JP2024030384A - Work machine safety equipment - Google Patents

Abstract

The present invention provides a safety device for a working machine that can accurately detect objects located around the working machine while reducing processing load. A safety device includes an object detector (60) and a controller (70). The object detector 60 includes a front object detector 60A having a detection range in front of the revolving upper structure 12 and a rear object detector 60B having a detection range behind the revolving upper structure 12. The number of pixels per unit angle of the detector 60A is set to be larger than the number of pixels of the rear object detector 60B. Further, a first monitoring area A1 is set in front of the upper revolving body 12 corresponding to the front object detector 60A, and a first monitoring area A1 is set in the rear of the upper revolving body 12 corresponding to the rear object detector 60B. A second monitoring area A2 having a smaller depth than the first monitoring area when viewed from the body 12 is set. [Selection diagram] Figure 2

Description

The present invention relates to a safety device for a working machine.

2. Description of the Related Art Conventionally, in working machines such as hydraulic excavators, devices are known that perform safety control by detecting objects to be detected that exist around the working machine. The working machine includes a lower traveling body, an upper rotating body rotatably supported by the lower traveling body, and an attachment rotatably supported in the vertical direction by the upper rotating body.

Patent Document 1 discloses a technique in which a plurality of imaging devices are mounted on an upper revolving structure in order to detect objects around a working machine. In this technique, the plurality of imaging devices include a plurality of wide-angle cameras and a plurality of narrow-angle cameras arranged at each of the front, left, right, and rear parts of the revolving upper structure. By arranging narrow-angle cameras in addition to wide-angle cameras in each direction around the revolving superstructure, noise can occur in the images taken by the wide-angle cameras due to the influence of high-brightness light sources such as truck lights. , a decrease in object recognition accuracy is suppressed.

Japanese Patent Application Publication No. 2020-122376

In the technology described in Patent Document 1, in order to detect a target object, the controller needs to process images taken by four wide-angle cameras and four narrow-angle cameras mounted on the upper revolving body. There is a problem that the load increases.

SUMMARY OF THE INVENTION An object of the present invention is to provide a safety device for a working machine that can accurately detect objects located around the working machine while reducing the processing load compared to the conventional technology.

What is provided by the present invention is a safety device for a work machine having a lower body, a pivotable upper body, and a working member extending forwardly from the upper body. The safety device includes a detection unit that is attached to the upper body and can detect objects around the working machine, and a detection unit that detects objects in a monitoring area set around the upper body based on the detection results of the detection unit. A control unit that determines the entry of an object. The detection unit includes a front detection unit having a detection range in front of the upper body, and a rear detection unit having a detection range on the side or rear of the upper body, and has pixels per unit angle of the front detection unit. The number is set to be larger than the number of pixels of the rear detection section. The monitoring area includes a first monitoring area set at the front of the upper body corresponding to the front detection section, and a first monitoring area set at the side or rear of the upper body corresponding to the rear detection section. and a second monitoring area having a smaller depth than the first monitoring area when viewed from above.

According to this configuration, the depth of the first monitoring area corresponding to the front detection section is set larger than the second monitoring area corresponding to the rear detection section, and furthermore, the number of pixels per unit angle of the front detection section is set to be larger than the depth of the first monitoring area corresponding to the front detection section. Since it is set larger than , it is possible to accurately detect objects located around the work member extending forward from the upper main body. Further, compared to a case where the number of pixels per unit angle of the rear detection section is set to be the same as that of the front detection section, the processing load on the control section can be reduced.

In the above configuration, the angle of view of the rear detection section in a cross section perpendicular to the left-right direction of the upper main body may be set larger than the angle of view of the front detection section in the cross section.

According to this configuration, by making the so-called vertical angle of view of the rear detection section larger than that of the front detection section, it is possible to ensure safety in the rear region of the upper body that tends to become a blind spot.

In the above configuration, the number of pixels of the front detection section and the number of pixels of the rear detection section may be the same.

According to this configuration, while the number of pixels of the front detection section and the rear detection section are the same, the angle of view of the front detection section is set relatively small, so the number of pixels per unit angle of the front detection section is larger. Therefore, the accuracy of detecting objects around the work member can be improved.

In the above configuration, the front detection section may have an acute angle of view, and the rear detection section may have an obtuse angle of view.

According to this configuration, it is possible to improve the detection accuracy of objects around the work member by the front detection section, and to maintain safety in the rear region of the upper body, which is likely to become a blind spot, by the rear detection section.

In the above configuration, the center line of the angle of view of the front detection section in the cross section extends downward from the front detection section, and the upper limit angle of the angle of view of the front detection section extends upward from the front detection section. The angle of view of the front detection section and the mounting angle of the front detection section with respect to the upper main body may be set.

According to this configuration, by setting the center line of the front detection section downward, when the object is a person, it becomes easier to detect the foot of the object, and the accuracy of detecting the person can be improved. Furthermore, by setting the upper limit angle of the front detection section upward, it is possible to stably detect a person's head.

In the above configuration, the angle of view of the front detection section in plan view is set smaller than the angle of view of the rear detection section in plan view, and the angle of view of the front detection section and the rear detection section in plan view are set smaller. The angles of view may be set so that they partially overlap.

According to this configuration, by setting the angle of view of the front detection unit to be small in plan view, the number of pixels per unit angle increases, so it is possible to improve the accuracy of detecting objects around the work member. . In particular, even when the upper main body turns relative to the lower main body, it is possible to stably detect an object that enters the first monitoring area as the upper main body turns. Furthermore, since the angle of view of the front detection section and the angle of view of the rear detection section partially overlap, it is possible to prevent blind spots from occurring and to stably detect objects around the work machine.

In the above configuration, when the control unit determines that the object has entered the monitoring area, the control unit determines whether the target object has entered the monitoring area, based on the detection result of at least one of the front detection unit and the rear detection unit. The distance in the front-rear direction and the distance in the left-right direction of the target object are respectively calculated, and the work includes a direction in which the distance between the target object and the work machine becomes smaller due to the movement of the work machine among the front-rear direction and the left-right direction. It may also be something that limits the operation of the machine.

According to this configuration, the collision between the work machine and the target object is stabilized by restricting the movement of the work machine based on the distance component between the target object and the work machine according to the direction of movement of the work machine. can be prevented and safety can be ensured.

In the above configuration, when the control unit determines that the target object has entered the monitoring area, the control unit determines the distance of the target object from the work machine in the front and back direction based on the detection result of the front detection unit. In addition to calculating the distance, a tip distance, which is a distance in the front-rear direction between the upper body and the tip of the working member, is further calculated, and when the object distance is smaller than the tip distance, the operation of the working machine is determined. It may be possible to limit the

According to this configuration, by restricting the operation of the working machine based on the magnitude relationship between the object distance and the tip distance, the operation can be surely restricted when there is a concern about a collision between the object and the work member. However, it is possible to prevent excessive operational restrictions from occurring.

