Working machine

Abstract

To provide a work machine capable of suppressing a decrease in work efficiency even when an abnormality occurs.SOLUTION: When a predetermined abnormality occurs, a work machine according to one embodiment performs, while continuing the operation of own machine, at least one of giving a notification to an operator to urge the operator to suppress an operation of the own machine and automatically shifting to a state in which the operation of the own machine with respect to the operation input is limited. Moreover, when a predetermined abnormality occurs, the work machine according to another embodiment continues the operation while limiting the operation thereof, and thereafter releases the operation limitation. Further, the work machine according to still another embodiment tries to recover from the predetermined abnormality while the predetermined abnormality continues the normal operation of the own machine. Further, the work machine according to yet another embodiment continues the normal operation of the own machine when the predetermined abnormality occurs, and thereafter limits the operation stepwise according to the state of the own machine.SELECTED DRAWING: Figure 3A

Description

Technical Field

[0001] The present invention relates to a working machine.

Background Art

[0002] For example, working machines such as excavators are known (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when an abnormality occurs in the working machine, its operation may stop. Therefore, even in the case of a recoverable abnormality, during the period from recovering from the abnormality through the recovery work after the operation stops, restarting the working machine, and resuming the work, the work cannot be performed, and the work efficiency decreases.

[0005] Therefore, in view of the above problems, an object of the present invention is to provide a working machine capable of suppressing a decrease in work efficiency even when an abnormality occurs.

Means for Solving the Problems

[0006] To achieve the above object, in one embodiment of the present invention, Equipped with a control device, The control device is, when a predetermined abnormality occurs, a working machine while continuing the operation of , operation automatically shift to a state where the operation of a working machine in response to the work input is restricted, , together with the front attempt to recover from the specified predetermined abnormality, and as a result of the attempt, if successful in recovering from the predetermined abnormality, of the working machineWhen the operation restriction is released and the return from the predetermined abnormality fails, of the working machine stop the operation, a working machine is provided.

[0007] Also, in another embodiment of the present invention, Equipped with a control device, The control device is, When a predetermined abnormality occurs, a working machine while continuing the operation while restricting the operation of, attempt to return from the predetermined abnormality, and then, if the return from the predetermined abnormality is successful, of the working machine release the operation restriction, and if the return from the predetermined abnormality fails, of the working machine stop the operation, a working machine is provided.

[0008] Also, in still another embodiment of the present invention, Equipped with a control device, The control device is, When a predetermined abnormality occurs, a working machine while continuing the normal operation of, attempt to return from the predetermined abnormality, and as a result of that attempt, if the return from the predetermined abnormality fails, a working machine stop the operation of, a working machine is provided.

Advantages of the Invention

[0010] According to the above-described embodiment, even when an abnormality occurs, it is possible to provide a working machine capable of suppressing a decrease in work efficiency.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3A

Figure 3B

Figure 4A

Figure 4B

Figure 5

Mode for Carrying Out the Invention

[0012] Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings.

[0013] [First Example of Working Machine (Excavator)] First, with reference to FIGS. 1 to 3 (FIGS. 3A and 3B), an excavator as the first example of the working machine according to the present embodiment will be described.

[0014] <Outline of Excavator> First, with reference to FIG. 1, the outline of the excavator as the first example of the working machine will be described.

[0015] FIG. 1 is a side view showing the excavator according to the present embodiment.

[0016] The excavator according to the present embodiment includes a lower traveling body 1, an upper revolving body 3 mounted on the lower traveling body 1 so as to be revolvable via a slewing mechanism 2, a boom 4, an arm 5, and a bucket 6 as a working device, and a cabin 10 on which an operator rides.

[0017] The lower traveling body 1 includes, for example, a pair of left and right crawlers, and each crawler travels by being hydraulically driven by traveling hydraulic motors 1A and 1B (see FIG. 2).

[0018] The upper revolving body 3 revolves with respect to the lower traveling body 1 by being electrically driven by a slewing motor 21 (see FIG. 2) described later.

[0019] The boom 4 is pivotally attached to the center of the front part of the upper slewing body 3 so as to be able to pitch. At the tip of the boom 4, an arm 5 is pivotally attached so as to be able to rotate up and down. At the tip of the arm 5, a bucket 6 is pivotally attached so as to be able to rotate 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.

[0020] The cab 10 is mounted on the left side of the front part of the upper slewing body 3, and inside it, there are provided a driver's seat on which an operator sits, an operation device 26 described later, and the like.

[0021] <Configuration of the Excavator> Next, in addition to FIG. 1, with reference to FIG. 2, the configuration of the excavator according to the present embodiment will be described.

[0022] FIG. 2 is a block diagram showing an example of a configuration centered on the drive system of the excavator according to the present embodiment.

[0023] In the figure, the mechanical power line is shown as a double line, the high-pressure hydraulic line is shown as a thick solid line, the pilot line is shown as a broken line, and the electric drive / control line is shown as a thin solid line.

[0024] The hydraulic drive system of the excavator according to the present embodiment includes, as described above, travel hydraulic motors 1A and 1B that hydraulically drive the lower travel body 1, the boom 4, the arm 5, and the bucket 6 respectively, and hydraulic actuators such as the boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9. Further, the hydraulic drive system according to the present embodiment mainly includes an engine 11, an electric generator 12, a speed reducer 13, a main pump 14, and a control valve 17.

[0025] Note that the electric generator 12 will be described in detail in the part for explaining the electric drive system of the excavator.

[0026] The engine 11 (an example of a power source) is the main power source in the hydraulic drive system and is mounted on the rear part of the upper swing body 3. The engine 11 rotates at a constant speed at a predetermined target rotational speed under the control of an engine controller (ECM: Engine Control Module) 30C described later. The engine 11 is, for example, a diesel engine that uses light oil as fuel, and drives the main pump 14 and the pilot pump 15 via the reduction gear 13. Further, the engine 11 can drive the motor generator 12 via the reduction gear 13 and generate electricity in the motor generator 12.

[0027] The reduction gear 13 is mounted, for example, on the rear part of the upper swing body 3, and has two input shafts to which the engine 11 and the motor generator 12 described later are connected, and one output shaft to which the main pump 14 and the pilot pump 15 are coaxially connected in series. The reduction gear 13 can transmit the power of the engine 11 and the motor generator 12 to the main pump 14 and the pilot pump 15 at a predetermined reduction ratio. Further, the reduction gear 13 can distribute and transmit the power of the engine 11 to the motor generator 12 and the main pump 14 and the pilot pump 15 at a predetermined reduction ratio.

