JP7141991B2 - excavator - Google Patents

Description

The present invention relates to a hydraulic excavator for excavating and loading operations.

A hydraulic excavator includes a traveling body, a revolving body provided on the upper side of the running body so as to be able to turn, and a working device connected to the revolving body. The work device includes, for example, a boom rotatably connected to the front portion of the revolving body, an arm rotatably connected to the tip of the boom, and a bucket rotatably connected to the tip of the arm. and The boom, arm, and bucket are rotated by driving the boom cylinder, arm cylinder, and bucket cylinder, respectively.

In addition, the hydraulic excavator has a hydraulic pump driven by a prime mover (more specifically, an engine or an electric motor), and a hydraulic pilot system that controls the flow of pressurized oil from the hydraulic pump to the boom cylinder, the arm cylinder, and the bucket cylinder. boom control valve, arm control valve, and bucket control valve.

Patent Literature 1 discloses a device that limits the movement of a working device of a hydraulic excavator in order to avoid collisions between the working device and surrounding obstacles. This device consists of a controller, a pair of electromagnetic proportional valves that generate pilot pressure (hydraulic pressure) according to the command current from the controller and output it to the boom control valve, and a pilot pressure that generates the pilot pressure according to the command current from the controller. and a pair of electromagnetic proportional valves for generating a pilot pressure according to a command current from the controller and outputting it to the bucket control valve.

The controller has a first function of calculating the position of the work implement based on the boom angle, the arm angle, and the bucket angle, and a second function of setting the danger zone of the work implement using the position of the work implement when the monitor switch is operated. 2 function, a third function for setting the restricted area of the working equipment based on the dangerous area of the working equipment, and the above command current to limit the speed of the working equipment when the working equipment is in the restricted area. It has a fourth function of limiting. To explain the fourth function in detail, the controller determines the relationship between the position and speed of the working device, and determines the deceleration pattern in which the speed of the working device decreases as the working device approaches the danger zone and finally reaches zero. is stored, and the speed of the working device is limited according to this deceleration pattern when the working device approaches a dangerous area.

Japanese Patent No. 3215502

By the way, a hydraulic excavator excavates earth and sand with a bucket and loads the excavated material in the bucket. Then, the excavated material is loaded from the bucket onto the platform of the transport vehicle. In this loading operation, when the revolving body revolves, there is a possibility that the bucket and the loading platform of the transport vehicle collide. Therefore, in order to avoid collision between the bucket and the platform of the transport vehicle, a case is assumed in which the technique described in Patent Document 1 is applied to limit the turning of the revolving body.

In this case, the restricted area consists of a deceleration area for decelerating the turning of the revolving body and a stop area for stopping the revolving of the revolving body. Then, as in the technique described in Patent Document 1, if the range of the deceleration region and the range of the stop region are fixed, the turning stop angle when the turning speed of the turning body is maximum (specifically, the turning stop angle of the turning body It is necessary to set the range of the stop region to be large in consideration of the turning angle required from the start of control to stop turning to the actual stop. However, if the revolving speed of the revolving body is actually low, the revolving of the revolving body will be excessively stopped. Therefore, work efficiency is lowered.

SUMMARY OF THE INVENTION An object of the present invention is to provide a hydraulic excavator capable of avoiding a collision between a bucket and a loading platform of a transport vehicle while preventing a decrease in work efficiency.

In order to achieve the above object, a typical present invention provides a work device having a travelable traveling body, a revolving body rotatably provided above the traveling body, and a bucket connected to the revolving body. and a turning angle sensor for detecting the turning angle of the turning body with respect to the traveling body, and an attitude detector for detecting the attitude of the working device, wherein the loading position of the excavated material is set. an excavation position setting device for setting an excavation position of the bucket; a turning angle of the turning body detected by the turning angle sensor; and an attitude of the working device detected by the attitude detector. a controller that calculates the position of the bucket and controls the swinging speed of the swing body according to the position of the bucket, wherein the controller stops swinging based on the loading position and the excavating position. A swing restriction region consisting of a region and a swing deceleration region is set, and when the position of the bucket is in the swing deceleration region, the swing of the swing body is decelerated, and the bucket is in the swing stop region. In this case, the turning of the turning body is stopped, and the turning stop region and the turning deceleration region are changed according to the turning speed of the turning body calculated from the turning angle detected by the turning angle sensor. Update boundaries.

ADVANTAGE OF THE INVENTION According to this invention, a collision with a bucket and the loading platform of a transportation vehicle can be avoided, preventing decline in working efficiency.

