JP2022126348A - Work machine - Google Patents

Abstract

To provide a work machine capable of improving both safety and work efficiency by reducing possibility of contact with a person existing in a periphery.SOLUTION: A work machine calculates a distance between a work device and a person based on a posture of the work device, and reduces its operation speed when the distance is equal to or less than a threshold value.SELECTED DRAWING: Figure 10

Description

The present invention relates to work machines that perform work operations.

A work machine is a machine that carries out various works on behalf of a person, for example, a hydraulic excavator driven by hydraulic pressure is one example. When a hydraulic excavator is used to bury a clay pipe or the like, the hydraulic excavator and an auxiliary worker may work together. If the auxiliary operator is in the blind spot of the work equipment or at the bottom of a ditch where the operator cannot directly see the auxiliary operator, the operator may operate the work equipment without noticing the presence of the auxiliary operator, causing the work equipment to stop working. Risk of contact with auxiliary workers.

Patent Document 1 below describes a hydraulic excavator that divides the circumference of a hydraulic excavator into a plurality of detection spaces, and allows the movement of the vehicle body in a direction other than the direction toward the object when an object (including a person) is detected in one of them. described.

WO2019/168122

In Patent Document 1, it is prohibited to operate the working machine in the direction in which the object is detected. This may reduce work efficiency. Furthermore, even if an object that does not interfere with the work is detected, the work may be hindered because movement toward the object is prohibited.

The present invention has been made in view of the above problems, and by reducing the possibility of contact with people in the surroundings, it is possible to achieve both safety and work efficiency. The purpose is to provide a machine.

The working machine according to the present invention calculates the distance between the working device and the person based on the posture of the working device, and reduces the operating speed of the working device if the distance is equal to or less than a threshold.

According to the working machine of the present invention, even when a person is detected, the operation of the working machine is not immediately stopped, and the operating speed is gradually reduced. As a result, it is possible to ensure the safety of people and avoid an excessive decrease in work efficiency.

It is a side view which shows the hydraulic excavator 301 which concerns on embodiment. 3 is a side view of the hydraulic excavator 301. FIG. 3 is a top view of the hydraulic excavator 301. FIG. 3 is a configuration diagram of a control device that controls the hydraulic excavator 301. FIG. 3 is a configuration diagram of a control device that controls the hydraulic excavator 301. FIG. 3 is a functional configuration diagram of the controller 100; FIG. 4 shows a configuration example of a data table describing the relationship between the pilot pressure and the hydraulic actuator target operating speed; 4 shows an example configuration of a data table describing the relationship between the maximum operating pilot pressure and the hydraulic pump target discharge flow rate. FIG. 10 shows a configuration example of a data table that describes the relationship between the amount of displacement of the spool of the flow control valve and the opening area of the flow control valve; FIG. FIG. 4 shows an example of a data table describing the relationship between operating pilot pressure and oil flow; FIG. It is an example of the peripheral area of the work machine 300 . FIG. 10 is a diagram illustrating a method for human detection unit 100C to calculate the distance between work implement 300 and a person. FIG. 10 is a diagram illustrating a method for human detection unit 100C to calculate the distance between work implement 300 and a person. 4 is a flowchart for explaining processing performed by a control calculation unit 100E; It is an example of a data table used by the control calculation unit 100E in S1003. It is an example of a data table used for converting a target operating speed and a target discharge flow rate into target pressures. FIG. 10 is a diagram showing how a collision with a person is avoided by reducing the operating speed of the working device;

FIG. 1 is a side view showing a hydraulic excavator 301 according to an embodiment of the invention. A hydraulic excavator 301 includes a lower traveling body 303 having a pair of left and right belts 302a and 302b, an upper revolving body 304 rotatably provided above the lower traveling body 303, and a multi-joint structure having one end connected to the upper revolving body 304. type working machine 300 .

