KR20090110837A - Vibration suppression device for hydraulic working machine and hydraulic working machine - Google Patents

Abstract

A vibration suppression device for a hydraulic working machine, the vibration suppression device being connected via pipe paths (L3, L4) to a hydraulic actuator (2), which is driven by pressurized oil from a hydraulic pressure source (1), and suppressing vibration of the hydraulic actuator (2). The vibration suppression device has an accumulator (13) having a gas chamber (R2) expanding and contracting by hydraulic pressure of the pressurized oil in the pipe path (L4) and also has a shutoff valve (12) closing when the hydraulic pressure is lower than or equal to a preset pressure (Pb) of gas in the gas chamber (R2) to shutoff pressurized oil flowing out of the accumulator (13).

Description

VIBRATION SUPPRESSION DEVICE FOR HYDRAULIC WORKING MACHINE AND HYDRAULIC WORKING MACHINE}

The present invention relates to a vibration suppressing apparatus and a hydraulic working machine of a hydraulic working machine for suppressing vibrations such as working booleans.

As a vibration suppressing device of this kind, a accumulator is conventionally connected to a bottom chamber of a boom cylinder via a variable throttle, and a pressure fluctuation of the pour cylinder is reduced by accumulating the accumulator and attenuating the variable throttle. A device for suppressing vibration of a device is known (see Patent Document 1, for example).

[Patent Document 1]

Japanese Patent Laid-Open No. 6-330535

In such a vibration suppressing device, if the pressure in the bottom chamber of the boom cylinder fluctuates, the movable part (e.g. bladder) in the accumulator collides with the fixed part (e.g. poppet), and the accumulator may be damaged.

The present invention is a vibration suppression apparatus of a hydraulic working machine connected to a hydraulic actuator driven by pressure oil from a hydraulic source via a pipeline, and suppressing vibration of the hydraulic actuator, the expansion and contraction of the hydraulic pressure of the pressure oil in the pipeline. An accumulator having a gas chamber and a shutoff valve for closing the hydraulic oil flowing from the accumulator when the hydraulic pressure acting on the accumulator is below the set pressure of the gas enclosed in the gas chamber are provided.

The vibration suppression apparatus of the hydraulic working machine according to the present invention is provided in a boom cylinder for driving a work boom rotatably installed in the upper swing body by pressure oil from a hydraulic source, and a pressure oil inflow and out port of the bottom chamber of the boom cylinder. A rupture valve with a built-in pilot operated check valve for blocking the outflow of the pressurized oil from the bottom chamber of the boom cylinder when the pilot operating pressure applied to the cylinder is less than or equal to a predetermined value, the pilot operated check valve and the boolean cylinder An accumulator having a gas chamber which is connected to a branch line branched from a connecting line connecting the pressure oil inflow and outflow port of the bottom chamber of the bottom chamber, and expands and contracts by the hydraulic pressure of the pressurized oil in the branch line, and a hydraulic force acting on the accumulator When it is below the set pressure of the gas enclosed in the said gas chamber, it closes and flows from the accumulator. It is provided with a blocking valve to block pressure oil.

Accumulators and shut-off valves can be installed on each boolean.

An accumulator and a shutoff valve can also be installed in the upper swing body, respectively.

At the same time, a pair of boolean cylinders are provided, and a rupture valve is installed in each boolean cylinder, and a pair of connection pipes connecting the pilot operated check valve of each rupture valve and the pressure oil inflow and outflow port of the bottom chamber of each boolean cylinder are installed. The branch circuits branched from each other are connected to each other via a throttle to form a tuning conduit, and a pair of bypass conduits are formed by bypassing the throttle to connect each connection conduit and the accumulator, respectively. May be connected to the tuning pipe line, and the isolation valves may be provided in a pair of bypass pipes, respectively.

The shut-off valve may be configured as an on-off valve, so that the on-off valve is opened when the hydraulic pressure is greater than the set pressure, and closed when the hydraulic pressure is below the set pressure.

The hydraulic work machine according to the present invention includes a lower traveling body, an upper swinging structure provided on the lower traveling body via a swing device, a working front including at least a pour, the vibration suppressing device, and a hydraulic cylinder from the hydraulic source to the pour cylinder. And a control valve for controlling the flow of the pressurized oil, and an operation unit for outputting a pilot operation pressure to operate the control valve.

According to the present invention, when the hydraulic force acting on the accumulator is lower than the set pressure of the gas, the accumulator is shut off from the hydraulic actuator, so that the accumulator can be prevented even when the pressure in the bottom chamber of the boom cylinder suddenly changes. have.