As described above, the present invention provides a safety device for a working machine that can accurately detect objects located around the working machine while reducing the processing load.

1 is a side view showing a hydraulic excavator which is an example of a working machine according to an embodiment of the present invention. FIG. 3 is a plan view of the hydraulic excavator. FIG. 2 is a block diagram showing a hydraulic circuit, a controller, etc. installed in the hydraulic excavator. FIG. 3 is a block diagram showing the main functions of the controller. 1 is a side view showing a vertical angle of view of a camera in a hydraulic excavator which is an example of a working machine according to an embodiment of the present invention. FIG. 3 is a side view of the hydraulic excavator for explaining the vertical angle of view of the camera. FIG. 3 is a side view of the hydraulic excavator for explaining the vertical angle of view of the camera. FIG. 3 is a plan view of the hydraulic excavator for explaining the horizontal angle of view of the camera. FIG. 2 is a plan view showing a positional relationship between a monitoring area of a work machine and a target object according to an embodiment of the present invention. FIG. 2 is a plan view showing a positional relationship between a monitoring area of a work machine and a target object according to an embodiment of the present invention. FIG. 2 is a plan view showing a positional relationship between a monitoring area of a work machine and a target object according to an embodiment of the present invention. FIG. 2 is a plan view showing a positional relationship between a monitoring area of a work machine and a target object according to an embodiment of the present invention.

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

1 and 2 are a side view and a plan view of a hydraulic excavator 1, which is an example of a working machine equipped with a safety device according to an embodiment of the present invention. The hydraulic excavator 1 includes a lower traveling body 10 (lower main body) that can run on the ground G, and an upper rotating body 12 (upper main body) that is mounted on the lower traveling body 10 so as to be able to turn around an axis extending in the vertical direction. ), a work device 14 (work member) mounted on the revolving upper structure 12 so as to extend forward from the revolving upper structure 12, and a work drive device.

The undercarriage body 10 includes a pair of right crawlers 11R and left crawlers 11L arranged on the right and left sides, respectively. Each of the right and left crawlers 11R, 11L operates so that the lower traveling body 10 travels on the ground G.

The upper revolving body 12 includes a revolving frame 16 and a plurality of elements mounted thereon. The plurality of elements include an engine room 17 that accommodates the engine, a cab 18 that is a driver's cabin, and a counterweight 19 that constitutes the rear end of the revolving upper structure 12.

The working device 14 includes a boom 21, an arm 22, and a bucket 24. The boom 21 is supported at the front end of the swing frame 16 so as to be able to rise and fall. The arm 22 is connected to the tip of the boom 21 so as to be rotatable in the vertical direction relative to the boom 21. The bucket 24 is a tip attachment for performing excavation work, etc., and is attached to the tip of the arm 22 so as to be rotatable in the vertical direction with respect to the arm 22. As shown in FIG. 2, the working device 14 has a center line CA extending in the longitudinal direction of the revolving upper structure 12, and is supported by the revolving upper structure 12 so as to be able to rise and fall. The cab 18 is located at the front end of the revolving upper structure 12 and on the left side of the working device 14.

FIG. 3 shows a hydraulic circuit mounted on the hydraulic excavator 1, a plurality of object detectors 60 (detection section), an alarm 62, a display device 64, and a controller 70 (control section). The controller 70 is composed of, for example, a microcomputer, and controls the operation of each element included in the hydraulic circuit. On the other hand, the controller 70 is electrically connected to a plurality of object detectors 60, alarms 62, and display devices 64, and together constitutes a safety device.

The hydraulic circuit includes a pump unit 30, a plurality of hydraulic actuators, a plurality of control valves, an operating device, a plurality of operating valves, and a plurality of pilot pressure sensors.

The pump unit 30 includes a plurality of hydraulic pumps, and the plurality of hydraulic pumps include at least one main pump and a pilot pump. The plurality of hydraulic pumps are connected to an engine (not shown) that is a driving source, and are driven by power output from the engine to discharge hydraulic oil.

Each of the plurality of hydraulic actuators receives hydraulic oil from the pump unit 30 and moves a movable part of the hydraulic excavator, and includes a plurality of working hydraulic cylinders shown in FIG. 1, that is, the boom cylinder 26. , an arm cylinder 27, a bucket cylinder 28, and a swing motor 32, a right travel motor 33, and a left travel motor 34 shown in FIG.

The boom cylinder 26 expands and contracts when supplied with hydraulic oil so as to raise and lower the boom 21 with respect to the upper revolving structure 12 . The arm cylinder 27 expands and contracts when supplied with hydraulic oil so as to rotate the arm 22 with respect to the boom 21 . The bucket cylinder 28 expands and contracts when supplied with hydraulic oil so as to rotate the bucket 24 with respect to the arm 22 .

The swing motor 32 includes a pair of right-hand swing ports and a left-hand swing port, and when hydraulic oil is supplied to one of the right-hand swing ports and left-hand swing ports, the swing motor 32 rotates in the direction corresponding to the port (right-hand swing direction or left turning direction).

The right travel motor 33 includes a pair of right forward port and right reverse port, and by supplying hydraulic oil to one of the right forward port and right reverse port, the right travel motor 33 moves in the direction corresponding to the port (forward direction or reverse direction). It operates to move the right crawler 11R. Similarly, the left travel motor 34 includes a pair of left forward port and left reverse port, and by supplying hydraulic oil to one of the left forward port and left reverse port, the left travel motor 34 is supplied with hydraulic fluid in the direction corresponding to the port (forward direction or left reverse port). It operates to move the left crawler 11L in the reverse direction).

The plurality of control valves are valves that open and close to enable control of the movement of each of the plurality of hydraulic actuators, and include the swing control valve 36, right travel control valve 37, and left travel control valve shown in FIG. Control valve 38 is included.

The swing control valve 36 is interposed between the pump unit 30 and the swing motor 32, and opens and closes to change the direction and flow rate (swivel flow rate) of the hydraulic oil supplied from the pump unit 30 to the swing motor 32. The swing control valve 36 is constituted by a pilot-operated directional switching valve including a right-hand swing pilot port and a left-hand swing pilot port, and when pilot pressure is input to the right-hand swing pilot port, the swing motor 32 rotates to the right. The valve opens to allow hydraulic oil to be supplied to the rotation port at a flow rate (right rotation flow rate) corresponding to the magnitude of the pilot pressure, and conversely, pilot pressure is input to the left rotation pilot port. Then, the valve is opened to allow hydraulic oil to be supplied to the left rotation port of the rotation motor 32 at a flow rate corresponding to the magnitude of the pilot pressure (left rotation flow rate).

