JP6438312B2 - Electric operating device of hydraulic work machine - Google Patents

Description

  The present invention relates to an electric operating device that controls driving of a hydraulic actuator mounted on a hydraulic working machine.

  There are a hydraulic operation device and an electric operation device as an operation device for controlling driving of a hydraulic actuator mounted on a conventional hydraulic excavator.

  In the hydraulic operating device, when the operator operates the operating lever, the output port of the pilot valve mechanically connected to the operating lever opens, and the pilot primary pressure led from the pilot pressure source to the input port is the operating amount of the operating lever. In response to this, the pressure is reduced and output as a pilot pressure. The pilot pressure strokes the main spool in the control valve. As a result, pressure oil is supplied from the hydraulic pump to the hydraulic actuator, and return oil from the hydraulic actuator is discharged to the tank.

  On the other hand, in an electric operation device equipped with an electric operation lever, the operation amount of the operation lever is converted into an electric signal and input to the controller, and the controller attaches a current corresponding to the operation amount to both ends of the main spool. The pilot pressure acting on the main spool is controlled by applying it to the electromagnetic proportional valve for guiding the pilot pressure to each of the pilot ports. In addition to the advantage that the hydraulic piping for transmitting the pilot pressure can be reduced, the electric operating device has the advantage of high compatibility with machine control and the like. As such an electric operation device, there are devices described in Patent Document 1 and Patent Document 2.

  In Patent Document 1, the degree of freedom of matching of each actuator that is combined and operated is increased by individually controlling the opening degrees of a plurality of main spools that control the flow of pressure oil to one actuator. A control device for improving the operability of a hydraulic construction machine is disclosed. In the hydraulic construction machine described in Patent Document 1, a proportional valve that supplies pilot pressure to pilot ports attached to both ends of individual main spools is provided, and the controller controls the operation amount of the electric operation lever, A control signal is obtained from a map showing the relationship between the operation amount of the expression control lever and the opening degree of each main spool, thereby controlling the proportional valve.

  Patent Document 2 discloses a construction machine that can prevent malfunction of a work device such as a boom when a failure occurs in an electric operation lever or a control unit. The construction machine described in Patent Document 2 includes a current drive unit that controls current so that a current value corresponding to an operation signal of the electric operation lever is applied to the electronic proportional valve. When the operation lock lever is operated in a state where a failure has occurred in the part, the current applied to the electronic proportional valve from the current driving part is cut off.

Japanese Patent Laid-Open No. 7-190009 JP 2010-286116 A

  However, in the control device for a hydraulic construction machine described in Patent Document 1, when any of the proportional valves for switching and driving the boom control valve fails, the boom control valve is not switched according to the boom lever operation, If the pressure oil is unintentionally supplied to the boom cylinder or the supply of pressure oil to the boom cylinder is unintentionally interrupted, the operability of the boom cylinder may be impaired. Similarly, if any of the proportional valves for switching the arm control valve fails, the operability of the arm cylinder may be impaired.

  On the other hand, in the construction machine provided with the electric operation lever described in Patent Document 2, when one of the two electronic proportional valves for switching and driving the electronic flow control valve fails, the lock lever is operated to When the drive current applied to the proportional valve is cut off, the operation of the hydraulic actuator stops and the operation of the hydraulic actuator becomes impossible. Alternatively, if the electronic proportional valve is stuck in a state where foreign matter is caught and the pilot pressure is applied to the main spool, the main spool can be operated even if the current applied to the electronic proportional valve is cut off by operating the lock lever. The pilot pressure continues to act on the hydraulic actuator, and the operation of the hydraulic actuator may not be stopped. In this case, the operation of the hydraulic actuator can be stopped by cutting off the pilot primary pressure introduced from the pilot pressure source, but the other hydraulic actuators cannot be operated.

  The present invention has been made in view of the above problems, and an object of the present invention is to switch a plurality of directional control valves that control the direction and flow rate of pressure oil supplied to a common hydraulic actuator. It is an object of the present invention to provide an electric operating device for a hydraulic working machine that can ensure the operability of a hydraulic actuator even if any of the devices fails.

  In order to solve the above-described problems, the present invention is mounted on a hydraulic working machine including a hydraulic pump device having at least one hydraulic pump and a hydraulic actuator driven by pressure oil supplied from the hydraulic pump device, In the electric operating device of the hydraulic working machine that controls the driving of the hydraulic actuator, an operating device that instructs a driving direction and a driving speed of the hydraulic actuator, and a first oil passage that connects the hydraulic pump device and the hydraulic actuator A first directional control valve for controlling the direction and flow rate of the pressure oil supplied to the hydraulic actuator via the first oil passage, the hydraulic pump device, and the hydraulic actuator. And a second spool provided in a second oil passage that connects to the hydraulic actuator via the second oil passage. A second directional control valve that controls the direction and flow rate of the supplied pressure oil, and first and second switching drives that output mutually opposing driving forces to the first spool in accordance with the operation of the operating device. A switching state of the first and second directional control valves, and a third and fourth switching drive devices that output driving forces that oppose each other to the second spool in response to an operation of the operating device. When it is determined that one of the first and second switching drive devices is in a failure state based on the detection result of the switching state detection device and the detection result of the switching state detection device, it relates to the operation of the operation device. The other switching drive device is controlled such that the first directional switching valve is held in the neutral position, and one of the third and fourth switching drive devices is controlled based on the detection result of the switching state detection device. It is determined that there is a fault condition. If the second directional control valve regardless of the operation of the operating device is intended to comprise a control device for controlling the other switching drive so as to be held in a neutral position.

  According to the present invention, even when one of the plurality of switching drive devices that switch the plurality of directional control valves that control the direction and flow rate of the pressure oil supplied to the common hydraulic actuator fails, the operation of the hydraulic actuator Can be secured.

1 is an external view of a hydraulic excavator as an example of a hydraulic working machine including an electric operation device according to a first embodiment of the present invention. It is a block diagram of the hydraulic drive device mounted in the hydraulic shovel shown in FIG. It is a block diagram of the electric operating device in the 1st Embodiment of this invention. It is a functional block diagram of the controller in the 1st Embodiment of this invention. It is a figure which shows the correspondence of the arm operation signal and each target pilot pressure in the 1st Embodiment of this invention. It is a flowchart which shows the failure determination process by the electromagnetic proportional valve failure determination part in the 1st Embodiment of this invention. It is a flowchart which shows the control processing by the main spool control part in the 1st Embodiment of this invention. It is a block diagram of the electric operating device in the 2nd Embodiment of this invention. It is a functional block diagram of the controller in the 2nd Embodiment of this invention. It is a flowchart which shows the failure determination process by the electromagnetic proportional valve failure determination part in the 2nd Embodiment of this invention. It is a block diagram of the electric operating device in the 3rd Embodiment of this invention. It is a block diagram of the electric operating device in the 4th Embodiment of this invention. It is a flowchart which shows the failure determination process by the electromagnetic proportional valve failure determination part in the 4th Embodiment of this invention. It is a flowchart which shows the control processing by the main spool control part in the 4th Embodiment of this invention. It is a block diagram of the electric operating device in the 5th Embodiment of this invention. It is a flowchart which shows the failure determination process by the electromagnetic proportional valve failure determination part in the 5th Embodiment of this invention.

