JP6847592B2 - Excavator - Google Patents

Description

The present invention relates to an excavator in which the swivel mechanism is electrified.

Conventionally, in a shovel that swivels and drives a swivel body using an electric motor, a technique for urgently stopping the swivel body when a predetermined operation (for example, an operation of a gate lock lever) is performed by an operator who senses an abnormality during the swivel. It has been proposed (for example, Patent Document 1 and the like).

By adopting such a configuration, the operator can detect an abnormality and perform a predetermined operation such as lowering the gate lock lever, so that the swivel body can be stopped urgently, and the excavator that drives the swivel body with an electric motor. Can increase the safety of.

Japanese Unexamined Patent Publication No. 2012-82607

However, in order to further enhance the safety, it is desirable that the abnormality is detected and the fail-safe process corresponding to the abnormality is performed before the operator detects the abnormality.

Therefore, in view of the above problems, it is an object of the present invention to provide higher safety in an excavator that electrically drives a swivel body.

In order to achieve the above object, in one embodiment,
With a swivel body
The electric motor that drives the swivel body and
A speed detection unit that detects the rotation speed of the electric motor,
A current detection unit that detects the current of the electric motor, and
An operation amount detection unit that detects the operation amount of the operation lever that operates the swivel body, and
A first control unit that controls the drive of the electric motor based on the detection value of the speed detection unit, the detection value of the current detection unit, and the detection value of the operation amount detection unit.
Information corresponding to the operation state of the gate lock lever, the detection value of the speed detection unit, the detection value of the current detection unit, the detection value of the operation amount detection unit, and the electric motor generated by the first control unit. based on at least one, of the control command value for controlling driving, the detection of abnormality of the operation of the swing body, or a second control unit for performing stop control of the swivel body, Ru provided with,
Excavators are provided.

According to the above-described embodiment, it is possible to provide higher safety in the excavator that electrically drives the swivel body.

It is a side view of an excavator. It is a figure which shows an example of the structure of a shovel. It is a figure which shows an example of the structure of the power storage system of a shovel. It is a functional block diagram which shows typically an example of the structure of the turning control system of a shovel. It is a flowchart which shows typically an example of the 1st monitoring process by a controller (monitoring unit). It is a flowchart which shows the other example of the 1st monitoring process by a controller (monitoring unit) schematicly. It is a flowchart which shows typically an example of the 2nd monitoring process by a controller (monitoring part). It is a flowchart which shows the other example of the 2nd monitoring process by a controller (monitoring unit) schematicly. It is a figure which shows another example of the structure of a shovel. It is a functional block diagram which shows another example of the structure of the turning control system of a shovel. It is a flowchart which shows typically an example of the 1st monitoring process by a monitoring device.

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

[Excavator configuration]
First, the configuration of the excavator according to the present embodiment will be described with reference to FIGS. 1 to 4.

FIG. 1 is a side view showing an excavator according to the present embodiment.

As shown in FIG. 1, the lower traveling body 1 hydraulically driven by the traveling hydraulic motors 1A and 1B (see FIGS. 2 and 7) as hydraulic actuators is mounted with the upper rotating body 3 via the swivel mechanism 2. To. A boom 4 is attached to the upper swing body 3. An arm 5 is attached to the tip of the boom 4, and a bucket 6 is attached to the tip of the arm 5. The boom 4, arm 5, and bucket 6 as attachments are hydraulically driven by the boom cylinder 7, arm cylinder 8, and bucket cylinder 9 as hydraulic actuators, respectively. Further, the upper swing body 3 is provided with a cabin 10 on which an operator is boarded, and is also equipped with an engine 11 (see FIGS. 2 and 7) and the like.

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

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

The engine 11 as the main drive unit of the excavator according to the present embodiment (for example, a diesel engine using light oil as fuel) and the motor generator 12 as the assist drive unit are connected to two input shafts of the speed reducer 13, respectively. To. A main pump 14 and a pilot pump 15 are connected in series to the output shaft of the speed reducer 13. That is, the engine 11 can drive the main pump 14 and the pilot pump 15 via the speed reducer 13, and the motor generator 12 can assist the engine 11 to drive the main pump 14 and the pilot pump 15. A control valve 17 is connected to the main pump 14 via a high-pressure hydraulic line 16.

The main pump 14 is, for example, a variable displacement hydraulic pump, and the stroke length of the piston can be adjusted by controlling the angle (tilt angle) of the swash plate, and the discharge flow rate (discharge pressure) can be controlled.

The pilot pump 15 is, for example, a fixed displacement hydraulic pump. The pilot pump 15 is connected to the operating device 26 via the pilot line 25.

The control valve 17 is a flood control device that controls the hydraulic system in response to the operation of the operation device 26 by the operator. The traveling hydraulic motor 1A (for right), 1B (for left), boom cylinder 7, arm cylinder 8, bucket cylinder 9, and the like are connected to the control valve 17 via a high-pressure hydraulic line. The control valve 17 is provided between the main pump 14 and each hydraulic actuator, and is a plurality of hydraulic control valves (direction switching valves) that control the flow rate and flow direction of the hydraulic oil supplied from the main pump 14 to each of the hydraulic actuators. ) Is included in the valve unit.

The operation device 26 includes levers 26A and 26B and pedals 26C, and is an operation input means for the operator to operate each operation element (lower traveling body 1, upper turning body 3, boom 4, arm 5, bucket 6, etc.). is there. In other words, the operating device 26 includes each hydraulic actuator (running hydraulic motors 1A, 1B, boom cylinder 7, arm cylinder 8, bucket cylinder 9, etc.) for driving each operating element, and an electric actuator (swivel motor 21) described later. It is an operation input means for performing operations such as. The operating device 26 (lever 26A, 26B, and pedal 26C) is connected to the control valve 17 and the pressure sensor 29, respectively, via the hydraulic line 27 and the hydraulic line 28. As a result, a pilot signal (pilot pressure) corresponding to the operating state of the lower traveling body 1, the boom 4, the arm 5, the bucket 6 and the like in the operating device 26 is input to the control valve 17. The pressure sensor 29 is connected to the controller 30. As a result, a pressure signal (pressure detection value) according to the operating state of the lower traveling body 1, the upper swinging body 3, the boom 4, the arm 5, the bucket 6 and the like in the operating device 26 is input to the controller 30.

The levers 26A and 26B are arranged on the left side and the right side when viewed from the operator seated in the driver's seat in the cabin 10, respectively, and are arranged in the front-rear direction and the left-right direction with reference to the neutral state (the state in which the operation is not performed). It is configured to be tiltable. That is, the upper swing body 3, the boom 4, and the arm 5 are used for the front-rear tilt of the lever 26A, the left-right tilt of the lever 26A, the front-back tilt of the lever 26B, and the left-right tilt of the lever 26B. , And any of the bucket 6 can be arbitrarily set as the operation target. Hereinafter, the operation pattern of the levers 26A and 26B will be described on the premise that the operation pattern is a JIS (ISO) pattern, that is, the operation of the upper swing body 3 is performed by tilting the lever 26A from the neutral state to the left-right direction. I do.

