KR100791105B1 - Increase in speed apparatus of boom speed of excavator - Google Patents

Abstract

In order to improve the workability, in case of complex work by operating the boom raising and turning drive of the excavator at the same time, the unskilled person can easily operate the working device by lowering the turning speed and relatively increasing the boom driving speed. ,

Excavator boom speed increasing apparatus according to an embodiment of the present invention, the first and second hydraulic pump,

A first actuator for the work device connected to the first hydraulic pump,

A second actuator connected to a second hydraulic pump and connected in series to form a pair;

A first control valve installed in a flow path between the first hydraulic pump and the first actuator, the first control valve controlling the start, stop, and direction change of the first actuator during switching;

A second control valve installed in a flow path between the second hydraulic pump and the second actuator and controlling the start, stop, and direction change of the second actuator during switching;

A third control valve installed in a flow path between the second hydraulic pump and the first actuator and for joining a part of the hydraulic oil of the second hydraulic pump to the first actuator during switching;

It is installed in the flow path between any selected actuator of the second actuator and the second control valve, and when driving only the second actuator, supplying the hydraulic oil of the second hydraulic pump to the selected actuator, and simultaneously driving the first and second actuators And a block valve for replenishing and supplying the hydraulic oil to be supplied to the selected actuator, which is switched according to a control signal input from the outside.

Heavy Equipment, Boom Speed Booster, Actuator, Slewing Motor, Combined Work

Description

Increase in speed apparatus of boom speed of excavator

1 is a side view of a typical excavator,

2 is a schematic view of a power generating unit for driving an excavator;

3 is a hydraulic circuit diagram for driving a boom and a swing motor of an excavator according to the prior art;

4 is a view for explaining the driving of the upper swing structure by the swing motor according to the prior art,

5 is a hydraulic circuit diagram of an excavator boom speed increasing apparatus according to an embodiment of the present invention;

6 is a view for explaining the driving of the upper swing structure by the swing motor according to an embodiment of the present invention,

7 is a graph showing the relationship between the turning angle and the bucket height in comparison with the prior art and the present invention when operating the boom raising and turning drive at the same time;

8 is a hydraulic circuit diagram of an excavator boom speed increasing apparatus according to another embodiment of the present invention;

9 is a view for explaining the driving of the upper swing structure by the swing motor according to another embodiment of the present invention.

* Explanation of symbols used in the main part of the drawing

One; Undercarriage

2,2a; 2nd Actuator (Swing Motor)

5; Upper pivot

8; 1st Actuator (Boom Cylinder)

16a; 1st hydraulic pump

16b; 2nd hydraulic pump

18; Control Valve (MCV)

22; 1st control valve

23; 2nd control valve

24; 3rd control valve

25,26,27,28,29,30,41,42; Euro

40; Block Valve

The present invention relates to an excavator boom speed increasing apparatus that enables the operation of the boom raising and the turning drive of heavy equipment at the same time, thereby increasing the boom driving speed and lowering the turning speed.

More specifically, in the case of complex operation by simultaneously operating the boom raising and turning drive of the excavator to improve the workability, the unskilled person can easily operate the work device by lowering the turning speed and relatively increasing the boom driving speed. To an excavator boom speed increaser.

As shown in FIG. 1, a general excavator includes a lower traveling body 1,

A drive mounted on the lower traveling body 1 and including a swing motor 2, a pinion gear 3 fixed to the swing motor 2, an internal gear 4 engaged with the pinion gear 3, and the like. An upper pivot 5 which is rotated in the left or right direction by the means;

The cab 6 and the engine compartment 7 mounted on the upper swing body 5,

A boom 9 mounted to the upper swinging body 5 and driven by the boom cylinder 8, an arm 11 driven by the arm cylinder 10, and a bucket driven by the bucket cylinder 12. A work device 14 comprising 13;

It is provided with a counterweight 15 mounted behind the upper swinging body 5 and having a weight body (not shown) embedded therein to maintain the balance of the equipment during operation.