[0028] The main pump 14 (an example of a hydraulic pump) is mounted on the rear part of the upper swing body 3 and supplies hydraulic oil to the control valve 17 through the high-pressure hydraulic line 16. The main pump 14 is driven by the engine 11 or the engine 11 and the motor generator 12. The main pump 14 is, for example, a variable displacement hydraulic pump, and a regulator (not shown) controls the angle (tilt angle) of the swash plate under the control of a hydraulic excavator controller 30A described later. Thereby, the main pump 14 can adjust the stroke length of the piston and control the discharge flow rate (discharge pressure).

[0029] The control valve 17 is mounted on the central part of the upper swing body 3 and is a hydraulic control device that controls the hydraulic drive system in response to an operation input to the operation device 26 by the operator. As described above, the control valve 17 is connected to the main pump 14 via the high-pressure hydraulic line 16, and the hydraulic oil supplied from the main pump 14 can be supplied to the travel hydraulic motors 1A (for the right side), 1B (for the left side), the boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9 as hydraulic actuators. Specifically, the control valve 17 is a valve unit including a plurality of hydraulic control valves (direction change valves) that control the flow rate and flow direction of the hydraulic oil supplied from the main pump 14 to each of the hydraulic actuators.

[0030] The electric drive system of the excavator according to the present embodiment includes an electric generator 12, a current sensor 12s1, a voltage sensor 12s2, and an inverter 18A as components that assist the hydraulic drive system. Further, the electric drive system of the excavator according to the present embodiment includes a slewing motor 21, a current sensor 21s, a resolver 22, a mechanical brake 23, a slewing speed reducer 24, and an inverter 18B as components related to the electric drive of the driven element (specifically, the upper swing body 3).

[0031] The electric generator 12 (an example of a power source and an electric motor) is an assist power source for the hydraulic drive system and is mounted on the rear part of the upper swing body 3. The electric generator 12 is, for example, an IPM (Interior Permanent Magnet) motor. The electric generator 12 is connected to a power storage system 120 including a capacitor 19 and a swing electric motor 21 via an inverter 18A. The electric generator 12 performs a power running operation with three-phase AC power supplied from the capacitor 19 and the swing electric motor 21 via the inverter 18A, and drives the main pump 14 and the pilot pump 15 via a speed reducer 13 in a mode of assisting the engine 11. Further, the electric generator 12 performs a power generation operation by being driven by the engine 11, and can supply the generated electric power to the capacitor 19 and the swing electric motor 21. The switching control between the power running operation and the power generation operation of the electric generator 12 may be realized by the inverter 18A under the control of a hybrid controller (hereinafter, referred to as "HB controller") 30B described later.

[0032] The current sensor 12s1 detects the current of each of the three phases (U phase, V phase, W phase) of the electric generator 12. The current sensor 12s1 is provided, for example, in the power path between the electric generator 12 and the inverter 18A. Detection signals corresponding to the currents of the three phases of the swing electric motor 21 detected by the current sensor 12s1 are taken into the inverter 18A through a one-to-one communication line or a vehicle-mounted network such as a CAN (Controller Area Network). Further, the detection signal may be taken into the HB controller 30B once through a one-to-one communication line or a vehicle-mounted network such as a CAN, and input to the inverter 18A via the HB controller 30B. The same applies to the detection signal of the voltage sensor 12s2 hereinafter.

[0033] The voltage sensor 12s2 detects the applied voltage of each of the three phases of the electric generator 12. The current sensor 21s is provided, for example, in the power path between the electric generator 12 and the inverter 18A. Detection signals corresponding to the applied voltages of the three phases of the swing electric motor 21 detected by the voltage sensor 12s2 are taken into the inverter 18A through a one-to-one communication line or a vehicle-mounted network such as a CAN.

[0034] The inverter 18A controls the driving of the motor generator 12 under the control of the HB controller 30B. The inverter 18A includes, for example, a conversion circuit that converts DC power into three-phase AC power or converts three-phase AC power into DC power, a drive circuit that drives the conversion circuit by switching, and a control circuit that outputs a control signal (for example, a PWM (Pulse Width Modulation) signal) that defines the operation of the drive circuit.

[0035] Specifically, the control circuit of the inverter 18A may sequentially estimate the rotation angle and the like of the rotating shaft of the motor generator 12 based on the detection signals of the current sensor 12s1 and the voltage sensor 12s2. For example, the control circuit estimates the rotation angle, the rotation speed, and the like of the rotating shaft of the motor generator 12 based on, for example, a known Extended Electromotive Force (EEFM) model. Then, based on the estimated values of the rotation angle and the rotation speed sequentially derived, the control circuit may perform drive control of the motor generator 12 (hereinafter, "sensorless control") while grasping the operating state of the motor generator 12. As a result, it is not necessary to provide a predetermined sensor (for example, a rotary encoder or the like) for detecting the rotation angle and the rotation position in the motor generator 12. Therefore, mechanical sensors can be reduced, the cost of the excavator can be suppressed, and detection failures due to contamination of the sensors and the like can be suppressed.

[0036] Further, instead of the detected value of the applied voltage of the motor generator 12 by the voltage sensor 12s2, the control circuit of the inverter 18A may estimate the rotation angle of the rotation shaft of the motor generator 12 using the voltage command value of the motor generator 12 input from the HB controller 30B or generated by itself in the process of control. In this case, the voltage sensor 12s2 may be omitted. Further, the control circuit of the inverter 18A may control the motor generator 12 based on the detection signal of the sensor that detects the rotation angle of the motor generator 12. In this case, the motor generator 12 is equipped with a sensor that detects the rotation angle of the rotation shaft, such as a rotary encoder or a resolver. Further, at least one of the drive circuit and the control circuit of the inverter 18A may be provided outside the inverter 18A.

