JP7420619B2 - excavator - Google Patents

Description

The present disclosure relates to excavators.

2. Description of the Related Art Excavators are known that have an attachment that has a hook for lifting a suspended load.

In Patent Document 1, a hook is attached to an attachment, a boom angle and arm angle detector is provided, and a boom cylinder bottom pressure and rod pressure detector is provided, and the detected values of the boom angle and arm angle as well as the boom In a crane-spec hydraulic excavator equipped with a controller that calculates the hanging load of the hook from the detected values of cylinder bottom pressure and rod pressure, an electromagnetic proportional valve is installed in parallel with the remote control valve for arm operation, boom operation, or both. and input signals from the crane specification switch and automatic command switch to the controller, and when both switch signals are on, calculate the hook position based on the detected values of the boom angle and arm angle, Disclosed is an automatic vertical lifting device for a hydraulic excavator with crane specifications, characterized in that the controller is configured to output a drive signal to the electromagnetic proportional valve so that the hook always moves up and down on the same vertical line. has been done.

Japanese Patent Application Publication No. 2000-226862

By the way, in the work of hoisting a suspended load with a hook, there is a possibility that the suspended load may shake when the suspended load breaks off the ground.

Therefore, in view of the above problems, it is an object of the present invention to provide a shovel that can suitably lift a suspended load.

In order to achieve the above object, an embodiment of the present invention includes an attachment having a hook for suspending a suspended load, a suspended load vibration detection unit that detects a change in the center of gravity position of the suspended load due to vibration, and a suspended load vibration detection unit that controls the attachment. the suspended load vibration detection unit detects the amplitude of the center of gravity position of the suspended load, the period of vibration of the suspended load, and the angle of vibration of the suspended load; , controlling the attachment to determine the amplitude of the center of gravity position of the suspended load detected by the suspended load vibration detection unit and the period of vibration of the suspended load with respect to the shaking of the suspended load when the suspended load cuts off the ground; , and controlling the attachment to control vibration of the suspended load based on the angle of vibration of the suspended load.

According to the above-described embodiment, it is possible to provide a shovel that can suitably lift a suspended load.

FIG. 1 is a side view of a shovel as an excavator according to the present embodiment. FIG. 1 is a diagram schematically showing an example of the configuration of a shovel according to the present embodiment. FIG. 1 is a diagram schematically showing an example of the configuration of a hydraulic system of an excavator according to the present embodiment. 1 is a diagram schematically showing an example of a component related to an operation system of the excavator hydraulic system according to the present embodiment. FIG. 2 is a diagram schematically showing an example of a component related to an earth and sand load detection function of the excavator according to the present embodiment. FIG. 3 is a schematic diagram illustrating parameters related to calculation of soil weight in an excavator attachment. FIG. 3 is a partially enlarged view illustrating the relationship of forces acting on the bucket. It is a block diagram explaining the processing of the 1st weight calculation part. FIG. 3 is a conceptual diagram illustrating vibration damping control according to the present embodiment. It is a graph showing the relationship between the position of the hook and the center of gravity position of the suspended load.

Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings.

[Excavator overview]
First, an overview of the shovel 100 according to the present embodiment will be described with reference to FIG. 1.

FIG. 1 is a side view of a shovel 100 as an excavator according to the present embodiment.

The excavator 100 according to the present embodiment includes a lower traveling body 1, an upper rotating body 3 that is rotatably mounted on the lower traveling body 1 via a rotating mechanism 2, a boom 4, and an arm that constitute an attachment (work machine). 5, a bucket 6, and a cabin 10.

The lower traveling body 1 causes the excavator 100 to travel by hydraulically driving a pair of right and left crawlers by travel hydraulic motors 1L and 1R (see FIG. 2, which will be described later). That is, the pair of traveling hydraulic motors 1L and 1R (an example of traveling motors) drive the lower traveling body 1 (crawler) as a driven part.

The upper rotating body 3 rotates relative to the lower traveling body 1 by being driven by a swing hydraulic motor 2A (see FIG. 2, which will be described later). That is, the swing hydraulic motor 2A is a swing drive unit that drives the rotating upper structure 3 as a driven part, and can change the direction of the rotating upper structure 3.

Note that the upper revolving body 3 may be electrically driven by an electric motor (hereinafter referred to as a "swing motor") instead of the swing hydraulic motor 2A. That is, like the swing hydraulic motor 2A, the swing electric motor is a swing drive unit that drives the upper revolving structure 3 as a driven part, and can change the direction of the upper revolving structure 3.

The boom 4 is pivotally attached to the front center of the upper revolving structure 3 so that it can be lifted up and down, and an arm 5 is pivotally attached to the tip of the boom 4 so that it can be moved up and down. A bucket 6 is pivotally mounted so as to be movable up and down. The boom 4, the arm 5, and the bucket 6 are each hydraulically driven by a boom cylinder 7, an arm cylinder 8, and a bucket cylinder 9 as hydraulic actuators.

Note that the bucket 6 is an example of an end attachment, and depending on the work content, other end attachments may be attached to the tip of the arm 5, such as a bucket for slopes, a bucket for dredging, or a breaker, instead of the bucket 6. etc. may be attached.

The rod side end of the bucket cylinder 9 and the bucket 6 are connected by a bucket link 6a. Specifically, the upper end of the bucket link 6a is rotatably connected to the rod side end of the bucket cylinder 9 and the arm link 6c via a bucket cylinder top pin 6b. The lower end side of the bucket link 6a is rotatably connected to a bracket on the rear surface of the bucket 6 via a bucket pin 6d. Further, a hook 6e for crane work is attached to the bucket link 6a so that it can be stored and rotated.

During excavation work, the hook 6e is stored in a hook storage section 6f mainly composed of a bucket link 6a. This is to prevent the operation of the bucket 6 from being hindered. On the other hand, during crane work, the tip thereof is configured to protrude from the hook storage portion 6f.

Further, the hook storage section 6f may be provided with a detection device (not shown) that detects the storage state of the hook 6e. For example, the detection device is a switch that is in a conductive state when the hook 6e is present in the hook storage portion 6f, and is in a disconnected state when the hook 6e is not present in the hook storage portion 6f, and is in a disconnected state when the hook 6e is stored in the hook storage portion 6f. It is provided in the hook storage section 6f. Note that the detection signal of the detection device is taken into a controller 30, which will be described later.

The cabin 10 is a driver's room in which an operator rides, and is mounted on the front left side of the upper revolving structure 3.

[Shovel configuration]
Next, with reference to FIG. 2 in addition to FIG. 1, a specific configuration of the shovel 100 according to the present embodiment will be described.

FIG. 2 is a diagram schematically showing an example of the configuration of the shovel 100 according to the present embodiment.

In FIG. 2, the mechanical power system, hydraulic oil line, pilot line, and electric control system are shown by double lines, solid lines, broken lines, and dotted lines, respectively.

The drive system of the excavator 100 according to the present embodiment includes an engine 11, a regulator 13, a main pump 14, and a control valve 17. Further, as described above, the hydraulic drive system of the excavator 100 according to the present embodiment includes traveling hydraulic motors 1L and 1R that hydraulically drive the lower traveling body 1, the upper rotating body 3, the boom 4, the arm 5, and the bucket 6, respectively. , a swing hydraulic motor 2A, a boom cylinder 7, an arm cylinder 8, a bucket cylinder 9, and other hydraulic actuators.

The engine 11 is a main power source in the hydraulic drive system, and is mounted, for example, at the rear of the revolving upper structure 3. Specifically, the engine 11 rotates at a constant speed at a preset target rotation speed under direct or indirect control by a controller 30, which will be described later, and drives the main pump 14 and the pilot pump 15. The engine 11 is, for example, a diesel engine that uses light oil as fuel.

The regulator 13 controls the discharge amount of the main pump 14. For example, the regulator 13 adjusts the angle (tilting angle) of the swash plate of the main pump 14 in response to a control command from the controller 30. The regulator 13 includes, for example, regulators 13L and 13R, as described later.

The main pump 14 is, for example, mounted at the rear of the upper revolving structure 3 like the engine 11, and supplies hydraulic oil to the control valve 17 through a high-pressure hydraulic line. The main pump 14 is driven by the engine 11 as described above. The main pump 14 is, for example, a variable displacement hydraulic pump, and as described above, under the control of the controller 30, the stroke length of the piston is adjusted by adjusting the tilt angle of the swash plate by the regulator 13, and the stroke length of the piston is adjusted. The flow rate (discharge pressure) is controlled. The main pump 14 includes, for example, main pumps 14L and 14R, as described below.

The control valve 17 is, for example, a hydraulic control device that is mounted in the center of the revolving upper structure 3 and controls the hydraulic drive system in accordance with the operation of the operating device 26 by an operator. As described above, the control valve 17 is connected to the main pump 14 via a high-pressure hydraulic line, and controls the hydraulic oil supplied from the main pump 14 to the hydraulic actuator (travel hydraulic motor 1L) according to the operating state of the operating device 26. , 1R, swing hydraulic motor 2A, boom cylinder 7, arm cylinder 8, and bucket cylinder 9). Specifically, the control valve 17 includes control valves 171 to 176 that control the flow rate and flow direction of the hydraulic oil supplied from the main pump 14 to each of the hydraulic actuators. More specifically, the control valve 171 corresponds to the travel hydraulic motor 1L, the control valve 172 corresponds to the travel hydraulic motor 1R, and the control valve 173 corresponds to the swing hydraulic motor 2A. Further, the control valve 174 corresponds to the bucket cylinder 9, the control valve 175 corresponds to the boom cylinder 7, and the control valve 176 corresponds to the arm cylinder 8. Further, the control valve 175 includes, for example, control valves 175L and 175R as described later, and the control valve 176 includes, for example, control valves 176L and 176R as described later. Details of the control valves 171 to 176 will be described later.

The operating system of the excavator 100 according to this embodiment includes a pilot pump 15 and an operating device 26. Further, the operation system of the excavator 100 includes a shuttle valve 32 as a configuration related to a machine control function by a controller 30, which will be described later.

The pilot pump 15 is mounted, for example, on the rear part of the revolving upper structure 3, and supplies pilot pressure to the operating device 26 via a pilot line. The pilot pump 15 is, for example, a fixed capacity hydraulic pump, and is driven by the engine 11 as described above.

The operating device 26 is provided near the cockpit of the cabin 10, and is an operation input means for the operator to operate various operating elements (lower traveling structure 1, upper rotating structure 3, boom 4, arm 5, bucket 6, etc.). It is. In other words, the operating device 26 allows the operator to operate the hydraulic actuators (i.e., travel hydraulic motors 1L, 1R, swing hydraulic motor 2A, boom cylinder 7, arm cylinder 8, bucket cylinder 9, etc.) that drive the respective operating elements. This is an operation input means for performing. The operating device 26 is connected to the control valve 17 directly through a pilot line on the secondary side thereof, or indirectly through a shuttle valve 32, which will be described later, provided in the pilot line on the secondary side. As a result, pilot pressure can be input to the control valve 17 according to the operating states of the lower traveling body 1, the upper rotating body 3, the boom 4, the arm 5, the bucket 6, etc. in the operating device 26. Therefore, the control valve 17 can drive each hydraulic actuator according to the operating state of the operating device 26. The operating device 26 includes, for example, a lever device that operates the arm 5 (arm cylinder 8). Further, the operating device 26 includes, for example, lever devices 26A to 26C that operate each of the boom 4 (boom cylinder 7), bucket 6 (bucket cylinder 9), and upper swing structure 3 (swing hydraulic motor 2A) (FIG. 4). reference). Further, the operating device 26 includes, for example, a lever device and a pedal device that operate each of the left and right pair of crawlers (traveling hydraulic motors 1L, 1R) of the lower traveling body 1.

The shuttle valve 32 has two inlet ports and one outlet port, and outputs hydraulic fluid having a higher pilot pressure of the pilot pressures input to the two inlet ports to the outlet port. The shuttle valve 32 has two inlet ports, one of which is connected to the operating device 26 and the other of which is connected to the proportional valve 31 . The outlet port of shuttle valve 32 is connected through a pilot line to the pilot port of a corresponding control valve in control valve 17 (see FIG. 4 for details). Therefore, the shuttle valve 32 can cause the higher of the pilot pressure generated by the operating device 26 and the pilot pressure generated by the proportional valve 31 to act on the pilot port of the corresponding control valve. In other words, the controller 30, which will be described later, outputs a pilot pressure higher than the secondary side pilot pressure output from the operating device 26 from the proportional valve 31, so that the controller 30 can perform corresponding control regardless of the operation of the operating device 26 by the operator. The valves can be controlled and the operation of various operating elements can be controlled. The shuttle valve 32 includes, for example, shuttle valves 32AL, 32AR, 32BL, 32BR, 32CL, and 32CR, as described below.