The right travel control valve 37 is interposed between the pump unit 30 and the right travel motor 33, and is configured to change the direction and flow rate (right travel flow rate) of hydraulic oil supplied from the pump unit 30 to the right travel motor 33. Opens and closes. The right travel control valve 37 is constituted by a pilot-operated direction switching valve including a right forward pilot port and a right reverse pilot port, and when pilot pressure is input to the right forward pilot port, the right travel control valve 37 causes the right travel motor 33 to move forward to the right. The valve opens to allow hydraulic oil to be supplied to the port at a flow rate (right forward flow rate) corresponding to the magnitude of the pilot pressure, and conversely, when pilot pressure is input to the right reverse pilot port, the right The valve is opened to allow hydraulic oil to be supplied to the right reverse port of the travel motor 33 at a flow rate (right reverse flow rate) corresponding to the magnitude of the pilot pressure.

The left travel control valve 38 is interposed between the pump unit 30 and the left travel motor 34, and is configured to change the direction and flow rate (left travel flow rate) of hydraulic oil supplied from the pump unit 30 to the left travel motor 34. Opens and closes. The left travel control valve 38 is constituted by a pilot-operated direction switching valve including a left forward pilot port and a left reverse pilot port, and when pilot pressure is input to the left forward pilot port, the left travel control valve 38 causes the left travel motor 34 to move forward to the left. The valve opens to allow hydraulic oil to be supplied to the port at a flow rate (left forward flow rate) corresponding to the magnitude of the pilot pressure, and conversely, when pilot pressure is input to the left reverse pilot port, the left The valve is opened to allow hydraulic oil to be supplied to the left reverse port of the travel motor 34 at a flow rate (left reverse flow rate) corresponding to the magnitude of the pilot pressure.

The plurality of control valves also include a boom control valve, an arm control valve, and a bucket control valve (not shown) provided for each of the boom cylinder 26, arm cylinder 27, and bucket cylinder 28, respectively.

The operating device receives an operation for moving the hydraulic excavator and inputs an operating signal to the controller 70, and includes a plurality of operating devices respectively corresponding to the plurality of control valves. Each of the plurality of operating devices is constituted by a so-called remote control valve connected to the pilot pump, and is configured to allow pilot pressure corresponding to an operation applied to the remote control valve to be applied to the corresponding control valve. Open the valve.

The operations given to the operating device include controlled object operations that are subject to safety control. In this embodiment, the plurality of controlled object operations include a turning operation for turning the upper rotating structure 12 with respect to the lower traveling structure 10, and a right traveling operation for moving the right and left crawlers 11R and 11L, respectively. and a left running operation, and the right running operation and left running operation correspond to a running operation that causes the lower traveling body 10 to perform a running operation.

FIG. 3 shows a turning operation device 42, a right travel operation device 43, and a left travel operation device 44 to which the control target operations are respectively given among the plurality of operation devices.

The swing operation device 42 includes a swing lever and a swing pilot valve connected thereto, and the swing pilot valve controls the swing operation given to the swing lever among the right swing and left swing pilot ports of the swing control valve 36. The valve is opened so that a pilot pressure corresponding to the magnitude of the turning operation is supplied to the pilot port corresponding to the direction. The right travel operator 43 includes a right travel lever and a right travel pilot valve connected thereto, and the right travel pilot valve is the right travel lever of the right forward and left forward pilot ports of the right travel control valve 37. The valve is opened so that a pilot pressure corresponding to the magnitude of the right travel operation is supplied to the pilot port corresponding to the direction of the right travel operation applied to the right travel operation. Similarly, the left travel operation device 44 includes a left travel lever and a left travel pilot valve connected thereto, and the left travel pilot valve is connected to the left travel pilot port of the left travel control valve 38 and the left travel pilot port. The valve is opened so that pilot pressure corresponding to the magnitude of the left travel operation is supplied to the pilot port corresponding to the direction of the left travel operation applied to the left travel lever.

The plurality of operating devices include a swing operating device 42, right travel and left travel operating devices 43, 44, and a boom that receives a boom operation for moving the boom 21 and allows supply of pilot pressure to the boom control valve. an arm operator that receives an arm operation to move the arm 22 and allows pilot pressure to be supplied to the arm control valve; and an arm operator that receives a bucket operation to move the bucket 24 and allows the supply of pilot pressure to the bucket control valve. Includes a bucket operator that allows for the supply of pilot pressure. The boom operation, the arm operation, and the bucket operation are all operations for moving the working device 14.

The plurality of operation valves include a swing operation device 42, a right travel operation device 43, a left travel operation device 44, a swing control valve 36, a right travel control valve 37, and a left travel control valve 38 corresponding to these operation devices. The turning pilot pressure and the right and left travel pilot pressures can be limited by the controller 70, respectively. Specifically, each of the plurality of operation valves is constituted by an electromagnetic pressure reducing valve, and the pressure reducing valve limits the pilot pressure to a degree corresponding to a restriction command input to the pressure reducing valve. Each of the pressure reducing valves according to this embodiment is an electromagnetic inverse proportional pressure reducing valve, and the pilot pressure is limited to a greater extent as the restriction command is larger. The pressure reducing valve may be an electromagnetic proportional pressure reducing valve.

Specifically, the plurality of operation valves include a right turn operation valve 46R, a left turn operation valve 46L, a right forward travel operation valve 47F, a right reverse travel operation valve 47B, and a left forward travel operation valve 48F shown in FIG. and a left reverse travel operation valve 48B.

The right rotation operation valve 46R is interposed between the rotation operation device 42 and the right rotation pilot port of the rotation control valve 36, and receives the right rotation pilot pressure input from the rotation operation device 42 to the right rotation pilot port. It operates to limit the right turn at a degree corresponding to the right turn restriction command inputted from the controller 70 to the right turn operation valve 46R. Similarly, the left rotation operation valve 46L is interposed between the rotation operation device 42 and the left rotation pilot port of the rotation control valve 36, and the left rotation pilot pressure is input from the rotation operation device 42 to the left rotation pilot port. is operated to limit the left turn to a degree corresponding to a left turn restriction command inputted from the controller 70 to the left turn operation valve 46L.

The right forward travel operation valve 47F is interposed between the right travel operator 43 and the right forward pilot port of the right travel control valve 37, and is configured to control the right forward pilot input from the right travel operator 43 to the right forward pilot port. It operates to limit the pressure to a degree corresponding to the right forward travel restriction command input from the controller 70 to the right forward travel operation valve 47F. Similarly, the right reverse travel control valve 47R is interposed between the right travel operator 43 and the right reverse pilot port of the right travel control valve 37, and receives input from the right travel operator 43 to the right reverse pilot port. It operates to limit the right reverse pilot pressure to a degree corresponding to the right reverse travel restriction command input from the controller 70 to the right reverse travel operation valve 47R.

The left forward travel operation valve 48F is interposed between the left travel operator 44 and the left forward pilot port of the left travel control valve 38, and controls the left forward pilot input from the left travel operator 44 to the left forward pilot port. It operates to limit the pressure to a degree corresponding to the left forward travel restriction command input from the controller 70 to the left forward travel operation valve 48F. Similarly, the left reverse travel control valve 48R is interposed between the left travel operator 44 and the left reverse pilot port of the left travel control valve 38, and receives input from the left travel operator 44 to the left reverse pilot port. It operates to limit the left reverse pilot pressure to a degree corresponding to the left reverse travel restriction command input from the controller 70 to the left reverse travel operation valve 48R.