Further, a gate lock switching valve 36 is provided on the pilot line 25 between the pilot pump 15 and the operating device 26.

The gate lock switching valve 36 communicates with the pilot line 25 according to the operation state of the gate lock lever 32, which is an operation unit for opening / closing the gate provided at the entrance / exit portion to the driver's seat in the cabin 10. Switch the non-communication state. Specifically, the gate lock switching valve 36 responds to a gate lock lever signal (ON / OFF) output from the gate lock lever switch (gate lock lever SW) 34 linked to the operating state of the gate lock lever 32. This is an electromagnetic switching valve that switches ON / OFF of the electromagnetic solenoid. The gate lock lever SW34 is turned off when the gate lock lever 32 is lowered (a state in which the boarding / alighting portion for the driver's seat is open). Then, when the gate lock lever signal (voltage signal equal to or lower than a predetermined threshold voltage) indicating the OFF state is input from the gate lock lever SW34, the gate lock switching valve 36 puts the pilot line 25 into a non-communication state and causes the pilot pump 15 to be in a non-communication state. The supply of hydraulic oil to the operating device 26 is cut off. On the other hand, the gate lock lever SW34 is turned on when the gate lock lever 32 is raised (when the boarding / alighting portion for the driver's seat is closed). Then, when the gate lock lever signal (voltage signal higher than a predetermined threshold voltage) indicating the ON state is input from the gate lock lever SW34, the gate lock switching valve 36 sets the pilot line 25 in a communicating state and starts from the pilot pump 15. Hydraulic oil (pilot pressure) is supplied to the operating device 26. When the gate lock lever 32 is raised, it can be determined that the operator is seated in the cockpit and is in a maneuverable state. Therefore, the pilot pressure is supplied to the operating device 26 only when the gate lock lever 32 is pulled up, thereby preventing the operation of each hydraulic actuator due to an unintended operation input to the operating device 26. That is, when the gate lock lever is lowered, the operation of each hydraulic actuator is locked, and when the gate lock lever is raised, the operation of each hydraulic actuator is unlocked (unlocked). Hereinafter, the state in which the gate lock lever 32 is lowered is referred to as a "locked state", and the state in which the gate lock lever 32 is raised is referred to as an "unlocked state".

In the figure, the gate lock switching valve 36 represents a case where the gate lock lever 32 is raised (the gate lock lever SW34 is turned on), and the pilot pressure is supplied from the pilot pump 15 to the operating device 26. Has been done.

A power storage system 120 including a capacitor 19 (see FIG. 3) as an example of a power storage device is connected to the motor generator 12 via an inverter 18A.

Further, in the excavator according to the present embodiment, the swivel mechanism 2 is electrified, and a swivel electric motor 21 for driving the swivel mechanism 2 (that is, the upper swivel body 3) is provided. The swivel motor 21 is connected to the power storage system 120 via the inverter 18B. Further, the turning electric motor 21 generates regenerative power generation in response to the turning deceleration operation of the upper turning body 3. A resolver 22, a mechanical brake 23, and a turning speed reducer 24 are connected to the rotating shaft 21A of the turning electric motor 21.

The turning electric motor 21 is configured to be able to realize both a power running operation in which the upper turning body 3 is swiveled and driven and a regenerative operation in which the upper swivel body 3 is regeneratively braked (swivel braking by generating regenerative power). During power running, the power of the swivel motor 21 is increased by the swivel reducer 24 (that is, the drive torque is increased), and the upper swivel body 3 is swiveled. Further, during the regenerative operation (that is, when the upper swing body 3 is swiveled and decelerated), the inertial rotational force of the upper swivel body 3 is transmitted to the swivel electric motor 21 via the swivel speed reducer 24 to generate regenerative power (that is, when the upper swivel body 3 is swiveled and decelerated). That is, the upper swivel body 3 is swiveled and braked). The swivel motor 21 according to the present embodiment is driven by the three-phase AC power supplied from the inverter 18B. The swivel motor 21 can include, for example, an IPM (Interior Permanent Magnet) motor. As a result, a larger induced electromotive force can be generated, so that the power generated by the turning electric motor 21 can be increased during regenerative braking.

The resolver 22 (an example of the speed detection unit) is a known detection means for detecting the rotation position (rotation angle), rotation speed, and the like of the turning electric motor 21. The resolver 22 transmits a detection signal (detection value) corresponding to the detected rotation angle and rotation speed to the controller 30.

If the rotation angle and rotation speed of the turning electric motor 21 can be detected, an arbitrary sensor (for example, an encoder or the like) may be used instead of the resolver 22.

The mechanical brake 23 is a known mechanical braking means for turning and braking the upper turning body 3. The mechanical brake 23 rotates integrally with the rotating shaft 21A and can move in the direction of the rotating shaft 21A (for example, spline-coupled to the rotating shaft 21A) and a disc that does not rotate and can move in the direction of the rotating shaft 21A (for example). A braking force torque is generated by surface contact with a plate (spline-coupled to the inner surface of the case, which is a fixed portion). The mechanical brake 23 can mechanically stop the rotating shaft 21A of the turning electric motor 21 and maintain the stopped state of the upper turning body 3. Further, the mechanical brake 23 can decelerate and stop the swivel mechanism 2 (upper swivel body 3) by operating the swivel mechanism 2 (upper swivel body 3) in a swivel state.

The turning speed reducer 24 is a means for increasing the force (increasing the torque) by decelerating the output (torque) of the turning electric motor 21. The swivel speed reducer 24 is connected to the swivel mechanism 2 to reduce the output of the swivel electric motor 21 and directly drive the swivel mechanism 2 to swivel. That is, the swivel electric motor 21 swivels and drives the swivel mechanism 2 (upper swivel body 3) via the swivel speed reducer 24.

Further, a current sensor 21s is provided in the power path between the turning electric motor 21 and the inverter 18B. The current sensor 21s detects the current of the turning electric motor 21. The current sensor 21s may be a magnetic sensor using a magnetoresistive effect, or a direct measurement type sensor using a shunt resistance or the like, as long as it can detect the current of the turning electric motor 21.

Since the swivel motor 21 is driven by the three-phase (U-phase, V-phase, W-phase) AC power supplied from the inverter 18B, the current sensor 21s detects the current of at least two of the three phases. It is provided in a possible mode (that is, a mode including a plurality of current sensors). Further, the current sensor 21s may be built in the inverter 18B and may be in a mode of detecting the current output from the inverter 18B.

