JP2009127297A - Abnormality detector of construction machinery, and construction machinery including the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an abnormality detector of construction machinery, which can determine the occurrence of a failure even if a pressure sensor outputs a normal value, and the construction machinery which includes the abnormality detector. <P>SOLUTION: A drive control portion 32 determines that the pressure sensors 29A and 29B are in an abnormal state, when determining that a signal input from the pressure sensors 29A and 29B and indicating hydraulic pressure falls within a normal value, in the case of determining the nonusable state of the construction machinery by the signal input from a gate lock operation portion 26 and indicating the opened/closed state of a gate 26B. Thus, a failure in the pressure sensors 29A and 29B can be determined even if the hydraulic pressure detected by the pressure sensors 29A and 29B indicates the normal value. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an abnormality detection device for a construction machine that performs drive control of a turning mechanism of the construction machine and a construction machine including the same.

Conventionally, a hydraulic pump and a pilot pump driven by a prime mover, a hydraulic actuator for hydraulically driving a working element, a hydraulic pilot type control valve for controlling the flow of pressure oil from the hydraulic pump to the hydraulic actuator, and a pilot pump In a construction machine having an operation means for operating a hydraulic actuator via a control valve by a pilot pressure supplied from a pilot pressure, a pilot secondary pressure generated in the hydraulic pilot operation valve is detected by a pressure sensor, and an output of the pressure sensor Has deviated from between the upper limit value and the lower limit value during operation (normal range), the pressure sensor has been determined to be abnormal (see, for example, Patent Document 1).
Japanese Patent Application Laid-Open No. 2005-290674

  By the way, when the normal pressure sensor detects the pilot secondary pressure while the construction machine is in use, the output of the pressure sensor becomes a normal value that is approximately between the upper limit value and the lower limit value.

  For this reason, if the pressure sensor fails within the normal range, the failure of the pressure sensor could not be detected as long as a normal value was output even if the pressure sensor failed.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a construction machine abnormality detection device and a construction machine including the same that can perform failure determination even when a pressure sensor outputs a normal value.

  A turning drive control device according to one aspect of the present invention includes a hydraulic pump and a pilot pump driven by a prime mover, a hydraulic actuator for hydraulically driving a work element, and a flow of pressure oil from the hydraulic pump to the hydraulic actuator. In an abnormality detection device for detecting an abnormality of a construction machine, comprising: a hydraulic pilot control valve to be controlled; and an operation means for operating the hydraulic actuator via the control valve by a pilot pressure supplied from the pilot pump The pilot pump is disposed in a pilot line that transmits the pilot pressure from the pilot pump to the operation means, and transmits the pilot pressure to the operation means when the construction machine is used, and the pilot pressure operation means when the construction machine is not used. A shutoff valve that shuts off the transmission to the pilot pressure and the pilot pressure A hydraulic pressure detecting means for outputting, a usage status detecting means for detecting a usable state and an unusable state of the construction machine, and when the unusable state is detected by the usage status detecting means, the hydraulic pressure is detected. And an abnormality determination unit that determines an abnormality of the hydraulic pressure detection unit based on a detection result of the detection unit.

  The use state detecting means detects a usable state of the construction machine when the gate lock device that is opened and closed when the construction machine gets on and off the driver's seat is operated, and the gate lock device is activated. When it is not, the unusable state of the construction machine may be detected.

  In addition, the abnormality determination unit is configured to detect the hydraulic pressure when a detected value of the hydraulic pressure detection unit is within a predetermined normal range when an unusable state of the construction machine is detected by the usage state detection unit. It may be determined that the detection means is abnormal.

  Moreover, you may further provide the alerting | reporting means which alert | reports the abnormality of the said oil-pressure detection means to a driver | operator.

  A construction machine according to one aspect of the present invention includes the turning drive control device according to any one of the above.

  Advantageous Effects of Invention According to the present invention, it is possible to provide a specific effect that a construction machine abnormality detection device capable of performing failure determination even when the pressure sensor outputs a normal value and a construction machine including the same can be provided.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a construction machine abnormality detection device and a construction machine including the construction machine according to the present invention will be described.

  FIG. 1 is a side view showing a construction machine including the abnormality detection device of the present embodiment.

