WO2020065739A1 - Work machine - Google Patents

Abstract

A hydraulic shovel 1 comprising a controller (40) that calculates the speed of an arm cylinder (6) on the basis of information on the amount an operation device (45b) is manipulated when the operation device (45b) is operated and correlation data in which the relationship between the information on the amount the operation device (45b) is manipulated and the arm cylinder (6) speed is defined, and that executes machine control for a boom cylinder (5) according to that calculation result and a preset condition, wherein the controller (40) modifies the correlation data on the basis of either of a target speed and the actual speed of an engine (18). Thereby, machine control precision can be stabilized regardless of the engine speed.

Description

Work machine

The present invention relates to a work machine that controls at least one of a plurality of hydraulic actuators according to predetermined conditions when operating an operating device.

技術 Machine Control (MC) is a technique for improving the working efficiency of a working machine (for example, a hydraulic shovel) including a working device (for example, a front working device) driven by a hydraulic actuator. MC is a technique for assisting the operation of an operator by executing semi-automatic control for operating a working device according to predetermined conditions when the operating device is operated by an operator.

For example, WO 2015/129930 pamphlet discloses a technique of MC of a front working device so as to move a cutting edge of a bucket along a reference plane. In this document, as for the correlation data between the boom cylinder speed and the operation command value for operating the boom cylinder, a plurality of correlation data corresponding to the type of the bucket is stored, and the correlation data is stored according to the type of the bucket attached to the front. By controlling using the correlation data, the decrease in excavation accuracy is suppressed.

WO 2015/129930 pamphlet

Some work machines include an engine speed dial (engine control dial) and a work mode selection switch as a means by which the operator can change the engine speed. When the operator operates the engine speed dial, it can be adjusted to an arbitrary engine speed. Further, by operating the work mode selection switch to select the economy mode in which the upper limit of the engine speed is restricted, fuel consumption and noise can be reduced.

作業 Thus, work machines are sometimes used at low engine speeds for the purpose of reducing fuel consumption and noise. When the rotation speed of the engine decreases, the rotation speed of the pump driven by the engine also decreases, and the discharge flow rate of the pump also decreases. As a result, the actuator speed decreases.

On the other hand, in Patent Document 1, when performing MC, the boom cylinder speed is calculated using correlation data between the operation command value and the boom cylinder speed. However, when the engine speed changes, the actuator speed changes as described above. Therefore, the correlation between the operation command value and the boom cylinder speed also changes. At this time, since the boom cylinder speed is calculated based on correlation data different from the actual state, the behavior of the bucket in the MC may not be stable, and the excavation accuracy may be reduced.

A similar problem arises when changing the engine speed by changing the mode, for example, by providing a mode for restricting the upper limit of the engine speed for the purpose of reducing fuel consumption and noise as the MC mode. Can occur.

An object of the present invention is to provide a working machine capable of suppressing a decrease in the accuracy of the MC even when the rotation speed of the prime mover that drives the hydraulic pump changes when the MC is performed.

In order to achieve the above object, the present invention provides a motor, a hydraulic pump driven by the motor, a plurality of hydraulic actuators driven by hydraulic oil discharged from the hydraulic pump, and a plurality of hydraulic actuators driven by the plurality of hydraulic actuators. A working device to be operated, an operating device for instructing the operation of the plurality of hydraulic actuators in accordance with an operation of an operator, a speed of a hydraulic actuator corresponding to an operation of the operating device among the plurality of hydraulic actuators, A storage device that stores correlation data indicating a relationship with the operation amount information of the plurality of hydraulic actuators, based on the operation amount information of the operation device and the correlation data when operating the operation device. The speed of the hydraulic actuator corresponding to the operation of the operating device is calculated, and the calculation result is compared with a predetermined condition. And a control device for controlling at least one of the plurality of hydraulic actuators according to the following. The control device further includes: a controller configured to generate the correlation data based on one of a target rotation speed and an actual rotation speed of the prime mover. I decided to change it.

According to the present invention, the accuracy of MC can be stabilized irrespective of the rotation speed of the prime mover.

FIG. 1 is a configuration diagram of a hydraulic shovel according to an embodiment of the present invention. The figure which shows the controller of the hydraulic shovel which concerns on embodiment of this invention with a hydraulic drive. FIG. 2 is a detailed view of a front control hydraulic unit according to the embodiment of the present invention. FIG. 1 is a hardware configuration diagram of a controller of a hydraulic shovel according to an embodiment of the present invention. FIG. 2 is a diagram showing a coordinate system and a target surface in the hydraulic shovel of FIG. 1. The functional block diagram of the controller of the hydraulic shovel of FIG. FIG. 3 is a functional block diagram of an MC control unit according to the first embodiment of the present invention. 5 is a flowchart of boom raising control by a boom control unit according to the embodiment of the present invention. FIG. 4 is a diagram illustrating a relationship between a cylinder speed and an operation amount according to the embodiment of the present invention. The figure which shows the relationship between the limit value ay of the vertical component and the distance D of the bucket toe speed which concern on embodiment of this invention. FIG. 9 is a functional block diagram of an MC control unit according to a second embodiment of the present invention. FIG. 13 is a functional block diagram of an MC control unit according to a third embodiment of the present invention. FIG. 9 is a diagram illustrating a relationship between an engine speed and a correction coefficient according to a third embodiment of the present invention. FIG. 7 is a functional block diagram of an MC control unit according to a modification of the first embodiment of the present invention. FIG. 14 is a functional block diagram of an MC control unit according to a modification of the second embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following, a hydraulic excavator including the bucket 10 is exemplified as a working tool (attachment) at the tip of the working device, but the present invention may be applied to a working machine including an attachment other than the bucket. Furthermore, as long as it has a multi-joint type working device constituted by connecting a plurality of link members (attachment, arm, boom, etc.), it can be applied to a working machine other than a hydraulic shovel.

In this paper, the term “upper”, “upper”, or “lower” used together with a term indicating a certain shape (eg, target surface, design surface, etc.) means that “upper” means the shape of the certain shape. “Upper” means “above the surface” of the certain shape, and “below” means “lower than the surface” of the certain shape. In the following description, when there are a plurality of the same components, an alphabet may be added to the end of the reference numeral (number). However, the alphabet may be omitted and the plurality of components may be collectively described. is there. For example, when there are two pumps 2a and 2b, these may be collectively described as a pump 2.

<First embodiment>
<Basic configuration>
FIG. 1 is a configuration diagram of a hydraulic shovel according to a first embodiment of the present invention, FIG. 2 is a diagram illustrating a controller of the hydraulic shovel according to the embodiment of the present invention together with a hydraulic drive device, and FIG. FIG. 3 is a detailed view of a middle front control hydraulic unit 160.

In FIG. 1, the hydraulic excavator 1 includes an articulated front working device 1A and a vehicle body 1B. The vehicle body 1B includes a lower traveling body 11 that travels by left and right traveling hydraulic motors 3a and 3b, and an upper revolving body 12 mounted on the lower traveling body 11 and revolved by the revolving hydraulic motor 4.