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

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

  FIG. 1 is an external view of a hydraulic excavator as an example of a hydraulic working machine including an electric operation device according to the first embodiment. The hydraulic excavator includes a lower traveling body 11, an upper swing body 12, and a front work device 13.

  The lower traveling body 11 travels by driving a traveling right hydraulic motor (not shown) and a traveling left motor 3b.

  The upper swing body 12 is equipped with an engine 15, a hydraulic pump device 2, a swing hydraulic motor 4, a control valve 20, and the like. An operation device such as a travel right lever 1a, a travel left lever 1b, an operation right lever device 1c, and an operation left lever device 1d is provided in the cab 14 disposed on the left side in front of the upper swing body 12. The upper turning body 12 turns with respect to the lower traveling body 11 by driving the turning hydraulic motor 4. The control valve 20 distributes and supplies the oil discharged from the hydraulic pump device 2 to the hydraulic actuators 3a, 3b, 4, 5, 6, and 7 according to the operation of the operating devices 1a, 1b, 1c, and 1d. The hydraulic actuators 3a, 3b, 4, 5, 6, and 7 are driven.

  The front working device 13 includes a boom 8 that is attached to the upper swing body 12 so as to be rotatable in the vertical direction, an arm 9 that is rotatably attached to the tip of the boom 8, and a pivot that can be turned to the tip of the arm 9. And an attached bucket 10. The boom 8 is rotated in the vertical direction by the expansion and contraction of the boom cylinder 5, the arm 9 is rotated in the vertical and forward / backward directions by the expansion and contraction of the arm cylinder 6, and the bucket 10 is rotated in the vertical and longitudinal directions by the expansion and contraction of the bucket cylinder 7. To do.

  FIG. 2 is a configuration diagram of a hydraulic drive device mounted on the hydraulic excavator shown in FIG. In FIG. 2, the hydraulic drive device includes a hydraulic pump device 2, a plurality of hydraulic actuators 3a, 3b, 4-7, a control valve 20, a plurality of operation devices 1a, 1b, 1c, 1d, a controller 100, Electromagnetic proportional valves 43 to 54 are provided.

  The hydraulic pump device 2 includes first to third hydraulic pumps 2a, 2b, 2c and a pilot pump 2g. The first to third hydraulic pumps 2a, 2b, 2c and the pilot pump 2g are driven by the engine 15, and discharge the pressure oil to the first to third pump lines L1 to L3 (described later) and the pilot pump line L4, respectively. The first to third hydraulic pumps 2a, 2b, 2c are variable displacement hydraulic pumps, and their capacities can be adjusted by first to third regulators 2d, 2e, 2f, respectively. The discharge pressure of the pilot pump 2g is set to a predetermined pressure (hereinafter referred to as pilot primary pressure) P0 by a pilot relief valve 2h provided in the pilot pump line L4. The pilot primary pressure P0 is guided to the pilot valves 41 and 42 and the electromagnetic proportional valves 43 to 54 through the gate lock valve 30 provided in the pilot pump line L4. The gate lock valve 30 is switched by a lock lever 29.

  The control valve 20 is formed with first to third pump lines L1 to L3, and the first to third hydraulic pumps 2a, 2b, and 2c are connected to the first to third pump lines L1 to L3, respectively. ing. The first pump line L1 is provided with a traveling right direction switching valve 21, a bucket direction switching valve 22, and a boom first direction switching valve 23. By switching each of them, the first pump line L1 is moved to the right side. The hydraulic motor 3a communicates with the bucket cylinder 7 or the boom cylinder 5. The second pump line is provided with a turning direction switching valve 26, an arm second direction switching valve 25, and a traveling left direction switching valve 24. By switching each of these, the second pump line L2 is turned into a turning hydraulic motor. 4. It communicates with the arm cylinder 6 or the traveling left hydraulic motor 3b. The third pump line L3 is provided with a boom second direction switching valve 28 and an arm first direction switching valve 27. By switching each of them, the third pump line L3 is connected to the boom cylinder 5 or the arm cylinder 6. Communicate with.

  The electromagnetic proportional valves 43 to 54 reduce the pilot primary pressure P0 according to the drive current applied from the controller 100, and output the pilot primary pressure P0 as pilot pressures P5 to P16, respectively. The pilot pressures P5 and P6 are guided to the turning direction switching valve 26 to switch the turning direction switching valve 26. The pilot pressures P7 and P9 are guided to the boom first direction switching valve 23 to switch the boom first direction switching valve 23. The pilot pressures P8 and P10 are guided to the boom second direction switching valve 28 to switch the boom second direction switching valve 28. The pilot pressures P11 and P13 are guided to the arm first direction switching valve 27 to switch the arm first direction switching valve 27. The pilot pressures P12 and P14 are guided to the arm second direction switching valve 25 to switch the arm second direction switching valve 25. The pilot pressures P15 and P16 are guided to the bucket direction switching valve 22 to switch the bucket direction switching valve 22. The pilot pressures P7 to P14 are detected by pilot pressure sensors S3 to S10, respectively, and their detection signals are input to the controller 100.

  The traveling right pilot valve 41 mechanically connected to the traveling right lever 1a reduces the pilot primary pressure P0 according to the operation of the traveling right lever 1a, and outputs it as the traveling right forward pilot pressure P1 or the traveling right backward pilot pressure P2. To do. The pilot pressures P1 and P2 are guided to the traveling right direction switching valve 21 to switch the traveling right direction switching valve 21. Thereby, the first pump line L1 communicates with the traveling right hydraulic motor 3a, and the traveling right hydraulic motor 3a is driven by the pressure oil supplied from the first hydraulic pump 2a. The pilot pressures P1 and P2 are also guided to the shuttle valve 31 that selects the maximum pressure, and the maximum pressure (traveling right pilot pressure) selected by the shuttle valve 31 is detected by the traveling right pilot pressure sensor S1, The detection signal is input to the controller 100.

  The traveling left lever 1b mechanically connected to the traveling left pilot valve 42 reduces the pilot primary pressure P0 according to the operation of the traveling left lever 1b, and outputs it as traveling left forward pilot pressure P3 or traveling left backward pilot pressure P4. . The pilot pressures P3 and P4 are guided to the traveling left direction switching valve 24, and the traveling right direction switching valve 24 is switched. As a result, the third pump line L3 communicates with the traveling left hydraulic motor 3b, and the traveling left hydraulic motor 3b is driven by the pressure oil supplied from the third hydraulic pump 2a. The pilot pressures P3 and P4 are also led to the shuttle valve 32 that selects the maximum pressure, and the maximum pressure (traveling left pilot pressure) selected by the shuttle valve 31 is detected by the traveling left pilot pressure sensor S2. The detection signal is input to the controller 100.