[0037] The slewing motor 21 is provided in the slewing mechanism 2 that connects the lower traveling body 1 and the upper slewing body 3, and under the control of the HB controller 30B, performs a power running operation that drives the upper slewing body 3 to slew and a regenerative operation that generates regenerative power to brake the upper slewing body 3. The slewing motor 21 is connected to the power storage system 120 via the inverter 18B and is driven by three-phase AC power supplied from the capacitor 19 or the motor generator 12 via the inverter 18B. Further, the slewing motor 21 supplies regenerative power to the capacitor 19 or the motor generator 12 via the inverter 18B. Thereby, the capacitor 19 can be charged or the motor generator 12 can be driven with the regenerative power. The switching control between the power running operation and the regenerative operation of the slewing motor 21 may be realized by the inverter 18B under the control of the HB controller 30B. A resolver 22, a mechanical brake 23, and a slewing speed reducer 24 are connected to the rotation shaft 21A of the slewing motor 21.

[0038] The current sensor 21s detects the current of each of the three phases (U-phase, V-phase, W-phase) of the swing motor 21. The current sensor 21s is provided, for example, in the power path between the swing motor 21 and the inverter 18B. The detection signals corresponding to the currents of the three phases of the swing motor 21, which are detected by the current sensor 21s, are directly taken into the inverter 18B through a one-to-one communication line or an in-vehicle network such as CAN. Further, the detection signal may be taken into the HB controller 30B through a one-to-one communication line or an in-vehicle network such as CAN, and input to the inverter 18B via the HB controller 30B.

[0039] The resolver 22 detects the rotational position (rotation angle) etc. of the swing motor 21. The detection signal corresponding to the rotation angle detected by the resolver 22 is taken into the HB controller 30B through a one-to-one communication line or an in-vehicle network such as CAN, and input to the inverter 18B via the HB controller 30B. Further, the detection signal may be directly taken into the inverter 18B.

[0040] The mechanical brake 23 mechanically generates a braking force on the rotating shaft 21A of the swing motor 21 under the control of the HB controller 30B. Thereby, the mechanical brake 23 can perform swing braking of the upper swing body 3 or maintain the stopped state of the upper swing body 3.

[0041] The swing speed reducer 24 is connected to the rotating shaft 21A of the swing motor 21, and increases the torque by reducing the output (torque) of the swing motor 21 at a predetermined reduction ratio to swing-drive the upper swing body 3. That is, during the power running operation, the swing motor 21 swing-drives the upper swing body 3 via the swing speed reducer 24. Further, the swing speed reducer 24 increases the inertial rotational force of the upper swing body 3 and transmits it to the swing motor 21 to generate regenerative power. That is, during the regenerative operation, the swing motor 21 performs regenerative power generation by the inertial rotational force of the upper swing body 3 transmitted via the swing speed reducer 24, and swing-brakes the upper swing body 3.

[0042] The inverter 18B drives and controls the swing motor 21 under the control of the HB controller 30B. The inverter 18B, for example, converts DC power into three-phase AC power or converts three-phase AC power into DC power. or the like It includes a conversion circuit that performs such conversions, a drive circuit that drives the conversion circuit by switching, and a control circuit that outputs a control signal (for example, a PWM signal) that defines the operation of the drive circuit.

[0043] Specifically, the control circuit of the inverter 18B performs speed feedback control and torque feedback control regarding the swing motor 21 based on the detection signals of the current sensor 21s and the resolver 22.

[0044] The power storage system 120 of the excavator according to this embodiment includes a capacitor 19, a buck-boost converter 100, and a DC bus 110. The power storage system 120 is mounted, for example, on the right front part of the upper swing body 3 together with the inverters 18A and 18B of the electric drive system.

[0045] The capacitor 19 is an example of a power storage device that supplies power to the motor generator 12 and the swing motor 21 and charges the generated power of the motor generator 12 and the swing motor 21. Also, a relay (hereinafter, "cut-off relay") that shuts off the connection between the capacitor 19 and the main circuit on the load side including the buck-boost converter 100 is provided. Thereby, the capacitor 19 is disconnected from the main circuit under the control of the HB controller 30B when the excavator stops or when an abnormality occurs in the excavator (for example, when an accident such as tipping occurs). Therefore, it is possible to suppress a situation in which an extremely large short-circuit current flows through the capacitor 19 due to an abnormality when the operator is absent or an abnormality when the operator is present. The cut-off relay is provided, for example, in both the positive and negative power paths between the capacitor 19 and the buck-boost converter 100.

[0046] The buck-boost converter 100 boosts the power of the capacitor 19 and outputs it to the DC bus 110, or steps down the power supplied to the DC bus 110 and stores it in the capacitor 19. The buck-boost converter 100 switches between the boost operation and the buck operation so that the voltage value of the DC bus 110 falls within a certain range according to the operating states of the motor generator 12 and the swing motor 21. The switching control of the boost operation and the buck operation of the buck-boost converter 100 may be realized by the HB controller 30B based on the voltage detection value of the DC bus 110, the voltage detection value of the capacitor 19, and the current detection value of the capacitor 19.

[0047] The DC bus 110 is provided between the inverters 18A and 18B and the buck-boost converter 100, and controls the power transfer between the capacitor 19, the motor generator 12, and the swing motor 21.

[0048] Also, the operation system of the excavator according to the present embodiment includes a pilot pump 15, an operating device 26, a pressure sensor 29, and the like.

[0049] The pilot pump 15 is mounted on the rear part of the upper swing body 3 and supplies pilot pressure to the operating device 26 via the pilot line 25. The pilot pump 15 is, for example, a fixed-displacement hydraulic pump and is driven by the engine 11, or the engine 11 and the motor generator 12.

[0050] The operating device 26 includes, for example, levers 26A and 26B, and a pedal 26C. The operating device 26 is provided near the driver's seat in the cabin 10, and is an operation input means for the operator to operate respective driven elements (for example, the lower traveling body 1, the upper swing body 3, the boom 4, the arm 5, and the bucket 6, etc.). In other words, the operating device 26 is an operation input means for operating hydraulic actuators (for example, traveling hydraulic motors 1A and 1B, boom cylinder 7, arm cylinder 8, bucket cylinder 9, etc.) and electric actuators (such as swing motor 21) that drive respective driven elements. The operating device 26 (levers 26A and 26B, and pedal 26C) is connected to the control valve 17 via a hydraulic line 27. Thereby, a pilot signal (pilot pressure) corresponding to the operating states of the lower traveling body 1, the boom 4, the arm 5, and the bucket 6, etc. in the operating device 26 is input to the control valve 17. Therefore, the control valve 17 can drive each hydraulic actuator according to the operating state in the operating device 26. Further, the operating device 26 is connected to a pressure sensor 29 via a hydraulic line 28.