The front working device 1A is configured by connecting a plurality of front members (the boom 8, the arm 9, and the bucket 10) that rotate vertically. The base end of the boom 8 is rotatably supported at the front of the upper swing body 12 via a boom pin. A base end of an arm 9 is rotatably connected to a distal end of the boom 8 via an arm pin, and a bucket 10 is rotatably connected to a distal end of the arm 9 via a bucket pin. The boom 8 is driven by a boom cylinder 5, the arm 9 is driven by an arm cylinder 6, and the bucket 10 is driven by a bucket cylinder 7.

The boom pin has a boom angle sensor 30, the arm pin has an arm angle sensor 31, and the bucket link 13 has a bucket angle sensor so that the rotation angles α, β, and γ (see FIG. 5) of the boom 8, the arm 9, and the bucket 10 can be measured. The upper revolving unit 12 is provided with a vehicle body inclination angle sensor 33 for detecting an inclination angle θ (see FIG. 5) of the upper revolving unit 12 (vehicle body 1B) with respect to a reference plane (for example, a horizontal plane). Each of the angle sensors 30, 31, and 32 can be replaced with an angle sensor (for example, an inertial measurement device) for a reference plane (for example, a horizontal plane).

An operating device 47a (FIG. 2) having a traveling right lever 23a (FIG. 1) for operating the traveling right hydraulic motor 3a (lower traveling body 11) is provided in a cab provided on the upper revolving unit 12. The operating device 47b (FIG. 2) for operating the traveling left hydraulic motor 3b (lower traveling body 11) having the left lever 23b (FIG. 1) and the operating right lever 1a (FIG. 1) are shared and the boom cylinder 5 ( The operating devices 45a and 46a (FIG. 2) for operating the boom 8) and the bucket cylinder 7 (bucket 10) and the operating left lever 1b (FIG. 1) share the arm cylinder 6 (arm 9) and the swing hydraulic motor 4 Operating devices 45b and 46b (FIG. 2) for operating the (upper revolving superstructure 12) are provided. Hereinafter, the traveling right lever 23a, the traveling left lever 23b, the operation right lever 1a, and the operation left lever 1b may be collectively referred to as operation levers 1 and 23.

The upper rotating body 12 is equipped with an engine 18 as a prime mover, hydraulic pumps 2a and 2b, a pilot pump 48, and the like. The hydraulic pumps 2 a and 2 b and the pilot pump 48 are driven by the engine 18. The hydraulic pumps 2a and 2b are variable displacement pumps whose capacity is controlled by regulators 2aa and 2ba, and the pilot pump 48 is a fixed displacement pump. The hydraulic pump 2 and the pilot pump 48 suck and discharge hydraulic oil from the tank 200. In the present embodiment, as shown in FIG. 2, a shuttle block 162 is provided in the middle of the pilot lines 144, 145, 146, 147, 148, 149. The hydraulic signals output from the operating devices 45, 46, 47 are also input to the regulators 2aa, 2ba via the shuttle block 162. Although a detailed configuration of the shuttle block 162 is omitted, a hydraulic signal is input to the regulators 2aa and 2ba via the shuttle block 162, and the discharge flow rates of the hydraulic pumps 2a and 2b are controlled according to the hydraulic signal.

The pump line 48a, which is the discharge pipe of the pilot pump 48, passes through the lock valve 39, is branched into a plurality of parts, and is connected to each of the operating devices 45, 46, 47 and each valve in the front control hydraulic unit 160. The lock valve 39 is an electromagnetic switching valve in this embodiment, and its electromagnetic drive unit is electrically connected to a position detector of a gate lock lever (not shown) arranged in the cab (FIG. 1). The position of the gate lock lever is detected by a position detector, and a signal corresponding to the position of the gate lock lever is input to the lock valve 39 from the position detector. If the position of the gate lock lever is at the lock position, the lock valve 39 is closed and the pump line 48a is shut off, and if it is at the unlock position, the lock valve 39 is opened and the pump line 48a is opened. That is, when the pump line 48a is shut off, the operations by the operation devices 45, 46, and 47 are invalidated, and operations such as turning and excavation are prohibited.

The operation devices 45, 46, and 47 are hydraulic pilot type operation devices that instruct the operation of a plurality of hydraulic actuators according to the operation of the operator. The operation devices 45, 46, and 47 reduce the pressure oil discharged from the pilot pump 48, and operate the pilots according to the operation amounts (for example, lever strokes) and operation directions of the operation levers 1 and 23 respectively operated by the operator. Pressure (sometimes referred to as operating pressure). The pilot pressure thus generated is supplied to the hydraulic drive units 150a to 155b of the corresponding flow control valves 15a to 15f (FIG. 2 or FIG. 3) via the pilot lines 144a to 149b (see FIG. 3). It is used as a control signal for driving the control valves 15a to 15f.

The hydraulic oil (hydraulic oil) discharged from the hydraulic pump 2 travels through the flow control valves 15a, 15b, 15c, 15d, 15e, and 15f (see FIG. 2) to travel right hydraulic motor 3a, travel left hydraulic motor 3b, and turn. The hydraulic motor 4, boom cylinder 5, arm cylinder 6, and bucket cylinder 7 are supplied to drive them. When the boom cylinder 5, the arm cylinder 6, and the bucket cylinder 7 expand and contract by the supplied pressure oil, the boom 8, the arm 9, and the bucket 10 rotate, respectively, and the front work device 1A is driven. Further, the turning hydraulic motor 4 is rotated by the supplied pressure oil, so that the upper turning body 12 turns leftward or rightward with respect to the lower running body 11. Then, the traveling right hydraulic motor 3a and the traveling left hydraulic motor 3b are rotated by the supplied pressure oil, so that the lower traveling body 11 travels.

エ ン ジ ン An engine speed detector 490, which is a rotation sensor for detecting the engine speed, is mounted around the output shaft of the engine 18.

FIG. 4 is a configuration diagram of a machine control (MC) system provided in the excavator according to the present embodiment. The system shown in FIG. 4 executes a process of controlling the front working device 1A based on a predetermined condition when the operating devices 45 and 46 are operated by the operator as the MC. In this paper, the machine control (MC) is compared with “automatic control” in which the operation of the working device 1A is controlled by a computer when the operating devices 45 and 46 are not operated, whereas the operation of the working device 1A is performed only when the operating devices 45 and 46 are operated. May be referred to as “semi-automatic control” that is controlled by a computer. Next, details of the MC in the present embodiment will be described.

As the MC of the front working device 1A, when a digging operation (specifically, at least one instruction of an arm cloud, a bucket cloud, and a bucket dump) is input via the operation devices 45b and 46a, the target surface 60 (FIG. 5) and the tip of the working device 1A (in this embodiment, the toe of the bucket 10), the position of the tip of the working device 1A is held on the target surface 60 and in an area above the target surface 60. As described above, the control signal for forcibly operating at least one of the hydraulic actuators 5, 6, 7 (for example, the boom cylinder 5 is extended to forcibly perform the boom raising operation) is transmitted to the corresponding flow control valve 15a, 15b, 15c.