  An upper swing body 3 is mounted on the lower traveling body 1 of the construction machine via a swing mechanism 2. In addition to the boom 4, the arm 5, and the bucket 6, and the boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9 for hydraulically driving them, the upper swing body 3 is equipped with a cabin 10 and a power source. Is done.

"overall structure"
FIG. 2 is a block diagram showing the configuration of the construction machine including the abnormality detection device of the present embodiment. In FIG. 2, the mechanical power system is indicated by a double line, the high-pressure hydraulic line is indicated by a solid line, the pilot line is indicated by a broken line, and the electric drive / control system is indicated by a one-dot chain line.

  An engine 11 as a mechanical drive unit and a motor generator 12 as an assist drive unit are both connected to an input shaft of a speed reducer 13 as a booster. A main pump 14 and a pilot pump 15 are connected to the output shaft of the speed reducer 13. A control valve 17 is connected to the main pump 14 via a high pressure hydraulic line 16.

  The control valve 17 is a control device that controls the hydraulic system in the construction machine of the present embodiment. The control valve 17 includes hydraulic motors 1A (for right) and 1B (for left) for the lower traveling body 1, The boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9 are connected via a high pressure hydraulic line.

  In addition, a battery 19 is connected to the motor generator 12 via an inverter 18, and a turning motor 21 is connected to the battery 19 via an inverter 20.

  A resolver 22, a mechanical brake 23, and a turning speed reducer 24 are connected to the rotating shaft 21 a of the turning electric motor 21. Further, the operating device 27 is connected to the pilot pump 15 via a pilot line 15A. The pilot line 15A is provided with a shut-off valve 25, and the shut-off valve 25 is switched between a communication state and a shut-off state by an operation of the gate lock operation unit 26.

  The control device 17 and pressure sensors 29A and 29B are connected to the operating device 27 via hydraulic lines 28A and 28B, respectively. The pressure sensors 29A and 29B are connected to a controller 30 that performs drive control of the electric system of the construction machine according to the present embodiment.

  The construction machine of this embodiment is a hybrid construction machine that uses the engine 11, the motor generator 12, and the turning electric motor 21 as power sources. These power sources are mounted on the upper swing body 3 shown in FIG. Hereinafter, each part will be described.

"Configuration of each part"
The engine 11 is an internal combustion engine composed of, for example, a diesel engine, and its output shaft is connected to one input shaft of the speed reducer 13. The engine 11 is always operated during the operation of the construction machine.

  The motor generator 12 may be an electric motor capable of both power running operation and regenerative operation. Here, a motor generator that is AC driven by an inverter 20 is shown as the motor generator 12. The motor generator 12 can be constituted by, for example, an IPM (Interior Permanent Magnetic) motor in which a magnet is embedded in a rotor. The rotating shaft of the motor generator 12 is connected to the other input shaft of the speed reducer 13.

  The speed reducer 13 has two input shafts and one output shaft. A drive shaft of the engine 11 and a drive shaft of the motor generator 12 are connected to each of the two input shafts. Further, the drive shaft of the main pump 14 is connected to the output shaft. When the load on the engine 11 is large, the motor generator 12 performs a power running operation, and the driving force of the motor generator 12 is transmitted to the main pump 14 via the output shaft of the speed reducer 13. Thereby, driving of the engine 11 is assisted. On the other hand, when the load on the engine 11 is small, the driving force of the engine 11 is transmitted to the motor generator 12 via the speed reducer 13 so that the motor generator 12 generates power by regenerative operation. Switching between the power running operation and the regenerative operation of the motor generator 12 is performed by the controller 30 according to the load of the engine 11 and the like.

  The main pump 14 is a pump that generates hydraulic pressure to be supplied to the control valve 17. This hydraulic pressure is supplied to drive each of the hydraulic motors 1 </ b> A and 1 </ b> B, the boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9 via the control valve 17.

  The pilot pump 15 is a pump that generates a pilot pressure necessary for the hydraulic operation system. The configuration of this hydraulic operation system will be described later.

  The control valve 17 inputs the hydraulic pressure supplied to each of the hydraulic motors 1A, 1B, the boom cylinder 7, the arm cylinder 8 and the bucket cylinder 9 for the lower traveling body 1 connected via a high-pressure hydraulic line. It is a hydraulic control device which controls these hydraulically by controlling according to the above.