As shown in FIG. 2, the power generating unit for driving the excavator is driven by the engine 16 and the engine 16 to supply hydraulic oil to the actuators A; 8, 10, 12 of the work device 14. And a control valve 18 (referring to MCV) installed in the flow path between the hydraulic pump 17 and the actuator A and controlling the hydraulic oil supplied to the actuator A.

In the figure, reference numeral 19 denotes a radiator, 20 denotes an oil cooler for cooling the returned oil, and 21 denotes a hydraulic tank.

As shown in FIG. 3, the hydraulic circuit driving the boom and the swing motor according to the prior art includes: first and second hydraulic pumps 16a and 16b connected to the engine 16;

A first actuator 8 (referring to a boom cylinder) connected to the first hydraulic pump 16a,

A second actuator 2 (referring to a swing motor) connected to the second hydraulic pump 16b,

The first control valve 22 is installed in the flow paths 25 and 26 between the first hydraulic pump 16a and the first actuator 8 and controls the start, stop, and direction change of the first actuator 8 at the time of switching. )Wow,

A second control valve 23 installed in the flow paths 29 and 30 between the second hydraulic pump 16b and the second actuator 2 to control the start, stop and direction change of the second actuator 2 during switching; )Wow,

Flow paths 27 and 28 between the second hydraulic pump 16b and the first actuator 8 (in this case, the flow paths 27 and 28 communicate with flow paths 25 and 26 connected to the first control valve 22). And a third control valve 24 for joining the hydraulic oil of the second hydraulic pump 16b to the first actuator 8 at the time of switching.

A) Driving to raise and lower the boom will be described with reference to FIG.

When the control signal is input by the user to the right end of the first control valve 22, the internal spool is switched to the left in the drawing (referring to the "a" position). Since the hydraulic oil discharged from the first hydraulic pump 16a passes through the first control valve 22 and the oil passage 25 and is supplied to the large chamber of the first actuator 8, the boom 9 is raised. At this time, the hydraulic oil discharged from the first actuator 8 passes through the flow passage 26 and the first control valve 22 to be returned to the hydraulic tank.

On the contrary, when the first control valve 22 is switched to the right in the drawing (referring to the "b" position), the hydraulic fluid discharged from the first hydraulic pump 16a is transferred to the first control valve 22. ) And the flow path 26 are supplied to the small chamber of the first actuator 8 so that the boom 9 is lowered. At this time, the hydraulic oil discharged from the first actuator 8 passes through the flow passage 25 and the first control valve 22 to be returned to the hydraulic tank.

B) A drive for rotating the upper swing structure will be described with reference to FIG.

When the control signal is input by the user to the left end of the second control valve 23, the inner spool is switched to the right in the drawing (referring to the "e" position). Since the hydraulic oil discharged from the second hydraulic pump 16b passes through the second control valve 23 and the flow path 30 and is supplied to the second actuator 2, the turning motor 2 is rotated.

For this reason, the upper swinging body 5 is rotated by mutual engagement between the pinion gear 3 fixed to the swinging motor 2 and the internal gear 4 fixed to the upper swinging body 5. At this time, the hydraulic oil discharged from the second actuator 2 passes through the flow path 29 and the second control valve 23 and is returned to the hydraulic tank.

C) The operation of increasing the boom driving speed will be described with reference to FIG. 3.

During operation, when the operation speed of the boom 9 is increased, when the control signal is input to the left end of the third control valve 24 by the user, the internal spool is switched to the right in the drawing ("c" position). Switch to). The hydraulic oil discharged from the second hydraulic pump 16b passes through the third control valve 24 and the flow paths 27 and 25 and is supplied to the first actuator 8. That is, part or all of the hydraulic oil discharged from the second hydraulic pump 16b is joined to the first actuator 8 side, thereby increasing the boom 9 driving speed.