1 is a hydraulic circuit diagram showing a configuration of a vibration suppressing apparatus according to a first embodiment of the present invention;

FIG. 2 is a diagram showing the configuration of the accumulator of FIG. 1;

3 is an external side view of a hydraulic excavator according to a second embodiment of the present invention;

4 is a hydraulic circuit diagram showing a configuration of a vibration suppressing apparatus according to a second embodiment;

5 is a hydraulic circuit diagram showing a configuration of a vibration suppressing device according to a third embodiment;

6 is an enlarged view of a main part of FIG. 5;

7 is an external side view of a hydraulic excavator according to a third embodiment;

8 is a hydraulic circuit diagram showing a configuration of a vibration suppressing apparatus according to a fourth embodiment;

9 is a view showing a modification of FIG. 8;

10 is a view showing a modification of the pilot check valve incorporated in the break valve.

First Embodiment

EMBODIMENT OF THE INVENTION Hereinafter, with reference to FIG. 1, FIG. 2, 1st Embodiment of the vibration suppression apparatus of the hydraulic work machine which concerns on this invention is described.

1 is a hydraulic circuit diagram showing the configuration of a vibration suppressing apparatus according to a first embodiment, and shows an example applied to a boom cylinder of a hydraulic excavator. The circuit of FIG. 1 is a pour cylinder 2 driven by the hydraulic pump 1, the discharge oil from the hydraulic pump 1 supplied through the pipelines L1, L2, and the pour cylinder from the hydraulic pump 1 The direction control valve 3 which controls the flow of the hydraulic oil to (2), and the vibration suppression apparatus 10 which suppresses the vibration of the swelling cylinder 2 are provided.

The direction control valve 3 is converted by the pilot pressure generated by the operation of the operation lever 4. The maximum discharge pressure of the hydraulic pump 1 is limited by the relief valve 5. The conduits L1 and L2 are each formed by a flexible hydraulic hose, the conduits L1 to the rod chamber 2a of the cylinder 2, and the conduits L2 to the bottom chamber 2b, respectively. Connected.

The vibration suppressor 10 includes a variable throttle valve 11 provided in a conduit L3 branched from a conduit L2 and a counter balance connected in series to the variable throttle valve 11 via conduits L3 and L4. The valve 12 and the accumulator 13 and the check valve 14 connected in parallel with the counter balance valve 12 are provided.

The variable throttle valve 11 is for obtaining the damping action of the pulsation of oil, and the throttle area can be appropriately set. Instead of the variable throttle valve 11, a fixed throttle valve may be used, or a pipe resistance may be used. The counter balance valve 12 opens when the pressure P4 in the pipe line L4 is larger than the set pressure Pa of the spring 12a, and allows the flow of the pressurized oil from the pipe line L4 to the pipe line L3. When the pressure P4 in the pipe line L4 is below the set pressure Pa, it closes and interrupts the flow of the pressurized oil from the pipe line L4 to the pipe line L3. The positions of the variable throttle valve 11 and the counter balance valve 12 may be replaced.

2 is a diagram illustrating a configuration of the accumulator 13. The accumulator 13 reduces the pressure fluctuation of the pour cylinder 2 by the accumulating action, and here, a bladder type accumulator is used. In the bladder type accumulator 13, the gas of predetermined pressure Pb is enclosed in the shell 131 which is a container, and the gas chamber R1 and the oil chamber R2 are isolate | separated by the bladder 132. As shown in FIG. The oil outlet of the oil chamber R2 has a type in which the poppet 133 is mounted. In this case, when the bladder 132 is expanded when storing the accumulator, the bladder 132 is opened by the poppet 133. Protect the bottom of the

The hydraulic force P4 in the pipeline L4 acts on the accumulator 13. The pressure P4 fluctuates according to the pressure (bottom pressure) of the bottom chamber 2b of the buoy cylinder 2, and the bottom pressure is a load or a buoy cylinder acting on the buoy BM (FIG. 3) at the time of operation. It varies depending on the operating speed in (2). The fluctuation in the bottom pressure causes the pressure Pr (= P4) of the oil chamber R2 of the accumulator 13 to fluctuate, and the bladder 132 expands and contracts to absorb the vibration of the pour cylinder 2. .