  The inverter 18 supplies electric power necessary for the power running operation of the motor generator 12 from the battery 19 to the motor generator 12, and at the same time, charges the battery 19 with electric power generated by the regenerative operation of the motor generator 12. It is an inverter provided between the machine 12 and the battery 19.

  The battery 19 is disposed between the inverter 18 and the inverter 20. As a result, when at least one of the motor generator 12 and the turning electric motor 21 is performing the power running operation, the electric power necessary for the power running operation is supplied, and at least one of them is performing the regenerative operation. The power source for storing the regenerative power generated by the regenerative operation as electrical energy.

  The inverter 20 is provided between the turning electric motor 21 and the battery 19 as described above, and performs operation control on the turning electric motor 21 based on a command from the controller 30. As a result, when the inverter controls the power of the turning electric motor 21, the necessary electric power is supplied from the battery 19 to the turning electric motor 21. Further, when the turning electric motor 21 is performing a regenerative operation, the battery 19 is charged with the electric power generated by the turning electric motor 21.

  The turning electric motor 21 may be an electric motor capable of both power running operation and regenerative operation, and is provided for driving the turning mechanism 2 of the upper turning body 3. During the power running operation, the rotational force of the rotational driving force of the turning electric motor 21 is amplified by the speed reducer 24, and the upper turning body 3 is subjected to acceleration / deceleration control to perform rotational motion. Further, due to the inertial rotation of the upper swing body 3, the number of rotations is increased by the speed reducer 24 and transmitted to the turning electric motor 21, and regenerative power can be generated. Here, as the electric motor 21 for turning, an electric motor driven by an inverter 20 by a PWM (Pulse Width Modulation) control signal is shown. The turning electric motor 21 can be constituted by, for example, a magnet-embedded IPM motor. Thereby, since a larger induced electromotive force can be generated, the electric power generated by the turning electric motor 21 at the time of regeneration can be increased.

  The charge / discharge control of the battery 19 is based on the state of charge of the battery 19, the operation state of the motor generator 12 (powering operation or regenerative operation), and the operation state of the turning motor 21 (powering operation or regenerative operation). Is done by.

  The resolver 22 is a sensor that detects the rotational position and the rotational angle of the rotating shaft 21A of the turning electric motor 21, and is mechanically connected to the turning electric motor 21 to rotate the rotating shaft 21A before the turning electric motor 21 rotates. The rotation angle and the rotation direction of the rotation shaft 21A are detected by detecting the difference between the position and the rotation position after the left rotation or the right rotation. By detecting the rotation angle of the rotation shaft 21A of the turning electric motor 21, the rotation angle and the rotation direction of the turning mechanism 2 are derived.

  The mechanical brake 23 is a braking device that generates a mechanical braking force, and mechanically stops the rotating shaft 21 a of the turning electric motor 21. This mechanical brake 23 is switched between braking (on) and releasing (off) by an electromagnetic switch.

  The turning speed reducer 24 is a speed reducer that reduces the rotational speed of the rotating shaft 21 a of the turning electric motor 21 and mechanically transmits it to the turning mechanism 2.

  The turning mechanism 2 can turn in a state where the mechanical brake 23 of the turning electric motor 21 is released, and in this state, the upper turning body 3 is turned leftward or rightward.

  The shut-off valve 25 is disposed in a pilot line 15A that transmits pilot pressure from the pilot pump 15 to the operating device 27. When the relay 25A is switched on / off, power is supplied from a DC power supply (24V). As a result, the communication state / blocking state is switched. When the construction machine is used, the pilot pressure is transmitted to the operating device 27 when the construction machine is used, and when the construction machine is not used, the pilot pressure is blocked and the transmission of the pilot pressure to the operating device 27 is blocked. The switching control of the shutoff valve 25 is performed by the gate lock operation unit 26.

  The gate lock operation unit 26 is a gate lock device for switching between a usable (operable) state and an unusable (unoperable) state of the construction machine. The gate lock operation unit 26 is provided for preventing malfunction of the construction machine. Here, the gate lock operation unit 26 will be described with reference to FIGS. 3 and 4.

