System and method for controlling industrial machinery

Abstract

Maintaining minimum functionality so that broken-down machinery can be moved to the repair site. [Solution] The system is a system for controlling a work machine, comprising: an actuator for driving the work machine; a control valve for operating the actuator; a controller for controlling the control valve based on a signal from an electrical operating unit; a redundant operating system separate from the controller; and a redundant operating system switching unit for enabling the operation of the actuator by the redundant operating system.

Description

Technical Field

[0001] The present disclosure relates to a system and a method for controlling a work machine.

Background Art

[0002] As a system for operating a vehicle, there is a technology for controlling an electronic valve and a pump by a signal of an electric lever via a controller. For example, Patent Document 1 discloses that when driving a construction machine or moving a work machine equipped thereon by hydraulic drive, an operation valve and a variable pump in a hydraulic piping system are used as a hydraulic control valve and a pump that are operated via a controller operated by an electric lever.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above system, when a main electronic component (for example, a controller, an electric lever sensor, electric wiring, etc.) fails, it is required to maintain a minimum function (limp home function) that enables the work machine to be moved to a repair location.

[0005] An aspect of the present disclosure aims to maintain a minimum function so that a failed work machine can be moved to a repair location.

Means for Solving the Problems

[0006] A system according to one aspect of the present disclosure is a system for controlling a work machine, comprising: an actuator for driving the work machine; a control valve for operating the actuator; a controller for controlling the control valve based on a signal from an electrical operating unit; a redundant operating system separate from the controller; and a redundant operating system switching unit for enabling the operation of the actuator by the redundant operating system. [Effects of the Invention]

[0007] According to the aspects of this disclosure, it is possible to maintain a minimum level of functionality so that a broken-down work machine can be moved to a repair location. [Brief explanation of the drawing]

[0008] [Figure 1] This is a perspective view showing a work machine according to the first embodiment. [Figure 2] This is a schematic diagram showing the configuration of the operator's cab of the work machine according to the first embodiment. [Figure 3] This is a diagram showing an example of a system according to the first embodiment. [Figure 4] This figure shows an example of a redundant circuit for limp home according to the first embodiment. [Figure 5] This figure shows an example of a hydraulic circuit according to the first embodiment. [Figure 6] This figure shows an example of the control flow of the system according to the first embodiment. [Figure 7] This figure shows an example of the control flow, following Figure 6. [Figure 8] This figure illustrates an example of the control of a work machine according to the first embodiment. [Figure 9] This figure, following Figure 8, illustrates an example of machine control. [Figure 10] This figure shows an example of a signal from the electrical control unit according to the first embodiment. [Figure 11] This figure shows an example of how the redundant operation system switching unit according to the first embodiment is used to notify the operator that the system has been successfully switched over. [Figure 12] It is a diagram for explaining an example of control of a working machine according to the second embodiment. [Figure 13] It is a diagram for explaining an example of control of a working machine following FIG. 12. [Figure 14] It is a diagram for explaining an example of control of a working machine according to the third embodiment. [Figure 15] It is a diagram for explaining an example of control of a working machine following FIG. 14. [Figure 16] It is a diagram for explaining an example of control of a working machine according to the fourth embodiment. [Figure 17] It is a diagram showing an example of setting of an operation pattern according to the fourth embodiment. [Figure 18] It is a diagram for explaining an example of control of a working machine according to the fifth embodiment.

MODE FOR CARRYING OUT THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In this embodiment, as a system, an example of a system for controlling a working machine will be described.

[0010] In the following description, expressions indicating relative or absolute arrangements such as "parallel", "orthogonal", "center", "coaxial", etc. not only strictly mean such arrangements or states, but also include arrangements or states that are relatively displaced with tolerances and angles or distances that can obtain the same function. In the drawings used in the following description, in order to make each member recognizable in size, the scale of each member may be appropriately changed and shown.

[0011] [[ID=**35**]]<Working machine> FIG. 1 is a perspective view showing a working machine 1 according to the first embodiment. In the embodiment, the working machine 1 is a hydraulic excavator. As shown in FIG. 1, the working machine 1 includes a traveling body 2, a revolving body 3, and a working device 4. The working machine 1 excavates and levels earth and sand at a work site or the like. The traveling body 2 and the revolving body 3 constitute the vehicle body of the working machine 1.

[0012] The traveling body 2 supports the working machine 1 so that it can travel. The traveling body 2 includes a pair of left and right crawler belts 5L and 5R. The left and right crawler belts 5L and 5R are driven by traveling motors 10L and 10R. The working machine 1 moves forward, turns, or moves backward by the rotation of the left and right crawler belts 5L and 5R.

[0013] The revolving body 3 is supported by the traveling body 2 so that it can revolve. The revolving body 3 performs a revolving operation with respect to the traveling body 2 by a revolving motor 11. The revolving body 3 supports the working machine 4, the cab 6, and the machine room 7.

[0014] The working machine 4 is supported by the vehicle body of the working machine 1 so that it can operate. The working machine 4 is driven by hydraulic pressure. The working machine 4 includes a boom 21, an arm 22, and an attachment 23. The attachment 23 is an example of a working tool. The attachment 23 in the example shown in FIG. 1 is a bucket. The base end portion of the boom 21 is rotatably attached to the revolving body 3. The base end portion of the arm 22 is rotatably attached to the tip end portion of the boom 21. The attachment 23 is rotatably attached to the tip end portion of the arm 22.

[0015] The working machine 1 includes a plurality of actuators 12, 13, and 14 for driving the working machine 4. The plurality of actuators 12, 13, and 14 for driving the working machine 4 includes a boom cylinder 12, an arm cylinder 13, and an attachment cylinder 14.

[0016] The boom cylinder 12 is a hydraulic cylinder for driving the boom 21. The base end portion of the boom cylinder 12 is attached to the revolving body 3. The tip end portion of the boom cylinder 12 is attached to the boom 21. The arm cylinder 13 is a hydraulic cylinder for driving the arm 22. The base end portion of the arm cylinder 13 is attached to the boom 21. The tip end portion of the arm cylinder 13 is attached to the arm 22. The attachment cylinder 14 is a hydraulic cylinder for driving the attachment 23. The base end of the attachment cylinder 14 is attached to the arm 22. The tip end of the attachment cylinder 14 is attached to the attachment 23.

[0017] The operator's cab 6 is where the operator of the work machine 1 sits and operates and controls it. The operator's cab 6 is located, for example, on the left side of the front end of the slewing body 3. The operator's cab 6 of the work machine 1 is equipped with an operating device 40 for operating the work machine 1. The operating device 40 is operated by the operator to operate the work machine 1. The operating device 40 is configured to output an operating signal in response to the operator's operation.

[0018] The machine room 7 is located, for example, behind the driver's cab 6 (at the rear end side of the slewing body 3). A controller 30, a main valve module 31, etc., are provided between the driver's cab 6 and the machine room 7. The machine room 7 is equipped with an engine 32, pumps 33, 34, etc.

[0019] <Driver's cab configuration> Figure 2 is a schematic diagram showing the configuration of the operator's cab 6 of the work machine 1 according to the first embodiment. As shown in Figure 2, the driver's cab 6 is equipped with an operating device 40 and a driver's seat 41. The operating device 40 includes a left operating lever 42L, a right operating lever 42R, a left travel lever / pedal 43L, and a right travel lever / pedal 43R. In the following description, the left operating lever 42L, the right operating lever 42R, the left travel lever / pedal 43L, and the right travel lever / pedal 43R will be referred to as the "electrical operating unit" as appropriate.

[0020] The left operating lever 42L is configured to control the rotational movement of the slewing body 3 and the digging / dumping movement of the arm 22. The right operating lever 42R is configured to control the digging / dumping movement of the attachment 23 and the raising / lowering movement of the boom 21.

[0021] The left travel lever / pedal 43L and the right travel lever / pedal 43R are configured to control the movement of the work machine 1. The left travel lever / pedal 43L is configured to control the rotation of the left track 5L of the vehicle 2. The right travel lever / pedal 43R is configured to control the rotation of the right track 5R of the vehicle 2. Note that the left travel lever / pedal 43L and the right travel lever / pedal 43R may each be configured with separate electrical control units for the lever and pedal.

[0022] The driver's cab 6 is equipped with a display device 45, which is, for example, a monitor with an operating device. The display device 45 is positioned, for example, to the right of the right travel lever / pedal 43R and in front of the right operating lever 42R.

[0023] The driver's cab 6 is equipped with a throttle dial 46 and switches 47 that allow for adjustment of the engine speed. The throttle dial 46 and switches 47 are located, for example, to the right of the driver's seat 41 and behind the right-hand control lever 42R.