  The operation right lever device 1c has an operation lever supported so as to be swingable in the front / rear and left / right directions, and outputs a boom operation signal and a bucket operation signal in accordance with the lever operation of the operation lever (hereinafter referred to as a boom operation signal). The lever operation to be generated is called a boom lever operation, and the lever operation to generate a bucket operation signal is called a bucket lever operation). The boom operation signal and the bucket operation signal are input to the controller 100.

  The operation left lever device 1d has an operation lever supported so as to be swingable in the front / rear / left / right direction, and outputs a turning operation signal and an arm operation signal in accordance with the lever operation of the operation lever (hereinafter referred to as a turning operation signal). The lever operation that is generated is called the turning lever operation, and the lever operation that generates the arm operation signal is called the arm lever operation). The boom operation signal and the bucket operation signal are input to the controller 100.

  Based on the operation signals input from the operation right lever device 1c and the operation left lever device 1d and the detection signals input from the sensors S1 to S10, the controller 100 controls the regulators 2d, 2e, 2f and the electromagnetic proportional valves 43 to. Control signals are output to 54 to control them. Further, when the controller 100 detects a failure of the electromagnetic proportional valves 45 to 52, the controller 100 outputs the failure information to the display device 60 to notify the operator.

  In FIG. 2, the direction switching valves 23 and 28, the electromagnetic proportional valves 45 to 48, the pilot pressure sensors S <b> 3 to S <b> 6, and the controller 100 related to the driving of the boom cylinder 5 are the electric type in the first embodiment applied to the boom cylinder 5. The direction switching valves 27 and 25, the electromagnetic proportional valves 49 to 52, the pilot pressure sensors S7 to S10, and the controller 100 that constitute the operating device and are related to the driving of the arm cylinder 6 are the same as those in the first embodiment applied to the arm cylinder 6. An electric operation device is configured. Hereinafter, the details of the electric operating device according to the first embodiment will be described.

  FIG. 3 is a configuration diagram of the electric operating device according to the first embodiment applied to the arm cylinder 6. In addition, since the structure of the electric operating device applied to the boom cylinder 5 is the same as that applied to the arm cylinder 6, the description thereof is omitted. In FIG. 3, the electric operating device 200 includes an arm first direction switching valve 27 and an arm second direction switching valve 25 for controlling the direction and flow rate of the pressure oil supplied to the arm cylinder 6, respectively, 25, solenoid proportional valves 49 to 52 as switching drive devices for switching operation, pilot pressure sensors S7 to S10 as switching state detection devices for detecting the switching state of the direction switching valves 27 and 25, and a controller 100 as a control device. And.

  The electromagnetic proportional valves 49 to 52 correspond to the pilot primary pressure P0 input from the pilot pressure source 40 including the pilot pump 2g and the pilot relief valve 2h shown in FIG. The pressure is reduced and output as pilot pressures P11 to P14.

  The pilot pressure P11 (hereinafter referred to as “arm first dump dumper” as appropriate) output from an electromagnetic proportional valve 49 (hereinafter referred to as “arm first dump solenoid proportional valve” as appropriate) is provided on both end faces of the spool 271 of the arm first direction switching valve 27. Pilot pressure ”) and a pilot pressure P13 (hereinafter referred to as“ arm first cloud pilot pressure ”as appropriate) output from an electromagnetic proportional valve 51 (hereinafter referred to as“ arm first cloud electromagnetic proportional valve ”as appropriate). The pilot pressure P12 (hereinafter referred to as “arm second dump dumping” as appropriate) output from the electromagnetic proportional valve 50 (hereinafter referred to as “arm second dump solenoid proportional valve” as appropriate) is provided on both end faces of the spool 251 of the arm second direction switching valve 25. Pilot pressure ”) and pilot pressure P14 (hereinafter referred to as“ arm second cloud pilot pressure ”as appropriate) output from the electromagnetic proportional valve 52 (hereinafter referred to as“ arm second cloud electromagnetic proportional valve ”as appropriate).

  When the arm cylinder 6 is driven in the reduction direction (dump direction), the arm first dump electromagnetic proportional valve 49 is driven to cause the arm first dump pilot pressure P11 to act on the right end surface of the spool 271 in the figure, and the third pump line L3 is communicated with the rod-side oil chamber of the arm cylinder 6, and the arm second dump pilot valve 50 is driven to cause the arm second dump pilot pressure P12 to act on the right end surface of the spool 251 as shown in FIG. The line L2 is communicated with the rod side oil chamber of the arm cylinder 6. As a result, the oil discharged from the second hydraulic pump 2b and the third hydraulic pump 2c merges and is supplied to the rod-side oil chamber of the arm cylinder 6, and the arm cylinder 6 is driven in the dump direction.

  On the other hand, when the arm cylinder 6 is driven in the extension direction (cloud direction), the arm first cloud electromagnetic proportional valve 51 is driven to cause the arm first cloud pilot pressure P13 to act on the left end surface of the spool 271 in the figure. 3 The pump line L3 is communicated with the bottom side oil chamber of the arm cylinder 6, and the arm second cloud pilot valve proportional valve 52 is driven to cause the arm second cloud pilot pressure P14 to act on the left end surface of the spool 251 in the figure, The second pump line L2 is communicated with the bottom side oil chamber of the arm cylinder 6. As a result, the oil discharged from the second hydraulic pump 2b and the third hydraulic pump 2c merges and is supplied to the bottom oil chamber of the arm cylinder 6, and the arm cylinder 6 is driven in the cloud direction.

  It is not always necessary to join the oil discharged from the two hydraulic pumps 2b and 2c and supply them to the arm cylinder 6. The spool 271 of the arm first direction switching valve 27 is held in the neutral position, and the third hydraulic pump 2c The supply of pressure oil to the arm cylinder 6 may be shut off and only the spool 251 of the arm second direction switching valve 25 may be switched to supply pressure oil only from the second hydraulic pump 2b. The spool 251 of the two-way switching valve 25 is held in the neutral position, the supply of pressure oil from the second hydraulic pump 2b to the arm cylinder 6 is shut off, and only the spool 271 of the arm first direction switching valve 27 is switched. The pressure oil may be supplied only from the third hydraulic pump 2c.

  FIG. 4 is a functional block diagram of the controller 100 according to the first embodiment. The controller 100 includes an electromagnetic proportional valve failure determination unit 120 and a main spool control unit 110.

  The electromagnetic proportional valve failure determination unit 120 includes a boom first lowering pilot pressure signal, a boom first raising pilot pressure signal, a boom second lowering pilot pressure signal, a boom second raising pilot pressure signal from the pilot pressure sensors S3 to S10, respectively. The arm first dump pilot pressure signal, the arm first cloud pilot pressure signal, the arm second dump pilot pressure signal, and the arm second cloud pilot pressure signal are input, and the boom operation is performed from the operation right lever device 1c and the operation left lever device 1d, respectively. A signal and an arm operation signal are input. The electromagnetic proportional valve failure determination unit 120 determines the failure state of the electromagnetic proportional valves 45 to 52 based on these input signals, and outputs the determination results to the main spool control unit 110.