At this time, if the pressure Pr of the oil chamber R2 is more than the gas sealing pressure Pb, the bladder 132 will not collide with the poppet 133 as shown to Fig.2 (a). On the other hand, when the pressure Pr of the oil chamber R2 is smaller than the sealing pressure Pb of gas, there exists a possibility that it may collide with the poppet 133 as shown to FIG. 2 (b). In view of this point, in this embodiment, the set pressure Pa of the spring 12a of the counter balance valve 12 of FIG. 1 is set larger than the sealing pressure Pb of the gas of the accumulator 13 (Pa > Pb).

The main operation of the vibration suppressing apparatus according to the first embodiment will be described. The hydraulic force of the bottom chamber 2b of the pour cylinder 2 acts on the accumulator 13 via the variable throttle valve 11, the conduit L3, the check valve 14, and the conduit L4. At this time, when the pressure P4 in the conduit L4 is greater than the set pressure Pa of the counter balance valve 12 (P4> Pa), the counter balance valve 12 is opened, and the accumulator oil in the accumulator 13 is increased. It flows from the pipeline L4 to the pipeline L3. In this case, since the pressure Pr of the oil chamber R2 of the accumulator 13 is larger than the gas filling pressure Pb, the bladder 132 does not collide with the poppet 133.

On the other hand, when the pressure P4 in the pipeline L4 decreases below the set pressure Pa (P4 ≤ Pa), the counter balance valve 12 is closed, and the flow of the hydraulic oil from the pipeline L4 to the pipeline L3 is reduced. This is prevented. As a result, the pressurized oil is confined in the conduit L4, and the pressure decrease in the oil chamber R2 can be prevented. As a result, the pressure Pr of the oil chamber R2 is prevented from becoming smaller than the gas encapsulation pressure Pb, and it is possible to prevent the bladder 132 from colliding with the poppet 133 due to the change in the hydraulic force. have.

In this manner, according to the first embodiment, the variable throttle valve 11, the counter balance valve 12, and the accumulator 13 are connected to each other in series with the bottom chamber 2b of the buoy cylinder 2, and the counter balance is performed. The set pressure Pa of the spring 12a of the valve 12 was set larger than the sealing pressure Pb of the gas of the accumulator 13. As a result, when the hydraulic pressure P4 acting on the accumulator 13 becomes equal to or less than the gas encapsulation pressure Pb, the counter balance valve 12 is closed, and discharge of the pressurized oil from the accumulator 13 is prevented. As a result, the bladder 132 can be prevented from colliding with the inside of the poppet 133 or the cell 131, and damage to the accumulator 13 can be prevented.

Second Embodiment

With reference to FIG. 3, FIG. 4, 2nd Embodiment of the vibration suppression apparatus of the hydraulic work machine which concerns on this invention is described.

The second embodiment differs from the first embodiment in that a break valve is provided in the buoy cylinder 2. FIG. 3: is an external side view of the hydraulic excavator which concerns on 2nd Embodiment, and has shown the structure mainly around the pour cylinder 2. As shown in FIG. 4 is a hydraulic circuit diagram showing a configuration of a vibration suppressing device according to a second embodiment. 4, illustration of the hydraulic pump 1, the direction control valve 3, etc. is abbreviate | omitted. In FIG. 3, FIG. 4, the same code | symbol is attached | subjected to the same part as FIG. 1, FIG. 2, and the difference with 1st Embodiment is mainly demonstrated below.

As shown in FIG. 3, the upper revolving structure 103 is mounted above the crawler type lower traveling body 101 so that it can turn via the revolving device 102. As shown in FIG. In addition to the cab 104, the upper swing structure 103 is provided with an engine chamber, a counterweight, and a hydraulic pump 1 and a direction control valve 3 shown in FIG. 1. In the front part of the upper pivot 103, the boom BM is axially supported so that rotation in the up-down direction is possible. The tip end (rod side end) of the buoy cylinder 2 is rotatably connected to the buoy BM, and the proximal end (cylinder tube side end) is rotatably connected to the upper pivot 103, and the buoy BM Is supported by the pour cylinder 2.

A break valve 15 is directly attached to the proximal end surface of the pour cylinder 2, and a counter balance valve 12, a variable throttle valve 11, and an accumulator 13 are directly attached to the break valve 15. have. On the proximal end surface of the pour cylinder 2, these hydraulic apparatuses are connected to each other by iron piping.