[0024] <System> Figure 3 shows an example of system 100 according to the first embodiment. Figure 4 shows an example of a redundant circuit for limp home according to the first embodiment. Figure 5 shows an example of a hydraulic circuit according to the first embodiment. Referring to Figures 3 to 5, the system 100 of this embodiment operates the work machine 1, which includes an actuator 10 that drives the traveling body 2, the rotating body 3, and the work machine 4, by controlling the control valve 50 via a signal from the operating device 40 through the controller 30.

[0025] System 100 includes a plurality of actuators 10L, 10R, 11, 12, 13, and 14 for driving the vehicle 2, the slewing body 3, and the work implement 4. System 100 includes left and right travel motors 10L and 10R as actuators 10L and 10R for driving the vehicle 2. The left and right travel motors 10L and 10R can move the vehicle 2 forward and backward, and move the left and right tracks 5L and 5R of the vehicle 2 in different directions. System 100 includes a slewing motor 11 as actuator 11 for driving the slewing body 3. The slewing motor 11 can slewing the slewing body 3 relative to the vehicle 2. System 100 includes a boom cylinder 12, an arm cylinder 13, and an attachment cylinder 14 as actuators 12, 13, and 14 for driving the work implement 4.

[0026] System 100 includes a plurality of electrical operating units 42L, 42R, 43L, and 43R as an operating device 40. The plurality of electrical operating units 42L, 42R, 43L, and 43R are, for example, levers or pedals. The operating device 40 includes a left operating lever 42L, a right operating lever 42R, a left travel lever / pedal 43L, and a right travel lever / pedal 43R (see Figure 2).

[0027] The system 100 includes control valves 50, which consist of left and right travel control valves 50L and 50R for controlling the left and right travel motors 10L and 10R respectively, a slewing control valve 51 for controlling the slewing motor 11, a boom control valve 52 for controlling the boom cylinder 12, an arm control valve 53 for controlling the arm cylinder 13, and an attachment control valve 54 for controlling the attachment cylinder 14. Each valve 50L, 50R, 51, 52, 53, and 54 has a spool. The displacement of the spool is limited by the pilot pressure generated by the EPC valve, and as a result, the opening area is controlled.

[0028] The system 100 includes an EPC (Electromagnetic Proportional Control) valve 60 for controlling the working fluid flowing to the control valve 50 based on a predetermined control signal from the controller 30. Multiple EPC valves 60 are provided, corresponding to the control valves 50L, 50R, 51, 52, 53, and 54 (multiple control valves). Based on the control signal from the controller 30, the EPC valves 60 generate pilot pressure to control the spool stroke of the corresponding control valve. In other words, the controller 30 can control the control valves 50 by controlling the pilot pressure generated by the EPC valves 60. The EPC valve 60 includes left and right travel EPC valves 60LF, 60LR, 60RF, and 60RR for controlling the spool strokes of the left and right travel control valves 50L and 50R respectively, slewing EPC valves 61L and 61R for controlling the spool stroke of the slewing control valve 51, boom EPC valves 62U and 62D for controlling the spool stroke of the boom control valve 52, arm EPC valves 63U and 63D for controlling the spool stroke of the arm control valve 53, and attachment EPC valves 64U and 64D for controlling the spool stroke of the attachment control valve 54.

[0029] The system 100 includes a controller 35 (engine controller 35) for controlling the engine 32, separate from the controller 30. The engine controller 35 may be configured to start the engine 32, for example, by receiving a signal from the controller 30 that permits the engine 32 to start.

[0030] System 100 includes redundant operating systems 70L, 70R, 71, 72, 73, and 74 separate from the controller 30, and a redundant operating system switching unit 75 for enabling the operation of actuators 10L, 10R, 11, 12, 13, and 14 by the redundant operating systems 70L, 70R, 71, 72, 73, and 74.

[0031] System 100 includes redundant operation systems 70L, 70R, 71, 72, 73, and 74, which include left and right travel redundant operation switches 70L and 70R for redundantly operating the left and right travel motors 10L and 10R, a slewing redundant operation switch 71 for redundantly operating the slewing motor 11, a boom redundant operation switch 72 for redundantly operating the boom cylinder 12, an arm redundant operation switch 73 for redundantly operating the arm cylinder 13, and an attachment redundant operation switch 74 for redundantly operating the attachment cylinder 14.

[0032] In Figure 4, the redundant control system switching unit 75 is shown as the redundant control system enable switch. The redundant control system switching unit 75 has a common terminal 75a, an off terminal 75b, and an on terminal 75c. The common terminal 75a of the redundant control system switching unit 75 is electrically connected to an external power supply (not shown) mounted on the work machine 1. The external power supply mounted on the work machine 1 is, for example, a battery that outputs a voltage of 24V. The off terminal 75b of the redundant control system switching unit 75 is electrically connected to the controller 30 by an electrical connection line. The on terminal 75c of the redundant control system switching unit 75 is electrically connected to the input terminal of the register 76. The on terminal 75c of the redundant control system switching unit 75 is electrically connected to the controller 30 by an electrical connection line. When the redundant control system switching unit 75 is turned off, the common terminal 75a and the off terminal 75b become conductive, and the voltage from the external power supply mounted on the work machine 1 is input to the controller 30. When the redundant operation system switching unit 75 is turned ON, the common terminal 75a and the ON terminal 75c become conductive, and the voltage from the external power supply mounted on the work machine 1 is input to the controller 30 and the register 76. The output terminal of the register 76 is electrically connected to each redundant operation switch via an electrical connection line.

[0033] The system 100 can enable or disable the operation of actuators 10L, 10R, 11, 12, 13, and 14 by redundant operation systems 70L, 70R, 71, 72, 73, and 74 using the redundant operation system switching unit 75. For example, when the redundant operation system enable switch is turned ON by the operator, each actuator becomes capable of operation by its respective redundant operation switch. On the other hand, when the redundant operation system enable switch is turned OFF by the operator, each actuator becomes capable of operation by its respective redundant operation switch.

[0034] In Figure 5, the system 100 includes a main pump 33, a pilot pump 34, tanks 81-85, and a bleed valve 86. The main pump 33 pumps hydraulic oil as the working fluid. The main pump 33 pumps the working fluid to the control valve 50. The pilot pump 34 supplies pilot pressure to the EPC valve 60.

[0035] System 100 includes multiple tanks 81-85. Each of the multiple tanks 81-85 corresponds to the main pump 33, pilot pump 34, EPC valves 60LF, 60LR, 60RF, 60RR, 61L, 61R, 62U, 62D, 63U, 63D, 64U, 64D, control valves 50L, 50R, 51, 52, 53, 54, and bleed valve 86.

[0036] System 100 includes an actuator load pressure sensor 88 that detects the circuit pressure between the control valve and the actuator, and a pump pressure sensor 89 that detects the circuit pressure between the main pump 33 and each control valve. The actuator load pressure sensor 88 is provided in both the inlet and outlet circuits of each actuator. The pressures detected by the actuator load pressure sensor 88 and the pump pressure sensor 89 are output to the controller 30.

[0037] The bleed valve 86 is installed between the circuit between the main pump 33 and the control valves 50L, 50R, 51, 52, 53, and 54 and the tank 85. The bleed valve 86 releases a portion of the working fluid pumped by the main pump 33 into the tank 85.

[0038] The system 100 includes a PPC (Proportional Pressure Control) lock setting unit 90 and a PPC main pressure lock solenoid valve 91. In Figure 4, the PPC lock setting unit 90 is shown as a PPC lock switch. The PPC lock setting unit 90 is operated by an operator to set the supply or shutoff of working fluid from the pilot pump 34 to the multiple EPC valves 60. The PPC main pressure lock solenoid valve 91 has, for example, a solenoid. When voltage is applied to the solenoid, the PPC main pressure lock solenoid valve 91 supplies working fluid discharged from the pilot pump 34 to the multiple EPC valves 60. When no voltage is applied to the solenoid, the PPC main pressure lock solenoid valve 91 shuts off the working fluid discharged from the pilot pump 34 and does not supply it to the multiple EPC valves 60.

[0039] The system 100 further includes a PPC lock release unit 92 that enables the lock of the PPC source pressure lock solenoid valve 91 to be released even if the PPC lock setting unit 90 is determined to be malfunctioning. In Figure 4, the PPC lock release unit 92 is shown as a PPC automatic lock release switch.

[0040] <Control Flow> Figure 6 shows an example of the control flow of system 100 according to the first embodiment. Figure 7 shows an example of the control flow following Figure 6. Referring to Figures 6 and 7, the controller 30 detects electrical signals from the electrical operating units 42L, 42R, 43L, and 43R. These electrical signals are, for example, proportional to the lever operation amount. Based on the detected electrical signals (lever operation amount), the controller 30 calculates the target flow rate for each axis. The controller 30 calculates the target flow rate for each axis for each corresponding actuator operation amount (in Figure 7, for each actuator operation amount from A to C).