Each of the plurality of pilot pressure sensors is an operation amount detector that detects the magnitude (operation amount) of each of the turning operation, the right running operation, and the left running operation. Specifically, each of the plurality of pilot pressure sensors is constituted by a pressure sensor, and detects the pilot pressure input to each of the swing control valve 36, the right travel control valve 37, and the left travel control valve 38, and detects the pilot pressure. A detection signal corresponding to the magnitude of , that is, a detection signal corresponding to the target operation amount is input to the controller 70 . Specifically, the plurality of pilot pressure sensors include a right turn pilot pressure sensor 52R that detects the right turn pilot pressure, a left turn pilot pressure sensor 52L that detects the left turn pilot pressure sensor, and a right turn pilot pressure sensor 52L that detects the left turn pilot pressure sensor. a right forward pilot pressure sensor 53F that detects pilot pressure; a right backward pilot pressure sensor 53B that detects the right backward pilot pressure; a left forward pilot pressure sensor 54F that detects the left forward pilot pressure; and a left backward pilot pressure sensor 54F that detects the left forward pilot pressure. and a left backward pilot pressure sensor 54B that detects the left reverse pilot pressure sensor 54B.

In the hydraulic circuit, the swing motor 32, the swing control valve 36, and the right and left swing operation valves 46R, 46L, together with the pump unit 30, constitute a swing drive circuit for swinging the upper swing structure 12. Similarly, the right travel motor 33, the right travel control valve 37, and the right forward and right reverse travel operation valves 47F, 47B, together with the pump unit 30, constitute a right travel drive circuit for moving the right crawler 11R, and the left travel motor 34, the left travel control valve 38 and the left forward and left reverse travel operation valves 48F and 48B, together with the pump unit 30, constitute a left travel drive circuit for moving the left crawler 11L.

The plurality of object detectors 60 are each arranged at a specific part of the hydraulic excavator, and detect a detection target existing around the hydraulic excavator, and also include a distance from the specific part to the detection target. A detection signal that makes it possible to obtain position information is generated and input to the controller 70. In this embodiment, each of the plurality of object detectors 60 is constituted by an imaging device (camera) such as a monocular camera or a stereo camera, and generates a photographed image including the detection object. Note that in other embodiments, each object detector 60 may be a sensor such as an ultrasonic sensor, an infrared laser, or a millimeter wave radar.

Specifically, the plurality of object detectors 60 (detection units) according to this embodiment are mounted on the upper revolving structure 12 so as to be able to detect objects around the hydraulic excavator 1, and are shown in FIG. It includes a front object detector 60A (front detection section), a right object detector 60R (rear detection section), a left object detector 60L (rear detection section), and a rear object detector 60B (back detection section). The front object detector 60A is arranged at the right front end of the revolving upper structure 12 so as to be able to detect an object located in front of the revolving upper structure 12. The right object detector 60R is arranged on the right side of the upper revolving structure 12 so as to be able to detect at least a detection object located on the right side of the upper revolving structure 12, and the left object detector 60L is disposed on the left side of the upper revolving body 12 so as to be able to detect at least a detection target located on the left side of the upper revolving body 12, and the rear object detector 60B is located at least on the left side of the upper revolving body 12. It is arranged at the rear end of the upper revolving body 12 so as to be able to detect a detection target located behind the upper revolving body 12 . In other words, regarding the object detector 60, the front object detector 60A has a detection range in front of the revolving upper structure 12. The rear object detector 60B, the left object detector 60L, and the right object detector 60R have a detection range on the side or rear of the upper revolving structure 12.

The alarm device 62 issues an alarm when an alarm command is input from the controller 70. The alarm device 62 may be an audible alarm, such as a buzzer, or a light alarm, such as an alarm lamp.

The display device 64 has a screen capable of displaying a peripheral image including the object to be detected, and is arranged in the cab 18 so that the screen can be viewed by the operator. The display device 64 displays an image corresponding to a display command signal input from the controller 70.

The controller 70 identifies the presence or absence of a detection target in the vicinity of the hydraulic excavator 1 based on image signals input from each of the target object detectors 60A, 60R, 60L, and 60B, and detects the presence or absence of a detection target in the vicinity of the hydraulic excavator 1. When entering the area, predetermined safety control is executed.

The safety control includes speed limit control, alarm control, and display control. The speed limit control is a control that limits (decelerates) the speed of a preset limited operation among the operations of the hydraulic excavator 1 according to the detected distance, and controls to set the speed to 0, that is, the speed of the limited operation It may also include stop control for forcibly stopping the operation. In the present embodiment, the restricted operation includes at least the turning operation of the upper rotating structure 12 relative to the lower traveling structure 10, and also includes the traveling operation by the right crawler 11R and the left crawler 11L depending on the situation. Alternatively, the restricted motions may include motions of the working device 14, such as a raising and lowering motion of the boom 21 and a rotating motion of the arm 22. The alarm control is control that causes the alarm device 62 to issue the alarm based on the detection of the detection target. The display control is control for displaying a warning image on the display device 64 based on the detection of the detection target. The warning image is, for example, an image taken by each of the object detectors 60A, 60R, 60L, and 60B, and is a peripheral image including the detection object.

The controller 70 determines whether an object to be detected enters a monitoring area set around the upper revolving structure 12, which will be described later, based on the detection result of the object detector 60, and performs various safety controls according to the determination result. Execute. The controller 70 includes a plurality of functions as shown in FIG. 4 in order to execute safety control, and the plurality of functions include a position information generation section 72, a safety control determination section 74, a turning limit command section 76, and a travel limit command section 76. It includes a command section 78, an alarm command section 82, and a display command section 84. These functions are realized, for example, by a CPU included in the controller 70 executing a program stored in advance in a memory included in the controller 70.

The position information generation unit 72 periodically captures image signals input from each of the target object detectors 60A, 60R, 60L, and 60B (specifically, each time a preset sampling period elapses), and By processing the image signal, it is possible to determine the presence or absence of a detection target within the photographing range of the target object detectors 60A, 60R, 60L, and 60B, and to determine the criteria for the detection target when the detection target exists. A distance value corresponding to the distance from the position (in this embodiment, the position where each of the object detectors 60A, 60R, 60L, and 60B are arranged), that is, the detection distance, is specified, and the position of the detection object is determined. and generating position information including the distance value. That is, the position information generation unit 72 constitutes a position information acquisition unit that periodically acquires position information together with the object detectors 60A, 60R, 60L, and 60B. The object to be detected preferably includes at least a person (worker), and may include an object other than a person.

The safety control determining unit 74 determines whether safety control is necessary and the content of the safety control based on the position information generated by the position information generating unit 72. Specifically, when the safety control determination unit 74 according to this embodiment determines that safety control is necessary, it specifies the motion whose speed should be restricted, and also determines the speed of the motion to be restricted corresponding to the detection distance. determine the degree of restriction. Speed limits also include forced stops.