The hydraulic oil discharged from the first actuator 8 is returned to the hydraulic tank through the flow path 26 and the first control valve 22, and at the same time to the hydraulic tank through the flow path 28 and the third control valve 24. Is returned. In this case, the first control valve 22 is first opened and the third control valve 24 is later opened.

D) Simultaneously driving the boom lift and the upper swing rotation will be described with reference to FIG.

In the case of the loading operation using an excavator, after excavating the earth and sand with the bucket 13, the boom (9) is raised, and the operation of dumping the earth and sand into the dump trucks, etc. by rotating the upper swinging body (5). Repeat. At this time, the driver simultaneously performs an operation of raising the boom 9 and an operation of rotating the upper swing body 5 to reduce cycle time.

At this time, the load is generated in the bucket 13 loaded with the earth and sand, the ascending speed of the boom 9 is lowered, the pressure of the upper swing body 5 is increased, the rotational speed is relatively faster. As a result, the driver waits for the time when the boom 9 rises, thereby artificially decelerating the rotation speed of the upper swing body 5. In this way, a combination of operation by simultaneously operating the boom raising and the turning drive requires a lot of work experience and skilled operators.

According to one embodiment of the present invention, when operating a boom lift and swing drive of the excavator at the same time to perform a composite work, the operation speed of the work device is easy to improve the workability by lowering the swing speed and relatively high boom drive speed Related to the excavator boom speed increaser.

According to one embodiment of the present invention, when operating the boom raising and the turning drive of the excavator at the same time, the speed of excavator boom speed is increased to provide convenience to the driver because there is not enough working experience and can be easily operated by an inexperienced person. Associated with the device.

Excavator boom speed increasing apparatus according to an embodiment of the present invention, the first and second hydraulic pump,

A first actuator for the work device connected to the first hydraulic pump,

A second actuator connected to a second hydraulic pump and connected in series to form a pair;

A first control valve installed in a flow path between the first hydraulic pump and the first actuator, the first control valve controlling the start, stop, and direction change of the first actuator during switching;

A second control valve installed in a flow path between the second hydraulic pump and the second actuator and controlling the start, stop, and direction change of the second actuator during switching;

A third control valve installed in a flow path between the second hydraulic pump and the first actuator and for joining a part of the hydraulic oil of the second hydraulic pump to the first actuator during switching;

It is installed in the flow path between any selected actuator of the second actuator and the second control valve, and when driving only the second actuator, supplying the hydraulic oil of the second hydraulic pump to the selected actuator, and simultaneously driving the first and second actuators And a block valve for replenishing and supplying the hydraulic oil to be supplied to the selected actuator, which is switched according to a control signal input from the outside.

According to a preferred embodiment, as a control signal for switching the above-described block valve, various means as follows are possible.

A) Pilot signal pressure is used to switch the third control valve for extendingly driving the first actuator.

B) An electrical signal is used to switch the third control valve to extend and drive the first actuator.

C) It is switched to physical manipulation by worker's hand or foot.

D) Pilot signal pressure for switching the first control valve for extendingly driving the first actuator is used.

E) An electrical signal is used to switch the first control valve to extend-drive the first actuator.

The first actuator described above is a boom cylinder, and the second actuator is a swing motor.

Excavator boom speed increasing apparatus according to another embodiment of the present invention, the first and second hydraulic pump,

A first actuator for the work device connected to the first hydraulic pump,

A variable displacement second actuator connected to a second hydraulic pump,

A first control valve installed in a flow path between the first hydraulic pump and the first actuator, the first control valve controlling the start, stop, and direction change of the first actuator during switching;

A second control valve installed in a flow path between the second hydraulic pump and the second actuator and controlling the start, stop, and direction change of the second actuator during switching;

A third control valve installed in a flow path between the second hydraulic pump and the first actuator and for joining a part of the hydraulic oil of the second hydraulic pump to the first actuator during switching;

It is installed in the second actuator and is supplied according to the control signal input from the outside during the complex operation for simultaneously driving the first and second actuators, and a part of the hydraulic oil supplied from the second hydraulic pump to the second actuator is supplemented and supplied to the first actuator. A variable capacity mechanism is provided.