The controller 30 is a main control device that controls the drive of the excavator. The controller 30 is composed of, for example, an arithmetic processing device (microcomputer) including a CPU, ROM, RAM, I / O, etc., and is driven by executing various drive control programs stored in the ROM on the CPU. Control is realized.

The controller 30 converts the pressure signal supplied from the pressure sensor 29 (a signal indicating the operating state of the upper swivel body 3 in the operating device 26) into the speed command C, and controls the drive of the swivel motor 21. Details will be described later.

The pressure signal (pressure detection value) supplied from the pressure sensor 29 is a signal representing the amount of operation in the operating device 26 (lever 26A) for rotating the swivel mechanism 2 (that is, the upper swivel body 3).

Further, the controller 30 controls the operation of the motor generator 12 (switching between electric (assist) operation and power generation operation), and drives and controls the buck-boost converter 100 (see FIG. 3) to control the capacitor 19 (see FIG. 3). ) Charge / discharge control. The controller 30 is a step-up / down converter 100 based on the charging state of the capacitor 19, the operating state of the motor generator 12 (electric (assist) operation or power generation operation), and the operating state of the turning motor 21 (power running operation or regenerative operation). It controls switching between the step-up operation and the step-down operation, thereby controlling the charging and discharging of the capacitor 19.

FIG. 3 is a circuit diagram showing an example of the configuration of the power storage system 120.

The power storage system 120 includes a capacitor 19, a buck-boost converter 100, a DC bus 110, and the like.

The DC bus 110 controls the transfer of electric power between the capacitor 19, the motor generator 12, and the turning motor 21. The capacitor 19 is provided with a capacitor voltage detection unit 112 for detecting the voltage value and the current value of the capacitor 19, and a capacitor current detection unit 113. The capacitor voltage value and the capacitor current value detected by the capacitor voltage detection unit 112 and the capacitor current detection unit 113 are supplied to the controller 30.

The buck-boost converter 100 switches between a step-up operation and a step-down operation so that the DC bus voltage value falls within a certain range according to the operating state of the motor generator 12 and the turning electric motor 21. The DC bus 110 is arranged between the inverters 18A and 18B and the buck-boost converter 100, and the capacitor 19, the motor generator 12, and the turning motor 21 transfer and receive electric power via the DC bus 110.

Switching control between the step-up operation and the step-down operation of the buck-boost converter 100 is performed by the DC bus voltage value detected by the DC bus voltage detection unit 111, the capacitor voltage value detected by the capacitor voltage detection unit 112, and the capacitor current detection unit 113. It is executed by the controller 30 based on the detected capacitor current value.

FIG. 4 is a functional block diagram showing an example of the configuration of the control system (swivel control system) of the upper swivel body 3 of the excavator according to the present embodiment. As shown in FIG. 4, the controller 30 includes a turning control unit 301 and a monitoring unit 302 as functional blocks related to the turning control system.

The swivel control unit 301 (an example of the first control unit) has a current detection value Is of the current sensor 21s, a detection value (speed detection value) ωs of the rotation speed of the resolver 22, and a pressure corresponding to the swivel operation of the upper swivel body 3. The swivel motor 21 is driven and controlled based on the pressure detection values P1s and P2s from the sensors 29 (pressure sensors 29-1, 29-2). The turning control unit 301 includes a command generation unit 3011 and a speed / torque feedback control unit (speed / torque FB control unit) 3012.

The pressure sensors 29-1 and 29-2 are used for the left turning operation (tilting operation of the lever 26A to the left) and the right turning operation (tilting operation of the lever 26A to the right), respectively. The corresponding pilot pressure detection values (pressure detection values P1s, P2s) are transmitted to the controller 30. That is, the pressure sensors 29-1 and 29-2 are examples of the operation amount detection unit that detects the operation amount (in the left-right direction) of the lever 26A that operates the upper swing body 3. Further, the current detection value Is of the current sensor 21s includes a plurality of detection values of the plurality of current sensors included.

The command generation unit 3011 is for driving and controlling the speed command C (to drive and control the turning electric motor 21) based on the pressure detection values P1s and P2s of the pressure sensors 29-1 and 29-2 received via the predetermined interface of the controller 30. Generate an example of the generated control command value). The speed command C is generated as, for example, a command signal indicating a ratio (percentage) to the turning speed (maximum turning speed ωmax) of the lever 26A at the full stroke. The command generation unit 3011 transmits the generated speed command C to the speed / torque FB control unit 3012.

The speed / torque FB control unit 3012 has the speed detection value ωs of the resolver 22 and the current detection value Is (corresponding torque of the turning motor 21) of the current sensor 21s in order to realize the turning speed corresponding to the speed command C. The speed feedback control and the torque feedback control of the turning electric motor 21 are performed based on the above. Specifically, the speed / torque FB control unit 3012 generates a torque command according to the difference between the turning speed ωc corresponding to the speed command C and the speed detection value ωs. Then, the speed / torque FB control unit 3012 receives a drive signal for driving the inverter 18B, for example, a PWM signal (Pulse Width Modulation), according to the difference between the generated torque command and the torque value corresponding to the current detection value Is. Generate a signal. The speed / torque FB control unit 3012 transmits a drive signal to the monitoring unit 302.

The monitoring unit 302 (an example of the second control unit) responds to a gate lock lever signal (an example of information corresponding to the operating state of the gate lock lever 32) from the gate lock lever SW34 received via a predetermined interface of the controller 30. Based on this, the abnormality related to the operation (swivel operation) of the upper swivel body 3 is monitored. For example, when the gate lock lever signal is OFF, the monitoring unit 302 detects an abnormality related to the turning operation (abnormality detection processing). Further, for example, when the monitoring unit 302 detects an abnormality related to the turning operation when the gate lock lever signal is OFF, or when a predetermined condition corresponding to the abnormality is satisfied, the operating state of the lever 26A ( The stop control of the upper swivel body 3 is performed regardless of the operating state of the swivel control unit 301). The "stop control of the upper swivel body 3" includes both a control for stopping (decelerating) the upper swivel body 3 during turning (deceleration control) and a control for maintaining the stopped state of the upper swivel body 3 (swivel lock control). .. That is, the monitoring unit 302 prevents the upper swing body 3 from turning regardless of whether the lever 26A is operated or not when the gate lock lever signal is OFF (that is, when the gate lock lever 32 is in the locked state). .. The monitoring unit 302 outputs a drive signal transmitted from the speed / torque FB control unit 3012 to the inverter 18B in a normal state, that is, in a situation where there is no abnormality related to the turning operation. On the other hand, the monitoring unit 302 realizes stop control of the upper swivel body 3 by prohibiting (not outputting) the output of the drive signal in a situation where there is an abnormality related to the swivel operation. Details of the processing by the monitoring unit 302 will be described later.