Travel motors 318a and 318b are mounted on the lower travel body 303 to drive the belts 302a and 302b, respectively. A driver's cab 305 is installed on the front left side of the upper revolving body 304 . A working machine 300 is attached to the front central portion of the upper revolving body 304 .

A work machine 300 is attached to a boom foot (not shown) provided at the front central portion of an upper revolving body 304 so as to be able to swing vertically, and to the tip of the boom 310 so as to be able to swing forward and backward. An arm 312 and a bucket 314 that is a working tool (attachment) attached to the tip of the arm 312 so as to be vertically rotatable are provided. Boom 310 , arm 312 , and bucket 314 function as a work device used by work machine 300 to perform work operations.

The work machine 300 includes a boom cylinder 311, which is a hydraulic actuator connected to a boom foot and a boom 310 to vertically swing the boom 310, and a hydraulic actuator connected to the boom 310 and an arm 312 to vertically swing the arm 312. and a bucket cylinder 315 of a hydraulic actuator connected to the arm 312 and the bucket 314 to rotate the bucket 314 in the vertical direction.

Link 320 connects bucket 314 and bucket cylinder 315 , and link 321 connects arm 312 , bucket cylinder 315 and link 320 .

FIG. 2 is a side view of the excavator 301. FIG. Camera 104L on the upper surface of cab 305, camera 104R on the upper surface of upper rotating body 304, cameras 105L and 105R on both sides of boom 310, cameras 106L and 106R on both sides of arm 312, and camera 107 on the upper surface of arm 312. are installed respectively. Each camera operates as a human detector that detects people around work machine 300 .

Each camera captures the area enclosed by the dashed line extending from the center of the lens. By arranging the cameras so that their photographing areas overlap, it is possible to reliably detect a person present around work machine 300 . Although the cameras are attached to both sides of the boom 310 and the arm 312 in this embodiment, cameras may be attached to the lower surfaces of each instead.

An image captured by each camera is subjected to image processing by a controller 100 (described later) installed in the driver's cab 305 and used to detect people present in the vicinity. An ultrasonic sensor, a LiDAR (distance measuring sensor), or the like may be used instead of a camera as a means for detecting people, or a plurality of these may be used in combination.

Inertial measurement devices 101, 102, and 103 (attitude detectors) are attached to the boom 310, arm 312, and link 321, respectively. Inertial measurement units 101-103 measure angles with respect to a reference (eg, horizontal ground). Controller 100 calculates the attitude of work implement 300 using the angle measured by each inertial measurement device. A potentiometer attached to each joint or a displacement sensor attached to each cylinder may be used as the attitude detector of work machine 300 instead of the inertial measurement device.

FIG. 3 is a top view of the excavator 301. FIG. The detectable range of each camera overlaps the detectable range of at least one of the other cameras.

4A and 4B are configuration diagrams of a control device that controls the excavator 301. FIG. For convenience of description, the block diagram of the control device is divided into two drawings. The locations marked "A" in the figures are connected to each other between FIGS. 4A and 4B.

1 and 2 are variable displacement hydraulic pumps (hereinafter referred to as hydraulic pumps) driven by the prime mover, 1A and 2A are displacement variable members (hereinafter represented by swash plates) that change the displacement of the hydraulic pumps, 1B and 2B. is a regulator for controlling tilting of the swash plates 1A and 2A.

311 is a boom cylinder; 313 is an arm cylinder; 315 is a bucket cylinder; 319 is a swing motor; Reference numerals 5 and 6 denote arm flow control valves for controlling supply and discharge of pressure oil to the arm cylinder 313, and 7 is a bucket flow control valve for controlling supply and discharge of pressure oil to the bucket cylinder 315. FIG. In addition to these, the swing motor 319, the left and right travel motors 318a and 318b, and the hydraulic actuators of the attachment (not shown) are also provided with flow control valves for controlling the supply and discharge of these pressurized oil. The boom flow control valves 3 and 4, the arm flow control valves 5 and 6, and the bucket flow control valve 7 are operated by pilot pressure generated in proportion to the operation amount by the corresponding operating lever devices 8, 9, and 10, respectively. be.

