JP2011157751A - Hydraulic work machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic work machine enabling an operator to immediately know whether the operating condition of the work being actually performed is a condition with good energy efficiency or not by observing a lamp display part. <P>SOLUTION: This hydraulic work machine includes a main controller 35 comprising an engine torque calculation part 35a for obtaining an engine torque related to a work performed at present and an energy efficiency determination part 35b for determining whether an operation for a work at present is performed with a good energy efficiency or not by driving a load body 33 based on the engine torque obtained by the engine torque calculation part 35a and a target engine speed output from an engine control dial 19. The main controller performs a processing to display the result of the determination by the energy efficiency determination part 35b to the lamp display part 21a of a monitor 21. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a hydraulic working machine such as a hydraulic excavator provided with a display unit capable of displaying information on fuel efficiency.

  There exists a thing shown by patent document 1 as this type of prior art. This prior art includes an engine, a rotation sensor that commands a target rotational speed of the engine, that is, a target rotational speed command means, and a variable displacement hydraulic pump that is driven by the engine. Although not shown in this Patent Document 1, this type of construction machine, that is, a hydraulic working machine, is provided with a main relief valve that regulates the maximum pressure of the hydraulic oil discharged from the variable displacement hydraulic pump. . In addition, the prior art disclosed in Patent Document 1 includes a hydraulic actuator that is operated by pressure oil discharged from a variable displacement hydraulic pump, and a working machine or working device that includes a boom, an arm, and the like that are driven by the hydraulic actuator, And a load body including a swivel body and the like. Furthermore, this prior art includes a monitor device that can display information on fuel efficiency, that is, a display unit, in a driver's cab provided in the turning body. On the display unit, an operation for improving the fuel efficiency is displayed as a sentence and a message.

  Although different from the hydraulic working machine that is the subject of the present invention, Patent Document 2 discloses an invention in which an advice is displayed so that the vehicle is in a driving state in which the fuel efficiency is improved by lighting a lamp. Has been.

JP 2005-98073 A JP 2008-88844 A

  The prior art disclosed in Patent Document 2 described above is designed to look at fuel efficiency in the driving state of the engine. However, in a hydraulic working machine as the subject of the present invention, as an element for measuring fuel efficiency, In addition to the engine driving state that directly affects fuel efficiency, there is an operating state of a load body including a working device that indirectly affects fuel efficiency. Therefore, it is basically impossible to adopt the concept of looking at fuel efficiency only by the driving state of an engine as in a car.

  The prior art disclosed in Patent Document 1 described above merely displays an operation for improving the fuel efficiency on the display unit as text and a message, and the driving state related to the work actually performed is the fuel efficiency. There is a problem that the operator cannot immediately know whether or not the driving state is good.

  The present invention has been made based on the above-described prior art, and an object of the present invention is to allow an operator to immediately know whether or not the driving state related to the work actually performed is a driving state with good fuel efficiency. It is to provide a hydraulic working machine.

  In order to achieve this object, a hydraulic working machine according to the present invention includes an engine, target rotational speed command means for commanding a target rotational speed of the engine, a variable displacement hydraulic pump driven by the engine, and a variable displacement hydraulic pump. A main relief valve that regulates the maximum pressure of the pressure oil discharged from the displacement hydraulic pump, a hydraulic actuator that operates by the pressure oil discharged from the variable displacement hydraulic pump, and a load that includes a working device driven by the hydraulic actuator A hydraulic working machine having a display unit capable of displaying information on fuel efficiency, an engine torque calculation unit for obtaining an engine torque related to the work actually performed, and an engine torque calculation unit And the target engine speed output from the target engine speed command means. A fuel efficiency determination unit that determines whether or not the driving state relating to the work actually performed by driving the load body is a driving state with high fuel efficiency, and the determination result in the fuel efficiency determination unit Is provided with a control device that performs a process of displaying the image on the display unit.

  In the hydraulic working machine according to the present invention configured as described above, the fuel efficiency determination unit of the control device outputs the engine torque related to the work actually performed, which is calculated by the engine torque calculation unit, and the target rotational speed command means. Based on the target engine speed related to the work actually being performed and whether or not the driving state related to the work actually being performed is a fuel-efficient driving state. By looking at the display on the display unit, it is possible to confirm at a glance whether the driving state related to the work actually performed is good or bad in fuel efficiency. That is, according to the present invention, the control device includes an engine torque calculation unit and a fuel efficiency determination unit, and a display unit that displays a determination result in the fuel efficiency determination unit. The operator can immediately know whether or not the driving state related to the work actually performed including both elements of the operating state of the load body including the driving body is a driving state with high fuel efficiency.