The stop control of the upper swing body 3 may be realized by operating the mechanical brake 23. Further, the monitoring unit 302 may prohibit the output of the drive signal when performing the turning lock control, and may perform control (so-called 0-speed control) in which the monitoring unit 302 generates the drive signal and maintains the stopped state.

[Processing of monitoring unit]
Next, the details of the monitoring process in the monitoring unit 302 will be described with reference to FIGS. 5 to 8.

First, FIG. 5 is a flowchart schematically showing an example of the first monitoring process by the monitoring unit 302. The process according to this flowchart is executed, for example, when the excavator is keyed on (when it is started) or when it is keyed off (when the operation is finished). Further, as will be described later in FIG. 7, the excavator may be executed during operation (between key-on and key-off).

Referring to FIG. 5, in step S102, the monitoring unit 302 determines whether or not the gate lock lever signal is OFF (that is, whether or not the gate lock lever 32 is in the locked state). Monitoring section 302, when the gate lock lever signal is OFF, the process proceeds to step S 1 04, when the gate lock lever signal is not OFF (is ON), skips step S104, S106, it terminates the current process To do.

In step S104, the monitoring unit 302 performs an abnormality detection process. For example, the monitoring unit 302 determines whether or not the output value of the monitoring target related to the turning operation is within the normal range, that is, whether or not it is within the range corresponding to the stopped state of the upper turning body 3. The “monitoring target related to the turning operation” is, for example, a current sensor 21s, a resolver 22, a command generation unit 3011, a pressure sensor 29, and the like. Then, when the output value of the monitoring target is not within the range corresponding to the stop information of the upper swivel body 3, the monitoring unit 302 may determine that there is an abnormality related to the swivel operation (abnormality determination). As described above, when the gate lock lever 32 is in the locked state, even if the excavator is not operated by the operator or the lever 26A is unintentionally touched, the operation device is operated by the gate lock switching valve 36. No pilot pressure is generated on the secondary side of 26. In particular, when the excavator is keyed on (when activated), the gate lock lever 32 is almost always in the locked state, and the excavator is not operated. Therefore, in such a situation, if the output value to be monitored is not within the range corresponding to the stopped state of the upper swivel body 3, it can be determined that there is an abnormality related to the swivel operation.

In step S106, the monitoring unit 302 prohibits (cuts off) the output of the drive signal for driving the turning electric motor 21 to the inverter 18B, that is, starts the turning lock control and ends the current process.

In the process shown in FIG. 5, the monitoring unit 302 performs turning lock control regardless of the result of the abnormality detection process, but only when it is determined as a result of the abnormality detection process that there is an abnormality related to the turning operation. Swivel lock control may be performed.

In this way, when the gate lock lever signal is OFF, that is, when the gate lock lever 32 is in the locked state, the monitoring unit 302 does not rotate the upper swivel body 3 regardless of whether or not the lever 26A is operated. To do. Specifically, when the gate lock lever signal is OFF, the monitoring unit 302 prohibits (cuts off) the output of the drive signal for driving the turning electric motor 21 to the inverter 18B, that is, performs turning lock control. Further, when the gate lock lever signal is OFF, the monitoring unit 302 performs an abnormality detection process of the monitoring target related to the turning operation. As a result, for example, before the operator detects an abnormality related to the turning operation that actually occurs, it is possible to detect an abnormality related to the turning operation or prohibit the turning operation in response to the abnormality. The safety of the excavator that electrically drives the body 3 can be further enhanced.

Subsequently, FIG. 6 is a flowchart schematically showing another example of the first monitoring process by the monitoring unit 302. Similar to FIG. 5, the process according to this flowchart is executed, for example, when the excavator is keyed on (at the time of activation) or at the time of key off (at the end of operation). Further, as will be described later in FIG. 8, the excavator may be executed during operation (between key-on and key-off).

As described below, the monitoring unit 302 has an abnormality related to the operation of the upper swing body 3 based on the gate lock lever signal, the speed detection value ωs, the current detection value Is, the pressure detection values P1s, P2s, and the speed command C. Is detected, and the stop control of the upper swing body 3 is performed.

The abnormality flags F1 to F4, which will be described later, are set to "0", which indicates that they are normal, as initial settings.

Referring to FIG. 6, in step S202, the monitoring unit 302 determines whether or not the gate lock lever signal is OFF (that is, whether or not the gate lock lever 32 is in the locked state). When the gate lock lever signal is OFF, the monitoring unit 302 proceeds to step S204, and when the gate lock lever signal is not OFF (ON), the monitoring unit 302 skips steps S204 to S224 and ends the current process.

In step S204, the monitoring unit 302 determines whether or not the current detection value Is is in the range corresponding to the stopped state of the upper swing body 3, that is, in the range equal to or less than the predetermined threshold value Isth. If the current detection value Is is not equal to or less than the predetermined threshold value Isth, the monitoring unit 302 proceeds to step S206, and if it is equal to or less than the predetermined threshold value Isth, the monitoring unit 302 skips step S206 and proceeds to step S208. More specifically, if at least one of the plurality of sensors included in the current sensor 21s does not satisfy the above condition, the monitoring unit 302 proceeds to step S206, and all the sensors included in the current sensor 21s satisfy the above condition. If satisfied, the process proceeds to step S208.

The predetermined threshold value Isth is very high enough to correspond to current 0 or so-called 0-speed control (for example, control that maintains the rotation speed of the turning motor 21 at zero even when an external force such as a gravity component due to inclination acts). Set as a small current value.

In step S206, the monitoring unit 302 determines that the current sensor 21s has an abnormality (current sensor abnormality), and sets the abnormality flag F1 indicating the presence or absence of the abnormality of the current sensor 21s to "1" indicating the abnormality. As described above, when the gate lock lever 32 is in the locked state, even if the excavator is not operated by the operator or the lever 26A is unintentionally touched, the operation device is operated by the gate lock switching valve 36. No pilot pressure is generated on the secondary side of 26. In particular, when the excavator is keyed on (when activated), the gate lock lever 32 is almost always in the locked state, and the excavator is not operated. Therefore, in such a situation, if the current detection value Is of the current sensor 21s is not within the range corresponding to the stopped state of the upper swing body 3, it can be determined that the current sensor 21s has an abnormality.

In step S208, the monitoring unit 302 determines whether or not the speed detection value ωs is in the range corresponding to the stopped state of the upper swing body 3, that is, in the range equal to or less than the predetermined threshold value ωsth. If the speed detection value ωs is not equal to or less than the predetermined threshold value ωsth, the monitoring unit 302 proceeds to step S210. If the speed detection value ωs is not equal to or less than the predetermined threshold value ωsth, the monitoring unit 302 skips step S210 and proceeds to step S212.