11A is a pressure sensor that detects the pilot pressure on the boom raising side, 11B is a pressure sensor that detects the pilot pressure on the boom lowering side, 12A is a pressure sensor that detects the pilot pressure on the arm pulling side, and 12B is the pilot pressure on the arm pushing side. 13A is a pressure sensor that detects the pilot pressure on the bucket entrainment side, and 13B is a pressure sensor that detects the pilot pressure on the bucket discharge side.

Controller 100 controls pressure values output by pressure sensors 11A, 11B, 12A, 12B, 13A, and 13B, angles output by inertial measurement devices 101, 102, and 103, cameras 104L, 104R, 105L, 105R, 106L, and 106R, By receiving the video signal of 107 and performing predetermined arithmetic processing (details of which will be described later), a Calculate the current value to be output to the solenoid valves 1C and 2C. The controller 100 outputs a current for driving each solenoid valve according to the calculated current value.

FIG. 5 is a functional configuration diagram of the controller 100. As shown in FIG. The functions of the controller 100 are configured by a target operating speed calculation section 100A, an attitude calculation section 100B, a human detection section 100C, a hydraulic pump volume calculation section 100D, a control calculation section 100E, and an output processing section 100F.

The target operating speed calculator 100A calculates the relationship between the pilot pressure and the hydraulic actuator target operating speed as shown in FIG. The target operating speed of each actuator is calculated using the stored table.

Attitude calculation unit 100B calculates the attitude of work implement 300 using the angles of boom 310, arm 312, and link 321 with respect to the horizontal plane detected by inertial measurement devices 101, 102, and 103, the dimensions between the joints, and the like.

Human detection unit 100C detects the presence of a person around work machine 300 by pattern recognition or the like from images captured by cameras 104L, 104R, 105L, 105R, 106L, 106R, and 107. FIG. When a person is detected, person detection unit 100C calculates the distance between work implement 300 and the person based on the detected distance and direction. A calculation method will be described later.

Based on each pilot pressure, the hydraulic pump capacity calculation unit 100D uses a table that stores the relationship between the maximum value of each pilot pressure and the hydraulic pump target discharge flow rate as shown in FIG. 6B to be described later. , respectively, are calculated.

The control calculation unit 100E calculates the target motion speed of each actuator calculated by the target motion speed calculation unit 100A, the posture of the working machine 300 calculated by the posture calculation unit 100B, and the detection information of the person 200 in the restricted area calculated by the person detection unit 100C. , the distance between the work machine 300 and the person 200 calculated by the human detection unit 100C, and the target discharge flow rate of the hydraulic pumps 1 and 2 calculated by the hydraulic pump volume calculation unit 100D. A current value for driving is calculated, and the calculation result is output to the output processing unit 100F.

The output processing unit 100F outputs the drive current having the current value calculated by the control calculation unit 100E to each electromagnetic valve.

FIG. 6A shows a configuration example of a data table describing the relationship between pilot pressure and hydraulic actuator target operating speed. This data table can be stored in a storage device or the like within the controller 100 . The same applies to a data table to be described later. The target operating speed calculator 100A acquires the target operating speed Vtgt of the hydraulic actuator corresponding to the operation pilot pressure Pi by referring to the data table of FIG. 6A.

FIG. 6B is a configuration example of a data table describing the relationship between the maximum operating pilot pressure among the pilot pressures detected by the pilot pressure sensors 11A, 11B, 12A, 12B, 13A, and 13B and the hydraulic pump target discharge flow rate. indicates The hydraulic pump volume calculation unit 100D acquires the hydraulic pump target discharge flow rate Qtgt corresponding to the maximum operation pilot pressure Pimax by referring to the data table of FIG. 6B.