  The main spool control unit 110 includes a boom operation signal and a bucket operation signal input from the operation right lever device 1c, an arm operation signal and a turning operation signal output from the operation left lever device 1d, and an electromagnetic proportional valve failure determination unit 120. On the basis of the determination result inputted from the first turn pilot pressure P5, the left turn pilot pressure P6, the first boom lowering pilot pressure P7, the first boom raising pilot pressure P9, the second lower pilot pilot pressure P8, the second boom pressure. Increased pilot pressure P10, arm first dump pilot pressure P11, arm first cloud pilot pressure P13, arm second dump pilot pressure P12, arm second cloud pilot pressure P14, bucket dump pilot pressure P15 and bucket cloud pilot pressure P16 Value (hereinafter referred to as target pilot pressure) It calculates the outputs control signals corresponding to these target pilot pressures (the drive current) to the electromagnetic proportional valve 43 to 54.

  Next, the correspondence between the arm operation signal and the target values of the pilot pressures P11 to P14 will be described with reference to FIG.

  FIG. 5A is a diagram showing a correspondence relationship between the arm operation signal and the target value of the arm first dump pilot pressure P11 (hereinafter, referred to as “arm first dump target pilot pressure” as appropriate) in the first embodiment. FIG. 5B is a diagram showing the relationship between the arm operation signal and the target value of the arm first cloud pilot pressure P13 (hereinafter, referred to as “arm first cloud target pilot pressure” as appropriate), and FIG. FIG. 5 is a diagram showing a relationship between an arm operation signal and a target value of an arm second dump pilot pressure P12 (hereinafter referred to as “arm second dump target pilot pressure” as appropriate), and FIG. It is a figure which shows the relationship with the target value (henceforth "arm 2nd cloud target pilot pressure" suitably) of arm 2nd cloud pilot pressure P14.

  5 (a) to 5 (d), solid line portions Ma1, Mb1, Mc1, and Md1 correspond to the case where the oil discharged from the two hydraulic pumps 2b and 2c is merged and supplied to the arm cylinder 6 (hereinafter referred to as “appropriately” Compound pilot pressure map). 5A and 5B, the broken line portions Ma2 and Mb2 switch the arm first direction switching valve 27 in a state where the arm second direction switching valve 25 is held at the neutral position, and the hydraulic pump 2b FIG. 5 (c) and FIG. 5 (d) are correspondences when only the discharge oil is supplied to the arm cylinder 6 (hereinafter referred to as “arm first single pilot pressure map” or “single pilot pressure map” as appropriate). Broken line portions Mc2 and Md2 indicate the case where the arm first direction switching valve 25 is switched while the arm first direction switching valve 27 is held in the neutral position, and only the oil discharged from the hydraulic pump 2c is supplied to the arm cylinder 6. Correspondence (hereinafter referred to as “arm second single pilot pressure map” or “single pilot pressure map” as appropriate). As shown in FIGS. 5A to 5D, the target pilots in the arm first single pilot pressure maps Ma2 and Mb2 and the arm second single pilot pressure maps Mc2 and Md2 are combined into the composite pilot pressure maps Ma1, Mb1, By setting both of the direction switching valves 27 and 25 to be higher than those in Mc1 and Md1, the direction switching valves 27 and 25 are switched from the state in which the discharge oil from the two hydraulic pumps 2b and 2c is supplied to the arm cylinder 6. 25, when only one of the hydraulic pumps 2b and 2c is switched to a state where only the discharge oil is supplied to the arm cylinder 6, the supply flow rate to the arm cylinder 6 decreases, that is, the arm A decrease in the speed of the cylinder 6 can be suppressed.

  FIG. 6 is a flowchart showing a failure determination process performed by the electromagnetic proportional valve failure determination unit 120 in the first embodiment. In FIG. 6, only the failure determination process for the arm first dump electromagnetic proportional valve 49 is illustrated, but the electromagnetic proportional valve failure determination unit 120 includes the arm first cloud electromagnetic proportional valve 51 and the arm second dump electromagnetic. The same failure determination process is performed for the proportional valve 50 and the arm second cloud electromagnetic proportional valve 52. Hereinafter, each step constituting the flow of FIG. 6 will be described in order.

  In step S1201, the electromagnetic proportional valve failure determination unit 120 refers to the pilot pressure map Ma1 or Ma2 of the arm first dump, and calculates the arm first dump target pilot pressure corresponding to the arm operation signal. In subsequent step S1202, a pressure difference between the arm first dump pilot pressure P11 input from the pilot pressure sensor S7 and the arm first dump target pilot pressure is calculated. In subsequent step S1210, it is determined whether or not the pressure difference is within an allowable range (threshold value ΔP or less).

  If YES in step S1210 (the pressure difference is equal to or less than the threshold ΔP), a flag indicating a failure state of the arm first dump solenoid proportional valve 49 (hereinafter referred to as “arm first dump failure flag”) is normal in step S1211. A flag value (hereinafter referred to as “normal”) indicating the state is set. On the other hand, if NO is determined in step S1210 (the pressure difference is larger than the threshold ΔP), whether or not the arm first dump pilot pressure P11 is equal to or lower than the minimum pilot pressure Pmin that can drive the arm cylinder 6 in step S1220. Determine.

  If YES in step S1220 (arm first dump pilot pressure P11 ≦ Pmin), in step S1221, a flag value indicating that the pilot pressure cannot be output to the arm first dump failure flag (hereinafter referred to as “close failure”). ”). On the other hand, if NO (arm first dump pilot pressure P11> Pmin) is determined in step S1220, a flag indicating a failure state in which an unintended pilot pressure is output to the arm first dump failure flag in step S1222. In step S1223, the arm first dump pilot pressure P11 is set as the arm first cloud target pilot pressure, and in step S1224, the arm first cloud target pilot is set. The pressure is output to the main spool control unit 110.

  Subsequent to steps S1211, S1221, and S1224, the arm first dump failure flag is output to the main spool control unit 110 in step S1230.

  FIG. 7 is a flowchart showing a control process by the main spool control unit 110 in the first embodiment. In FIG. 7, only the control processing for the electromagnetic proportional valves 49 and 51 for switching and driving the arm first direction switching valve 27 is illustrated, but the main spool control unit 110 controls the arm second direction switching valve 25. The same control process is performed for the electromagnetic proportional valves 50 and 52 that are switched. Hereinafter, each step constituting the flow of FIG. 7 will be described in order.

  In step S1100, the main spool control unit 110 determines whether or not both the arm first dump failure flag and the arm first cloud failure flag input from the electromagnetic proportional valve failure determination unit 120 are “normal”.