[0041] The controller 30 calculates the target flow rate for the valve main circuit based on the calculation results of the target flow rates for each axis. The controller 30 then calculates the target flow rate for the pump based on the calculation results of the target flow rates for the valve main circuit.

[0042] The target pump flow rate Q_p is expressed by the following equation (1). In equation (1), Q_valve is the target flow rate of the valve main circuit, and Q_p_min is the minimum pump flow rate.

[0043]

number

[0044] The controller 30 calculates the pump capacity command value based on the calculation result of the target pump flow rate. Based on the calculation result of the pump capacity command value, the controller 30 performs a table conversion and determines the command current for the pump capacity.

[0045] The controller 30 calculates the target bleed opening area based on the calculation results of the target flow rate of the valve main circuit and the target flow rate of the pump.

[0046] The target bleed opening area A_bleed is expressed by the following equation (2). In equation (2), P_tgt represents the target pressure of the pump circuit.

[0047]

number

[0048] The controller 30 calculates the bleed valve command value based on the calculation result of the target bleed opening area. Based on the calculation result of the bleed valve command value, the controller 30 performs a table conversion and determines the bleed valve command current.

[0049] The controller 30 calculates the target valve opening area based on the calculation results of the target flow rate for each axis, the actuator load pressure, and the pump circuit pressure.

[0050] The target valve opening area A_tgt is expressed by the following equation (3). In equation (3), Q_tgt is the target flow rate for each axis, P_p is the pump circuit pressure, and P_act is the actuator load pressure.

[0051]

number

[0052] The controller 30 calculates the spool stroke command value based on the calculation result of the target valve opening area. Based on the calculation result of the spool stroke command value, the controller 30 performs a table conversion and determines the command current for the spool stroke.

[0053] <Control of working machinery> Figure 8 illustrates an example of the control of the work machine 1 according to the first embodiment. Figure 9 illustrates another example of the control of the work machine 1, following Figure 8. Referring to Figures 8 and 9, when the redundant operation system switching unit 75 is effectively switched, the controller 30 prevents the actuators (the slewing motor 11 and boom cylinder 12 in the example of Figure 9) from being operated in response to signals from the electrical operation units used under normal circumstances (electric levers 1 and 2 in the example of Figure 8).

[0054] The redundant operation system switching unit 75 is switched to an effective state, for example, when an operator turns on the redundant operation system enable switch. As shown in Figure 8, the state in which the redundant operation system enable switch is turned on means that the common terminal 75a and the ON terminal 75c are electrically connected. Under normal conditions, i.e., when the redundant operation system enable switch is in the off state, the controller 30 outputs a control signal to the EPC valve to generate pilot pressure for controlling the spool stroke of each control valve in response to an electrical signal from the electrical operation unit. When the redundant control system enable switch is ON, the controller 30 does not output a control signal to the EPC valve (the output of A1 shown in Figure 8 is set to zero). This prevents the actuator from being operated in response to electrical signals from the electrical control unit (for example, raising or lowering the boom, or swiveling left or right).

[0055] When the redundant operating system switching unit 75 is switched on, the controller 30 sets the capacity of the pump 33 that pumps the working fluid to a preset fixed capacity. For example, the capacity of the pump 33 may be changed by the swash plate. For example, the pump swash plate may be controlled by an output signal from the controller 30 (e.g., an output of 0 to 1A) (A2 shown in Figure 9). When controlling such a pump, when the redundant operating system enable switch is turned on, the controller 30 fixes the pump capacity command current (fixing the output of A2 shown in Figure 8 to a constant value). Note that if the controller 30 itself fails, the output will be zero (output 0A), so the capacity of the pump 33 will be fixed at the minimum.

[0056] The fixed capacity is set to a capacity that allows the actuator to operate at the minimum required speed. For example, the controller 30 is set to a fixed capacity that is sufficient to move the work machine at the minimum required speed.

[0057] When the redundant operation system switching unit 75 is switched on, the controller 30 sets the opening area of ​​the bleed valve 86 so that working fluid can be supplied from the pump 33 at a pressure that enables the actuator to operate. For example, when the redundant operation system enable switch is turned on, the controller 30 fixes the bleed valve 86 to a predetermined opening area so that pressure is secured that allows for travel, slewing, and boom raising / lowering (fixing the output of A3 shown in Figure 8 to a constant value). For example, the controller 30 sets the output (control signal) to the bleed valve 86 so that working fluid can be supplied from the main pump 33 to the control valves (slewing control valve 51 and boom control valve 52 in the example of Figure 9) (A3 shown in Figure 9).

[0058] If the controller 30 itself malfunctions, the output becomes zero and the bleed valve 86 closes. On the other hand, if the controller 30 is not malfunctioning, the controller 30 may control the output to zero. For example, to ensure sufficient pressure for travel, slewing, and boom raising / lowering, the system 100 may be equipped with an unload valve that is not electrically controlled.

[0059] When the redundant operation system switching unit 75 is switched to the active position, the controller 30 limits the maximum opening area of ​​the control valves (in the example of Figure 9, the slewing control valve 51 and the boom control valve 52) so that they do not open beyond a preset fixed opening area. For example, when the redundant operation system active switch is turned on, the controller 30 creates a redundant signal using a resistor 76 that reduces the battery voltage to a predetermined voltage, thereby limiting the opening area of ​​the control valves when the actuators are operated by the redundant operation system (in the example of Figure 8, the slewing redundant operation switch 71 and the boom redundant operation switch 72) (A4 shown in Figure 8). The resistance value of this resistor 76 determines the opening area of ​​the control valves when limp-homed.

[0060] When the redundant operating system switching unit 75 is effectively switched on, or when the controller 30 (main controller 30) that controls the control valve fails, the engine speed limit is restricted to a predetermined value or less. For example, if the main controller 30 fails, the engine controller 35 restricts the engine speed limit to a predetermined value or less (A5 shown in Figure 8). As a result, even if the main controller 30 fails, the engine 32 can continue to operate.

[0061] On the other hand, if the main controller 30 is not malfunctioning, the main controller 30 determines that the redundant operation system enable switch has been turned on and limits the engine speed so that the upper limit of the engine speed is below a predetermined value.

[0062] For example, the main controller 30 and the engine controller 35 may communicate with each other. If, due to this communication, the engine controller 35 loses the ability to recognize the main controller 30, the engine controller 35 will determine that the main controller 30 has malfunctioned and will limit the engine speed.

[0063] When the redundant operation system switching unit 75 is effectively switched on, or when the main controller 30 fails, the throttle dial 46 can be operated to set the engine speed to a speed below the upper limit.

[0064] If the signals from electric levers 1 and 2 are not at normal values, the controller 30 determines that there is an abnormality in the signals from electric levers 1 and 2 and forcibly stops the actuator assigned to the signal that was determined to be abnormal. Subsequently, if the redundant operation system switching unit 75 is switched to a valid state, it becomes possible to operate the actuator using the redundant operation system.

[0065] Figure 10 shows an example of a signal from an electrical control unit according to the first embodiment. In Figure 10, an example of a lever signal is shown as a signal from the electrical control unit. In the following description, the first operation signal will be referred to as the main signal, and the second operation signal will be referred to as the sub-signal. As shown in Figure 10, if a voltage value of, for example, 0.3V or less, or 4.7V or more is detected for the main signal voltage (lever sensor voltage of the main signal), it is determined that the main signal is abnormal. Similarly, if a voltage value of, for example, 0.3V or less, or 4.7V or more is detected for the sub-signal voltage (lever sensor voltage of the sub-signal), it is determined that the sub-signal is abnormal. When the lever signal is at a normal value, the sum of the voltage values ​​of the main signal and the sub-signal will be approximately 5V. Therefore, if the sum of the voltage values ​​of the main signal and the sub-signal deviates from a predetermined value of 5V, it is determined that the lever signal is abnormal.

[0066] For example, the controller 30 has a function to determine whether or not an electrical control unit is malfunctioning. If the controller 30 determines that an electrical control unit is malfunctioning, it will forcibly stop the actuator (for travel, slewing, work equipment, etc.) assigned to that actuator, and will set the valve control output to zero.

[0067] When the redundant control system switching unit 75 is switched to a more effective state, the controller 30 notifies the operator that the redundant control system switching unit 75 has been switched to a more effective state. For example, the display device 45 has a function to notify the operator that the redundant control system switching unit 75 has been switched to a more effective state.

