CN114430786B - Engineering machinery - Google Patents

Abstract

The power reduction control can be performed when the operation lever is not operated, and the recovery to the normal power state when the operation lever is erroneously moved can be suppressed, and the operation can be smoothly shifted to the desired operation when the operation lever is recovered to the normal power state. Therefore, in the power reduction state, when the 1 st release condition for simultaneously releasing more than two operation levers or when the 2 nd release condition for continuously releasing one lever is met, the controller (50) judges that the operator has 'intention to release the power reduction', and releases the power reduction control.

Description

Engineering machinery

Technical Field

The present invention relates to a construction machine such as a hydraulic excavator, and more particularly to a construction machine that performs power reduction control for reducing power output from a power source when an operation lever is not operated.

Background

In a construction machine, for example, patent document 1 describes a technique of performing power reduction control called automatic idle control in which the rotation speed of an engine is reduced and the power output from the engine is reduced when an operation lever is not operated.

As an anti-theft device for construction machines, for example, patent documents 2 and 3 describe a technique for performing authentication based on an input mode of an operation lever.

Prior art literature

Patent literature

Patent document 1: WO2018/179313

Patent document 2: japanese patent laid-open No. 11-140918

Patent document 3: japanese patent laid-open No. 2018-016985

Disclosure of Invention

In a construction machine that performs power reduction control (automatic idle control) for reducing power output from an engine as a power source when an operation lever is not operated as described in patent document 1, the power reduction control is generally released and a normal power state can be restored when the operation lever is operated. However, when the power reduction control is performed in this way, there is a problem that the control is released although the power reduction control is not intended to be released, for example, when the operator touches the lever by hand.

As a solution to this problem, it is conceivable to apply an authentication technique for the input mode of the joystick as described in patent documents 2 and 3. By applying such authentication technique, the power-off control can be released and restored to the normal power state only in the case where the power-off control is intended.

However, in this method, there is a problem that smooth transition to a desired operation is not possible when the normal power state is restored. For example, when the set recognition mode is "forward right hand lever, forward left hand lever", and the desired operation is "backward right hand lever, and right hand lever", the operation lever needs to be returned to the neutral state after one operation in the set operation mode. The operator cannot smoothly shift to the desired action.

The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a construction machine that can perform power reduction control when an operation lever is not operated, can suppress restoration to a normal power state when the operation lever is erroneously moved, and can smoothly shift to a desired operation when the operation lever is restored to the normal power state.

In order to solve the above problem, a construction machine according to the present invention includes: a power source; a plurality of actuators that receive the power output from the power source and operate; a plurality of operation levers for indicating the distribution amount of the power to the plurality of actuators; a plurality of operation state detection devices for detecting operation states of the plurality of operation levers; and a controller for controlling the power source, wherein the plurality of operation levers have 1 st and 2 nd operation levers for operating different ones of the plurality of actuators, and wherein the controller performs power reduction control for reducing the power when a non-operation state of the 1 st and 2 nd operation levers is continued, and wherein the controller releases the power reduction control when a 1 st release condition is satisfied in which the 1 st and 2 nd operation levers are simultaneously operated in a state in which the power is reduced.

Effects of the invention

According to the present invention, the power reduction control can be performed when the 1 st and 2 nd operation levers are not operated, and the power reduction control can be released only by simultaneously operating the 1 st and 2 nd operation levers in the power reduction state. When one of the 1 st and 2 nd operation levers is erroneously operated, the return to the normal power state can be suppressed without canceling the power reduction control. Further, since the power reduction control is released only by simultaneously operating the 1 st and 2 nd operation levers in the power reduction state, the operation can be smoothly shifted to a desired operation when the normal power state is restored.

Drawings

Fig. 1 is a view showing an external appearance of a construction machine (hydraulic excavator) according to embodiment 1 of the present invention.

Fig. 2 is a diagram showing a configuration of a drive system in embodiment 1.

Fig. 3 is a diagram illustrating the movable direction and definition of the movable direction of the lever device in embodiment 1.

Fig. 4 is a diagram showing a configuration of an operation signal system of the drive system in embodiment 1.

Fig. 5 is a block diagram showing the function of the controller in embodiment 1.

Fig. 6 is a block diagram showing the function of the power calculation unit in embodiment 1.

Fig. 7 is a flowchart showing the operation flow of the 1 st lever operation state determination unit in embodiment 1.

Fig. 8 is a flowchart showing the operation flow of the 2 nd lever operation state determination unit in embodiment 1.

Fig. 9 is a diagram showing a relationship between a sensor value and an inlet throttle opening area of a directional control valve in embodiment 1, and showing definition of a threshold value of an operating pressure.

Fig. 10 is a flowchart showing the operation flow of the 1 st stick operation time measurement unit in embodiment 1.

Fig. 11 is a flowchart showing the operation flow of the 2 nd lever operation time measuring unit in embodiment 1.

Fig. 12 is a flowchart showing the operation flow of the power reduction determination unit in embodiment 1.

Fig. 13 is a time chart showing an example of transition between the operating pressure and the target rotational speed when the lever is operated in embodiment 1.

Fig. 14 is a block diagram showing the function of the power calculation unit of the controller according to the modification of embodiment 1.

Fig. 15 is a flowchart showing an operation flow of the power reduction determination unit in the modification of embodiment 1.

Fig. 16 is a diagram showing a configuration of a drive system according to embodiment 2.

Fig. 17 is a block diagram showing the function of the controller in embodiment 2.

Fig. 18 is a block diagram showing the function of the power calculation unit in embodiment 2.

Fig. 19 is a flowchart showing the operation flow of the power reduction determination unit in embodiment 2.

Fig. 20 is a diagram showing a modification of the drive system in embodiment 2.

Fig. 21 is a diagram showing a configuration of a drive system in embodiment 3.

Fig. 22 is a diagram showing the configuration of the operation signal system of the drive system in embodiment 3.

Fig. 23 is a diagram showing a relationship between the gradient of the lever in the front-rear direction and the target rotation speed of the electric motor in embodiment 3.

Fig. 24 is a block diagram showing the function of the controller in embodiment 3.

Fig. 25 is a diagram illustrating conversion processing performed by the sensor signal conversion unit in embodiment 3.

Fig. 26 is a block diagram showing the function of the power calculation unit in embodiment 3.

Fig. 27 is a flowchart showing the operation flow of the 1 st lever operation state determination unit in embodiment 3.

Fig. 28 is a flowchart showing the operation flow of the 2 nd lever operation state determination unit in embodiment 3.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Embodiment 1

Embodiment 1 of the present invention will be described with reference to fig. 1 to 13.

-structure to

First, a hydraulic excavator according to embodiment 1 of the present invention, which is a typical example of a construction machine, will be described.

Fig. 1 is a view showing an external appearance of a hydraulic excavator according to the present embodiment.

The hydraulic excavator includes a lower traveling structure 101, an upper swing structure 102 rotatably mounted on the lower traveling structure, and a swing front work implement 104 rotatably mounted in the up-down direction on the front portion of the upper swing structure, and the front work implement 104 includes a boom 111, an arm 112, and a bucket 113. The upper rotation 102 and the lower running body 101 are rotatably connected by a rotation ring 215, and the upper rotation body 102 is rotatable relative to the lower running body 101 by rotation of the rotation motor 43. A swing tower 103 is attached to the front part of the upper swing body 102, and a front working machine 104 is attached to the swing tower 103 so as to be movable up and down. The swing tower 103 is rotatable in a horizontal direction with respect to the upper swing body 102 by extension and contraction of a swing cylinder (not shown), and the boom 111, the arm 112, and the bucket 113 of the front work implement 104 are rotatable in a vertical direction by extension and contraction of the boom cylinder 13, the arm cylinder 23, and the bucket cylinder 33, which are front actuators. Right and left traveling devices 105a and 105b and a blade 106 that moves up and down by extension and contraction of blade cylinder 3h are attached to the center frame of lower traveling body 101. The right and left traveling devices 105a and 105b include driving wheels 210a and 210b, idler wheels 211a and 211b, and crawler belts 212a and 212b, respectively, and travel is performed by transmitting rotation of the right and left traveling motors 3f and 3g to the driving wheels 210a and 210b to drive the crawler belts 212a and 212 b.

An operation room 110 forming a cab 108 is provided in the upper swing body 102, and a driver's seat 122 and right and left lever devices 114, 134 for instructing driving of the boom cylinder 13, the arm cylinder 23, the bucket cylinder 33, and the swing motor 43 are provided in the cab 108.

Next, a drive system mounted on a construction machine (hydraulic excavator) according to the present embodiment will be described. Fig. 2 is a diagram showing a configuration of a drive system according to the present embodiment.

In fig. 2, the drive system includes a hydraulic pump 1 and a pilot pump 51 of an engine 6 (diesel engine) and a main pump, and the hydraulic pump 1 and the pilot pump 51 are driven by the engine 6. The hydraulic pump 1 is connected to a line 2, and a relief valve 3 is attached to the line 2 via a relief line 4. The downstream side of the relief valve 3 is connected to a tank 5. Downstream of the line 2, a series line 8 and a parallel line 9 are connected. The parallel line 9 is connected in parallel with lines 11, 21, 31, 41. The check valves 10, 20, 30, 40 are disposed in the pipes 11, 21, 31, 41, respectively.

A directional control valve 12 is connected downstream of the line 8 and the line 11, and the directional control valve 12 is connected to a cylinder bottom line 13B connected to a cylinder bottom side chamber of the boom cylinder 13, a piston rod line 13R connected to a piston rod side chamber of the boom cylinder 13, a tank line 13T connected to the tank 5, and an intermediate bypass line 13C.