[0051] As described above, the pressure sensor 29 is connected to the operating device 26 via the hydraulic line 28, and detects the pilot pressure on the secondary side of the operating device 26, that is, the pilot pressure corresponding to the operating states of respective operating elements in the operating device 26. The pressure sensor 29 is connected to the excavator controller 30A, and a pressure signal (pressure detection value) corresponding to the operating states of the lower traveling body 1, the upper swing body 3, the boom 4, the arm 5, and the bucket 6, etc. in the operating device 26 is taken into the excavator controller 30A.

[0052] The control system of the excavator according to the present embodiment includes a control device 30, another control target unit 40, and an HMI (Human Machine Interface) 50.

[0053] The control device 30 includes an excavator controller 30A, an HB controller 30B, and an engine controller 30C.

[0054] The excavator controller 30A, the HB controller 30B, the engine controller 30C, etc. may each have their functions realized by arbitrary hardware or a combination of hardware and software. For example, the excavator controller 30A, the HB controller 30B, the engine controller 30C, etc. may be centered around a microcomputer including a CPU (Central Processing Unit), a memory device (main memory device) such as a RAM (Random Access Memory), a non-volatile auxiliary storage device such as a ROM (Read Only Memory), an I / O (Input-Output) interface device, etc.

[0055] The excavator controller 30A cooperates with various controllers including the HB controller 30B and the engine controller 30C to perform drive control of the excavator. For example, the excavator controller 30A may integrally control the operation of the entire excavator (various devices mounted on the excavator) based on two-way communication with various controllers such as the HB controller 30B and the engine controller 30C.

[0056] The HB controller 30B performs drive control of the electric drive system based on various information input from the excavator controller 30A (for example, control commands including the detection value of the pressure sensor 29 corresponding to the operation state of the operation device 26). For example, the HB controller 30B drives the inverter 18A based on the detection value detected by the pressure sensor 29 corresponding to the operation state of the operation device 26, and performs switching control of the operation state (power running operation and power generation operation) of the motor generator 12. Also, for example, the HB controller 30B drives the inverter 18B based on the detection value detected by the pressure sensor 29 corresponding to the operation state of the operation device 26, and performs switching control of the operation state (power running operation and regeneration operation) of the slewing motor 21. Also, for example, the HB controller 30B drives the buck-boost converter 100 based on the detection value detected by the pressure sensor 29 corresponding to the operation state of the operation device 26, and performs switching control of the boost operation and the buck operation of the buck-boost converter 100, in other words, the discharge state and the charge state of the capacitor 19.

[0057] Further, the HB controller 30B may have a self-diagnosis function related to the electric drive system and detect various abnormalities related to the electric drive system.

[0058] Specifically, the HB controller 30B may detect an abnormality in the motor generator 12 or an abnormality related to the inverter 18A, that is, an abnormality related to the motor generator 12. For example, the HB controller 30B may monitor the temperature, current, voltage, etc. of the motor generator 12 and the inverter 18A to detect temperature abnormalities, current abnormalities (e.g., overcurrent), voltage abnormalities (e.g., overvoltage), etc. Further, the HB controller 30B may also detect abnormalities in components such as semiconductor switches, resistors, capacitors, and diodes of the inverter 18A.

[0059] The engine controller 30C performs drive control of the engine 11 based on various information input from the excavator controller 30A (e.g., control commands including the set rotational speed of the engine 11 and the operation mode of the excavator corresponding to the set rotational speed of the engine 11). Specifically, the engine controller 30C realizes drive control of the engine 11 by outputting control commands to actuators such as the starter motor and fuel injection device of the engine 11 to be controlled.

[0060] Further, the engine controller 30C may have a self-diagnosis function related to the engine 11 and detect various abnormalities related to the engine 11. For example, the engine controller 30C may detect abnormalities in various actuators such as the fuel injection device of the engine 11, abnormalities in various sensors such as the crank angle sensor, and abnormalities in the exhaust system.

[0061] The other controlled unit 40 is a component of the components to be controlled by the control device 30 related to the operation of the excavator, other than the components related to the motor generator 12 (specifically, the motor generator 12, the inverter 18A, etc.). For example, the other controlled unit 40 may include the engine 11, the inverter 18B that drives the slewing motor 21, etc. Further, for example, the other controlled unit 40 may include at least one of the main pump 14 of the hydraulic drive system, the control valve 17, and various valves (for example, a gate lock valve, a pressure reducing valve that adjusts the secondary pressure of the operating device 26, etc.) for controlling the control valve 17.

[0062] The HMI 50 is provided in the cab 10 and undertakes the interface function between the operator and the excavator. The HMI 50 includes notification (display) means (for example, an instrument panel including warning lights, a display, etc.) and operation means (for example, the operating device 26, the touch panel of the display, various buttons, switches, toggles, etc. arranged around the operator's seat).

[0063] <Operation of the Excavator When an Abnormality Occurs> Next, with reference to FIG. 3 (FIGS. 3A and 3B), the operation of the excavator when an abnormality occurs will be described.

[0064] FIGS. 3A and 3B are sequence diagrams showing specific examples of the operation of the excavator when a predetermined abnormality (an abnormality related to the motor generator 12) occurs. Specifically, FIG. 3A is a sequence diagram showing a specific example of the operation of the excavator when it can return to normal after the occurrence of a predetermined abnormality, and FIG. 3B is a sequence diagram showing a specific example of the operation of the excavator when it stops without being able to return to normal after the occurrence of a predetermined abnormality.

[0065] Note that since the processing of steps S102 to S118 is common in FIGS. 3A and 3B, for FIG. 3B, the description will be centered on the parts of the different processing (steps S130 to S138) from FIG. 3A. Also, the processing by the HB controller 30B in FIGS. 3A and 3B may be performed by the control circuit of the inverter 18A instead.

[0066] As shown in FIG. 3A, in step S102, the HB controller 30B detects an abnormality related to the motor generator 12 based on its self-diagnosis function.

[0067] In step S104, when an abnormality occurs in the motor generator 12, the HB controller 30B starts abnormal-time processing.