According to a preferred embodiment, as a control signal for driving the above-mentioned capacitive variable mechanism, various means as follows are possible.

A) Pilot signal pressure is used to switch the third control valve for extendingly driving the first actuator.

B) An electrical signal is used to switch the third control valve to extend and drive the first actuator.

C) Pilot signal pressure is used to switch the first control valve for extendingly driving the first actuator.

D) An electrical signal is used to switch the first control valve to extend drive the first actuator.

The first actuator described above is a boom cylinder, and the second actuator is a variable displacement swing motor.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings, which are intended to describe in detail enough to enable those skilled in the art to easily practice the invention, and therefore It is not intended that the technical spirit and scope of the present invention be limited.

As shown in FIG. 5, the excavator boom speed increasing apparatus according to an embodiment of the present invention includes: first and second hydraulic pumps 16a and 16b connected to the engine 16;

A first actuator 8 (referring to a boom cylinder) for a work device connected to the first hydraulic pump 16a,

A second actuator (2, 2a) (referred to as a turning motor) connected to the second hydraulic pump (16b) and connected in series;

It is installed in the flow paths 25 and 26 between the first hydraulic pump 16a and the first actuator 8 and is switched when inputting a control signal from the outside to control the start, stop and direction change of the first actuator 8. The first control valve 22,

It is installed in the flow paths 29 and 30 between the second hydraulic pump 16b and the second actuators 2 and 2a, and is switched when the control signal is input from the outside to start, stop and start the second actuators 2 and 2a. A second control valve 23 for controlling the change of direction;

Flow paths 27 and 28 between the second hydraulic pump 16b and the first actuator 8 (in this case, the flow paths 27 and 28 communicate with flow paths 25 and 26 connected to the first control valve 22). A third control valve (24) installed at the head) and switched when the control signal is input from the outside to join a part of the hydraulic oil of the second hydraulic pump (16b) to the first actuator (8);

The flow paths 41 and 42 between any of the selected actuators 2a and the second control valve 23 among the second actuators 2 and 2a (at this time, the flow paths 41 and 42 are flow paths connected to the second actuator 2). (29, 30) in communication with), supplying the hydraulic oil of the second hydraulic pump (16b) to the selected actuator (2a) when driving only the second actuator (2, 2a), the first, second actuator (8) Block valve 40 for supplying hydraulic oil to be supplied to the first actuator 8 to be supplied to the second actuator 2a which is switched according to the control signal Pa input from the outside during the complex operation of simultaneously driving 2 and 2). ).

In this case, as the control signal Pa for switching the aforementioned block valve 40, a pilot signal pressure or an electrical signal for switching the third control valve 24 to extend-drive the first actuator 8 may be used. .

The block valve 40 described above may be switched to physical manipulation by the operator's hand or foot.

As the control signal Pa for switching the above-described block valve 40, a pilot signal pressure or an electrical signal for switching the first control valve 22 to extend-drive the first actuator 8 may be used.

On the other hand, the reference numerals for the parts that are applied substantially the same as shown in Figure 3 are the same as those of Figure 3, and detailed description of their structure and operation will be omitted.

Hereinafter, with reference to the accompanying drawings an example of the use of the excavator boom speed increasing apparatus according to an embodiment of the present invention will be described in detail.

As shown in Fig. 5, when the user switches the first control valve 22, the hydraulic oil discharged from the first hydraulic pump 16a drives the first actuator 8 (referring to the boom cylinder). It is shown in FIG. 3 to switch the third control valve 24 to join a portion of the hydraulic oil discharged from the second hydraulic pump 16b to the first actuator 8 to increase the driving speed of the first actuator 8. The detailed description thereof will be omitted since they are substantially the same as the above.