It is a side view showing the structure of the hydraulic excavator in the first embodiment of the present invention. 1 is a schematic diagram showing the configuration of a hydraulic drive system according to a first embodiment of the present invention; FIG. 1 is a block diagram showing the configuration of a collision avoidance device according to a first embodiment of the present invention; FIG. FIG. 2 is a perspective view and a developed view in a turning direction showing a turning restricted area in the first embodiment of the present invention; FIG. It is a figure showing the processing procedure of the controller in the 1st Embodiment of this invention. It is a block diagram showing the structure of the collision avoidance apparatus in the 2nd Embodiment of this invention. FIG. 10 is a perspective view and a developed view showing a turning restriction area in a modified example of the present invention;

A first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a side view showing the structure of the hydraulic excavator in this embodiment. Hereafter, the front side (right side in FIG. 1), rear side (left side in FIG. 1), left side (back side with respect to the paper surface of FIG. 1), right side (on the paper surface of FIG. 1) of the operator who got on the cab of the hydraulic excavator will be described. front side) are simply referred to as front side, rear side, left side, and right side.

The hydraulic excavator of this embodiment includes a travelable traveling body 1 , a revolving body 2 rotatably provided above the traveling body 1 , and a working device 3 connected to the front side of the revolving body 2 . The traveling body 1 travels by being driven by left and right travel motors 4A and 4B (see FIG. 2, which will be described later). The revolving body 2 is revolved by being driven by a revolving motor 5 (see FIG. 2 which will be described later).

The work device 3 includes a boom 6 connected to the front portion of the revolving body 2 so as to be vertically rotatable, an arm 7 connected to the tip portion of the boom 6 so as to be vertically rotatable, and A bucket 8 is connected to the portion so as to be rotatable in the vertical direction. The boom 6, the arm 7, and the bucket 8 are rotated by driving the boom cylinder 9, the arm cylinder 10, and the bucket cylinder 11, respectively.

A cab 12 on which an operator rides is provided on the front left side of the revolving body 2 . Inside the cab 12, there are provided a plurality of operating devices (details of which will be described later) operated by an operator.

A hydraulic excavator includes a hydraulic drive device that drives a hydraulic actuator according to the operation of the operating device described above. The configuration of this hydraulic drive system will be described with reference to FIG. FIG. 2 is a schematic diagram showing the configuration of the hydraulic drive system in this embodiment.

The hydraulic drive system of this embodiment includes an engine 13, variable displacement hydraulic pumps 14A and 14B driven by the engine 13, and a plurality of hydraulic actuators (more specifically, is a control valve for controlling the flow of pressure oil from the above-described travel motors 4A, 4B, swing motor 5, boom cylinder 9, arm cylinder 10, and bucket cylinder 11) and hydraulic pumps 14A, 14B to a plurality of hydraulic actuators. A device 15 and a plurality of operation devices (more specifically, traveling operation devices 16A and 16B and work operation devices 17A and 17B) for operating the control valve device 15 are provided.

Although not shown, the travel operation device 16A includes an operation lever that can be operated in the front-rear direction, a left travel pilot valve that generates and outputs a forward travel pilot pressure (hydraulic pressure) according to the amount of operation on the front side of the operation lever, and an operation lever. and a left travel pilot valve that generates and outputs a rear travel pilot pressure (hydraulic pressure) according to the operation amount of the rear side of the lever.

Similarly, although not shown, the travel operation device 16B includes an operation lever that can be operated in the front-rear direction, and a right travel pilot valve that generates and outputs a forward travel pilot pressure (hydraulic pressure) according to the amount of operation on the front side of the operation lever. and a right travel pilot valve that generates and outputs a rear travel pilot pressure (hydraulic pressure) according to the amount of operation on the rear side of the operation lever.

Although not shown, the work operation device 17A includes an operation lever that can be operated in the left-right direction and the front-rear direction, and an arm pilot valve that generates and outputs an arm dump pilot pressure (hydraulic pressure) according to the amount of operation on the left side of the operation lever. , arm pilot valve that generates and outputs arm cloud pilot pressure (hydraulic pressure) according to the amount of operation on the right side of the control lever, and generates right turn pilot pressure (hydraulic pressure) according to the amount of operation on the front side of the control lever. and a swing pilot valve that generates and outputs a left swing pilot pressure (hydraulic pressure) according to the amount of operation on the rear side of the operation lever.

Although not shown, the work operation device 17B includes an operation lever that can be operated in the left-right direction and the front-rear direction, and a bucket pilot valve that generates and outputs bucket cloud pilot pressure (hydraulic pressure) according to the amount of operation on the left side of the operation lever. , a bucket pilot valve that generates and outputs bucket dump pilot pressure (hydraulic pressure) according to the amount of operation on the right side of the operation lever, and a boom lowering pilot pressure (hydraulic pressure) according to the amount of operation on the front side of the operation lever. It has a boom pilot valve that outputs and a boom pilot valve that generates and outputs boom raising pilot pressure (hydraulic pressure) according to the operation amount on the rear side of the operation lever.

Although not shown, the control valve device 15 includes a hydraulic pilot type left travel control valve, right travel control valve, arm control valve, swing control valve, bucket control valve, and boom control valve.