The predetermined threshold value ωsth is set as a rotation speed of 0 or a very small rotation speed value corresponding to so-called 0-speed control.

In step S210, the monitoring unit 302 determines that the resolver 22 has an abnormality (resolver abnormality), and sets the abnormality flag F2 indicating the presence or absence of the abnormality of the resolver 22 to "1" indicating the abnormality. This is for the same reason as the abnormality determination of the current sensor 21s in step S206.

In step S212, the monitoring unit 302 determines whether or not the pressure detection values P1s and P2s are both in the range corresponding to the stopped state of the upper swing body 3, that is, in the range equal to or less than the predetermined threshold value Psth. The monitoring unit 302 proceeds to step S214 when either one of the pressure detection values P1s and P2s is not equal to or less than the predetermined threshold value Psth, and skips step S214 when both the pressure detection values P1s and P2s are equal to or less than the predetermined threshold value Psth. , Step S216.

The predetermined threshold value Psth is set as a very small pressure value corresponding to the pilot pressure 0 (operation amount 0) due to the action of the gate lock switching valve 36.

In step S214, the monitoring unit 302 determines that at least one of the pressure sensors 29-1 and 29-2 has an abnormality (pressure sensor abnormality), and indicates the presence or absence of an abnormality in the pressure sensors 29-1 and 29-2. The abnormality flag F3 is set to "1" indicating an abnormality. This is for the same reason as the abnormality determination of the current sensor 21s in step S206.

In step S214, it may be determined whether or not there is an abnormality in each of the pressure sensors 29-1 and 29-2 according to the determination result in step S212.

In step S216, the monitoring unit 302 sets the abnormality flag F3 to "0" (that is, the pressure sensors 29-1 and 29-2 are normal) and the speed command C to the stopped state of the upper swing body 3. It is determined whether or not it is not in the corresponding range, that is, it is larger than the predetermined threshold value Cth. If the condition is satisfied, the monitoring unit 302 proceeds to step S218, and if the condition is not satisfied, the monitoring unit 302 skips step S218 and proceeds to step S220.

The predetermined threshold value Cth is set as a rotation speed of 0 or a very small value (percentage) corresponding to the so-called 0-speed control.

In step S218, the monitoring unit 302 determines that the command generation unit 3011 (that is, the software process that realizes the command generation unit 3011) has an abnormality (command generation unit abnormality), and determines whether or not there is an abnormality in the command generation unit 3011. The abnormality flag F4 to indicate is set to "1" indicating an abnormality. As described above, when the gate lock lever 32 is in the locked state, even if the excavator is not operated by the operator or the lever 26A is unintentionally touched, the operation device is operated by the gate lock switching valve 36. No pilot pressure is generated on the secondary side of 26. In particular, when the excavator is keyed on (when activated), the gate lock lever 32 is almost always in the locked state, and the excavator is not operated. Therefore, in such a situation, although the pressure detection values P1s and P2s indicate normal values (corresponding to the pilot pressure 0), the speed command C generated by the command generation unit 3011 turns upward. If it is not within the range corresponding to the stopped state of the body 3, it can be determined that the command generation unit 3011 has an abnormality.

In step S220, the monitoring unit 302 determines whether any one of the values of the abnormality flags F1 to F4 is "1", that is, the current sensor 21s, the resolver 22, the pressure sensors 29-1, 29-2, and the command. It is determined whether or not at least one of the generation units 3011 has an abnormality. The monitoring unit 302 proceeds to step S222 when any one of the values of the abnormality flags F1 to F4 is "1", and steps S222 and S224 when all the values of the abnormality flags F1 to F4 are "0". To skip this process and end this process.

In step S222, the monitoring unit 302 prohibits (cuts off) the output of the drive signal for driving the turning electric motor 21 to the inverter 18B, that is, starts the turning lock control.

In step S224, the monitoring unit 302 displays an abnormality occurrence notification (warning) and an abnormality location on a monitor (not shown) in the cabin 10 communicably connected to the controller 30, and ends the current process. .. As a result, the operator and the serviceman can recognize the occurrence of the abnormality and the abnormal portion and take appropriate measures such as repair.

The order of determining the presence or absence of an abnormality related to the monitoring target in the process shown in FIG. 6 may be arbitrary. However, the process of determining the presence or absence of an abnormality in the command generation unit 3011 (step S216) needs to be performed after the process of determining the presence or absence of an abnormality in the pressure sensors 29-1 and 29-2 (step S212). Further, in the process shown in FIG. 6, as abnormalities related to the turning operation, the resolver 22 (speed detection value ωs), the current sensor 21s (current detection value Is), and the pressure sensors 29-1, 29-2 (pressure detection values P1s, P2s). ), And the command generation unit 3011 (speed command C) determines the presence or absence of an abnormality in all the monitoring targets, but the mode may be in which the presence or absence of an abnormality in some monitoring targets is determined. That is, the monitoring unit 302 detects an abnormality related to the turning operation based on the gate lock lever signal and at least one of the speed detection value ωs, the current detection value Is, the pressure detection values P1s and P2s, and the speed command C. It may be. However, when only the gate lock lever signal and the speed command C are used, it is possible to detect an abnormality related to the turning operation, but it is not possible to identify the abnormal part. Further, in the process shown in FIG. 6, both the abnormality detection and the swivel lock control are performed, but the mode may be a mode in which only the abnormality detection is performed or a mode in which only the swivel lock control is performed. In the case of performing only the turning lock control, the monitoring unit 302 satisfies the turning lock control (swivel lock control) when any one of the conditions for determining that there is an abnormality is satisfied in the processing of steps S204, S208, S212, and S216 described later. The process of step S222) is performed.

In this way, the monitoring unit 302 detects an abnormality related to the turning operation based on the gate lock lever signal and at least one of the speed detection value ωs, the current detection value Is, the pressure detection values P1s and P2s, and the speed command C. Perform or perform swivel lock control. Specifically, in the monitoring unit 302, when the gate lock lever signal represents the locked state of the gate lock lever 32, the speed detection value ωs, the current detection value Is, the pressure detection values P1s, P2s, and If at least one of the speed commands C is not within the range corresponding to the stopped state of the upper swivel body 3, it is determined that there is an abnormality related to the swivel operation, or the swivel lock control is performed. As a result, for example, before the operator detects an abnormality related to the turning operation that actually occurs, it is possible to detect an abnormality related to the turning operation or prohibit the turning operation in response to the abnormality. The safety of the excavator that electrically drives the body 3 can be further enhanced.

Subsequently, FIG. 7 is a flowchart schematically showing an example of the second monitoring process by the monitoring unit 302. The process according to this flowchart may be executed when the gate lock lever signal changes from ON to OFF during the operation of the excavator (between key-on and key-off).