[0068] In step S106, the HB controller 30B transmits a notification indicating that an abnormality has occurred in the motor generator 12 (hereinafter referred to as "abnormality occurrence notification") to the excavator controller 30A, and in step S108, stops the motor generator 12 (that is, the inverter 18A). As a result, the transmission of assist power from the motor generator 12 to the main pump 14 and the supply of generated power from the motor generator 12 to the swing motor are stopped. That is, the excavator shifts to an operating state in which the main pump 14 is driven only by the power of the engine 11 and the swing motor 21 is driven only by the power from the power storage system (capacitor 19).

[0069] On the other hand, in step S110, when the excavator controller 30A receives the abnormality occurrence notification from the HB controller 30B, it transmits a notification (hereinafter referred to as "operation restriction notification") indicating that the operation of other controlled units 40 is to be restricted to the other controlled units 40 and the HMI 50. This is because the transmission of assist power from the motor generator 12 to the main pump 14 and the supply of generated power from the motor generator 12 to the swing motor 21 are stopped, and the response speed and maximum output of the main pump 14 and the swing motor 21 decrease. At this time, the operation restriction notification from the excavator controller 30A may be directly transmitted to the other controlled units 40 and the HMI 50 through a one-to-one communication line or a vehicle-mounted network such as CAN, or may be transmitted to the other controlled units 40 and the HMI 50 via another controller (for example, the engine controller 30C corresponding to the engine 11 and the HB controller 30B corresponding to the swing motor 21) that directly controls the other controlled units 40 and the HMI 50. The same applies to the notifications in steps S124 and S130 described later.

[0070] In step S112, other controlled units 40 have their operations restricted in response to the reception of an operation restriction notification (i.e., a control signal) from the excavator controller 30A. For example, the control valve 17 and various valves that adjust the pilot pressure acting on the control valve 17 may be operationally restricted so that the response and operating speed of the hydraulic actuator to the operation input to the operating device 26 become slower than normal. Also, for example, the inverter 18B may be operationally restricted so that the response and operating speed of the swing electric motor 21 to the operation input to the operating device 26 become slower than normal.

[0071] Also, in step S114, the HMI 50 notifies the operator in the cab 10 of the occurrence of an abnormality related to the motor generator 12 by a visual method (display), an auditory method (sound), etc. in response to the reception of an operation restriction notification (i.e., a control signal) from the excavator controller 30A. In other words, the HMI 50 notifies the operator of a warning (hereinafter, "operation restriction warning") indicating that the excavator but is in an operation-restricted and restricted operation state due to the occurrence of the abnormality.

[0072] Still, in step S114, the HMI 50 may further issue a warning (hereinafter, "operation suppression warning") to prompt suppression of operations through the excavator's operating device 26 (for example, to prompt a gentler operating speed). Thereby, in addition to the operation restriction of other controlled units 40, the operation itself for operating other controlled units 40 can be suppressed. Also, instead of the operation restriction of other controlled units 40, only the notification of the operation suppression warning to the operator may be performed. Thereby, instead of automatically imposing an operation restriction in the excavator's control system, the operator can be made to be somewhat more cautious about operating the operating device 26, achieving a similar effect.

[0073] After the electric generator 12 stops (step S108), at step S116, the HB controller 30B performs a process of attempting to restart the electric generator 12 (hereinafter, "restart process"). Specifically, the HB controller 30B restarts the inverter 18A and performs a process based on the self-diagnostic function regarding the electric generator 12 (hereinafter, "self-diagnostic process").

[0074] At step S118, the HB controller 30B determines whether the restart is successful, that is, whether it is confirmed that the abnormality regarding the electric generator 12 has been resolved through the self-diagnostic process accompanying the restart. In this example, the abnormality regarding the electric generator 12 has been resolved, and the HB controller 30B determines that the restart is successful.

[0075] In addition, when the abnormality regarding the electric generator 12 has not been resolved, the processes of step S108 and step S116 may be repeated until it is confirmed that the abnormality has been resolved, with a previously specified number of times as the upper limit.

[0076] At step S120, the HB controller 30B transmits a notification indicating that the restart of the electric generator 12 is successful, that is, a restart success notification, to the excavator controller 30A along with the normal recovery of the electric generator 12.

[0077] Then, at step S122, the HB controller 30B controls the inverter 18A to resume the normal operation of the electric generator 12, that is, to resume the servo control by the inverter 18A.

[0078] On the other hand, at step S124, in response to receiving the restart success notification from the HB controller 30B, the excavator controller 30A transmits a notification (hereinafter, "operation restriction release notification") to the other control target unit 40 and the HMI 50 to release the operation restriction of the other control target unit 40.

[0079] In step S126, in response to receiving an operation restriction release notice (i.e., a control signal) from the excavator controller 30A, the other controlled unit 40 releases the operation restriction and returns to normal operation.

[0080] Also, in step S128, in response to receiving the operation restriction release notice (i.e., the control signal), the HMI 50 cancels the warning that the notification to the operator is continuing. As a result, the HMI 50 can notify the operator that the operation restriction of the excavator has been released.

[0081] In contrast, as shown in FIG. 3 B, in this example, in step S118, the HB controller 30B determines that the restart has failed. Therefore, in step S130, the HB controller 30B transmits a notice indicating that the restart has failed (hereinafter, "restart failure notice") to the excavator controller 30A due to the failure of the restart of the motor generator 12, and in step S132, stops the motor generator 12 (i.e., the inverter 18A).

[0082] On the other hand, in step S134, in response to receiving the restart failure notice from the HB controller 30B, the excavator controller 30A transmits a notice (hereinafter, "operation stop notice") indicating that the other controlled unit 40 is to be stopped to the other controlled unit 40 and the HMI 50.

[0083] In step S136, in response to receiving the operation stop notice (i.e., the control signal) from the excavator controller 30A, the other controlled unit 40 stops. As a result, the engine 11, the electric drive system, etc. all stop, and the excavator stops.

[0084] Also, in step S138, in response to the operation stop notice from the excavator controller 30A, the HMI 50 notifies the operator in the cab 10 of a warning indicating that the excavator has stopped due to an abnormality related to the motor generator 12.

[0085] Thus, in this example, when an abnormality occurs in the motor generator 12, the control device 30 continues the operation of the excavator while restricting the operation of the excavator. Thereby, the excavator can continue to operate with the power of the engine 11 and the power of the power storage system 120 (capacitor 19), and it is possible to suppress a decrease in work efficiency when an abnormality occurs.