As shown in FIG. 4, the break valve 15 incorporates a pilot check valve 151, and the pressure oil inflow and outflow port p1 of the bottom chamber 2b of the pour cylinder 2 is a pilot check valve 151 and a pipe line. It is connected to the direction control valve 3 (FIG. 1) via L2. The pipeline 153 is branched from the pipeline 152 connecting the pilot check valve 151 and the port p1. The counter balance valve 12, the variable throttle valve 11, and the accumulator 13 are connected in series with the branch line 153, and the check valve 14 is connected in parallel with the counter balance valve 12. It is. In addition, the variable throttle valve 11 may be provided in the branch line 153 between the pipe line 152 and the counter balance valve 12.

The set pressure Pa of the spring 12a of the counter balance valve 12 is set larger than the gas encapsulation pressure Pb of the accumulator 13 similarly to the first embodiment. As a result, the pressure Pr of the oil chamber R2 of the accumulator 13 can be prevented from becoming smaller than the gas filling pressure Pb, and the bladder 132 in the accumulator is prevented from colliding with the poppet 133. can do.

The function of the break valve 15 is demonstrated. The pilot check valve 151 is converted by the pilot pressure by the operation of the operation lever 4. That is, the pilot check valve 151 is opened when the operation lever 4 is operated from the neutral position and the blowing pressure is applied to the pilot check valve 151. As a result, the pressure oil can flow out from the bottom chamber 2b, and the pour cylinder 2 can be degenerate in accordance with the operation of the operating lever 4. On the other hand, when the operation lever 4 is returned to the neutral position and operated, the operation of the pilot pressure on the pilot check valve 151 is stopped, and the pilot check valve 151 is closed. As a result, the outflow of the pressurized oil from the bottom chamber 2b is prevented, and the degeneracy of the cylinder 2 is prohibited.

By providing the break valve 15 as described above, when the operating oil leaks from the pipe line L2 due to damage of the pipe line L2 which is a hydraulic hose, the buoyant BM can be prevented from dropping rapidly. . In addition, regarding the performance of the breaking valve 15, even if the hydraulic hose connected to the bottom chamber 2b of the pour cylinder 2 is damaged by ISO standard, it is prescribed | regulated that the initial descent speed shall be 200 mm / sec or less. In this embodiment, this requirement can be satisfied.

As described above, in the second embodiment, since the break valve 15 is mounted on the outer surface of the buoy cylinder 2, the buoy BM drops sharply when the operating oil leaks from the pipeline L2. Can be prevented. Since not only the break valve 15 but also the counter balance valve 12 and the accumulator 13 are mounted on the outer surface of the pour cylinder 2, the positional relationship of these hydraulic devices can be kept constant during swelling. , The pipe is easy to handle.

Third Embodiment

With reference to FIGS. 5-7, the 3rd Embodiment of the vibration suppression apparatus of the hydraulic work machine which concerns on this invention is demonstrated.

In the third embodiment, the on-off valve is directly attached to the outer surface of the pour cylinder 2. FIG. 5 is a hydraulic circuit diagram showing the configuration of the vibration suppressing apparatus according to the third embodiment, and FIG. 6 is an enlarged view of a main part thereof. In addition, the same code | symbol is attached | subjected to the same part as FIG. 3, and the difference with 2nd Embodiment is mainly demonstrated below.

As shown in FIG. 5, a break valve 15 is provided in each of the left and right pairs of float cylinders 2 provided on the left and right sides of the buoy BM, and each break valve 15 connects the tuning pipe line L41. They are connected to each other via. The pipeline L42 branches from the tuning pipeline L41, and the variable throttle valve 11 and the accumulator 13 are connected to the tuning pipeline L41 via the branch pipeline L42. In addition, the variable throttle valve 11 may be omitted in the circuit of FIG. 5. The pipelines L41 and L42 are formed by a hydraulic hose.

As shown in FIG. 6, the break valve 15 has five ports p1-p5. The pilot operated check valve 151 is provided in the conduit 152 connecting the ports p1 and p4. The check valve 151 opens when the pour down pilot pressure acts on the port p5, and closes when the pour down pilot pressure stops. The throttle 154 is provided in the pipeline 153 which branches off from the pipeline 152 and reaches the port p2. Even if the conduits L41 and L42 connected to the port p2 are damaged by this throttle 154, the swelling speed is limited.

The break valve 15 is provided with a conduit 155 which branches back from the conduit 152 and reaches the port p3. The on-off valve 16 is directly attached to the port p3, and the port p3 is connected to the tuning line L41 via the on / off valve 16. That is, the opening / closing valve 16 is provided in the pipeline which bypasses the throttle 154. The pressure in the tuning pipe line L41, that is, the discharge oil from the accumulator 13, acts as a pilot pressure on the on / off valve 16. When the spring 16a of the on-off valve 16 is set to a predetermined set pressure Pc, and the pilot pressure is larger than this set pressure Pc, the open / close valve 16 is switched to the open position of the position (b). The port p3 communicates with the accumulator 13. When the pilot pressure is equal to or lower than the set pressure Pc, the open / close valve 16 is switched to the cutoff position at the position a, and the port p3 is cut off from the accumulator 13.