FIG. 6C shows a configuration example of a data table describing the relationship between the amount of displacement of the spool of the flow control valve and the opening area of the flow control valve. The hydraulic circuit used by the hydraulic excavator 301 in this embodiment to drive each part includes a meter-in circuit (a circuit for controlling pressure oil supplied to the hydraulic actuator by a flow control valve) and a meter-out circuit (a circuit discharged from the hydraulic actuator). A circuit for controlling pressure oil by a flow control valve) and a bleed-off circuit (a circuit for controlling pressure oil returning to the hydraulic tank by a flow control valve). By referring to the data table in FIG. 6C, the hydraulic pump volume calculation unit 100D calculates the flow rate (meter-in flow rate) of pressure oil supplied from the hydraulic pump to the hydraulic actuator and the flow rate from the hydraulic pump to the tank via the center bypass flow path. The flow rate of recirculated pressure oil (bleed-off flow rate) is controlled according to the spool displacement amount (that is, according to the pilot pressure).

That is, for example, an open center type hydraulic circuit can be used as the hydraulic circuit in this embodiment. In the open center hydraulic circuit, when the spool of the flow control valve is in the neutral position, the pump and the tank are connected by the center bypass oil passage of the flow control valve. Since only the center bypass oil passage is open when the pilot pressure is zero, all the pressure oil is returned to the tank as the bleed-off flow rate. On the other hand, as the operation pilot pressure increases, the center bypass oil passage is throttled by the center bypass throttle of the flow control valve (opening area decreases), and the meter-in throttle and meter-out throttle of the flow control valve begin to open (opening area increases). ) Part of the pressure oil is returned to the tank, while the rest of the pressure oil is supplied to the hydraulic actuator. When the operating pilot pressure is maximum, the center bypass oil passage is closed by the center bypass throttle, and only the meter-in throttle and meter-out throttle are open, so all the pressure oil is supplied to the hydraulic actuators.

FIG. 6D shows an example data table describing the relationship between operating pilot pressure and oil flow. From the relationship between the pilot pressure and the hydraulic actuator target operating speed shown in FIG. 6A, the relationship between the pilot pressure and the meter-in flow rate indicated by the solid line in FIG. , the relationship between the pilot pressure and the hydraulic pump target discharge flow rate shown in the table of FIG. 6B can be obtained. The hydraulic pump volume calculation unit 100D may dynamically calculate the data table of FIG. 6B using the data tables of FIGS. 6A, 6C, and 6D, or may calculate the data table of FIG. The results may be held and used to perform control calculations.

FIG. 7 is an example of a peripheral area of work implement 300 . The controller 100 divides and sets the surrounding area of the work machine 300 into the following two areas: (a) a detection area that only detects the presence of a person; A restricted area in which the operating speed of the work implement 300 is reduced by arithmetic processing described later. The restricted area coincides with the movable area of work implement 300 in the largest state. The size of the restricted area is variable in the longitudinal direction and the vertical direction with respect to the vehicle body of the hydraulic excavator 301 according to the attitude of the working machine 300 . The larger the work machine 300 moves (that is, the smaller the distance D between the work machine 300 and the person 200), the larger the controller 100 sets the size of the restricted area. By configuring the restricted area in this way, even though work is being performed with work machine 300 involved, the operating speed of work machine 300 can be reduced by detecting a person other than the assistant worker at the end of the movable area. can be prevented from being reduced and work efficiency being lowered. In other words, it is possible to achieve both safety and work efficiency by distinguishing between the area where the operation speed is restricted and the area where no restriction is set.

FIG. 8 is a diagram illustrating a method for human detection unit 100C to calculate the distance between work machine 300 and a person. Assume that a person 200 exists in front of bucket 314 and is detected by the image of camera 107 attached to the upper surface of arm 312 .

When a coordinate system is taken with the center of rotation of the upper rotating body 304 as the origin as shown in FIG. are projected onto the XY plane and the XZ plane, they are represented by (a) Lxy, Lxz and (b) θxy, θxz, respectively.