  If YES in step S1100 (both the arm first dump failure flag and the arm first cloud failure flag are “normal”), in step S1110, both the arm second cloud failure flag and the arm second dump failure flag are displayed. It is determined whether or not it is “normal”. When it is determined NO in step S1110 (the arm first dump failure flag or the arm first cloud failure flag is not “normal”), in step S1111 the pilot pressure map of the arm first dump and the pilot of the arm first cloud The pressure map is switched from the maps Ma1 and Mb1 when the arm is second normal to the maps Ma2 and Mb2 when the arm is second failure. If YES in step S1110 (both the arm second cloud failure flag and the arm second dump failure flag are both “normal”), or following step S1111, in step S1112, the pilot pressure map of the arm first dump The arm first dump target pilot pressure and the arm first cloud target pilot pressure corresponding to the arm operation signal are calculated with reference to Ma1 / Ma2 and the pilot pressure map Mb1 / Mb2 of the arm first cloud.

  If it is determined NO in step S1100 (the arm first dump failure flag or the arm first cloud failure flag is not “normal”), in step S1120, the arm first dump failure flag or the arm first cloud failure flag is “ It is determined whether or not it is a “close failure”. If YES in step S1120 (the arm first dump failure flag or the arm first cloud failure flag is “close failure”), in step S1121, the pilot is set to the arm first dump target pilot pressure and the arm first cloud target pilot pressure. Set the control pressure when the hydraulic pressure is shut off.

  Subsequent to steps S1112, S1121, or when it is determined NO in step S1120 (the arm first dump failure flag or the arm first cloud failure flag is “open failure”), in step S1130, the arm first dump target pilot The drive current corresponding to the pressure and the arm first cloud target pilot pressure is output to the electromagnetic proportional valves 49 and 51, respectively.

  According to the first embodiment configured as described above, when one of the electromagnetic proportional valves 49 to 52 is in a failure state in which pilot pressure cannot be output due to sticking or disconnection, this failure occurs regardless of the arm lever operation. By shutting off the pilot pressure output from the solenoid proportional valve opposed to the solenoid proportional valve and the spool 271 or 251, the spool is held in the neutral position, and only the other spool 251 or 271 is operated by the arm lever. Switching operation is performed according to the above.

  On the other hand, when one of the electromagnetic proportional valves 49 to 52 enters a failure state in which an unintended pilot pressure is output due to sticking or short-circuiting, the electromagnetic proportional valve and the spool 271 or 251 in this failure state regardless of the arm lever operation. The spool is held in the neutral position by controlling the proportional solenoid valve that is opposed to the pilot pressure to the same level as the pilot pressure that is output from the failed proportional solenoid valve. Only one of the spools is switched according to the arm lever operation.

  In this way, even when one of the electromagnetic proportional valves 49 to 52 fails, the supply of the pressure oil to the arm cylinder 6 via the direction switching valve 27 or 25 that cannot be switched according to the arm lever operation is cut off. The operability of the arm cylinder 6 can be ensured by supplying pressure oil to the arm cylinder 6 only through the other direction switching valve 25 or 27 that can be switched according to the arm lever operation. Similarly, the operability of the boom cylinder 5 can be ensured even when one of the electromagnetic proportional valves 45 to 48 fails.

  Further, the correspondence relationship between the arm operation signal and each target pilot pressure is defined even when one of the electromagnetic proportional valves 49 to 52 is in a failure state and one of the direction switching valves 27 or 25 is held at the neutral position. By switching the pilot pressure map to be performed from the composite pilot pressure map to the single pilot pressure map and setting the target pilot pressure with respect to the arm operation signal high, it is possible to suppress a decrease in the speed of the arm cylinder 6. Similarly, the speed reduction of the boom cylinder 5 can be suppressed while any of the electromagnetic proportional valves 45 to 48 is in a failure state and one of the direction switching valves 23 or 28 is held at the neutral position.

  A second embodiment of the present invention will be described with reference to FIGS. 8 to 10, the same components as those in FIGS. 1 to 7 are denoted by the same reference numerals, and the description thereof is omitted. The main difference when the second embodiment is compared with the first embodiment is that, in the first embodiment, the failure state of the electromagnetic proportional valves 49 to 52 is determined using the pilot pressure sensors S7 to S10. On the other hand, in the second embodiment, the determination is made by using spool stroke sensors S27 and S25 attached to the spools 271 and 251 of the direction control valves 27 and 25, respectively.

  FIG. 8 is a configuration diagram of the electric operating device according to the second embodiment applied to the arm cylinder 6. In FIG. 8, the electric operating device 200b includes a spool stroke sensor S27 attached to the spool 271 of the arm first direction switching valve 27, and a spool stroke sensor S25 attached to the spool 251 of the arm first direction switching valve 25. The spool stroke signal detected by the spool stroke sensors S27 and S25 is input to the controller 100. The spool stroke sensors S27 and S25 constitute a switching state detection device that detects the switching state of the direction switching valves 27 and 25.

  FIG. 9 is a functional block diagram of the controller 100 according to the second embodiment. The electromagnetic proportional valve failure determination unit 120 is attached to the boom first spool stroke signal detected by the spool stroke sensor S23 attached to the spool of the boom first direction switching valve 23 and the spool of the boom second direction switching valve 28. The boom second spool stroke signal detected by the spool stroke sensor S28, the arm first spool stroke signal detected by the spool stroke sensor S27b attached to the spool 271 of the arm first direction switching valve 27, and the arm second direction switching. An arm second spool stroke signal detected by a spool stroke sensor S25 attached to the spool 251 of the valve 25 is input. The electromagnetic proportional valve failure determination unit 120 determines the failure state of the electromagnetic proportional valves 45 to 52 based on these input signals, and outputs the determination results to the main spool control unit 110.

  FIG. 10 is a flowchart showing a failure determination process performed by the electromagnetic proportional valve failure determination unit 120 in the second embodiment. In step S1201b, the electromagnetic proportional valve failure determination unit 120 calculates the arm first spool target opening from the arm operation signal. In subsequent step S1202b, an area difference between the arm first spool target opening and the arm first spool opening is calculated. In subsequent step S1210b, it is determined whether or not the area difference is within an allowable error range (threshold value ΔA or less).

  If it is determined in step S1210b that YES (the area difference is equal to or less than the allowable error ΔA), the processing from step S1211 is executed. On the other hand, if it is determined NO in step S1210b (the area difference is larger than the allowable error ΔA), it is determined in step S1220b whether the arm first spool opening is equal to or smaller than the minimum opening Amin that can drive the direction switching valve 27. judge.

  If it is determined as YES in step S1220b (the arm first spool opening is equal to or smaller than the minimum opening Amin), the processes after step S1221 are executed. On the other hand, if it is determined NO in step S1220b (the arm first spool opening is larger than the minimum opening Amin), the processes after step S1232 are executed.

  Also in the second embodiment configured as described above, the same effects as in the first embodiment can be obtained. Furthermore, the electric operating device (FIG. 3) in the first embodiment uses the four pilot pressure sensors S7 to S10 to determine the failure state of the electromagnetic proportional valves 49 to 52, whereas in the second embodiment. Since the electric operating device (FIG. 8) determines the failure state using the two spool stroke sensors S27 and S25, the configuration is simpler than that of the first embodiment.

