JP2000352076A - Work machine control device for construction machinery - Google Patents

Abstract

(57) [Summary] (With correction) [Problem] To appropriately control the operation of a work machine even when a boundary of a limit value is set at a position overlapping an interference avoidance area. SOLUTION: An interference prevention control unit 7c includes a posture calculation unit 7b.
Calculates the relative distance between the tip end position of the arm 1b and the interference avoidance area determined in step (1) to determine whether or not the work implement 1A has entered the interference avoidance area, and outputs a control signal to the comparison unit 7e. The area restriction control unit 7d operates the restriction area setting switch 14
The relative distance between the boundary 36 of the limit value set in the above and the tip position of the arm 1b calculated by the attitude calculation unit is calculated, and the control signal is compared with the comparison unit 7e based on the calculation result and the detection signal from each pressure sensor. Output to The comparison unit compares the magnitude of the control signal output from the interference prevention control unit with the magnitude of the control signal output from the area limit control unit, and outputs the control signal to the valve command calculation unit 7f. Proportional valve 11a,
Output values to 11b, 12a, 12b and 13 are calculated to control the opening / closing operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction having both an interference preventing function for preventing a working machine from interfering with a main body and an area limiting function for limiting an operating range of the working machine to an arbitrary limit value. The present invention relates to a work machine control device for a machine.

[0002]

2. Description of the Related Art Generally, a construction machine such as a hydraulic shovel has a working machine composed of a plurality of articulated movable members such as a boom, an arm, and a bucket, a plurality of hydraulic actuators for driving these movable members, and The working machine is provided with a plurality of operation levers for instructing the operation of each hydraulic actuator, and the working machine is rotatably connected to a main body having an operator cab.

[0003] In such a hydraulic excavator, as described in, for example, Japanese Utility Model Registration No. 2500452, when an operator operates each operating lever to bring the working machine close to the cab, the working machine is not operated. There is a possibility that the unit may interfere with the cab, and a unit provided with an interference prevention function for preventing interference between the working machine and the main body is employed. The interference prevention function sets an interference avoidance area around the driver's cab, and calculates position coordinates at a predetermined portion of the working machine based on output signals from a plurality of angle sensors.
A relative distance between a predetermined part of the work implement and the interference avoidance area is calculated, and when the predetermined part of the work implement enters the interference avoidance area, the operation of the work implement is automatically stopped in front of the cab. .

In such a hydraulic excavator,
For example, as described in Japanese Patent Application Laid-Open No. 9-53259, a limit value is set at an arbitrary position of a work machine, and the operating range of the work machine is set with respect to a boundary (horizontal plane) defined by the limit value. There is known an area restriction function that restricts the area. When the operator sets a limit value at an arbitrary position using an area limit setting switch or the like, the area limit function calculates position coordinates at a predetermined portion of the working machine based on output signals from a plurality of angle sensors, Calculate the relative distance between the predetermined part of the work machine and the boundary of the limit value,
The operating speed of the working machine is limited in accordance with the relative distance so that a part of the working machine does not exceed the boundary of the limit value. Therefore, for example, when the limit value is set at an arbitrary depth in the ground, it is possible to prevent piping installed at a position deeper than the limit value during excavation work from being damaged by the bucket tip, and When the limit value is set to an arbitrary height from the above, it is possible to prevent the electric wires and the like installed above the working machine from being damaged by the working machine.

[0005]

Since the control of the working machine by the above-described interference prevention function and the control of the working machine by the area limiting function are performed separately, the interference avoidance area set in advance around the operator cab is controlled. In the case where the boundary of the limit value is set at a position where the boundary does not overlap, the operating speed of the work implement can be controlled according to the distance to the interference avoidance area or the boundary of the limit value. However, if the boundary of the limit value is set at a position overlapping the interference avoidance area due to the topography of the work site, for example, the boundary of the height limit is set at a position overlapping the upper part of the interference avoidance area, or the boundary of the depth limit is set. Is set at a position that overlaps with the lower part of the interference avoidance area, there is a problem that it is not possible to appropriately control the work implement in a portion where the boundary of these limit values and the interference avoidance area overlap.