[0086] In addition, when an abnormality occurs in the engine 11, which is the other power source for the hydraulic drive system, the control device 30 may perform similar control. That is, when an abnormality occurs in the engine 11, the control device 30 may continue the operation of the excavator with the power of the motor generator 12 while restricting the operation of the excavator. Further, when an abnormality occurs in the capacitor 19 (power storage system 120), the control device 30 may perform similar control. That is, when an abnormality occurs in the capacitor 19, the control device 30 may continue the operation of the excavator in a mode where the swing motor 21 is driven with the power of the motor generator 12 while restricting the operation of the excavator, and the motor generator 12 is driven with the regenerative power of the swing motor 21.

[0087] Also, in this example, when an abnormality occurs in the motor generator 12, the control device 30 either restricts the operation of the excavator or issues a notification prompting suppression of an operation input to the excavator (that is, an operation input to the operation device 26), and continues the operation of the excavator. Thereby, the control device 30 can restrict the operation of the excavator in accordance with a decrease in the response and output of the main pump 14 and the swing motor 21 due to the abnormality in the motor generator 12, and realize continuous operation of the mobile crane.

[0088] Also, in this example, when an abnormality occurs in the motor generator 12, the control device 30 continues the operation of the excavator while restricting the operation of the excavator, attempts to recover from the abnormality, and releases the operation restriction when the recovery from the abnormality is successful. Thereby, the control device 30 can return the excavator from the restricted operation to the normal operation while ensuring safety and the like.

[0089] [Second Example of Working Machine (Mobile Crane)] Next, with reference to FIGS. 4 (FIGS. 4A and 4B) and 5, as a second example of the working machine according to the present embodiment, a mobile crane will be described.

[0090] [Overview of Mobile Crane] First, with reference to FIGS. 4A and 4B, the overview of the mobile crane will be described.

[0091] FIGS. 4A and 4B respectively show a front view and a side view of an example of the mobile crane according to the present embodiment.

[0092] As shown in FIGS. 4A and 4B, the mobile crane according to the present embodiment includes a gantry frame 140 composed of a plurality of columns 141A and a girder 141B supported by the plurality of columns 141A, and wheels 142 attached to the lower ends of the gantry frame 140 (columns 141A). The mobile crane can move along the rail 143 using the wheels 142.

[0093] Also, the mobile crane according to the present embodiment includes a trolley 145 mounted on the girder 141, and a hoisting machine 146 is mounted on the trolley 145.

[0094] The hoisting machine 146 winds up and winds down a hoisting work part 147 including a wire 147A and a hook 147B attached to the tip of the wire 147A by the power of a hoisting motor 153 described later. and attached case to

[0095] [Configuration of Mobile Crane] Next, in addition to FIGS. 4A and 4B, with reference to FIG. 5, the configuration of the mobile crane will be described.

[0096] The electric drive system of the mobile crane according to this embodiment includes an AC power supply 160, a rectifier 163, a power conversion device 165, a power storage system 190 composed of a power storage device 167 and a power conversion device 168, etc., and a DC bus 170. Further, the electric drive system of the mobile crane according to this embodiment includes a traveling motor 151, a traversing motor 152, a hoisting motor 153, inverters 154 to 156, and power conversion devices 157 to 159. The components related to the electric drive system of the mobile crane are respectively mounted on the gantry frame 140.

[0097] The AC power supply 160 is connected to the DC bus 170 via the rectifier 163 and the power conversion device 165, and the power storage device 167 is connected to the DC bus 170 via the power conversion device 168. Also, the traveling motor 151, the traversing motor 152, and the hoisting motor 153 are connected to the DC bus 170 via the inverter 154 and the power conversion device 157, the inverter 155 and the power conversion device 158, and the inverter 156 and the power conversion device 159.

[0098] The AC power supply 160 includes an engine 161 and a generator 162 (an example of a power source) driven by the engine 161.

[0099] The rectifier 163 rectifies the generated power (AC) output from the AC power supply 160 and outputs DC power to the power conversion device 165.

[0100] Under the control of the controller 180, the power conversion device 165 converts the generated power (DC) of the AC power supply 160 supplied via the rectifier 163 to a predetermined target voltage and outputs it to the DC bus 170.

[0101] The power storage device 167 (an example of a power source) is connected to the DC bus 70 via the power conversion device 168, supplies DC power to the DC bus 170, or charges the DC power supplied from the DC bus 170 (the regenerative power of the hoisting motor 153 or the generated power of the AC power supply 160). The power storage device 167 is, for example, a lithium-ion battery module.

[0102] The power conversion device 168 boosts the DC power of the power storage device 167 and discharges it to the DC bus 170, or steps down the DC power of the DC bus 170 and charges the power storage device 167 under the control of the controller 180.

[0103] The DC bus 170 includes a positive-side bus 170P and a negative-side bus 170N, and a smoothing capacitor 172 is provided between the positive-side bus 170P and the negative-side bus 170N.

[0104] The traveling motor 151 (an example of an actuator and an electric actuator) drives the wheels 142 and causes the mobile crane to travel in the front-rear direction.

[0105] The traversing motor 152 (an example of an actuator and an electric actuator) is mounted on the trolley 145 and moves the trolley 145, that is, the hoisting machine 146 and the lifting work unit 147, in the traversing direction (i.e., the left-right direction) along the girder 141B.

[0106] The hoisting motor 153 (an example of an actuator and an electric actuator) winds up and winds down the lifting work unit 147 (wire 147A).

[0107] The inverters 154 to 156 drive the traveling motor 151, the traversing motor 152, and the hoisting motor 153 under the control of the controller 180, respectively. Specifically, the inverters 154 to 156 convert the DC power supplied via the power conversion devices 157 to 159 into AC power and output it to the traveling motor 151, the traversing motor 152, and the hoisting motor 153, respectively. Further, when the hoisting motor 153 is winding down, the inverter 156 converts the regenerative power (AC) generated by the hoisting motor 153 into DC power and outputs it to the DC bus 170 via the power conversion device 159.

[0108] Power converters 157 to 159 boost the voltage of DC bus 170 under the control of controller 180, and output the boosted DC power to inverters 154 to 156 respectively. Further, power converter 159 steps down the regenerative power (DC) supplied from hoisting motor 153 via inverter 156 under the control of controller 180 during the lowering operation of hoisting motor 153, and outputs it to DC bus 170.