The left travel control valve is switched by the front travel pilot pressure or the rear travel pilot pressure from the travel operation device 16A, and controls the flow (direction and flow rate) of pressure oil from the hydraulic pump to the left travel motor 4A. As a result, the left travel motor 4A rotates forward or backward.

Similarly, the right travel control valve is switched by the front travel pilot pressure or the rear travel pilot pressure from the travel operation device 16B, and controls the flow (direction and flow rate) of pressure oil from the hydraulic pump to the right travel motor 4B. . As a result, the right travel motor 4B rotates forward or backward.

The arm control valve is switched by the arm cloud pilot pressure or the arm dump pilot pressure from the work operation device 17A, and controls the flow (direction and flow rate) of pressure oil from the hydraulic pump to the arm cylinder 10 . Thereby, the arm cylinder 10 is extended or contracted.

The swing control valve is switched by left swing pilot pressure or right swing pilot pressure from the work operation device 17A, and controls the flow (direction and flow rate) of pressure oil from the hydraulic pump to the swing motor 5 . As a result, the turning motor 5 rotates in one direction or in the opposite direction.

The bucket control valve is switched by the bucket cloud pilot pressure or the bucket dump pilot pressure from the work operation device 17B, and controls the flow (direction and flow rate) of pressure oil from the hydraulic pump to the bucket cylinder 11 . Thereby, the bucket cylinder 11 is extended or contracted.

The boom control valve is switched by the boom raising pilot pressure or the boom lowering pilot pressure from the work operation device 17B, and controls the flow (direction and flow rate) of pressure oil from the hydraulic pump to the boom cylinder 9. As a result, the boom cylinder 9 is extended or shortened.

The above-described hydraulic excavator excavates earth and sand with the bucket 8 and loads the excavated material in the bucket 8. Thereafter, the bucket 8 ascends and the revolving body 2 revolves to transport the bucket 8 to the transport vehicle 100. The excavated material is loaded from the bucket 8 onto the loading platform 101 of the transport vehicle 100 by moving the excavated material above the loading platform 101 (see FIG. 4A, which will be described later). In this loading operation, there is a possibility that the bucket 8 and the loading platform 101 of the transport vehicle 100 collide when the revolving body 2 revolves. Therefore, the hydraulic excavator of this embodiment includes a device for avoiding collision between the bucket 8 and the loading platform 101 of the transport vehicle 100 . The configuration of this collision avoidance device will be described with reference to FIG. FIG. 3 is a block diagram showing the configuration of the collision avoidance device according to this embodiment.

The collision avoidance device of this embodiment includes a boom angle sensor 20, an arm angle sensor 21, a bucket angle sensor 22, cylinder pressure sensors 23A and 23B, pilot pressure sensors 24A and 24B, a turning speed sensor 25, a setting switch 26, a controller 27, and electromagnetic pressure reducing valves 28A and 28B.

The boom angle sensor 20 is an angle sensor attached to the base end of the boom 6 , detects the rotation angle of the boom 6 with respect to the revolving structure 2 , and outputs it to the controller 27 . The arm angle sensor 21 is an angle sensor attached to the base end of the arm 7 , detects the rotation angle of the arm 7 with respect to the boom 6 , and outputs it to the controller 27 . The bucket angle sensor 22 is an angle sensor attached to the base end of the bucket 8 , detects the rotation angle of the bucket 8 with respect to the arm 7 and outputs it to the controller 27 .

The cylinder pressure sensor 23</b>A is a pressure sensor provided in the bottom side oil chamber of the boom cylinder 9 , detects the bottom side pressure of the boom cylinder 9 and outputs it to the controller 27 . The cylinder pressure sensor 23</b>B is a pressure sensor provided in the rod-side oil chamber of the boom cylinder 9 , detects the rod-side pressure of the boom cylinder 9 and outputs it to the controller 27 .

The pilot pressure sensor 24A or 24B is a pressure sensor provided between the swing pilot valve of the work operating device 17A and the swing control valve of the control valve device 15, as shown in FIG. Pilot pressure sensor 24A or 24B detects the swing pilot pressure and outputs it to controller 27 . The turning speed sensor 25 detects the turning speed of the turning body 2 and outputs it to the controller 27 .

The setting switch 26 is provided in the cab 12, and is operated by the operator to set the excavated object loading position P1 (more specifically, as shown in FIG. and the position of the portion closest to the bucket 8) is output to the controller 27.

The pressure reducing valve 28A or 28B is provided between the swing pilot valve of the work operating device 17A and the swing control valve of the control valve device 15, as shown in FIG.

Although not shown, the controller 27 has a control unit (for example, CPU) that executes arithmetic processing and control processing based on a program, and a storage unit (for example, ROM and RAM) that stores programs and processing results. The controller 27 has a bucket position calculation section 30, a moment calculation section 31, a bucket load calculation section 32, a turning restriction area setting section 33, and a turning restriction control section 34 as functional configurations.