[0006]

According to the present invention, when a work machine approaches a portion where a boundary of a limit value and an interference avoidance area overlap, a control calculated by the interference prevention control means and the area limit control means respectively. It is assumed that, of the signals, a control signal that slows down the operating speed of the work implement is selected and controlled, or the operating speed of the work implement is controlled by giving priority to the interference prevention control over the area limit control. With this configuration, even when the working machine approaches the overlapping portion between the boundary of the limit value and the interference avoidance area, it is possible to appropriately control the operating speed of the working machine and reliably avoid interference with the cab. Therefore, the settable range of the boundary of the limit value and the interference avoidance area can be expanded.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a working machine control device for a construction machine according to the present invention, there is provided a working machine comprising a body having an operator's cab, a plurality of articulated movable members rotatably connected to the body, and A plurality of hydraulic actuators respectively driving the movable members, a plurality of operation means for instructing the operation of the plurality of movable members, and are driven in accordance with operation signals of the plurality of operation means, and supplied to the plurality of actuators. A plurality of hydraulic control valves for controlling the flow rate of pressure oil, a signal reduction unit for reducing an operation signal of the operation unit, an angle detector for detecting a relative angle between the plurality of movable members, and an output of the angle detector. Attitude calculation means for calculating a position of the work machine at an arbitrary part based on a signal, restriction area setting means capable of setting a boundary for limiting an operation range of the front device, And stores the interference avoidance area set around the controller, and when the work implement enters the interference avoidance area, outputs a first control signal to the signal reduction means to control the operation speed of the work implement. Controlling the operation speed of the work implement by outputting a second control signal to the signal deceleration means when the work implement approaches the boundary set by the area limit setting means. An area limiting control unit that performs a comparison between the first control signal and the second control signal when the work machine enters the interference avoidance area and approaches the boundary; And a signal comparing means for selecting a control signal having a lower operation speed and outputting the selected control signal to the signal decelerating means.

With this configuration, when the working machine approaches the overlapping portion between the limit value boundary and the interference avoidance area,
Of the first control signal calculated by the interference prevention control means and the second control signal calculated by the area restriction control means, the control signal that reduces the operating speed of the work implement is selected and used as the signal deceleration means. For output, it is possible to optimally control the operation speed of the work implement with respect to the boundary of the limit value and the interference avoidance area, and select the first control signal at a position where the work implement is closest to the cab. The work machine can be stopped.

According to another aspect of the present invention, there is provided a working machine control device for a construction machine, comprising: a main body having an operator's cab; and a working machine including a plurality of articulated movable members rotatably connected to the main body.
A plurality of hydraulic actuators respectively driving the plurality of movable members, a plurality of operation means for instructing the operation of the plurality of movable members, and driven in accordance with operation signals of the plurality of operation means; A plurality of hydraulic control valves for controlling the flow rate of the supplied pressure oil; a signal reduction unit for reducing an operation signal of the operation unit; an angle detector for detecting a relative angle between the plurality of movable members; and the angle detector Attitude calculation means for calculating the position of the work machine at an arbitrary part based on the output signal, restricted area setting means capable of setting a boundary for limiting the operation range of the front device, and setting around the main body. When the work implement enters the interference avoidance area, a first control signal is output to the signal deceleration means to reduce the operating speed of the work implement. An interference prevention control means for controlling, and when the work implement approaches the boundary set by the area restriction setting means, outputs a second control signal to the signal deceleration means to reduce the operating speed of the work implement. And an area limiting control means for controlling, when the work implement enters the interference avoidance area, invalidates the second control signal, and reduces the operation speed of the work implement only by the first control signal. It was configured to control.

With this configuration, when the working machine approaches the overlapping portion between the boundary of the limit value and the interference avoidance area,
The second control signal calculated by the area limit control means is invalidated, and the operating speed of the work machine is controlled using the first control signal calculated by the interference prevention control means. The operating speed of the working machine can be optimally controlled for each area, and it is possible to reliably prevent the working machine from interfering with the cab.

[0011]

Embodiments will be described with reference to the drawings.
FIG. 1 is a side view of a hydraulic excavator to which the present invention is applied, and FIG.
FIG. 3 is a plan view of the excavator, FIG. 3 is a circuit diagram of a hydraulic drive device provided in the excavator, FIG. 4 is a block diagram of a control device according to the first embodiment, and FIG. 5 is a boundary between an interference avoidance area and a limit value. FIG.