The turning restriction command section 76 generates a turning restriction command signal. The turning restriction command signal is a signal for executing turning restriction control among the safety controls determined by the safety control determination unit 74, and specifically limits the speed of right turning operation or left turning operation. This is a signal for limiting the speed (including forced stop) by the degree of restriction determined for limiting the speed (turning speed) when control is specified. The rotation restriction command unit 76 commands the operation valve corresponding to the restricted operation (the right rotation operation valve 46R when the right rotation operation is restricted) among the right rotation operation valve 46R and the left rotation operation valve 46L. The turning limit command signal is input.

Travel restriction command section 78 generates a travel restriction command signal. The travel restriction command signal is a signal for executing travel restriction control among the safety controls determined by the safety control determination unit 74, and specifically, a control that limits the speed of forward travel operation or reverse travel operation. This is a signal for limiting the speed (including forced stop) by the degree of restriction determined for the restriction of the speed (traveling speed) when the speed is specified. The travel restriction command unit 78 controls the operation valve (reverse) corresponding to the restricted operation to be restricted among the right forward travel operation valve 47F, the right reverse travel operation valve 47B, the left forward travel operation valve 48F, and the left reverse travel operation valve 48B. When the travel operation is restricted, the turning restriction command signal is input to the right reverse travel operation valve 47B and the left forward travel operation valve 48B.

The alarm command unit 82 generates an alarm command signal when the safety control determination unit 74 determines that safety control is necessary, and issues an alarm to the alarm device 62 by inputting the alarm command signal to the alarm device 62. let

The display command unit 84 generates a display command signal when the safety control determination unit 74 determines that safety control is necessary, and inputs the display command signal to the display device 64 to display the warning image on the display device 64. Display.

Referring to FIG. 2, in this embodiment, a plurality of monitoring areas are set around the upper revolving structure 12 as a reference. Specifically, the monitoring area includes a first stopping area A1 (first monitoring area), a second stopping area A2 (second monitoring area), a first deceleration area B1 (first monitoring area), and a second stopping area A1 (first monitoring area). It includes a deceleration area B2 (second monitoring area) and a third deceleration area B3 (second monitoring area). Note that the monitoring area shown in FIG. 2 is set when the revolving upper structure 12 performs a turning operation.

The first stop area A1 is set to extend along the working device 14 on the right side of the revolving upper structure 12. In this embodiment, the first stop area A1 has a trapezoidal shape that extends long in the front-rear direction when viewed from above. The first stop area A1 includes a first outer edge A1R and a first inner edge A1L. The first outer edge A1R defines the outer (right) side of the first stop area A1 and extends in the front-rear direction of the upper revolving structure 12. Similarly, the first inner edge A1L defines the inner (left) side of the first stop area A1 and extends in the front-rear direction of the revolving upper structure 12. When the front object detector 60A detects that the object to be detected has entered the first stop area A1, the controller 70 at least drives the working device 14, rotates the upper rotating structure 12 to the right, and controls the lower traveling structure. Forcibly stop the forward movement of step 10. The length of the first stop area A1 in the front-rear direction is set so that the first stop area A1 includes the area adjacent to the left and right sides of the tip (bucket 24) of the work device 14 (maximum reach of the work device 14). range).

As shown in FIG. 2, the second stop area A2 is formed on both left and right sides and at the rear of the upper rotating body 12, and has a U-shape in plan view. The second stop area A2 includes a rear stop area A21 behind the revolving upper structure 12, a left stop area A22 to the left of the revolving upper structure 12, and a right stop area A23 to the right of the revolving upper structure 12. When the rear object detector 60B, the right object detector 60R, and the left object detector 60L detect that the object to be detected has entered the second stop area A2, the controller 70 at least The left and right turning operations and the backward movement of the lower traveling body 10 are forcibly stopped.

The first deceleration region B1 is arranged on the opposite side of the working device 14 when viewed from the first stop region A1 in a plan view, and is arranged so as to be in contact with the first stop region A1 with the first outer edge A1R as a boundary. The first deceleration region B1 has a trapezoidal shape that extends long in the front-rear direction when viewed from above. The first deceleration region B1 includes a second outer edge B1R and a second inner edge B1L. The second outer edge B1R defines the outer (right) side part of the first deceleration region B1, and extends in the front-rear direction of the upper revolving structure 12. Similarly, the second inner edge B1L defines the inner (left) side of the first deceleration region B1 and extends in the front-rear direction of the upper revolving structure 12. When the front object detector 60A detects that the detection object has entered the first deceleration region B1, the controller 70 decelerates at least the right turning operation of the upper revolving structure 12. The length of the first deceleration region B1 in the front-rear direction is set so that the first deceleration region B1 includes a region adjacent to the left and right sides of the tip (bucket 24) of the working device 14. Note that when the posture of the working device 14 changes, the controller 70 changes the lengths of the first stop area A1 and the first deceleration area B1 according to the position of the tip of the working device 14. Good too.

As shown in FIG. 2, the second deceleration area B2 and the third deceleration area B3 are arranged on the left and right outer sides of the left stop area A22 and the right stop area A23. When the left object detector 60L or the right object detector 60R detects that the object to be detected has entered the second deceleration region B2 or the third deceleration region B3, the controller 70 at least Decelerate left and right turning movements.

FIG. 5 is a side view showing the angle of view of the front object detector 60A and the rear object detector 60B (camera) in the hydraulic excavator 1 according to the present embodiment. In FIG. 5, the angle of view FA of each camera is illustrated by two solid lines. Moreover, the central axis CL of the angle of view FA is illustrated by a dashed dotted line. Further, the numbers shown on the ground represent the distances from each camera in the front-rear direction (horizontal direction). In this embodiment, the central axes CL of both the front object detector 60A and the rear object detector 60B are set downward from each detector. Furthermore, the number of pixels of the cameras of the front object detector 60A and the rear object detector 60B is the same.

Table 1 shows the number of pixels per predetermined angle of the front object detector 60A (front detection section) and the rear object detector 60B (back detection section).