The bucket position calculator 30 of the controller 27 calculates the turning angle of the turning body 2 with respect to the traveling body 1 by integrating the turning speed of the turning body 2 detected by the turning speed sensor 25 . Then, based on the calculated turning angle of the turning body 2 and the turning angles of the boom 6, the arm 7, and the bucket 8 detected by the boom angle sensor 20, the arm angle sensor 21, and the bucket angle sensor 22, the A position (more specifically, the position of the lower end of the bucket 8) is calculated.

A moment calculator 31 of the controller 27 calculates a moment of the work device 3 based on the bottom side pressure and the rod side pressure of the boom cylinder 9 detected by the cylinder pressure sensors 23A and 23B. The bucket loading amount calculation unit 32 of the controller 27 calculates the moment of the working device 3 calculated by the moment calculation unit 31 and the boom angle sensor 20, the arm angle sensor 21, and the boom 6, arm 7, and arm detected by the bucket angle sensor 22. And based on the rotation angle of the bucket 8, the weight (loading amount) of the excavated material in the bucket 8 is calculated.

A rotation restriction area setting unit 33 of the controller 27 sets and stores the position of the bucket 8 calculated by the bucket position calculation unit 30 as the loading position P1 when the instruction signal from the setting switch 26 is input. .

A turning restriction area setting unit 33 of the controller 27 determines whether or not the weight of the excavated material in the bucket 8 calculated by the bucket load calculation unit 32 is equal to or greater than a preset threshold value. Further, from a state in which both of the swing pilot pressures detected by the pilot pressure sensors 24A and 24B are less than a preset threshold value, it is determined whether one of the swing pilot pressures is equal to or higher than the threshold value. to detect the start of turning. Then, when the start of rotation of the rotating body 2 is detected in a state where the weight of the excavated material in the bucket 8 is equal to or greater than the threshold value, the position of the bucket 8 calculated by the bucket position calculator 30 is set to the excavation position P2 of the bucket 8. (In other words, the end position of the excavation work or the start position of the loading work) is set and stored.

Immediately after setting the excavation position P2, the rotation restriction area setting unit 33 of the controller 27 determines the rotation stop area based on the loading position P1, the excavation position P2, and the rotation speed of the rotating body 2 detected by the rotation speed sensor 25. A turning restriction area consisting of A1 and turning deceleration area A2 is set and stored. In addition, the boundary between the turning stop area A1 and the turning deceleration area A2 is updated according to the turning speed of the turning body 2 detected by the turning speed sensor 25 at every predetermined cycle (details will be described later).

The swing restriction control section 34 of the controller 27 controls the pressure reducing valves 28A and 28B to the fully open state when the position of the bucket 8 calculated by the bucket position calculation section 30 is not in the swing deceleration region A2 and the swing stop region A1.

When the position of the bucket 8 calculated by the bucket position calculator 30 is in the swing deceleration region A2, the swing restriction control unit 34 of the controller 27 controls one of the pressure reducing valves 28A and 28B to be throttled. The rotation of the rotating body 2 in the direction approaching the loading position P1 is decelerated. The opening ratio of the pressure reducing valve in the throttled state may be a constant value regardless of the position of the bucket 8 in the revolving direction of the revolving body 2, or it may decrease as the position of the bucket 8 approaches the revolving stop area A1. may

When the position of the bucket 8 calculated by the bucket position calculation unit 30 is in the swing stop area A1, the swing restriction control unit 34 of the controller 27 controls one of the pressure reducing valves 28A and 28B to the fully closed state. The turning of the turning body 2 in the direction approaching the retracted position P1 is stopped.

Next, a specific example of a method for setting the turning stop area A1 and the turning deceleration area A2 will be described with reference to FIGS. 4(a) and 4(b). 4(a) and 4(b) are a perspective view and a developed view in the turning direction showing the turning restricted area in this embodiment.

The rotation restriction area setting unit 33 of the controller 27 horizontally moves the excavation position P2 to the position P2' in the same turning radial direction of the revolving superstructure 2, and horizontally moves the revolving superstructure 2 from the revolving central axis to the loading position P1. The distance is set to be the same as the horizontal distance from the turning center axis of the turning body 2 to the position P2'.

The turning restriction area setting unit 33 sets a turning stop angle corresponding to the turning speed of the turning body 2 (more specifically, a turning angle required from the start of control to stop the turning of the turning body 2 to the actual stop). is stored in advance, and using this, the turning stop angle is calculated from the turning speed of the turning body 2 detected by the turning speed sensor 25 . Then, on the horizontal circumference passing through the loading position P1 around the turning center axis of the revolving structure 2, a position P3 is set, which is advanced by the turning stop angle toward the position P2' with respect to the loading position P1.

The restricted turning area setting unit 33 sets a position P4 where the turning radial direction of the revolving superstructure 2 is the same for the loading position P1 and the height is the same for the positions P2 and P2'. Also, a position P5 is set where the turning radius direction of the revolving structure 2 is the same as the position P3 and the height is the same as the positions P2, P2', and P4.