Note that the operating devices 26 (left operating lever, right operating lever, left running lever, and right running lever) may be of an electric type that outputs an electric signal instead of a hydraulic pilot type that outputs a pilot pressure. In this case, the electrical signal from the operating device 26 is input to the controller 30, and the controller 30 controls each of the control valves 171 to 176 in the control valve 17 according to the input electrical signal. The operation of various hydraulic actuators is realized according to the operation contents for 26. For example, the control valves 171 to 176 in the control valve 17 may be electromagnetic solenoid spool valves driven by commands from the controller 30. Furthermore, for example, a solenoid valve that operates in response to an electrical signal from the controller 30 may be arranged between the pilot pump 15 and the pilot port of each of the control valves 171 to 176. In this case, when a manual operation is performed using the electric operating device 26, the controller 30 controls the solenoid valve to increase or decrease the pilot pressure using an electric signal corresponding to the amount of operation (for example, the amount of lever operation). By doing so, each of the control valves 171 to 176 can be operated in accordance with the operation content of the operating device 26.

The control system of the excavator 100 according to the present embodiment includes a controller 30, a discharge pressure sensor 28, an operation pressure sensor 29, a proportional valve 31, a display device 40, an input device 42, an audio output device 43, and a memory. It includes a device 47, a boom angle sensor S1, an arm angle sensor S2, a bucket angle sensor S3, a body tilt sensor S4, a turning state sensor S5, an imaging device S6, a positioning device P1, and a communication device T1.

The controller 30 (an example of a control device) is provided in the cabin 10, for example, and controls the drive of the excavator 100. The functions of the controller 30 may be realized by arbitrary hardware, software, or a combination thereof. For example, the controller 30 is mainly a microcomputer that includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a non-volatile auxiliary storage device, various input/output interfaces, etc. configured. The controller 30 realizes various functions by, for example, executing various programs stored in a ROM or a nonvolatile auxiliary storage device on the CPU.

For example, the controller 30 sets a target rotation speed based on a work mode or the like that is preset by a predetermined operation by an operator or the like, and performs drive control to rotate the engine 11 at a constant rate.

Further, for example, the controller 30 outputs a control command to the regulator 13 as necessary to change the discharge amount of the main pump 14.

Further, for example, the controller 30 performs control related to a machine guidance function that guides manual operation of the shovel 100 by an operator using the operating device 26, for example. Further, the controller 30 controls, for example, a machine control function that automatically supports manual operation of the shovel 100 by an operator through the operating device 26. That is, the controller 30 includes the machine guidance section 50 as a functional section related to the machine guidance function and the machine control function. Further, the controller 30 includes an earth and sand load processing section 60, which will be described later.

Note that some of the functions of the controller 30 may be realized by another controller (control device). That is, the functions of the controller 30 may be realized in a distributed manner by a plurality of controllers. For example, the machine guidance function and the machine control function may be realized by a dedicated controller (control device).

The discharge pressure sensor 28 detects the discharge pressure of the main pump 14. A detection signal corresponding to the discharge pressure detected by the discharge pressure sensor 28 is taken into the controller 30. The discharge pressure sensor 28 includes, for example, discharge pressure sensors 28L and 28R, as described later.

As described above, the operating pressure sensor 29 measures the pilot pressure on the secondary side of the operating device 26, that is, the operating state (for example, operating direction, operating amount, etc.) regarding each operating element (i.e., hydraulic actuator) in the operating device 26. Detects the pilot pressure corresponding to the operation content). Detection signals of pilot pressures corresponding to operating states of the lower traveling body 1 , the upper rotating body 3 , the boom 4 , the arm 5 , the bucket 6 , etc. in the operating device 26 by the operating pressure sensor 29 are taken into the controller 30 . The operating pressure sensor 29 includes, for example, operating pressure sensors 29A to 29C, as described later.

Note that instead of the operating pressure sensor 29, other sensors capable of detecting the operating state of each operating element in the operating device 26, such as the operating amount (tilting amount) and tilting direction of the lever devices 26A to 26C, etc., may be used. An encoder, potentiometer, etc. may be provided.

The proportional valve 31 is provided in a pilot line connecting the pilot pump 15 and the shuttle valve 32, and is configured to be able to change its flow path area (cross-sectional area through which hydraulic oil can flow). The proportional valve 31 operates according to a control command input from the controller 30. Thereby, the controller 30 controls the hydraulic fluid discharged from the pilot pump 15 to the proportional valve 31 and Via the shuttle valve 32, the pilot port of the corresponding control valve in the control valve 17 can be supplied. The proportional valve 31 includes, for example, proportional valves 31AL, 31AR, 31BL, 31BR, 31CL, and 31CR, as described later.

The display device 40 is provided in a location within the cabin 10 that is easily visible to a seated operator, and displays various information images under the control of the controller 30. The display device 40 may be connected to the controller 30 via an in-vehicle communication network such as a CAN (Controller Area Network), or may be connected to the controller 30 via a one-to-one dedicated line.

The input device 42 is provided within the reach of an operator seated in the cabin 10, receives various operational inputs from the operator, and outputs signals corresponding to the operational inputs to the controller 30. The input device 42 includes a touch panel mounted on the display of a display device that displays various information images, a knob switch provided at the tip of the lever part of the lever devices 26A to 26C, a button switch installed around the display device 40, and a lever. , toggles, rotary dials, etc. A signal corresponding to the operation content on the input device 42 is taken into the controller 30.

The input device 42 also includes a mode changeover switch 42a. The mode changeover switch 42a is a switch for changing over the working mode of the excavator 100. The work mode means the type of work performed by the excavator 100, and includes, for example, a crane mode, a normal mode, and the like. Note that the mode changeover switch 42a may be a software switch on a touch panel arranged on the screen of the display device 40, a hardware switch installed around the display device 40, or a switch inside the cabin 10. It may also be a switch installed in another position.

The audio output device 43 is provided in the cabin 10, for example, is connected to the controller 30, and outputs audio under the control of the controller 30. The audio output device 43 is, for example, a speaker, a buzzer, or the like. The audio output device 43 outputs various information as audio in response to an audio output command from the controller 30.

The storage device 47 is provided within the cabin 10, for example, and stores various information under the control of the controller 30. The storage device 47 is, for example, a nonvolatile storage medium such as a semiconductor memory. The storage device 47 may store information output by various devices while the shovel 100 is in operation, or may store information acquired via the various devices before the shovel 100 starts operating. The storage device 47 may store, for example, data regarding the target construction surface acquired via the communication device T1 or the like or set via the input device 42 or the like. The target construction surface may be set (saved) by the operator of the excavator 100, or may be set by a construction manager or the like.

The boom angle sensor S1 is attached to the boom 4, and measures the elevation angle (hereinafter referred to as "boom angle") of the boom 4 with respect to the revolving upper structure 3, for example, the angle of elevation of the boom 4 with respect to the rotation plane of the revolving upper structure 3 in a side view. Detect the angle formed by the straight line connecting the supporting points at both ends. The boom angle sensor S1 may include, for example, a rotary encoder, an acceleration sensor, a 6-axis sensor, an IMU (Inertial Measurement Unit), and the like. The boom angle sensor S1 may also include a potentiometer using a variable resistor, a cylinder sensor that detects the stroke amount of the hydraulic cylinder (boom cylinder 7) corresponding to the boom angle, and the like. The same applies to the arm angle sensor S2 and the bucket angle sensor S3 below. A detection signal corresponding to the boom angle by the boom angle sensor S1 is taken into the controller 30.

The arm angle sensor S2 is attached to the arm 5, and measures the rotation angle of the arm 5 with respect to the boom 4 (hereinafter referred to as "arm angle"), for example, when viewed from the side, the arm angle sensor S2 Detect the angle formed by the straight line connecting the supporting points at both ends. A detection signal corresponding to the arm angle by the arm angle sensor S2 is taken into the controller 30.

The bucket angle sensor S3 is attached to the bucket 6, and measures the rotation angle of the bucket 6 with respect to the arm 5 (hereinafter referred to as "bucket angle"), for example, when viewed from the side, the bucket angle sensor S3 measures the rotation angle of the bucket 6 with respect to the arm 5. Detects the angle formed by the straight line connecting the fulcrum and the tip (cutting edge). A detection signal corresponding to the bucket angle by the bucket angle sensor S3 is taken into the controller 30.

The body inclination sensor S4 detects the inclination state of the body (upper rotating body 3 or lower traveling body 1) with respect to a horizontal plane. The body inclination sensor S4 is, for example, attached to the revolving upper structure 3, and is configured to measure the inclination angle (hereinafter referred to as "front-rear inclination angle" and "left-right Detect the angle of inclination). The body tilt sensor S4 may include, for example, a rotary encoder, an acceleration sensor, a 6-axis sensor, an IMU, etc. A detection signal corresponding to the inclination angle (the longitudinal inclination angle and the left-right inclination angle) by the aircraft inclination sensor S4 is taken into the controller 30.

The turning state sensor S5 outputs detection information regarding the turning state of the upper revolving structure 3. The turning state sensor S5 detects, for example, the turning angular velocity and turning angle of the upper rotating body 3. The turning state sensor S5 may include, for example, a gyro sensor, a resolver, a rotary encoder, and the like. Detection signals corresponding to the turning angle and turning angular velocity of the upper rotating structure 3 by the turning state sensor S5 are taken into the controller 30.

An imaging device S6 serving as a space recognition device images the surroundings of the excavator 100. The imaging device S6 includes a camera S6F that images the front of the shovel 100, a camera S6L that images the left side of the shovel 100, a camera S6R that images the right side of the shovel 100, and a camera S6B that images the rear side of the shovel 100. .

The camera S6F is attached to the ceiling of the cabin 10, that is, inside the cabin 10, for example. Moreover, the camera S6F may be attached to the outside of the cabin 10, such as the roof of the cabin 10 or the side of the boom 4. The camera S6L is attached to the left end of the upper surface of the revolving upper structure 3, the camera S6R is attached to the right end of the upper surface of the revolving upper structure 3, and the camera S6B is attached to the rear end of the upper surface of the revolving upper structure 3.

The imaging devices S6 (cameras S6F, S6B, S6L, and S6R) are each, for example, a monocular wide-angle camera having a very wide angle of view. Further, the imaging device S6 may be a stereo camera, a distance image camera, or the like. An image captured by the imaging device S6 is taken into the controller 30 via the display device 40.

The imaging device S6 as a space recognition device may function as an object detection device. In this case, the imaging device S6 may detect objects existing around the excavator 100. Objects to be detected may include, for example, people, animals, vehicles, construction machines, buildings, holes, and the like. Further, the imaging device S6 may calculate the distance from the imaging device S6 or the shovel 100 to the recognized object. The imaging device S6 as an object detection device may include, for example, a stereo camera, a distance image sensor, and the like. The space recognition device is, for example, a monocular camera having an image sensor such as a CCD or CMOS, and outputs the captured image to the display device 40. Further, the space recognition device may be configured to calculate the distance from the space recognition device or shovel 100 to the recognized object. Further, in addition to the imaging device S6, other object detection devices such as an ultrasonic sensor, a millimeter wave radar, a LIDAR, an infrared sensor, etc. may be provided as a space recognition device. When using a millimeter wave radar, ultrasonic sensor, laser radar, etc. as the space recognition device 80, by transmitting a large number of signals (laser light, etc.) to an object and receiving the reflected signals, The distance and direction of objects may also be detected.

Note that the imaging device S6 may be directly communicably connected to the controller 30.

A boom rod pressure sensor S7R and a boom bottom pressure sensor S7B are attached to the boom cylinder 7. An arm rod pressure sensor S8R and an arm bottom pressure sensor S8B are attached to the arm cylinder 8. A bucket rod pressure sensor S9R and a bucket bottom pressure sensor S9B are attached to the bucket cylinder 9. Boom rod pressure sensor S7R, boom bottom pressure sensor S7B, arm rod pressure sensor S8R, arm bottom pressure sensor S8B, bucket rod pressure sensor S9R, and bucket bottom pressure sensor S9B are also collectively referred to as "cylinder pressure sensors."

The boom rod pressure sensor S7R detects the pressure in the rod side oil chamber of the boom cylinder 7 (hereinafter referred to as "boom rod pressure"), and the boom bottom pressure sensor S7B detects the pressure in the bottom side oil chamber of the boom cylinder 7 (hereinafter referred to as "boom rod pressure"). , "boom bottom pressure"). The arm rod pressure sensor S8R detects the pressure in the rod side oil chamber of the arm cylinder 8 (hereinafter referred to as "arm rod pressure"), and the arm bottom pressure sensor S8B detects the pressure in the bottom side oil chamber of the arm cylinder 8 (hereinafter referred to as "arm rod pressure"). , "arm bottom pressure") is detected. The bucket rod pressure sensor S9R detects the pressure in the rod side oil chamber of the bucket cylinder 9 (hereinafter referred to as "bucket rod pressure"), and the bucket bottom pressure sensor S9B detects the pressure in the bottom side oil chamber of the bucket cylinder 9 (hereinafter referred to as "bucket rod pressure"). , "bucket bottom pressure").