1 and 2, 1f denotes a traveling body driven by a left traveling motor 3f and a right traveling motor 3g.
1e has a driver's cab 3h, is arranged above the traveling body 1f,
The traveling body 1f and the revolving body 1e constitute a main body 1B of a hydraulic shovel. The revolving body is driven by a revolving motor 3e. 1a is a lower boom that is connected to a revolving superstructure 1e on the right side of the cab 3h and is rotatable vertically.
1d is an upper boom mounted on the distal end of the lower boom 1a and rotatable in the left-right direction, 1b is an arm mounted on the distal end of the upper boom 1d and rotatable in the vertical direction, 1c is an arm 1
b, which is mounted on the tip of the b and is rotatable in the vertical direction. The booms 1a and 1d, the arm 1b and the bucket 1
c is an articulated movable member, and the working machine 1A is constituted by the plurality of movable members. 3a is a boom cylinder for driving the lower boom 1a, 3b is an arm 1b
And 3c are offset cylinders for driving the upper boom 1d, and the arm 1b and the bucket 1c are connected to the lower boom 1 by the offset cylinder 3d.
translates laterally with respect to a. 6a is lower boom 1
This is a boom angle sensor provided at the fulcrum portion a, and detects a relative angle between the swing body 1e and the lower boom 1a. 6b
Is an arm angle sensor provided at a fulcrum of the arm 1b, and detects a relative angle between the upper boom 1d and the arm 1b. Reference numeral 6c denotes an offset angle sensor provided at a fulcrum of the upper boom 1d, and detects a relative angle between the lower boom 1a and the upper boom 1d.

In FIG. 3, 2 is a hydraulic pump, 8 is a pilot pump, 9a is an operating device for a boom, 9b is an operating device for an arm, 9c is an operating device for a bucket, and 9d is an operating device for an offset. The devices 9a to 9d are arranged in the operator's cab 3h, and command the operation of each of the cylinders 3a to 3d by the operation devices 9a to 9d. 10a is a boom flow control valve, 10b is an arm flow control valve, 10c is a bucket flow control valve, and 10d is an offset flow control valve. The boom operating device 9a and the hydraulic drive units 50a and 50b of the boom flow control valve 10a are connected by pilot pipes 40a and 40b, respectively, and when the operator operates the boom operating device 9a, the pilot piping 40a, The pilot oil is supplied to one of the hydraulic drive units 50a, 50b of the boom flow control valve 10a via one of the boom cylinders 40b.
a is controlled. Similarly, the operating device 9b for the arm and the hydraulic drive units 51a, 51b of the flow control valve 10b for the arm are connected by pilot pipes 41a, 41b, respectively. 52a, 52b are connected by pilot pipes 42a, 42b, respectively, and the offset operating device 9d
And the hydraulic drive unit 53a of the offset flow control valve 10d,
53b are connected by pilot pipes 43a and 43b, respectively, and the operator operates the arm operating device 9b, the bucket operating device 9c, and the offset operating device 9d.
Are operated to respectively control the flow control valves 10b, 1
Pilot oil is supplied to 0c and 10d, and as a result, each of the cylinders 3b, 3c and 3d is controlled.

Further, the aforementioned boom pilot pipe 4
0a and 40b are provided with electromagnetic proportional valves 11a and 11b, respectively.
Electromagnetic proportional valves 12a and 12b are provided in 1b, respectively, and an electromagnetic proportional valve 13 is provided in the offset pilot pipe 43b. Further, boom pilot pipes 40a and 40b are provided with pressure sensors 60a and 60b for detecting respective pressures, and arm pilot pipes 41a and 41b are provided with pressure sensors 61a and 61b for detecting the pressure of each pilot oil. Have been. Reference numeral 7 denotes a control device, and the control device 7 includes the angle sensors 6a, 6
b, 6c and each pressure sensor 60a, 60b, 61a, 61
b and a signal from the restriction area setting switch 14 are input to each of the electromagnetic proportional valves 11a, 11b, 12a, 12b, 1
3 to output a predetermined control signal. In the first embodiment,
Each of the electromagnetic proportional valves 11a, 11b, 12a, 12b, and 13 is normally fully opened, and the throttle amount increases as the current signal output from the control device 7 increases.