With reference to FIG. 7, in step S302, the monitoring unit 302 determines whether or not the gate lock lever signal is OFF (that is, whether or not the gate lock lever 32 is in the locked state). When the gate lock lever signal is OFF, the monitoring unit 302 proceeds to step S304, and when the gate lock lever signal is not OFF (ON), the monitoring unit 302 skips the processes of steps S304 to S310 and ends the current process. To do.

In step S304, the monitoring unit 302 determines whether or not the upper swivel body 3 is swiveling. The monitoring unit 302 may comprehensively determine whether or not the vehicle is turning by using a plurality of the speed detection value ωs, the current detection value Is, the pressure detection values P1s and P2s, and the speed command C. As a result, even if an abnormality has occurred in any of the current sensor 21s, the resolver 22, the pressure sensors 29-1, 29-2, and the command generation unit 3011, it is possible to more accurately determine whether or not the vehicle is turning. Further, the monitoring unit 302 may use any one (typically, the speed detection value ωs) to determine whether or not the vehicle is turning. The monitoring unit 302 proceeds to step S306 when the upper swing body 3 is turning, and proceeds to step S308 when the upper swing body 3 is not turning.

In step S306, the monitoring unit 302 performs a process of urgently stopping the upper swing body 3 (emergency stop process).

On the other hand, when it is determined in step S304 that the upper swivel body 3 is not swiveling, in steps S308 and S310, the monitoring unit 302 performs the abnormality detection process and the swivel lock as in FIG. 5 (steps S104 and S106). Control is performed and the current process is terminated.

In this way, when the gate lock lever signal is turned from ON to OFF, that is, when the gate lock lever 32 transitions from the unlocked state to the locked state when the upper swivel body 3 is swiveled, the monitoring unit 302 operates the swivel control unit 301. Regardless of, the upper swivel body 3 is urgently stopped. As a result, safety can be further enhanced.

Subsequently, FIG. 8 is a flowchart schematically showing another example of the second monitoring process by the monitoring unit 302. Similar to FIG. 7, the process according to this flowchart may be executed when the gate lock lever signal changes from ON to OFF during the operation of the excavator (between key-on and key-off).

Referring to FIG. 8, in step S402, the monitoring unit 302 determines whether or not the gate lock lever signal is OFF (that is, whether or not the gate lock lever 32 is in the locked state). The monitoring unit 302 proceeds to step S404 when the gate lock lever signal is OFF, skips the processes of steps S404 to S412 when the gate lock lever signal is not OFF (ON), and ends the current process. To do.

In step S404, the monitoring unit 302 determines whether or not the upper swivel body 3 is swiveling. As described above, the monitoring unit 302 uses a plurality of the speed detection value ωs, the current detection value Is, the pressure detection values P1s, P2s, and the speed command C to comprehensively determine whether or not the vehicle is turning. You can do it. Further, as described above, the monitoring unit 302 may use any one (typically, the speed detection value ωs) to determine whether or not the vehicle is turning. The monitoring unit 302 proceeds to step S406 when the upper swing body 3 is turning, and proceeds to step S412 when the upper swing body 3 is not turning.

In step S406, the monitoring unit 302 cuts off (invalidates) the drive signal from the command generation unit 3011, generates a drive signal by itself, and controls the upper swing body 3 to decelerate and make an emergency stop (deceleration). control). This is because when the gate lock lever 32 is locked during the turning of the upper swing body 3, it can be estimated that the operator has detected some abnormality in the turning operation and operated the gate lock lever 32.

In step S408, the monitoring unit 302 determines whether or not the upper swing body 3 has stopped. Similar to step S404, the monitoring unit 302 uses a plurality of the speed detection value ωs, the current detection value Is, the pressure detection values P1s, P2s, and the speed command C to determine whether or not the vehicle is turning comprehensively. It may be determined, or one of them (typically, the speed detection value ωs) may be used to determine whether or not the vehicle is turning. When the upper swing body 3 is stopped, the monitoring unit 302 proceeds to step S410, and when the upper swing body 3 is not stopped, the monitoring unit 302 repeats the processes of steps S406 and S408 until it stops.

In step S410, the monitoring unit 302 prohibits (cuts off) the output of the drive signal for driving the turning electric motor 21 to the inverter 18B, that is, starts the turning lock control and ends the current process. As a result, the turning motion of the upper swinging body 3 can be quickly prohibited in response to the abnormality related to the turning motion detected by the operator.

Instead of the process of step S410, the process may shift to the first monitoring process shown in FIG. As a result, the swivel lock control can be started after confirming that the abnormality detected by the operator is actually occurring (that is, the swivel operation of the upper swivel body 3 can be prohibited).

On the other hand, if it is determined in step S404 that the upper swivel body 3 is not swiveling, in step S412, the monitoring unit 302 shifts to the first monitoring process shown in FIG. 6 and ends this process. To do. As a result, for example, during the operation of the excavator, every time the operator gets off the cabin 10, it is possible to determine whether or not there is an abnormality related to the turning operation, so that it is possible to increase the chance of detecting the abnormality and shorten the time lag from the occurrence of the abnormality to the detection. Therefore, the safety can be further improved.

In this way, when the gate lock lever signal is turned from ON to OFF, that is, when the gate lock lever 32 transitions from the unlocked state to the locked state when the upper swivel body 3 is swiveled, the monitoring unit 302 operates the swivel control unit 301. Regardless of, the control for decelerating the turning electric motor 21 is performed. As a result, when the operator senses some abnormality in the turning operation and operates the gate lock lever 32, the turning upper swing body 3 can be urgently stopped, and the safety can be further improved. ..

[Other examples of configuration]
Next, another example of the shovel configuration according to the present embodiment will be described with reference to FIGS. 9 and 10. In this example, unlike the above-mentioned example (FIGS. 2 and 4), the function (driver function) of the speed / torque FB control unit 3012 is built in the inverter 18B, and the function of the monitoring unit 302 monitors the outside of the controller 30. It is realized as a device 38. Hereinafter, the same configurations as those of the above-mentioned example will be designated by the same reference numerals, and different parts will be mainly described.

FIG. 9 is a block diagram showing another example of the configuration centered on the drive system of the excavator according to the present embodiment. FIG. 10 is a functional block diagram showing another example of the configuration of the turning control system according to the present embodiment.

In FIG. 9, the mechanical power system is shown by a double line, the high-pressure hydraulic line is shown by a thick solid line, the pilot line is shown by a broken line, and the electric drive / control system is shown by a thin solid line. Further, since the appearance (side view) of the excavator and the configuration of the power storage system 120 are shown in FIGS. 1 and 3 as in the above-mentioned example, the description thereof will be omitted.

The swivel control unit 301 (another example of the first control unit) includes a command generation unit 3011 included in the controller 30 and a speed / torque FB control unit 3012 built in the inverter 18B.