The positioning device P1 measures the position and orientation of the upper revolving body 3. The positioning device P1 is, for example, a GNSS (Global Navigation Satellite System) compass, detects the position and orientation of the upper revolving body 3, and a detection signal corresponding to the position and orientation of the upper revolving body 3 is taken into the controller 30. . Further, among the functions of the positioning device P1, the function of detecting the orientation of the upper revolving structure 3 may be replaced by an orientation sensor attached to the upper revolving structure 3.

The communication device T1 communicates with an external device through a predetermined network including a mobile communication network, a satellite communication network, an Internet network, etc., which terminate at a base station. The communication device T1 is, for example, a mobile communication module compatible with mobile communication standards such as LTE (Long Term Evolution), 4G (4th Generation), and 5G (5th Generation), or a satellite communication module for connecting to a satellite communication network. modules, etc.

The machine guidance unit 50 controls the excavator 100 regarding, for example, a machine guidance function. The machine guidance unit 50 conveys work information such as the distance between the target construction surface and the tip of the attachment, specifically, the work area of the end attachment, to the operator through the display device 40, the audio output device 43, etc. . Data regarding the target construction surface is stored in advance in the storage device 47, for example, as described above. Data regarding the target construction surface is expressed, for example, in a reference coordinate system. The reference coordinate system is, for example, the world geodetic system. The world geodetic system is a three-dimensional orthogonal system with its origin at the center of gravity of the Earth, the X-axis pointing toward the intersection of the Greenwich meridian and the equator, the Y-axis pointing toward 90 degrees East longitude, and the Z-axis pointing toward the North Pole. It is an XYZ coordinate system. The operator may set an arbitrary point on the construction site as a reference point, and use the input device 42 to set the target construction surface based on the relative positional relationship with the reference point. The working parts of the bucket 6 are, for example, the toe of the bucket 6, the back surface of the bucket 6, and the like. Further, when a breaker is employed as the end attachment instead of the bucket 6, for example, the tip of the breaker corresponds to the work part. The machine guidance unit 50 notifies the operator of work information through the display device 40, the audio output device 43, etc., and guides the operator in operating the shovel 100 through the operating device 26.

Further, the machine guidance unit 50 executes control of the excavator 100 regarding, for example, a machine control function. For example, the machine guidance unit 50 controls at least one of the boom 4, the arm 5, and the bucket 6 so that the target construction surface and the tip position of the bucket 6 match when an operator manually performs an excavation operation. One may be operated automatically.

The machine guidance unit 50 receives information from the boom angle sensor S1, arm angle sensor S2, bucket angle sensor S3, body tilt sensor S4, turning state sensor S5, imaging device S6, positioning device P1, communication device T1, input device 42, etc. get. Then, the machine guidance unit 50 calculates the distance between the bucket 6 and the target construction surface based on the acquired information, and calculates the distance between the bucket 6 and the target construction surface using the audio from the audio output device 43 and the image displayed on the display device 40. 6 and the target construction surface, and so that the tip of the attachment (specifically, the work area such as the toe or back of the bucket 6) matches the target construction surface. Automatically control the movement of attachments. The machine guidance section 50 includes a position calculation section 51, a distance calculation section 52, an information transmission section 53, an automatic control section 54, and a turning angle calculation section 55 as detailed functional configurations regarding the machine guidance function and machine control function. and a relative angle calculation unit 56.

The position calculation unit 51 calculates the position of a predetermined positioning target. For example, the position calculation unit 51 calculates a coordinate point in the reference coordinate system of the tip of the attachment, specifically, a working part such as the toe or back of the bucket 6. Specifically, the position calculation unit 51 calculates the coordinate point of the work area of the bucket 6 from the elevation angles (boom angle, arm angle, and bucket angle) of each of the boom 4, arm 5, and bucket 6.

The distance calculation unit 52 calculates the distance between two positioning targets. For example, the distance calculation unit 52 calculates the distance between the tip of the attachment, specifically, the work site such as the toe or back of the bucket 6 and the target construction surface. Further, the distance calculation unit 52 may calculate the angle (relative angle) between the back surface of the bucket 6 as a work site and the target construction surface.

The information transmission unit 53 transmits (notifies) various information to the operator of the excavator 100 through predetermined notification means such as the display device 40 and the audio output device 43. The information transmission unit 53 notifies the operator of the excavator 100 of the magnitudes (degrees) of various distances etc. calculated by the distance calculation unit 52. For example, the distance (size) between the tip of the bucket 6 and the target construction surface is communicated to the operator using at least one of visual information from the display device 40 and auditory information from the audio output device 43. The information transmitting unit 53 also uses at least one of the visual information from the display device 40 and the auditory information from the audio output device 43 to determine the relative angle between the back surface of the bucket 6 as a work area and the target construction surface. ) may be communicated to the operator.

Specifically, the information transmission unit 53 uses intermittent sounds from the audio output device 43 to inform the operator of the distance (for example, vertical distance) between the work area of the bucket 6 and the target construction surface. In this case, the information transmission unit 53 may shorten the interval between the intermittent sounds as the vertical distance becomes smaller, and lengthen the sensation of the intermittent sound as the vertical distance becomes larger. Further, the information transmission section 53 may use continuous sound, or may change the pitch, strength, etc. of the sound to represent the difference in the vertical distance. Further, the information transmission unit 53 may issue an alarm through the audio output device 43 when the tip of the bucket 6 is lower than the target construction surface, that is, exceeds the target construction surface. The alarm is, for example, a continuous sound that is significantly louder than an intermittent sound.

The information transmission unit 53 also transmits information about the tip of the attachment, specifically, the distance between the working part of the bucket 6 and the target construction surface, and the relative angle between the back surface of the bucket 6 and the target construction surface. The size and the like may be displayed on the display device 40 as work information. Under the control of the controller 30, the display device 40 displays, for example, the image data received from the imaging device S6 as well as the work information received from the information transmission unit 53. The information transmitting unit 53 may transmit the magnitude of the vertical distance to the operator using, for example, an image of an analog meter, an image of a bar graph indicator, or the like.

The automatic control unit 54 automatically supports manual operation of the shovel 100 by the operator through the operating device 26 by automatically operating the actuator. Specifically, as will be described later, the automatic control unit 54 controls control valves (specifically, The pilot pressure acting on control valve 173, control valves 175L, 175R, and control valve 174) can be adjusted individually and automatically. Thereby, the automatic control unit 54 can automatically operate each hydraulic actuator. Control regarding the machine control function by the automatic control unit 54 may be executed, for example, when a predetermined switch included in the input device 42 is pressed. The predetermined switch is, for example, a machine control switch (hereinafter referred to as "MC (Machine Control) switch"), and is a knob switch that is gripped by the operator of the operating device 26 (for example, a lever device corresponding to the operation of the arm 5). may be placed at the tip of the The following description will proceed on the assumption that the machine control function is enabled when the MC switch is pressed.

For example, when the MC switch or the like is pressed down, the automatic control unit 54 automatically controls at least one of the boom cylinder 7 and the bucket cylinder 9 in accordance with the operation of the arm cylinder 8 in order to support excavation work or shaping work. to expand and contract. Specifically, when the operator manually closes the arm 5 (hereinafter referred to as "arm closing operation"), the automatic control unit 54 controls the target construction surface and the work area such as the toe or back of the bucket 6. At least one of the boom cylinder 7 and the bucket cylinder 9 is automatically expanded and contracted so that the positions of the boom cylinder 7 and the bucket cylinder 9 coincide with each other. In this case, the operator can close the arm 5 while aligning the toe of the bucket 6 with the target construction surface, for example, by simply operating a lever device corresponding to the operation of the arm 5 to close the arm.

Furthermore, when the MC switch or the like is pressed, the automatic control unit 54 may automatically rotate the swing hydraulic motor 2A (an example of an actuator) in order to bring the upper swing structure 3 directly toward the target construction surface. . Hereinafter, the control performed by the controller 30 (automatic control unit 54) to cause the upper revolving structure 3 to face the target construction surface will be referred to as "face-to-face control." As a result, the operator or the like can perform the target construction on the upper rotating structure 3 by simply pressing a predetermined switch, or by simply operating a lever device 26C, which will be described later, that corresponds to a swing operation while the switch is pressed. It can be placed directly against the surface. Furthermore, by simply pressing the MC switch, the operator can cause the upper revolving body 3 to directly face the target construction surface and start the machine control function related to the above-mentioned excavation work on the target construction surface.

For example, when the upper revolving body 3 of the excavator 100 is directly facing the target construction surface, the tip of the attachment (for example, the toe or back surface of the bucket 6 as a working part) is moved toward the target construction surface ( It is in a state where it can be moved along the inclination direction of the uphill slope. Specifically, when the upper rotating body 3 of the excavator 100 is directly facing the target construction surface, the operating surface of the attachment (attachment operating surface) perpendicular to the rotation plane of the shovel 100 is in the target construction corresponding to the cylindrical body. This is a state including the normal line of the surface (in other words, a state along the normal line).

If the attachment operating surface of the shovel 100 is not in a state that includes the normal to the target construction surface corresponding to the cylinder, the tip of the attachment cannot move the target construction surface in the inclined direction. Therefore, as a result, the shovel 100 cannot properly perform construction on the target construction surface. On the other hand, the automatic control unit 54 can cause the upper rotating structure 3 to face directly by automatically rotating the swing hydraulic motor 2A. Thereby, the shovel 100 can appropriately perform construction on the target construction surface.

In the direct facing control, the automatic control unit 54 calculates, for example, the left end vertical distance between the left end coordinate point of the toe of the bucket 6 and the target construction surface (hereinafter simply referred to as the "left end vertical distance"), and the left end coordinate point of the toe of the bucket 6. When the right end vertical distance between the right end coordinate point and the target construction surface (hereinafter simply referred to as "right end vertical distance") becomes equal, it is determined that the excavator is directly facing the target construction surface. In addition, the automatic control unit 54 controls the automatic control unit 54 not when the left end vertical distance and the right end vertical distance become equal (that is, when the difference between the left end vertical distance and the right end vertical distance becomes zero), but when the difference is less than a predetermined value. , it may be determined that the shovel 100 is directly facing the target construction surface.

Furthermore, in the front facing control, the automatic control unit 54 may operate the swing hydraulic motor 2A based on the difference between the left end vertical distance and the right end vertical distance, for example. Specifically, when the lever device 26C corresponding to the swing operation is operated with a predetermined switch such as the MC switch being pressed down, the lever device 26C moves in the direction of directly facing the upper rotating structure 3 to the target construction surface. Determine whether or not it has been manipulated. For example, when the lever device 26C is operated in a direction that increases the vertical distance between the toe of the bucket 6 and the target construction surface (uphill surface), the automatic control unit 54 does not perform the direct facing control. On the other hand, when the swing operation lever is operated in a direction that reduces the vertical distance between the toe of the bucket 6 and the target construction surface (uphill surface), the automatic control unit 54 executes the facing control. As a result, the automatic control unit 54 can operate the swing hydraulic motor 2A so that the difference between the left end vertical distance and the right end vertical distance becomes smaller. Thereafter, when the difference is less than a predetermined value or becomes zero, the automatic control unit 54 stops the swing hydraulic motor 2A. The automatic control unit 54 also sets a turning angle at which the difference is less than a predetermined value or zero as a target angle, and sets the target angle and the current turning angle (specifically, based on the detection signal of the turning state sensor S5). The operation of the swing hydraulic motor 2A may be controlled so that the angular difference from the detected value becomes zero. In this case, the turning angle is, for example, the angle of the longitudinal axis of the upper revolving structure 3 with respect to the reference direction.

Note that, as described above, when a swing electric motor is mounted on the excavator 100 instead of the swing hydraulic motor 2A, the automatic control unit 54 performs direct control with the swing electric motor (an example of an actuator) as a control target. .

The turning angle calculation unit 55 calculates the turning angle of the upper rotating body 3. Thereby, the controller 30 can specify the current orientation of the revolving upper structure 3. The turning angle calculation unit 55 calculates the angle of the longitudinal axis of the upper rotating body 3 with respect to the reference direction as the turning angle, for example, based on the output signal of the GNSS compass included in the positioning device P1. Further, the turning angle calculating section 55 may calculate the turning angle based on the detection signal of the turning state sensor S5. Further, if a reference point is set at the construction site, the turning angle calculation unit 55 may set the direction in which the reference point is viewed from the turning axis as the reference direction.