  A third embodiment of the present invention will be described with reference to FIG. FIG. 11 is a configuration diagram of an electric operating device according to the third embodiment applied to the arm cylinder 6. In FIG. 11, the same components as those in FIGS. 1 to 10 are denoted by the same reference numerals, and the description thereof is omitted. The main difference when the third embodiment is compared with the second embodiment is that, in the second embodiment, a pilot hydraulic direction switching valve is used as the arm first direction switching valve and the arm second direction switching valve. 27 and 25 are used, but in the third embodiment, electromagnetic direction switching valves 27b and 25b are used.

  In FIG. 11, solenoids 49b and 51b as switching drive devices are respectively attached to both end surfaces of the spool 271 included in the arm first direction switching valve 27b. The solenoid 49 b causes a force proportional to the drive current applied from the controller 100 to act from the right side of the spool 271 in the figure, and causes the third pump line L 3 to communicate with the rod side oil chamber of the arm cylinder 6. On the other hand, the solenoid 51 b causes a force proportional to the drive current applied from the controller 100 to act from the left side of the spool 271 in the figure, and causes the third pump line L 3 to communicate with the bottom side oil chamber of the arm cylinder 6.

  Solenoids 50b and 52b as switching drive devices are attached to both end surfaces of the spool 251 of the arm second direction switching valve 25, respectively. The solenoid 50 b causes a force proportional to the current applied from the controller 100 to act from the right side of the spool 251, and causes the second pump line L 2 to communicate with the rod side oil chamber of the arm cylinder 6. On the other hand, the solenoid 52 b causes a force proportional to the drive current applied from the controller 100 to act from the left side of the spool 251 in the drawing so that the second pump line L 2 communicates with the bottom side oil chamber of the arm cylinder 6.

  The failure determination processing of the electromagnetic proportional valve failure determination unit 120 in the third embodiment is the same as the failure determination processing except that the processing related to the pilot pressure in FIG. 2 (steps S1222b, S1223, and S1224) is replaced with processing related to the solenoid drive current. This is the same as the second embodiment.

  According to the third embodiment configured as described above, when one of the solenoids 49b, 50b, 51b, 52b becomes a failure state in which a driving force cannot be output to the spool 271 or 251 due to disconnection or the like, the arm lever is operated. Regardless of this, the spool 271 or 251 is held in the neutral position by controlling the solenoid that is opposed to the failed solenoid to the spool 271 or 251 so that the driving force is not output to the spool, and the other spool 251 or 251 Only 271 is switched according to the arm lever operation.

  Further, when any of the solenoids 49b, 50b, 51b, 52b becomes uncontrollable due to a short circuit or the like outputting a driving force that does not correspond to the arm lever operation to the spool 271 or 251, the arm lever Regardless of the operation, the spool 271 or 251 is placed in the neutral position by driving the solenoid that opposes the failed solenoid and the spool 271 or 251 and applying the same force to the spool 271 or 251 as the failed solenoid. Only the other spool 251 or 271 is switched according to the arm lever operation.

  As a result, even when one of the solenoids 49b, 50b, 51b, 52b fails, one spool 271 or 251 that cannot be switched according to the arm lever operation is held in the neutral position, and this one spool 271 or The direction switching valve 25 having the other spool 251 or 271 that can stop the supply of pressure oil to the arm cylinder 6 via the direction switching valve 27 or 25 having 251 and can be switched according to the arm lever operation. By supplying pressure oil to the arm cylinder 6 via only 27, the operability of the arm cylinder 6 can be ensured.

  A fourth embodiment of the present invention will be described with reference to FIGS. 12-14, the same code | symbol is attached | subjected to the same component as FIGS. 1-11, and description for the second time is abbreviate | omitted. The difference between the fourth embodiment and the first embodiment is that, in the first embodiment, the pilot pressure sensors S7 to S10 are used to determine the failure of the electromagnetic proportional valves 49 to 52, whereas In the fourth embodiment, a failure determination is performed using a cylinder stroke sensor S60 attached to the arm cylinder 6.

  FIG. 12 is a configuration diagram of an electric operating device according to the fourth embodiment applied to the arm cylinder 6. In FIG. 12, the electric operating device 200 d includes a cylinder stroke sensor S <b> 60 attached to the arm cylinder 6, and an arm cylinder stroke signal detected by the cylinder stroke sensor S <b> 60 is input to the controller 100. The cylinder stroke sensor S60 constitutes a switching state detection device that detects the switching state of the direction switching valves 27 and 25.

  FIG. 13 is a flowchart showing a failure determination process performed by the electromagnetic proportional valve failure determination unit 120 in the fourth embodiment. Hereinafter, each step constituting the flow of FIG. 13 will be described in order.

  In step S1201d, the electromagnetic proportional valve failure determination unit 120 calculates the target speed of the arm cylinder 6 from the arm operation signal input from the operation left lever device 1d. In subsequent step S1202d, the operating speed of the arm cylinder 6 is calculated based on the arm cylinder stroke signal input from the arm cylinder stroke sensor S60. In a succeeding step S1210d, it is determined whether or not there is an arm lever operation.

  If it is determined YES in step S1210d (no arm lever operation), it is determined in step S1220d whether the operating direction of the arm cylinder 6 is the cloud side based on the operating speed of the arm cylinder 6. If YES (cloud operation) is determined in step S1220d, “open failure” is set in the arm cloud failure flag in step S1221d. On the other hand, if NO (non-cloud operation) is determined in step S1220d, it is determined in step S1230d based on the operation speed of the arm cylinder 6 whether the operation direction of the arm cylinder 6 is the dump side. If YES (dump side) is determined in step S1230d, “open failure” is set in the arm dump failure flag in step S1231d.

  On the other hand, if it is determined NO (with arm lever operation) in step S1210d, it is determined in step S1240d whether the operation direction is the cloud side based on the arm operation signal.

  If YES (cloud side) is determined in step S1240d, it is determined in step S1250d whether the operating speed of the arm cylinder 6 is lower than the target speed calculated in step S1201. If it is determined YES in step S1250d (the operation speed is lower than the target speed), “close failure” is set in the arm cloud failure flag in step S1251d.

  If NO (dump operation) is determined in step S1240d, it is determined in step S1260d whether the operating speed of the arm cylinder 6 is lower than the target speed calculated in step S1201. If it is determined YES in step S1260d (the operation speed is lower than the target speed), “close failure” is set in the arm dump failure flag in step S1261d.

  Subsequent to steps S1221d, S1231d, S1251d, and S1261 or when it is determined NO in the determination processing of steps S1230d, S1250d, and S1260d, the main spool control unit 110 sets the arm dump failure flag and the arm cloud failure flag in step S1270d. Output to.

  FIG. 14 is a flowchart illustrating a control process performed by the main spool control unit 110 according to the fourth embodiment. Hereinafter, each step which comprises the flow of FIG. 14 is demonstrated in order.