図２に示すように、第１停止領域Ａ１の奥行き（上部旋回体１２から離れる方向における幅）が第２停止領域Ａ２の奥行きよりも大きい場合に、例えば上記２つのカメラの解像度（画素数）が同一の１０８０Ｐｘ（１９２０×１０８０＝約２００万画素）であると、後対象物検知器６０Ｂの画角を広く、前対象物検知器６０Ａの画角を狭くすることで、単位角度（１度）当たりの各検知器の画素数は、表１のようになる。すなわち、前対象物検知器６０Ａの単位角度あたりの画素数は、後対象物検知器６０Ｂの前記画素数よりも大きく設定されている。また、一例として、前対象物検知器６０Ａの垂直画角（上部旋回体１２の左右方向と直交する断面における画角）は７０度（鋭角）であり、後対象物検知器６０Ｂの垂直画角は１２０度（鈍角）である。すなわち、後対象物検知器６０Ｂの垂直画角が、前対象物検知器６０Ａの垂直画角よりも大きく設定されている。

As shown in FIG. 2, when the depth of the first stop area A1 (width in the direction away from the rotating upper structure 12) is greater than the depth of the second stop area A2, for example, the resolution (number of pixels) of the two cameras is the same 1080Px (1920 x 1080 = approximately 2 million pixels), by widening the angle of view of the rear object detector 60B and narrowing the angle of view of the front object detector 60A, the unit angle (1 degree The number of pixels of each detector per ) is as shown in Table 1. That is, the number of pixels per unit angle of the front object detector 60A is set to be larger than the number of pixels of the rear object detector 60B. Further, as an example, the vertical angle of view of the front object detector 60A (the angle of view in a cross section perpendicular to the left-right direction of the upper rotating body 12) is 70 degrees (acute angle), and the vertical angle of view of the rear object detector 60B is 70 degrees (acute angle). is 120 degrees (obtuse angle). That is, the vertical angle of view of the rear object detector 60B is set to be larger than the vertical angle of view of the front object detector 60A.

表２では、前対象物検知器６０Ａおよび後対象物検知器６０Ｂの、図５に示す各距離間での画素数を示しており、１度当たりの画素数が大きいほど遠距離での画素差が大きくなるため、より人の検知性能が高くなり、結果として測距精度も向上する。そして、図２に示すように、上部旋回体１２の側方または後方では、監視領域の奥行きを狭くし、上部旋回体１２の前方では監視領域の左右幅を狭くすることで、対象物（人）を検知するための監視領域が小さくなるように最適化している。この結果、コントローラ７０の処理負荷を低減し、処理速度の低下を防ぐことで、油圧ショベル１の制御を迅速に行うことで安全性を確保することができる。なお、表２における角度差は、図５に示すように各カメラ（焦点位置）と当該カメラから１ｍ間隔の位置とを結ぶ直線同士の角度差を意味し、１度当たりの画素数と前記角度差との積によって、１ｍ区間ごとの画素数を算出することができる。 Table 2 shows the number of pixels between each distance between the front object detector 60A and the rear object detector 60B. As an example, the angular difference α from the distance of 5 m to 6 m of the front object detector 60A is 6 degrees.

Table 2 shows the number of pixels of the front object detector 60A and the rear object detector 60B at each distance shown in FIG. Since this becomes larger, the human detection performance becomes higher, and as a result, the distance measurement accuracy also improves. As shown in FIG. 2, the depth of the monitoring area is narrowed on the side or rear of the revolving upper structure 12, and the left and right width of the monitoring area is narrowed in front of the revolving upper structure 12. ) is optimized so that the monitoring area for detecting is small. As a result, by reducing the processing load on the controller 70 and preventing a decrease in processing speed, safety can be ensured by quickly controlling the hydraulic excavator 1. In addition, the angular difference in Table 2 means the angular difference between straight lines connecting each camera (focal position) and a position 1 m apart from the camera as shown in FIG. 5, and the number of pixels per degree and the angle The number of pixels per 1 m section can be calculated by multiplying by the difference.

6 and 7 are side views of the hydraulic excavator 1 for explaining the vertical angle of view of the camera of the front object detector 60A. In this embodiment, as shown in FIG. 6, the central axis CL (center line, optical axis) of the angle of view of the front object detector 60A in the cross section perpendicular to the left-right direction of the upper revolving body 12 is The angle of view of the front object detector 60A and the angle of view in front of the upper rotating body 12 extend downward from the front object detector 60A, and the upper limit angle of the angle of view of the front object detector 60A extends upward from the front object detector 60A. The mounting angle of the target object detector 60A is set.

In this way, by setting the center axis CL of the front object detector 60A downward from the horizontal line, the foot position of the person H who is close to the hydraulic excavator 1 is reflected in the photographed image of the front object detector 60A. It becomes easier. In addition, in FIG. 6, the person H placed near the upper revolving structure 12 and the lower traveling structure 10 are shown in an overlapping state, but in such a case, when the upper revolving structure 12 turns, There is a possibility that the work device 14 and the person H will collide. Therefore, as shown in FIG. 6, by setting the central axis CL of the front object detector 60A downward, the person H (the person H on the rear side in FIG. 6) who is close to the angle of view FA can be detected. be able to.

As shown in FIG. 7, the upper limit angle (upper end) of the angle of view FA of the front object detector 60A may be directed downwards from the horizon, but in this case, the head of the person H in the distance will not be reflected, and the person Detection rate may decrease. For this reason, as shown in FIG. 6, it is more desirable that the upper limit angle of the angle of view FA is set above the horizontal line.

Further, as described above, a monocular camera may be used as the object detector 60 typified by the front object detector 60A, but in this case, the distance from each detector to the person is determined by the position of the person's feet. It is calculated from a preset body size. In this case as well, as shown in FIG. 6, it is desirable to increase the probability that the whole body of the person H will be reflected within the angle of view FA by appropriately setting the angle of view of the front object detector 60A.

FIG. 8 is a side view of the hydraulic excavator 1 for explaining the horizontal viewing angle of the camera of the object detector 60. In this embodiment, as shown by arrows in FIG. 8, the angle of view of the front object detector 60A in plan view is the same as that of the rear object detector 60B, left object detector 60L, and right object detector in plan view. The angle of view is set smaller than each angle of view of 60R. Furthermore, the angle of view of the front object detector 60A and the angle of view of the right object detector 60R (rear detection section) are set to partially overlap in plan view.

In the area in front of the revolving upper structure 12, in addition to cases in which a person approaches the revolving upper structure 12 by themselves (for example, toward the rotation center axis of the revolving upper structure 12), when the revolving upper structure 12 rotates, the work equipment is 14 must also be considered. In this case, the person approaches the working device 14 not toward the central axis of rotation of the revolving upper structure 12 but along the left-right direction of the revolving upper structure 12 .

In order to increase the detection accuracy (distance measurement accuracy) of a person approaching the upper revolving structure 12 as in the former case, increase the number of pixels per unit angle of the front object detector 60A in the cross section as shown in FIG. On the other hand, in order to accurately detect the approach to the working device 14 when the upper revolving structure 12 is turning, as in the latter case, it is desirable to increase the number of pixels per unit angle of the front object detector 60A in plan view. is desirable.

9 to 12 are plan views showing the positional relationship between the monitoring area of the hydraulic excavator 1 and a target object according to the present embodiment. In this embodiment, when the controller 70 determines that the object has entered the monitoring area, the controller 70 activates the front object detector 60A, the rear object detector 60B, the left object detector 60L, and the right object detector 60R. Based on at least one of the detection results, the distance in the front-rear direction and the distance in the left-right direction of the object with respect to the hydraulic excavator 1 are respectively calculated. The direction is based on the upper revolving body 12. Then, the controller 70 limits the operation of the hydraulic excavator 1 including the direction in which the distance between the object and the hydraulic excavator 1 becomes smaller due to the movement of the hydraulic excavator 1 among the longitudinal direction and the horizontal direction.