  Further, the hydraulic working machine according to the present invention includes, in the above invention, an operation detection unit that detects an operation of the load body, and the control device detects the load body based on a detection result of the operation detection unit. An operation determining unit that determines whether the operation does not adversely affect fuel efficiency, and the controller determines that the operation of the load body is an operation that does not adversely affect the fuel efficiency in the operation determining unit. At this time, it is characterized in that a process for displaying on the display section that it can be regarded as a driving state with good fuel efficiency is performed. The present invention configured as described above can prevent the operator from being aware of the fuel consumption driving when performing the work by the operation of the load body that does not adversely affect the fuel efficiency.

  Further, the hydraulic working machine according to the present invention includes, in the above invention, operation detection means for detecting the operation of the main relief valve, and the control device is configured to detect the main relief based on a detection result of the operation detection means. A relief operation determining unit that determines whether or not the valve has operated, and the control device assumes that the main relief valve has been operated by the relief operation determining unit and that the operating state is not fuel efficient. It is characterized by performing a process of displaying on the display unit what can be done. The present invention configured as described above can require the operator to be aware of fuel-efficient driving when the main relief valve is operated, even if the operation has been performed in a fuel-efficient driving state.

  The hydraulic working machine according to the present invention further comprises stroke detection means for detecting that the hydraulic actuator has reached a stroke end in the invention, and the control device is based on a detection result of the stroke detection means. A stroke end determination unit that determines whether or not the hydraulic actuator has reached a stroke end, and the control device determines fuel efficiency when the stroke end determination unit determines that the hydraulic actuator has reached the stroke end. The present invention is characterized in that a process for displaying on the display section that it can be assumed that the driving state is not good is performed. According to the present invention configured as described above, when the hydraulic actuator reaches the stroke end, the operator is required to be aware of fuel efficiency driving even if the operation has been performed in a fuel efficient operating state until then. Can do.

  Further, the hydraulic working machine according to the present invention includes, in the above invention, a cab in which the target rotational speed command means is disposed and a monitor installed in the cab, and the display unit is provided in the monitor. It is characterized by comprising a lamp display section provided. In the present invention configured as described above, for example, the lamp display unit can be turned on when the driving state is high in fuel efficiency, and the lamp display unit can be turned off when the driving state is low in fuel efficiency. That is, the operator can immediately determine whether the driving state related to the work actually performed is a fuel-efficient driving state or a bad driving state by observing whether the lamp display part of the monitor is turned on or off. I can know. Therefore, when the lamp display unit is in the off state, it is possible to ask the operator to be aware of fuel-efficient driving.

  The present invention provides an engine torque calculation unit for obtaining an engine torque related to a work actually performed, an engine torque obtained by the engine torque calculation unit, and an engine target rotation number output from a target rotation number command means. And a fuel efficiency determination unit for determining whether or not the driving state related to the work actually performed by driving the load body is a driving state with good fuel efficiency, and the determination in the fuel efficiency determination unit Since the control device for performing the process of displaying the result on the display unit is provided, the operation state related to the work actually performed including both elements of the engine drive state and the operation state of the load body including the work device is provided. The operator can immediately know from the display on the display section whether or not the driving state has good fuel efficiency. Therefore, it is possible to make the operator more aware of fuel-efficient driving than in the past, which greatly contributes to the realization of energy saving.

1 is a side view showing a hydraulic excavator that is an embodiment of a hydraulic working machine according to the present invention. It is a top view which shows the inside of the cab with which the hydraulic excavator which concerns on this embodiment is equipped. It is a figure which expands and shows the switch box with which the cab shown in FIG. 2 is equipped. It is a block diagram which shows the engine and hydraulic control system with which the hydraulic excavator which concerns on this embodiment is equipped. It is a characteristic view which shows the relationship between the switching position of the engine control dial obtained with the hydraulic shovel which concerns on this embodiment, and the rotation speed of an engine. It is a figure which shows the area | region R with good fuel efficiency set by the control apparatus with which the hydraulic excavator which concerns on this embodiment is equipped.