The spring set pressure Pc of the on-off valve 16 is set larger than the gas encapsulation pressure Pb of the accumulator 13. As a result, before the pressure Pr of the oil chamber R2 of the accumulator 13 drops to the gas encapsulation pressure Pb, the flow of pressure from the accumulator 13 to the conduit 155 is prevented and the oil chamber R2 is prevented. It is possible to prevent the pressure Pr from lowering than the gas filling pressure Pb. As a result, the bladder 132 can be prevented from colliding with the inside of the poppet 133 or the shell 131, and damage to the accumulator 13 can be prevented. In this case, when these hydraulic pressures are lowered due to damage to the pipelines L41 and L42 of the hydraulic hose, the opening / closing valve 16 is switched to the shutoff position (position) so that the pressure of the bottom chamber 2b is reduced. The oil can be prevented from flowing out from the port p3.

In the third embodiment, since the conduits L1 and L2 are formed of flexible hydraulic hoses, the accumulator 13 can be arranged as follows. 7 is an external side view of the hydraulic excavator according to the third embodiment. As shown in FIG. 7, the variable throttle 11 and the accumulator 13 are placed inside the upper swing body 103 rather than the surface of the pour cylinder 2. In addition, 17 is a coupling which connects the pipeline L41 and the pipeline L42. As a result, since the accumulator 13 of the high voltage component is not exposed to the outside, the accumulator 13 can be protected. Since the accumulator 13 is placed in the upper swing body 103, the appearance is also preferable. Since the bottom chambers 2b of the pair of buoy cylinders 2 are connected to each other by the tuning conduit L41, the movements of the cylinders 2 are synchronized with each other, so that the buoy BM can be smoothly driven. Since the accumulator 13 is connected to the tuning line L41 via the line L42, the circuit configuration can be simplified.

Fourth Embodiment

The 4th Embodiment of the vibration suppression apparatus of the hydraulic work machine which concerns on this invention with reference to FIG. 8, FIG. 9 is demonstrated.

In the fourth embodiment, an example in which a pilot check valve is provided in place of the on / off valve 16 will be described. 8 is a hydraulic circuit diagram showing an example thereof. In addition, the same code | symbol is attached | subjected to the same part as FIG. 5, FIG. 6, and the difference with 3rd Embodiment is mainly demonstrated below.

As shown in FIG. 8, the pilot check valve 18 is provided in the port p3 of the break valve 15 instead of the on-off valve 16. As shown in FIG. The hydraulic pressure in the tuning line L41 acts as a pilot pressure on the pilot check valve 18. The check valve 18 is opened by the pilot pressure, and the check valve 18 is closed when the pilot pressure stops. For this reason, when an oil leak occurs by the damage of pipeline L41, L42, since the check valve 18 is closed, the pressure oil of the bottom chamber 2b can be prevented from flowing out from the port p3.

9 is a hydraulic circuit showing another example in which the pilot check valve 18 is provided in the break valve 15. In FIG. 9, unlike the circuit of FIG. 8, the counter balance valve 12 and the check valve 14 shown in FIG. 1 are provided in the pipeline L42. Thereby, the pressure drop of the oil chamber R2 of the accumulator 13 is limited by the counter balance valve 12, and the collision of the bladder 132 and the poppet 133 can be prevented.

Moreover, in the said embodiment, the counter balance valve 12 and the opening / closing valve 16 are provided in the conduit connected to the accumulator 13, and the set pressure Pa of these springs 12a and 16a is accumulator 13 If the hydraulic pressure acting on the accumulator 13 is less than or equal to the gas encapsulation pressure Pb, it is closed and the hydraulic oil flowing from the accumulator 13 is cut off. May be anything. As long as it has the gas chamber R1 which expands and contracts by the hydraulic force acting on the accumulator 13, the structure of the accumulator 13 is not limited to the above-mentioned thing either. The circuit configuration of the vibration suppression device is not limited to the above as long as it comprises at least a shutoff valve and an accumulator.