The rotation angle indicates the direction in which the attachment operating surface extends with respect to the reference direction. The attachment operating plane is, for example, a virtual plane that traverses the attachment, and is arranged perpendicular to the turning plane. The rotation plane is, for example, a virtual plane that includes the bottom surface of the rotation frame perpendicular to the rotation axis. For example, when the controller 30 (machine guidance unit 50) determines that the attachment operating surface includes the normal to the target construction surface, the controller 30 (machine guidance unit 50) determines that the upper rotating structure 3 is directly facing the target construction surface.

The relative angle calculating unit 56 calculates a turning angle (relative angle) necessary for causing the upper revolving structure 3 to directly face the target construction surface. The relative angle is, for example, formed between the direction of the longitudinal axis of the upper revolving body 3 when the upper revolving body 3 is directly opposed to the target construction surface and the current direction of the longitudinal axis of the upper revolving body 3. It is a relative angle. The relative angle calculation section 56 calculates the relative angle based on, for example, the data regarding the target construction surface stored in the storage device 47 and the turning angle calculated by the turning angle calculation section 55.

When the lever device 26C corresponding to the swing operation is operated while a predetermined switch such as the MC switch is pressed, the automatic control unit 54 rotates the upper rotating structure 3 in a direction to directly face the target construction surface. Determine whether or not. When the automatic control unit 54 determines that the upper rotating body 3 has been rotated in a direction to directly face the target construction surface, the automatic control unit 54 sets the relative angle calculated by the relative angle calculation unit 56 as the target angle. Then, when the change in the swing angle after the lever device 26C is operated reaches the target angle, the automatic control unit 54 determines that the upper swing structure 3 is directly facing the target construction surface, and turns the swing hydraulic motor 2A. You can stop the movement. Thereby, the automatic control unit 54 can cause the upper revolving structure 3 to face the target construction surface based on the configuration shown in FIG. 2 . Although the above-mentioned embodiment of direct facing control shows an example of direct facing control for the target construction surface, the present invention is not limited to this. For example, in the scooping operation when loading temporarily stored earth and sand into a dump truck, a target excavation trajectory corresponding to the target volume is generated, and the turning operation is directly controlled so that the attachment faces the target excavation trajectory. You can. In this case, the target excavation trajectory is changed each time a scooping operation is performed. Therefore, after discharging the earth to the dump truck, the control is performed to directly face the newly changed target excavation trajectory.

Moreover, the swing hydraulic motor 2A has a first port 2A1 and a second port 2A2. The oil pressure sensor 21 detects the pressure of the hydraulic oil in the first port 2A1 of the swing hydraulic motor 2A. The oil pressure sensor 22 detects the pressure of the hydraulic oil at the second port 2A2 of the swing hydraulic motor 2A. Detection signals corresponding to the discharge pressures detected by the oil pressure sensors 21 and 22 are taken into the controller 30.

Further, the first port 2A1 is connected to a hydraulic oil tank via a relief valve 23. The relief valve 23 opens when the pressure on the first port 2A1 side reaches a predetermined relief pressure, and discharges the hydraulic oil on the first port 2A1 side to the hydraulic oil tank. Similarly, the second port 2A2 is connected to the hydraulic oil tank via the relief valve 24. The relief valve 24 opens when the pressure on the second port 2A2 side reaches a predetermined relief pressure, and discharges the hydraulic oil on the second port 2A2 side to the hydraulic oil tank.

[Excavator hydraulic system]
Next, with reference to FIG. 3, the hydraulic system of the excavator 100 according to the present embodiment will be described.

FIG. 3 is a diagram schematically showing an example of the configuration of the hydraulic system of the excavator 100 according to the present embodiment.

In FIG. 3, the mechanical power system, hydraulic oil line, pilot line, and electric control system are shown by double lines, solid lines, broken lines, and dotted lines, respectively, as in FIG. 2 and the like.

The hydraulic system realized by the hydraulic circuit circulates hydraulic oil from each of the main pumps 14L and 14R driven by the engine 11 to the hydraulic oil tank via the center bypass oil passages C1L and C1R and the parallel oil passages C2L and C2R. let

The center bypass oil passage C1L starts from the main pump 14L, passes through control valves 171, 173, 175L, and 176L arranged in the control valve 17 in order, and reaches the hydraulic oil tank.

The center bypass oil passage C1R starts from the main pump 14R, passes through control valves 172, 174, 175R, and 176R arranged in the control valve 17 in order, and reaches the hydraulic oil tank.

The control valve 171 is a spool valve that supplies the hydraulic oil discharged from the main pump 14L to the travel hydraulic motor 1L, and discharges the hydraulic oil discharged by the travel hydraulic motor 1L to a hydraulic oil tank.

The control valve 172 is a spool valve that supplies the hydraulic oil discharged from the main pump 14R to the travel hydraulic motor 1R, and discharges the hydraulic oil discharged by the travel hydraulic motor 1R to the hydraulic oil tank.

The control valve 173 is a spool valve that supplies the hydraulic oil discharged from the main pump 14L to the hydraulic swing motor 2A and discharges the hydraulic oil discharged by the hydraulic swing motor 2A to the hydraulic oil tank.

The control valve 174 is a spool valve that supplies the hydraulic oil discharged from the main pump 14R to the bucket cylinder 9 and discharges the hydraulic oil in the bucket cylinder 9 to the hydraulic oil tank.

The control valves 175L and 175R are spool valves that respectively supply the hydraulic oil discharged by the main pumps 14L and 14R to the boom cylinder 7 and discharge the hydraulic oil in the boom cylinder 7 to the hydraulic oil tank.

The control valves 176L, 176R supply the hydraulic oil discharged by the main pumps 14L, 14R to the arm cylinder 8, and discharge the hydraulic oil in the arm cylinder 8 to the hydraulic oil tank.

The control valves 171, 172, 173, 174, 175L, 175R, 176L, and 176R respectively adjust the flow rate of hydraulic oil supplied to and discharged from the hydraulic actuator, and control the flow direction according to the pilot pressure acting on the pilot port. or switch between them.

The parallel oil passage C2L supplies hydraulic oil of the main pump 14L to the control valves 171, 173, 175L, and 176L in parallel with the center bypass oil passage C1L. Specifically, the parallel oil passage C2L branches from the center bypass oil passage C1L on the upstream side of the control valve 171, and supplies hydraulic oil for the main pump 14L in parallel to each of the control valves 171, 173, 175L, and 176R. configured as possible. As a result, when the flow of hydraulic oil through the center bypass oil passage C1L is restricted or blocked by any of the control valves 171, 173, and 175L, the parallel oil passage C2L supplies hydraulic oil to the downstream control valve. can.

The parallel oil passage C2R supplies hydraulic oil of the main pump 14R to the control valves 172, 174, 175R, and 176R in parallel with the center bypass oil passage C1R. Specifically, the parallel oil passage C2R branches from the center bypass oil passage C1R on the upstream side of the control valve 172, and supplies hydraulic oil for the main pump 14R in parallel to each of the control valves 172, 174, 175R, and 176R. configured as possible. The parallel oil passage C2R can supply hydraulic oil to a downstream control valve when the flow of hydraulic oil passing through the center bypass oil passage C1R is restricted or blocked by any one of the control valves 172, 174, and 175R.

The regulators 13L and 13R adjust the discharge amounts of the main pumps 14L and 14R by adjusting the tilt angles of the swash plates of the main pumps 14L and 14R, respectively, under the control of the controller 30.

The discharge pressure sensor 28L detects the discharge pressure of the main pump 14L, and a detection signal corresponding to the detected discharge pressure is taken into the controller 30. The same applies to the discharge pressure sensor 28R. Thereby, the controller 30 can control the regulators 13L, 13R according to the discharge pressures of the main pumps 14L, 14R.

In the center bypass oil passages C1L and C1R, negative control throttles (hereinafter referred to as "negative control throttles") 18L and 18R are provided between the most downstream control valves 176L and 176R, respectively, and the hydraulic oil tank. As a result, the flow of hydraulic oil discharged by the main pumps 14L, 14R is restricted by the negative control throttles 18L, 18R. The negative control apertures 18L and 18R generate a control pressure (hereinafter referred to as "negative control pressure") for controlling the regulators 13L and 13R.

The negative control pressure sensors 19L and 19R detect negative control pressure, and a detection signal corresponding to the detected negative control pressure is taken into the controller 30.

The controller 30 may control the regulators 13L, 13R to adjust the discharge amount of the main pumps 14L, 14R according to the discharge pressures of the main pumps 14L, 14R detected by the discharge pressure sensors 28L, 28R. For example, the controller 30 may reduce the discharge amount by controlling the regulator 13L and adjusting the swash plate tilt angle of the main pump 14L in response to an increase in the discharge pressure of the main pump 14L. The same applies to the regulator 13R. Thereby, the controller 30 controls the total horsepower of the main pumps 14L, 14R so that the absorption horsepower of the main pumps 14L, 14R, which is expressed as the product of the discharge pressure and the discharge amount, does not exceed the output horsepower of the engine 11. be able to.

Further, the controller 30 may adjust the discharge amount of the main pumps 14L, 14R by controlling the regulators 13L, 13R according to the negative control pressure detected by the negative control pressure sensors 19L, 19R. For example, the controller 30 decreases the discharge amount of the main pumps 14L, 14R as the negative control pressure increases, and increases the discharge amount of the main pumps 14L, 14R as the negative control pressure decreases.

Specifically, when the excavator 100 is in a standby state (the state shown in FIG. 3) in which none of the hydraulic actuators are operated, the hydraulic fluid discharged from the main pumps 14L and 14R flows through the center bypass oil passages C1L and C1R. It passes through to negative control apertures 18L and 18R. The flow of hydraulic oil discharged from the main pumps 14L, 14R increases the negative control pressure generated upstream of the negative control throttles 18L, 18R. As a result, the controller 30 reduces the discharge amount of the main pumps 14L, 14R to the minimum allowable discharge amount, and suppresses pressure loss (pumping loss) when the discharged hydraulic oil passes through the center bypass oil passages C1L, C1R. .

On the other hand, when any of the hydraulic actuators is operated through the operating device 26, the hydraulic fluid discharged from the main pumps 14L, 14R is transferred to the hydraulic actuator to be operated via the control valve corresponding to the hydraulic actuator to be operated. Flow into. The flow of hydraulic oil discharged from the main pumps 14L, 14R reduces or disappears in the amount reaching the negative control throttles 18L, 18R, thereby reducing the negative control pressure generated upstream of the negative control throttles 18L, 18R. As a result, the controller 30 can increase the discharge amount of the main pumps 14L, 14R, circulate sufficient hydraulic oil to the hydraulic actuator to be operated, and reliably drive the hydraulic actuator to be operated.

[Configuration details regarding excavator machine control functions]
Next, details of the configuration regarding the machine control function of the excavator 100 will be described with reference to FIG. 4.

FIG. 4 is a diagram schematically showing an example of a component related to an operation system of the hydraulic system of the excavator 100 according to the present embodiment. Specifically, FIG. 4(A) is a diagram showing an example of a pilot circuit that applies pilot pressure to control valves 175L and 175R that hydraulically control the boom cylinder 7. Moreover, FIG. 4(B) is a diagram showing an example of a pilot circuit that applies pilot pressure to the control valve 174 that hydraulically controls the bucket cylinder 9. Moreover, FIG. 4(C) is a diagram showing an example of a pilot circuit that applies pilot pressure to the control valve 173 that hydraulically controls the swing hydraulic motor 2A.

Further, for example, as shown in FIG. 4(A), the lever device 26A is used by an operator or the like to operate the boom cylinder 7 corresponding to the boom 4. The lever device 26A uses hydraulic oil discharged from the pilot pump 15 to output pilot pressure to the secondary side according to the operation content.

The shuttle valve 32AL has two inlet ports connected to the pilot line on the secondary side of the lever device 26A, which corresponds to the operation in the raising direction of the boom 4 (hereinafter referred to as "boom raising operation"), and the secondary side of the proportional valve 31AL. The outlet port is connected to the right pilot port of control valve 175L and the left pilot port of control valve 175R.

The shuttle valve 32AR has two inlet ports connected to the pilot line on the secondary side of the lever device 26A, which corresponds to the operation in the lowering direction of the boom 4 (hereinafter referred to as "boom lowering operation"), and the secondary side of the proportional valve 31AR. The outlet port is connected to the right pilot port of the control valve 175R.

In other words, the lever device 26A applies pilot pressure depending on the operation details (eg, operation direction and operation amount) to the pilot ports of the control valves 175L and 175R via the shuttle valves 32AL and 32AR. Specifically, when the boom is operated to raise the boom, the lever device 26A outputs pilot pressure according to the operation amount to one inlet port of the shuttle valve 32AL, and the right side of the control valve 175L via the shuttle valve 32AL. and the left pilot port of the control valve 175R. In addition, when the boom is lowered, the lever device 26A outputs pilot pressure according to the amount of operation to one inlet port of the shuttle valve 32AR, and transmits the pilot pressure to the right pilot port of the control valve 175R via the shuttle valve 32AR. to act on.