  Embodiments of a hydraulic working machine according to the present invention will be described below with reference to the drawings.

  One embodiment of the hydraulic working machine according to the present invention is composed of, for example, a hydraulic excavator. As shown in FIG. 1, this hydraulic excavator includes a traveling body 1, a revolving body 2 disposed on the traveling body 1, and a working device 3 attached to the revolving body 2 so as to be rotatable in the vertical direction. I have. The work device 3 includes a boom 4 attached to the revolving structure 2, an arm 5 attached to the tip of the boom 4, a bucket 6 attached to the tip of the arm 5, a boom cylinder 7 that operates the boom 4, and an arm 5. An arm cylinder 8 for operating the bucket 6 and a bucket cylinder 9 for operating the bucket 6.

  On the swivel body 2 described above, the cab 10 is disposed at the front position, and the counterweight 11 that secures the weight balance is disposed at the rear position, and between the cab 10 and the counterweight 11. In other words, an engine chamber 12 in which an engine, a variable displacement hydraulic pump, and the like are stored, which will be described later, is disposed.

  As shown in FIG. 2, a driver's seat 13 on which an operator sits is disposed in the operator's cab 10, and a front side position of the operator's cab 13 is a pair of left and right motors (not shown) that drives the traveling body 1. A right travel lever 14 and a right travel pedal 14a for operating the right travel motor, and a left travel lever 15 and a left travel pedal 15a for operating the left travel motor are arranged. An operation device 16 for operating the boom cylinder 7 and the bucket cylinder 9 is arranged at the right side position of the driver's seat 13, and the unillustrated turn for turning the arm cylinder 8 and the swing body 2 is placed at the left side position of the driver's seat 13. An operating device 17 for operating the motor is arranged. Further, a monitor 21 capable of various displays including drive information and the like related to the hydraulic excavator is disposed at the right front position of the driver's seat 13.

  Further, a switch box 18 is disposed in the vicinity of the operation device 16 located on the right side of the driver's seat 13. As shown in FIG. 3, the switch box 18 is provided with a speed command means for commanding a reference target speed NM of an engine, which will be described later, for example, an engine control dial 19 and a work mode switch 20. The work mode switch 20 corresponds to a mode during heavy load work, a high power mode switching position 20a for maintaining the target engine speed at the maximum torque target engine speed as indicated by the engine speed characteristic N1 in FIG. Corresponding to the mode at the time of operation, the target engine speed is maintained at a target engine speed slightly lower than the maximum torque target engine speed as shown by the engine speed characteristic N2 in FIG. 5, and fuel efficiency is improved. Corresponding to the eco mode to be performed, the target engine speed is set to a predetermined low target engine speed NS lower than the reference target engine speed NM in the high power mode and the normal mode as shown by the engine speed characteristic N3 in FIG. The eco-mode switching position 20c to be maintained is set.

  As shown in FIG. 4, the hydraulic excavator according to the present embodiment includes an engine 30 disposed in the engine compartment 12, an engine controller 36 that controls the rotation speed of the engine 30, and a variable displacement hydraulic pressure driven by the engine 30. A pump 31, a main relief valve 45 that regulates the maximum pressure of the pressure oil discharged from the variable displacement hydraulic pump 31, and a regulator 31 a that controls the displacement volume, that is, the tilt angle of the variable displacement hydraulic pump 31. Yes. Further, the hydraulic actuator 32 such as the boom cylinder 7, the arm cylinder 8, the bucket cylinder 9, the travel motor, and the swing motor that operates the working device 3, the swing body 2, or the travel body 1 and the like, and a variable capacity. And a control valve 34 for controlling the flow of pressure oil supplied from the hydraulic pump 31 to each of the hydraulic actuators 32. The operation devices 16 and 17 described above are shown as the operation device 37.

  In addition, the hydraulic excavator according to the present embodiment includes, for example, a pressure sensor 50 that serves as both an operation amount detection unit that detects the operation amount of the operation device 37 and an operation detection unit that detects the operation of the load body 33, and the main relief valve 45. An operation detection means for detecting the operation, that is, an operation detection sensor 51, and a stroke detection means for detecting that the hydraulic actuator 32 has reached the stroke end, that is, a stroke sensor 52 are provided.