Specifically, as shown in FIG. 9, when the person H is located on the right side of the working device 14, if the lower traveling body 10 of the hydraulic excavator 1 moves forward, the distance between the person H and the hydraulic excavator 1 in the front-rear direction will change. becomes smaller. Therefore, the controller 70 can prevent contact and collision between the person H and the hydraulic excavator 1 by restricting the forward motion of the lower traveling body 10. Although FIG. 9 shows a case where the first deceleration area B1 is set at the tip of the first stop area A1, the same applies to the positional relationship of each area shown in FIG. 2.

On the other hand, as shown in FIG. 10, it is assumed that the person H is located on the right side of the working device 14 and further to the right side of the first stop area A1 and the first deceleration area B1. Even if the lower traveling body 10 moves forward in this state, the hydraulic excavator 1 and the person H do not come into contact with each other. However, when the upper revolving body 12 turns clockwise from the state shown in FIG. 10, the person H enters the first deceleration area B1 and the first stop area A1 in order, and there is a concern that the work equipment 14 and the person H may come into contact soon. Ru. Therefore, the controller 70 prevents contact and collision between the person H and the hydraulic excavator 1 by restricting the right turning operation of the upper revolving structure 12. As described above, when the hydraulic excavator 1 approaches a target object by the traveling operation of the lower traveling body 10, the hydraulic excavator 1 approaches the target object by the turning operation of the upper rotating body 12 based on the distance in the longitudinal direction. When approaching a target object, the movement of the hydraulic excavator 1 is restricted based on the distance in the left and right directions, thereby preventing a collision between the hydraulic excavator 1 and the object and ensuring safety. That is, the controller 70 limits the movement of the hydraulic excavator 1 based on the distance component between the object and the hydraulic excavator 1 according to the direction of movement of the hydraulic excavator 1, and prevents a collision between the hydraulic excavator 1 and the object. can be stably prevented.

Furthermore, in the present embodiment, when the controller 70 determines that the object has entered the monitoring area, the controller 70 detects the object, which is the distance of the object in the longitudinal direction with respect to the hydraulic excavator 1, based on the detection result of the front object detector 60A. In addition to calculating the object distance, the tip distance, which is the distance in the front-rear direction between the upper revolving body 12 and the tip of the working device 14, is further calculated. Then, the controller 70 limits the operation of the hydraulic excavator 1 when the object distance is smaller than the tip distance. Specifically, as shown in FIG. 11, the distance in the longitudinal direction between the revolving upper structure 12 and the person H (object distance) is longer than the distance in the longitudinal direction between the revolving upper structure 12 and the bucket 24 (tip distance). If it is large, the working device 14 and the person H will not come into contact even if the upper revolving body 12 performs a right-turning operation. Therefore, in this case, the controller 70 does not limit the right turning operation of the revolving upper structure 12.

On the other hand, as shown in FIG. 12, when the distance in the longitudinal direction between the revolving upper structure 12 and the person H (object distance) is smaller than the distance in the longitudinal direction between the revolving upper structure 12 and the bucket 24 (tip distance) If the upper revolving structure 12 performs a right-turning operation, there is a concern that the working device 14 and the person H may come into contact with each other. Therefore, in this case, the controller 70 only needs to limit the right turning operation of the upper revolving structure 12. By performing the control shown in FIGS. 11 and 12, based on the magnitude relationship between the object distance and the tip distance, only when there is a concern about contact between the hydraulic excavator 1 (work device 14) and the person H. Since the operation of the hydraulic excavator 1 can be restricted by using the hydraulic excavator 1, unnecessary and excessive restriction of the operation can be prevented and the operability of the hydraulic excavator 1 can be prevented from deteriorating.

As described above, in this embodiment, the depth (the length in the front-rear direction in FIG. 2) of the first stop area A1 or the second deceleration area B2 (both are the first monitoring areas) corresponding to the front object detector 60A is set larger than the depth (the length in the front-rear direction in FIG. 2) of the rear stop area A21 (second monitoring area) of the second stop area A2 corresponding to the rear object detector 60B. Further, the number of pixels per unit angle of the front object detector 60A is set to be larger than the number of pixels per unit angle of the rear object detector 60B. Therefore, objects located around the working device 14 extending forward from the upper revolving structure 12 can be detected with high accuracy. Further, the processing load on the controller 70 can be reduced compared to the case where the number of pixels per unit angle of the rear object detector 60B is set to be the same as that of the front object detector 60A.

In particular, the peripheral speed of the working device 14 that protrudes forward from the revolving upper structure 12 becomes higher than that of the revolving upper structure 12 when the revolving upper structure 12 turns. Therefore, in order to prevent a collision between the work device 14 and an object located around the work device 14, it is necessary to detect the object with particularly high accuracy. In this embodiment, as shown in FIG. 2, the front object It is also necessary to ensure high detection accuracy of the object detector 60A up to the tip of the working device 14. For this reason, the number of pixels per unit angle of the front object detector 60A is set to be larger than that of the rear object detector 60B. On the other hand, if the number of pixels per unit angle of the rear detection section represented by the rear object detector 60B is set to be the same as that of the front object detector 60A, the processing load on the controller 70 will increase. The number is set relatively small. On the sides and rear of the revolving upper structure 12, there are no longer protruding members such as the working device 14 compared to the front, so the depth of the monitoring area can be set smaller as shown in FIG. 2. Utilizing this point, it becomes possible to relatively reduce the number of pixels in the rear detection section.

Furthermore, in this embodiment, by making the so-called vertical angle of view of the rear object detector 60B larger than that of the front object detector 60A, it is possible to ensure safety in the rear region of the upper rotating structure 12, which is likely to become a blind spot. can. In particular, as shown in FIG. 5, it is difficult for the operator inside the cab 18 to see the area directly below the rear end of the revolving upper structure 12. Therefore, as shown in FIG. 5, the vertical angle of view of the rear object detector 60B is set to be large, and by including the hard-to-see area in the detection range as described above, safety at the rear of the upper rotating structure 12 can be improved. is also maintained high.

Furthermore, in this embodiment, while the number of pixels of each of the front object detector 60A and the rear object detector 60B is the same, the vertical angle of view of the front object detector 60A is set to be relatively small. , the number of pixels per unit angle of the front object detector 60A becomes larger, and the accuracy of detecting objects around the working device 14 can be further improved.

Furthermore, as described above, the vertical angle of view of the front object detector 60A is an acute angle, and the vertical angle of view of the rear object detector 60B is an obtuse angle. The rear object detector 60B can improve the accuracy of detecting objects in the rear object detector 60B, and stably maintain safety in the rear region of the upper revolving structure 12, which tends to become a blind spot.