  In step S1100d, the main spool control unit 110 determines whether there is an arm lever operation. If it is determined YES in step S1100d (with arm lever operation), in step S1101d, the arm first pilot pressure map Ma1, Mb1 or Ma2, Mb2 and the arm second pilot pressure map Mc1, Md2 or Mc2, Md2 ( Referring to FIG. 5), the target pilot pressure corresponding to the arm operation signal is calculated. In subsequent step S1102d, a drive current corresponding to each target pilot pressure is calculated.

  If NO (no arm lever operation) is determined in step S1100d, it is determined in step S1110d whether “open failure” is set in the arm cloud failure flag or the arm dump failure flag. If it is determined as YES (open failure is set) in step S1110d, it is determined in step S1120d whether “closed failure” is set in the arm dump failure flag. If it is determined YES in step S1120d (the open failure is set in the arm dump failure flag), the drive current of the electromagnetic proportional valve 51 or 52 is increased in step S1121d. In a succeeding step S1122d, it is determined whether or not the arm dumping operation is stopped. If it is determined as YES (arm dump operation stop) in step S1122d, the driving current of the cloud electromagnetic proportional valve 51 or 52 at this time is set to the driving current at the time of failure of the cloud electromagnetic proportional valve 51 or 52. On the other hand, if it is determined as NO (arm dump operation is continuing) in step S1122d, the process returns to step S1121d. By repeating the processing of steps S1121 and S1122, the pilot pressure output from the electromagnetic proportional valve 49 or 50 that has caused the open failure cancels out the pilot pressure output from the opposing electromagnetic proportional valve 51 or 52, and an open failure occurs. The direction switching valve 27 or 25 that is driven to switch by the electromagnetic proportional valve 49 or 50 that has caused the is held in the neutral position.

  When it is determined NO in step S1120d (cloud open failure is set), the drive current of the electromagnetic proportional valve 49 or 50 is increased in step S1124d. In a succeeding step S1125d, it is determined whether or not the arm cloud operation is stopped. If it is determined as YES (arm cloud operation stop) in step S1125d, the drive current of the dump electromagnetic proportional valve 49 or 50 at this time is set to the drive current at the time of failure of the electromagnetic proportional valve 49 or 50. If it is determined as NO (while arm cloud operation is continuing) in step S1125d, the process returns to step S1124d. By repeating the processing of steps S1124 and S1125, the pilot pressure output from the electromagnetic proportional valve 51 or 52 that has caused the open failure cancels out the pilot pressure output from the opposing electromagnetic proportional valve 49 or 50, and an open failure occurs. The direction switching valve 27 or 25, which is driven to switch by the electromagnetic proportional valve 51 or 52 that has been raised, is held in the neutral position.

  If it is determined NO in step S1110d (arm open failure is not set), it is determined in step S1130d whether “closed failure” is set in the arm cloud failure flag or the arm dump failure flag. If it is determined YES in step S1130d ("closed failure" is set), an electromagnetic proportional valve of "closed failure" is specified in step S1131d. Specifically, when the driving current is individually applied to the electromagnetic proportional valves 49 to 52 while monitoring the operation of the arm cylinder 6, and the arm cylinder 6 does not operate despite the driving current being applied, The electromagnetic proportional valve is identified as a “closed failure” electromagnetic proportional valve. Subsequent to step S1131d, in step S1132d, the drive current at the time of pilot pressure cutoff of the electromagnetic proportional valve facing the “closed failure” electromagnetic proportional valve is set to the drive current at the time of failure. If it is determined NO in step S1130d (no “closed failure” is set), the processing after step S1101d is executed.

  Subsequent to steps S1123d, S1126d, and S1132d, in step S1140d, one of the operable pilot pressure maps of the arm first direction switching valve 27 and the arm second direction switching valve 25 is converted into the combined pilot pressure map Ma1, Mb1 or Mc1. , Md1 to the single pilot pressure map Ma2, Mb2 or Mc2, Md2.

  Subsequent to steps S1102d and S1140d, in step S1150d, it is determined whether or not there is a drive current setting at the time of failure. If YES in step S1150d (failure drive current is set), in step S1151d, any of the drive currents calculated in step S1102d is replaced with the drive current in failure set in steps S1123, S1126, or S1132. Update with.

  Subsequent to step S1151d or when it is determined NO (no drive current at the time of failure) in step S1150d, each drive current is output to the electromagnetic proportional valves 49 to 52 in step S1160d.

  Also in the fourth embodiment configured as described above, the same effect as in the first embodiment can be achieved. Furthermore, the electric operating device 200 (FIG. 3) in the first embodiment performs failure determination of the electromagnetic proportional valves 49 to 52 using the four pilot pressure sensors S7 to S10, whereas in the fourth embodiment. Since the electric operation device 200d (FIG. 12) performs failure determination of the electromagnetic proportional valves 49 to 52 using one cylinder stroke sensor S60, the configuration is simpler than that of the first embodiment.

  A fifth embodiment of the present invention will be described with reference to FIGS. 15 and 16. 15 and 16, the same components as those in FIGS. 1 to 14 are denoted by the same reference numerals, and the description thereof is omitted. The difference when the fifth embodiment is compared with the fourth embodiment is that in the fourth embodiment, a failure of the electromagnetic proportional valves 49 to 52 is detected using the cylinder stroke sensor S60 attached to the arm cylinder 6. In contrast, in the fifth embodiment, the pressure sensor S61 attached to the pressure oil conduit communicating with the bottom oil chamber of the arm cylinder 6 and the pressure oil conduit communicating with the rod oil chamber of the arm cylinder 6 are determined. It is a point which determines the failure of the electromagnetic proportional valves 49-52 using the pressure sensor S62 attached to.

  FIG. 15 is a configuration diagram of an electric operating device according to the fifth embodiment applied to the arm cylinder 6. The electric operating device 200e includes a pressure sensor S61 attached to the pressure oil conduit communicating with the bottom side oil chamber of the arm cylinder 6 and a pressure sensor attached to the pressure oil conduit communicating with the rod side oil chamber of the arm cylinder 6. The bottom pressure signal and the rod pressure signal detected by the pressure sensors S61 and S62 are input to the controller 100. The pressure sensors S61 and S62 constitute a switching state detection device that detects the switching state of the direction switching valves 27 and 25.

  FIG. 16 is a flowchart showing a failure determination process performed by the electromagnetic proportional valve failure determination unit 120 in the fifth embodiment. The difference between the fifth embodiment and the fourth embodiment is that, in the fourth embodiment (FIG. 13), the arm operating speed is calculated from the arm cylinder stroke signal in step S1202d. In the fifth embodiment, the arm operating speed is estimated from the pressure difference between the bottom pressure and the rod pressure in step S1202e.

  Also in the fifth embodiment configured as described above, the same effect as in the first embodiment can be achieved. Furthermore, the electric operating device 200 (FIG. 3) in the first embodiment performs failure determination of the electromagnetic proportional valves 49 to 52 using the four pilot pressure sensors S7 to S10, whereas in the fifth embodiment. The electric operation device 200e (FIG. 15) uses the two pressure sensors S61 and S62 to perform failure determination of the electromagnetic proportional valves 49 to 52, and thus the configuration is simpler than that of the first embodiment.