  Further, the signals output from the engine control dial 19, the work mode switch 20, the pressure sensor 50, the operation detection sensor 51, and the stroke sensor 52 are input, and after performing predetermined processing, the corresponding signals are sent to the engine. A controller 36, a regulator 31 a, and a control device that outputs to the monitor 21, that is, a main controller 35 are provided.

  As shown in FIG. 4, the main controller 35 obtains the engine torque related to the work actually performed corresponding to the pump torque obtained based on the operation amount of the operation device 37 detected by the pressure sensor 50, for example. Based on the engine torque calculation unit 35a, the engine torque obtained by the engine torque calculation unit 35a, and the target engine speed output from the engine control dial 19, the load body 33 is driven and is actually implemented. A fuel efficiency determination unit 35b that determines whether the driving state related to the work is a driving state with good fuel efficiency;

  A region R with good fuel efficiency shown in FIG. 6 is set in the fuel efficiency determination unit 35b. This region R with good fuel efficiency is obtained empirically from the relationship between the engine target speed and the engine torque. In FIG. 6, NM is the reference target rotational speed when the work mode switch 20 is switched to the high power mode switching position 20a or the normal work mode switching position 20b, and NS is the reference mode rotational speed. A predetermined low rotational speed when switched to the position 20c is shown. In FIG. 6, reference numeral 40 denotes an engine horsepower diagram.

  For example, in a state where the work mode switch 20 is not switched to the eco mode switching position 20c, the working device 3 including the boom 4, the arm 5 and the bucket 6, that is, the load body 33 is driven, and the ground leveling work or the like is performed. When the light work is performed, the operation state related to the work that is actually performed exists in the light work area S1 that is not included in the fuel efficient area R from the relationship between the engine torque and the engine target speed. It may be judged as a state. That is, it may be determined that the driving state related to the work actually performed is not a driving state with good fuel efficiency. In such a case, when the work mode switch 20 is switched to the eco mode switching position 20c, the engine target speed is automatically lowered to the predetermined low speed NS shown in FIG. The driving state related to the shift to the light work area S2 included in the area R with good fuel efficiency. Accordingly, when such a state is reached, the fuel efficiency determination unit 35b determines that the driving state related to the work actually performed is a driving state with good fuel efficiency.

  Further, for example, when heavy excavation work such as debris is performed by driving the load body 33 including the work device 3 in a state where the work mode switch 20 is switched to the high power mode switching position 20a, It is determined that the operation state related to the work performed in the above is in the heavy excavation region S3 included in the region R with high fuel efficiency from the relationship between the engine torque and the engine target rotational speed. That is, the fuel efficiency determination unit 35b determines that the driving state related to the work actually performed is a driving state with high fuel efficiency. In FIG. 6, S3a indicates a relief area.

  Although not shown, the main controller 35 provided in the hydraulic excavator according to the present embodiment determines whether the operation of the load body 33 does not adversely affect the fuel efficiency based on, for example, the detection result of the pressure sensor 50, that is, the detection value. An operation determining unit for determining is included. Here, the operation that does not adversely affect the fuel efficiency includes, for example, a boom lowering operation in which the boom 4 is freely dropped or a deceleration operation of the revolving body 2 when the revolving body 2 is stopped.

  Although not shown, the main controller 35 includes a relief operation determination unit that determines whether the main relief valve 45 has operated based on the detection result of the operation detection sensor 51, and a hydraulic actuator based on the detection result of the stroke detection means. A stroke end determination unit for determining whether or not 32 has reached the stroke end is included.

  In addition, the hydraulic excavator according to the present embodiment is provided with a display unit capable of displaying information on fuel efficiency on the monitor 21, for example, a lamp display unit 21a. The main controller 35 described above performs a process of displaying the determination result in the fuel efficiency determination unit 35b on the lamp display unit 21a. In this case, for example, when it is determined by the determination in the fuel efficiency determination unit 35b that the driving state related to the work actually performed by driving the load body 33 is a driving state with high fuel efficiency, the main controller 35 When the process of turning on the lamp display unit 21a is performed and it is determined that the driving state is not fuel efficient, the main controller 35 performs the process of turning off the lamp display unit 21a.

  In addition, when the above-described operation determining unit (not shown) of the main controller 35 determines that the operation of the load body 33 is an operation that does not adversely affect the fuel efficiency, it can be regarded as a driving state with high fuel efficiency. In order to display on the display lamp 21a of the monitor 21, the main controller 35 performs a process of lighting the lamp display unit 21a.