(4) Since the MC prevents the toe of the bucket 10 from intruding below the target surface 60, excavation along the target surface 60 is possible regardless of the skill level of the operator. In the present embodiment, the control point of the front working device 1A at the time of MC is set to the tip of the bucket 10 of the hydraulic shovel (the tip of the working device 1A), but the control point is a point on the working device 1A. If so, it can be changed to something other than the bucket toe. For example, the bottom of the bucket 10 and the outermost part of the bucket link 13 can be selected.

The system shown in FIG. 4 is a display device that is installed in the operator's cab and is capable of displaying the positional relationship between the target surface 60 and the working device 1A, the working device attitude detecting device 50, the target surface setting device 51, the operator operation detecting device 52a. (For example, a liquid crystal display) 53, a control selection switch (control selection device) 97 for selecting either permission or prohibition (ON and OFF) of bucket angle control (also referred to as work implement angle control) by MC, Work of the hydraulic excavator 1 and the target angle setting device 96 for setting the angle (target angle) of the bucket 10 with respect to the target surface 60 in the bucket angle control by the MC, the engine speed detecting device 490 for detecting the engine speed, and the like. For selecting one of the normal mode (first mode) and the economy mode (second mode) as the mode A mode selection device (mode selection switch) 98 and an engine speed dial which is a target engine speed setting device for adjusting a target engine speed of the engine 18 by setting a desired value as a target value of the engine speed. (Rotational number dial) 99 and a controller (control device) 40 which is a computer for controlling the MC.

The working device posture detecting device 50 includes a boom angle sensor 30, an arm angle sensor 31, a bucket angle sensor 32, and a vehicle body tilt angle sensor 33. These angle sensors 30, 31, 32, and 33 function as posture sensors of the working device 1A.

The target plane setting device 51 is an interface capable of inputting information on the target plane 60 (including position information and inclination angle information of each target plane). The target plane setting device 51 is connected to an external terminal (not shown) that stores three-dimensional data of a target plane defined on a global coordinate system (absolute coordinate system). The input of the target plane via the target plane setting device 51 may be manually performed by the operator.

The operator operation detection device 52a includes a pressure sensor 70a that obtains an operation pressure (first control signal) generated in the pilot lines 144, 145, and 146 by an operation of the operation levers 1a, 1b ( operation devices 45a, 45b, 46a) by the operator. 70b, 71a, 71b, 72a, and 72b. That is, the operation on the hydraulic cylinders 5, 6, 7 according to the working device 1A is detected.

The mode selection device 98 sets a first upper limit Ru1, which is the upper limit of the engine speed during normal operation, as a plurality of work modes predetermined by the upper limit of the engine speed during excavation work. Mode selection for selecting one of the (first mode) and the economy-oriented MC mode (second mode) in which the second upper limit Ru2 which is an upper limit smaller than the first upper limit Ru1 is set. Switch. In addition to these work modes, a power MC mode in which a work amount is emphasized, in which a third upper limit Ru3 which is an upper limit larger than the first upper limit Ru1, may be selected.

<Front control hydraulic unit 160>
As shown in FIG. 3, the front control hydraulic unit 160 is provided on the pilot lines 144a and 144b of the operating device 45a for the boom 8, and detects a pilot pressure (first control signal) as an operation amount of the operation lever 1a. Pressure sensors 70a and 70b, an electromagnetic proportional valve 54a whose primary port side is connected to a pilot pump 48 via a pump line 48a to reduce and output a pilot pressure from the pilot pump 48, and a pilot of an operating device 45a for the boom 8 The line 144a is connected to the secondary port of the electromagnetic proportional valve 54a, and selects the high pressure side of the pilot pressure in the pilot line 144a and the control pressure (second control signal) output from the electromagnetic proportional valve 54a. A shuttle valve 82a for guiding the hydraulic drive unit 150a to the hydraulic drive unit 15a and an operating device 45a for the boom 8; B is installed in the lot line 144b, and a solenoid proportional valve 54b to reduce and output the pilot pressure of the control signal in the pilot line 144b based on (first control signal) from the controller 40.

Further, the front control hydraulic unit 160 is provided on the pilot lines 145a and 145b for the arm 9, and detects a pilot pressure (first control signal) as an operation amount of the operation lever 1b and outputs the pressure sensor 71a to the controller 40. , 71b, an electromagnetic proportional valve 55b installed in a pilot line 145b, and reducing and outputting a pilot pressure (first control signal) based on a control signal from the controller 40, and an electromagnetic proportional valve 55b installed in a pilot line 145a. Is provided with an electromagnetic proportional valve 55a that reduces the pilot pressure (first control signal) in the pilot line 145a based on the control signal described above.

Further, the front control hydraulic unit 160 includes a pilot line 146a, 146b for the bucket 10, a pressure sensor 72a that detects a pilot pressure (first control signal) as an operation amount of the operation lever 1a and outputs the pilot pressure to the controller 40. 72 b, electromagnetic proportional valves 56 a and 56 b for reducing and outputting a pilot pressure (first control signal) based on a control signal from the controller 40, and a pilot pressure from the pilot pump 48 which is connected to the pilot pump 48 on the primary port side. Valves 56c and 56d for reducing the pressure and outputting, and the pilot pressure in the pilot lines 146a and 146b and the high pressure side of the control pressure output from the proportional valves 56c and 56d are selected to hydraulically drive the flow control valve 15c. Shuttle valves 83a and 83b leading to the sections 152a and 152b are provided respectively. To have. In FIG. 3, connection lines between the pressure sensors 70, 71, 72 and the controller 40 are omitted.

The opening of the electromagnetic proportional valves 54b, 55a, 55b, 56a, 56b is maximum when power is not supplied, and the opening decreases as the current as a control signal from the controller 40 increases. On the other hand, the electromagnetic proportional valves 54a, 56c, 56d have an opening of zero when not energized and have an opening when energized, and the opening increases as the current (control signal) from the controller 40 increases. As described above, the opening degrees 54, 55, 56 of the respective solenoid proportional valves are in accordance with the control signal from the controller 40.
In the control hydraulic unit 160 configured as described above, when a control signal is output from the controller 40 to drive the electromagnetic proportional valves 54a, 56c, 56d, even when there is no operator operation of the corresponding operating devices 45a, 46a, Since the pilot pressure (second control signal) can be generated, the boom raising operation, the bucket cloud operation, and the bucket dump operation can be forcibly generated. Similarly, when the controller 40 drives the proportional solenoid valves 54b, 55a, 55b, 56a, 56b, the pilot pressure (first control signal) generated by the operator operation of the operation devices 45a, 45b, 46a is reduced. A pressure (second control signal) can be generated, and the speed of the boom lowering operation, the arm cloud / dump operation, and the bucket cloud / dump operation can be forcibly reduced from the value of the operator operation.