[0068] Figure 11 shows an example of how the operator is notified that the redundant operation system switching unit 75 according to the first embodiment has been successfully switched over. As shown in Figure 11, for example, when the redundant control system enable switch is turned on, the display device 45 will display "Redundant control system enable switch is active". The screen below "Redundant control system enable switch is active" may also display instructions on how to operate the switch to enable the normal control system.

[0069] <Effects and Effects> As described above, the system 100 of this embodiment is a system for controlling a work machine 1, and comprises actuators 10L, 10R, 11, 12, 13, 14 for driving the work machine 1, control valves 50L, 50R, 51, 52, 53, 54 for operating the actuators 10L, 10R, 11, 12, 13, 14, a controller 30 that controls the control valves based on signals from electrical operating units 42L, 42R, 43L, 43R, a redundant operating system 70L, 70R, 71, 72, 73, 74 separate from the controller 30, and a redundant operating system switching unit 75 for enabling the operation of the actuators 10L, 10R, 11, 12, 13, 14 by the redundant operating systems 70L, 70R, 71, 72, 73, 74. With this configuration, by effectively switching the redundant control system switching unit 75, it becomes possible to operate actuators 10L, 10R, 11, 12, 13, and 14 from redundant control systems 70L, 70R, 71, 72, 73, and 74, which are separate from the controller 30. Therefore, it is possible to maintain a minimum level of functionality so that the malfunctioning work machine 1 can be moved to the repair location.

[0070] In this embodiment, when the redundant operation system switching unit 75 is effectively switched, the controller 30 prohibits the operation of actuators 10L, 10R, 11, 12, 13, and 14 based on signals from the electrical operation units 42L, 42R, 43L, and 43R. With this configuration, if it becomes possible to operate actuators 10L, 10R, 11, 12, 13, and 14 from redundant operating systems 70L, 70R, 71, 72, 73, and 74 separate from the controller 30, it is possible to prevent the actuators 10L, 10R, 11, 12, 13, and 14 from being operated unintentionally by the electrical operating units 42L, 42R, 43L, and 43R.

[0071] In this embodiment, when the redundant operation system switching unit 75 is effectively switched, the controller 30 sets the capacity of the pump 33 that pumps the working fluid to a preset fixed capacity. This configuration allows the pump 33 to maintain its function more safely compared to when its capacity is set to its maximum capacity.

[0072] In this embodiment, the controller 30 is set to a capacity that allows the actuators 10L, 10R, 11, 12, 13, and 14 to operate at the minimum required speed. With this configuration, reducing the fixed capacity slows down the speed of actuators 10L, 10R, 11, 12, 13, and 14, allowing for safer maintenance of functionality.

[0073] In this embodiment, the system 100 further includes a bleed valve 86 between the circuit between the pump 33 that pumps the working fluid and the control valves 50L, 50R, 51, 52, 53, 54 and the tank 85, which releases a portion of the working fluid pumped by the pump 33 into the tank 85. When the redundant operating system switching unit 75 is effectively switched, the controller 30 sets the opening area of ​​the bleed valve 86 so that the working fluid can be supplied from the pump 33 at a pressure that enables the actuators 10L, 10R, 11, 12, 13, 14 to operate. With this configuration, the bleed valve 86 releases a portion of the working fluid into the tank 85, which prevents the pressure required to operate actuators 10L, 10R, 11, 12, 13, and 14 from rising excessively, thus preventing dangerous behavior. Furthermore, by setting the opening area of ​​the bleed valve 86, actuators 10L, 10R, 11, 12, 13, and 14 can operate sufficiently at the pressure required for operation.

[0074] In this embodiment, when the redundant operation system switching unit 75 is effectively switched, the controller 30 restricts the maximum opening area of ​​the control valves 50L, 50R, 51, 52, 53, and 54 so that it does not open to a fixed opening area set in advance. With this configuration, compared to when the opening areas of control valves 50L, 50R, 51, 52, 53, and 54 are opened to their maximum opening areas, the flow rate and pressure supplied to the actuator are reduced, and the actuator speed is prevented from increasing excessively, thus allowing the system to maintain its function more safely.

[0075] In this embodiment, if the redundant operation system switching unit 75 is effectively switched, or if the controller 30 that controls the control valves 50L, 50R, 51, 52, 53, 54 fails, the upper limit of the engine speed is limited to a predetermined value or less. This configuration suppresses excessive increases in engine speed, thereby reducing the flow rate supplied to the actuator and preventing the actuator's speed from increasing excessively, thus preventing dangerous behavior.

[0076] In this embodiment, the system 100 further includes a throttle dial 46 capable of adjusting the engine speed. When the redundant operating system switching unit 75 is effectively switched, or when the controller 30 that controls the control valves 50L, 50R, 51, 52, 53, 54 fails, the throttle dial 46 can be operated to set the engine speed to a speed below the upper limit. For example, if the pump capacity is fixed, the speed cannot be adjusted during limp-home. In contrast, according to this embodiment, the pump discharge flow rate can be adjusted by adjusting the engine speed by operating the throttle dial 46, so the speed can be adjusted even during limp-home.

[0077] In this embodiment, the controller 30 determines whether the electrical control units 42L, 42R, 43L, and 43R are malfunctioning based on the signals from the electrical control units 42L, 42R, 43L, and 43R, and forcibly stops the actuators 10L, 10R, 11, 12, 13, and 14 that are assigned to the signals of the electrical control units determined to be malfunctioning. When the redundant control system switching unit 75 is effectively switched, it becomes possible to operate the actuators 10L, 10R, 11, 12, 13, and 14 from the redundant control systems 70L, 70R, 71, 72, 73, and 74. With this configuration, after actuators 10L, 10R, 11, 12, 13, and 14, which are assigned to signals from an electrical control unit determined to be in a faulty state, are forcibly stopped, it becomes possible to operate actuators 10L, 10R, 11, 12, 13, and 14 from redundant control systems 70L, 70R, 71, 72, 73, and 74, thus maintaining functionality more safely.

[0078] In this embodiment, when the redundant operation system switching unit 75 is effectively switched, the controller 30 notifies the operator that the redundant operation system switching unit 75 has been effectively switched. With this configuration, the operator can be informed that the redundant operating system switching unit 75 has been effectively switched over, thus alerting the operator.

[0079] <Variation> In the above embodiment, an example was given in which, when the redundant operating system switching unit is effectively switched, the controller prohibits the operation of the actuator based on the signal of the electrical operating unit, but the embodiment is not limited to this. For example, when the redundant operating system switching unit is effectively switched, the controller may allow (or may not prohibit) the operation of the actuator based on the signal of the electrical operating unit. When the redundant operating system switching unit is effectively switched, the manner in which the actuator is operated based on the signal of the electrical operating unit can be changed according to the design specifications.

[0080] In the above embodiment, the controller was described as being set to a capacity that allows the actuator to operate at the minimum required speed, but it is not limited to this. For example, the controller may reduce the battery voltage with a resistor, similar to a valve, and fix the capacity to any desired value by connecting the reduced voltage signal to the pump control valve. The fixed capacity can be changed according to the design specifications.

[0081] In the above embodiment, the system further includes a bleed valve between the circuit between the pump that pumps the working fluid and the control valve and the tank, which releases a portion of the working fluid pumped by the pump into the tank, and when the redundant operating system switching unit is effectively switched, the controller sets the opening area of ​​the bleed valve so that the working fluid can be supplied from the pump at a pressure that enables the actuator to operate, but the system is not limited to this example. For example, the working fluid can be supplied from the pump at a pressure that enables the actuator to operate by changing the capacity of the pump. For example, the opening of the bleed valve may be closed. For example, the manner in which the opening area of ​​the bleed valve is set can be changed according to the design specifications.

[0082] In the above embodiment, when the redundant operating system switching unit is effectively switched, the controller is described as limiting the maximum opening area of ​​the control valve so that it does not open beyond a preset fixed opening area, but the embodiment is not limited to this. For example, the opening area of ​​the control valve may be opened to the maximum opening area. The manner in which the opening area of ​​the control valve is set can be changed according to the design specifications.

[0083] In the above embodiment, an example was given in which the upper limit of the engine speed is restricted to a predetermined value or less when the redundant operating system switching unit is effectively switched or when the controller that controls the control valve fails, but the invention is not limited to this. For example, when the redundant operating system switching unit is effectively switched or when the controller that controls the control valve fails, the engine speed may be arbitrarily changed. The manner in which the engine speed is set can be changed according to the design specifications.

[0084] In the above embodiment, the system further includes a throttle dial capable of adjusting the engine speed, and when the redundant operating system switching unit is effectively switched, or when the controller controlling the control valve fails, the throttle dial is operated to set the engine speed to a speed below the upper limit. However, the system is not limited to this example. For example, when the redundant operating system switching unit is effectively switched, or when the controller controlling the control valve fails, the engine speed may be set by an operator other than the throttle dial. The method of setting the engine speed can be changed according to the design specifications.