[0109] The control system of the mobile crane according to this embodiment includes controller 180.

[0110] Controller 180 (an example of a control device), as described above, controls inverters 154 to 156, power converters 157 to 159, power converter 165, and power converter 168 to control the operations of traveling motor 151, traversing motor 152, and hoisting motor 153, or to control the charging and discharging of power storage device 167.

[0111] In addition, controller 180 has a self-diagnosis function related to the electric drive system, and detects various abnormalities in the electric drive system.

[0112] Specifically, controller 180 may detect an abnormality related to AC power source 160, that is, an abnormality related to generator 162. For example, controller 180 may detect a temperature abnormality, a current abnormality (e.g., overcurrent), a voltage abnormality (e.g., overvoltage), etc. by monitoring the temperature, current, and voltage of generator 162. Further, controller 180 may detect an abnormality of engine 161 that drives generator 162 (e.g., an abnormality of various actuators such as a fuel injection device, an abnormality of various sensors such as a crank angle sensor, an abnormality of the exhaust system, etc.), or an abnormality of rectifier 163 or power converter 165 (e.g., a temperature abnormality, a current abnormality, a voltage abnormality, etc., and an abnormality of components such as semiconductor switches, resistors, capacitors, diodes, etc.).

[0113] In addition, the controller 180 may detect an abnormality in the power storage system 190, that is, an abnormality related to the power storage device 167. For example, the controller 180 may detect an internal resistance abnormality, a degradation abnormality, a temperature abnormality, a current abnormality, a voltage abnormality, etc. by monitoring the temperature, current, and voltage of the power storage device 167. Further, the controller 180 may detect an abnormality in the power conversion device 168 (for example, a temperature abnormality, a current abnormality, a voltage abnormality, etc., or an abnormality in components such as semiconductor switches, resistors, capacitors, diodes, etc.).

[0114] <Operation of the mobile crane when an abnormality occurs> Next, the operation of the mobile crane when an abnormality occurs will be described.

[0115] Similar to the case of the excavator described above, when the controller 180 detects an abnormality in either the generator 162 or the power storage device 167 as a plurality of power sources, the controller 180 may continue to operate the own machine (mobile crane) with the other power while restricting the operation of the own machine. Thereby, the mobile crane can continue to operate with the other power different from the power source corresponding to the abnormality, and suppress a decrease in work efficiency when an abnormality occurs.

[0116] Also, similar to the case of the excavator described above, when an abnormality occurs in either the generator 162 or the power storage device 167, the controller 180 either restricts the operation of the mobile crane or gives a notice to prompt suppression of the operation input related to the mobile crane (that is, the operation input related to the traveling motor 151, the traversing motor 152, and the hoisting motor 153), and continues the operation of the mobile crane. Thereby, the controller 180 restricts the operation of the mobile crane in accordance with a decrease in the response or output of the traveling motor 151, the traversing motor 152, and the hoisting motor 153 due to an abnormality in either the generator 162 or the power storage device 167, and can realize the continuous operation of the mobile crane.

[0117] In addition, when an abnormality occurs in either the generator 162 or the power storage device 167, the controller 180 may continue to operate the mobile crane while restricting the operation of the mobile crane, attempt to recover from the abnormality, and release the operation restriction when the recovery from the abnormality is successful. Thereby, the controller 180 can return the mobile crane from the restricted operation to the normal operation while ensuring safety and the like.

[0118] [Operation of the present embodiment] Next, the operation of the work machine according to the present embodiment will be described.

[0119] When a predetermined abnormality occurs, the work machine according to the present embodiment performs at least one of notifying the operator to suppress the operation of the own machine and automatically shifting to a state in which the operation of the own machine in response to the operation input is restricted, and continues the operation of the own machine.

[0120] Thereby, even when a predetermined abnormality occurs, the work machine can continue the operation of the work machine while ensuring safety and the like by restricting the operation or prompting the operator to suppress the operation. Therefore, compared with the case where the work machine is stopped in response to the occurrence of an abnormality, it is possible to suppress a decrease in the work efficiency of the work machine.

[0121] In addition, the work machine not only prompts the operator to suppress the operation of the own machine or automatically shifts to a state in which the operation of the own machine in response to the operation input is restricted, or the like but also may, through the HMI 50 or the like, interrupt the work (that is, interrupt the operation of the operation device 26) and notify the operator to retreat the own machine to a relatively safe place or a place where it does not interfere with other work machines. Thereby, the safety of the work machine and the work site where the work machine performs the work can be further improved.

[0122] In addition, when a predetermined abnormality occurs, the work machine according to the present embodiment continues the operation while restricting the operation, and then releases the operation restriction.

[0123] As a result, even when a predetermined abnormality occurs, the working machine can limit its operation, ensure safety, etc., continue operation, and finally release the operation limit and return to normal operation. Therefore, compared with the case where the working machine is stopped when an abnormality occurs, it is possible to suppress a decrease in the working efficiency of the working machine.

[0124] In addition, the working machine according to the present embodiment may attempt to recover from the predetermined abnormality when the predetermined abnormality occurs, and release the operation limit when the recovery from the predetermined abnormality is successful.

[0125] As a result, the working machine according to the present embodiment can return from the restricted operation to the normal operation while ensuring safety, etc.

[0126] Note that the working machine may attempt to recover from a predetermined abnormality while continuing normal operation as long as safety, etc. are ensured when the predetermined abnormality occurs. Specifically, the working machine may continue normal operation without restricting the operation of components other than the component in which the abnormality has occurred (for example, other controlled units 40). In addition, when a predetermined abnormality occurs, the working machine may continue normal operation and then gradually limit its operation according to the situation of its own machine. Specifically, the working machine may continue normal operation for components other than the component in which the abnormality has occurred, and gradually limit the operation according to the situation of the other component or related components of the other component. For example, when an abnormality related to the motor generator 12 occurs in the working machine (excavator), when the remaining capacity of the capacitor 19 is equal to or greater than a predetermined threshold value, the normal operation of the swing motor 21 may be continued, and when the remaining capacity of the capacitor 19 is less than the predetermined threshold value, the operation of the swing motor 21 may be restricted. Further, the swing motor 21 may be configured to increase the degree of operation restriction in accordance with a decrease in the remaining capacity of the capacitor 19 under the control of the inverter 18B. Thereby, the working machine is abnormal regarding the motor generator 12 and restorationDuring the period until it returns, it is possible to suppress a situation where the remaining capacity of the capacitor 19 becomes zero and the turning operation of the upper swing body 3 cannot be continued.