In this document, among the control signals for the flow control valves 15a to 15c, the pilot pressure generated by operating the operation devices 45a, 45b, 46a is referred to as a "first control signal". Then, among the control signals for the flow rate control valves 15a to 15c, the controller 40 drives the electromagnetic proportional valves 54b, 55a, 55b, 56a, 56b to correct (reduce) the first control signal, and generates a pilot pressure; The pilot pressure newly generated separately from the first control signal by driving the electromagnetic proportional valves 54a, 56c, 56d by the controller 40 is referred to as a "second control signal".

The second control signal is generated when the speed vector of the control point of the working device 1A generated by the first control signal violates a predetermined condition, and the speed vector of the control point of the working device 1A according to the predetermined condition is generated. Is generated as a control signal. When the first control signal is generated for one hydraulic drive unit and the second control signal is generated for the other hydraulic drive unit in the same flow control valves 15a to 15c, the second control signal is given priority. The first control signal is cut off by an electromagnetic proportional valve, and the second control signal is input to the other hydraulic drive unit. Therefore, among the flow control valves 15a to 15c, those for which the second control signal is calculated are controlled based on the second control signal, and those for which the second control signal is not calculated are based on the first control signal. Those that are controlled and for which neither the first nor the second control signal is generated are not controlled (driven). When the first control signal and the second control signal are defined as described above, MC can be said to be control of the flow control valves 15a to 15c based on the second control signal.

<Controller 40>
4, the controller 40 includes an input unit 91, a central processing unit (CPU) 92 as a processor, a read-only memory (ROM) 93 and a random access memory (RAM) 94 as storage units, and an output unit 95. Have. The input unit 91 receives signals from the angle sensors 30 to 32 and the inclination angle sensor 33 that are the working device attitude detection devices 50, signals from the target surface setting device 51 that is a device for setting the target surface 60, A signal from an operator operation detection device 52a, which is an operation amount sensor (including pressure sensors 70, 71, 72) for detecting an operation amount from the devices 45a, 45b, 46a, and a switching position of the control selection switch 97 (permission / prohibition) ), A signal indicating the target angle from the target angle setting device 96, a signal from the engine speed detection device 490, and a signal indicating the work mode (normal / economy) selected by the mode selection device 98. The CPU 92 inputs a signal indicating the target engine speed set by the engine speed dial 99 and converts the signal so that the CPU 92 can calculate. The ROM 93 is a storage device that stores a control program for executing an MC including a process related to a flowchart described later, and various information necessary for executing the flowchart, and the CPU 92 executes a control program stored in the ROM 93. The predetermined arithmetic processing is performed on the signals fetched from the input unit 91 and the memories 93 and 94 according to the following. The output unit 95 drives and controls the hydraulic actuators 5 to 7 by generating output signals corresponding to the calculation results of the CPU 92 and outputting the signals to the electromagnetic proportional valves 54 to 56 or the display device 53. Alternatively, images of the vehicle body 1B, the bucket 10, the target surface 60, and the like are displayed on the screen of the display device 53.

Although the controller 40 in FIG. 4 includes semiconductor memories such as a ROM 93 and a RAM 94 as storage devices, any storage device can be used in particular. For example, a semiconductor memory such as an SSD (Solid State Drive) or an HHD ( A magnetic storage device such as a Hard Disc Drive is applicable.

FIG. 6 is a functional block diagram of the controller 40. The controller 40 includes an MC control unit 43, an electromagnetic proportional valve control unit 44, a display control unit 374, and an engine speed control unit 49.

-Display control unit 374-
The display control unit 374 is a part that controls the display device 53 based on the working device attitude and the target plane output from the MC control unit 43. The display control unit 374 is provided with a display ROM in which a large number of display-related data including images and icons of the working device 1A are stored, and the display control unit 374 determines a predetermined value based on a flag included in the input information. The program is read and the display on the display device 53 is controlled.

-MC controller 43-
FIG. 7 is a functional block diagram of the MC control unit 43 in FIG. The MC control unit 43 includes an operation amount calculation unit 43a, a posture calculation unit 43b, a target plane calculation unit 43c, a cylinder speed correlation data storage unit 43d, a cylinder speed correlation data calculation unit 43e, a boom control unit 81a, A bucket control unit 81b.

The operation amount calculation unit 43a calculates the operation amount of the operation devices 45a, 45b, 46a (operation levers 1a, 1b) based on the input from the operator operation detection device 52a. In the present embodiment, the operation amounts of the operation devices 45a, 45b, 46a can be calculated from the detection values of the pressure sensors 70, 71, 72, which are the operator operation detection devices 52a.

The calculation of the operation amount by the pressure sensors 70, 71, 72 is only an example. For example, a position sensor (for example, a rotary encoder) that detects the rotational displacement of the operation lever of each of the operation devices 45a, 45b, 46a uses the operation lever. May be detected.

Based on information from the angle sensors 30 to 32 and the inclination angle sensor 33 that are the working device posture detecting devices 50, the posture calculating unit 43b controls the front working device 1A in the shovel coordinate system (local coordinate system) set for the hydraulic shovel 1. The posture and the position of the toe of the bucket 10 are calculated.

The attitude of the front working device 1A can be defined on the shovel coordinate system (local coordinate system) in FIG. The shovel coordinate system (XZ coordinate system) shown in FIG. 5 is a coordinate system set on the upper revolving superstructure 12, and for example, the center point of the center axis of the boom pin that rotatably supports the boom 8 on the upper revolving superstructure 12 is set as the origin. The Z axis is set in the vertical direction (upward) and the X axis in the horizontal direction (forward) of the upper revolving unit 12. The angle of inclination of the boom 8 with respect to the X axis is the boom angle α, the angle of inclination of the arm 9 with respect to the boom 8 is the arm angle β, and the angle of inclination of the bucket toe with respect to the arm is the bucket angle γ. The inclination angle of the vehicle body 1B (the upper revolving unit 12) with respect to the horizontal plane (reference plane) is defined as the inclination angle θ. The boom angle α is detected by the boom angle sensor 30, the arm angle β is detected by the arm angle sensor 31, the bucket angle γ is detected by the bucket angle sensor 32, and the tilt angle θ is detected by the vehicle body tilt angle sensor 33. Assuming that the lengths of the boom 8, the arm 9, and the bucket 10 are L1, L2, and L3, respectively, as defined in FIG. 5, the coordinates of the bucket toe position in the shovel coordinate system and the attitude of the working device 1A are L1, L2, and L3. , Α, β, γ.

The target plane calculation unit 43c calculates the position information of the target plane 60 based on the information from the target plane setting device 51, and stores this in the ROM 93. In the present embodiment, as shown in FIG. 5, a cross-sectional shape obtained by cutting the three-dimensional target plane data on the plane on which the work apparatus 1A moves (operating plane of the work machine) is defined as a target plane 60 (two-dimensional target plane). Use.