[0085] In the above embodiment, the controller determines whether an electrical control unit is malfunctioning based on the signal from the electrical control unit, forcibly stops the actuator assigned to the signal of the electrical control unit determined to be malfunctioning, and allows the actuator to be operated by the redundant control system when the redundant control system switching unit is effectively switched. However, the embodiment is not limited to this. For example, the actuator assigned to the signal of the electrical control unit determined to be malfunctioning may be allowed to drive (without being forcibly stopped), and the actuator may be operated by the effectively switched redundant control system. The manner in which the actuator assigned to the signal of the electrical control unit determined to be malfunctioning is operated by the redundant control system can be changed according to the design specifications.

[0086] In the above embodiment, an example was given in which the controller notifies the operator that the redundant operating system switching unit has been effectively switched over, but the embodiment is not limited to this. For example, the controller does not need to notify the operator that the redundant operating system switching unit has been effectively switched over. The manner of notification can be changed according to the design specifications.

[0087] <Second Embodiment> Figure 12 is a diagram illustrating an example of control of a work machine according to the second embodiment. Figure 13 is a diagram illustrating an example of control of a work machine following Figure 12. Hereinafter, an example of control of a work machine according to the second embodiment will be described with reference to Figures 12 and 13 together. In the configurations shown in Figures 12 and 13, the same reference numerals are used for components similar to those in the embodiments described above, and their detailed descriptions are omitted.

[0088] In this embodiment, the machine includes left and right travel motors 10L and 10R for moving the travel body 2 of the work machine forward and backward, and for operating the left and right tracks 5L and 5R of the travel body 2 in different directions, EPC valves 60 (left and right travel EPC valves 60LF, 60LR, 60RF, 60RR) for controlling the left and right travel motors 10L and 10R respectively, electrical operating units (left and right travel levers / pedals 43L, 43R) for operating the left and right travel motors 10L and 10R respectively, and a controller 30.

[0089] The controller 30 has a function to determine abnormalities in the signals from the electrical operating section (left and right travel levers / pedals 43L, 43R) and the control signals from the EPC valves 60 (left and right travel EPC valves 60LF, 60LR, 60RF, 60RR).

[0090] For example, in the same manner as in the first embodiment, if an abnormality in the signals of the left and right driving levers / pedals is detected as a voltage value of, for example, 0.3V or less, or 4.7V or more as the main signal voltage, it is determined that there is an abnormality in the main signals of the left and right driving levers / pedals (the same applies to the sub-signals). Also, if the sum of the voltage values ​​of the main signal and the sub-signal deviates from a predetermined value of 5V, it is determined that there is an abnormality in the signals of the left and right driving levers / pedals (see Figure 10).

[0091] For example, abnormalities in the control signals of the left and right travel EPC valves 60LF, 60LR, 60RF, and 60RR can be seen in the following cases (1) to (3). (1) Despite the output current command value being sufficiently large, the measured current value is small (wire break detected). (2) The current value measured when the output is turned on is very large (ground fault, short circuit detected). (3) Despite the output being off, the terminal voltage is rising (short circuit to the power supply).

[0092] If the controller 30 determines that there is an abnormality in either the signal from the left or right travel levers / pedals 43L, 43R, or in the control signals from the left or right travel EPC valves 60LF, 60LR, 60RF, 60RR, it will stop both the left and right travel motors 10L, 10R. For example, if the controller 30 determines that there is an abnormality in the signal from the left travel lever / pedal 43L, it will stop all travel operations in the left, right, forward, and backward directions (B1 shown in Figure 12).

[0093] Subsequently, when the redundant operation system switching unit 75 is switched to the active position, the controller 30 allows operation in the opposite direction to the direction in which the abnormality occurred for the motor controlled by the signal determined to be abnormal among the left and right travel motors 10L and 10R. The controller 30 also allows operation in any direction for the motors controlled by signals that have not been determined to be abnormal among the left and right travel motors 10L and 10R. For example, if the controller 30 determines that there is an abnormality in the signal indicating reverse for the left travel lever / pedal 43L, it stops both the left and right travel motors 10L and 10R. Subsequently, when the redundant operation system activation switch is turned on, the controller 30 continues to stop the reverse movement of the left travel motor 10L, but allows operation of the forward movement of the right travel motor 10R, the reverse movement of the right travel motor 10R, and the forward movement of the left travel motor 10L, which have not been determined to be abnormal (B2 shown in Figure 12). The above example illustrates a case where an abnormality was detected in the lever signal; however, the same procedure should be followed if an abnormality is detected in the EPC output signal.

[0094] As described above, the system 100 of this embodiment includes left and right travel motors 10L and 10R for moving the travel body 2 of the work machine forward and backward, and for operating the left and right tracks 5L and 5R of the travel body 2 in different directions, EPC valves 60 (left and right travel EPC valves 60LF, 60LR, 60RF, 60RR) for controlling the left and right travel motors 10L and 10R respectively, electrical operating units (left and right travel levers / pedals 43L, 43R) for operating the left and right travel motors 10L and 10R respectively, and a controller 30. The controller 30 stops both the left and right travel motors 10L and 10R if it determines that there is an abnormality in the signal from the electrical operating unit (left and right travel levers / pedals 43L, 43R) or the control signal from the EPC valves 60 (left and right travel EPC valves 60LF, 60LR, 60RF, 60RR). For example, if an abnormality is detected in any of the signals from the electrical control unit or in any of the control signals from the EPC valve 60, stopping only one of the left and right travel motors 10L and 10R may be undesirable. For instance, if the vehicle 2 is moving forward and only one motor is stopped while the other motor continues to operate, the vehicle body will suddenly turn, which is undesirable. In contrast, in this embodiment, if an abnormality is detected in any of the signals from the electrical control unit or in any of the control signals from the EPC valve 60, stopping both the left and right travel motors 10L and 10R is preferable for safely maintaining functionality.

[0095] In this embodiment, if the controller 30 determines that there is an abnormality in either the signal of the electrical operation unit or the control signal of the EPC valve 60 and stops both the left and right travel motors 10L and 10R, and then the redundant operation system switching unit 75 is effectively switched, the controller 30 permits operation in the opposite direction to the direction in which the abnormality occurred for the motor controlled by the signal that was determined to be abnormal, and permits operation in any direction for the motor controlled by the signal that was not determined to be abnormal. For example, even if one of the left and right travel motors 10L and 10R stops moving in a predetermined direction, the work machine can still be moved to the repair location by changing direction using the swivel action of the swivel body 3. With this configuration, the operator can recognize that an abnormality has occurred and then activate the redundant operation system switching unit 75 to enable operation of the operational motor. Therefore, the function can be maintained more safely.

[0096] <Third Embodiment> Figure 14 is a diagram illustrating an example of control of a work machine according to the third embodiment. Figure 15 is a diagram illustrating an example of control of a work machine following Figure 14. Hereinafter, an example of control of a work machine according to the third embodiment will be described with reference to Figures 14 and 15 together. In the configurations shown in Figures 14 and 15, the same reference numerals are used for components similar to those in the embodiments described above, and their detailed descriptions are omitted.

[0097] In this embodiment, the system includes a PPC lock setting unit 90 (PPC lock switch in the example of Figure 14) for setting the supply or shutoff of working fluid from the pilot pump 34 to a plurality of EPC valves 60 (in the example of Figure 15, swivel EPC valves 61L, 61R, boom EPC valves 62U, 62D), and a PPC source pressure lock solenoid valve 91 that supplies or shuts off the working fluid discharged from the pilot pump 34 to the plurality of EPC valves 60 based on a control signal from the controller 30. The PPC source pressure lock solenoid valve 91 supplies the working fluid discharged from the pilot pump 34 to the plurality of EPC valves 60 when a voltage is applied to the solenoid, and shuts off the working fluid discharged from the pilot pump 34 and does not supply it to the plurality of EPC valves 60 when no voltage is applied to the solenoid.

[0098] For example, the controller 30 has a function to determine whether or not the PPC lock setting unit 90 is malfunctioning. If the controller 30 determines that the PPC lock setting unit 90 is malfunctioning, it operates the PPC source pressure lock solenoid valve 91 to the shut-off state and stops outputting the control signal for controlling the actuator.

[0099] For example, the controller 30 acquires two inputs: one signal that goes high when the PPC lock switch is on and another signal that goes high when it is off. If both signals are in an abnormal combination such as on / on or off / off, the controller determines that the PPC lock setting unit 90 is in a faulty state (C1 shown in Figure 14).