  FIG. 3 is a perspective view showing the driver's seat and its surroundings of the construction machine of the present embodiment.

  Consoles 10B are disposed on both sides of the driver's seat 10A disposed in the cabin 10, and a pair of operation levers 27A are disposed on the pair of consoles 10B. The driver's seat 10A can be boarded and exited from the left side with respect to the cabin front direction, and a gate lock operation unit 26 is disposed on the left console 10B.

  FIG. 4 is a side view showing the console on the left side of the driver's seat of the construction machine of the present embodiment.

  The gate lock operation unit 26 disposed on the left console 10B includes a gate lock lever 26A, a gate 26B, and a limit switch 26C.

  The gate lock operation unit 26 is disposed on the side of the driver's seat disposed in the cabin of the upper swing body 3, and is an operation for opening and closing the gate 26B disposed in the getting-on / off unit for the driver's seat. Part. The gate 26B and the gate lock lever 26A are connected by a wire. When the gate lock lever 26A is pulled up, the gate 26B is closed (indicated by a solid line), and when the gate lock lever 26A is lowered, the gate 26B is opened. (State indicated by a broken line). When this gate is closed, the driver cannot get out of the driver's seat and can get off when it is opened.

  The limit switch 26C is a sensor for detecting the operation of the gate lock lever 26A, and is turned on when the gate lock lever 26A is pulled up and turned off when the gate lock lever 26A is lowered. When the limit switch 26C is turned on, the relay 25A of the cutoff valve 25 is turned on, and when the limit switch 26C is turned off, the relay 25A is turned off. Thus, the shutoff valve 25 is switched by the limit switch 26C. A signal indicating ON / OFF of the limit switch 26C is also input to the controller 30.

  In a state where the gate lock lever 26A is pulled up and the gate 26B is closed, the relay 25A is turned on and the shutoff valve 25 is brought into a communication state, so that the construction machine can be used (operated). On the other hand, when the gate lock lever 26A is lowered and the gate 26B is opened, the relay 25A is turned off and the shutoff valve 25 is shut off, so that the construction machine cannot be used (cannot be operated). It becomes a state. This is to prevent malfunction.

  2 is an operation device for operating the electric motor 21 for turning, the lower traveling body 1, the boom 4, the arm 5, and the bucket 6, and includes levers 27A and 27B and a pedal 27C. The lever 27 </ b> A is a lever for operating the turning electric motor 21 and the arm 5, and is provided in the vicinity of the driver seat of the upper turning body 3. The lever 27B is a lever for operating the boom 4 and the bucket 6 and is provided in the vicinity of the driver's seat. The pedal 27C is a pair of pedals for operating the lower traveling body 1 and is provided under the feet of the driver's seat.

  The operating device 27 converts the hydraulic pressure (primary hydraulic pressure) supplied through the pilot line 15A into a hydraulic pressure (secondary hydraulic pressure) corresponding to the operation amount of the driver and outputs the converted hydraulic pressure. The secondary hydraulic pressure output from the operating device 27 is supplied to the control valve 17 through the hydraulic line 28A and is detected by the pressure sensors 29A and 29B.

  When each of the levers 27A, 27B and the pedal 27C is operated, the control valve 17 is driven through the hydraulic line 28A, whereby the hydraulic motors 1A, 1B, the boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9 By controlling the hydraulic pressure, the lower traveling body 1, the boom 4, the arm 5, and the bucket 6 are driven.

  The mechanical brake 23 is configured to be released by the controller 30 when any of the levers 27A and 27B or the pedal 27C is operated.

  The hydraulic line 28A supplies hydraulic pressures necessary for driving the hydraulic motors 1A and 1B, the boom cylinder 7, the arm cylinder 8, and the bucket cylinder to the control valve.

  The pressure sensor 29A detects the hydraulic pressure in the hydraulic line 28B when the lever 27A is operated to turn the upper swing body 3 in the right direction. An electrical signal representing the hydraulic pressure is input to the controller 30. Similarly, the pressure sensor 29B detects the hydraulic pressure in the hydraulic line 28B when the lever 27A is operated to turn the upper swing body 3 leftward. An electrical signal representing the hydraulic pressure is input to the controller 30.