The coordinates (Xc, Yc, Zc) of the lens center of the camera 107 with respect to the origin are expressed as follows. Lsx and Lsz are calculated as follows using the previously stored dimensions of boom 310, the mounting position of camera 107 with respect to arm 312, and the angles of boom 310 and arm 312 detected by inertial measurement devices 101 and 102, respectively. be able to.

(Xc, Yc, Zc) = (Lsx, 0, Lsz)

Using the coordinates (Xc, Yc, Zc) of the camera 107 and the angles θs, Lxy, Lxz, θxy, and θxz formed by the center line of the camera 107 with the vertical, the coordinates (Xh, Yh, Zh) of the person 200 with respect to the origin are as follows. is represented as The angle θs formed between the center line of the camera 107 and the vertical can be calculated using the mounting angle of the camera 107 with respect to the arm 312 and the angle of the arm 312 detected by the inertial measurement device 102 .

(Xh, Yh, Zh) =
(
Lsx+Lxz·sin(θxz+θs),
Lxv·sin θxy,
Lsz−Lxz・cos(θxz+θs)
)

FIG. 9 is a diagram illustrating a method for human detection unit 100C to calculate the distance between work machine 300 and a person. Human detection unit 100C calculates the distance between work machine 300 and person 200 using the posture of work machine 300 calculated by posture calculation unit 100B and the outer shape information of boom 310, arm 312, and bucket 314. As shown in FIG. 9 , a plurality of points are arranged on the outer shape as the outer shape information of bucket 314 , and the coordinates of each point are calculated according to the attitude of work implement 300 . This calculation is also performed for boom 310 and arm 312 . Human detection unit 100</b>C calculates the distance between the coordinates of these points and the coordinates (Xh, Yh, Zh) of person 200 and adopts the shortest distance as the distance between work machine 300 and person 200 .

FIG. 10 is a flowchart for explaining the processing performed by the control calculation unit 100E. Each step in FIG. 10 will be described below.

(Fig. 10: Step S1001)
When the human 200 is detected in the restricted area while the driver is operating the work machine 300, the control calculation unit 100E continues to operate each actuator at the current target operating speed based on the current attitude of the work machine 300. The attitude of work implement 300 after a predetermined time period is calculated. Control calculation unit 100E estimates distance D between work implement 300 and person 200 based on the calculated posture. The calculation procedure has been described with reference to FIGS. 8 and 9. FIG.

(Fig. 10: Step S1002)
If the distance D estimated in S1001 is equal to or less than the threshold value Dth, the process proceeds to S1003; otherwise, the process returns to S1001.

(Fig. 10: Step S1003)
Control calculation unit 100E reduces the target operating speed of work implement 300 according to distance D. FIG. A specific example of the processing in this step will be described with reference to FIG. 11 described later.

(Fig. 10: Step S1004)
Control calculation unit 100E recalculates the attitude of work implement 300 and distance D in the same manner as in S1001. If the distance D is greater than the previous calculation, the process proceeds to S1006; otherwise, the process proceeds to S1005. That is, if the work machine 300 and the worker 200 move away from each other every time the distance D is calculated, the process proceeds to S1006, and they approach each other (for example, the worker 200 does not move from the spot or approaches the work machine 300). come), the process advances to S1005.

(Fig. 10: Step S1004: Supplement)
The previous calculated value of the distance D is the value calculated in S1001 when S1004 is performed for the first time, and the calculated value when S1004 was performed last time when S1004 is performed for the second time or later.

(Fig. 10: Step S1005)
The control calculation unit 100E returns to S1003 if the driver has operated the operation lever devices 8, 9, and 10, and terminates this flowchart if the driver has not operated them. That is, this flow chart continues until the driver finishes the operation.

(Fig. 10: Step S1005: Supplement)
When the driver inputs an operation input different from the current work operation to the operation lever devices 8, 9, 10, the distance D does not always become smaller. Therefore, if it is estimated that the distance D will increase based on the details of the operation, it may not be necessary to further reduce the target motion speed when returning to S1003. On the other hand, if it is desired to further improve safety, it may be assumed that the possibility of contact increases as long as the operation input is performed, and the target motion speed may be further reduced regardless of the operation content. The same applies to S1006 and S1007, which will be described later.