The restricted turning area setting unit 33 connects the loading position P1 and the position P3 with a curved line in the turning direction of the revolving superstructure 2, connects the position P4 and the position P5 with a curved line in the revolving direction of the revolving superstructure 2, and connects the loading position P1 and the position P3. P4 is connected by a straight line in the height direction, and positions P3 and P5 are connected by a straight line in the height direction. , P4, and P5, respectively, a turning stop area A1 is set. Thereby, regardless of the position of the revolving structure 2 in the revolving direction, the height range of the revolving stop area A1 is set to be constant.

The turning restriction area setting unit 33 connects the position P3 and the position P2' with a curve in the turning direction of the revolving superstructure 2, connects the position P5 and the position P2' with a curve in the revolving direction of the revolving superstructure 2, and determines the turning center point and the position P2. ', P3, and P5 are connected with straight lines to set the turning deceleration area A2. As a result, the height range of the turning deceleration area A2 is set to gradually increase from the excavation position P2 toward the loading position P1.

Note that if the turning speed of the turning structure 2 detected by the turning speed sensor 25 increases at each predetermined cycle, the turning stop angle also increases. P3, P5) move to the excavation position P2 side. Further, if the turning speed of the turning body 2 detected by the turning speed sensor 25 decreases at each predetermined cycle, the turning stop angle also decreases. P3, P5) moves toward the loading position P1.

Next, the processing contents of the controller in this embodiment will be described with reference to FIG. FIG. 5 is a flow chart showing the processing procedure of the controller in this embodiment. It is assumed that the restricted turning area setting unit 33 of the controller 27 sets and stores the loading position P1 before step S1 in FIG.

At step S1, the restricted turning area setting unit 33 of the controller 27 determines whether or not the weight of the excavated object in the bucket 8 calculated by the bucket load calculating unit 32 is equal to or greater than a threshold value, and at step S2, The turning restriction area setting unit 33 determines whether or not the turning start of the turning body 2 has been detected. If the weight of the excavated material in the bucket 8 calculated by the bucket loading amount calculator 32 is less than the threshold value, the determination in step S1 becomes NO, and the determination is repeated. Further, if the start of turning of the turning body 2 is not detected, the determination in step S2 becomes NO, and the process returns to step S1.

If the start of rotation of the rotating body 2 is detected while the weight of the excavated material in the bucket 8 is equal to or greater than the threshold value, the determinations in steps S1 and S2 become YES, and the process proceeds to step S3. In step S3, the swing restriction region setting unit 33 detects the start of swing of the swing body 2 in a state where the weight of the excavated material in the bucket 8 is equal to or greater than the threshold value, 8 is set and stored as an excavation position P2. Then, in step S4, the restricted turning area setting unit 33 sets the turning speed turning stop area A1 and the turning deceleration area of the turning body 2 based on the loading position P1, the excavating position P2, and the preset predetermined turning speed. A turning restriction area consisting of A2 is provisionally set. Then, according to the turning speed of the turning body 2 detected by the turning speed sensor 25, the boundary between the turning stop area A1 and the turning deceleration area A2 is updated.

After that, the process proceeds to step S5, and the turning restriction control section 34 of the controller 27 determines whether or not the position of the bucket 8 calculated by the bucket position calculating section 30 is in the turning deceleration area A2. If the position of the bucket 8 is not in the turning deceleration area A2, the determination in step S5 becomes NO, and the process proceeds to step S6. In step S6, the turning restriction control section 34 determines whether or not the position of the bucket 8 calculated by the bucket position calculating section 30 is in the turning stop area A1. If the position of the bucket 8 is not in the swing stop area A1, the determination in step S6 becomes NO, and the process proceeds to step S7. In step S7, the turning restriction control unit 34 controls the pressure reducing valves 28A and 28B to be fully opened.

If the position of the bucket 8 is in the turning deceleration area A2 in step S5, the determination in step S5 becomes YES, and the process proceeds to step S8. In step S8, the turning restriction control unit 34 controls one of the pressure reducing valves 28A and 28B to be throttled to decelerate the turning of the turning body 2 in the direction of approaching the loading position P1. When the position of the bucket 8 is in the turning stop area A1 in step S6, the determination in step S6 becomes YES, and the process proceeds to step S9. In step S9, the turning restriction control unit 34 controls one of the pressure reducing valves 28A and 28B to the fully closed state to stop the turning of the turning body 2 in the direction approaching the loading position P1. Therefore, collision between the bucket 8 and the loading platform 101 of the transport vehicle 100 can be avoided.

After step S7, S8 or S9, go to step S10. In step S10, the restricted turning area setting unit 33 of the controller 27 determines whether the weight of the excavated material in the bucket 8 calculated by the bucket load calculating unit 32 is less than a threshold value. That is, it is determined whether or not the loading work has been completed.