The directional control valve 12 is driven by the pressure of the pilot conduit 12b and the pressure of the pilot conduit 12 r. When the pressures of both pilot lines are low, the directional control valve 12 is in the neutral position, the line 8 is connected to the intermediate bypass line 13C, and the other lines are shut off. When the pressure in the pilot line 12b is high, the directional control valve 12 is switched to the upper side of the figure, the line 11 is connected to the cylinder bottom line 13, the tank line 13T is connected to the piston rod line 13R, and the line 8 and the intermediate bypass line 13C are shut off. When the pressure in the pilot line 12R is high, the directional control valve 12 is switched to the lower side of the drawing, the line 11 is connected to the piston rod line 13R, the tank line 13T is connected to the bottom line 13B, and the line 8 and the intermediate bypass line 13C are shut off.

Downstream of the lines 13C and 21, a directional control valve 22 is connected. The directional control valve 22 is also connected to a bottom pipe 23B connected to a bottom side chamber of the arm cylinder 23, a rod pipe 23R connected to a rod side chamber of the arm cylinder 23, a tank pipe 23T connected to the tank 5, and a middle bypass pipe 23C.

The directional control valve 22 is driven by the pressure of the pilot conduit 22b and the pressure of the pilot conduit 22 r. When the pressures of both pilot lines are low, the directional control valve 22 is in the neutral position, the intermediate bypass line 13C is connected to the intermediate bypass line 23C, and the other lines are shut off. When the pressure in the pilot line 22B is high, the directional control valve 22 is switched to the upper side of the figure, the line 21 is connected to the bottom line 23B, the tank line 23T is connected to the rod line 23R, and the intermediate bypass line 13C and the intermediate bypass line 23C are shut off. When the pressure in the pilot line 22R is high, the directional control valve 22 is switched to the lower side of the drawing, the line 21 is connected to the piston rod line 23R, the tank line 23T is connected to the bottom line 23B, and the intermediate bypass line 13C and the intermediate bypass line 23C are shut off.

Downstream of the line 23C and the line 31, a direction control valve 32 is connected, and the direction control valve 32 is further connected to a cylinder bottom line 33B connected to a cylinder bottom side chamber of the bucket cylinder 33, a piston rod line 33R connected to a piston rod side chamber of the bucket cylinder 33, a tank line 33T connected to the tank 5, and an intermediate bypass line 33C.

Directional control valve 32 is driven by the pressure of pilot conduit 32b and the pressure of pilot conduit 32 r. When the pressures of both pilot lines are low, the directional control valve 32 is in the neutral position, the intermediate bypass line 23C is connected to the intermediate bypass line 33C, and the other lines are shut off. When the pressure in the pilot line 32B is high, the directional control valve 32 is switched to the upper side of the figure, the line 31 is connected to the bottom line 33B, the tank line 33T is connected to the rod line 33R, and the intermediate bypass line 23C and the intermediate bypass line 33C are shut off. When the pressure in the pilot line 32R is high, the directional control valve 32 is switched to the lower side of the drawing, the line 31 is connected to the piston rod line 33R, the tank line 33T is connected to the bottom line 33B, and the intermediate bypass line 23C and the intermediate bypass line 33C are shut off.

Downstream of the line 33C and the line 41, a direction control valve 42 is connected, and the direction control valve 42 is also connected to a left rotation line 43L connected to a left rotation side chamber of the rotation motor 43, a right rotation line 43R connected to a right rotation side chamber of the rotation motor 43, a tank line 43T connected to the tank 5, and an intermediate bypass line 43C. The intermediate bypass line 43C is connected to the tank 5.

Directional control valve 42 is driven by the pressure of pilot conduit 42l and the pressure of pilot conduit 42 r. When the pressures of both pilot lines are low, the directional control valve 42 is in the neutral position, the intermediate bypass line 33C is connected to the intermediate bypass line 43C, and the other lines are shut off. When the pressure in the pilot line 42L is high, the directional control valve 42 is switched to the upper side of the drawing, the line 41 is connected to the left rotation line 43L, the tank line 43T is connected to the right rotation line 43R, and the intermediate bypass line 33C and the intermediate bypass line 43C are shut off. When the pressure in the pilot line 42R is high, the directional control valve 42 is switched to the lower side of the drawing, the line 41 is connected to the right rotation line 43R, the tank line 43T is connected to the left rotation line 43L, and the intermediate bypass line 33C and the intermediate bypass line 43C are shut off.

The pilot pump 51 is connected to a pilot line 52. As to the downstream from pilot conduit 52, the following description will be made with reference to fig. 4.

Although not shown, the hydraulic drive system is provided with directional control valves similar to those of the travel motors 3f and 3g, the blade cylinder 3h, and the swing cylinder not shown in fig. 1, and the pipes are connected and disconnected.

Here, the engine 6 and the hydraulic pump 1 constitute a power source, and the boom cylinder 13, the arm cylinder 23, the bucket cylinder 33, and the swing motor 43 constitute a plurality of actuators that operate by receiving power output from the power source. The lever devices 114 and 134 each have right and left levers 14 and 34 (1 st and 2 nd levers) that indicate the amount of power allocated to the plurality of actuators, and the directional control valves 12, 22, 32 and 42 allocate power to the plurality of actuators based on the instruction of the levers 14 and 34.

Next, the configuration of the operation signal system of the drive system will be described with reference to fig. 3 and 4.

Fig. 3 is a diagram illustrating the movable direction and definition of the movable direction of the operation lever devices 114 and 134 in embodiment 1.

As described with reference to fig. 1, the right and left lever devices 114 and 134 are provided in the cab 108 of the hydraulic excavator, and the operator operates the lever 14 (1 st lever) of the lever device 114 with the right hand and operates the lever 34 (2 nd lever) of the lever device 134 with the left hand. The lever devices 114, 134 are each capable of actuating two actuators via one lever 14 or 34. The operation levers 14 and 34 are operable from the neutral positions, respectively, the operation of the front direction 14b and the rear direction 14r of the operation lever 14 corresponds to the boom lowering and raising operations of the boom cylinder 13, the operation of the right direction 24r and the left direction 24b of the operation lever 14 corresponds to the bucket unloading and bucket loading operations of the bucket cylinder 33, the operation of the right direction 34b and the left direction 34r of the operation lever 34 corresponds to the arm retracting and arm releasing operations of the arm cylinder 23, and the operation of the front direction 44l and the rear direction 44r of the operation lever 34 corresponds to the right rotation and left rotation operations of the rotation motor 43. In the present specification, the front direction, the rear direction, the right direction, and the left direction refer to the front direction, the rear direction, the right direction, and the left direction of the upper rotating body 102 as the vehicle body.

The levers 14 and 34 of the lever devices 114 and 134 can be operated in a plurality of directions from the neutral position, and different actuators among the plurality of actuators (the boom cylinder 13, the arm cylinder 23, the bucket cylinder 33, and the swing motor 43) can be operated.

Fig. 4 is a diagram showing a configuration of an operation signal system of the drive system.

In fig. 4, the lever devices 114 and 134 are of a hydraulic pilot type, the lever device 114 has boom pilot valves 15b and 15r and bucket pilot valves 25b and 25r driven by the lever 14, and the lever device 134 has arm pilot valves 35b and 35r and rotary pilot valves 45l and 45r driven by the lever 34. In the following description, the operation lever is sometimes simply referred to as a "lever".

Downstream of the pilot line 52, lines 19, 29, 39, 49 and a relief valve 53 are connected in parallel. A tank 5 is connected downstream of the relief valve 53. The pipes 19, 29, 39, 49 are provided with throttle portions 94, 95, 96, 97, respectively.

The pilot valve 15b of the lever apparatus 114 is connected to the line 19, and is connected to the lines 18 and 16 b. Conduit 16b is connected to pilot conduit 12b (see fig. 2). A pressure sensor 17b is mounted on the pipe 16 b. The line 18 is connected to the tank 5.

When the lever 14 is in the neutral position, the pilot valve 15b connects the line 18 to the line 16b, and cuts off the line 19. When the lever 14 is operated in the forward direction 14b, the pilot valve 15b connects the line 19 with the line 16b, cutting off the line 18. At this time, a pressure (operation pressure) corresponding to the operation amount of the lever 14 is generated in the pipe 16 b.

The pressure sensor 17b measures the pressure of the line 16b and sends a signal to the electrically connected controller 50.

The pilot valve 15r of the lever apparatus 114 is connected to the line 19, and is connected to the lines 18 and 16 r. Conduit 16r is connected to pilot conduit 12r (see fig. 2). A pressure sensor 17r is mounted on the pipe 16 r. The line 18 is connected to the tank 5.

When the lever 14 is in the neutral position, the pilot valve 15r connects the line 18 to the line 16r, and cuts off the line 19. When the lever 14 is operated in the backward direction 14r, the pilot valve 15r connects the pipe 19 to the pipe 16r, and cuts off the pipe 18. At this time, a pressure corresponding to the operation amount of the lever 14 is generated in the pipe 16 r.

The pressure sensor 17r measures the pressure of the line 16r and sends a signal thereof to the electrically connected controller 50.

The pilot valve 25b of the lever apparatus 114 is connected to the pipe 29, and to the pipes 28 and 26 b. Conduit 26 is connected to pilot conduit 32b (see fig. 2). A pressure sensor 27b is mounted on the pipe 26 b. The line 28 is connected to the tank 5.

When the lever 14 is in the neutral position, the pilot valve 25b connects the line 28 to the line 26b, and cuts off the line 29. When the lever 14 is operated in the left direction 24b, the pilot valve 25b connects the pipe 29 to the pipe 26b, and cuts off the pipe 28. At this time, a pressure (operation pressure) corresponding to the operation amount of the lever 14 is generated in the pipe 26 b.

The pressure sensor 27b measures the pressure in the line 26b and sends a signal to the electrically connected controller 50.

The pilot valve 25r of the lever apparatus 114 is connected to the line 29, and is connected to the lines 28 and 26 r. Conduit 26r is connected to pilot conduit 32r (see fig. 2). A pressure sensor 27r is mounted on the pipe 26 r. The line 28 is connected to the tank 5.

