 and the rear suspension lock valve 56 when the all suspension lock switch 70 and the rear suspension lock switch 71 are combined. Note that reference numeral 80 in FIG.
Is an electric swivel joint.

In the above-described wheel traveling type construction machine,
When the earth working machine 12 is applied, it is assumed that various civil works are performed on the rear end side of the lower traveling body 10.
Power from an engine (not shown) is supplied to the front wheel FW.
The drive system is configured to be transmitted to each of the rear wheels RW.

Hereinafter, lock control of the suspension device in the wheel traveling type construction machine will be described.

First, when the wheel traveling type construction machine is run, both the front suspension lock valve 46 and the rear suspension lock valve 56 are operated by turning off both the suspension lock switch 70 and the rear suspension lock switch 71.
Are turned off.

In this state, since both the front suspension 40 and the rear suspension 50 are in the unlocked state, the stroke of the front wheel FW and the rear wheel RW with respect to the chassis frame 11 is allowed. As a result, according to the wheel traveling type construction machine, the followability of the wheels FW and RW to the ground E is improved, the traveling performance is improved when traveling on a public road, and the vibration of the chassis frame 11 is sufficiently reduced. As a result, the ride comfort is improved.

On the other hand, when the blade 12b of the earth working machine 12 is applied and the excavation and moving operation of the earth and sand is performed while the wheel traveling type construction machine is running, the front suspension lock switch 70 is turned off. At the same time, by turning on the rear suspension lock switch 71, only the rear suspension lock valve 56 is turned on.

Here, as described above, in the wheel traveling type construction machine of the present embodiment, the center of gravity of the upper revolving unit 20 is shifted to the right side due to the weight of the excavator / loader 22.
When the upper revolving unit 20 is turned in a state where both the front suspension 40 and the rear suspension 50 are in a stroke, the weight of the excavating / loading work machine 22 supported by the upper revolving unit 20 moves, and the upper revolving unit 2 is moved.
The chassis frame 11 on which the 0 is mounted tilts.
At this time, as the chassis frame 11 is tilted, the blade 12b held by the chassis frame 11 is also tilted integrally. The inclination of the blade 12b depends on the turning angle of the upper turning body 20 with respect to the chassis frame 11. Therefore, the upper revolving superstructure 2
When the rear suspension lock switch 71 is turned on while the blade 12b is at a desired tilt angle, the blade 12b can be fixed to the ground E at that tilt angle.

That is, the blade 12b is
Is set to a horizontal state, the rear suspension lock switch 71 is turned ON in a state before the upper swing body 20 turns, and then the upper swing body 20 is
It only has to be turned 0 °.

In this state, the front suspension 40 is unlocked and the rear suspension 50 is locked, that is, only the rear suspension 50 provided at the position on the lower traveling body 10 on the working side is locked. In this state, the stroke of the front wheel FW with respect to the chassis frame 11 is allowed, while the stroke of the rear wheel RW is prevented.

Therefore, the front wheel FW reliably follows the ground E while maintaining the attitude of the blade 12b arranged on the rear wheel RW side in a horizontal state.
Sufficient running performance can be secured in earthworks.

At this time, the vibration of the wheel traveling type construction machine can be sufficiently absorbed by the front suspension 40, and even when the earth work is performed by the earth work machine 12, the operation work sitting on the cabin 21 is performed. The burden on the person can be reduced.

As described above, according to the wheel traveling type construction machine, when the blade 12b of the earth working machine 12 is applied to perform the excavation moving operation of the earth and sand with the wheel traveling type construction machine running. Only the lock valve 56 of the rear suspension 50 located on the earthworking machine 12 side is turned on. Therefore, the earth working machine 12
Is operating, the front suspension 40 makes a stroke while maintaining the attitude of the blade 12b, and the front suspension 40 can ensure the followability to the ground E and sufficiently reduce the vibration. It becomes possible to absorb.

On the other hand, when the earth excavation work and the earth excavation work are performed by the excavation loading machine 22 provided on the upper swing body 20, the traveling of the wheel traveling construction machine is stopped as described above. In order to perform the operation in the state, all of the front suspension lock valve 46 and the rear suspension lock valve 56 may be turned on by turning on all the suspension lock switches 70.

In the first embodiment described above, the suspension lock valves 46 and 56 are turned on / off by the all suspension lock switch 70 and the rear suspension lock switch 71. It is not limited to.

For example, as in the second embodiment shown in FIG. 7, a full suspension lock switch (third suspension lock means) 100 and a front suspension lock switch (suspension unlock means) 101
And the suspension lock valves 46 and 56 are
An N / OFF operation may be performed, or a front suspension lock switch (fifth suspension lock means) 110 as in the third embodiment shown in FIG.
In addition, the suspension lock valves 46 and 56 can be turned on / off by the rear suspension lock switch (fourth suspension lock means) 111 and the rear suspension lock switch 111. That is, the front suspension lock valve 46 according to the combination of the second embodiment.
As shown in FIG. 8 showing the operation state of the rear suspension lock valve 56 and the operation state of the front suspension lock valve 46 and the rear suspension lock valve 56 according to the combination of the third embodiment, FIG. Only the rear suspension 50 provided on the body 10 at a position on the earthworking machine 12 side can be locked.