As shown in FIG. 4, the control device 7 includes various dimension storage units 7a, posture calculation units 7b, interference prevention control units 7
c, an area limit control section 7d, a comparison section 7e, and a valve command calculation section 7f. The various dimension storage unit 7a stores various dimensions required to calculate a predetermined portion of the work machine 1A, and the posture calculation unit 7b stores the dimensions stored in the various dimension storage unit 7a and the angle sensors 6a, 6b, 6c
Calculates the position coordinates of the work implement 1A at a predetermined part based on the detection signal. In the case of the present embodiment, the arm 1b
Although the coordinates of the tip position are calculated, the coordinates of the tip position of the bucket 1c, for example, may be calculated.

The interference prevention control section 7c stores an interference avoidance area 35 set in advance around the revolving unit 1e including the cab 3h. The interference prevention control section 7c calculates the interference avoidance area 35 by the attitude calculation section 7b. By calculating the relative distance between the position of the tip of the arm 1b and the interference avoidance area 35, it is determined whether or not a part of the work machine 1A has entered the interference avoidance area 35. When it is determined that a part of the work implement 1A has entered the interference avoidance area 35, the operation speed of the work implement 1A is reduced according to the relative distance between the work implement 1A and the interference avoidance area 35. The control signal is output to the comparison unit 7e. In this case, the control speed is reduced as the vehicle is closer to the driver's cab 3h, and a control signal for stopping the vehicle when the vehicle travels within a certain predetermined distance is output.

The area limit control unit 7d sets a limit value boundary 36 (see a broken line in FIG. 5) at an arbitrary position in the vertical direction of the work machine 1A based on the instruction signal from the limit area setting switch 14. Is stored in the internal RAM.
In the case of this embodiment, when the operator operates the restricted area setting switch 14 with the work implement 1A in a predetermined posture,
Although the present arbitrary position of the work machine 1A is stored as the limit value boundary 36, the limit value is determined from the absolute position of the work machine 1A by using an input device such as a ten key instead of the restricted area setting switch 14. May be set. The area limit control unit 7d calculates the relative distance between the boundary 36 of the limit value set by the limit area setting switch 14 and the tip end position of the arm 1b calculated by the attitude calculation unit 7b. Sensor 60a, 6
Based on the detection signals from 0b, 61a, 61b, a control signal corresponding to the relative distance between work implement 1A and boundary 36 is output to comparison section 7e. In this case as well, a control signal is output to decrease the operation speed in the direction approaching the boundary 36 between the arm 1b and the lower boom 1a as the relative distance becomes shorter.

The comparator 7e compares the magnitudes of the respective control signals output from the interference prevention controller 7c and the area limit controller 7d, selects the control signal having the larger value, and calculates this by the valve command calculation. Output to the unit 7f. The valve command calculation unit 7f determines each electromagnetic proportional valve 11 based on the control signal.
a, 11b, 12a, 12b, and 13 to calculate output values to each of the electromagnetic proportional valves 11a, 11b, 12a, 12b, 1
3 is controlled.

For example, the work implement 1A is controlled by the interference prevention controller 7c.
Is determined not to have entered the interference avoidance area 35, that is, when the work implement 1A does not interfere with the revolving unit 1e, the interference prevention control unit 7c sends the minimum level 0 control signal to the comparison unit 7e. The comparator 7e selects the control signal output from the area restriction controller 7d to control the opening / closing operation of each of the electromagnetic proportional valves 11a, 11b, 12a, 12b, and 13. In this case, the area restriction control unit 7d operates the work implement 1 based on an operation signal from each of the operation devices 9a, 9b, 9d according to the relative distance between the work implement 1A and the boundary 36 of the limit value.
A control signal for reducing the operating speed of A
A is controlled not to operate beyond the boundary 36.

On the other hand, when the interference prevention control unit 7c determines that the work machine 1A has entered the interference avoidance area 35, the interference prevention control unit 7c compares the control signal whose level increases in accordance with the degree of the intrusion with the comparison unit. 7e. Here, when the work implement 1A is separated from the boundary 36 of the limit value, that is, when the operation of the work implement 1A is not restricted with respect to the boundary 36, the area restriction control unit 7d sends the minimum level 0 to the comparison unit 7e.
The comparison unit 7e selects the control signal output from the interference prevention control unit 7c to control the opening / closing operation of each of the electromagnetic proportional valves 11a, 11b, 12a, 12b, and 13. At this time, when the work implement 1A enters the interference avoidance area 35, the interference prevention control unit 7c first outputs a control signal slightly larger than the minimum level to the comparison unit 7e, and the work implement 1A
Is controlled so as to reduce the operation speed in the direction approaching the revolving unit 1e. Then, the work implement 1A further moves
e, and when approaching more than a predetermined distance, the interference prevention control unit 7c outputs a maximum control signal to the comparison unit 7e, and the electromagnetic proportional valves 11a, 11b, 12a, 12b, 1
3 is in the fully closed state, so that each of the operating devices 9a, 9b, 9d
The pilot pressure is not supplied to the flow control valves 10a, 10b, and 10d irrespective of the operation described above, and the work machine 1A is controlled to stop automatically before the revolving unit 1e.

