JP5511316B2 - Excavator swivel control device - Google Patents

Description

  The present invention relates to a turning control device for a construction machine, and in particular, by giving an acceleration limit to a turning speed command, the shock at start-up is reduced, and the acceleration restriction is switched in multiple stages to improve work efficiency. The present invention relates to a turning control device for a construction machine that can suppress a decrease.

  2. Description of the Related Art Conventionally, for example, the following swing control device for an electric swing type work machine is known. This prior art controls an electric motor that drives an upper swing body of a shovel as a work machine to rotate, a turning operation lever that issues a turning command, and a rotational speed of the motor to a target speed corresponding to an operation amount of the turning operation lever. A turning control unit, and the turning control unit has turning acceleration setting means operated by an operator, and controls the speed of the electric motor toward the target speed with the acceleration set by the turning acceleration setting means. It is configured. The operator can set and change the turning acceleration according to the operation command in the turning acceleration setting means at the timing and magnitude desired by the operator. For this reason, for example, at the time of loading operation, the vehicle can be turned with an optimum acceleration according to the distance between two points, the required turn time desired by the operator, the operator's preference, and the like (for example, see Patent Document 1).

  As another conventional technique, for example, the following arm drive control device for a construction machine is known. This prior art is an arm drive control device in which an electric motor is used as power for moving an arm of a shovel car, and the rotation of the electric motor is controlled by an inverter. The acceleration / deceleration determination processing unit that determines the acceleration state or deceleration state from the amount of change of the value and its positive / negative polarity, and the acceleration state time constant and the deceleration state time constant are set separately, and the acceleration / deceleration determination A selection unit that selects the time constant for acceleration state or the time constant for deceleration state according to a determination signal of the processing unit, and is configured to output the selected time constant signal to the filter unit in the inverter. ing. The response speed at the time of acceleration and deceleration of the arm turning speed can be set separately to improve workability and safety (for example, see Patent Document 2).

JP 2009-68197 A JP 2009-68245 A

  In the prior art described in Patent Document 1, the turning acceleration is set and changed at the timing and magnitude desired by the operator at the operator's intention, and the turning speed command (output) has an acceleration limit. This is different from the technique in which the acceleration limitation is switched in multiple stages.

  In the prior art described in Patent Document 2, the response speed at the time of acceleration and deceleration of the arm turning speed can be set separately, and the turning speed command (output) is set in the same manner as described above. This is different from the technique in which the acceleration limitation is provided and the acceleration limitation is switched in multiple stages.

  Therefore, by limiting the acceleration to the turning speed command, the shock due to backlash during startup is reduced, the cab vibration during acceleration / deceleration is suppressed, the ride comfort is improved, and the useful life of the turning mechanism is increased. By increasing the acceleration limit in the middle and increasing the acceleration, the turning operation is prevented from slowing down, reducing the work efficiency and reducing the acceleration near the maximum speed to eliminate the feeling of stalling By reducing the absolute value of the acceleration and switching to increase the acceleration on the way, the flow of turning is reduced and the acceleration is reduced to a small absolute value just before stopping, so that the shock and return of stopping increase. The technical problem which should be solved in order to eliminate arises, and this invention aims at solving this problem.

The present invention has been proposed to achieve the above object, and the invention according to claim 1
In the excavator turning control device in which the speed of the turning of the turning body mounted with the cab is controlled by an electric motor,
The speed command of the electric motor of the turning, and having a control unit intends row by the speed command of the turning generated in response to the operation amount of the operating lever operated by an operator,
The control means includes
An acceleration processing system that selects a speed increment corresponding to the speed command from a plurality of speed increments in an acceleration state and switches to multiple stages, and a speed increment corresponding to the speed command from a plurality of speed increments in a deceleration state Built-in deceleration processing system to switch,
A shovel turning control device is provided in which the selected speed increment is added to or subtracted from the speed increment to output a speed command output .

  According to this configuration, the electric motor is more responsive to the speed command than the hydraulic motor. In such a rotating body controlled by an electric motor, the acceleration speed is restricted in multiple stages and the shock at the time of acceleration / deceleration is reduced. In addition, a decrease in work efficiency can be suppressed by switching to multiple stages so that the acceleration is reduced at the time of startup and then the acceleration is increased appropriately.

According to a second aspect of the present invention, there is provided the excavator turning control device according to the first aspect , wherein the limitation of the acceleration in the speed command is switched by a speed command output from the control means.

  According to this configuration, a plurality of acceleration / deceleration areas are set in the control means, and an acceleration to be limited for each of the acceleration / deceleration areas of the plurality of stages is set in advance. The acceleration to be limited is switched depending on which stage the speed command output from the control means corresponds to the speed command output of the acceleration / deceleration region.