A) Driving the upper swing structure will be described with reference to FIGS. 5 and 6.

When the control signal is input by the user to the left end of the second control valve 23, the internal splines are switched to the right in the drawing (referring to the "e" position). A part of the hydraulic oil discharged from the second hydraulic pump 16b passes through the second control valve 23 and the flow path 30 and is supplied to the second actuator 2. At the same time, a part of the hydraulic oil discharged from the second hydraulic pump 16b sequentially turns the second control valve 23, the flow paths 29 and 42, and the block valve 40 (the state switched to the "a" position). It passes and is supplied to the 2nd actuator 2a.

Accordingly, the upper pivot 5 is rotated by the reaction force by mutual engagement of the pinion gear 3 and the internal gear 4 which are rotated by the driving force output from the pair of swing motors 2 and 2a. You can.

B) Rotating the boom and the upper pivot at the same time to reduce the cycle time during operation will be described with reference to FIG.

When the user inputs a control signal Pa (for example, a pilot signal pressure or an electrical signal) to the right end of the block valve 40, the internal spool is switched to the left in the drawing ("b" position). Switch to). At this time, the valve spring 40a is compressed.

Since the input side flow paths 41 and 42 of the block valve 40 are blocked, the hydraulic oil discharged from the second hydraulic pump 16b is supplied only to the second actuator 2 through the flow paths 29 and 30. . That is, the upper swinging body 5 is rotated only by the driving force transmitted from the second actuator 2 of the pair of second actuators 2 and 2a.

At this time, the second actuator 2a revolves by the communication circuit in the block valve. Therefore, since the torque for driving the swinging body is reduced (half-half when the second actuators 2 and 2a have the same capacity), the acceleration of the swinging body is reduced, and the speed increase is suppressed. Therefore, since the rotation speed of the second actuator 2 is reduced, the required flow rate is reduced. As the decrease, the flow rate supplied to the first actuator 8 side increases, and the driving speed increases.

As shown in Fig. 7, the upper swinging body 5 is typically pivoted at an angle of 90 degrees during the loading operation of dumping earth and sand or the like into a dump truck or the like using an excavator. As a result of the practical test, in the conventional method, when the upper swinging body 5 was swiveled at an angle of 90 ° after the excavation, the height of the bucket 13 rising above the loading box was 3 m (curve "a"). Shown).

On the other hand, in the case of applying the present invention, as shown by the curve "b", the height of the bucket 13, which comes up to the loading box when rotating the upper swing body 5 by 90 ° after the excavation showed 5m. As a result, when operating the boom raising and the turning drive at the same time in order to increase the work efficiency, the boom (9) ascending speed is increased and the rotation speed of the upper turning body (5) is relatively reduced, so that the driver of the upper turning body (5) It was confirmed that the operation of artificially slowing down the rotation speed became unnecessary.

As shown in Figure 8 and 9, the excavator boom speed increasing apparatus according to another embodiment of the present invention, the first and second hydraulic pumps (16a, 16b) connected to the engine 16,

A first actuator 8 (referring to a boom cylinder) for a work device connected to the first hydraulic pump 16a,

A variable displacement second actuator 2b (referring to a swing motor) connected to the second hydraulic pump 16b;

It is installed in the flow paths 25 and 26 between the first hydraulic pump 16a and the first actuator 8 and is switched when inputting a control signal from the outside to control the start, stop and direction change of the first actuator 8. The first control valve 22,

It is installed in the flow paths 29 and 30 between the second hydraulic pump 16b and the second actuator 2b, and is switched when inputting a control signal from the outside to control the start, stop and direction change of the second actuator 2b. The second control valve 23,

Flow paths 27 and 28 between the second hydraulic pump 16b and the first actuator 8 (in this case, the flow paths 27 and 28 communicate with the flow paths 25 and 26 provided with the first control valve 22). A third control valve 24 installed at the outside and switched when inputting a control signal from the outside to join a part of the hydraulic oil of the second hydraulic pump 16b to the first actuator 8;

It is installed in the second actuator 2b and driven according to the control signal Pa input from the outside during the compound work for simultaneously driving the first and second actuators 8 and 2b (swash plate of the second actuator 2b). The discharge angle is adjusted by controlling the tilt angle.) A variable capacity mechanism 2c for replenishing and supplying a part of the hydraulic oil to be supplied from the second hydraulic pump 16b to the second actuator 2b to the first actuator 8 (example) A piston is used).