When the lever 14 is in the neutral position, the pilot valve 25r connects the line 28 to the line 26r, and cuts off the line 29. When the lever 14 is operated in the rightward direction 24r, the pilot valve 25r connects the line 29 to the line 26r, and cuts off the line 28. At this time, a pressure (operation pressure) corresponding to the operation amount of the lever 14 is generated in the pipe 26 r.

The pressure sensor 27r measures the pressure in the line 26r and sends a signal to the electrically connected controller 50.

The pilot valve 35b of the lever apparatus 134 is connected to the line 39, and is connected to the line 38 and the line 36 b. Conduit 36b is connected to pilot conduit 22b (see fig. 2). A pressure sensor 37b is mounted on the pipe 36 b. The line 38 is connected to the tank 5.

When the lever 34 is in the neutral position, the pilot valve 35b connects the line 38 to the line 36b, and cuts off the line 39. When the lever 34 is operated in the rightward direction 34b, the pilot valve 35 connects the line 39 to the line 36b, and cuts off the line 38. At this time, a pressure (operation pressure) corresponding to the operation amount of the lever 34 is generated in the pipe 36 b.

The pressure sensor 37b measures the pressure in the line 36b and sends a signal to the electrically connected controller 50.

The pilot valve 35 of the lever apparatus 134 is connected to the line 39, and is connected to the line 38 and the line 36 r. Conduit 36r is connected to pilot conduit 22r (see fig. 2). A pressure sensor 37r is mounted on the pipe 36 r. The line 38 is connected to the tank 5.

When the lever 34 is in the neutral position, the pilot valve 35r connects the line 38 to the line 36r, and cuts off the line 39. When the lever 34 is operated in the left direction 34r, the pilot valve 35r connects the line 39 to the line 36r, and cuts off the line 38. At this time, a pressure (operation pressure) corresponding to the operation amount of the lever 34 is generated in the pipe 36 r.

The pressure sensor 37r measures the pressure in the line 36r and sends a signal to the electrically connected controller 50.

The pilot valve 45l of the lever apparatus 134 is connected to the line 49, and is connected to the line 48 and the line 46 l. Conduit 46l is connected to pilot conduit 42l (see fig. 2). A pressure sensor 47l is mounted on the line 46 l. The line 48 is connected to the tank 5.

When the lever 34 is in the neutral position, the pilot valve 45l connects the line 48 to the line 46l, and cuts off the line 49. When lever 34 is operated in forward direction 44l, pilot valve 45l connects line 49 with line 46l, cutting off line 48. At this time, a pressure (operating pressure) corresponding to the operation amount of the lever 34 is generated in the pipe 46 l.

The pressure sensor 47l measures the pressure of the line 46l and sends a signal to the electrically connected controller 50.

The pilot valve 45r of the lever apparatus 134 is connected to the line 49, and is connected to the line 48 and the line 46 r. Conduit 46r is connected to pilot conduit 42r (see fig. 2). A pressure sensor 47r is mounted on the pipe 46 r. The line 48 is connected to the tank 5.

When the lever 34 is in the neutral position, the pilot valve 45r connects the line 48 to the line 46r, and cuts off the line 49. When the lever 34 is operated in the backward direction 44r, the pilot valve 45r connects the line 49 with the line 46r, and cuts off the line 48. At this time, a pressure (operating pressure) corresponding to the operation amount of the lever 34 is generated in the pipe 46 r.

The pressure sensor 47r measures the pressure in the line 46r and sends a signal to the electrically connected controller 50.

The pressure sensors 17b, 17r, 27b, 27r, 37b, 37r, 47l, 47r constitute a plurality of operation state detection means for detecting the operation states of the lever means 114, 134. The pressure sensors 17b and 17r constitute 1 st operation state detection means for detecting the operation state of the operation lever 14 in the front-rear direction, the pressure sensors 27b and 27r constitute 2 nd operation state detection means for detecting the operation state of the operation lever 14 in the right-left direction, the pressure sensors 37b and 37r constitute 3 rd operation state detection means for detecting the operation state of the operation lever 34 in the right-left direction, and the pressure sensors 47l and 47r constitute 4 th operation state detection means for detecting the operation state of the operation lever 34 in the front-rear direction.

The operation signal system is provided with a lever device similar to that of the travel motors 3f and 3g, the blade cylinder 3h, and the swing cylinder not shown in fig. 1, though not shown. In the present embodiment, an operation state detection device may be provided for these lever devices, and power reduction control described later may be performed based on the operation state.

Returning to fig. 2, the drive system of the present embodiment further includes a controller 50 and a switch 76.

The controller 50 is electrically connected to the pressure sensors 17b, 17r, 27b, 27r, 37b, 37r, 47l, 47r, the switch 76, and the target rotation speed indicator 77. The controller 50 receives the signals of the measured pressures from the pressure sensors 17b to 47r, the signal from the switch 76, and the signal from the target rotation speed instruction device 77, calculates the target rotation speed of the engine 6 based on these signals, and transmits a command signal as a command value of power to the rotation speed control device 7 of the engine 6 electrically connected to the controller 50. The rotation speed control device 7 controls the engine 6 so as to be the target rotation speed.

The switch 76 is a switch that switches whether or not to set the power reduction control mode by sending an ON or OFF signal to the controller 50, and when the signal of the switch 76 is OFF, the power reduction control mode is released, and the driving power of the engine 6 is not reduced even if all the operation levers are in the non-operation state.

Next, the function of the controller 50 in embodiment 1 will be described. Fig. 5 is a block diagram showing the function of the controller 50.

In fig. 5, the controller 50 has functions of a sensor signal conversion unit 50a, a constant/table storage unit 50b, and a power calculation unit 50c.

The sensor signal conversion unit 50a receives signals transmitted from the pressure sensors 17b to 47r and the switch 76, and converts the signals into pressure information and switch flag information. The sensor signal conversion unit 50a transmits the converted pressure information and the switch flag information to the power calculation unit 50c. The pressure information converted by the sensor signal converting unit 50a is represented as sensor values P17b (t), P17r (t), P27b (t), P27r (t), P37b (t), P37r (t), P47l (t), and P47r (t), and the switching information converted by the sensor signal converting unit 50a is represented as a switching flag Fsw (t). The pressure information converted by the sensor signal conversion unit 50a is the pressure generated in the lines 16b to 46r by driving the pilot valves 15b to 45r, and the sensor values P17b (t), P17r (t), P27b (t), P27r (t), P37b (t), P37r (t), P47l (t), and P47r (t) are sometimes referred to as "operating pressures". Note that Fsw (t) =true (active) when the switch 76 is ON, and Fsw (t) =false (inactive) when it is OFF.

The constant/table storage unit 50b stores the constants and tables necessary for calculation in advance, and sends these pieces of information to the power calculation unit 50c.

The power calculation unit 50c receives the pressure information and the switch flag information sent from the sensor signal conversion unit 50a, the target rotation speed information sent from the target rotation speed instruction device 77, and the constant information and the table information sent from the constant/table storage unit 50b, and calculates the target rotation speed of the engine 6. Then, the power computing unit 50c outputs the target rotation speed to the rotation speed control device 7.

Next, the function of the power calculation unit 50c in embodiment 1 will be described. Fig. 6 is a block diagram showing the function of the power calculation unit 50c. Further, the sampling time of the controller 50 is Δt.

In fig. 6, the power computing unit 50c has the functions of the 1 st lever operation state determining unit 50c-1, the 2 nd lever operation state determining unit 50c-2, the 1 st lever operation time measuring unit 50c-3, the 2 nd lever operation time measuring unit 50c-4, the power reduction determining unit 50c-5, and the delay element 50 c-6.

The 1 st lever operation state determination unit 50c-1 determines whether the lever 14 is being operated based on the sensor values P17b (t), P17r (t), P27b (t), and P27r (t), and outputs a 1 st lever no-operation flag F14 (t). The 1 st lever operation state determination unit 50c-1 sets the 1 st lever no-operation flag F14 (t) to true if it is determined that the lever 14 is not operated, and sets the 1 st lever no-operation flag F14 (t) to false if it is determined that the lever 14 is being operated. The flag information is sent to the 1 st lever operation time measuring section 50c-3 and the power reduction judging section 50c-5.

The 2 nd lever operation state determination unit 50c-2 determines whether the lever 34 is being operated based on the sensor values P37b (t), P37r (t), P47l (t), P47r (t), and outputs a 2 nd lever no-operation flag F34 (t). The 2 nd lever operation state determination unit 50c-2 sets the 2 nd lever no-operation flag F34 (t) to true if it is determined that the lever 34 is not operated, and sets the 2 nd lever no-operation flag F34 (t) to false if it is determined that the lever 34 is being operated. The flag information is sent to the 2 nd lever operation time measuring section 50c-4 and the power reduction judging section 50c-5.

The 1 st lever operation time measuring unit 50c-3 measures the 1 st lever no-operation time Tu14 (t) and the 1 st lever operation time Tc14 (t). These pieces of time information are sent to the power reduction judgment section 50c-5.

The 2 nd lever operation time measuring unit 50c-4 measures the 2 nd lever non-operation time Tu34 (t) and the 2 nd lever operation time Tc34 (t). These pieces of time information are sent to the power reduction judgment section 50c-5.

The power reduction determination unit 50c-5 determines whether or not to reduce the target rotation speed based on the flag information F14 (t), F34 (t), time information Tu14 (t), tc14 (t), tu34 (t), tc34 (t), the power reduction flag F50 (t- Δt) and the switch flag Fsw (t) before step 1 generated by the delay element 50c-6, and outputs the target rotation speed and the power reduction flag F50 (t) based on the determination result and the target rotation speed of the target rotation speed instruction device 77. The power reduction determination unit 50c-5 sets the power reduction flag F50 (t) to true when it determines that the target rotation speed is reduced, and sets the power reduction flag F50 (t) to false when it determines that the target rotation speed is not reduced.