[0127] Moreover, the working machine according to the present embodiment includes a plurality of power sources for actuators that operate the own machine. And, when an abnormality occurs in some of the plurality of power sources as a predetermined abnormality, the working machine according to the present embodiment may continue operation by the remaining power sources among the plurality of power sources.

[0128] Thereby, even when an abnormality occurs in some of the plurality of power sources, the working machine can continue operation with power from the remaining power sources while restricting its operation.

[0129] Furthermore, the working machine according to the present embodiment includes a hydraulic pump that supplies hydraulic oil to a hydraulic actuator, and as a plurality of power sources, an engine and an electric motor that drive the hydraulic pump. And, when an abnormality regarding either the engine or the electric motor occurs as a predetermined abnormality, the working machine according to the present embodiment may continue operation of the own machine by the other power.

[0130] Thereby, when the working machine can drive the hydraulic actuator via the hydraulic pump with the power of both the engine and the electric motor, even when an abnormality regarding either the engine or the electric motor occurs, it can drive the hydraulic pump with the other power and continue operation of the own machine.

[0131] Moreover, the working machine according to the present embodiment includes a generator and a power storage device that supply electric power to an electric actuator as a plurality of power sources. And, when an abnormality regarding either the generator or the power storage device occurs as a predetermined abnormality, the working machine of the present embodiment continues operation of the own machine by the other power.

[0132] Accordingly, when the machine tool can drive the electric actuator with the power (electric power) of both the generator and the power storage device, even if an abnormality occurs in either the generator or the power storage device, the electric actuator can be driven with the power (electric power) of the other, and the operation of the machine tool itself can be continued.

[0133] As described above, the embodiments for carrying out the present invention have been described in detail. However, the present invention is not limited to such specific embodiments, and various modifications and changes are possible within the scope of the gist of the present invention described in the claims.

[0134] For example, in the above-described embodiment, instead of being operated by the operator in the cabin 10, the machine tool may be remotely operated from outside the machine tool. For example, the machine tool may have a communication device capable of communicating with a predetermined external device, and an operation signal regarding remote operation may be received from the external device through the communication device, and the control valve 17 and the inverters 18A and 18B may be controlled according to the operation signal. In this case, the notification content (various warnings) of the HMI 50 in the above-described embodiment may be in a form that can be confirmed by the operator performing the remote operation through an HMI (for example, a display or the like) installed in the external device.

[0135] Further, in the above-described embodiment and the modification, the machine tool may perform a predetermined operation autonomously without relying on the operation by the operator in the cabin 10 or the remote operation based on the operation information from the external device. In this case, for example, when a predetermined abnormality occurs, the machine tool autonomously continues the predetermined operation while restricting the operation.

Explanation of Reference Numerals

[0136] 1A, 1B Travel hydraulic motor (actuator, hydraulic actuator) 7 Boom cylinder (actuator, hydraulic actuator) 8 Arm cylinder (actuator, hydraulic actuator) 9 Bucket cylinder (actuator, hydraulic actuator) 11 Engine 12 Motor Generator (Motor) 14 Main Pump (Hydraulic Pump) 30 Control Device 30A Excavator Controller 30B Hybrid Controller 30C Engine Controller 151 Travel Motor (Actuator, Electric Actuator) 152 Swing Motor (Actuator, Electric Actuator) 153 Hoist Motor (Actuator, Electric Actuator) 162 Generator 167 Energy Storage Device 180 Controller (Control Device)

Claims

**Claim 1**: A working machine comprising a control device, wherein when a predetermined abnormality occurs, the control device automatically shifts to a state in which it restricts the operation of the working machine with respect to an operation input while continuing the operation of the working machine, attempts to recover from the predetermined abnormality, and as a result of the attempt, if the recovery from the predetermined abnormality is successful, releases the operation restriction of the working machine, and if the recovery from the predetermined abnormality fails, stops the operation of the working machine. A working machine. **Claim 2**: A working machine comprising a control device, wherein when a predetermined abnormality occurs, the control device attempts to recover from the predetermined abnormality while continuing the operation while restricting the operation of the working machine, and thereafter, if the recovery from the predetermined abnormality is successful, releases the operation restriction of the working machine, and if the recovery from the predetermined abnormality fails, stops the operation of the working machine. A working machine. **Claim 3**: The control device, when the predetermined abnormality occurs, gives a notice to prompt the operator to interrupt the work of the working machine and evacuate to a relatively safe place or a place where it does not interfere with other working machines in the vicinity. The working machine according to claim 1. **Claim 4**: An actuator for operating a working machine and a plurality of power sources for the actuator, wherein when an abnormality occurs in some of the plurality of power sources as the predetermined abnormality, the control device continues the operation of the working machine by the remaining power sources among the plurality of power sources. The working machine according to any one of claims 1 to 3. **Claim 5** comprises a hydraulic pump for supplying hydraulic oil to a hydraulic actuator as the actuator, the plurality of power sources include an engine and an electric motor, the hydraulic pump is driven by the engine and the electric motor, wherein when an abnormality related to either the engine or the electric motor occurs as the predetermined abnormality, the control device continues the operation of the working machine by the other power. The working machine according to claim 4. **Claim 6** the plurality of power sources include a generator and a power storage device for supplying power to an electric actuator as the actuator, wherein when an abnormality related to either the generator or the power storage device occurs as the predetermined abnormality, the control device continues the operation of the working machine by the other power. The working machine according to claim 4. **Claim 7**: A working machine comprising a control device, When a predetermined abnormality occurs, the control device continues the normal operation of the working machine and attempts to recover from the predetermined abnormality. If the attempt fails to recover from the predetermined abnormality as a result, the control device stops the operation of the working machine. Working machine. According to claim 8, when the predetermined abnormality occurs, the control device continues the normal operation of the working machine, and then, depending on the state of the working machine, attempts to recover from the predetermined abnormality while gradually restricting the operation of the working machine. If the attempt is successful in recovering from the predetermined abnormality as a result, the control device releases the operation restriction of the working machine. If the attempt fails to recover from the predetermined abnormality, the control device stops the operation of the working machine. The working machine according to claim 7.

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