The proportional valve 31AL operates according to a control current input from the controller 30. Specifically, the proportional valve 31AL uses hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other inlet port of the shuttle valve 32AL. Thereby, the proportional valve 31AL can adjust the pilot pressure acting on the right pilot port of the control valve 175L and the left pilot port of the control valve 175R via the shuttle valve 32AL.

The proportional valve 31AR operates according to a control current input from the controller 30. Specifically, proportional valve 31AR uses hydraulic oil discharged from pilot pump 15 to output pilot pressure according to the control current input from controller 30 to the other inlet port of shuttle valve 32AR. Thereby, the proportional valve 31AR can adjust the pilot pressure acting on the right pilot port of the control valve 175R via the shuttle valve 32AR.

In other words, the proportional valves 31AL and 31AR can adjust the pilot pressure output to the secondary side so that the control valves 175L and 175R can be stopped at any valve position regardless of the operating state of the lever device 26A.

The proportional valve 33AL functions as a machine control control valve similarly to the proportional valve 31AL. The proportional valve 33AL is arranged in a conduit connecting the operating device 26 and the shuttle valve 32AL, and is configured to be able to change the flow area of the conduit. In this embodiment, the proportional valve 33AL operates according to a control command output by the controller 30. Therefore, regardless of the operation of the operating device 26 by the operator, the controller 30 reduces the pressure of the hydraulic fluid discharged by the operating device 26, and then connects the corresponding control valve in the control valve 17 via the shuttle valve 32AL. can be supplied to the pilot port.

Similarly, the proportional valve 33AR functions as a control valve for machine control. The proportional valve 33AR is arranged in a conduit connecting the operating device 26 and the shuttle valve 32AR, and is configured to be able to change the flow area of the conduit. In this embodiment, the proportional valve 33AR operates according to a control command output by the controller 30. Therefore, regardless of the operation of the operating device 26 by the operator, the controller 30 reduces the pressure of the hydraulic fluid discharged by the operating device 26, and then connects the corresponding control valve in the control valve 17 via the shuttle valve 32AR. can be supplied to the pilot port.

The operating pressure sensor 29A detects the content of the operator's operation on the lever device 26A in the form of pressure (operating pressure), and a detection signal corresponding to the detected pressure is taken into the controller 30. Thereby, the controller 30 can grasp the details of the operation on the lever device 26A.

The controller 30 directs the hydraulic fluid discharged from the pilot pump 15 to the right pilot port of the control valve 175L and the control valve 175L via the proportional valve 31AL and the shuttle valve 32AL, regardless of the operator's boom raising operation on the lever device 26A. It can be fed to the left pilot port of valve 175R. The controller 30 also directs the hydraulic oil discharged from the pilot pump 15 to the right pilot port of the control valve 175R via the proportional valve 31AR and the shuttle valve 32AR, regardless of the boom lowering operation of the lever device 26A by the operator. can be supplied to That is, the controller 30 can automatically control the raising and lowering operations of the boom 4. Further, even if a specific operating device 26 is being operated, the controller 30 can forcibly stop the operation of the hydraulic actuator corresponding to that specific operating device 26.

The proportional valve 33AL operates according to a control command (current command) output by the controller 30. Then, the pilot pressure caused by the hydraulic oil introduced from the pilot pump 15 to the right pilot port of the control valve 175L and the left pilot port of the control valve 175R via the lever device 26A, the proportional valve 33AL, and the shuttle valve 32AL is reduced. The proportional valve 33AR operates according to a control command (current command) output by the controller 30. Then, the pilot pressure caused by the hydraulic oil introduced from the pilot pump 15 to the right pilot port of the control valve 175R via the lever device 26A, the proportional valve 33AR, and the shuttle valve 32AR is reduced. The pilot pressures of the proportional valves 33AL and 33AR can be adjusted so that the control valves 175L and 175R can be stopped at arbitrary valve positions.

With this configuration, even when the operator is performing a boom raising operation, the controller 30 can control the raising side pilot port of the control valve 175 (the left pilot port of the control valve 175L and the control valve The closing operation of the boom 4 can be forcibly stopped by reducing the pilot pressure acting on the right pilot port of 175R. The same applies to the case where the lowering operation of the boom 4 is forcibly stopped when the operator is performing the boom lowering operation.

Alternatively, the controller 30 controls the proportional valve 31AR as necessary even when the operator is performing a boom raising operation, and controls the proportional valve 31AR on the opposite side of the raising side pilot port of the control valve 175. By increasing the pilot pressure acting on the lowering side pilot port of the control valve 175 (the right pilot port of the control valve 175R) and forcibly returning the control valve 175 to the neutral position, the boom 4 is forced to move upward. It may be stopped. In this case, the proportional valve 33AL may be omitted. The same applies to the case where the lowering operation of the boom 4 is forcibly stopped when the operator is performing a boom lowering operation.

As shown in FIG. 4(B), the lever device 26B is used by an operator or the like to operate the bucket cylinder 9 corresponding to the bucket 6. The lever device 26B uses the hydraulic oil discharged from the pilot pump 15 to output pilot pressure to the secondary side according to the operation content.

The shuttle valve 32BL has two inlet ports connected to the pilot line on the secondary side of the lever device 26B, which corresponds to the operation in the closing direction of the bucket 6 (hereinafter referred to as "bucket closing operation"), and the secondary side of the proportional valve 31BL. The outlet port is connected to the left pilot port of the control valve 174.

The shuttle valve 32BR has two inlet ports connected to the pilot line on the secondary side of the lever device 26B, which corresponds to the operation in the opening direction of the bucket 6 (hereinafter referred to as "bucket opening operation"), and the secondary side of the proportional valve 31BR. The outlet port is connected to the right pilot port of the control valve 174.

That is, the lever device 26B applies pilot pressure depending on the operation content to the pilot port of the control valve 174 via the shuttle valves 32BL and 32BR. Specifically, when the bucket is operated to close, the lever device 26B outputs a pilot pressure corresponding to the operation amount to one inlet port of the shuttle valve 32BL, and the left side of the control valve 174 via the shuttle valve 32BL. act on the pilot port. Furthermore, when the bucket is operated to open, the lever device 26B outputs pilot pressure according to the operation amount to one inlet port of the shuttle valve 32BR, and outputs the pilot pressure to the right pilot port of the control valve 174 via the shuttle valve 32BR. to act on.

The proportional valve 31BL operates according to a control current input from the controller 30. Specifically, the proportional valve 31BL uses hydraulic oil discharged from the pilot pump 15 to output pilot pressure according to the control current input from the controller 30 to the other pilot port of the shuttle valve 32BL. Thereby, the proportional valve 31BL can adjust the pilot pressure acting on the left pilot port of the control valve 174 via the shuttle valve 32BL.

The proportional valve 31BR operates according to the control current output by the controller 30. Specifically, the proportional valve 31BR uses hydraulic oil discharged from the pilot pump 15 to output pilot pressure according to the control current input from the controller 30 to the other pilot port of the shuttle valve 32BR. Thereby, the proportional valve 31BR can adjust the pilot pressure acting on the right pilot port of the control valve 174 via the shuttle valve 32BR.

In other words, the proportional valves 31BL and 31BR can adjust the pilot pressure output to the secondary side so that the control valve 174 can be stopped at any valve position, regardless of the operating state of the lever device 26B.

The proportional valve 33BL functions as a machine control control valve similarly to the proportional valve 31BL. The proportional valve 33BL is arranged in a conduit connecting the operating device 26 and the shuttle valve 32BL, and is configured to be able to change the flow area of the conduit. In this embodiment, the proportional valve 33BL operates according to a control command output by the controller 30. Therefore, regardless of the operation of the operating device 26 by the operator, the controller 30 reduces the pressure of the hydraulic fluid discharged by the operating device 26, and then connects the corresponding control valve in the control valve 17 via the shuttle valve 32BL. can be supplied to the pilot port.

Similarly, the proportional valve 33BR functions as a control valve for machine control. The proportional valve 33BR is arranged in a conduit connecting the operating device 26 and the shuttle valve 32BR, and is configured to be able to change the flow area of the conduit. In this embodiment, the proportional valve 33BR operates according to a control command output by the controller 30. Therefore, regardless of the operation of the operating device 26 by the operator, the controller 30 reduces the pressure of the hydraulic fluid discharged by the operating device 26, and then connects the corresponding control valve in the control valve 17 via the shuttle valve 32BR. can be supplied to the pilot port.

The operating pressure sensor 29B detects the content of the operator's operation on the lever device 26B in the form of pressure (operating pressure), and a detection signal corresponding to the detected pressure is taken into the controller 30. Thereby, the controller 30 can grasp the operation details of the lever device 26B.

The controller 30 supplies the hydraulic oil discharged from the pilot pump 15 to the left pilot port of the control valve 174 via the proportional valve 31BL and the shuttle valve 32BL, regardless of the operator's bucket closing operation on the lever device 26B. can be done. Further, the controller 30 directs the hydraulic oil discharged from the pilot pump 15 to the pilot port on the right side of the control valve 174 via the proportional valve 31BR and the shuttle valve 32BR, regardless of the operator's bucket opening operation on the lever device 26B. can be supplied to That is, the controller 30 can automatically control the opening and closing operations of the bucket 6. Furthermore, even if a specific operating device 26 is being operated, the controller 30 can forcibly stop the operation of the hydraulic actuator corresponding to that specific operating device 26.

Note that the proportional valves 33BL and 33BR that forcibly stop the operation of the bucket 6 when the operator is performing a bucket closing operation or a bucket opening operation are performed when the boom raising operation or boom lowering operation is performed by the operator. This is the same as the operation of the proportional valves 33AL and 33AR, which forcibly stop the operation of the boom 4 when the boom 4 is closed, and a redundant explanation will be omitted.

Further, for example, as shown in FIG. 4(C), the lever device 26C is used by an operator or the like to operate the swing hydraulic motor 2A corresponding to the upper swing structure 3 (swing mechanism 2). The lever device 26C uses hydraulic oil discharged from the pilot pump 15 to output pilot pressure to the secondary side according to the operation content.

The shuttle valve 32CL has two inlet ports connected to a pilot line on the secondary side of a lever device 26C corresponding to a leftward turning operation (hereinafter referred to as "left turning operation") of the upper rotating body 3, and a proportional valve 31CL. The outlet port is connected to the pilot port on the left side of the control valve 173.

The shuttle valve 32CR has two inlet ports connected to a pilot line on the secondary side of a lever device 26C corresponding to a rightward rotation operation (hereinafter referred to as "right rotation operation") of the upper rotating body 3, and a proportional valve. 31CR, and its outlet port is connected to the right pilot port of the control valve 173.

That is, the lever device 26C applies pilot pressure to the pilot port of the control valve 173 via the shuttle valves 32CL and 32CR in accordance with the content of the operation in the left and right direction. Specifically, when the lever device 26C is operated to turn left, the lever device 26C outputs pilot pressure according to the operation amount to one inlet port of the shuttle valve 32CL, and the left side of the control valve 173 via the shuttle valve 32CL. act on the pilot port. Furthermore, when the lever device 26C is operated to turn to the right, the lever device 26C outputs pilot pressure according to the amount of operation to one inlet port of the shuttle valve 32CR, and the right pilot Act on the port.

The proportional valve 31CL operates according to a control current input from the controller 30. Specifically, the proportional valve 31CL uses hydraulic oil discharged from the pilot pump 15 to output pilot pressure according to the control current input from the controller 30 to the other pilot port of the shuttle valve 32CL. Thereby, the proportional valve 31CL can adjust the pilot pressure acting on the left pilot port of the control valve 173 via the shuttle valve 32CL.

The proportional valve 31CR operates according to the control current output by the controller 30. Specifically, proportional valve 31CR uses hydraulic oil discharged from pilot pump 15 to output pilot pressure according to the control current input from controller 30 to the other pilot port of shuttle valve 32CR. Thereby, the proportional valve 31CR can adjust the pilot pressure acting on the right pilot port of the control valve 173 via the shuttle valve 32CR.

In other words, the proportional valves 31CL and 31CR can adjust the pilot pressure output to the secondary side so that the control valve 173 can be stopped at any valve position regardless of the operating state of the lever device 26C.

The proportional valve 33CL functions as a control valve for machine control similarly to the proportional valve 31CL. The proportional valve 33CL is arranged in a conduit connecting the operating device 26 and the shuttle valve 32CL, and is configured to be able to change the flow area of the conduit. In this embodiment, the proportional valve 33CL operates according to a control command output by the controller 30. Therefore, regardless of the operation of the operating device 26 by the operator, the controller 30 reduces the pressure of the hydraulic fluid discharged by the operating device 26, and then connects the corresponding control valve in the control valve 17 via the shuttle valve 32CL. can be supplied to the pilot port.