Next, the function of the 1 st lever operation state determination unit 50c-1 in embodiment 1 will be described. Fig. 7 is a flowchart showing the operation flow of the 1 st lever operation state determination unit 50c-1 in fig. 6. This operation flow is repeatedly processed at the sampling time Δt during the operation of the controller 50, for example.

In step S101, the operation of the 1 st lever operation state determining unit 50c-1 is started.

In step S102, the 1 st lever operation state determination unit 50c-1 determines whether the sensor value P17b (t) is equal to or smaller than the threshold value Pth. If the sensor value P17b (t) is equal to or less than the threshold value Pth, the process proceeds to step S103. If the sensor value P17b (t) is greater than the threshold value Pth, the determination is no, and the process proceeds to step S107.

In step S103, the 1 st lever operation state determination unit 50c-1 determines whether the sensor value P17r (t) is equal to or smaller than the threshold value Pth. If the sensor value P17r (t) is equal to or less than the threshold value Pth, the process proceeds to step S104. If the sensor value P17r (t) is greater than the threshold value Pth, the determination is no, and the process proceeds to step S107.

In step S104, the 1 st lever operation state determination unit 50c-1 determines whether the sensor value P27b (t) is equal to or smaller than the threshold value Pth. If the sensor value P27b (t) is equal to or less than the threshold value Pth, the process proceeds to step S105. If the sensor value P27b (t) is greater than the threshold value Pth, the determination is no, and the process proceeds to step S107.

In step S105, the 1 st lever operation state determination unit 50c-1 determines whether the sensor value P27r (t) is equal to or smaller than the threshold value Pth. If the sensor value P27r (t) is equal to or smaller than the threshold value Pth, the process proceeds to step S106. If the sensor value P27r (t) is greater than the threshold value Pth, the determination is no, and the process proceeds to step S107.

In step S106, the 1 st lever operation state determination portion 50c-1 determines that the lever 14 is not operated and sets the 1 st lever no-operation flag F14 (t) to true. Then, the flag information is sent to the 1 st lever operation time measuring section 50c-3 and the power reduction judging section 50 c-5.

In step S107, the 1 st lever operation state determination section 50c-1 determines that the lever 14 is being operated and sets the 1 st lever no-operation flag F14 (t) to false. Then, the flag information is sent to the 1 st lever operation time measuring section 50c-3 and the power reduction judging section 50 c-5.

Next, the function of the 2 nd lever operation state determining section 50c-2 in embodiment 1 will be described. Fig. 8 is a flowchart showing the operation flow of the 2 nd lever operation state judgment part 50c-2 in fig. 6. This operation flow is repeatedly processed at the sampling time Δt during the operation of the controller 50, for example.

In step S201, the operation of the 2 nd lever operation state determining unit 50c-2 is started.

In step S202, the 2 nd lever operation state determination unit 50c-2 determines whether the sensor value P37b (t) is equal to or smaller than the threshold value Pth. If the sensor value P37b (t) is equal to or less than the threshold value Pth, the process proceeds to step S203. If the sensor value P37b (t) is greater than the threshold value Pth, the determination is no, and the process proceeds to step S207.

In step S203, the 2 nd lever operation state determination unit 50c-2 determines whether the sensor value P37r (t) is equal to or smaller than the threshold value Pth. If the sensor value P37r (t) is equal to or smaller than the threshold value Pth, the determination is yes, and the process proceeds to step S204. If the sensor value P37r (t) is greater than the threshold value Pth, the determination is no, and the process proceeds to step S207.

In step S204, the 2 nd lever operation state determination unit 50c-2 determines whether the sensor value P47l (t) is equal to or smaller than the threshold value Pth. If the sensor value P47l (t) is equal to or less than the threshold value Pth, it is determined that the determination is yes, and the process proceeds to step S205. If the sensor value P47l (t) is greater than the threshold value Pth, it is determined as no, and the process proceeds to step S207.

In step S205, the 2 nd lever operation state determination unit 50c-2 determines whether the sensor value P47r (t) is equal to or smaller than the threshold value Pth. If the sensor value P47r (t) is equal to or smaller than the threshold value Pth, the determination is yes, and the process proceeds to step S206. If the sensor value P47r (t) is greater than the threshold value Pth, the determination is no, and the process proceeds to step S207.

In step S206, the 2 nd lever operation state determination portion 50c-2 determines that the lever 34 is not operated and sets the 2 nd lever no-operation flag F34 (t) to true. Then, the flag information is sent to the 2 nd lever operation time measuring section 50c-4 and the power reduction judging section 50 c-5.

In step S207, the 2 nd lever operation state determination portion 50c-2 determines that the lever 14 is being operated and sets the 2 nd lever no-operation flag F34 (t) to false. Then, the flag information is sent to the 2 nd lever operation time measuring section 50c-4 and the power reduction judging section 50 c-5.

The definition of the threshold value Pth of the sensor value described above will be described with reference to fig. 9. Fig. 9 shows the relationship between the sensor value P17b (t) or P17r (t) and the meter-in opening area of the directional control valve 12. In addition, the sensor value P17b (t) or P17r (t) is expressed as "operation pressure".

In fig. 9, since the meter-in opening is not opened until the operating pressure P17b (t) or P17r (t) becomes the value of Pth, the hydraulic cylinder (boom cylinder) 13 does not operate. The relationship is also the same for other directional control valves. The operation state determination portions 50c-1, 50c-2 use the pressure value Pth at which the meter-in opening is open as a threshold value.

Next, the function of the 1 st lever operation time measuring unit 50c-3 in embodiment 1 will be described. Fig. 10 is a flowchart showing the operation flow of the 1 st lever operation time measuring unit 50c-3 shown in fig. 6. This operation flow is repeatedly processed at the sampling time Δt during the operation of the controller 50, for example.

In step S301, the operation of the 1 st lever operation time measuring unit 50c-3 is started.

In step S302, the 1 st lever operation time measuring unit 50c determines whether or not the 1 st lever no-operation flag F14 (t) is true. If the 1 st lever no operation flag F14 (t) is true, it is determined that it is yes, and the process proceeds to step S303. If the 1 st lever no operation flag F14 (t) is false, the process proceeds to step S304.

In step S303, since the lever 14 is not operated, the 1 st lever operation time measuring unit 50c sets a value obtained by adding the sampling time Δt to the 1 st lever no-operation time Tu14 (t- Δt) before the 1 st step as a new 1 st lever no-operation time Tu14 (t). Further, the 1 st lever operation time Tc14 (t) is set to 0. Then, these pieces of information are sent to the power reduction judgment section 50 c-5.

In step S304, since the lever 14 is being operated, the 1 st lever operation time measuring section 50c-3 sets the 1 st lever no-operation time Tu14 (t) to 0. The value obtained by adding the sampling time Δt to the 1 st lever operation time Tc14 (t- Δt) before the 1 st step is set as a new 1 st lever operation time Tc14 (t). Then, these pieces of information are sent to the power reduction judgment section 50 c-5.

Next, the function of the 2 nd lever operation time measuring unit 50c-4 in embodiment 1 will be described. Fig. 11 is a flowchart showing the operation flow of the lever 2 operation time measuring unit 50c-4 shown in fig. 6. This operation flow is repeatedly processed at the sampling time Δt during the operation of the controller 50, for example.

In step S401, the operation of the 2 nd lever operation time measuring unit 50c-4 is started.

In step S402, the 2 nd lever operation time measuring unit 50c-4 determines whether the 2 nd lever no-operation flag F34 (t) is true. If the 2 nd lever no-operation flag F34 (t) is true, it is determined that it is true, and the process proceeds to step S403. If the 2 nd lever no-operation flag F34 (t) is false, the process proceeds to step S404.

In step S403, since the lever 34 is not operated, the 2 nd lever operation time measuring unit 50c-4 sets a value obtained by adding the sampling time Δt to the 2 nd lever no-operation time Tu34 (t- Δt) before the 1 st step as a new 2 nd lever no-operation time Tu34 (t). Further, the 2 nd lever operation time Tc34 (t) is set to 0. Then, these pieces of information are sent to the power reduction judgment section 50 c-5.

In step S404, since the lever 34 is being operated, the 2 nd lever operation time measuring section 50c-4 sets the 2 nd lever non-operation time Tu34 (t) to 0. The value obtained by adding the sampling time Δt to the 2 nd lever operation time Tc34 (t- Δt) before the 1 st step is set as a new 2 nd lever operation time Tc34 (t). Then, these pieces of information are sent to the power reduction judgment section 50 c-5.

Next, the function of the power reduction determination unit 50c-5 in embodiment 1 will be described. Fig. 12 is a flowchart showing the operation flow of the power reduction determination unit 50c-5 shown in fig. 6. This operation flow is repeatedly processed at the sampling time Δt during the operation of the controller 50, for example.

In step S501, the operation of the power reduction determination unit 50c-5 is started.

In step S502, the power reduction determination unit 50c-5 determines whether or not the switch flag Fsw (t) is true. If the switch flag Fsw (t) is true, the process advances to step S503. If the switch flag Fsw (t) is false, the process advances to step S515.

In step S503, the power reduction determination unit 50c-5 determines whether or not the smaller one of the 1 st lever no-operation time Tu14 (t) and the 2 nd lever no-operation time Tu34 (t) is equal to or longer than a 1 st predetermined time Tth1 set in advance as a time to start the power reduction control. If the smaller one of the 1 st rod no-operation time Tu14 (t) and the 2 nd rod no-operation time Tu34 (t) is equal to or greater than the 1 st predetermined time Tth1, the process advances to step S510. If the smaller one of the 1 st lever no-operation time Tu14 (t) and the 2 nd lever no-operation time Tu34 (t) is smaller than the 1 st predetermined time Tth1, the process advances to step S504. The 1 st predetermined time Tth1 is, for example, 10 to 15 seconds. Thus, when neither lever 14 nor 34 is operated and the no-operation time Tu14 (t) or Tu34 (t) is equal to or longer than the 1 st predetermined time Tth1, the determination is yes, and the power reduction control (described later) is performed in step S510. If at least one of the levers 14 and 34 is operated and the lever being operated is returned to the neutral position without the power reduction control, the no-operation time Tu14 (t) and/or Tu34 (t) becomes 0, and the process proceeds to step S504 if the determination is negative. When at least one of the levers 14 and 34 is operated in the state of the power reduction control, the no-operation time Tu14 (t) and/or Tu34 (t) becomes 0, and therefore, the determination is no, and the process proceeds to step S504.