At this time, the above-described variable displacement second actuator 2b has a maximum capacity output mode for outputting maximum torque and a minimum capacity discharge mode for outputting torque of about 50% by the drive of the capacity variable mechanism 2c.

On the other hand, as the control signal Pa for driving the above-mentioned displacement variable mechanism 2c, a pilot signal pressure or an electrical signal for switching the third control valve 24 to extend-drive the first actuator 8 can be used. have.

As the control signal Pa for driving the above-mentioned capacitance varying mechanism 2c, a pilot signal pressure or an electrical signal for switching the first control valve 22 to extend-drive the first actuator 8 may be used.

In this case, the configuration except for the variable capacitance type second actuator 2b and the variable capacitance mechanism 2c described above is substantially the same as the embodiment of the present invention shown in FIG. Reference numerals are the same, and detailed descriptions of their configuration and operation are omitted.

Hereinafter, with reference to the accompanying drawings an example of the use of an excavator boom speed increasing apparatus according to another embodiment of the present invention will be described in detail.

As shown in FIGS. 8 and 9, the above-described first control valve 22 is switched to drive the first actuator 8 with hydraulic oil supplied from the first hydraulic pump 16a to lift the boom. Lower The upper control body is rotated by switching the second control valve 23 to drive the variable displacement second actuator 2b by the hydraulic oil supplied from the second hydraulic pump 16b. At this time, as the third control valve 24 is switched to supply a part of the hydraulic oil from the second hydraulic pump 16b to the first actuator 8, the boom raising speed can be increased.

On the other hand, in order to reduce the cycle time during the loading operation using the excavator works by driving the boom rise and the upper swing structure at the same time. At this time, the boom lifting speed is lowered due to the load on the bucket, and the rotation speed of the upper swing structure is relatively high. This requires control to artificially slow down the rotational speed of the upper swing body.

That is, the above-mentioned first control valve 22 is operated to supply hydraulic oil from the first hydraulic pump 16a to the first actuator 8 to raise the boom. At the same time, the second control valve 23 is operated to supply hydraulic oil from the second hydraulic pump 16b to the second actuator 2b.

Therefore, the interlocking operation of the pinion gear 3 and the internal gear 4 rotated by the driving force output from the second actuator 2b causes the upper swing body 5 to rotate by the reaction force to carry out the loading operation. Can be done.

At this time, in order to increase the speed of the boom, the control signal Pa (for example, a pilot signal pressure or an electrical signal for switching the first control valve 22 or the third control valve 24) is applied to the second actuator 2b. In the case of inputting into the variable capacity mechanism 2c provided in the above), the second actuator 2b is switched to the minimum capacity discharging mode.

Therefore, the torque of the 2nd actuator 2b becomes small, and the rotation speed of an upper swing body is reduced. This reduces the amount of hydraulic oil supplied from the second hydraulic pump 16b required for the rotation of the upper swing body. Since the hydraulic oil of the reduced second hydraulic pump 16b is replenished to the first actuator 8, the boom raising speed is increased.

That is, during the loading operation, the boom ascending speed becomes faster and the rotation speed of the upper swing structure is relatively slow. Therefore, when the upper swing structure is rotated 90 degrees (swing to dump the soil loaded in the bucket into the dump truck) It was confirmed that the height rose from the conventional 3m (shown by curve "a" in FIG. 7) to 5m (shown by curve "b" in FIG.