"Controller 30"
The controller 30 is a control device that performs drive control of the construction machine according to the present embodiment, and includes a speed command conversion unit 31, a drive control unit 32, and a turning drive control device 40. The controller 30 includes a CPU (Central Processing Unit) and an arithmetic processing device including an internal memory, and the speed command conversion unit 31, the drive control unit 32, and the turning drive control device 40 include the CPU of the controller 30 in the internal memory. It is an apparatus realized by executing a stored drive control program.

  The speed command conversion unit 31 is an arithmetic processing unit that converts signals input from the pressure sensors 29A and 29B into speed commands. As a result, the operation amount of the lever 27A is converted into a speed command (rad / s) for driving the turning electric motor 21 to rotate. This speed command is input to the drive control unit 32 and the turning drive control device 40.

  The drive control unit 32 detects an abnormality of the pressure sensors 29A and 29B based on a signal indicating the open / closed state of the gate 26B input from the gate lock operation unit 26 and a signal indicating the hydraulic pressure input from the pressure sensors 29A and 29B. I do.

  The drive control unit 32 is a control device for performing operation control of the motor generator 12 (switching between power running operation or regenerative operation) and charge / discharge control of the battery 19. The drive control unit 32 switches between the power running operation and the regenerative operation of the motor generator 12 according to the load state of the engine 11 and the charge state of the battery 19. The drive control unit 32 performs charge / discharge control of the battery 19 via the inverter 18 by switching between the power running operation and the regenerative operation of the motor generator 12.

  Here, in the control system of the construction machine of the present embodiment, the rotation direction in which the rotating shaft 21a of the turning electric motor 21 rotates counterclockwise is referred to as “forward rotation”, and the control amount represents the drive in the forward rotation direction. Add a positive sign. On the other hand, the rotation direction in which the rotating shaft 21a of the turning electric motor 21 rotates clockwise is referred to as “reverse rotation”, and a negative sign is assigned to the control amount indicating the drive in the reverse rotation direction. Forward rotation corresponds to turning of the upper swing body 3 in the right direction, and reverse rotation corresponds to turning of the upper swing body in the left direction.

"Swivel drive control device 40"
FIG. 5 is a control block diagram showing the configuration of the turning drive control device 40 for the construction machine according to the present embodiment.

  The turning drive control device 40 is a control device for performing drive control of the turning electric motor 21 via the inverter 20, and includes a drive command generating unit 50 that generates a drive command for driving the turning electric motor 21, and a main command. A control unit 60 is included.

  The drive command generator 50 receives a speed command output from the speed command converter 31 in accordance with the amount of operation of the lever 27A, and the drive command generator 50 generates a drive command based on the speed command. The drive command output from the drive command generation unit 50 is input to the inverter 20, and the turning electric motor 21 is AC-driven by the inverter 20 using the PWM control signal.

  The main control unit 60 is a control unit that performs peripheral processing necessary for the control processing of the drive command generation unit 50. Specific processing contents will be described each time in related sections.

  The turning drive control device 40 controls the switching between the power running operation and the regenerative operation when driving the turning electric motor 21 according to the operation amount of the operation lever 27A, and also controls the battery 19 via the inverter 20. Charge / discharge control is performed.

"Drive command generation unit 50"
The drive command generator 50 includes a subtractor 51, a PI (Proportional Integral) controller 52, a torque limiter 53, a torque limiter 54, a subtractor 55, a PI controller 56, a current converter 57, and a turning motion detector 58. including. A speed command (rad / s) for turning drive corresponding to the operation amount of the lever 27A is input to the subtractor 51 of the drive command generation unit 50.

  The subtractor 51 subtracts the rotational speed (rad / s) of the turning electric motor 21 detected by the turning motion detector 58 from the value of the speed command (hereinafter referred to as speed command value) corresponding to the operation amount of the lever 27A. Output the deviation. This deviation is used in PI control for causing the rotational speed of the turning electric motor 21 to approach the speed command value (target value) in the PI control unit 52 described later.

  Based on the deviation input from the subtractor 51, the PI control unit 52 performs PI control so that the rotation speed of the turning electric motor 21 approaches the speed command value (target value) (that is, this deviation is reduced). And a torque current command necessary for that is calculated. The generated torque current command is input to the torque limiter 53.