In the example of FIG. 5, there is one target plane 60, but there may be a plurality of target planes. When there are a plurality of target planes, for example, a method of setting the one closest to the working device 1A as the target plane, a method of setting the one located below the bucket toe as the target plane, or a method arbitrarily selected is used. There are methods to set the target plane.

The cylinder speed correlation data storage unit 43d is a storage area provided in a storage device (for example, the ROM 93) in the controller 40. For each of the hydraulic cylinders (each hydraulic actuator) 5, 6, 7, the operating devices 45a, 45b, Correlation data indicating the relationship between the operation amount 46a and the cylinder speed is stored. Three types of correlation data are stored according to the number of hydraulic cylinders 5, 6, and 7, and when executing MC, the speed of hydraulic cylinders 5, 6, 7 corresponding to the operation of operating devices 45a, 45b, 46a is determined. Used when performing calculations. The correlation data of each of the hydraulic cylinders 5, 6, and 7 has a plurality of different graphs according to the range of the rotation speed of the engine 18. In the example of FIG. 9, there are three graphs in which the range of the engine speed is divided into three, large, medium, and small. The graph used for calculating the cylinder speed is changed according to the range to which the rotation speed belongs. These correlation data are set in advance as a table of cylinder speeds with respect to operation amounts obtained by experiments and simulations, and are set so that the cylinder speed increases as the engine speed increases when compared with the same operation amount. . Note that the graph shape (broken line shape) in the correlation data of FIG. 9 is merely an example, and for example, a curve may be used. Further, it is not necessary to classify the engine speed into three as shown in FIG. 9, and the engine speed may be classified into, for example, two or four or more as long as it matches the actual situation.

The cylinder speed correlation data calculation unit 43e, based on the operation amount information of the operation devices 45a, 45b, 46a and the correlation data stored in the cylinder speed correlation data storage unit 43d when operating the operation devices 45a, 45b, 46a. , Calculating the correlation data of the hydraulic actuators 5, 6, 7 corresponding to the operation of the operating devices 45a, 45b, 46a among the plurality of hydraulic actuators 5, 6, 7; It is characterized in that the graph used for each correlation data is changed according to the actual rotation speed of the engine 18 detected by the engine 490.

The cylinder speed correlation data calculation unit 43e first selects the correlation data of the hydraulic actuators 5, 6, 7 corresponding to the operation of the operating devices 45a, 45b, 46a from among the plurality of correlation data, and then selects the correlation data. A graph corresponding to the actual rotation speed of the engine 18 is selected. For example, in the example of FIG. 9, a graph in which the actual engine speed Rr is “small” is selected when the engine speed belongs to a range of 0 or more and less than the first engine speed R1 (0 ≦ Rr <R1), The “middle” graph is selected when it belongs to the range (R1 ≦ Rr <R2) equal to or more than the first rotation speed R1 and less than the second rotation speed R2, and the “large” graph is equal to or more than the second rotation speed R2 and maximum rotation speed. It is selected when it belongs to the range of less than or equal to several Rmax (R2 ≦ Rr ≦ Rmax). As described above, the cylinder speed correlation data calculation unit 43e calculates the corresponding engine speed from the correlation data stored in the cylinder speed correlation data storage unit 43d according to the actual rotation speed detected by the engine speed detection device 490. The correlation data is selected and output to the actuator control unit 81.

The boom control unit 81a and the bucket control unit 81b constitute an actuator control unit 81 that controls at least one of the plurality of hydraulic actuators 5, 6, 7 according to predetermined conditions when operating the operation devices 45a, 45b, 46a. . The actuator control section 81 calculates the target pilot pressure of the flow control valves 15a, 15b, 15c of the hydraulic cylinders 5, 6, 7 and outputs the calculated target pilot pressure to the electromagnetic proportional valve control section 44.

When operating the operation devices 45a, 45b, and 46a, the boom control unit 81a determines the position of the target surface 60, the attitude of the front working device 1A and the position of the toe of the bucket 10, the operation amounts of the operation devices 45a, 45b, and 46a. Is a part for executing the MC for controlling the operation of the boom cylinder 5 (boom 8) so that the toe (control point) of the bucket 10 is located on or above the target surface 60. The boom control unit 81a calculates a target pilot pressure of the flow control valve 15a of the boom cylinder 5. Details of the MC by the boom control unit 81a will be described later with reference to FIG.

The bucket control unit 81b is a part for executing bucket angle control by the MC when operating the operation devices 45a, 45b, 46a. Specifically, when the distance between the target surface 60 and the toe of the bucket 10 is equal to or less than a predetermined value, the angle θ of the bucket 10 with respect to the target surface 60 becomes the target surface bucket angle θTGT set by the target angle setting device 96 in advance. Then, an MC (bucket angle control) for controlling the operation of the bucket cylinder 7 (bucket 10) is executed. The bucket controller 81b calculates a target pilot pressure of the flow control valve 15c of the bucket cylinder 7.

-Electromagnetic proportional valve control unit 44-
The electromagnetic proportional valve control unit 44 calculates a command to each of the electromagnetic proportional valves 54 to 56 based on the target pilot pressure output from the actuator control unit 81 to each of the flow control valves 15a, 15b, 15c. If the pilot pressure (first control signal) based on the operator's operation matches the target pilot pressure calculated by the actuator control unit 81, the current value (command value) to the corresponding electromagnetic proportional valves 54 to 56 Becomes zero, and the operation of the corresponding electromagnetic proportional valves 54 to 56 is not performed.

-Engine speed control unit 49-
The engine speed control unit 49 is based on the target engine speed set by the engine speed dial 99 and the upper limit value (target engine speed) of the engine speed specified by the work mode selected by the mode selection device 98. , Generates and outputs a control signal to the engine 18, and executes processing for controlling the number of revolutions of the engine 18. When the target rotation speed set by the engine rotation speed dial 99 exceeds the upper limit value of the engine rotation speed specified by the work mode selected by the mode selection device 98, the engine rotation speed control unit 49 sets the upper limit value to the target rotation speed. It is configured to control the engine 18 as a number. The engine speed control unit 49 is also called an engine control unit, and may be configured as a controller independent of the controller 40.

<Flow of boom raising control by boom control unit 81a>
The controller 40 of the present embodiment executes the boom raising control by the boom control unit 81a as MC. FIG. 8 shows a flow of the boom raising control by the boom control unit 81a. FIG. 8 is a flowchart of the MC executed by the boom control unit 81a, and the processing is started when the operation device 45b is operated by the operator.

In S410, the boom control unit 81a determines the operation amount calculated by the operation amount calculation unit 43a and the cylinder speed correlation data calculation unit 43e for the hydraulic cylinders 5, 6, and 7 (for example, the arm cylinder 6) for which the operation amounts are calculated. The operation speeds (cylinder speeds) of the hydraulic cylinders 5, 6, and 7 corresponding to the operation of the operating device are calculated based on the correlation data input from. Note that, as the correlation data input from the cylinder speed correlation data calculation unit 43e, correlation data regarding a hydraulic cylinder (for example, the arm cylinder 6) corresponding to the operation of the operating device is input. A graph corresponding to the actual engine speed detected by the engine speed detector 490 is selected.