(Fig. 10: Steps S1006-S1007)
The control calculation unit 100E maintains the reduced target operating speed until the driver finishes operating the operation lever devices 8, 9, and 10 (S1007: Yes). When the distance D gradually increases, the distance between the person 200 and the work implement 300 gradually increases, so originally, it is not necessary to maintain the state where the target operation speed is reduced. However, in order to prompt the driver to stop the hydraulic excavator 301 and check the surroundings, this step maintains the state where the target operation speed is reduced.

FIG. 11 is an example of a data table used by the control calculation unit 100E in S1003. A reduction rate α of the target operating speed Vtgt with respect to the distance D is defined in advance in a data table as shown in FIG. The data table may be stored in the controller 100. FIG. The control calculation unit 100E reduces the target operating speed by multiplying the target operating speed of each actuator and the target discharge flow rate of the hydraulic pumps 1 and 2 by the reduction rate α. When the distance D 1 reaches Dmin, the target operating speed is reduced to 0 (that is, the working device is stopped).

FIG. 12 is an example of a data table used to convert the target operating speed and target discharge flow rate into target pressures. The control calculation unit 100E calculates the target operating speed of each actuator and the target discharge flow rate of the hydraulic pumps 1 and 2 using a data table as shown in FIG. Each is converted to the target pressure of the electromagnetic valve provided in the regulator of the pump. By reducing the target operating speed of each actuator from Vtgt before reduction to Vtgt', the target pressure of the solenoid valve provided in the pilot circuit is reduced from Pitgt to Pitgt'. As a result, the amount of displacement of the spool of the flow control valve returns to the neutral position, the meter-in throttle and the meter-out throttle are both throttled, and the center bypass throttle is opened. By reducing the target discharge flow rate of the hydraulic pumps 1 and 2 from Qtgt before reduction to Qtgt', the target pressure of the solenoid valve provided in the regulator is reduced from Pptgt to Pptgt'.

FIG. 13 is a diagram showing how a collision with a person is avoided by reducing the operating speed of the working device. When man 200 is detected in front of work machine 300, controller 100 determines the attitude of work machine 300 after a predetermined time (after t seconds in FIG. 13) and the distance D between man 200 and work machine 300 at that time. ' is estimated. When the distance D' is equal to or less than the threshold value Dth, the operation speed is reduced by multiplying the target operation speed by the reduction rate α according to the flowchart of FIG. As a result, the actual distance D'' between the person 200 and the work implement 300 after t seconds becomes larger than the estimated distance D'. Therefore, the possibility of colliding with a person can be reduced as compared with the case where the motion is continued without reducing the motion speed. Furthermore, instead of immediately stopping the operation of the work machine 300 (or prohibiting the movement toward the person 200), the operation speed is gradually reduced according to the distance D, so that the person 200 can move while continuing the work. can lower the possibility of contact with That is, it is possible to achieve both work efficiency and safety.

<Regarding Modifications of the Present Invention>
In the above embodiment, each functional unit included in the controller 100 can be configured by hardware such as a circuit device implementing the function, or configured by an arithmetic unit executing software implementing the function. can also

In the above embodiment, an example in which the cameras are arranged around the working device (boom 310/arm 312/bucket 314) has been described, but cameras and other human detectors can also be arranged in other parts. For example, human detectors may be arranged on the upper and lower surfaces of the boom 310, the lower surface of the arm 312, and the like. It is desirable to arrange at least two human detectors so that at least a part of their detection ranges overlap each other. Alternatively, in a working machine such as a hydraulic excavator in which the working arm is extended in front of the working machine 300, the area below the arm 312 (and the boom 310) and the front of the bucket 314 are particularly likely to be blind spots. In particular, the human detector may be arranged at a position where the human 200 can be reliably detected in these areas.