According to a third aspect of the present invention, there is provided the excavator turning control device according to the first aspect , wherein the limitation of the acceleration in the speed command is switched by the actual turning speed of the turning body.

  According to this configuration, as described above, a plurality of acceleration / deceleration areas are set in the control means, and accelerations to be limited for each of the plurality of acceleration / deceleration areas are set in advance. When the speed command output from the control means and the actual turning speed of the turning body are equal, the actual turning speed of the turning body, that is, the speed command output from the control means corresponds to the speed command output in any acceleration / deceleration region. Depending on how the acceleration to be limited is switched.

According to a fourth aspect of the present invention, there is provided the excavator turning control device according to the first, second or third aspect, wherein hysteresis is given to switching of acceleration limitation in the speed command.

  According to this configuration, the amount of change in acceleration per unit time at the time of switching is suppressed to be small, and shocks and the like during acceleration / deceleration are further reduced.

  According to the first aspect of the present invention, the acceleration limitation is switched in multiple stages, so that the shock during acceleration / deceleration is reduced, the vibration of the cab is suppressed, the ride comfort is improved, and the service life of the turning mechanism is improved. Can be increased. In addition, it is possible to prevent the turning operation from being excessively slow and suppress a decrease in work efficiency, and it is possible to eliminate the feeling of stall by reducing the acceleration near the maximum speed. Furthermore, at the beginning of deceleration, the flow of turning can be reduced by switching the absolute value of the acceleration to be smaller and the acceleration to be increased in the middle, and the acceleration can be stopped by making the acceleration a small value just before stopping. There is an advantage that it is possible to eliminate an increase in shock and tremor.

  The invention described in claim 2 has an advantage that the acceleration to be limited can be switched reliably and easily in addition to the effect of the invention described in claim 1.

  In addition to the effect of the invention of the first aspect, the invention described in claim 3 further switches the acceleration to be limited when the speed command output from the control means and the actual turning speed of the turning body are equal. There is an advantage that can be.

  The invention according to claim 4 is advantageous in that the amount of change in acceleration per unit time at the time of switching can be kept small, and shocks and the like during acceleration / deceleration can be further reduced.

FIG. 1 shows a turning control device for a construction machine according to an embodiment of the present invention.
The block diagram of a controller. The figure which shows the example of a waveform of the speed command output by which the acceleration restriction | limiting was switched in multiple steps at the time of acceleration / deceleration control of a turning body. The flowchart for demonstrating the example of acceleration / deceleration control of the turning body by a controller. It is a figure for demonstrating the basic speed command output accompanying a speed command input, (a) is a wave form diagram which shows the example of speed command input by the operation lever operated stepwise, (b) has many acceleration restrictions. The wave form diagram which shows the example of the speed command output switched to the step.

In the present invention, by limiting the acceleration to the speed command for turning, the shock due to backlash at the time of starting is reduced, the vibration of the cab at the time of acceleration / deceleration is suppressed, the ride comfort is improved, and the durability of the turning mechanism is improved. By increasing the life span and switching the acceleration limit in the middle to increase the acceleration, the turning work is prevented from slowing down, reducing the work efficiency, and reducing the acceleration near the maximum speed to eliminate the feeling of stall and slowing down First, the absolute value of acceleration is reduced and switching is performed to increase acceleration in the middle to reduce the flow of turning, and just before stopping, reducing the acceleration to a small absolute value increases the shock and tremor of stopping. to achieve the objective of eliminating the, the excavator of the turning of the turning body cab is mounted to the speed control in an electric motor In times control device, the speed command for the electric motor of the turning is carried out by the speed command generated pivot in response to the operation amount of the operation lever operated by the operator, and, the speed instruction, the limit acceleration This was realized by providing a control means for switching to multiple stages.

  A preferred embodiment of the present invention will be described below with reference to FIGS. First, a basic speed command output example in the present embodiment will be described with reference to FIGS. FIG. 4A shows a waveform example of a speed command input when the operation lever is operated stepwise, and the controller described later executes a required process based on such speed command input. Thus, basically, a speed command output in which the acceleration limitation is switched in multiple stages as shown in FIG.