  Further, when it is determined that the main relief valve 45 is operated by the above-described relief operation determining unit (not shown) of the main controller 35, and the hydraulic actuator 32 reaches the stroke end by the above-described stroke end determining unit (not shown) of the main controller 35. When it is determined, the main controller 35 performs a process of turning off the lamp display portion 21a in order to display on the display lamp 21a of the monitor 21 that it can be assumed that the driving state is not fuel efficient.

  In the hydraulic excavator according to the present embodiment configured as described above, the fuel efficiency determination unit 35b of the main controller 35 has the engine torque related to the actual work performed by the engine torque calculation unit 35a and the engine control dial 19. The driving state related to the work actually performed based on the target engine speed related to the work actually performed output from the operation state included in the region R with good fuel efficiency of FIG. Whether the driving state related to the work actually performed is high in fuel efficiency by checking whether the lamp display portion 21a of the monitor 21 is turned on or off. You can check at a glance whether it is bad.

  In this case, if the lamp display portion 21a of the monitor 21 is lit, the operator can confirm that the driving state related to the work actually performed is a driving state with good fuel efficiency, if the lighting state is observed. Further, if the lamp display unit 21a is turned off, the operator can confirm that the driving state related to the work actually performed is a driving state in which the fuel efficiency is not good, and the fuel efficiency can be improved. You are prompted to get better driving conditions. That is, in the present embodiment, the main controller 35 includes the engine torque calculation unit 35a and the fuel efficiency determination unit 35b, and the lamp display unit 21a that displays the determination result in the fuel efficiency determination unit 35b on the monitor 21. The operator determines whether the driving state related to the work actually performed including both elements of the driving state of the engine 30 and the operating state of the load body 33 including the working device 3 is a driving state with good fuel efficiency. The lamp display 21a can be seen immediately. Therefore, the operator can be strongly conscious of fuel consumption driving, which greatly contributes to the realization of energy saving.

  Further, in the present embodiment, the main controller 35 operates such that the operation of the load body 33 does not adversely affect the fuel efficiency, for example, the boom 4 and the arm 5 that are inertial bodies such as boom lowering, arm crowding, and turning deceleration. Including a motion determination unit (not shown) that determines whether the motion is in a direction to be lowered by the motion, or whether the motion is in a direction to decelerate the turning body 2 that is turning as an inertial body, such as during turning deceleration. When the determination unit determines that the operation of the load body 33 is an operation that does not adversely affect the fuel efficiency, the lamp display unit 21a is turned on to display that it can be regarded as a driving state with good fuel efficiency. Since the process is performed, the operator is not required to be aware of the fuel consumption driving in the work by the operation of the load body 33 that does not adversely affect the fuel efficiency. Can Unisuru. Further, when the fuel efficiency determination unit 35b of the main controller 35 determines that the work is being performed in the heavy excavation work area S3 of FIG. 6 with good fuel efficiency, a light load operation is temporarily entered. Even if it is determined that the vehicle is present in the light work area S1 with low fuel consumption, the operation determining unit of the main controller 35 performs an operation in which the operation of the load body 33 does not adversely affect the fuel efficiency as described above. When it is determined that the lamp display unit 21 is on, a process of continuously lighting the lamp display unit 21 is performed. Conversely, when the fuel efficiency determination unit 35b of the main controller 35 determines that the work is being performed in the light work area S1 with poor fuel consumption, the heavy excavation becomes temporarily heavy with high load due to high load. Even if it is determined that the work area S3 has been entered, if the work is a relief or stroke end, the lamp display unit 21 is kept off.

  In addition, the present embodiment includes a relief operation determination unit (not shown) that determines whether or not the main relief valve 45 has been operated. When the relief operation determination unit determines that the main relief valve 45 has been operated, that is, In order to display that it is possible to assume that the driving state related to the work actually performed is not included in the driving state with high fuel efficiency when it is determined that the driving state is included in the relief region S3a of FIG. The process of turning off the lamp display unit 21a is performed. Therefore, when the main relief valve 45 is operated, it is possible to ask the operator to be aware of fuel-efficient driving even if the operation has been performed in a fuel-efficient driving state. That is, the operator is prompted to perform an operation to return to the operation state in which the operation of the main relief valve 45 is stopped.