If the weight of the excavated material in the bucket 8 calculated by the bucket loading amount calculator 32 in step S10 is equal to or greater than the threshold value (that is, if the loading operation is not completed), the determination in step S10 becomes NO. Then, the process returns to step S4. In step S<b>4 , the restricted turning area setting unit 33 updates the boundary between the turning stop area A<b>1 and the turning deceleration area A<b>2 according to the turning speed of the turning body 2 detected by the turning speed sensor 25 .

When the weight of the excavated material in the bucket 8 calculated by the bucket load calculation unit 32 in step S10 is less than the threshold value (that is, when the loading operation is completed), the determination in step S10 becomes NO, Return to step S1.

As described above, in the present embodiment, collision between the bucket 8 and the loading platform 101 of the transport vehicle 100 can be avoided. Further, since the boundary between the turning stop area A1 and the turning deceleration area A2 is updated according to the turning speed of the turning body 2, unlike the case where the boundary is fixed, the turning of the turning body 2 can be stopped excessively. do not have. Therefore, it is possible to prevent a decrease in work efficiency.

Further, in this embodiment, the height range of the turning deceleration area A2 is set to gradually increase from the excavation position P2 toward the loading position P1. As a result, unlike the case where the height range of the turning deceleration region is set to be constant, even if a combined operation of lifting the bucket 8 and turning the turning body 2 is performed at the same time, the turning of the turning body 2 is prevented. Do not slow down excessively. Therefore, it is possible to prevent a decrease in work efficiency.

In the above description, the boom angle sensor 20, the arm angle sensor 21, and the bucket angle sensor 22 constitute a posture detector for detecting the posture of the working device described in the claims. The cylinder pressure sensors 23A and 23B constitute pressure sensors that detect the pressure of the hydraulic cylinders that support the working device .

Also, the setting switch 26 constitutes a setting indicator for instructing the setting of the loading position. One function of the restricted turning area setting unit 33 of the controller 27 constitutes a loading position setting device for setting the loading position of the excavated material, and when instructed by the setting indicator, the controller calculates A loading position setting device is configured to set the position of the bucket as the loading position.

Also, the pilot pressure sensors 24A and 24B constitute a turning instruction detector that detects an instruction to turn the turning body by the operating device. One function of the restricted swing area setting unit 33 of the controller 27 constitutes an excavation position setting device that sets the excavation position of the bucket, and calculates the moment of the working device from the pressure of the hydraulic cylinder detected by the pressure sensor. Then, the weight of the excavated material in the bucket is calculated from the attitude of the work equipment detected by the attitude detector and the moment of the work equipment. The excavation position setting device is configured to set the position of the bucket calculated by the controller as the excavation position when the start of turning of the revolving body is detected based on the detection result of the turning instruction detector.

In the first embodiment, the hydraulic excavator includes cylinder pressure sensors 23A and 23B, and the controller 27 includes a moment calculator 31 that calculates the moment of the working device 3 based on the detection results of the cylinder pressure sensors 23A and 23B. and the bucket loading amount calculation unit 32 for calculating the weight of the excavated material in the bucket 8 based on the moment of the work device 3, etc., but the present invention is not limited to this and departs from the scope of the present invention. Deformation is possible within a range that does not. Instead of the cylinder pressure sensors 23A, 23B and the moment calculator 31 and bucket load calculator 32 of the controller 27, the hydraulic excavator may include, for example, a weight sensor that detects the weight of the excavated material in the bucket 8. In this case, the restricted turning area setting unit 33 of the controller 27 determines the detection results of the pilot pressure sensors 24A and 24B in a state where the weight of the excavated material in the bucket 8 detected by the weight sensor is equal to or greater than a preset threshold value. The position of the bucket 8 calculated by the bucket position calculator 30 of the controller 27 may be set as the excavation position P2 when the start of the swing of the swing body 2 is detected.

Further, in the first embodiment, the turning restriction area setting unit 33 of the controller 27 determines the detection results of the pilot pressure sensors 24A and 24B in a state where the weight of the excavated material in the bucket 8 is equal to or greater than a preset threshold value. The case where the position of the bucket 8 calculated by the bucket position calculator 30 of the controller 27 is set as the excavation position P2 when the start of the swing of the swing body 2 is detected has been described as an example, but the present invention is not limited to this. Modifications are possible without departing from the gist of the present invention. The restricted swing area setting unit 33 of the controller 27 may set the position of the bucket 8 calculated by the bucket position calculation unit 30 of the controller 27 as the excavation position P2 when the setting switch instructs to set the excavation position. good.

A second embodiment of the present invention will be described with reference to FIG. In addition, in this embodiment, the same code|symbol is attached|subjected to the part equivalent to 1st Embodiment, and description is abbreviate|omitted suitably.

FIG. 6 is a block diagram showing the configuration of the collision avoidance device in this embodiment.

The turning restriction area setting unit 33A of the controller 27 of the present embodiment adjusts the turning speed of the turning body 2 detected by the turning speed sensor 25 and the moment of the working device 3 calculated by the moment calculating unit 31 at each predetermined cycle. Accordingly, the boundary between the turning stop area A1 and the turning deceleration area A2 is updated.