Similarly, the proportional valve 33CR functions as a control valve for machine control. The proportional valve 33CR is arranged in a conduit connecting the operating device 26 and the shuttle valve 32CR, and is configured to be able to change the flow area of the conduit. In this embodiment, the proportional valve 33CR operates according to a control command output by the controller 30. Therefore, regardless of the operation of the operating device 26 by the operator, the controller 30 reduces the pressure of the hydraulic fluid discharged by the operating device 26 and then sends the pressure to the corresponding control valve in the control valve 17 via the shuttle valve 32CR. can be supplied to the pilot port.

The operating pressure sensor 29C detects the operating state of the lever device 26C by the operator as pressure, and a detection signal corresponding to the detected pressure is taken into the controller 30. Thereby, the controller 30 can grasp the operation details of the lever device 26C in the left and right directions.

The controller 30 supplies the hydraulic oil discharged from the pilot pump 15 to the left pilot port of the control valve 173 via the proportional valve 31CL and the shuttle valve 32CL, regardless of the operator's left turning operation on the lever device 26C. can be done. The controller 30 also directs the hydraulic fluid discharged from the pilot pump 15 to the right pilot of the control valve 173 through the proportional valve 31CR and the shuttle valve 32CR, regardless of the operator's right-hand rotation operation on the lever device 26C. It can be fed to a port. That is, the controller 30 can automatically control the turning operation of the upper revolving structure 3 in the left-right direction. Further, even if a specific operating device 26 is being operated, the controller 30 can forcibly stop the operation of the hydraulic actuator corresponding to that specific operating device 26.

Note that the proportional valves 33CL and 33CR, which forcefully stop the operation of the upper rotating body 3 when the operator is performing a swinging operation, are operated by the operator to raise the boom or lower the boom. This is similar to the operation of the proportional valves 33AL and 33AR, which forcibly stop the operation of the boom 4 in the event of an accident, and a duplicate explanation will be omitted.

Note that the excavator 100 may further include a configuration that automatically opens and closes the arm 5 and a configuration that automatically moves the lower traveling body 1 forward and backward. In this case, in the hydraulic system, the components related to the operation system of the arm cylinder 8, the components related to the operation system of the travel hydraulic motor 1L, and the components related to the operation of the travel hydraulic motor 1R are the components related to the operation system of the boom cylinder 7. The structure may be similar to that of the other parts (FIGS. 4(A) to 4(C)).

[Configuration details regarding the excavator's earth and sand load detection function]
Next, with reference to FIG. 5, details of the configuration of the earth and sand load detection function of the excavator 100 according to the present embodiment will be described. FIG. 5 is a diagram schematically showing an example of a component related to the earth and sand load detection function of the excavator 100 according to the present embodiment.

As described above with reference to FIG. 3, the controller 30 includes the earth and sand load processing unit 60 as a functional unit related to the function of detecting the load of earth and sand excavated by the bucket 6.

The earth and sand load processing section 60 includes a loaded object weight calculation section 61, a maximum loaded amount detection section 62, an additional loaded amount calculation section 63, a remaining loaded amount calculation section 64, and a loaded object gravity center calculation section 65.

Here, an example of the operation of loading earth and sand (loaded material) onto a dump truck by the shovel 100 according to the present embodiment will be described.

First, the shovel 100 excavates earth and sand using the bucket 6 by controlling the attachment at the excavation position (excavation operation). Next, the excavator 100 rotates the upper revolving body 3 and moves the bucket 6 from the excavation position to the earth releasing position (swinging operation). A dump truck bed is located below the soil release position. Next, at the earth dumping position, the shovel 100 controls the attachment to dump the earth and sand in the bucket 6, thereby loading the earth and sand in the bucket 6 onto the bed of the dump truck (earth dumping operation). Next, the shovel 100 rotates the upper revolving body 3 and moves the bucket 6 from the earth dumping position to the excavation position (swinging operation). By repeating these operations, the shovel 100 loads the excavated earth and sand onto the bed of the dump truck.

The loaded object weight calculation unit 61 calculates the weight of the earth and sand (loaded object) in the bucket 6. The loaded object weight calculation section 61 includes a first weight calculation section 611 , a second weight calculation section 612 , a third weight calculation section 613 , and a switching determination section 614 .

The first weight calculation unit 611 to the third weight calculation unit 613 all calculate the weight of the earth and sand (loaded object) in the bucket 6. On the other hand, the first weight calculating section 611 to the third weight calculating section 613 have different methods of detecting the weight of earth and sand. Furthermore, the first to third weight calculation units 611 to 613 have different timings of detecting the weight of earth and sand during the operation of the shovel 100. The first weight calculation unit 611 calculates the earth and sand weight based on the thrust of the boom cylinder 7. The second weight calculation unit 612 calculates the weight of earth and sand based on the thrust of the upper rotating structure 3 during turning. The third weight calculation unit 613 calculates the earth and sand weight based on the thrust of the bucket cylinder 9. Note that the method of calculating the earth and sand weight in the first to third weight calculating sections 611 to 613 will be described later.

The switching determination unit 614 switches the mode related to the timing of detecting the earth and sand weight. That is, the switching determination unit 614 determines which of the earth and sand weights calculated by the first weight calculation unit 611 to the third weight calculation unit 613 should be used as the earth and sand weight output by the loaded object weight calculation unit 61. to switch.

In addition, in the loaded object weight calculation section 61, all of the first weight calculation section 611 to the third weight calculation section 613 are constantly calculating the respective earth and sand weights, and the switching judgment section 614 switches the mode. The structure may be such that one of the earth and sand weights calculated by the weight calculation units 611 to 613 is used as the earth and sand weight output by the load weight calculation unit 61.

In addition, the load weight calculation unit 61 switches the weight calculation unit that calculates the earth and sand weight by the switching determination unit 614 switching the mode, that is, among the first weight calculation unit 611 to the third weight calculation unit 613, The configuration may be such that the processing of any one weight calculation section is made to function while the processing of the other weight calculation sections is stopped. Further, the first weight calculation unit 611 constantly calculates the weight of earth and sand without depending on the judgment of the switching judgment unit 614, and the second weight calculation unit 612 and the third weight calculation unit 613 are selected by the switching judgment unit 614. The structure may be such that the earth and sand weight is calculated only when the soil weight is calculated.

The maximum loading amount detection unit 62 detects the maximum loading amount of a dump truck to be loaded with earth and sand. For example, the maximum loading amount detection unit 62 identifies a dump truck to be loaded with earth and sand based on an image captured by the imaging device S6. Next, the maximum loading amount detection unit 62 detects the maximum loading amount of the dump truck based on the identified image of the dump truck. For example, the maximum load detection unit 62 determines the vehicle type (size, etc.) of the dump truck based on the image of the specified dump truck. The maximum loading amount detection unit 62 has a table that associates vehicle types with maximum loading amounts, and calculates the maximum loading amount of the dump truck based on the vehicle type and table determined from the image. Note that the maximum loading capacity, vehicle type, etc. of the dump truck may be input through the input device 42, and the maximum loading amount detection section 62 may calculate the maximum loading capacity of the dump truck based on the input information from the input device 42.

The additional loading amount calculation unit 63 calculates the weight of earth and sand loaded on the dump truck. That is, each time the earth and sand in the bucket 6 is dumped onto the bed of a dump truck, the additional load amount calculation unit 63 adds the weight of earth and sand in the bucket 6 calculated by the load weight calculation unit 61, and The additional loading amount (total weight), which is the total weight of earth and sand loaded on the truck bed, is calculated. Note that when the target dump truck for loading earth and sand becomes a new dump truck, the additional loading amount is reset.

The remaining load amount calculation section 64 calculates the difference between the maximum load amount of the dump truck detected by the maximum load amount detection section 62 and the current additional load amount calculated by the additional load amount calculation section 63 as the remaining load amount. The remaining load is the remaining weight of earth and sand that can be loaded on the dump truck.

The loaded object gravity center calculation unit 65 calculates the gravity center of the earth and sand (loaded object) in the bucket 6. For example, the load center of gravity calculation unit 65 assumes that the positional relationship between the toe position of the bucket 6 and the center of gravity of the earth and sand is known, and calculates the position based on the values of the boom angle sensor S1, arm angle sensor S2, bucket angle sensor S3, etc. , the center of gravity of the sediment may be calculated. Note that the calculation method is not limited to this, and various methods can be used.

The display device 40 displays the earth and sand weight in the bucket 6 calculated by the load weight calculation unit 61, the maximum load of the dump truck detected by the maximum load detection unit 62, and the weight calculated by the additional load calculation unit 63. The additional loading capacity of the dump truck (the total weight of the earth and sand loaded on the loading platform) and the remaining loading capacity of the dump truck (the remaining weight of the earth and sand that can be loaded) calculated by the remaining loading capacity calculation unit 64 may be displayed. .

Note that the display device 40 may be configured to issue a warning when the additional loading amount exceeds the maximum loading amount. Furthermore, if the calculated weight of earth and sand in the bucket 6 exceeds the remaining loading capacity, the display device 40 may be configured to issue a warning. Note that the warning is not limited to being displayed on the display device 40, and may be an audio output from the audio output device 43. This can prevent earth and sand from being loaded in excess of the maximum loading capacity of the dump truck.

[Sediment weight calculation method in first weight calculation unit 611]
Next, a method for calculating the weight of the earth and sand (loaded object) in the bucket 6 in the first weight calculation unit 611 of the excavator 100 according to the present embodiment will be described using FIG. 6 with reference to FIG. 5 .

FIG. 6 is a schematic diagram illustrating parameters related to calculating the earth and sand weight in the attachment of the shovel 100. 6(a) shows the excavator 100, and FIG. 6(b) shows the vicinity of the bucket 6. In addition, in the following description, it is demonstrated that the pin P1 mentioned later, the bucket gravity center G3, and the earth and sand gravity center Gs are arrange|positioned on the horizontal line L1.

Here, the pin connecting the upper revolving structure 3 and the boom 4 is designated as P1. The pin connecting the upper revolving structure 3 and the boom cylinder 7 is designated as P2. The pin that connects the boom 4 and the boom cylinder 7 is designated as P3. A pin connecting the boom 4 and the arm cylinder 8 is designated as P4. A pin connecting arm 5 and arm cylinder 8 is designated as P5. The pin that connects the boom 4 and the arm 5 is designated as P6. The pin connecting the arm 5 and the bucket 6 is designated P7. Furthermore, the center of gravity of the boom 4 is assumed to be G1. Let the center of gravity of arm 5 be G2. Let G3 be the center of gravity of the bucket 6. Let Gs be the center of gravity of the earth and sand (loaded material) loaded in the bucket 6. The reference line L2 is a line that passes through the pin P7 and is parallel to the opening surface of the bucket 6. Further, the distance between the pin P1 and the center of gravity G4 of the boom 4 is assumed to be D1. Let D2 be the distance between pin P1 and center of gravity G5 of arm 5. Let D3 be the distance between the pin P1 and the center of gravity G6 of the bucket 6. Let Ds be the distance between the pin P1 and the center of gravity Gs of the earth and sand. Let Dc be the distance between the straight line connecting pins P2 and P3 and pin P1. Further, the detected value of the cylinder pressure of the boom cylinder 7 is assumed to be Fb. Further, the vertical component of the boom weight in the direction perpendicular to the straight line connecting the pin P1 and the boom center of gravity G1 is defined as W1a. Of the arm weight, the vertical component in the direction perpendicular to the straight line connecting the pin P1 and the arm center of gravity G2 is defined as W2a. Let W6 be the weight of the bucket 6, and let Ws be the weight of the earth and sand (loaded material) loaded in the bucket 6.

As shown in FIG. 6(a), the position of pin P7 is calculated from the boom angle and arm angle. That is, the position of pin P7 can be calculated based on the detected values of boom angle sensor S1 and arm angle sensor S2.

Further, as shown in FIG. 6(b), the positional relationship between pin P7 and bucket center of gravity G3 (angle θ4 between reference line L2 of bucket 6 and a straight line connecting pin P7 and bucket center of gravity G3; pin P7 and bucket center of gravity The distance D4 from G3) is a specified value. Further, the positional relationship between the pin P7 and the center of gravity Gs of the earth and sand (angle θ5 between the reference line L2 of the bucket 6 and the straight line connecting the pin P7 and the center of gravity Gs of the earth and sand; the distance D5 between the pin P7 and the center of gravity Gs of the earth and sand) is, for example, , is experimentally determined in advance and stored in the controller 30. That is, the earth and sand gravity center Gs and the bucket gravity center G3 can be estimated based on the bucket angle sensor S3.

That is, the loaded object gravity center calculation unit 65 can estimate the earth and sand gravity center Gs based on the detected values of the boom angle sensor S1, the arm angle sensor S2, and the bucket angle sensor S3.

Next, the equation of balance between each moment around the pin P1 and the boom cylinder 7 can be expressed by the following equation (1).