Therefore, during the loading operation, the driver does not need an operation to artificially slow down the rotational speed of the upper swing structure, and thus the operation is easy.

As described above, the excavator boom speed increasing apparatus according to an embodiment of the present invention has the following advantages.

In the case of complex operation by operating the boom raising and the turning drive of the excavator at the same time, the cycle time can be reduced by improving the turning speed and increasing the boom driving speed relatively, thereby improving work efficiency.

In addition, when operating the boom lift and the swing drive of the excavator at the same time, there is not enough working experience and can be easily operated by an inexperienced operator to provide convenience to the driver.

Claims (13)

First and second hydraulic pumps; A first actuator for a work device connected to the first hydraulic pump; A second actuator connected to the second hydraulic pump and connected in series to form a pair; A first control valve installed in a flow path between the first hydraulic pump and the first actuator and controlling the start, stop, and direction change of the first actuator during switching; A second control valve installed in a flow path between the second hydraulic pump and the second actuator and controlling the start, stop, and direction change of the second actuator during switching; A third control valve installed in a flow path between the second hydraulic pump and the first actuator and for joining a part of the hydraulic oil of the second hydraulic pump to the first actuator during switching; And The combined operation is installed in the flow path between any one of the selected actuator and the second control valve, supplying the hydraulic oil of the second hydraulic pump to the selected actuator when driving only the second actuator, and simultaneously driving the first and second actuators Excavator boom speed increasing apparatus characterized in that it comprises a block valve for supplying the hydraulic fluid to be supplied to the first actuator to be supplied to the selected actuator is switched in accordance with the control signal input from the outside. First and second hydraulic pumps; A first actuator for a work device connected to the first hydraulic pump; A variable displacement second actuator connected to the second hydraulic pump; A first control valve installed in a flow path between the first hydraulic pump and the first actuator and controlling the start, stop, and direction change of the first actuator during switching; A second control valve installed in a flow path between the second hydraulic pump and the second actuator and controlling the start, stop, and direction change of the second actuator during switching; A third control valve installed in a flow path between the second hydraulic pump and the first actuator and for joining a part of the hydraulic oil of the second hydraulic pump to the first actuator during switching; And A part of the hydraulic oil installed in the second actuator and driven according to a control signal input from the outside during the combined operation of simultaneously driving the first and second actuators and supplied to the second actuator from the second hydraulic pump; Excavator boom speed increaser, characterized in that it comprises a variable capacity mechanism to supplement the supply. The method of claim 1, wherein the control signal for switching the block valve, And a pilot signal pressure for switching a third control valve for extendingly driving the first actuator. The method of claim 1, wherein the control signal for switching the block valve, And an electrical signal for switching the third control valve for extendingly driving the first actuator. The excavator boom speed increasing apparatus according to claim 1, wherein the block valve is switched by physical operation by an operator. The method of claim 1, wherein the control signal for switching the block valve, And a pilot signal pressure for switching said first control valve for extendingly driving said first actuator. The method of claim 1, wherein the control signal for switching the block valve, And an electrical signal for switching the first control valve to extend and drive the first actuator. The apparatus of claim 1, wherein the first actuator is a boom cylinder, and the second actuator is a swing motor. The control signal for driving the variable capacitance mechanism according to claim 2, And a pilot signal pressure for switching a third control valve for extendingly driving the first actuator. The control signal for driving the variable capacitance mechanism according to claim 2, Excavator boom speed increasing apparatus, characterized in that the electrical signal for switching the third control valve for extending the first actuator is used. The control signal for driving the variable capacitance mechanism according to claim 2, And a pilot signal pressure for switching said first control valve for extendingly driving said first actuator. The control signal for driving the variable capacitance mechanism according to claim 2, And an electrical signal for switching the first control valve to extend and drive the first actuator. The excavator boom speed increasing apparatus according to claim 2, wherein the first actuator is a boom cylinder, and the second actuator is a variable displacement swing motor.

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