In step S504, the power-reduction determination unit 50c-5 determines whether or not the power-reduction flag F50 (t- Δt) before step 1 is true. If the power-down flag F50 (t- Δt) is true (if it was in the power-down control up to now), it is determined that it is yes, and the process proceeds to step S505. If the power reduction flag F50 (t- Δt) is false (if the power reduction control has been released up to now), it is determined as no, and the process proceeds to step S515, and the release of the power reduction control is continued (described later).

In step S505, the power reduction determination unit 50c-5 determines whether the 1 st lever no-operation flag F14 (t) is true. If the 1 st lever no-operation flag F14 (t) is true (if the lever 14 is not operated), the process advances to step S506. If the 1 st lever no-operation flag F14 (t) is false (if the lever 14 is operated), the process proceeds to step S508.

In step S506, the power reduction determination portion 50c-5 determines whether the 2 nd lever no-operation flag F34 (t) is true. If the 2 nd lever no-operation flag F34 (t) is true (if the lever 34 is not operated), the process proceeds to step S510, and the power reduction control (described later) is performed. If the 2 nd lever no-operation flag F34 (t) is false (if the lever 34 is being operated), it is determined as no, and the process proceeds to step S507.

In step S507, the power reduction determination unit 50c-5 determines whether or not the 2 nd lever operation time Tc34 (t) is longer than the 2 nd predetermined time Tth2 preset as a time considered to be operated at the intention of the operator. When Tc34 (t) is greater than the 2 nd predetermined time Tth2 (when the operation time of lever 34 exceeds Tth 2), yes is determined in step S507, and the process proceeds to step S511, and the power reduction control (described later) is released. If Tc34 (t) is equal to or less than the 2 nd predetermined time Tth2 (if the operation time of lever 34 is less than Tth 2), no is determined in step S507, and the process proceeds to step S512, where the power reduction control is continued. The 2 nd predetermined time Tth2 is shorter than the 1 st predetermined time Tth1, and is, for example, 2 to 3 seconds.

In step S508, the power reduction determination portion 50c-5 determines whether the 2 nd lever no-operation flag F34 (t) is true. If the 2 nd lever no-operation flag F34 (t) is true (if the lever 34 is not operated), the process proceeds to step S509. If the 2 nd lever no-operation flag F34 (t) is false (if the lever 34 is being operated), the process proceeds to step S515, and the power reduction control (described later) is released.

Here, the case where no is determined in step S508 is the case where no is determined in both step S505 and step S508, and the 1 st release condition is satisfied in which the 1 st and 2 nd operation levers 14 and 34 are simultaneously operated in the state where the power is reduced. In the present embodiment, when the 1 st release condition is satisfied in which the 1 st and 2 nd operation levers 14 and 34 are simultaneously operated in this way, the power reduction control is released.

In step S509, the power reduction determination portion 50c-5 determines whether the 1 st lever operation time Tc14 (t) is greater than the 2 nd predetermined time Tth2. If the 1 st lever operation time Tc14 (t) is longer than the 2 nd predetermined time Tth2 (if the lever operation time 14 exceeds Tth2, it is determined that the process proceeds to step S513 and the power reduction control (described later) is released, and if the 1 st lever operation time Tc14 (t) is equal to or shorter than the 2 nd predetermined time Tth2 (if the lever operation time 14 is shorter than Tth 2), it is determined that the process proceeds to step S514 and the power reduction control is continued.

Here, the case where no is determined in step S506, the case where yes is determined in step S507, and the case where yes is determined in step S508, the case where yes is determined in step S509, is a case where one of the 1 st and 2 nd levers 14, 34 is operated in the state where the power is reduced, and the 2 nd release condition is satisfied in which the operation state of the one lever continues for the 2 nd predetermined time Tth2. In the present embodiment, even when the 1 st release condition is not satisfied, the power reduction control is released when one of the 1 st and 2 nd levers 14 and 34 is operated and the 2 nd release condition is satisfied in which the operation state of the one lever continues for the 2 nd predetermined time Tth2.

In step S510, the power reduction determination unit 50c-5 sets the power reduction flag F50 (t) to true, and reduces the target rotation speed of the engine 6 to be lower than the normal target rotation speed indicated by the target rotation speed indication device 77. Then, the target rotation speed information is transmitted to the rotation speed control device 7. The rotation speed control device 7 reduces the rotation speed of the engine 6 by reducing the amount of fuel supplied to the engine 6. The processing of the same content as that of step S510 is also performed in step S512 and step S514. In this way, the power reduction determination unit 50c-5 performs power reduction control in steps S510, S512, and S514.

In step S511, the power-reduction determination unit 50c-5 sets the power-reduction flag F50 (t) to false, and sets the target rotation speed of the engine 6 to the normal value instructed by the target rotation speed instruction device 77. Then, the target rotation speed information is transmitted to the rotation speed control device 7. The rotation speed control device 7 increases the rotation speed of the engine 6 by increasing the amount of fuel supplied to the engine 6. The processing similar to that of step S511 is also performed in step S513 and step S515. In this way, the power reduction determination unit 50c-5 releases the power reduction control in steps S511 and S513. In step S515, the power reduction control is released when the power reduction control is not performed so far, and the power reduction control is released when the power reduction control is performed so far.

Next, an example of transition of the operation pressure and the target rotation speed in embodiment 1 will be described with reference to fig. 13. Fig. 13 is a time chart showing an example of transition between the operating pressure and the target rotational speed when the levers 14 and 34 are operated. The upper graph of fig. 13 shows a time change based on the operating pressure P17b (t) of the lever 14, the center graph shows a time change based on the operating pressure P37b (t) of the lever 34, and the lower graph shows a time change of the target rotation speed. The horizontal axis is time (seconds) for all charts. The threshold value Pth of the operation pressure is also described in both the upper graph and the center graph.

At time t0, lever 14 is operated in forward direction 14b, and lever 34 is operated in rightward direction 34 b. Therefore, the pressure values of the operating pressures P17b (t) and P37b (t) both exceed the threshold value Pth, and the pressure value of the other operating pressure, not shown, is 0. At this time, the process of step S515 in fig. 12 is performed (s502→s503→s504→s515), and the target rotation speed is the normal value Nh instructed by the target rotation speed instruction device 77. That is, the power reduction control (automatic idle control) is released.

The operation pressures P17b (t), P37b (t) are each greater than the threshold value Pth from the time t0 to the time t 1. In this case, the process of step S515 in fig. 12 is performed (s502→s503→s504→s515), and the target rotation speed is set to the normal value Nh.

At time t1, the levers 14 and 34 return to the neutral positions, and the operating pressures P17b (t) and P37b (t) are each values smaller than the threshold value Pth. Therefore, after the processing of step S515 is performed until the 1 st predetermined time Tth1 seconds from the time t1, the processing of step S510 of fig. 12 is performed (s502→s503→s510), and the target rotation speed is reduced from the normal value Nh and is set to a small value Nl for the power reduction control (automatic idle control).

At time t2, the lever 34 is operated, and only the operating pressure P37b (t) is greater than the threshold Pth. At this time, the process of step S512 in fig. 12 (s502→s503→s504→s505→s506→s507→s512) is performed, and the power reduction control is continued. If the state continues for the 2 nd predetermined time Tth2 seconds or longer and the aforementioned 2 nd release condition is satisfied, the process of step S511 in fig. 12 is performed (s502→s503→s504→s505→s506→s507→s511), the target rotation speed is set to the normal value Nh, and the power reduction control is released.

When the lever 34 is erroneously operated and the lever 34 is returned to the neutral position before the 2 nd predetermined time Tth2 seconds is reached, the no-operation time Tu34 (t) becomes 0. At this time, the determination of step S503 of fig. 12 is still yes, and the determination of step S506 is still yes. Therefore, the process of step S510 (s502→s503→s504→s505→s506→s510) is performed, and the power reduction control is continued.

Then, at time t2a, the operation pressure P37b (t) decreases again, and the operation pressures P17b (t) and P37b (t) are each values smaller than the threshold value Pth. If this state continues for the 1 st predetermined time Tth1 second or longer, the process of step S510 of fig. 12 is performed (s502→s503→s510), and the target rotation speed is set to a small value Nl for the power reduction control. Then, the operation pressures P17b (t), P37b (t) become larger than the threshold value Pth at the same time at time t 3. At this time, the 1 st release condition is satisfied, the process of step S515 in fig. 12 (s502→s503→s504→s505→s508→s515) is performed, the target rotation speed is set again to the normal value Nh without hysteresis, and the power reduction control is released.

As described above, according to the present embodiment, when the 1 st release condition is satisfied (s502→s503→s504→s505→s508→s515 in fig. 12) in which the two levers 14, 34 of the lever devices 114, 134 are simultaneously operated in the power-reduced state of the engine 6 and the hydraulic pump 1, the controller 50 determines that the operator "has the intention to release the power reduction", and releases the power-reduction control. This makes it possible to perform the power reduction control when the two levers 14, 34 are not operated, and to cancel the power reduction control by simultaneously operating only the two levers 14, 34 in the power reduction state. Further, since the power reduction control is released by simultaneously operating only the two levers 14 and 34 in the power reduction state, the operation can be smoothly shifted to the desired operation when the normal power state is restored.