More specifically, the turning limit area setting unit 33A stores in advance a turning stop angle corresponding to the turning speed of the turning body 2 and the moment of the work device 3. Using this, the turning detected by the turning speed sensor 25 is A turning stop angle is calculated from the turning speed of the body 2 and the moment of the working device 3 calculated by the moment calculating section 31 . Then, as in the first embodiment, the boundary between the turning stop area A1 and the turning deceleration area A2 (that is, the position P3 shown in FIGS. 4A and 4B) is determined based on the turning stop angle. , P5).

Also in this embodiment, collision between the bucket 8 and the loading platform 101 of the transport vehicle 100 can be avoided as in the first embodiment. Further, in the present embodiment, the boundary between the turning stop area A1 and the turning deceleration area A2 is updated in accordance with not only the turning speed of the turning body 2 but also the moment of the work device 3, thereby further preventing a decrease in work efficiency. be able to.

In the second embodiment, the hydraulic excavator includes cylinder pressure sensors 23A and 23B, and the controller 27 includes a moment calculator 31 that calculates the moment of the working device 3 based on the detection results of the cylinder pressure sensors 23A and 23B. and the bucket loading amount calculation unit 32 for calculating the weight of the excavated material in the bucket 8 based on the moment of the work device 3, etc., but the present invention is not limited to this and departs from the scope of the present invention. Deformation is possible within a range that does not. Instead of the cylinder pressure sensors 23A, 23B and the bucket loading amount calculator 32 of the controller 27, the hydraulic excavator may include, for example, a weight sensor that detects the weight of the excavated material in the bucket 8. In this case, the moment calculation section of the controller 27 may calculate the moment of the working device 3 based on the detection results of the boom angle sensor 20, the arm angle sensor 21, the bucket angle sensor 22, and the weight sensor.

Further, in the first and second embodiments, the case where the restricted turning area setting unit 33 of the controller 27 sets the turning deceleration area A2 so as to include the excavation position P2 has been described as an example. Modifications are possible without departing from the gist of the present invention. For example, as in the modification shown in FIG. 7, with the excavation position P as a reference, it does not include a preset predetermined turning angle, and turns from positions P6 and P7 advanced toward the loading position P1 by a predetermined turning angle. A deceleration area A2 may be set.

In addition, in the first and second embodiments, the hydraulic excavator has been described as having the boom angle sensor 20, the arm angle sensor 21, and the bucket angle sensor 22. However, the present invention is not limited to this. Modifications are possible without departing from the spirit. For example, instead of the boom angle sensor 20, the hydraulic excavator may include a displacement sensor that detects the stroke of the boom cylinder 9. Also, the hydraulic excavator may include a displacement sensor that detects the stroke of the arm cylinder 10 instead of the arm angle sensor 21, for example. Also, the hydraulic excavator may include a displacement sensor that detects the stroke of the bucket cylinder 11 instead of the bucket angle sensor 22, for example.

In addition, in the first and second embodiments, the hydraulic excavator includes the swing speed sensor 25 that detects the swing speed of the swing structure 2 , and the controller 27 detects the swing speed of the swing structure 2 detected by the swing speed sensor 25 . Although the case where the turning angle of the turning body 2 with respect to the traveling body 1 is calculated by integrating is described as an example, it is not limited to this, and modifications are possible within the scope of the present invention. The hydraulic excavator includes, for example, a swing angle sensor for detecting the swing angle of the swing structure 2 with respect to the traveling structure 1 instead of the swing speed sensor 25, and the controller 27 detects the swing angle of the swing structure 2 detected by the swing angle sensor. The revolving speed of the revolving body 2 may be calculated by differentiating .

Further, in the first and second embodiments, the hydraulic excavator has been described as an example in which the mechanical swing pilot valve is operated by operating the control lever, but the present invention is not limited to this. Modifications are possible within a range that does not deviate. A hydraulic excavator has, for example, a potentiometer that detects the amount of operation of an operating lever and outputs it to a controller, and an electromagnetic swing pilot valve that operates with a command current generated by the controller according to the amount of operation of the operating lever. You may prepare. In this case, since there is a potentiometer, the pilot pressure sensors 24A and 24B are unnecessary. In addition, the pressure reducing valves 28A and 28B are not required, and the controller only needs to limit the aforementioned command current in order to decelerate or stop the swing of the swing structure 2. FIG.