As shown in FIG. 5, the boundary 36 of the limit value is set at a position overlapping with the interference avoiding area 35 due to the topography of the work site and the like, and the work machine 1A is in contact with the boundary 36 and the interference avoiding area 35. , The comparison unit 7e selects the larger one of the control signals output from the interference prevention control unit 7c and the area restriction control unit 7d, and outputs this control signal to the valve command calculation unit 7f. Therefore, the working machine 1
When A enters the interference avoidance area 35, the working machine is operated based on the control signal of the lower one of the operation speed calculated by the interference prevention control unit 7c and the operation speed calculated by the area restriction control unit 7d. The operating speed of 1A is reduced. However,
When the work implement 1A approaches the revolving unit 1e to a very short distance, the interference prevention control unit 7c outputs the maximum control signal to the comparison unit 7e as described above. Therefore, the comparison unit 7e outputs this control signal to the valve command calculation unit 7f. And the working machine 1A
Automatically stops before.

As described above, according to the first embodiment, when the work implement 1A approaches the overlapping portion between the limit value boundary 36 and the interference avoidance area 35, the control calculated by the interference prevention control section 7c. Of the signals and the control signals calculated by the area restriction control unit 7d, the control signal that causes the operating speed of the work implement 1A to be slower is selected and output to the valve command calculation unit 7f.
The operating speed of the work implement 1A can be optimally controlled with respect to the boundary 36 of the limit value and the interference avoidance area 35, and the work implement 1A can be reliably stopped just before the revolving unit 1e. Therefore, it is possible to set the boundary 36 of the excavation restriction at a position overlapping the lower part of the interference avoidance area 35 and set the boundary of the height restriction at a position overlapping the upper part of the interference avoidance area 35 as shown in FIG. Also, the settable range of the interference avoidance area 35 can be expanded.

In the first embodiment, the operating devices 9a to 9d are operating means, the valve command calculating section 7f is signal reducing means, the angle sensors 6a, 6b, 6c are angle detectors, and the attitude calculating section 7b Is the attitude calculation means, the restricted area setting switch 14 is the restricted area setting means, and the interference prevention controller 7c
Represents the interference prevention control means, the area restriction control section 7d constitutes the area restriction control means, and the comparison section 7e constitutes the signal comparison means.

FIG. 6 is a block diagram of a control device according to the second embodiment, and portions corresponding to FIG. 4 are denoted by the same reference numerals.

The present embodiment is different from the above-described first embodiment in that the control device 7 has a judging unit 7g instead of the comparing unit 7e. When it is determined that 1A has entered the interference avoidance area 35, the control signal output from the area restriction control unit 7d is invalidated, and the control signal output from the interference prevention control unit 7c is sent to the valve command calculation unit 7f. That is to output.

In the second embodiment configured as described above, when the work implement 1A approaches the overlapping portion between the limit value boundary 36 and the interference avoidance area 35, the control signal calculated by the interference prevention control section 7c. Of the control signals calculated by the area restriction control unit 7d, the control signal calculated by the area restriction control unit 7d is invalidated, and the control signal calculated by the interference prevention control unit 7c is given priority over the valve command calculation unit. 7f. Therefore, similarly to the above-described first embodiment, the limit value boundary 3
6 and the interference avoidance area 35, the operating speed of the work implement 1A is optimally controlled, and the work implement 1A can be reliably stopped in front of the revolving unit 1e. The settable range of 35 can be expanded.

[0027]

The present invention is embodied in the form described above and has the following effects.