WsDs+W1aD1+W2aD2+W3D3=FbDc...(1)

When formula (1) is expanded for the soil weight Ws, it can be expressed as the following formula (2).

Ws=(FbDc-(W1aD1+W2aD2+W3D3))/Ds...(2)

Here, the detected value Fb of the cylinder pressure of the boom cylinder 7 is calculated by the boom rod pressure sensor S7R and the boom bottom pressure sensor S7B. The distance Dc and the vertical component weight W1a are calculated by the boom angle sensor S1. The vertical component weight W2a and distance D2 are calculated by the boom angle sensor S1 and the arm angle sensor S2. The distance D1 and the weight W3 are known values. Further, by estimating the sediment gravity center Gs and the bucket gravity center G3, the distance Ds and the distance D3 are also estimated.

Therefore, the earth and sand weight Ws is determined by the detected value of the cylinder pressure of the boom cylinder 7 (the detected value of the boom rod pressure sensor S7R and the boom bottom pressure sensor S7B), the boom angle (the detected value of the boom angle sensor S1), and the arm angle (the detected value of the boom angle sensor S1). It can be calculated based on the detection value of sensor S2). Thereby, the loaded object weight calculation section 61 can calculate the earth and sand weight Ws based on the earth and sand gravity center Gs estimated by the loaded object gravity center calculation section 65.

Note that whether or not the excavator 100 is in the specified operation can be determined by estimating the attitude of the attachment based on the detection value of the pilot of the bucket cylinder 9.

Although the description has been made assuming that the attitude of the bucket 6 during the specified operation is horizontal, the center of gravity of the earth and sand is estimated, and the weight of the earth and sand is calculated, the present invention is not limited to this. For example, the bucket 6 may be imaged by a camera S6F that images the front, and the attitude of the bucket 6 may be estimated based on the image. Alternatively, the bucket 6 may be imaged by the camera S6F, and based on the image, when it is determined that the attitude of the bucket 6 is horizontal, the center of gravity of the earth and sand may be estimated and the earth and sand load may be calculated. Here, when performing crane work in crane mode, it is necessary to find the center of gravity of the suspended load as the center of gravity of earth and sand. In this case, since the hook 6e is usually arranged on the connecting pin 9d, the weight of the suspended load can be calculated by setting the center of gravity of the earth and sand (loaded object) Gs as the position of the connecting pin 9d. Furthermore, since the bucket 6 is in a closed state during crane work, the weight of the suspended load is calculated based on the center of gravity Ge of the bucket 6 when the bucket 6 is closed.

[Sediment weight calculation method in second weight calculation unit 612]
Next, a method of calculating the weight of the earth and sand (loaded object) in the bucket 6 in the second weight calculating section 612 of the excavator 100 according to the present embodiment will be described.

Here, the equation of motion of the turning torque τ when turning the upper rotating structure 3 can be expressed by the following equation (3). Note that the attachment angle θ includes a boom angle, an arm angle, and a bucket angle.

Furthermore, the equation of motion of the turning torque τ0 when turning the upper rotating structure 3 when there is no earth and sand in the bucket 6 (in the case of an empty load) can be expressed by the following equation (4).

Further, the equation of motion of the turning torque τw when turning the upper rotating body 3 when there is earth and sand in the bucket 6 can be expressed by the following equation (5).

Here, from equations (4) and (5), the difference Δτ between the turning torque τw when there is earth and sand and the turning torque τ0 when there is no earth and sand can be expressed by the following equation (6).

Here, since the parameters other than the loaded object weight M in equation (6) are known or measurable, the loaded object weight M can be calculated.

That is, the second weight calculation unit 612 acquires the turning driving force of the rotating upper structure 3 during the turning operation of the rotating upper structure 3. Here, the swing driving force of the upper swing structure 3 is obtained from the pressure difference between one port and the other port of the swing hydraulic motor 2A, that is, the difference in oil pressure detected by the oil pressure sensors 21 and 22.

Further, the second weight calculation unit 612 acquires the posture of the attachment using a posture sensor. For example, the attachment angle (boom angle, arm angle, bucket angle) is acquired by the boom angle sensor S1, arm angle sensor S2, and bucket angle sensor S3. Further, the inclination angle of the aircraft body may be acquired by the aircraft inclination sensor S4. Further, the second weight calculation unit 612 obtains the turning angular velocity and turning angle of the upper rotating body 3 using the turning state sensor S5.

Further, the second weight calculation unit 612 has a table in advance. A load weight M is associated with the table in correspondence with the attitude of the attachment and the swing driving force.

Thereby, the second weight calculation unit 612 can calculate the weight M of the loaded object based on the swing driving force, information from the attitude sensor, and the table.

Further, the second weight calculation unit 612 may calculate the turning inertia using the turning driving force, and calculate the loaded object weight M based on the obtained turning inertia.

Here, the turning inertia when there is no earth and sand in the bucket 6 can be determined from the attitude of the attachment and known information (center of gravity position, weight, etc. of each part). Moreover, the turning inertia when there is earth and sand in the bucket 6 can be calculated from the turning torque.

The amount of increase in the turning inertia when there is no earth and sand to the turning inertia when there is earth and sand is based on the weight of earth and sand in the bucket 6. Therefore, the weight M of the loaded object can be calculated by comparing the turning inertia when there is no earth and sand and the turning inertia when there is earth and sand. In other words, the weight M of the loaded object can be calculated based on the difference between these turning inertias.

Here, the swing driving force includes the influence of the moment of inertia and the swing centrifugal force. Therefore, the method of calculating the earth and sand weight in the second weight calculation unit 612 does not require complicated compensation when calculating the weight of the loaded object, and can directly determine the weight M of the loaded object.

In addition, although the excavator 100 has been described using an example in which the upper revolving body 3 rotates, the present invention is not limited to this. For example, when the upper revolving body 3 rotates and the attachment has a velocity component in a direction other than the rotation direction, the weight M of the loaded object may be determined by taking the velocity of the attachment into consideration. For example, when the bucket 6 moves in a direction away from or closer to the rotation axis of the upper revolving structure 3, or in an upward or downward direction along the rotation axis of the upper revolving structure 3, the speed of the bucket 6 is The weight M of the loaded object may be calculated taking this into account.

[Sediment weight calculation method in third weight calculation unit 613]
Next, a method for calculating the weight of earth and sand (loaded object) in the bucket 6 in the third weight calculation unit 613 of the excavator 100 according to the present embodiment will be described using FIG. 7 with reference to FIG. 5 .

FIG. 7 is a partially enlarged view illustrating the relationship of forces acting on the bucket 6. Moreover, FIG. 7(A) shows a case where the shape of the earth and sand in the bucket 6 is the first shape (standard shape). FIG. 7(B) shows a case where the shape of the earth and sand in the bucket 6 is the second shape (an example of the shape when measuring the weight of earth and sand).

As shown in FIG. 7(A), the rear end side of the bucket cylinder 9 is connected to the vicinity of the rear end of the arm 5 by a connecting pin 9a. The tip side of the bucket cylinder 9 is connected to one ends of two links 91 and 92 by a connecting pin 9b. One end of the link 91 is connected to the tip of the bucket cylinder 9 by a connecting pin 9b, and the other end is connected to the vicinity of the tip of the arm 5 by a connecting pin 9c. One end of the link 92 is connected to the distal end of the bucket cylinder 9 by a connecting pin 9b, and the other end is connected to the vicinity of the proximal end of the bucket 6 by a connecting pin 9d.

Further, as shown in FIG. 7(A), L1 is the horizontal distance between the center of gravity Ge of the bucket 6 and the center of the bucket support shaft 6b. L2 is the horizontal distance between the center of gravity Gl of the earth and sand L in the bucket 6 and the center of the bucket support shaft 6b. L3 is the distance between a line segment passing through the center of the connecting pin 9a and the center of the connecting pin 9b (the central axis of the bucket cylinder 9) and the center of the connecting pin 9c. L4 is the distance between a line segment passing through the center of the connecting pin 9b and the center of the connecting pin 9d (the central axis of the link 92) and the center of the connecting pin 9c. L5 is the distance between a line segment passing through the center of the connecting pin 9b and the center of the connecting pin 9d (the central axis of the link 92) and the center of the bucket support shaft 6b.

When the bucket 6 of the excavator 100 is maintained in a predetermined load holding posture regardless of the inclination angle of the arm 5, for example, in a predetermined horizontal posture such that the bucket tip 6a is at the same height as the bucket support shaft 6b, the bucket support A moment M due to the weight of the bucket 6 and a moment due to the reaction force F of the bucket cylinder 9 that maintains the bucket 6 in the load holding attitude act around the shaft 6b. Since the bucket 6 is balanced in this state, the two moments are opposite in direction and equal in magnitude due to the balance condition.

The moment M due to the weight of the bucket 6 side is divided into a moment Me due to the weight We of the bucket 6, and a moment Ml due to the weight Wl of the earth and sand L, so it can be expressed by the following equation (7).

M=Me+Ml...(7)

Next, the moment due to the reaction force F of the bucket cylinder 9 that maintains the bucket 6 in the load holding posture will be explained. First, if the moment given by the reaction force F of the bucket cylinder 9 around the center of the connecting pin 9c of the link 91 is mc, it can be expressed by the following equation (8-1).

mc=F・L3...(8-1)

On the other hand, the link 91 and the link 92 are rotatably connected at the center of the connecting pin 9b, and if the reaction force acting from the connecting pin 9b of the link 92 in the direction of the connecting pin 9d is fbd, then the reaction force around the center of the connecting pin 9c is From the balance with the moment mc, it can be expressed by the following equation (8-2).

fbd・L4=mc...(8-2)

Furthermore, around the center of the bucket support shaft 6b, the reaction force fcd acting on the center of the connecting pin 9d and the moment M of the bucket 6 are balanced, so it can be expressed by the following equation (8-3).

fcd・L5=M…(8-3)

When formulas (8-1) to (8-3) are rearranged, the balance formula can be expressed as the following formula (8).

F・L3・L5/L4=M…(8)

Here, when the bucket 6 is maintained in a predetermined load holding posture, the positions of the connecting pins 9a to 9d relative to the position of the bucket support shaft 6b are determined by the posture sensor (for example, boom angle sensor S1, arm angle sensor S2, bucket angle sensor S3, body tilt sensor S4, and turning state sensor S5), and the distances L3, L4, and L5 can be determined.

Further, if the load pressure detected based on the pressure sensor (for example, bucket rod pressure sensor S9R, bucket bottom pressure sensor S9) of the bucket cylinder 9 is P, and the pressure receiving area of the piston of the bucket cylinder 9 is S, then the bucket cylinder 9 The reaction force F can be expressed by the following equation (9).

F=P×S…(9)

As described above, based on the detected values of the attitude sensor and the pressure sensor of the bucket cylinder 9, the moment due to the reaction force F of the bucket cylinder 9 can be determined using equations (8) and (9).

On the other hand, the moment Me due to the weight We of the bucket 6 can be expressed by the following equation (10). Further, the moment Ml due to the weight Wl of the earth and sand L can be expressed by the following equation (11).

Me=We×L1…(10)
Ml=Wl×L2…(11)

Note that when the bucket 6 is maintained in a predetermined load holding posture, the distance L1 can be determined by the posture sensor. Note that the distance L2 is, for example, experimentally determined in advance and stored in the controller 30. Alternatively, the distance L2 may be calculated based on the center of gravity of the earth and sand calculated by a loaded object center of gravity calculation unit 65, which will be described later.

As described above, based on the detected values of the attitude sensor and the pressure sensor of the bucket cylinder 9, the weight Wl of the earth and sand L can be determined using equations (7) to (11). In addition, although the case where the earth and sand weight is calculated|required based on the pressure of the bucket cylinder 9 was demonstrated as an example, it is not limited to this. For example, the weight Wl of the earth and sand L may be determined based on the detected values of the attitude sensor and the pressure sensor of the boom cylinder 7. Furthermore, the weight Wl of the earth and sand L may be determined based on the detected values of the posture sensor and the pressure sensor of the arm cylinder 8. Incidentally, the relational expressions in these cases may be obtained in the same manner, and the explanation thereof will be omitted.

[Sediment weight calculation method]
Next, a method for calculating the weight of the earth and sand (loaded object) in the bucket 6 in the first weight calculation unit 611 that calculates the earth and sand weight based on the thrust of the boom cylinder 7 will be explained using FIG. 8 .

FIG. 8 is a block diagram illustrating the processing of the first weight calculation unit 611. The first weight calculation section 611 includes a torque calculation section 71 , an inertial force calculation section 72 , a centrifugal force calculation section 73 , a static torque calculation section 74 , and a weight conversion section 75 .

The torque calculation unit 71 calculates the torque around the foot pin of the boom 4 (detected torque). It is calculated based on the pressure of hydraulic oil in the boom cylinder 7 (boom rod pressure sensor S7R, boom bottom pressure sensor S7B).