  In addition, this invention is not limited to above-described embodiment, Various modifications are included. For example, in the above-described embodiment, an example in which the present invention is applied to the boom cylinder 5 and the arm cylinder 6 has been described. However, any hydraulic actuator configured to supply pressure oil via a plurality of directional control valves may be used. However, the present invention is not limited to these. In the above-described embodiment, the example in which the present invention is applied to the configuration in which the discharge oil of the two hydraulic pumps 2b and 2c is supplied to the common hydraulic actuator 6 via the direction switching valves 27 and 25, respectively, has been described. The present invention is also applicable to a configuration in which the discharge oil of a single hydraulic pump is divided and supplied to a common hydraulic actuator via two directional control valves.

  Further, the above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to the one having all the configurations described. Further, a part of the configuration of an embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of an embodiment. Moreover, it is possible to add / delete / replace other configurations for a part of the configurations of the embodiments.

1c: Operation right lever device (operation device), 1d: Operation left lever device (operation device), 2a, 2b, 2c ... Hydraulic pump, 5 ... Boom cylinder (hydraulic actuator), 6 ... Arm cylinder (hydraulic actuator), 23 , 28 ... Direction switching valve (first and second direction switching valve), 25, 27 ... Direction switching valve (first and second direction switching valve), 25b, 27b ... Direction switching valve (first and second direction switching valve) Valve), 40 ... pilot pressure source, 45-48 ... electromagnetic proportional valve (first to fourth switching drive device), 49-52 ... electromagnetic proportional valve (first to fourth switching drive device), 49b, 50b, 51b , 52b ... Solenoid (first to fourth switching drive devices), 100 ... Controller (control device), 200, 200b, 200c, 200d, 200e ... Electric operation device, 251, 271 ... Spool, P0 ... Lot primary pressure, P7 to P14 ... pilot pressure (driving force), S3 to S6 ... pilot pressure sensor (switching state detection device), S7 to S10 ... pilot pressure sensor (switching state detection device), S61, S62 ... pressure sensor ( Switching state detection device), S23, S25, S27, S28 ... spool stroke sensor (switching state detection device), S60 ... cylinder stroke sensor (switching state detection device)

Claims (9)

The hydraulic working machine is mounted on a hydraulic working machine having a hydraulic pump device having at least one hydraulic pump and a hydraulic actuator driven by pressure oil supplied from the hydraulic pump device, and controls driving of the hydraulic actuator. In an electric operating device,
An operating device for instructing a driving direction and a driving speed of the hydraulic actuator;
A first spool provided in a first oil passage connecting the hydraulic pump device and the hydraulic actuator, and controlling a direction and a flow rate of pressure oil supplied to the hydraulic actuator via the first oil passage; A first directional control valve that
A second spool provided in a second oil passage connecting the hydraulic pump device and the hydraulic actuator, and controlling a direction and a flow rate of the pressure oil supplied to the hydraulic actuator via the second oil passage; A second directional control valve that
First and second switching drive devices that output driving forces that oppose each other to the first spool in response to an operation of the operation device;
A third and a fourth switching drive device for outputting a driving force opposed to each other with respect to the second spool in response to an operation of the operation device;
A switching state detection device for detecting a switching state of the first and second directional control valves;
When it is determined that one of the first and second switching drive devices is in a failure state based on the detection result of the switching state detection device, the first directional control valve is operated regardless of the operation of the operation device. When the other switching drive device is controlled to be held in the neutral position and it is determined that one of the third and fourth switching drive devices is in a failure state based on the detection result of the switching state detection device Comprises a control device for controlling the other switching drive device so that the second direction switching valve is held in a neutral position regardless of the operation of the operation device. Operating device. In the electric operating device of the hydraulic working machine according to claim 1,
Wherein the controller determines that there is a fault condition or the hand can not output the driving force to the first spool of the switching state detecting apparatus for detecting that said first and second switching drive unit on the basis of the In this case, the other switching drive device is controlled so as not to output a driving force to the first spool, and one of the third and fourth switching drive devices is based on the detection result of the switching state detection device. If it is determined that the driver is in a failure state where the driving force cannot be output to the second spool, the other switching drive device is controlled so as not to output the driving force to the second spool. Electric operating device for hydraulic working machines. In the electric operating device of the hydraulic working machine according to claim 1,
The controller outputs a driving force that does not correspond to the operation of the operating device hand either detection result of the first and second switching drive unit on the basis of the relative said first spool of the switching state detecting device The other switching drive device is controlled to output the same level of driving force to the first spool, and based on the detection result of the switching state detection device, 3 and if the hand or of the fourth switching drive unit is determined to be in the failure state of outputting a driving force that does not correspond to the operation of the operating device with respect to the second spool, relative to the second spool An electric operating device for a hydraulic working machine, wherein the other switching drive device is controlled to output an equivalent driving force. In the electric operating device of the hydraulic working machine according to claim 1,
When the control device determines that one of the first and second switching drive devices is in a failure state based on the detection result of the switching state detection device, the control device corresponds to the operation of the operation device. 2 to increase the driving force in the direction changeover valve, when said hand any one of the third and fourth switching drive unit based on a detection result of the switching state detecting device is judged to be in a fault condition, the operation An electric operating device for a hydraulic working machine, wherein a driving force to the first directional control valve corresponding to the operation of the device is increased. In the electric operating device of the hydraulic working machine according to any one of claims 1 to 4,
The hydraulic working machine further includes a pilot pressure source,
Each of the first and second directional control valves is a hydraulic pilot type directional control valve,
The first to fourth switching drive devices are first to fourth electromagnetic proportional valves that respectively reduce the pilot primary pressure input from the pilot pressure source in accordance with the operation amount of the operating device and output the pilot pressure. Yes,
The switching state detection device includes first to fourth pressure sensors that respectively detect pilot pressures output from the first to fourth electromagnetic proportional valves. In the electric operating device of the hydraulic working machine according to any one of claims 1 to 4,
The first and second directional control valves are electromagnetic directional control valves, respectively.
The electric operating device for a hydraulic working machine, wherein the first to fourth switching drive devices are first to fourth solenoids that output a driving force proportional to an applied driving current. In the electric operating device of the hydraulic working machine according to any one of claims 1 to 4,
The switching state detecting device includes a stroke sensor attached to the first spool and a stroke sensor attached to the second spool. In the electric operating device of the hydraulic working machine according to any one of claims 1 to 4,
The hydraulic actuator is a hydraulic cylinder;
The switch operating state detecting device includes a stroke sensor attached to the hydraulic cylinder. In the electric operating device of the hydraulic working machine according to any one of claims 1 to 4,
The hydraulic actuator is a hydraulic cylinder;
The switching state detection device includes a fifth pressure sensor that detects a pressure in a bottom side oil chamber of the hydraulic cylinder, and a sixth pressure sensor that detects a pressure in a rod side oil chamber of the hydraulic cylinder. Electric operating device for hydraulic working machines.

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