In S420, the boom control unit 81a calculates the bucket tip by an operator operation based on the operation speeds of the hydraulic cylinders 5, 6, and 7 calculated in S410 and the posture of the working device 1A calculated in the posture calculation unit 43b. A (toe) speed vector B is calculated.

In S430, the boom control unit 81a determines the target surface of the control target from the bucket tip from the position (coordinates) of the toe of the bucket 10 calculated by the posture calculation unit 43b and the distance of the straight line including the target surface 60 stored in the ROM 93. A distance D (see FIG. 5) up to 60 is calculated. Then, based on the distance D and the graph of FIG. 10, the limit value ay of the component of the velocity vector at the tip of the bucket perpendicular to the target plane 60 is calculated. Note that the limit value ay is the lower limit value of the component of the speed vector at the tip of the bucket perpendicular to the target plane 60. If the vertical component of the speed vector B is smaller than the limit value ay, the speed vector at the tip of the bucket is The component is corrected so as to be held at the limit value ay.

In S440, the boom control unit 81a acquires a component by perpendicular to the target plane 60 in the speed vector B at the tip of the bucket calculated by the operator in S420.

In S450, the boom control unit 81a determines whether the limit value ay calculated in S430 is 0 or more. The xy coordinates are set as shown in the upper right of FIG. In the xy coordinates, the x axis is parallel to the target plane 60 and the right direction in the figure is positive, and the y axis is perpendicular to the target plane 60 and upward in the figure is positive. In the legend in FIG. 8, the vertical component by and the limit value ay are negative, and the horizontal component bx, the horizontal component cx, and the vertical component cy are positive. As is apparent from FIG. 10, when the limit value ay is 0, the distance D is 0, that is, when the toe is located on the target surface 60. When the limit value ay is positive, the distance D is negative. That is, the toe is located below the target surface 60, and when the limit value ay is negative, the distance D is positive, that is, the toe is located above the target surface 60. If the limit value ay is determined to be 0 or more in S450 (that is, if the toe is located on or below the target surface 60), the process proceeds to S460, and if the limit value ay is less than 0, the process proceeds to S480.
In S460, the boom control unit 81a determines whether or not the vertical component by of the toe speed vector B by the operator's operation is 0 or more. When by is positive, it indicates that the vertical component by of the velocity vector B is upward, and when by is negative, it indicates that the vertical component by of the velocity vector B is downward. If it is determined in step S460 that the vertical component by is equal to or greater than 0 (that is, if the vertical component by is upward), the process proceeds to step S470. If the vertical component by is less than 0, the process proceeds to step S500.
In S470, the boom control unit 81a compares the limit value ay with the absolute value of the vertical component by. If the absolute value of the limit value ay is equal to or greater than the absolute value of the vertical component by, the process proceeds to S500. On the other hand, if the absolute value of the limit value ay is less than the absolute value of the vertical component by, the process proceeds to S530.

In S500, the boom control unit 81a selects "cy = ay-by" as an equation for calculating a component cy of the speed vector C at the tip of the bucket to be generated by the operation of the boom 8 under machine control, which is perpendicular to the target plane 60. The vertical component cy is calculated based on the equation, the limit value ay in S430, and the vertical component by in S440. Then, a velocity vector C capable of outputting the calculated vertical component cy is calculated, and its horizontal component is set as cx (S510).

In S520, the target speed vector T is calculated. Assuming that a component perpendicular to the target plane 60 of the target speed vector T is ty and a horizontal component tx, they can be expressed as “ty = by + cy, tx = bx + cx”, respectively. Substituting the expression (cy = ay−by) of S500 into this, the target speed vector T is eventually “ty = ay, tx = bx + cx”. That is, the vertical component ty of the target speed vector when S520 is reached is limited to the limit value ay, and the forced boom raising by machine control is activated.

In S480, the boom control unit 81a determines whether the vertical component by of the toe speed vector B by the operator's operation is 0 or more. If the vertical component by is determined to be 0 or more in S480 (that is, if the vertical component by is upward), the process proceeds to S530. If the vertical component by is less than 0, the process proceeds to S490.

In S490, the boom control unit 81ad compares the limit value ay with the absolute value of the vertical component by, and proceeds to S530 if the absolute value of the limit value ay is equal to or greater than the absolute value of the vertical component by. On the other hand, if the absolute value of the limit value ay is less than the absolute value of the vertical component by, the process proceeds to S500.

If it reaches S530, there is no need to operate the boom 8 by machine control, so the boom control unit 81a sets the speed vector C to zero. In this case, the target speed vector T becomes “ty = by, tx = bx” based on the equation (ty = by + cy, tx = bx + cx) used in S520, and matches the speed vector B by the operator operation (S540).

In S550, the boom control unit 81a calculates the target speed of each of the hydraulic cylinders 5, 6, 7 based on the target speed vector T (ty, tx) determined in S520 or S540. As is apparent from the above description, when the target speed vector T does not coincide with the speed vector B in FIG. 8, the speed vector C generated by the operation of the boom 8 by the machine control is added to the speed vector B. A speed vector T is realized.

In S560, the boom control unit 81a determines the target speed of each of the hydraulic cylinders 5, 6, 7 (for example, the boom cylinder 5 and the arm cylinder 6) calculated in S550, and the hydraulic cylinders 5, 6 for which the target speed has been calculated. , 7 on the basis of the correlation data input from the cylinder speed correlation data calculation unit 43e, and the operation of the operating devices 45a, 45b, 46a required to output the target speeds calculated by the hydraulic cylinders 5, 6, 7 respectively. The amount, that is, the target pilot pressure to the flow control valves 15a, 15b, 15c of the hydraulic cylinders 5, 6, 7 is calculated. In addition, as the correlation data input from the cylinder speed correlation data calculation unit 43e, correlation data regarding the hydraulic cylinders 5, 6, and 7 for which the target speed has been calculated in S550 is input, and the correlation data is the same as in S410. A graph corresponding to the actual engine speed detected by the engine speed detector 490 is selected. In the present embodiment, the correlation data input from the cylinder speed correlation data calculator 43e is used when converting the cylinder speed to the target pilot pressure, mainly from the viewpoint of saving the storage capacity of the storage device in the controller 40. However, the use of the correlation data is only one of the methods of calculating the target pilot pressure, and the target pilot pressure may be calculated by another method.

In S590, the boom control unit 81a outputs the target pilot pressure to the flow control valves 15a, 15b, 15c of each of the hydraulic cylinders 5, 6, 7 to the electromagnetic proportional valve control unit 44.

The electromagnetic proportional valve control unit 44 controls the electromagnetic proportional valves 54, 55, and 56 so that the target pilot pressure acts on the flow control valves 15a, 15b, and 15c of the hydraulic cylinders 5, 6, and 7, thereby controlling the working device. Excavation by 1A is performed. For example, when the operator operates the operation device 45b to perform horizontal excavation by arm cloud operation, the electromagnetic proportional valve 55c is controlled so that the tip of the bucket 10 does not enter the target surface 60, and the boom 8 is raised. Is done automatically.