When the pilot operating pressure applied to the pressure oil inflow and outflow port p1 of the bottom chamber 2b of the buoy cylinder 2 becomes below a predetermined value (for example, 0), the buoy cylinder 2 As long as the pilot operated check valve 151 is incorporated to block the outflow of the pressurized oil from the bottom chamber 2b, the break valve 15 may be of any configuration. For example, as shown in FIG. 10, you may provide the switching valve 157 converted by pilot operation pressure, and may open and close the pilot check valve 151 according to conversion of the switching valve 157. FIG. In FIG. 10, when the changeover valve 157 is changed to the position (a), only the flow of pressure oil from the conduit L2 through the check valve 158 to the conduit 152 is permitted, and the conduit ( The flow of pressurized oil to L2) is cut off. When the switching valve 157 is switched to the position (B) by the pilot operating pressure, the hydraulic pressure from the pipe line L2 passes through the pilot check valve 151, so that the pilot check valve 151 is opened and the pipe line 152 ), The flow of the pressurized oil to the pipeline L2 is permitted. That is, the pilot check valve of the present application includes not only the pilot operating pressure being directly acted on and converted, but also the pilot operating pressure being indirectly acted on via the switching valve 157 to be converted.

By operating the operating lever 4, the pilot operating pressure was output to operate the control valve 3, but the configuration of the operating portion may be any. In the said embodiment, although the vibration suppression apparatus 10 was applied to the drive circuit of the boom cylinder 2, it can apply also to the drive circuit of other hydraulic actuators, such as an arm cylinder. Although the example applied to the hydraulic excavator was demonstrated, it can also apply to other hydraulic work machines (for example, a crane). That is, the present invention is not limited to the vibration suppressing device of the hydraulic work machine of the embodiment as long as the features and functions of the present invention can be realized.

This application is based on Japanese Patent Application No. 2007-9256 (January 18, 2007), the contents of which are incorporated herein by reference.

Claims (7)

In the vibration suppression apparatus of the hydraulic working machine which is connected to the hydraulic actuator driven by the hydraulic oil from the hydraulic source via a pipeline, and suppresses the vibration of the hydraulic actuator, An accumulator having a gas chamber that expands and contracts by hydraulic pressure of the pressurized oil in the pipeline; And a shutoff valve which closes when the hydraulic force acting on the accumulator is equal to or lower than a set pressure of the gas enclosed in the gas chamber, and shuts off the hydraulic oil flowing from the accumulator. A pour cylinder for driving the work boom installed in the upper swing body by the hydraulic oil from the hydraulic source, A pilot operated check valve installed at the pressure oil inflow and outflow port of the bottom chamber of the buoy cylinder and blocking the outflow of the pressurized oil from the bottom chamber of the buoy cylinder when the pilot operating pressure applied to the buoy cylinder becomes less than a predetermined value; Built-in break valve, And a gas chamber which is connected to a branch line branched from a connecting line connecting the pilot operated check valve and the pressure oil inflow and outflow port of the bottom chamber of the boom cylinder, and expands and contracts by hydraulic pressure of the pressurized oil in the branch line. Accumulator, And a shutoff valve which closes when the hydraulic force acting on the accumulator is equal to or lower than a set pressure of the gas enclosed in the gas chamber, and shuts off the hydraulic oil flowing from the accumulator. The method of claim 2, The accumulator and the shutoff valve are vibration suppression devices of the hydraulic work machine, respectively, installed in the buoy. The method of claim 2, And said accumulator and said shut-off valve are respectively installed in said upper swing structure. The method of claim 4, wherein The pair of boolean cylinders are installed at the same time, the break valve is installed in each boolean cylinder, Branch circuits branched from a pair of connection pipes connecting the pilot operated check valve of each break valve and the pressure oil inflow and outflow port of the bottom chamber of each buoy cylinder are connected to each other via a throttle to form a tuning pipe. A pair of bypass conduits for bypassing the throttle and connecting the respective conduits and the accumulator, respectively; The accumulator is connected to the tuning conduit, The shut-off valve is a vibration suppressor of the hydraulic work machine, respectively provided in the pair of bypass pipe. The method of claim 5, The shutoff valve is an on-off valve, The on / off valve is opened when the hydraulic pressure is greater than the set pressure, and closed when the hydraulic force is equal to or less than the set pressure. Undercarriage, An upper swinging body installed on the lower traveling body via a turning device; A working front comprising at least the boolean, The vibration suppressing device according to any one of claims 2 to 6, A control valve for controlling the flow of the pressurized oil from the hydraulic source to the pour cylinder; And an operation unit for outputting the pilot operation pressure to operate the control valve.

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