The command generation unit 3011 transmits the speed command C to the inverter 18B and also to the monitoring device 38.

The inverter 18B includes an inverter circuit 181B, a communication line 182B, a cutoff unit 183B, and a speed / torque FB control unit 3012.

The inverter circuit 181B operates based on a drive signal (PWM signal) transmitted from the speed / torque FB control unit 3012 through the communication line 182B. Specifically, the inverter circuit 181B converts the electric power supplied from the power storage system 120 into three-phase AC power for driving the swirling electric motor 21 based on the drive signal, or regenerates the electric power from the swirling electric motor 21. Is converted into DC power and supplied to the power storage system 120.

The cutoff unit 183B is provided on the communication line 182B that communicably connects the inverter circuit 181B and the speed / torque FB control unit 3012, and can switch between the connection and the cutoff of the communication line 182B. The cutoff unit 183B cuts off the communication line 182B in response to a cutoff signal received from the monitoring device 38 through a predetermined interface of the inverter 18B. The blocking unit 183B is, for example, a mechanical switch or a semiconductor switch (switching element).

The speed / torque FB control unit 3012 is, for example, a driver IC (Integrated Circuit) built in the inverter 18B. The speed / torque FB control unit 3012 distinguishes the speed command C received from the controller 30 (command generation unit 3011) through the predetermined interface of the inverter 18B (hereinafter, the speed command C generated and output by the command generation unit 3011). , "Received speed command Crcv") to generate a drive signal. That is, in order to realize the turning speed corresponding to the reception speed command Crcv, the speed / torque FB control unit 3012 has the speed detection value ωs of the resolver 22 and the current detection value Is (corresponding to the current detection value Is) of the current sensor 21s. The speed feedback control and the torque feedback control of the turning electric motor 21 are performed based on the torque). The speed / torque FB control unit 3012 transmits the generated drive signal to the inverter circuit 181B through the communication line 182B.

The monitoring device 38 (another example of the second control unit) is provided separately from the inverter 18B and the controller 30, and includes the current sensor 21s, the resolver 22, the pressure sensors 29-1, 29-2, the gate lock lever SW34, and the inverter 18B. , And communicably connected to the controller 30. The monitoring device 38 monitors an abnormality related to the turning operation based on the gate lock lever signal from the gate lock lever SW34. The monitoring device 38 detects, for example, an abnormality related to the turning operation. Further, when the monitoring device 38 detects, for example, an abnormality related to the turning operation, or when a predetermined condition corresponding to the abnormality is satisfied, the monitoring device 38 is independent of the operating state of the lever 26A (operating state of the turning control unit 301). The stop control of the upper swing body 3 is performed. The monitoring device 38 realizes stop control of the upper swivel body 3 by transmitting a shutoff signal to the shutoff unit 183 and shutting off the communication line 182B in a situation where there is an abnormality related to the swivel operation. Details of the processing by the monitoring device 38 will be described later.

The stop control of the upper swing body 3 may be realized by operating the mechanical brake 23. Further, the monitoring device 38 may prohibit the output of the drive signal when performing the turning lock control, and may perform control (so-called 0-speed control) in which the monitoring device 38 generates the drive signal and maintains the stopped state. Further, by omitting the cutoff unit 183B and transmitting a command to the speed / torque FB control unit 3012 to prohibit the output of the drive signal, the monitoring device 38 realizes the stop control of the upper swing body 3. May be good.

[Processing of monitoring device 38]
Next, the details of the processing in the monitoring device 38 will be described with reference to FIG.

FIG. 11 is a flowchart schematically showing an example of the first monitoring process by the monitoring device 38. The process according to this flowchart is executed, for example, when the excavator is keyed on (when it is started) or when it is keyed off (when the operation is finished). It may also be executed while the excavator is in operation (between key-on and key-off) (see FIG. 8 cited later).

Similar to the monitoring unit 302 according to the above-described example, the monitoring device 38 includes a gate lock lever signal, a speed detection value ωs, a current detection value Is, pressure detection values P1s, P2s, and a speed command C, as described below. Based on the above, the abnormality related to the operation of the upper swivel body 3 is detected, and the stop control of the upper swivel body 3 is performed.

In the process shown in FIG. 11, as abnormalities related to the turning operation, the speed detection value ωs, the current detection value Is, the pressure detection values P1s, P2s, the speed command C, the controller 30 (command generation unit 3011), and the inverter 18B (speed). -Although the abnormality related to all the communication states with the torque FB control unit 3012) is detected, the mode may be such that an abnormality related to at least one is detected. That is, the monitoring device 38 has an abnormality related to the turning operation based on the gate lock lever signal and at least one of the speed detection value ωs, the current detection value Is, the pressure detection values P1s, P2s, the speed command C, and the reception speed command Crcv. It may be an aspect of detecting the above. However, for example, when only the gate lock signal and the speed command C or the reception speed command Crcv are used, it is possible to detect an abnormality related to the turning operation, but it is not possible to identify the abnormal part. Further, in the process shown in FIG. 5, both the abnormality detection and the swivel lock control are performed, but the mode may be a mode in which only the abnormality detection is performed or a mode in which only the swivel lock control is performed. In the embodiment in which only the turning lock control is performed, the monitoring device 38 satisfies any one of the conditions for determining that there is an abnormality in the processing of steps S504, S508, 312, S516, and S520 described later, and then the turning lock is performed. Control (processing in step S222) is performed. Further, the abnormality flags F1 to F5, which will be described later, are set to "0" indicating that they are normal as initial settings.

Since the processing of steps S502 to S518 in this flowchart is the same as the processing of steps S202 to S218 shown in FIG. 5, the description thereof will be omitted.

In step S520, in the monitoring device 38, the abnormality flags F3 and F4 are "0" (that is, the pressure sensors 29-1, 29-2 and the command generation unit 3011 are normal), and the reception speed command Crcv is on the upper side. It is determined whether or not the swivel body 3 is not in the range corresponding to the stopped state, that is, is larger than the predetermined threshold value Cth. When the condition is satisfied, the monitoring device 38 proceeds to step S522, and when the condition is not satisfied, the monitoring device 38 skips step S522 and proceeds to step S524.

In this step, the monitoring device 38 may determine whether or not the speed command C and the reception speed command Crcv are the same. When this process is adopted, if the speed command C and the reception speed command Crcv are not the same, the process proceeds to step S522, and if the speed command C and the reception speed command Crcv are the same, step S522 is skipped and step S524 is performed. Proceed to.