[0100] For example, if the controller 30 determines that the PPC lock setting unit 90 is in a faulty state, it operates the PPC main pressure lock solenoid valve 91 to a shut-off state (not supplying the working fluid discharged from the pilot pump 34 to the multiple EPC valves 60) and stops outputting control signals to all EPC valves (C2 shown in Figure 14). For example, if the PPC main pressure lock control signal becomes LOW (off), the PPC main pressure lock solenoid valve 91 is shut off, and even if control signals are being output to the EPC valves, the control valves will not operate.

[0101] When the redundant operating system switching unit 75 is switched to a more effective state, the controller 30 enables the control output of the actuator that was stopped due to the PPC lock setting unit 90 determining that it was in a faulty state to be output again. For example, when the redundant operating system enable switch is turned on, the controller 30 enables the output of the control signal to the EPC valve again (C3 shown in Figure 14).

[0102] Even when the redundant operating system switching unit 75 is switched to an active state, the controller 30 does not release the PPC source pressure lock solenoid valve 91, which has been shut off due to the PPC lock setting unit 90 being determined to be in a faulty state, from the shut-off state. For example, when the redundant operating system active switch is turned on, the controller 30 allows the output of control signals to the EPC valves to be re-output, but prevents the release of the restriction on supplying the working fluid discharged from the pilot pump 34 to the multiple EPC valves 60 (C4 shown in Figure 14).

[0103] In this embodiment, a PPC lock release unit 92 (PPC automatic lock release switch in the example of Figure 14) is provided, which enables the lock of the PPC source pressure lock solenoid valve 91 to be released even when the PPC lock setting unit 90 is determined to be in a malfunction state.

[0104] The PPC main pressure lock solenoid valve 91, which has been shut off due to the PPC lock setting unit 90 being determined to be in a faulty state, can be released from its shut-off state by activating the PPC lock release unit 92. For example, when the PPC automatic lock release switch is turned on, it becomes possible to release the shut-off state of the PPC main pressure lock solenoid valve 91 independently of the controller 30 (C5 shown in Figure 14).

[0105] As described above, this embodiment includes a PPC lock setting unit 90 for setting the shut-off and release of the pilot pressure source pressure for operating actuators 10L, 10R, 11, 12, 13, and 14, and a PPC source pressure lock solenoid valve 91 that shuts off and releases the pilot pressure source pressure in response to a signal from the controller 30. The controller 30 has a function to determine whether or not the PPC lock setting unit 90 is malfunctioning. If the controller 30 determines that the PPC lock setting unit 90 is malfunctioning, it operates the PPC source pressure lock solenoid valve 91 to the shut-off state and stops the output that controls actuators 10L, 10R, 11, 12, 13, and 14. With this configuration, if the PPC lock setting unit 90 fails, the pilot pressure source can be shut off, and the control outputs of actuators 10L, 10R, 11, 12, 13, and 14 can be stopped. This redundancy provides a safer solution.

[0106] In this embodiment, when the redundant operation system switching unit 75 is effectively switched, the controller 30 enables the control outputs of actuators 10L, 10R, 11, 12, 13, and 14, which were stopped due to the PPC lock setting unit 90 being determined to be in a faulty state, to be output again. With this configuration, if the PPC lock setting unit 90 fails, the control outputs of actuators 10L, 10R, 11, 12, 13, and 14 are temporarily suspended, and the redundant operating system switching unit 75 is enabled, allowing the outputs to be restored. Therefore, the function can be maintained more safely.

[0107] In this embodiment, even when the redundant operation system switching unit 75 is effectively switched, the controller 30 does not release the PPC source pressure lock solenoid valve 91, which has been shut off due to the PPC lock setting unit 90 being determined to be in a faulty state, from the shut-off state. With this configuration, by effectively switching the redundant operating system switching unit 75, when the control outputs of actuators 10L, 10R, 11, 12, 13, and 14 become available again, the PPC main pressure lock solenoid valve 91 can be prevented from releasing the pilot pressure. For example, even if the operator recognizes that the PPC main pressure lock solenoid valve 91 is in the shut-off state, they can prevent the actuators 10L, 10R, 11, 12, 13, and 14 from moving unexpectedly by effectively switching the redundant operating system switching unit 75.

[0108] In this embodiment, a PPC lock release unit 92 is provided that enables the lock of the PPC main pressure lock solenoid valve 91 to be released even when the PPC lock setting unit 90 is determined to be in a malfunction state. The PPC main pressure lock solenoid valve 91, which has been shut off due to the PPC lock setting unit 90 being determined to be in a malfunction state, can be released from the shut-off state by activating the PPC lock release unit 92. This configuration prevents the PPC main pressure lock solenoid valve 91 from being unlocked unintentionally by the operator. For example, by providing the PPC unlock unit 92 separately from the redundant operating system switching unit 75, the operator will operate the PPC unlock unit 92 with a clear intention to release the shut-off state of the PPC main pressure lock solenoid valve 91. Therefore, the release of the shut-off state of the PPC main pressure lock solenoid valve 91 unintentionally can be avoided.

[0109] <Fourth Embodiment> Figure 16 is a diagram illustrating an example of the control of a work machine according to the fourth embodiment. Figure 17 is a diagram illustrating an example of setting an operation pattern according to the fourth embodiment. Hereinafter, an example of the control of a work machine according to the fourth embodiment will be described with reference to Figures 16 and 17 together. In the configurations shown in Figures 16 and 17, the same reference numerals are used for components that are the same as those in the embodiments described above, and their detailed descriptions are omitted. In Figure 16, lever 1 and lever 2 are shown as multiple electric levers (electric operating parts).

[0110] In this embodiment, a setting input device 45 is provided for setting the signal assignments of levers 1 and 2 corresponding to actuators. The setting input device 45 makes it possible to assign a different operation input signal as the signal for operating the actuator in the event that a failure occurs in the controller 30 that prevents it from recognizing the operation input signals from levers 1 and 2 corresponding to one or more actuators.

[0111] For example, the display device 45 functions as a setting input device 45 for setting the signal assignments for levers 1 and 2 corresponding to the actuators. For example, the monitor acting as the display device 45 displays a screen for changing the lever signal assignments. For example, the signal assigned to raising the boom is normally lever 1-A, but in the event of an abnormality, it is set to be assigned to a different signal (lever 2-A in the example of Figure 17) (operation pattern setting). For example, the signal assigned to slewing left is normally lever 2-A, but in the event of an abnormality, it is set to be assigned to a different signal (lever 1-A in the example of Figure 17).

[0112] For example, if the A signal of lever 1 (lever 1-A shown in Figure 17) is initially assigned to the boom raising operation, and the A signal of lever 1 fails, the boom raising operation can be reassigned to the A signal of lever 2 (lever 2-A shown in Figure 17), allowing the boom raising operation to continue using lever 2 (D1 shown in Figure 16).

[0113] When the redundant operation system switching unit 75 is switched to the active position, the setting input device 45 allows another operation input signal to be assigned as the signal for operating the actuator. For example, when the redundant operation system enable switch is turned on, the controller 30 allows the change in the lever signal assignment (D2 shown in Figure 16).

[0114] For example, the controller 30 has a function to determine whether levers 1 and 2 are malfunctioning. The controller 30 determines that levers 1 and 2 are malfunctioning if the signals from levers 1 and 2 are not at normal values. The controller 30 forcibly stops the actuator assigned to the signal of the lever determined to be malfunctioning. When the redundant operation system switching unit 75 is switched to a more active state, the setting input device 45 allows another operation input signal to be assigned as the signal for operating the actuator. When the controller 30 forcibly stops the actuator (for travel, slewing, work equipment, etc.) assigned to the signal of the lever determined to be malfunctioning, it sets the valve control output to zero.

[0115] For example, a fault in the signals of levers 1 and 2 is determined to be a main signal fault when a voltage value of, for example, 0.3V or less, or 4.7V or more is detected as the main signal voltage, similar to the first embodiment (the same applies to the sub-signals). Also, if the sum of the voltage values ​​of the main signal and the sub-signals deviates from a predetermined value of 5V, a lever signal fault is determined (see Figure 10).

[0116] For example, if the controller 30 determines that the lever signal is faulty, it will temporarily turn off the output. Subsequently, if the redundant operation system enable switch is turned on, the controller 30 will enable operation again using the lever signal with the changed assignment (D3 shown in Figure 16).

[0117] In this embodiment, the system includes a display device 45 that displays a screen for changing the signal assignments of levers 1 and 2, and an authorization operation unit 45a that authorizes the change in the signal assignments of levers 1 and 2. When the authorization operation unit 45a is operated to authorize the change in the signal assignments of levers 1 and 2, the setting input device 45 makes it possible to assign another operation input signal as a signal for operating the actuator.

[0118] For example, the operator is notified via a monitor, which acts as a display device 45, and when the operator presses the authorization operation unit 45a (for example, a button displayed on the monitor), the lever assignment change becomes effective (D4 shown in Figure 16).