In addition, in this embodiment, as shown in FIG. 5, by setting the center axis CL of the front object detector 60A downward, when the object is a person, it becomes easier to capture the feet of the object, and the detection of the person is made easier. Accuracy can be increased. Furthermore, by setting the upper limit angle of the front object detector 60A upward, it is possible to stably detect a person's head.

Furthermore, in this embodiment, as shown in FIG. 8, the angle of view (horizontal angle of view) in plan view of the front object detector 60A is set relatively small, so that the number of pixels per unit angle is set to be relatively small. Since it is larger, the accuracy of detecting objects around the working device 14 can be further improved. In particular, even when the upper rotating body 12 turns with respect to the lower traveling body 10, it is possible to stably detect an object that enters the first stop area A1 and the first deceleration area B1 due to the turning. Can be done. In addition, since the horizontal angle of view of the front object detector 60A and the vertical angle of view of the right object detector 60R partially overlap, further blind spots are prevented from occurring and objects around the hydraulic excavator 1 can be detected. It can be detected stably.

The present invention is not limited to each embodiment described above. The present invention includes, for example, the following aspects.

The positional information for detecting the target detection object may be information about the relative position of the detection target with respect to the reference position set for the working machine, and only information about the distance of the detection target from the reference position may be used. or may include other information. For example, a turning angle sensor that detects the turning angle of the upper rotating structure 12 with respect to the lower traveling structure 10 may be provided, and the position coordinates of the object to be detected may be specified based on the turning angle detected by the turning angle sensor.

Further, the reference position does not necessarily have to be the installation position of the object detector (that is, the distance does not have to be the distance from the object detector to the object to be detected), and may be other parts of the working machine. , or a location set around the work machine. For example, a portion of the working machine closest to the detection target may be specified based on a detection signal generated by a target object detector, and the position of the portion may be set as the reference position. That is, the reference position may be set so that the shortest distance is always calculated as the distance.

Furthermore, the object detector according to the present invention is not limited to one that includes an imaging device. For example, if there is no particular limitation on the object to be detected (that is, if there is no need to specify the object to be detected), the object detector may be a distance detector such as an infrared depth sensor or a millimeter wave radar. Alternatively, instead of a monocular camera, it may be an imaging device capable of generating three-dimensional information, such as a stereo camera.

When speed limit control is executed in the present invention, the specific means for executing the speed limit control is not limited. For example, the swing operation device 42 and the traveling operation devices 43 and 44 are electric lever devices, that is, devices that generate electric signals corresponding to operations input by the operator and input them to the controller, and the controller is based on the electric signals. In a work machine configured to operate a solenoid valve interposed between a pilot hydraulic pressure source and a control valve (for example, the swing control valve 36 and the traveling control valves 37 and 38), the input power to the solenoid valve is The speed limitation (that is, reducing the actual speed below the speed corresponding to the operation) may be performed by changing the command.

In the above embodiment, the operation of the hydraulic excavator 1 is forcibly stopped in the first stop area A1, but when an object is confirmed in the first stop area A1, the above-mentioned alarm etc. are issued. It can be anything. Furthermore, each of the deceleration regions B1 to B3 does not need to be set.

Further, in the above embodiment, the explanation has been made based on the relationship between the front object detector 60A as the front detection section and the rear object detector 60B as the rear detection section. The same applies to the relationship between the left object detector 60R or the left object detector 60L and the front object detector 60A. Note that the object detector 60 may include at least one of the rear object detector 60B, the left object detector 60L, and the right object detector 60R, and in particular, the left object detector 60L and the right object detector 60R. The right object detector 60R may not be provided.

Furthermore, in the above embodiment, when the revolving upper structure 12 performs a turning operation, a monitoring area as shown in FIG. 2 is set around the revolving upper structure 12 as a reference. The present invention is not limited to this. In FIG. 2, an arcuate deceleration area may be further set on the rear side of the rear stop area A21 of the second stop area A2. Both left and right ends of the deceleration area may be connected to the second deceleration area B2 and the third deceleration area B3, respectively.

1 Hydraulic excavator (work machine)
10 Lower traveling body (lower main body)
12 Upper revolving body (upper body)
14 Working device 60 Object detector 60A Front object detector (detection section, front detection section)
60B Rear object detector (detection section, rear detection section)
60R Right object detector (detection section, rear detection section)
60L Left object detector (detection section, rear detection section)
70 Controller (control unit)
A1 1st stop area (1st monitoring area)
A2 Second stop area (second monitoring area)
CL Center axis FA Angle of view

Claims (8)

A safety device for a working machine having a lower body, a pivotable upper body, and a working member extending forward from the upper body,
a detection unit attached to the upper body and capable of detecting objects around the working machine;
a control unit that determines entry of an object into a monitoring area set around the upper main body based on the detection result of the detection unit;
The detection unit includes a front detection unit having a detection range in front of the upper body, and a rear detection unit having a detection range on the side or rear of the upper body, and has pixels per unit angle of the front detection unit. the number is set larger than the number of pixels of the rear detection section,
The monitoring area includes a first monitoring area set at the front of the upper body corresponding to the front detection section, and a first monitoring area set at the side or rear of the upper body corresponding to the rear detection section. and a second monitoring area having a depth smaller than the first monitoring area when viewed from above. The safety device for a working machine according to claim 1, wherein the angle of view of the rear detection section in a cross section perpendicular to the left-right direction of the upper body is set to be larger than the angle of view of the front detection section in the cross section. The safety device for a working machine according to claim 2, wherein the number of pixels of the front detection section and the number of pixels of the rear detection section are the same. The safety device for a working machine according to claim 2, wherein the front detection section has an acute angle of view, and the rear detection section has an obtuse angle of view. The front detection section is configured such that the center line of the angle of view of the front detection section in the cross section extends downward from the front detection section, and the upper limit angle of the angle of view of the front detection section extends upward from the front detection section. The safety device for a working machine according to claim 2, wherein an angle of view of and a mounting angle of the front detection section with respect to the upper body are set. The angle of view of the front detection unit in plan view is set smaller than the angle of view of the rear detection unit in plan view,
The safety device for a working machine according to any one of claims 1 to 5, wherein the angle of view of the front detection unit and the angle of view of the rear detection unit in plan view are set to partially overlap. When the control unit determines that the object has entered the monitoring area, the control unit determines the direction of the object in the front-rear direction with respect to the work machine based on the detection result of at least one of the front detection unit and the rear detection unit. and the distance in the left-right direction, and restrict the operation of the working machine including the direction in which the distance between the object and the working machine becomes smaller due to the movement of the working machine, among the forward-backward direction and the left-right direction. The safety device for a working machine according to any one of claims 1 to 5. When the control unit determines that the object has entered the monitoring area, the control unit calculates an object distance that is a distance of the object in the front and back direction with respect to the work machine based on the detection result of the front detection unit. , further calculating a tip distance that is a distance in the front-rear direction between the upper body and the tip of the working member, and restricting the operation of the working machine when the object distance is smaller than the tip distance. A safety device for a working machine according to any one of items 1 to 5.

Images