On the other hand, when one of the levers is operated, the power reduction control is released when the 2 nd release condition is satisfied in which one of the levers is operated for a time longer than the 2 nd predetermined time Tth2 (s502→s503→s504→s505→s506→s507→s511, or s502→s503→s504→s505→s508→s509→s513). Thus, when any one of the levers is erroneously operated for a short time (time equal to or less than the predetermined time Tth2 of fig. 2), the power reduction control is not released, and the normal power control state can be prevented from being restored. Further, since the power reduction control is released by only continuing to operate one operation lever for the 2 nd predetermined time Tth2 or longer, the operation can be smoothly shifted to the desired operation when the normal power state is restored.

Modification 1 >

In embodiment 1, as described above, the controller 50 is configured to cancel the power reduction control when the two levers 14 and 34 of the lever devices 114 and 134 are simultaneously operated in the power reduced state of the engine 6 and the hydraulic pump 1 and when one lever is continuously operated for the 2 nd predetermined time Tth2 or longer. However, the controller 50 may be configured to release the power reduction control only when one of them, for example, only the two levers 14 and 34 of the lever devices 114 and 134 are simultaneously operated in the power reduction state of the engine 6 and the hydraulic pump 1. In this case, too, the effect that the power reduction control can be performed when the operation lever is not operated as described above, and the return to the normal power state when the operation lever is erroneously moved can be suppressed, and the desired operation can be smoothly shifted to the normal power state when the operation lever is returned to the normal power state can be obtained.

Modification 2 >

In embodiment 1, when the 1 st release condition is satisfied in which the levers 14 and 34 are simultaneously operated, the controller 50 releases the power restriction control even when the lever 34 operates the rotary motor 43. However, even when the 1 st release condition is satisfied when the levers 14 and 34 are simultaneously operated, the power limiting control may not be released when the lever 34 operates the rotary motor 43, and the power reducing control may be released only when the lever 34 does not operate the rotary motor 43.

Such a modification will be described with reference to fig. 14 and 15.

Fig. 14 is a block diagram similar to fig. 6 showing the function of the power calculation unit 50c of the controller 50 in the present embodiment.

In fig. 14, the power calculation unit 50c (see fig. 5) includes a power reduction determination unit 50c-5D, and in the power reduction determination unit 50c-5D, sensor values P47l (t) and P47r (t) of pressure sensors 47l and 47r for detecting the operation states of the operation lever 34 in the front-rear direction corresponding to the operation instructions of the right rotation and the left rotation of the rotation motor 43 are input in addition to the 1 st lever no-operation flag F14 (t), the 1 st lever no-operation time Tu14 (t), the 1 st lever operation time Tc14 (t), the 2 nd lever no-operation flag F34 (t), the 2 nd lever no-operation time Tu34 (t), the 2 nd lever operation time Tc34 (t), and the switch flag Fsw (t).

Fig. 15 is a flowchart showing the operation flow of the power reduction determination unit 50c-5D shown in fig. 14.

In fig. 15, step S530 is added to the operation flow of the power reduction determination unit 50c-5D, and in step S508, the power reduction determination unit 50c-5D determines no if the 2 nd lever no-operation flag F34 (t) is false, and the flow of the processing proceeds to step S530.

In step S530, the power reduction determination unit 50c-5D determines whether the sensor value P47l (t) is greater than the threshold value Pth, and whether the sensor value P47r (t) is greater than the threshold value Pth. If it is determined that either one of the sensor value P47l (t) and the sensor value P47r (t) is greater than the threshold value Pth (when the lever 34 operates the rotary motor 43), the process proceeds to step S514, and if it is determined that neither one of the sensor value P47l (t) nor the sensor value P47r (t) is greater than the threshold value Pth (when the lever 34 does not operate the rotary motor 43), the process proceeds to step S515.

In step S514, the power reduction determination unit 50c-5D sets the power reduction flag F50 (t) to true, and reduces the target rotation speed of the engine 6 to a value lower than the normal value indicated by the target rotation speed indication device 77, thereby performing power reduction control. In step S515, the power-reduction determination unit 50c-5D sets the power-reduction flag F50 (t) to false, and sets the target rotation speed of the engine 6 to the normal value indicated by the target rotation speed indication device 77.

As described above, in the present modification, if it is determined in step S508 that the 1 st release condition is satisfied in which the 1 st and 2 nd levers 14 and 34 are simultaneously operated in the power-reduced state, and if it is determined in step S530 that the 2 nd lever 34 does not operate the rotary motor 43, the power-reduction control is released.

In the modified example having such a configuration, as in embodiment 1, the return to the normal power state is suppressed when the operation lever is erroneously moved, and the operation can be smoothly shifted to the desired operation when the operation lever is returned to the normal power state, and the upper rotating body 102 does not perform the rotating operation when both the operation levers 14 and 34 are simultaneously operated to release the power lowering control, so that the operability can be prevented from deteriorating.

Modification 3 >

In embodiment 1, the description has been made of the case where the operation lever devices 114 and 134 are hydraulic pilot systems including pilot valves, and the operation state detection devices are pressure sensors 17b, 17r, 27b, 27r, 37b, 37r, 47l, and 47r that detect the operation pressures generated by the pilot valves, but the operation state detection devices may be other configurations. For example, a signal pressure generating line that guides the oil discharged from the pilot pump 51 to the tank 5 may be provided, a plurality of signal pressure generating valves may be disposed in the signal pressure generating line, the signal pressure generating valves may be switched by the operation pressure generated by the pilot valve, and the pressure of the signal pressure generating line that changes by opening or closing the signal pressure generating valves may be detected, thereby detecting the operation state of the lever device. In this case, the pressure sensor detects the operation state of the lever devices 114 and 134 in the same manner as the pressure sensor detecting the operation pressure, and the same effects as those of embodiment 1 can be obtained.

< embodiment 2 >

Embodiment 2 of the present invention will be described with reference to fig. 16 to 19. Note that this embodiment will mainly be described in the different portions from embodiment 1, and the description of the same portions as embodiment 1 will be omitted.

First, the configuration of the drive system in embodiment 2 will be described. Fig. 16 is a diagram showing a configuration of a drive system according to the present embodiment.

In fig. 16, the drive system of embodiment 2 is different from embodiment 1 in that the hydraulic pump 1 is driven by a dc electric motor 60A, the electric motor 60A is electrically connected to a battery 62 and the electric motor 60A is driven by electric power supplied from the battery 62, battery output from the battery 62 is controlled by a battery output control panel 63, the battery output control panel 63 is electrically connected to the controller 50A, and the battery output control panel 63 controls output electric power based on target battery output information transmitted from the controller 50A.

Here, the battery 62 is an electric power supply device, and the electric power supply device and the electric motor 60A constitute a power source.

Next, the function of the controller 50A in embodiment 2 will be described. Fig. 17 is a block diagram showing the function of the controller 50A.

In fig. 17, a controller 50A in embodiment 2 is different from embodiment 1 in that a power calculation unit 50cA is provided in place of the power calculation unit 50c, and the power calculation unit 50cA receives pressure information and a switch flag transmitted from the sensor signal conversion unit 50A, and constant information and table information transmitted from the constant/table storage unit 50b, and calculates a target value of battery output (target battery output). The target battery output calculated by the power calculation unit 50cA is sent to a battery output control panel 63, and the battery output control panel 63 controls the output of the battery 62 based on the value.

Next, the function of the power calculation unit 50cA in embodiment 2 will be described. Fig. 18 is a block diagram showing the function of the power calculation unit 50 cA.

In fig. 18, the power calculation unit 50cA in embodiment 2 is different from embodiment 1 in that the power reduction determination unit 50c-5 is replaced with a power reduction determination unit 50c-5A, and the power reduction determination unit 50c-5A outputs the target battery output. The input of the power reduction determination unit 50c-5A is the same as that of the power reduction determination unit 50 c-5.

Next, the operation flow of the power reduction determination unit 50c-5A in embodiment 2 will be described. Fig. 19 is a flowchart showing the operation flow of the power reduction determination unit 50 c-5A.

In fig. 19, the operation flow of the power reduction determination unit 50c-5A in embodiment 2 differs from that in embodiment 1 in that the process of step S516 is executed instead of step S510, the process of step S517 is executed instead of step S511, the process of step S518 is executed instead of step S512, the process of step S519 is executed instead of step S513, the process of step S520 is executed instead of step S514, and the process of step S521 is executed instead of step S515.

In step S516, the power reduction determination unit 50c-5A sets the power reduction flag F50 (t) to true, and reduces the target battery output to be lower than normal. Then, the target battery output is sent to the battery output control board 63. Step S518 and step S520 also perform the same processing as step S516.

In step S517, the power-reduction determination unit 50c-5A sets the power-reduction flag F50 (t) to false and sets the target battery output to a value at normal times. Then, the target battery output is sent to the battery output control board 63. Step S519 and step S521 also perform the same processing as step S517.

In embodiment 2 configured as described above, even when the power source is configured by the battery 62 (power supply device), the electric motor 60A, and the hydraulic pump 1, the controller 50 determines that the operator "has intention to cancel the power reduction" and releases the power reduction control when the 1 st release condition is satisfied in which both the operation levers 14, 34 of the operation lever devices 114, 134 are simultaneously operated in the power reduced state of the power source, or when the 2 nd release condition is satisfied in which one operation lever is continuously operated for the 2 nd predetermined time Tth2 or more, as in embodiment 1. This makes it possible to perform power reduction control when the operation lever is not operated, to suppress restoration to a normal power state when the operation lever is erroneously moved, and to smoothly shift to a desired operation when the operation lever is restored to the normal power state.

< modification >

In embodiment 2, the power source of the drive system is constituted by the direct-current electric motor 60A and the hydraulic pump, but an alternating-current electric motor may be used instead of the direct-current electric motor 60A. Fig. 20 is a diagram showing a modification of the drive system.