  The torque limiter 53 performs a process of limiting the value of the torque current command (hereinafter, torque current command value) according to the operation amount of the lever 27A. Here, the torque limit means that the torque current command value input to the torque limiter 53 is limited to a value (allowable value) or less allowed by the torque limit characteristic and output.

The torque limiter 53 is
Torque current command value input from the PI control unit 52 using a torque limiting characteristic in which the absolute value of the torque current command value (allowable value) allowed by the limitation gradually increases as the operation amount of the lever 27A increases. Limit. Such limitation of the torque current command value is performed in order to suppress this because the controllability deteriorates when the torque current command value calculated by the PI control unit 52 increases rapidly.

  The torque limiter 54 limits the torque current command value input from the torque limiter 53 so that the torque generated by the torque current command input from the torque limiter 53 is less than or equal to the allowable maximum torque value of the turning electric motor 21. To do. The torque current command value is limited with respect to the bi-directional rotation of the upper swing body 3 in the left direction and the right direction, similarly to the torque limiting unit 53.

  Here, the torque limiting characteristic for limiting the torque current command value by the torque limiting unit 54 is that even if the torque current command value is limited by the torque limiting unit 54, the torque is turned by touching the earth and sand on which the bucket 6 is stacked. It is set so that a torque current command for generating a driving torque capable of rotating the rotating shaft 21A of the turning electric motor 21 in a state where the load of the electric motor 21 is large can be output. Note that data representing the characteristic for limiting the torque current command value is stored in the internal memory of the main control unit 60, read by the CPU of the main control unit 60, and input to the torque limiting unit 54.

  The subtractor 55 outputs a deviation obtained by subtracting the output value of the current converter 57 from the torque current command value input from the torque limiter 54. This deviation is the torque current that is input via the torque limiter 54 to the drive torque of the turning electric motor 21 that is output from the current converter 57 in a feedback loop that includes a PI controller 56 and a current converter 57 described later. It is used for PI control to approach the torque represented by the command value (target value).

  Based on the deviation input from the subtractor 55, the PI control unit 56 performs PI control so as to reduce this deviation, and generates a torque current command as a final drive command to be sent to the inverter 20. The inverter 20 PWM drives the turning electric motor 21 based on the torque current command input from the PI control unit 56.

  The current converter 57 detects the motor current of the turning electric motor 21, converts it into a value corresponding to the torque current command, and inputs it to the subtractor 55.

  The turning motion detector 58 detects a change in the rotational position of the turning electric motor 21 detected by the resolver 22 (that is, turning of the upper turning body 3), and the rotation of the turning electric motor 21 from the temporal change in the rotational position. The speed is derived by differential operation. Data representing the derived rotational speed is input to the subtractor 51 and the main control unit 60.

  In the drive command generation unit 50 configured as described above, when the speed command is output from the speed command conversion unit 31 by operating the lever 27A, the deviation between the speed command value and the rotation speed is input to the PI control unit 52. A torque current command value for reducing this deviation is output. The torque current command value is input to the subtractor 55 after being limited by the torque limiters 53 and 54, and a deviation from the output of the current converter 57 is output. This deviation is input to the PI control unit 56, the final torque current command value is calculated, the turning electric motor 21 is driven and controlled by the inverter 20, and the upper turning body 3 turns to a desired position via the turning mechanism 2. Driven.

"Abnormality detection processing"
FIG. 6 is a diagram illustrating a procedure of abnormality detection processing by the abnormality detection device for a construction machine according to the present embodiment. This is a process executed by the drive control unit 32. The drive control unit 32 is detected by a signal indicating ON / OFF of the limit switch 26C input from the gate lock operation unit 26 and the pressure sensors 29A and 29B. The abnormality of the pressure sensors 29A and 29B is detected based on the signal representing the hydraulic pressure.

  The drive control unit 32 determines whether or not the limit switch 26C is off (step S1). This determination is performed in order to determine whether the construction machine is in use. If it is off, the construction machine is in an unusable state.

  If it is off, the drive control unit 32 determines whether or not the hydraulic pressure detected by the pressure sensor 29A is equal to or lower than a predetermined lower limit value (step S2). This determination is made when the limit switch 26C is off and the pressure detected by the pressure sensor 29A is within a range of normal hydraulic pressure (hereinafter referred to as a normal value) that can be detected during use of the construction machine. This is because the pressure sensor 29A is considered to be abnormal, and is compared with the lower limit value. This lower limit value is set to the lower limit value of the normal value range.