The inertia force calculation unit 72 calculates the torque (inertia term torque) around the foot pin of the boom 4 due to the inertia force. The inertia term torque is calculated based on the angular acceleration of the boom 4 around the foot pin and the inertia moment of the boom 4. The angular acceleration and moment of inertia around the foot pin of the boom 4 are calculated based on the output of the attitude sensor.

The centrifugal force calculation unit 73 calculates the torque (centrifugal term torque) around the foot pin of the boom 4 due to Coriolis and centrifugal force. The centrifugal torque is calculated based on the angular velocity of the boom 4 around the foot pin and the weight of the boom 4. The angular velocity of the boom 4 around the foot pin is calculated based on the output of the attitude sensor. The weight of boom 4 is known.

The stationary torque calculation unit 74 calculates the torque around the foot pin of the boom 4 when the attachment is stationary, based on the detected torque of the torque calculation unit 71, the inertial term torque of the inertia force calculation unit 72, and the centrifugal term torque of the centrifugal force calculation unit 73. The static torque τW is calculated. Here, the equation for the torque around the foot pin of the boom 4 is shown in equation (12). Note that τ on the left side of equation (12) indicates the detected torque, the first term on the right side indicates the inertial term torque, the second term on the right side indicates the centrifugal term torque, and the third term on the right side indicates the static torque τW. show.

As shown in equation (12), the static torque τW can be calculated by subtracting the inertial term torque and the centrifugal term torque from the detected torque τ. Thereby, in this embodiment, it is possible to compensate for the influence caused by the rotational movement of the boom or the like around the pin.

The weight conversion unit 75 calculates the earth and sand weight Wl based on the static torque τW. The earth and sand weight W1 can be calculated, for example, by subtracting the torque when no earth and sand is loaded in the bucket 6 from the static torque τW, and dividing the torque by the horizontal distance from the foot pin of the boom 4 to the center of gravity of the earth and sand.

In this way, the first weight calculation unit 611 can calculate the earth and sand weight by compensating for the inertial term and the centrifugal term during the operation of the boom 4. Although the description will be omitted, the third weight calculation unit 613 may similarly calculate the earth and sand weight by compensating for the inertial term and the centrifugal term during the operation of the bucket 6. Here, when performing crane work in crane mode, it is necessary to find the center of gravity of the suspended load as the center of gravity of earth and sand. In this case, since the hook 6e is usually arranged on the connecting pin 9d, the weight of the suspended load can be calculated by setting the center of gravity of the earth and sand (loaded object) Gs as the position of the connecting pin 9d. Furthermore, since the bucket 6 is in a closed state during crane work, the weight of the suspended load is calculated based on the center of gravity Ge of the bucket 6 when the bucket 6 is closed.

[Vibration control in crane mode]
The excavator 100 according to the present embodiment has a crane mode in which a suspended load 800 is lifted with the hook 6e as a working mode.

For example, the operator shifts to the crane mode by operating the mode changeover switch 42a. In the crane mode, the rotation speed of the engine 11 is set to a predetermined rotation speed. Specifically, in the crane mode, the rotation speed of the engine 11 is set to be lower than the rotation speed of the engine 11 in the normal mode in which excavation work is performed. Further, the opening operation of the bucket 6 is restricted. For example, the controller 30 closes the proportional valve 33BR (see FIG. 4(B)) so that even if the lever device 26B is operated to open the bucket 6, the pilot pressure does not reach the control valve 174. There is.

The controller 30 has a suspended load vibration detection section that detects vibrations of the suspended load 800. In other words, the suspended load vibration detection section detects a change in the center of gravity position of the suspended load 800. Further, the suspended load vibration detection unit calculates the vibration period, swing angle, etc. of the suspended load 800 as information on the change in the center of gravity position of the suspended load 800. Here, if the hanging load 800 is shaking, it is unstable. Therefore, if the lifting operation is continued by the boom raising operation, there is a risk that the suspended load 800 will collapse.

FIG. 9 is a conceptual diagram illustrating the vibration damping control of this embodiment, FIG. 9(a) is a conceptual diagram showing the vibration of a suspended load, and FIG. It is a conceptual diagram showing operation. In addition, the direction away from the cabin 10 will be described as the x direction. Moreover, the center of gravity position of the suspended load 800 is illustrated by a black circle. FIG. 10 is a graph showing the relationship between the position of the hook 6e and the position of the center of gravity of the suspended load 800. FIG. 10(a) is an example in which the suspended load 800 vibrates, and FIG. This is an example of vibration damping control. In addition, in FIG. 10, the center of gravity position (x direction) of the hanging load 800 is shown by a solid line, and the position (x direction) of the hook 6e is shown by a broken line.

When the position of the hook 6e is kept stationary, the vibration of the suspended load 800 becomes free vibration as shown in FIG. 10(a). Therefore, as shown in FIG. 9(a), the hanging load 800 swings between the position 800a and the position 800b.

Here, if the suspended load 800 moves toward the position 800a (in other words, in the direction away from the cabin 10), the torque around the foot pin of the boom 4 increases. Further, if the suspended load 800 moves toward the position 800b (in other words, toward the cabin 10), the torque around the foot pin of the boom 4 decreases. The suspended load vibration detection unit calculates the torque around the foot pin of the boom 4 based on the detected values of the boom rod pressure sensor S7R and the boom bottom pressure sensor S7B, and detects the suspended load 800 based on the change in the calculated torque. Detects changes in the center of gravity position.

For example, the suspended load vibration detection unit obtains the vibration period T ₀ of the suspended load 800 based on the vibration period of the torque around the foot pin of the boom 4 . Further, the suspended load vibration detection unit calculates the length from the hook 6e to the center of gravity of the suspended load 800 based on the vibration period _T0 of the suspended load 800.

Further, based on the median value (for example, average value) of torque vibration, the torque when the suspended load 800 is not vibrating (static torque) can be acquired. Here, the earth and sand load processing section 60 can calculate the weight of the suspended load in the crane mode as well as in the case of the excavation operation (normal mode). Here, the earth and sand load processing unit 60 can calculate the weight of the suspended load 800 based on the static torque assuming that the center of gravity of the suspended load 800 is directly below the hook 6e.

Further, the earth and sand load processing section 60 can calculate the center of gravity position of the suspended load 800 based on the calculated weight of the suspended load 800 and the torque around the foot pin of the boom 4. That is, the suspended load vibration detection unit can calculate the amplitude X ₀ of the vibration of the suspended load 800. Further, the suspended load vibration detection unit can calculate the angle of vibration of the suspended load 800 based on the position of the center of gravity of the suspended load 800 and the length from the hook 6e to the center of gravity of the suspended load 800.

Note that the method of detecting a change in the center of gravity position of a suspended load by the suspended load vibration detection section is not limited to this. The suspended load vibration detection unit may detect a change in the center of gravity position of the suspended load 800 based on the image of the bucket 6 and the suspended load 800 captured by the camera S6F.

The controller 30 performs vibration damping control on the attachments (boom 4, arm 5) based on the change in the center of gravity position of the suspended load 800 (amplitude X ₀ , period T ₀ , angle of vibration) detected by the suspended load vibration detection unit. . Specifically, as shown in FIG. 9(b), the attachments (boom 4, arm 5) are moved so that the hook 6e moves directly above the center of gravity of the suspended load 800 at the timing when the amplitude of the suspended load 800 becomes maximum. control. Thereby, as shown in FIG. 10(b), the vibration of the hanging load 800 can be reduced.

Note that the attachment control in the damping control may be performed by the movement of the arm 5 (in the example shown in FIG. 9(b), the opening movement of the arm 5). By operating the arm 5, the hook 6e can be moved directly above the center of gravity of the hanging load 800.

Further, the attachment control in vibration damping control may be performed by the operation of the arm 5 and the boom 4 (in the example shown in FIG. 9(b), the opening operation of the arm 5 and the lowering operation of the boom 4). By operating the arm 5 and the boom 4, the hook 6e can be moved directly above the center of gravity of the hanging load 800, and the hook 6e can be moved horizontally. When the amplitude of the vibration of the suspended load 800 falls within a predetermined range, the center of gravity of the suspended load 800 may be calculated based on the attitude of the attachment at that time, and the suspended load 800 may be calculated. In this case, since the influence of shaking is reduced, the weight of the hanging load 800 can be calculated accurately. Furthermore, since the shaking of the suspended load 800 can be quickly contained, the weight can be calculated quickly.

As described above, according to the excavator 100 according to the present embodiment, vibration of the suspended load 800 can be suppressed in the crane mode. Further, according to the shovel 100 according to the present embodiment, the vibration of the suspended load 800 can be suppressed without providing a sensor or the like for detecting vibration to the suspended load 800.

Although the embodiments of the shovel 100 have been described above, the present invention is not limited to the above embodiments, etc., and various modifications and improvements can be made within the scope of the gist of the present invention as described in the claims. is possible.

If a person is detected within a predetermined range around the excavator 100 by the space recognition device (imaging device S6), the controller 30 performs an operation to raise the suspended load 800 (a lifting operation of the boom 4) even if the lever device is operated. etc.) may be prevented from starting.

Further, the controller 30 may include a suspended load vibration detection unit that detects the shaking of the suspended load 800 lifted by the hook 6e. The suspended load vibration detection unit may detect the shaking of the suspended load 800, for example, based on the detected values of the boom rod pressure sensor S7R and the boom bottom pressure sensor S7B. Further, for example, the shaking of the hanging load 800 may be detected by a space recognition device (imaging device S6).

Further, when the suspended load 800 is shaking, a worker may enter around the suspended load 800 in order to stop the suspended load 800 from shaking. If a person is detected within a predetermined range around the excavator 100 (or the suspended load) by the space recognition device (imaging device S6) while the shaking of the suspended load 800 is being measured, the controller 30 determines whether the work It may also be configured to notify the person or operator of a warning or other alert.

100 Shovel 1 Lower traveling body 2 Swing mechanism 3 Upper rotating body 4 Boom (attachment)
5 Arm (attachment)
6 Bucket (attachment)
6e Hook 7 Boom cylinder 8 Arm cylinder 9 Bucket cylinder 30 Controller (control device)
40 Display device 42 Input device 42a Mode changeover switch 43 Audio output device 47 Storage device 60 Sediment load processing section (weight detection section)
S1 Boom angle sensor S2 Arm angle sensor S3 Bucket angle sensor S4 Aircraft tilt sensor S5 Turning state sensor S6 Imaging device

Claims (6)

An attachment having a hook for hanging a suspended load;
a suspended load vibration detection unit that detects a change in the center of gravity position of the suspended load due to vibration;
A control unit that controls the attachment,
The suspended load vibration detection section is
detecting the amplitude of the center of gravity position of the suspended load, the period of vibration of the suspended load, and the angle of vibration of the suspended load;
The control unit includes:
By controlling the attachment, the amplitude of the center of gravity position of the suspended load detected by the suspended load vibration detection unit, the period of vibration of the suspended load, with respect to the shaking of the suspended load when the suspended load cuts off the ground, and an excavator that controls the attachment to perform vibration damping control on the suspended load based on the angle of vibration of the suspended load. the attachment has a boom;
The shovel is
a boom cylinder that drives the boom;
a torque calculation unit that calculates torque around the foot pin of the boom based on the pressure of hydraulic oil in the boom cylinder;
further comprising a weight detection unit that detects the weight of the suspended load ,
The weight detection section is
obtaining a static torque of the suspended load based on a median value of torque vibrations around the foot pin of the boom;
Calculating the weight of the suspended load based on the static torque of the suspended load,
The suspended load vibration detection section is
Obtaining the period of vibration of the suspended load based on the period of vibration of torque around the foot pin of the boom,
Calculating the length from the hook to the center of gravity of the suspended load based on the period of vibration of the suspended load,
Calculating the center of gravity position of the suspended load based on the weight of the suspended load and the torque around the foot pin of the boom,
Calculating the amplitude of the center of gravity position of the hanging load from the center of gravity position of the hanging load,
Calculating the angle of vibration of the suspended load based on the position of the center of gravity of the suspended load and the length from the hook to the center of gravity of the suspended load;
The excavator according to claim 1. The control unit includes:
controlling the attachment so that the hook is located above the center of gravity of the suspended load;
The excavator according to claim 1 or claim 2 . The control unit includes:
controlling the attachment so that the hook is located above the center of gravity of the suspended load at a timing when the amplitude of the suspended load is maximum;
The excavator according to claim 3 . The attachment has at least an arm,
The control unit controls the arm so that the hook is located above the center of gravity of the suspended load.
The excavator according to claim 3 or 4 . The attachment has at least a boom and an arm,
The control unit controls the boom and the arm so that the hook moves horizontally and is located above the center of gravity of the suspended load.
The excavator according to claim 3 or 4 .

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