In fig. 20, the power source of the drive system is constituted by an ac electric motor 60B and a hydraulic pump 1. The hydraulic pump 1 is driven by an ac electric motor 60B, and the electric motor 60B is controlled by an inverter 61. The inverter 61 is electrically connected to the controller 50, and receives information of the target rotational speed from the controller 50. The controller 50 performs the same processing as the controller 50 shown in fig. 5, and calculates the target rotation speed. The inverter 61 is electrically connected to a battery 62, and receives electric power supplied to the electric motor 60B. In such a configuration, the same effects as those of embodiment 1 and embodiment 2 can be obtained.

Embodiment 3

Embodiment 3 of the present invention will be described with reference to fig. 21 to 28. In the present embodiment, the power reduction is performed by reducing the potential in the drive system.

First, the configuration of the drive system in embodiment 3 will be described. Fig. 21 is a diagram showing a configuration of a drive system according to the present embodiment.

In fig. 21, the controller 50C is electrically connected to an angle sensor 72, an angle sensor 73, an angle sensor 74, an angle sensor 75, and a switch 76, which will be described later, and receives signals of angle information and switch information from these sensors 72 to 75 and the switch 76. Based on these signals, the controller 50C calculates a target battery output of the battery 62, and transmits the target battery output to a battery output control panel 63 electrically connected to the controller 50C. The battery output control panel 63 controls the battery 62 so as to be the target battery output.

The battery 62 is connected to a positive electrode-side electric wire 81 and a negative electrode-side electric wire 82. The positive electrode side electric wire 8 and the negative electrode side electric wire 82 are connected in parallel with inverters 83, 84, 85, 86.

The inverter 83 drives the electric motor 87, and the electric motor 87 further drives the cylinder 91 (boom cylinder). The cylinder 91 converts the rotational motion of the electric motor 87 into linear motion by a rack and pinion mechanism or the like, and expands and contracts. The inverter 83 receives the signal transmitted from the angle sensor 72 and controls the electric motor 87 so as to have a rotational speed corresponding to the information.

The inverter 84 drives the electric motor 88, and the electric motor 88 further drives the cylinder 92 (arm cylinder). The cylinder 92 converts the rotational motion of the electric motor 88 into linear motion by a rack and pinion mechanism or the like, and expands and contracts. The inverter 84 receives the signal transmitted from the angle sensor 73 and controls the electric motor 88 so as to have a rotational speed corresponding to the information.

The inverter 85 drives the electric motor 89, and the electric motor 89 further drives the cylinder 93 (bucket cylinder). The cylinder 93 converts the rotational motion of the electric motor 89 into linear motion by a rack and pinion mechanism or the like, and expands and contracts. The inverter 85 receives the signal transmitted from the angle sensor 74 and controls the electric motor 89 so as to have a rotational speed corresponding to the information.

Inverter 86 drives electric motor 90. The inverter 86 receives the signal transmitted from the angle sensor 75 and controls the electric motor 90 (rotary motor) so as to have a rotational speed corresponding to the information.

Here, the battery 62 is an electric power supply device that constitutes a power source. The electric motor 87 and the cylinder 91, the electric motor 88 and the cylinder 92, the electric motor 89 and the cylinder 93, and the electric motor 90 constitute a plurality of actuators that operate by receiving power from a power source, and the inverters 83, 84, 85, 86 constitute a power distribution device that distributes power to the plurality of actuators (the electric motor 87 and the cylinder 91, the electric motor 88 and the cylinder 92, the electric motor 89 and the cylinder 93, and the electric motor 90). The lever devices 314 and 334 described later instruct the power distribution devices ( inverters 83, 84, 85, and 86) to distribute the power to the plurality of actuators (electric motor 88 and cylinder 92, electric motor 89 and cylinder 93, and electric motor 90).

Next, the configuration of the operation signal system in embodiment 3 will be described with reference to fig. 22 and 23.

Fig. 22 is a diagram showing the configuration of the operation signal system of the drive system in embodiment 3.

In fig. 22, the operation signal system in embodiment 3 is different from the operation signal system in embodiment 1 shown in fig. 4 in that the operation signal system is provided with a lever device 314 instead of the lever device 114 and a lever device 334 instead of the lever device 134. The lever devices 314 and 334 are of an electric lever type, and the lever device 314 includes a lever 14, an angle sensor 72 that outputs information on angles of the front direction 14b and the rear direction 14r, and an angle sensor 73 that outputs information on angles of the left direction 24b and the right direction 24 r. The lever device 334 includes an angle sensor 74 that outputs information on angles of the right direction 34b and the left direction 34r, and an angle sensor 75 that outputs information on angles of the front direction 44l and the rear direction 44 r.

The angle sensors 72, 73, 74, 75 constitute a plurality of operation state detection means for detecting the operation states of the operation lever means 314, 334.

The angle sensors 72, 73, 74, 75 are electrically connected to the controller 50C. The angle sensor 72 is also electrically connected to the inverter 83, and transmits information of the angle. The angle sensor 73 is also electrically connected to the inverter 85, and transmits information of the angle. The angle sensor 74 is also electrically connected to the inverter 84, and transmits information on the angle. The angle sensor 75 is also electrically connected to the inverter 86, and transmits information on the angle.

Fig. 23 is a diagram showing a relationship between the inclination of the lever 14 in the front- rear direction 14b, 14r and the target rotation speed of the electric motor 87. As shown in fig. 23, the target rotation speed of the electric motor 87 increases in the clockwise direction as the lever 14 is tilted in the forward direction 14 b. In addition, the target rotation speed of the electric motor 87 becomes 0 when no operation is performed. The target rotation speed of the electric motor 87 becomes larger in the counterclockwise direction as the lever 14 is tilted in the backward direction 14 r.

Similarly, the target rotational speeds of the electric motors 88, 89, 90 are changed when the lever 14 is tilted in the rightward direction 24 r/leftward direction 24b, and when the lever 34 is tilted in the rightward direction 34 b/leftward direction 34r and in the forward direction 44 l/backward direction 44 r.

Next, the function of the controller 50C in embodiment 3 will be described. Fig. 24 is a block diagram showing the function of the controller 50C.

In fig. 24, a controller 50C in embodiment 3 is different from embodiment 2 in that a sensor signal conversion unit 50aC is provided in place of the sensor signal conversion unit 50a, and a power calculation unit 50cC is provided in place of the power calculation unit 50 cA.

The sensor signal conversion unit 50aC receives signals transmitted from the angle sensors 72 to 75 and the switch 76, and converts the signals into angle information and switch flag information. The sensor signal conversion unit 50aC transmits the converted angle information and the switch flag information to the power calculation unit 50cC.

The constant/table storage unit 50b stores the constants and tables necessary for calculation in advance, and sends them to the power calculation unit 50cC.

The power calculation unit 50cC receives the angle information and the switch flag information transmitted from the sensor signal conversion unit 50aC, and the constant information and the table information transmitted from the constant/table storage unit 50b, and calculates the target battery output of the battery 62. The power calculation unit 50cC outputs the target battery output value to the battery output control panel 63. The battery output control panel 63 controls the output of the battery 62 based on the value.

The conversion processing of the sensor signal in the sensor signal conversion unit 50aC is described. Fig. 25 is a diagram illustrating the conversion processing performed by the sensor signal conversion unit 50aC, and is a diagram when the lever 14 is tilted in the forward direction 14b or the backward direction 14 r.

As shown in fig. 25, the sensor signal conversion unit 50aC converts such that the sensor value a72 (t) becomes larger as the lever 14 is tilted in the forward direction 14 b. In addition, the conversion is performed such that the sensor value a72 (t) becomes 0 when no operation is performed. When the lever 14 is inclined in the backward direction 14r, the sensor value a72 (t) becomes a negative value. The same applies to the case where the lever 14 is inclined in the rightward direction 24 r/leftward direction 24b, and the case where the lever 34 is inclined in the rightward direction 34 b/leftward direction 34r and the forward direction 44 l/backward direction 44 r. The sensor value a72 (t) is a value corresponding to the target rotation speed of the electric motor 87 of fig. 23.

Next, the function of the power calculation unit 50cC in embodiment 3 will be described. Fig. 26 is a block diagram showing the function of the power calculation unit 50 cC. Let the sampling time of the controller 50C be Δt.

In fig. 26, the power calculation unit 50cC in embodiment 3 differs from embodiment 1 in that a 1 st lever operation state determination unit 50C-1C is provided in place of the 1 st lever operation state determination unit 50C-1, a 2 nd lever operation state determination unit 50C-2C is provided in place of the 2 nd lever operation state determination unit 50C-2, and a power reduction determination unit 50C-5C similar to embodiment 2 is provided in place of the power reduction determination unit 50C-5.

Next, the function of the 1 st lever operation state determination unit 50C-1C in embodiment 3 will be described. Fig. 27 is a flowchart showing the operation flow of the 1 st lever operation state determination unit 50C-1C. This operation flow is repeatedly processed at the sampling time Δt during the operation of the controller 50, for example.

The operation flow of the 1 st lever operation state determination unit 50C-1C is different from that of the 1 st lever operation state determination unit 50C-1 in embodiment 1 shown in fig. 7 in that the processing from step S102 to step S105 is not performed, and the processing from step S101 proceeds to the processing from step S110 to step S111.

In step S110, the 1 st lever operation state determining section 50C-1C determines whether the absolute value of the sensor value a72 (t) is smaller than the threshold Ath. If the absolute value of the sensor value a72 (t) is smaller than the threshold Ath, the process advances to step S111. If the absolute value of the sensor value a72 (t) is equal to or greater than the threshold Ath, the determination is no, and the process proceeds to step S107.

In step S111, the 1 st lever operation state determining section 50C-1C determines whether the absolute value of the sensor value a73 (t) is smaller than the threshold Ath. If the absolute value of the sensor value a73 (t) is smaller than the threshold Ath, the process advances to step S106. If the absolute value of the sensor value a73 (t) is equal to or greater than the threshold Ath, the process advances to step S107.