  When it is determined in step S2 that the hydraulic pressure is higher than the lower limit value, the drive control unit 32 determines whether or not the hydraulic pressure detected by the pressure sensor 29A is equal to or higher than a predetermined upper limit value (step S3). This determination is performed in order to compare with the upper limit value in order to determine whether the hydraulic pressure is within the normal value range when the limit switch 26C is off. This upper limit value is set to the upper limit value of the normal value range.

  If the drive control unit 32 determines in step S3 that the hydraulic pressure is lower than the upper limit value, the drive control unit 32 determines that the pressure sensor 29A is abnormal (step S4). This is because if the hydraulic pressure detected by the pressure sensor 29A is within a normal value range when the limit switch 26C is off (a state in which the construction machine cannot be used), it is considered that the pressure sensor 29A is abnormal.

  When it is determined in step S2 that the hydraulic pressure detected by the pressure sensor 29A is equal to or lower than the lower limit value, or when step S4 is completed, the drive control unit 32 determines that the hydraulic pressure detected by the pressure sensor 29B is a predetermined lower limit. It is determined whether or not the value is equal to or less than the value (step S5). As in step S2, if the oil pressure detected by the pressure sensor 29B is within the normal value range when the limit switch 26C is off, it is considered that the pressure sensor 29B is abnormal. This is for comparison. This lower limit value is set to the lower limit value of the normal value range.

  When it is determined in step S5 that the hydraulic pressure is higher than the lower limit value, the drive control unit 32 determines whether or not the hydraulic pressure detected by the pressure sensor 29B is equal to or higher than a predetermined upper limit value (step S6). This determination is performed in order to compare with the upper limit value in order to determine whether the hydraulic pressure is within the normal value range when the limit switch 26C is off. This upper limit value is set to the upper limit value of the normal value range.

  If the drive control unit 32 determines in step S6 that the hydraulic pressure is lower than the upper limit value, the drive control unit 32 determines that the pressure sensor 29B is abnormal (step S7). This is because if the hydraulic pressure detected by the pressure sensor 29B is within a normal value range when the limit switch 26C is off (a state in which the construction machine cannot be used), it is considered that the pressure sensor 29B is abnormal. When the process of step S7 ends, all the processes end.

  If the drive control unit 32 determines in step S6 that the hydraulic pressure detected by the pressure sensor 29B is greater than or equal to the upper limit value, the process ends. This is because no abnormality was found.

  If the drive control unit 32 determines in step S1 that the limit switch 26C is on, the drive control unit 32 repeatedly executes step S1. The construction machine abnormality detection device according to the present embodiment detects an abnormality (failure) when the detection values of the pressure sensors 29A and 29B are within the normal value range. For this reason, the construction machine cannot be used. It is because it is a premise that it is a state.

  Note that the processing of steps S1 to S7 is processing executed to detect a failure of the pressure sensors 29A and 29B when the limit switch 26C is in an off state, that is, when the construction machine cannot be used. Therefore, these processes may be executed, for example, when the limit switch 26C is turned off by lowering the gate lock lever 26A at the end of the specification of the construction machine.

  As described above, according to the abnormality detection device for a construction machine of the present embodiment, even if the hydraulic pressure detected by the pressure sensors 29A and 29B shows a normal value, it is possible to determine whether the pressure sensors 29A and 29B are faulty.

  In the above description, the turning motor 21 is an AC motor that is PWM-driven by the inverter 20, and the form in which the resolver 22 and the turning motion detection unit 58 are used to detect the rotation speed has been described. A DC motor may be used. In this case, the inverter 20, the resolver 22, and the turning motion detection unit 58 are not necessary, and the value detected by the tachometer generator of the DC motor may be used as the rotation speed.

  In the above description, the PI control is used for calculating the torque current command. However, instead of this, robust control, adaptive control, proportional control, integral control, or the like may be used.