In step S522, the monitoring device 38 determines that there is an abnormality in the communication state (communication abnormality) between the controller 30 (command generation unit 3011) and the inverter 18B (speed / torque FB control unit 3012), and determines a communication abnormality. The abnormality flag F5 to indicate is set to "1" indicating an abnormality. As described above, when the gate lock lever 32 is in the locked state, even if the excavator is not operated by the operator or the lever 26A is unintentionally touched, the operation device is operated by the gate lock switching valve 36. No pilot pressure is generated on the secondary side of 26. In particular, when the excavator is keyed on (when activated), the gate lock lever 32 is almost always in the locked state, and the excavator is not operated. Therefore, in such a situation, the pressure detection values P1s and P2s show normal values (corresponding to the pilot pressure 0), and the speed command C generated by the command generation unit 3011 also shows normal values. If the reception speed command Crcv is not within the range corresponding to the stopped state of the upper swing body 3, it can be determined that there is a communication abnormality.

In step S524, the monitoring device 38 determines whether any one of the values of the abnormality flags F1 to F5 is "1", that is, the current sensor 21s, the resolver 22, the pressure sensors 29-1, 29-2, and the command. It is determined whether or not there is an abnormality in at least one of the communication states between the generation unit 3011, the controller 30, and the inverter 18B. The monitoring device 38 proceeds to step S526 when any one of the values of the abnormality flags F1 to F5 is "1", and steps S526 and S528 when all the values of the abnormality flags F1 to F5 are "0". To skip this process and end this process.

In step S526, the monitoring device 38 transmits a cutoff signal to the inverter 18B (cutoff unit 183B), that is, starts turning lock control.

In step S526, the monitoring device 38 causes a monitor (not shown) in the cabin 10 communicably connected to display an abnormality occurrence notification (warning) and an abnormality location, and ends the current process. As a result, the operator and the serviceman can recognize the occurrence of the abnormality and the abnormal portion and take appropriate measures such as repair.

As described above, in the configuration according to this example (the configuration in which the command generation unit 3011 is included in the controller 30 and the speed / torque FB control unit 3012 is included in the inverter 18B), the monitoring device 38 detects the gate lock signal and the pressure. Based on the values P1s and P2s, the speed command C, and the reception speed command Crcv, it is possible to detect a communication abnormality between the controller 30 (command generation unit 3011) and the inverter 18B (speed / torque FB control unit 3012).

Further, the monitoring device 38 performs the second monitoring process in the same manner as the monitoring unit 302 according to the above-described example. Since the second monitoring process by the monitoring device 38 is represented by FIG. 8 as in the above-mentioned example, the description thereof will be omitted.

Although the embodiments for carrying out the present invention have been described in detail above, the present invention is not limited to such specific embodiments, and various aspects are within the scope of the gist of the present invention described in the claims. Can be transformed / changed.

1 Lower traveling body 1A, 1B Traveling hydraulic motor 2 Swivel mechanism 3 Upper revolving body (swivel body)
4 Boom 5 Arm 6 Bucket 7 Boom Cylinder 8 Arm Cylinder 9 Bucket Cylinder 10 Cabin 11 Engine 12 Motor Generator 13 Decelerator 14 Main Pump 15 Pilot Pump 16 High Pressure Hydraulic Line 17 Control Valve 18A Inverter 18B Inverter (Drive)
19 Capacitor 21 Swivel motor (motor)
21s current sensor (current detector)
22 Resolver (speed detector)
23 Mechanical brake 24 Swivel reducer 25 Pilot line 26 Operating device 26A, 26B Lever 26C Pedal 27,28 Hydraulic line 29,29-1,29-2 Pressure sensor (operation amount detector)
30 Controller 32 Gate lock lever 34 Gate lock lever switch 36 Gate lock switching valve 38 Monitoring device 181B Inverter circuit (drive device)
182B communication line 183B cutoff unit 301 turning control unit (first control unit)
302 Monitoring unit (second control unit)
3011 Command generator 3012 Speed / torque feedback control unit

Claims (9)

With a swivel body
The electric motor that drives the swivel body and
A speed detection unit that detects the rotation speed of the electric motor,
A current detection unit that detects the current of the electric motor, and
An operation amount detection unit that detects the operation amount of the operation lever that operates the swivel body, and
A first control unit that controls the drive of the electric motor based on the detection value of the speed detection unit, the detection value of the current detection unit, and the detection value of the operation amount detection unit .
Driving information corresponding to the operation state of the Gate thickens Clever, the detected value of the speed detection unit, the detection value of the current detection unit, the detection value of the operation amount detecting unit, and the electric motor that is generated by the first control unit A second control unit that detects an abnormality related to the operation of the swivel body or controls the stop of the swivel body based on at least one of the control command values for control is provided .
Shi Yoberu. In the second control unit, when the information indicates the locked state of the gate lock lever, the detection value of the speed detection unit, the detection value of the current detection unit, the detection value of the operation amount detection unit, Alternatively, when the control command value is not within the range corresponding to the stopped state of the swivel body, it is determined that there is the abnormality, or the stop control of the swivel body is performed.
The excavator according to claim 1. The second control unit detects the speed when the information indicates the locked state of the gate lock lever and the detection value of the speed detection unit is not within the range corresponding to the stopped state of the swivel body. Judge that there is something wrong with the part,
The excavator according to claim 2. The second control unit detects the current when the information indicates the locked state of the gate lock lever and the detection value of the current detection unit is not within the range corresponding to the stopped state of the swivel body. Judge that there is something wrong with the part,
The excavator according to claim 2 or 3. The second control unit operates the operation when the information indicates the locked state of the gate lock lever and the detection value of the operation amount detection unit is not within the range corresponding to the stopped state of the swivel body. Judge that there is an abnormality in the amount detector,
The excavator according to any one of claims 2 to 4. In the second control unit, the information indicates a locked state of the gate lock lever, the detection value of the operation amount detection unit is in a range corresponding to the stopped state of the swivel body, and the second control unit is described. If the control command value is not within the range corresponding to the stopped state of the swivel body, it is determined that there is an abnormality in the first control unit.
The excavator according to any one of claims 2 to 5. When the shovel is keyed on, the second control unit includes information corresponding to the operating state of the gate lock lever, a detection value of the speed detection unit, a detection value of the current detection unit, and a detection value of the operation amount detection unit. And, based on at least one of the control command values, the abnormality related to the operation of the swivel body is detected, or the stop control of the swivel body is performed.
The excavator according to any one of claims 1 to 6. When the information changes from the unlocked state of the gate lock lever to the locked state when the swivel body is swiveled, the second control unit decelerates the electric motor regardless of the operation of the first control unit. Control to make
The excavator according to any one of claims 1 to 7. A drive device for driving the electric motor is provided.
The first control unit drives and controls the electric motor by outputting the control command value to the drive device.
The second control unit controls the stop of the swivel body by blocking the output of the drive command based on the control command value to the drive device.
The excavator according to any one of claims 1 to 8.

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