  In this embodiment, the main controller 35 determines whether the hydraulic actuator 32 has reached the stroke end in consideration of the case where the hydraulic actuator 32 may relieve when the hydraulic actuator 32 has reached the stroke end. In order to display that when the stroke end determination unit determines that the hydraulic actuator 32 has reached the stroke end, it can be assumed that the driving state is not fuel efficient by relief. In addition, the lamp display unit 21a is turned off. Therefore, when the hydraulic actuator 32 reaches the stroke end, it is possible to ask the operator to be aware of fuel consumption driving even if the operation has been performed in a fuel efficient operating state. That is, the operator is prompted to adjust the operation amount of the operation device 37 corresponding to the corresponding hydraulic actuator 32 as appropriate.

DESCRIPTION OF SYMBOLS 1 Traveling body 2 Revolving body 3 Working apparatus 4 Boom 5 Arm 6 Bucket 7 Boom cylinder (hydraulic actuator)
8 Arm cylinder (hydraulic actuator)
9 Bucket cylinder (hydraulic actuator)
10 cab 14 right travel lever 15 left travel lever 16 operating device 17 operating device 19 engine control dial (target rotational speed command means)
21 Monitor 21a Lamp display part (display part)
30 Engine 31 Variable displacement hydraulic pump 31a Regulator 32 Hydraulic actuator 33 Load body 35 Main controller (control device)
35a Engine torque calculation unit 35b Fuel efficiency determination unit 37 Operating device 40 Engine horsepower diagram 45 Main relief valve 50 Pressure sensor (operation amount detection means) (operation detection means)
51 Operation detection sensor (operation detection means)
52 Stroke sensor (stroke detection means)
S1 Light work area S2 Light work area S3 Heavy excavation work area S3a Relief area R Fuel efficient area

Claims (5)

An engine, target rotational speed command means for commanding the target rotational speed of the engine, a variable displacement hydraulic pump driven by the engine, and a main relief defining a maximum pressure of pressure oil discharged from the variable displacement hydraulic pump A display unit that includes a valve, a hydraulic actuator that is operated by pressure oil discharged from the variable displacement hydraulic pump, and a load body that includes a working device that is driven by the hydraulic actuator, and that can display information on fuel efficiency. In the provided hydraulic working machine,
Based on the engine torque calculation unit that calculates the engine torque related to the work that is actually performed, the engine torque calculated by the engine torque calculation unit, and the target engine speed output from the target engine speed command means, A fuel efficiency determination unit that determines whether or not the driving state related to the work actually performed by driving the load body is a driving state with high fuel efficiency, and the determination result in the fuel efficiency determination unit is A hydraulic working machine comprising a control device for performing processing to be displayed on the display unit. In the hydraulic working machine according to claim 1,
While equipped with an operation detection means for detecting the operation of the load body,
The control device includes an operation determination unit that determines whether the operation of the load body does not adversely affect fuel efficiency based on a detection result of the operation detection unit,
When the operation determining unit determines that the operation of the load body is an operation that does not adversely affect the fuel efficiency, the control device displays on the display unit that the operation state can be regarded as a fuel efficient operation state. The hydraulic working machine characterized by performing the process to make. In the hydraulic working machine according to claim 1,
With an operation detecting means for detecting the operation of the main relief valve,
The control device includes a relief operation determination unit that determines whether the main relief valve is operated based on a detection result of the operation detection means,
The control device performs a process of displaying on the display unit that it can be considered that the driving state is not fuel efficient when the relief operation determining unit determines that the main relief valve has been operated. A hydraulic working machine that features. In the hydraulic working machine according to claim 1,
Stroke detecting means for detecting that the hydraulic actuator has reached the stroke end, and
The control device includes a stroke end determination unit that determines whether the hydraulic actuator has reached a stroke end based on a detection result of the stroke detection unit,
When the stroke end determination unit determines that the hydraulic actuator has reached the stroke end, the control device performs processing to display on the display unit that it can be assumed that the driving state is not fuel efficient. A hydraulic working machine characterized by that. In the hydraulic working machine according to any one of claims 1 to 4,
A cab in which the target rotational speed command means is disposed and a monitor installed in the cab,
The hydraulic working machine according to claim 1, wherein the display unit includes a lamp display unit provided in the monitor.

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