<Operation / effect>
In the hydraulic shovel configured as described above, even if the actual rotational speed of the engine 18 fluctuates due to the operator adjusting the engine target rotational speed using the engine rotational speed dial 99, the controller 40 is controlled. The (cylinder speed correlation data calculation unit 43e) selects correlation data between the operation amount and the cylinder speed suitable for the changed actual rotation speed. Then, since the MC by the controller 40 (actuator control unit 81) is executed based on the cylinder speed close to the actual speed obtained from the correlation data, the excavation accuracy of the MC can be suppressed from lowering than before. That is, the accuracy of MC can be stabilized regardless of the engine speed.

<Modification>
In the above embodiment, the actual engine speed of the engine 18 is detected by the engine speed detector 490, and the correlation data corresponding to the actual engine speed is calculated by the cylinder speed correlation data calculation unit 43e to obtain the actuator control unit 81 (boom). Although the configuration for outputting to the control unit 81a) has been described, the target rotation is output from the engine speed dial 99 to the cylinder speed correlation data calculation unit 43e, and the correlation data according to the target rotation speed is calculated. A configuration in which the calculation is performed by the unit 43e and output to the actuator control unit 81 (boom control unit 81a) may be employed. When the correlation data is selected based on the target rotation speed in this manner, the change of the correlation data (line graph) is suppressed more frequently than when the correlation data is selected based on the actual rotation speed. A stable improvement in MC accuracy can be expected. FIG. 14 shows a functional block diagram of the MC control unit 43 in this case.

<Second embodiment>
Next, a second embodiment will be described with reference to FIG. FIG. 11 is a functional block diagram of the MC control unit 43 according to the second embodiment. The same parts as those in the previous figures are denoted by the same reference numerals, and the description may be appropriately omitted.

As shown in FIG. 11, the MC control unit 43 of the present embodiment includes an engine speed upper limit value calculation unit 43f. The engine rotation speed upper limit calculation unit 43f determines the upper limit (first upper limit Ru1 or second upper limit Ru2) of the engine rotation speed in accordance with the work mode (normal MC mode or economy MC mode) set by the mode selection device 98. (Where Ru1> Ru2) is calculated, and the upper limit value is output to the engine speed control unit 49. The engine speed control unit 49 controls the engine speed so as not to exceed the input upper limit. Since this control is performed prior to the target speed input from the engine speed dial 99, when the upper limit value is smaller than the target speed input from the engine speed dial 99, the engine speed is controlled to the upper limit value. You.

In the mode selection device 98, as described above, the operator can select the economy MC mode in which the upper limit Ru2 of the engine speed is lower than the upper limit Ru1 of the engine speed when the normal MC is performed.

<Operation / effect>
In the hydraulic excavator configured as described above, the operator selects the economy MC mode in which the upper limit value Ru2 of the engine speed is set lower than the normal MC mode by using the mode selection device 98, so that the actual operation of the engine 18 is performed. Even when the rotation speed fluctuates, the controller 40 (cylinder speed correlation data calculation unit 43e) selects correlation data of the operation amount and the cylinder speed suitable for the fluctuated actual rotation speed. Since the MC by the controller 40 (actuator control unit 81) is executed based on the cylinder speed close to the actual speed obtained from the correlation data, the excavation accuracy of the MC decreases even if the work mode is changed. Can be suppressed. Further, since the upper limit of the engine speed is lower than that in the normal MC mode, fuel efficiency can be improved.

<Modification>
In the above embodiment, the actual engine speed of the engine 18 is detected by the engine speed detector 490, and the correlation data corresponding to the actual engine speed is calculated by the cylinder speed correlation data calculation unit 43e to obtain the actuator control unit 81 (boom). Although the configuration for outputting to the control unit 81a) has been described, the target rotation speed (upper limit value of the engine rotation speed) is output from the engine rotation speed upper limit calculation unit 43f to the cylinder speed correlation data calculation unit 43e, and the target rotation speed is output. A configuration may be adopted in which correlation data corresponding to the above is calculated by the cylinder speed correlation data calculation unit 43e and output to the actuator control unit 81 (boom control unit 81a). When the correlation data is selected based on the target rotation speed in this manner, the change of the correlation data (line graph) is suppressed more frequently than when the correlation data is selected based on the actual rotation speed. A stable improvement in MC accuracy can be expected. FIG. 15 shows a functional block diagram of the MC control unit 43 in this case.

<Third embodiment>
In the first and second embodiments, a plurality of correlation data tables are stored in the cylinder speed correlation data storage unit 43d in order to calculate cylinder speed correlation data corresponding to the engine speed. The table corresponding to the engine speed was selected from among them. However, only the correlation data at the representative engine speed (for example, the rated speed) is stored in the cylinder speed correlation data storage unit 43d, and a correction coefficient according to the engine speed is calculated to calculate the cylinder speed correlation data. A configuration may be adopted in which the correlation data is corrected by adding or multiplying the correction coefficient to the correlation data by the section 43e, and the corrected correlation data is output to the actuator control section 81. This embodiment is referred to as a third embodiment and will be described with reference to FIGS.

FIG. 12 is a functional block diagram of the MC control unit 43 according to the third embodiment. The same parts as those in the previous figures are denoted by the same reference numerals, and the description may be appropriately omitted.

The MC control unit 43 shown in FIG. 12 includes a correction coefficient calculation unit 43g, a cylinder speed correlation data storage unit 43d, and a cylinder speed correlation data calculation unit 43e.

The correction coefficient calculation unit 43g is a part that executes a process of calculating a correction coefficient based on the actual rotation speed input from the engine speed detection device 490. FIG. 13 shows a table that defines the relationship between the engine speed and the correction coefficient. According to this table, the correction coefficient calculation unit 43g outputs 1 as the correction coefficient k when the engine speed is at the rated speed, and when the engine speed is less than the rated speed, it is monotonous as the engine speed decreases. (That is, the correction coefficient k is greater than 0 and less than 1). The correction coefficient k is output to the cylinder speed correlation data calculation unit 43e.

The cylinder speed correlation data storage unit 43d stores the relationship between the operation amounts of the operating devices 45a, 45b, and 46a and the cylinder speed when the engine speed is the rated speed for each of the hydraulic cylinders (each hydraulic actuator) 5, 6, and 7. Is stored.

When operating the operating devices 45a, 45b, 46a, the cylinder speed correlation data calculating unit 43e calculates the operation amount information of the operating devices 45a, 45b, 46a, the correlation data stored in the cylinder speed correlation data storage unit 43d, and the correction coefficient. Based on the correction coefficient k calculated by the calculation unit 43g, correlation data of the hydraulic actuators 5, 6, 7 corresponding to the operation of the operating devices 45a, 45b, 46a among the plurality of hydraulic actuators 5, 6, 7 is calculated. This is the part that executes processing. The cylinder speed correlation data calculation unit 43e of the present embodiment calculates the actual rotation speed of the engine 18 detected by the engine speed detection device 490 and the correction coefficient k calculated using the table of FIG. The correlation data of the rated rotational speed stored in 43d is multiplied and corrected, and the corrected correlation data is output to the actuator control unit 81.