[0119] As described above, this embodiment includes a setting input device 45 for setting the signal assignments of the electrical operating units 42L, 42R, 43L, and 43R corresponding to the actuators 10L, 10R, 11, 12, 13, and 14. The setting input device 45 makes it possible to assign a different operating input signal as the operating signal for actuators 10L, 10R, 11, 12, 13, and 14 in the event of a failure in the controller 30 that prevents it from recognizing the operating input signals corresponding to one or more actuators 10L, 10R, 11, 12, 13, and 14. This configuration allows for changing the assignment of operation input signals in the event of a malfunction. By assigning the signals from the functioning electrical control units 42L, 42R, 43L, and 43R to the actuators 10L, 10R, 11, 12, 13, and 14 that you want to operate, you can control the assigned actuators 10L, 10R, 11, 12, 13, and 14.

[0120] In this embodiment, when the redundant operation system switching unit 75 is effectively switched, the setting input device 45 can assign another operation input signal as the signal for operating actuators 10L, 10R, 11, 12, 13, and 14. With this configuration, in the event of a failure, the assignment of operation input signals becomes possible when the redundant operation system switching unit 75 is effectively switched on. This allows the assignment function to be enabled when the redundant operation system switching unit 75 is enabled in the event of a failure.

[0121] In this embodiment, the controller 30 determines whether the electrical operating units 42L, 42R, 43L, and 43R are malfunctioning based on the signals from the electrical operating units 42L, 42R, 43L, and 43R, and forcibly stops the actuators 10L, 10R, 11, 12, 13, and 14 that are assigned to the signals of the electrical operating units that are determined to be malfunctioning. When the redundant operating system switching unit 75 is effectively switched, the setting input device 45 makes it possible to assign a different operation input signal as the signal for operating the actuators 10L, 10R, 11, 12, 13, and 14. With this configuration, when a failure is detected in the electrical control units 42L, 42R, 43L, and 43R, the actuators 10L, 10R, 11, 12, 13, and 14 are temporarily stopped. Then, by switching the redundant control system switching unit 75 to active, they can be operated again by a different signal with a changed assignment. Therefore, even in the event of a failure, the operation of actuators 10L, 10R, 11, 12, 13, and 14 can continue.

[0122] In this embodiment, the system includes a display device 45 that displays a screen for changing the signal assignments of the electrical control units 42L, 42R, 43L, and 43R, and an authorization operation unit 45a that authorizes the change in the signal assignments of the electrical control units 42L, 42R, 43L, and 43R. When the authorization operation unit 45a is operated to authorize the change in the signal assignments of the electrical control units 42L, 42R, 43L, and 43R, the setting input device 45 makes it possible to assign a different operation input signal as the signal for operating the actuators 10L, 10R, 11, 12, 13, and 14. With this configuration, the operator is notified by the display device 45, and the authorization operation unit 45a is operated, which allows the assignment of the operation input signals to be changed.

[0123] <Fifth Embodiment> Figure 18 illustrates an example of the control of a work machine according to the fifth embodiment. Hereinafter, an example of the control of a work machine according to the fifth embodiment will be described with reference to Figure 18. In the configuration shown in Figure 18, components similar to those in the embodiments described above are denoted by the same reference numerals, and their detailed descriptions are omitted. In Figure 18, lever 1 and lever 2 are shown as multiple electric levers (electric operating parts).

[0124] In this embodiment, levers 1 and 2 transmit to the controller 30 a main signal (an example of a first operation signal) in which the detected input amount changes from a first value to a second value greater than the first value, and a sub-signal (an example of a second operation signal) in the opposite direction to the main signal, changing from the second value to the first value. Lever 1 and 2 transmit the main signal and sub-signal, respectively (see Figure 10).

[0125] When the redundant operation system switching unit 75 is switched to the disabled state, the controller 30 enables operation of the control valve using the main signals from levers 1 and 2. When the redundant operation system switching unit 75 is switched to the enabled state, the controller 30 enables operation of the control valve using the sub-signals from levers 1 and 2. For example, when the redundant operation system enable switch is turned off, the controller 30 enables operation of the control valve using the main signal from lever 1. On the other hand, when the redundant operation system enable switch is turned on, the controller 30 enables operation of the control valve using the sub-signal from lever 1 (E1 shown in Figure 18).

[0126] For example, the controller 30 has a function to determine whether levers 1 and 2 are malfunctioning. The controller 30 determines that levers 1 and 2 are malfunctioning if the main signals of levers 1 and 2 are not at normal values. If the controller 30 determines that there is an abnormality in the main signals of predetermined levers 1 and 2 during operation of the work machine, it forcibly stops the actuator operated by the main signal. When the controller 30 forcibly stops the actuator (for travel, slewing, work machine, etc.) assigned to the signal of the lever determined to be malfunctioning, it sets the valve control output to zero. When the redundant operation system switching unit 75 is effectively switched, the controller 30 makes the control valves operable by the sub-signals of levers 1 and 2.

[0127] For example, a malfunction in the main signals (and sub-signals) of levers 1 and 2 is determined to be a signal malfunction when a signal voltage of, for example, 0.3V or less, or 4.7V or more, is detected, similar to the first embodiment (see Figure 10).

[0128] For example, if the controller 30 determines that the main signal has failed, it will temporarily turn off the output. Subsequently, if the redundant operation system enable switch is turned on, the controller 30 will enable operation again via the sub-signal (E2 shown in Figure 18).

[0129] As described above, in this embodiment, the electrical operating units 42L, 42R, 43L, and 43R transmit to the controller 30 a first operating signal in which the input amount detected according to the operating amount changes from a first value to a second value greater than the first value, and a second operating signal in which, conversely to the first operating signal, changes from the second value to the first value. When the redundant operating system switching unit 75 is switched to disabled, the controller 30 makes the control valves 50L, 50R, 51, 52, 53, and 54 operable by either the first operating signal or the second operating signal of the electrical operating units 42L, 42R, 43L, and 43R. When the redundant operating system switching unit 75 is switched to enabled, the controller 30 makes the control valves 50L, 50R, 51, 52, 53, and 54 operable by signals in the electrical operating units 42L, 42R, 43L, and 43R that are the opposite of the signals used when the redundant operating system switching unit 75 was disabled. With this configuration, the redundant signals for the electrical control units 42L, 42R, 43L, and 43R can be the opposite of the signals used when the redundant control system switching unit 75 is disabled. For example, under normal conditions, the first operation signal is used as the signal for the electrical control units 42L, 42R, 43L, and 43R to operate the control valves 50L, 50R, 51, 52, 53, and 54, thereby enabling the operation of the corresponding actuators 10L, 10R, 11, 12, 13, and 14. On the other hand, in the event of a failure of the first operation signal, operation becomes possible using the second operation signal. That is, by turning on the redundant control system switching unit 75 in the event of a failure, operation becomes possible using the opposite of the signals used when the redundant control system switching unit 75 is disabled.

[0130] In this embodiment, the controller 30 determines whether or not the electrical operating units 42L, 42R, 43L, and 43R are malfunctioning. If the first operating signal of the electrical operating units 42L, 42R, 43L, and 43R is not of a normal value, the controller 30 determines that the first operating signal of the predetermined electrical operating units 42L, 42R, 43L, and 43R is abnormal when operating the work machine, and forcibly stops the actuators 10L, 10R, 11, 12, 13, and 14 that are operated by the first operating signal. If the redundant operating system switching unit 75 is effectively switched, the controller 30 makes the control valves 50L, 50R, 51, 52, 53, and 54 operable by the second operating signal of the electrical operating units 42L, 42R, 43L, and 43R. With this configuration, when a failure is detected in the first operation signal of the electrical operation units 42L, 42R, 43L, and 43R, the corresponding actuators 10L, 10R, 11, 12, 13, and 14 are temporarily stopped. Then, by switching the redundant operation system switching unit 75 to active, they become operable again by the second operation signal. Therefore, even in the event of a failure, the operation of actuators 10L, 10R, 11, 12, 13, and 14 can continue.

[0131] <Other variations> In the embodiments described above, the system was explained using a hydraulic excavator as an example of a working machine, but it is not limited to this. For example, the working machine may be other working machines such as a wheel loader, bulldozer, or dump truck. The target to which the system is applied can be changed as appropriate.