1 Traveling body 2 Revolving body 3 Work device 8 Bucket 17A, 17B Work operation device 20 Boom angle sensor 21 Arm angle sensor 22 Bucket angle sensor 23A, 23B Cylinder pressure sensor 24A, 24B Pilot pressure sensor 25 Turning speed sensor 26 Setting switch 27 Controller 28A, 28B pressure reducing valve 30 bucket position calculator 31 moment calculator 32 bucket loading amount calculator 33, 33A swing restriction region setting unit 34 swing limit controller

Claims (10)

a running body that can run;
a revolving body rotatably provided above the running body;
a work device connected to the revolving body and having a bucket;
a turning angle sensor that detects a turning angle of the turning body with respect to the traveling body;
A hydraulic excavator comprising an attitude detector for detecting the attitude of the working device,
a loading position setting device for setting the loading position of the excavated material;
an excavation position setting device for setting an excavation position of the bucket;
The position of the bucket is calculated from the turning angle of the revolving body detected by the revolving angle sensor and the attitude of the working device detected by the attitude detector, and the position of the revolving body is calculated according to the position of the bucket. and a controller that controls the speed of turning,
The controller sets a rotation restriction area including a rotation stop area and a rotation deceleration area based on the loading position and the excavation position. When the position of the bucket is in the swing stop area, the swing of the swing body is stopped, and the swing calculated from the swing angle detected by the swing angle sensor is decelerated. A hydraulic excavator, wherein a boundary between the swing stop region and the swing deceleration region is updated according to the swing speed of the body. a movable body;
a revolving body rotatably provided above the running body;
a work device connected to the revolving body and having a bucket;
a turning speed sensor that detects a turning speed of the turning body with respect to the traveling body;
A hydraulic excavator comprising an attitude detector for detecting the attitude of the working device,
a loading position setting device for setting the loading position of the excavated material;
an excavation position setting device for setting an excavation position of the bucket;
The position of the bucket is calculated from the swing angle of the swing body calculated from the swing speed detected by the swing speed sensor and the posture of the working device detected by the posture detector, and the position of the bucket is calculated. a controller for controlling the speed of the revolving body,
The controller sets a rotation restricted area including a rotation stop area and a rotation deceleration area based on the loading position and the excavation position. When the swing of the swing body is decelerated and the position of the bucket is in the swing stop region, the swing of the swing body is stopped, and according to the swing speed of the swing body detected by the swing speed sensor. , a hydraulic excavator characterized by updating a boundary between the swing stop area and the swing deceleration area. In the hydraulic excavator according to claim 1 or 2 ,
further comprising a pressure sensor that detects the pressure of the hydraulic cylinder that supports the working device;
The controller calculates a moment of the work device from the pressure of the hydraulic cylinder detected by the pressure sensor, and determines the swing stop region and the swing deceleration according to the swing speed of the swing body and the moment of the work device. A hydraulic excavator characterized by updating a boundary with an area. In the hydraulic excavator according to claim 1 or 2 ,
further comprising a weight sensor for detecting the weight of the excavated material in the bucket;
The controller calculates the moment of the work device from the weight of the excavated material in the bucket detected by the weight sensor and the attitude of the work device detected by the attitude detector, and the revolving speed of the revolving body. and a moment of the work device, a boundary between the rotation stop area and the rotation deceleration area is updated. In the hydraulic excavator according to claim 1 or 2 ,
The hydraulic excavator, wherein the controller sets the swing deceleration area such that the height range of the swing deceleration area gradually increases from the excavation position toward the loading position. In the hydraulic excavator according to claim 5 ,
The hydraulic excavator, wherein the controller sets the swing deceleration region from a position advanced by a preset swing angle toward the loading position with respect to the excavation position. In the hydraulic excavator according to claim 5 ,
The hydraulic excavator, wherein the controller sets the swing stop area so that the height range of the swing stop area is constant. In the hydraulic excavator according to claim 1 or 2 ,
a pressure sensor that detects the pressure of a hydraulic cylinder that supports the working device;
a turning instruction detector that detects an instruction to turn the turning body by an operating device;
The excavation position setting device calculates a moment of the work device from the pressure of the hydraulic cylinder detected by the pressure sensor, and calculates the moment of the work device from the posture of the work device detected by the posture detector and the moment of the work device. The weight of the excavated material in the bucket is calculated, and in a state where the weight of the excavated material in the bucket is equal to or greater than a preset threshold value, the turning of the revolving body is started based on the detection result of the turning instruction detector. A hydraulic excavator characterized in that, when detected, the position of the bucket calculated by the controller is set as the excavation position. In the hydraulic excavator according to claim 1 or 2 ,
a weight sensor for detecting the weight of excavated material in the bucket;
a turning instruction detector that detects an instruction to turn the turning body by an operating device;
The excavation position setting device causes the revolving body to revolve based on the detection result of the revolving instruction detector in a state where the weight of the excavated material in the bucket detected by the weight sensor is equal to or greater than a preset threshold value. A hydraulic excavator, wherein the position of the bucket calculated by the controller is set as the excavation position when the start is detected. In the hydraulic excavator according to claim 1 or 2 ,
further comprising a setting indicator for instructing setting of the loading position;
The hydraulic excavator, wherein the loading position setting device sets the position of the bucket calculated by the controller as the loading position when instructed by the setting indicator.

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