Therefore, even when the second embodiment and the third embodiment are applied, similarly to the first embodiment, the attitude of the blade 12b disposed on the rear wheel RW side is not changed. The front wheels FW reliably follow the road surface, sufficient running performance can be ensured in earthwork, and the vibration of the wheel traveling type construction machine is reduced by the front suspension 4.
0 makes it possible to absorb sufficiently, and it is possible to reduce the burden on the driver sitting on the cabin 21.

The first to third embodiments described above are applied to the undercarriage 10 with the earth working machine 12.
Is not necessarily required to be provided with the upper swing body 20. Also, a wheel traveling type construction machine that works on the rear end side of the lower traveling body 10 is illustrated, but one that works on the front end side of the lower traveling body 10 or the lower traveling body 10
It is also possible to apply the present invention to a device that works at both front and rear ends. Further, the suspension lock switch 70,
ON / OFF of 71,100,101,110,111
The operation may be either manual switching or automatic switching. However, the suspension lock switch 70,
ON / OFF of 71,100,101,110,111
When the operation is automatically switched, a suspension lock switch on the earthworking machine side is turned on based on a control signal indicating a state of operating the earthworking machine such as a blade operation lever. Is preferred. A suspension called a hydropneumatic suspension is applied as the suspensions 40 and 50, and a communication mechanism 42 is used as a lock mechanism to communicate the piston-side pressure chambers and the rod-side pressure chambers of the hydraulic cylinders 41 and 51 with each other. Although the example in which the lock valves 46 and 56 are interposed in 52 is illustrated, other types of suspensions and lock mechanisms may be applied. In this case, it is not necessary for the front wheels FW to have independent axles FA, nor for the rear wheels RW to be connected to each other by a common axle RA.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a first embodiment of a suspension device according to the present invention.

FIG. 2 is a table showing an operation state of a suspension lock valve in the suspension device shown in FIG.

3 is a perspective view conceptually showing a traveling base of a wheel traveling type construction machine to which the suspension device shown in FIG. 1 is applied.

FIG. 4 is a left side view showing a wheel traveling type construction machine to which the suspension device shown in FIG. 1 is applied.

FIG. 5 is a view taken in the direction of arrows in FIG.

FIG. 6 is a view taken along arrow VI in FIG. 4;

FIG. 7 is a circuit diagram showing a second embodiment of the suspension device according to the present invention.

8 is a table showing an operation state of a suspension lock valve in the suspension device shown in FIG.

FIG. 9 is a circuit diagram showing a third embodiment of the suspension device according to the present invention.

10 is a table showing an operation state of a suspension lock valve in the suspension device shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Lower traveling body, 12 ... Earthworking machine, 20 ... Upper revolving body, 22 ... Excavation loading machine, 40 ... Front suspension, 46, 56 ... Lock valve, 50 ... Rear suspension, 70 ... Full suspension lock switch, 71
... rear suspension lock switch, 100 ... all suspension lock switch, 101 ... front suspension lock switch, 110 ... front suspension lock switch, 111 ... rear suspension lock switch, FW ... front wheel, RW ... rear wheel.

Claims (5)

[Claims] 1. A front wheel and a rear wheel are individually suspended on a traveling base via suspensions each having a lock mechanism, and the vehicle travels via the front wheels and the rear wheels, and is provided on the traveling base. A suspension device for a wheel traveling type construction machine that performs predetermined civil engineering work via an earthworking machine, wherein a lock mechanism for one suspension located on the earthworking machine side of the traveling base is a lock mechanism for the other suspension. A suspension device for a wheel traveling type construction machine, wherein a suspension lock control means for independently turning on the vehicle is provided. 2. The suspension lock control means includes: first suspension lock means for simultaneously turning on / off the lock mechanism of the one suspension and lock mechanism of the other suspension; and OFF operation of the first suspension lock means. The suspension device for a wheel traveling type construction machine according to claim 1, further comprising: a second suspension lock unit that turns on a lock mechanism of the one suspension in a state where the suspension is performed. 3. The suspension lock control means includes: a third suspension lock means for simultaneously turning on / off the lock mechanism of the one suspension and the lock mechanism of the other suspension; and an ON operation of the third suspension lock means. The suspension device for a wheel traveling type construction machine according to claim 1, further comprising: suspension unlocking means for turning off a lock mechanism of the other suspension in a state where the suspension is operated. 4. The suspension lock control means individually turns on / off a lock mechanism of the one suspension.
The fourth suspension locking means for performing the OFF operation and the locking mechanism of the other suspension are individually turned ON / OFF.
The suspension device for a wheel traveling type construction machine according to claim 1, further comprising: a fifth suspension lock unit that performs an OFF operation. 5. An earthworking machine is provided on a rear wheel side of the traveling base, and a turning base is disposed on the traveling base so as to be pivotable, and an excavation loading operation is performed on the turning base. The suspension device for a wheel traveling type construction machine according to claim 1, wherein the machine is supported so as to be able to move up and down in a vertical direction.