[0132] Although one embodiment has been described above with reference to the drawings, the specific configuration is not limited to that described above. Additions, omissions, substitutions, and other modifications to the configuration are possible without departing from the spirit of this disclosure, and the above-described embodiments can be combined as appropriate. [Explanation of Symbols]

[0133] 1...Work machine, 2...Traction unit, 3...Slewing unit, 4...Work machine, 5L, 5R...Tracks, 10L, 10R...Traction motor (actuator), 11...Slewing motor (actuator), 12...Boom cylinder (actuator), 13...Arm cylinder (actuator), 14...Attachment cylinder (actuator), 30...Controller, 33...Pump (main pump), 42L, 42R...Operating lever (electrical control unit), 43L, 43R...Traction lever / pedal (electrical control unit), 45...Display device, setting input device, 45a...Permission operation unit, 46...Throttle dial, 50L, 50R...Traction control valve (control valve), 51...Slewing control valve (control valve), 52...Boom control valve (control valve), 53...Arm control valve (control valve) 54…Attachment control valve (control valve), 60LF, 60LR, 60RF, 60RR…Travel EPC valve, 61L, 61R…Slewing EPC valve, 62U, 62D…Boom EPC valve, 63U, 63D…Arm EPC valve, 64U, 64D…Bucket EPC valve, 70L, 70R…Travel redundant operation switch (redundant operation system), 71…Slewing redundant operation switch (redundant operation system), 72…Boom redundant operation switch (redundant operation system), 73…Arm redundant operation switch (redundant operation system), 74…Attachment redundant operation switch (redundant operation system), 75…Redundant operation system switching unit, 82~85…Tank, 86…Bleed valve, 90…PPC lock setting unit, 91…PPC main pressure lock solenoid valve, 92…PPC lock release unit, 100…System

Claims

1. A system for controlling working machinery, An actuator for driving the aforementioned work machine, A control valve for operating the actuator, A controller that controls the control valve based on a signal from the electrical operating unit, A redundant operating system separate from the aforementioned controller, The system includes a redundant operating system switching unit for enabling the operation of the actuator by the redundant operating system. system.

2. When the redundant operation system switching unit is effectively switched, the controller prohibits the actuator from being operated based on the signal from the electrical operation unit. The system according to claim 1.

3. When the redundant operating system switching unit is effectively switched, the controller sets the capacity of the pump that pumps the working fluid to a preset fixed capacity. The system according to claim 1.

4. The controller is set to a capacity that allows the actuator to operate at the minimum required speed. The system according to claim 3.

5. The circuit between the pump that pumps the working fluid and the control valve and the tank further includes a bleed valve that releases a portion of the working fluid pumped by the pump into the tank. When the redundant operating system switching unit is effectively switched, the controller sets the opening area of ​​the bleed valve so that the working fluid can be supplied from the pump at a pressure that enables the actuator to operate. The system according to claim 1.

6. When the redundant operation system switching unit is effectively switched, the controller restricts the maximum opening area of ​​the control valve so as not to open beyond a preset fixed opening area. The system according to claim 1.

7. When the redundant operating system switching unit is effectively switched, or when the controller that controls the control valve fails, the engine speed limit is restricted so that it is below a predetermined value. The system according to claim 1.

8. The engine speed is further provided with a throttle dial that can adjust the engine speed, When the redundant operation system switching unit is effectively switched, or when the controller that controls the control valve fails, the throttle dial is operated to set the engine speed to a speed below the upper limit. The system according to claim 7.

9. The aforementioned controller, Based on the signal from the electrical control unit, it is determined whether or not the electrical control unit is malfunctioning. The actuator assigned to the signal of the electrical control unit that has been determined to be in a malfunction state is forcibly stopped. When the redundant operation system switching unit is effectively switched, the actuator can be operated by the redundant operation system. The system according to claim 1.

10. When the redundant operating system switching unit is successfully switched, the controller notifies the operator that the redundant operating system switching unit has been successfully switched. The system according to claim 1.

11. A system for controlling working machinery, The vehicle of the aforementioned work machine is provided with left and right drive motors for moving the vehicle forward and backward, and for moving the left and right tracks of the vehicle in different directions. EPC valves for controlling the left and right travel motors, respectively, An electrical control unit for operating the left and right drive motors, Equipped with a controller, If the controller determines that there is an abnormality in the signal of the electrical control unit or the control signal of the EPC valve, it will stop both the left and right travel motors. system.

12. It is equipped with a redundant control system switching unit to enable actuator operation by a redundant control system, If the controller determines that there is an abnormality in either the signal of the electrical operation unit or the control signal of the EPC valve, and stops both the left and right travel motors, and then the redundant operation system switching unit is effectively switched, The controller allows the motor controlled by the signal that has been determined to be abnormal among the left and right travel motors to operate in the opposite direction to the direction in which the abnormality occurred. For motors controlled by signals that have not been identified as abnormal, operation in any direction is permitted. The system according to claim 11.

13. A system for controlling working machinery, An actuator for driving the aforementioned work machine, A control valve for operating the actuator, A controller that controls the control valve based on a signal from the electrical operating unit, A PPC lock setting unit for setting the shutoff and release of the pilot pressure source for operating the actuator, The system includes a PPC main pressure lock solenoid valve that shuts off and releases the main pressure of the pilot pressure based on a signal from the controller, The aforementioned controller, Determine whether the PPC lock setting unit is malfunctioning or not. If the PPC lock setting unit determines that a malfunction has occurred, it operates the PPC source pressure lock solenoid valve to the shut-off state and stops the output that controls the actuator. system.

14. It includes a redundant operating system switching unit for enabling the operation of the actuator by a redundant operating system, When the redundant operation system switching unit is effectively switched, the controller enables the control output of the actuator, which was stopped due to the PPC lock setting unit being determined to be in a faulty state, to be output again. The system according to claim 13.

15. Even when the redundant operation system switching unit is effectively switched, the controller does not release the PPC source pressure lock solenoid valve, which has been shut off due to the PPC lock setting unit being determined to be in a faulty state, from the shut-off state. The system according to claim 14.

16. The system further includes a PPC lock release unit that enables the release of the lock on the PPC main pressure lock solenoid valve even when the PPC lock setting unit is determined to be in a malfunction state. The PPC main pressure lock solenoid valve, which has been shut off due to the PPC lock setting unit being determined to be in a malfunction state, can be released from the shut-off state by activating the PPC lock release unit. The system according to claim 13.

17. A system for controlling working machinery, An actuator for driving the aforementioned work machine, A control valve for operating the actuator, A controller that controls the control valve based on a signal from the electrical operating unit, The system includes a setting input device for setting the signal assignment of the electrical operating unit corresponding to the actuator, The setting input device enables the assignment of a different operation input signal as the signal for operating the actuator in the event that the controller fails to recognize the operation input signals corresponding to one or more of the actuators. system.

18. It includes a redundant operating system switching unit for enabling the operation of the actuator by a redundant operating system, When the redundant operation system switching unit is effectively switched, the setting input device allows another operation input signal to be assigned as the signal for operating the actuator. The system according to claim 17.

19. It includes a redundant operating system switching unit for enabling the operation of the actuator by a redundant operating system, The aforementioned controller, Based on the signal from the electrical control unit, it is determined whether or not the electrical control unit is malfunctioning. The actuator assigned to the signal of the electrical control unit that has been determined to be in a malfunction state is forcibly stopped. When the redundant operation system switching unit is effectively switched, the setting input device allows another operation input signal to be assigned as the signal for operating the actuator. The system according to claim 17.

20. A display device that displays a screen for changing the signal assignment of the aforementioned electrical control unit, The system includes an authorization operation unit that permits changes to the signal assignment of the aforementioned electrical operation unit, When the authorization operation unit is operated to permit a change in the signal assignment of the electrical operation unit, the setting input device allows another operation input signal to be assigned as the signal for operating the actuator. The system according to claim 17.

21. A system for controlling working machinery, An actuator for driving the aforementioned work machine, A control valve for operating the actuator, A controller that controls the control valve based on a signal from the electrical operating unit, It includes a redundant operating system switching unit for enabling the operation of the actuator by a redundant operating system, The electrical control unit transmits to the controller a first operation signal in which the input amount detected according to the operation amount changes from a first value to a second value greater than the first value, and a second operation signal in the opposite direction to the first operation signal, which changes from the second value to the first value. If the redundant operation system switching unit is switched to the disabled state, the controller enables the control valve to be operated by either the first operation signal or the second operation signal of the electrical operation unit. When the redundant operation system switching unit is switched to an active state, the controller enables the control valve to be operated by a signal opposite to the signal used when the redundant operation system switching unit of the electrical operation unit was inactive. system.

22. The controller determines whether the electrical operating unit is malfunctioning, If the first operation signal of the electrical control unit is not of a normal value, the controller determines that the first operation signal of the electrical control unit is abnormal during the operation of the work machine, and forcibly stops the actuator operated by the first operation signal. When the redundant operation system switching unit is effectively switched, the controller enables the control valve to be operated by the second operation signal of the electrical operation unit. The system according to claim 21.

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