When the work machine approaches a portion where the boundary of the limit value and the interference avoidance area overlap, the control signals calculated by the interference prevention control means and the area limit control means respectively include:
To control the operation speed of the work equipment by selecting the control signal that slows down the operation speed of the work equipment, or to control the operation speed of the work equipment by giving priority to the interference prevention control over the area limit control,
Even when the work equipment approaches the overlapping part of the boundary of the limit value and the interference avoidance area, the operating speed of the work equipment can be appropriately controlled to reliably avoid interference with the cab, and the boundary of the limit value can be avoided. And the settable range of the interference avoidance area can be expanded.

[Brief description of the drawings]

FIG. 1 is a side view of a hydraulic shovel to which the present invention is applied.

FIG. 2 is a plan view of the excavator.

FIG. 3 is a circuit diagram of a hydraulic drive device provided in the excavator.

FIG. 4 is a block diagram of a control device according to the first embodiment of the present invention.

FIG. 5 is an explanatory diagram showing a boundary between an interference avoidance area and a limit value.

FIG. 6 is a block diagram of a control device according to a second embodiment of the present invention.

[Explanation of symbols]

 1a Lower boom 1b Arm 1c Bucket 1e Revolving body 1f Traveling body 1A Work machine 1B Main body 2 Hydraulic pump 3h Operating room 3a, 3b, 3c, 3d Cylinder 6a, 6b, 6c Angle sensor 7 Control device 7a Various dimension storage unit 7b Attitude calculation unit 7c Interference prevention control unit 7d Area restriction control unit 7e Comparison unit 7f Valve command calculation unit 7g Judgment unit 8 Pilot pump 9a, 9b, 9c, 9d Operating device 10a, 10b, 10c, 10d Flow control valves 11a, 11b, 12a, 12b , 13 Electromagnetic proportional valve 14 Restricted area setting switch 60a, 60b, 61a, 61b Pressure sensor

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Yusuke Kajita 650, Kandamachi, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. (72) Inventor Toshiaki Nishida 650, Kandamachi, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery F term in Tsuchiura Plant (reference) 2D003 AA01 AB03 BA07 BB11 DA03 DA04 DB02 DB04 2D015 GA02 GA03 GB04

Claims (2)

[Claims] A main body having an operator's cab, a working machine including a plurality of articulated movable members rotatably connected to the main body, a plurality of hydraulic actuators respectively driving the plurality of movable members, A plurality of operation means for instructing the operation of the plurality of movable members; and a plurality of hydraulic control valves that are driven according to operation signals of the plurality of operation means and control a flow rate of pressure oil supplied to the plurality of actuators, A signal deceleration unit that reduces an operation signal of the operation unit; an angle detector that detects a relative angle between the plurality of movable members; and a position of the work machine at an arbitrary position based on an output signal of the angle detector. Attitude calculation means to perform; a limit area setting means capable of setting a boundary for limiting the operation range of the front device; and an interference avoidance area set around the main body. When the work machine enters the interference avoidance area, outputs a first control signal to the signal deceleration means to control the operation speed of the work machine; and When the vehicle approaches the boundary set by the restriction setting unit, a second control signal is output to the signal deceleration unit to control the operating speed of the work machine; When invading the avoidance area and approaching the boundary, the first control signal and the second control signal are compared, and a control signal with which the operation speed of the working machine is reduced is selected. A work machine control device for a construction machine, comprising: a signal comparison unit that outputs the signal to the signal deceleration unit. 2. A main body having a driver's cab, a working machine including a plurality of articulated movable members rotatably connected to the main body, a plurality of hydraulic actuators respectively driving the plurality of movable members, A plurality of operation means for instructing the operation of the plurality of movable members; and a plurality of hydraulic control valves that are driven according to operation signals of the plurality of operation means and control a flow rate of pressure oil supplied to the plurality of actuators, A signal deceleration unit that reduces an operation signal of the operation unit; an angle detector that detects a relative angle between the plurality of movable members; and a position of the work machine at an arbitrary position based on an output signal of the angle detector. Attitude calculation means to perform; a limit area setting means capable of setting a boundary for limiting the operation range of the front device; and an interference avoidance area set around the main body. When the work machine enters the interference avoidance area, outputs a first control signal to the signal deceleration means to control the operation speed of the work machine; and When the vehicle approaches the boundary set by the limit setting unit, the second unit outputs a second control signal to the signal deceleration unit to control the operating speed of the work machine. When the vehicle enters the interference avoidance area, the second control signal is invalidated, and the operating speed of the work machine is controlled only by the first control signal. Machine control device.