In the above embodiment, it has been explained that the smallest distance between the reference point on the outer shape of bucket 314 and person 200 is adopted as distance D. FIG. This assumes that the bucket 314 contacts the person 200 . If there is a possibility that a portion other than bucket 314 will come into contact with person 200, the smallest distance between other points on the outer shape of work machine 300 and person 200 may be adopted as distance D. good. That is, the distance D may be obtained by setting reference points for all of the working devices of the working machine 300 that may come into contact with the person 200 . Alternatively, it is also possible to preliminarily assume portions of the outer shape of work implement 300 that are likely to come into contact with a person, and select reference points from among them. The reference point may be dynamically selected from locations with a high possibility of contact according to the attitude of work implement 300 .

Although the hydraulic excavator 301 is used as an example of the working machine in the above embodiment, the present invention can also be applied to other working machines. For example, by reducing the target operating speed of the work device when the possibility of the work device that performs the work coming into contact with the person 200 increases (the distance D gradually decreases), the above embodiment can be applied to other work machines as well. can have the same effect as

8, 9, 10: Operation lever device (operator)
100: Controllers 101, 102, 103: Inertial measurement device (attitude detector)
104L, 104R, 105L, 105R, 106L, 106R, 107: Camera (human detector)
300: Work machine 301: Hydraulic excavator 310: Boom (work device)
312: Arm (work device)
314: Bucket (work device)

Claims (8)

a working machine,
a work device for performing a work motion;
an attitude detector that detects the attitude of the working device;
a human detector that detects a person existing around the working device;
an operation device for inputting an operation instruction to the working device;
a controller that controls the working device;
with
The controller uses the posture of the work device and the amount of operation of the operation device to estimate the posture of the work device after a predetermined time from when the human detector detects the person,
the controller calculates a distance between the work device and the person after the predetermined time based on the estimated posture of the work device;
The working machine, wherein the controller reduces the operating speed of the working device when the calculated distance is equal to or less than a distance threshold. After reducing the operating speed of the work device, the controller recalculates the distance between the work device and the person,
2. The working machine according to claim 1, wherein when the recalculated distance is equal to or less than the previous calculated value and an operation instruction to the operating device is input, the operating speed of the working device is reduced again. . After reducing the operating speed of the work device, the controller recalculates the distance between the work device and the person,
2. The working machine according to claim 1, wherein when the recalculated distance is greater than the previous calculated value, the reduced operating speed is maintained until no operation instruction is input to the operating device. The human detector is configured to detect the human existing in a detection area around the working device,
When the controller detects the person in the restricted area inside the detection area, the controller performs processing to reduce the operation speed of the work device,
2. The working machine according to claim 1, wherein when the person is detected in an area outside the restricted area, the operation speed of the working device is not reduced. The controller sets a first area as the restricted area when the movable range of the work device is a first range,
5. The work according to claim 4, wherein when the movable range of said working device is a second range larger than said first range, a second area larger than said first area is set as said restricted area. machine. The working device is
boom,
an arm, and a bucket attached to the tip of the arm,
The human detector is
a side surface of the boom, a lower surface of the boom, a side surface of the arm, an upper surface of the arm, a lower surface of the arm, an upper surface of a main body having a cab of the working device, an upper surface of the cab,
At least two of these areas are arranged so that the areas in which the person can be detected overlap each other, and the person can be detected within a predetermined angle range centered on the person detector. 2. The work machine of claim 1, wherein: The working device is
arm,
a bucket attached to the tip of the arm;
with
The human detector is
a space below the arm;
a space in front of the arm and the bucket;
2. The working machine according to claim 1, wherein the working machine is arranged at a position where at least a person can be detected. The controller calculates a distance between two or more reference points on the outline of the work device and the person,
The work according to claim 1, wherein the controller adopts the shortest distance between the two or more reference points and the person as the distance between the work device and the person. machine.

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