<Operation / effect>
In the hydraulic excavator configured as described above, if the actual rotation speed of the engine 18 fluctuates due to the operator adjusting the engine target rotation speed using the engine rotation speed dial 99, the controller 40 (correction). The coefficient calculation unit 43g) calculates a correction coefficient k corresponding to the actual rotation speed, and determines the operation amounts of the hydraulic actuators 5, 6, and 7 corresponding to the operation of the operation devices 45a, 45b, and 46a and the rated rotation speed that defines the cylinder speed. Is multiplied by the correction coefficient k to obtain corrected correlation data. Then, since the MC is executed by the controller 40 (actuator control unit 81) based on the cylinder speed close to the actual speed obtained from the corrected correlation data, the excavation of the MC is performed as in the first embodiment. A decrease in accuracy can be suppressed. Furthermore, since the data capacity stored in the cylinder speed correlation data storage unit 43d can be reduced as compared with the first embodiment, the storage capacity of the storage device in the controller 40 can be saved.

<Modification>
Note that, in the present embodiment, similarly to the modified examples of the first and second embodiments, the correlation data may be calculated based on the target rotation speed of the engine 18. That is, the target rotation speed or the upper limit thereof is input from the engine rotation speed dial 99 or the engine rotation speed upper limit calculation unit 43f to the correction coefficient calculation unit 43g, and the correction coefficient k corresponding to the target rotation speed is corrected. , And outputs the result to the cylinder speed correlation data calculation unit 43e. When the correlation data is corrected based on the target rotation speed in this manner, the correlation data (line graph) is prevented from being changed more frequently than when the correlation data is corrected based on the actual rotation speed. A stable improvement in MC accuracy can be expected.

<Others>
It should be noted that the present invention is not limited to the above embodiments, and includes various modifications without departing from the gist thereof. For example, the present invention is not limited to one having all the configurations described in the above embodiment, but also includes one in which a part of the configuration is deleted. Further, a part of the configuration according to one embodiment can be added to or replaced by the configuration according to another embodiment.

In the above-described first and second embodiments, the angle sensor that detects the angle of the boom 8, the arm 9, and the bucket 10 is used. However, the posture information of the shovel may be calculated using a cylinder stroke sensor instead of the angle sensor. . Also, a hydraulic pilot type shovel has been described as an example, but an electric lever type shovel may be configured to control a command current generated from the electric lever. The method of calculating the speed vector of the front work device 1A may be obtained from the angular speed calculated by differentiating the angles of the boom 8 and the bucket 10, instead of the pilot pressure by the operator's operation.

The components of the controller 40 and the functions and execution processes of the components may be partially or wholly realized by hardware (for example, a logic that executes the functions is designed by an integrated circuit). good. Further, the configuration related to the controller 40 may be a program (software) that realizes each function related to the configuration of the controller 40 by being read and executed by an arithmetic processing unit (for example, a CPU). Information relating to the program can be stored in, for example, a semiconductor memory (flash memory, SSD, etc.), a magnetic storage device (hard disk drive, etc.), a recording medium (magnetic disk, optical disk, etc.), and the like.

1A front working device, 8 boom, 9 arm, 10 bucket, 30 boom angle sensor, 31 arm angle sensor, 32 bucket angle sensor, 40 controller (control device), 43 MC controller, 43a: manipulated variable calculator, 43b: posture calculator, 43c: target plane calculator, 43d: cylinder speed correlation data storage unit, 43e: cylinder speed correlation data calculator, 43f: engine speed upper limit value calculator, 43g ... Correction coefficient calculation unit, 44: electromagnetic proportional valve control unit, 45: operating device (boom, arm), 46: operating device (bucket, turning), 49: engine speed control unit, 50: working device attitude detecting device, 51 ... Target plane setting device, 52a ... Operator operation detection device, 53 ... Display device, 54, 55, 56 ... Electromagnetic proportional valve, 81 ... Actuator control unit, 1a ... boom control unit, 81b ... bucket control unit, 96 ... target angle setting device, 98 ... mode selection device 99: engine rotational speed dials, 374 ... display controller, 490 ... engine speed detecting device

Claims (7)

1. Motor and
   A hydraulic pump driven by the prime mover,
   A plurality of hydraulic actuators driven by hydraulic oil discharged from the hydraulic pump;
   A working device driven by the plurality of hydraulic actuators,
   An operation device for instructing the operation of the plurality of hydraulic actuators according to an operation of an operator;
   A storage device that stores correlation data indicating a relationship between a speed of a hydraulic actuator corresponding to an operation of the operating device of the plurality of hydraulic actuators and operation amount information of the operating device;
   When operating the operating device, a speed of a hydraulic actuator corresponding to an operation of the operating device among the plurality of hydraulic actuators is calculated based on the operation amount information of the operating device and the correlation data. A control device for controlling at least one of the plurality of hydraulic actuators according to a predetermined condition,
   The work machine, wherein the control device changes the correlation data based on one of a target rotation speed and an actual rotation speed of the prime mover.
2. The work machine according to claim 1,
   The storage device stores a plurality of the correlation data in accordance with the number of revolutions of the prime mover,
   The controller selects one correlation data from the plurality of correlation data stored in the storage device based on one of a target rotation speed and an actual rotation speed of the prime mover. Work machine.
3. The work machine according to claim 1,
   The work machine, wherein the control device corrects the correlation data stored in the storage device based on one of a target rotation speed and an actual rotation speed of the prime mover.
4. The work machine according to claim 1,
   A rotation speed sensor for detecting an actual rotation speed of the prime mover;
   The work machine according to claim 1, wherein the control device changes the correlation data based on an actual rotation speed of the prime mover detected by the rotation speed sensor.
5. The work machine according to claim 1,
   A rotation speed setting device for setting a target rotation speed of the motor;
   The work machine, wherein the control device changes the correlation data based on a target rotation speed of the prime mover set by the rotation speed setting device.
6. The work machine according to claim 5,
   The work machine according to claim 1, wherein the rotation speed setting device is a rotation speed dial for adjusting a rotation speed of the prime mover.
7. The work machine according to claim 5,
   The rotation speed setting device includes, as a work mode of the work machine, a first mode for setting a first upper limit value that is an upper limit value of a rotation speed of the prime mover during a normal operation, and an upper limit smaller than the first upper limit value. A mode selection device for selecting an arbitrary operation mode from a plurality of operation modes including at least a second mode for setting a second upper limit value,
   The control device controls the rotation speed of the prime mover to be equal to or less than an upper limit value of the rotation speed of the prime mover specified in the mode selected by the mode selection device, and changes the correlation data based on the upper limit value. A working machine characterized by:

Images