The 1 st lever no-operation flag F14 (t) is set to true in step S106, and the 1 st lever no-operation flag F14 (t) is set to false in step S107. These flag information are sent to the 1 st lever operation time measuring section 50C-3 and the power reduction judging section 50C-5C.

Next, the function of the 2 nd lever operation state determination unit 50C-2C in embodiment 3 will be described. Fig. 28 is a flowchart showing the operation flow of the 2 nd lever operation state determination unit 50C-2C. This operation flow is repeatedly processed at the sampling time Δt during the operation of the controller 5, for example.

The operation flow of the 2 nd lever operation state determining unit 50C-2C is different from that of the 2 nd lever operation state determining unit 50C-2 in embodiment 1 shown in fig. 8 in that the processing of step S202 to step S205 is not performed, and the processing proceeds from step S201 to the processing of step S210 and step S211.

In step S210, the 2 nd lever operation state determining section 50C-2C determines whether the absolute value of the sensor value a74 (t) is smaller than the threshold Ath. If the absolute value of the sensor value a74 (t) is smaller than the threshold Ath, the process advances to step S211. If the absolute value of the sensor value a74 (t) is equal to or greater than the threshold Ath, the process advances to step S207.

In step S211, the 2 nd lever operation state determining section 50C-2C determines whether the absolute value of the sensor value a75 (t) is smaller than the threshold Ath. If the absolute value of the sensor value a75 (t) is smaller than the threshold Ath, it is determined as yes, and the process proceeds to step S206. If the absolute value of the sensor value a75 (t) is equal to or greater than the threshold Ath, the determination is no, and the process proceeds to step S207.

The 2 nd rod no-operation flag F34 (t) is set to true in step S206, and the 2 nd rod no-operation flag F34 (t) is set to false in step S207. These flag information are sent to the 2 nd lever operation time measuring section 50C-4 and the power reduction judging section 50C-5C.

The 1 st lever operation state determination unit 50C-1C thus determines whether the lever 14 is being operated based on the sensor value a72 (t) and the sensor value a73 (t), and outputs the 1 st lever no-operation flag F14 (t). The 2 nd lever operation state judging section 50C-2C judges whether the lever 34 is being operated or not based on the sensor value a74 (t) and the sensor value a75 (t), and outputs the 2 nd lever no-operation flag F34 (t).

In the 1 st lever operation time measuring unit 50c-3, the 1 st lever non-operation time Tu14 (t) and the 1 st lever operation time Tc14 (t) are measured. These pieces of time information are sent to the power reduction judgment section 50C-5C.

In the 2 nd lever operation time measuring unit 50c-4, the 2 nd lever non-operation time Tu34 (t) and the 2 nd lever operation time Tc34 (t) are measured. These pieces of time information are sent to the power reduction judgment section 50C-5C.

The power reduction determination unit 50C-5C determines whether or not to reduce the battery output, and outputs the target battery output and the power reduction flag F50 (t), in the same manner as the power reduction determination unit 50C-5A of embodiment 2 shown in fig. 18, in the order of the flowchart shown in fig. 19. The target battery output is sent to a battery output control board 63, and the battery output control board 63 controls the battery 62 so as to be the target battery output.

In embodiment 3 configured as described above, even when the power source is constituted by the battery 62 (electric power supply device) and the actuator is constituted by the electric actuator including the electric motors 87 to 90, the controller 50 determines that the operator "has intention to cancel the power reduction" and releases the power reduction control when the 1 st release condition is satisfied in which the two levers 14 and 34 of the lever devices 314 and 334 are simultaneously operated in the power reduction state of the power source or when the 2 nd release condition is satisfied in which one lever is continuously operated for the 2 nd predetermined time Tth2 or more, as in embodiment 1. This makes it possible to perform power reduction control when the operation lever is not operated, to suppress restoration to a normal power state when the operation lever is erroneously moved, and to smoothly shift to a desired operation when the operation lever is restored to the normal power state.

Description of the reference numerals

1: hydraulic pump (Power source)

2: pipeline

3: overflow valve

4: overflow pipeline

5: oil tank

6: engine (Power source)

7: rotation speed control device

8: series pipeline

9: parallel pipeline

10. 20, 30, 40: one-way valve

11. 21, 31, 41: pipeline

12. 22, 32, 42: direction control valve (Power distribution device)

12r, 12b, 22r, 22b, 32r, 32b, 42r, 42l: pilot pipeline

13. 23, 33: cylinder (actuator)

13B, 23B, 33B: cylinder bottom pipeline

13R, 23R, 33R: piston rod pipeline

13T, 23T, 33T, 43T: oil tank pipeline

13C, 23C, 33C, 43C: intermediate bypass line

14: operating lever (No. 1 operating lever)

15r, 15b, 25r, 25b, 35r, 35b, 45r, 45l: pilot valve

16r, 16b, 26r, 26b, 36r, 36b, 46r, 46l: pipeline

17r, 17b, 27r, 27b, 37r, 37b, 47l, 47r: pressure sensor (operating state detecting device)

18. 28, 38, 48: pipeline

19. 29, 39, 49: pipeline

34: operating lever (2 nd operating lever)

43: hydraulic motor

43L: left rotary pipeline

43R: right rotary pipeline

50: controller for controlling a power supply

51: pilot pump

52: pilot pipeline

53: overflow valve

60A: electric motor (DC) (Power source)

60B: electric motor (AC) (Power source)

61: inverter with a power supply

62: accumulator (electric power supply device; power source)

63: storage battery output control panel

72. 73, 74, 75: angle sensor (operating state detecting device)

76: switch

81: positive electrode side wire

82: negative electrode side wire

83. 84, 85, 86: inverter (Power distribution device)

87. 88, 89, 90: electric motor (AC) (actuator)

91. 92, 93: cylinder (actuator)

94. 95, 96, 97: throttle part

114. 134: operating lever device

314. 334, 334: and a lever device.

Claims (6)

1. A construction machine is provided with:

a power source;

a plurality of actuators that operate by receiving power output from the power source;

a plurality of levers operable to indicate an amount of the power dispensed to the plurality of actuators;

a plurality of operation state detection means for detecting operation states of the plurality of operation levers; and

a controller for controlling the power source,

the plurality of operation levers have a 1 st operation lever and a 2 nd operation lever for operating different ones of the plurality of actuators,

the controller performs power reduction control for reducing the power when the no-operation state of the 1 st operation lever and the 2 nd operation lever is continued,

the construction machine is characterized in that,

the controller is configured to cancel the power reduction control when the operation state of the 1 st and 2 nd operation levers detected by the operation state detection means satisfies a 1 st cancellation condition indicating an amount of the power allocated to the plurality of actuators when the 1 st and 2 nd operation levers are simultaneously operated in a state in which the power is reduced by the power reduction control.

2. A construction machine is provided with:

a power source;

a plurality of actuators that operate by receiving power output from the power source;

a plurality of levers indicating an amount of the power allocated to the plurality of actuators;

a plurality of operation state detection means for detecting operation states of the plurality of operation levers; and

a controller for controlling the power source,

the plurality of operation levers have a 1 st operation lever and a 2 nd operation lever for operating different ones of the plurality of actuators,

the controller performs power reduction control for reducing the power when the no-operation state of the 1 st operation lever and the 2 nd operation lever is continued,

the construction machine is characterized in that,

the controller releases the power reduction control when one of the 1 st and 2 nd levers is operated and the operation state of the one lever continues for a 2 nd release condition for a predetermined time in a state where the power is reduced by the power reduction control.

3. The construction machine according to claim 1, wherein the working machine is,

comprises a lower traveling body, an upper rotating body rotatably mounted on the lower traveling body, and a front working machine rotatably mounted on the front part of the upper rotating body in the up-down direction,

The plurality of actuators includes a rotation motor that rotates the upper rotating body with respect to the lower traveling body, and a 1 st front actuator, a 2 nd front actuator, and a 3 rd front actuator that drive the front working machine,

the 1 st operation lever is an operation lever for operating the 1 st front actuator and the 2 nd front actuator, the 2 nd operation lever is an operation lever for operating the rotary motor and the 3 rd front actuator,

the plurality of operation state detection means includes 1 st operation state detection means for detecting an operation state of the 1 st operation lever when the 1 st operation lever operates the 1 st front actuator, 2 nd operation state detection means for detecting an operation state of the 1 st operation lever when the 1 st operation lever operates the 2 nd front actuator, 3 rd operation state detection means for detecting an operation state of the 2 nd operation lever when the 2 nd operation lever operates the 3 rd front actuator, and 4 th operation state detection means for detecting an operation state of the 2 nd operation lever when the 2 nd operation lever operates the rotary motor,

the controller is configured to cancel the power reduction control when the 2 nd operation lever does not actuate the rotary motor, when the 1 st operation lever and the 2 nd operation lever are simultaneously operated to indicate the 1 st release condition of the power for the allocated amount of the plurality of actuators, based on detection results of the 1 st operation state detection means, the 2 nd operation state detection means, the 3 rd operation state detection means, and the 4 th operation state detection means.

4. The construction machine according to claim 1, wherein the working machine is,

the power source includes an engine and a hydraulic pump,

the power source generates the power by driving the hydraulic pump by the engine,

the controller performs the power reduction control by reducing the rotation speed of the engine.

5. The construction machine according to claim 1, wherein the working machine is,

the power source includes an electric power supply device, an electric motor and a hydraulic pump,

the power source drives the electric motor by electric power supply from the electric power supply device, generates the power by driving the hydraulic pump by the electric motor,

the controller performs the power reduction control by reducing the rotation speed of the electric motor by reducing the supply of electric power to the electric motor.

6. The construction machine according to claim 1, wherein the working machine is,

the power source includes an electric power supply device,

the actuator is an electric actuator comprising an electric motor,

the power source drives the electric actuator by power supply from the power supply device,

the controller performs the power reduction by reducing the rotation speed of the electric motor by reducing the electric power supplied from the electric power supply device to the electric motor.

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