  Further, in the above, the form in which the turning mechanism 2 is motorized in the hybrid type construction machine has been described, but the application target of the abnormality detection device of the present embodiment is not limited to the hybrid type, It may be a construction machine in which all working elements are hydraulically driven. For this reason, when the abnormality detection device according to the present embodiment is applied to a construction machine that does not include the motor generator 12 and the turning electric motor 21 and is also hydraulically driven, the pressure sensors 29A and 29B are unnecessary. Therefore, the hydraulic pressure in the control valve 17 may be monitored by the controller 32 instead of the pressure sensors 29A and 29B.

  The exemplary abnormality detection device of the present embodiment and the construction machine including the same have been described above, but the present invention is not limited to the specifically disclosed embodiment, and is claimed. Various modifications and changes can be made without departing from the scope.

It is a side view which shows the construction machine containing the abnormality detection apparatus of this Embodiment. It is a block diagram showing the structure of the construction machine containing the abnormality detection apparatus of this Embodiment. It is a perspective view which shows the driver's seat of the construction machine of this Embodiment, and its periphery. It is a side view which shows the console in the left side of the driver's seat of the construction machine of this Embodiment. It is a control block diagram which shows the structure of the turning drive control apparatus 40 of the construction machine of this Embodiment. It is a figure which shows the procedure of the abnormality detection process by the abnormality detection apparatus of the construction machine of this Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lower traveling body 1A, 1B Traveling mechanism 2 Turning mechanism 3 Upper turning body 4 Boom 5 Arm 6 Bucket 7 Boom cylinder 8 Arm cylinder 9 Bucket cylinder 10 Cabin 10A Driver's seat 10B Console 11 Engine 12 Motor generator 13 Reducer 14 Main pump DESCRIPTION OF SYMBOLS 15 Pilot pump 15A Pilot line 16 High pressure hydraulic line 17 Control valve 18 Inverter 19 Battery 20 Inverter 21 Turning electric motor 23 Mechanical brake 24 Turning reduction gear 25 Shutoff valve 25A Relay 26 Gate lock operation part 26A Gate lock lever 26B Gate 26C Limit switch 27 Operating device 27A, 27B Lever 27C Pedal 28A, 28B Hydraulic line 29A, 29B Pressure sensor 30 Controller 31 Speed finger Command converter 32 Drive controller 40 Turning drive controller 50 Drive command generator 51 Subtractor 52 PI controller 53 Torque limiter 54 Torque limiter 55 Subtractor 56 PI controller 57 Current converter 58 Turn motion detector 60 Main Control unit

Claims (5)

A hydraulic pump and a pilot pump driven by a prime mover, a hydraulic actuator for hydraulically driving a working element, a hydraulic pilot type control valve for controlling a flow of pressure oil from the hydraulic pump to the hydraulic actuator, and the pilot In an abnormality detection device for detecting an abnormality of a construction machine comprising an operation means for operating the hydraulic actuator via the control valve by a pilot pressure supplied from a pump,
The pilot pump is disposed in a pilot line that transmits the pilot pressure from the pilot pump to the operation means, and transmits the pilot pressure to the operation means when the construction machine is used, and to the operation means of the pilot pressure when the construction machine is not used. A shut-off valve that shuts off the transmission of
Oil pressure detecting means for detecting the pilot pressure;
A use state detecting means for detecting a usable state and an unusable state of the construction machine;
An abnormality detection device for a construction machine, comprising: an abnormality determination unit that determines an abnormality of the hydraulic pressure detection unit based on a detection value of the hydraulic pressure detection unit when an unusable state is detected by the use state detection unit .   The use state detecting means detects a usable state of the construction machine when the gate lock device that is opened and closed when the construction machine gets on and off the driver's seat is operated, and the gate lock device is operated. The construction machine abnormality detection device according to claim 1, which detects an unusable state of the construction machine when there is not.   The abnormality determination unit is configured to detect the hydraulic pressure detection unit when a detected value of the hydraulic pressure detection unit is within a predetermined normal range when an unusable state of the construction machine is detected by the use state detection unit. The abnormality detection device for a construction machine according to claim 1, wherein the abnormality is determined to be abnormal.   The abnormality detection device for a construction machine according to any one of claims 1 to 3, further comprising notification means for notifying a driver of an abnormality in the hydraulic pressure detection means.   A construction machine comprising the construction machine abnormality detection device according to any one of claims 1 to 4.

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