  That is, the controller outputs each speed command that accelerates at an acceleration 1 in the section 1a from the start to the speed a, accelerates at an acceleration 2 in the section 2a up to the speed b, and accelerates at an acceleration 3 in the section 3a up to the maximum speed. To do. On the other hand, at the time of deceleration, each speed command that accelerates at the acceleration 4 in the section 4a from the maximum speed to the speed d, decelerates at the acceleration 5 in the section 5a up to the speed e, and decelerates at the acceleration 6 in the section 6a until the stop is output. To do. As described above, in the control of the rotating body by the electric motor having a better response to the speed command than the hydraulic motor, the speed command output is limited in acceleration and the acceleration limit is switched in multiple stages, so In addition to reducing shocks, it works to reduce the work efficiency and other effects.

  Next, the configuration of the controller 11 as a control unit will be described with reference to FIGS. 1 and 2. The controller 11 is provided with an input port 13 for inputting a speed command by operating the operation lever 12 and an output port 14 for outputting a speed command to the electric motor (not shown). There are three built-in processing systems: an acceleration processing system 15A for processing signals during acceleration, a deceleration processing system 15B for processing signals during deceleration, and an acceleration / deceleration system 15C when there is no acceleration / deceleration.

In the acceleration processing system 15A, an acceleration processing unit 16 is connected to the input port 13 via a switch a ₁ that is turned on in an acceleration state, and the acceleration processing unit 16 is turned on in an acceleration state as described above. ₂ to the output port 14. As shown in the waveform diagram of FIG. 2, the acceleration processing unit 16 receives a speed increment (acceleration) 1 through a switch a ₃ that turns on in the first stage acceleration region, and in the second stage acceleration region. A speed increment input line 17 for inputting a speed increment 2 is connected via a switch a ₄ which turns on.

The deceleration processing system 15B is the input port 13, the deceleration processing part 18 is connected via a switch a ₅ to turn ON when the deceleration state, the switch a of deceleration processing unit 18 turns ON during deceleration state as in the ₆ to the output port 14. As shown in the waveform diagram of FIG. 2, a speed increment (acceleration) 4 is input to the deceleration processing unit 18 via a switch a ₇ that turns on in the second-stage deceleration area, and in the first-stage deceleration area. A speed increment input line 19 for inputting a speed increment 3 is connected via a switch a ₈ which turns on.

The acceleration no deceleration system 15C, since the speed command input is directly used as the speed command output, between the input port 13 and output port 14, only the switch a ₉ to turn on the on-time without acceleration or deceleration is connected. In addition to the acceleration processing system 15A, the deceleration processing system 15B, and the non-acceleration / deceleration system 15C, the controller 11 incorporates a control processing system (not shown) necessary for executing the turning control of this embodiment.

Next, the control action of the swivel body by the controller 11 configured as described above will be described with reference to the flowchart of FIG. 3 and FIGS. 1 and 2. When a speed command is input to the controller 11 by the operation of the operation lever 12 and the turning drive of the revolving structure is started, it is first determined from this speed command input whether or not the vehicle is in an acceleration state in step S1. The acceleration state is determined by determining that the difference between the current speed command input and the previous speed command input (current speed command input−previous speed command input) is a positive acceleration state. When the acceleration state is determined (Yes in step S1), the switches a ₁ and a ₂ in the controller 11 are turned on, and the magnitude of the speed command input and the current speed (actual turning speed) are compared in step S2. When the speed command input is larger than the current speed (speed command input> current speed) (Yes in step S2), the current speed and the speed command output are compared in magnitude in step S3.

  If the current speed is greater than the speed command output in step S3 (current speed> speed command output) (Yes in step S3), the speed command output initial value is set to the current speed in step S4, and the speed command output in step S5. Is determined to be less than or equal to the speed command output in the second stage acceleration region (speed command output ≦ second stage acceleration region). If the speed command input is smaller than or equal to the current speed in step S2 (speed command input ≦ current speed) (No in step S2), and if the current speed is smaller than the speed command output in step S3, or If equal (current speed ≦ speed command output) (No in step S3), it is determined in step S5 whether or not the speed command output is equal to or lower than the speed command output in the second-stage acceleration region.

  If it is determined in step S5 that the speed command output is equal to or less than the speed command output of the second-stage acceleration region, it is determined that the first-stage acceleration region is detected. In step S6, a speed increment 1 is added to the speed command input and the speed command output. It is judged whether it is large or small. If it is determined in step S6 that the speed command input is larger than the speed command output plus speed increment 1 (speed command input> speed command output + speed increment 1) (Yes in step S6), in step S7, The speed command output is switched to the speed command output obtained by adding the speed increment 1 to the speed command output (speed command output + speed increment 1) by the acceleration processing of the acceleration processing unit 16, and the speed increment (acceleration) is the magnitude of the speed increment 1. Limited to If it is determined in step S6 that the speed command input is smaller than the speed command output plus the speed increment 1 (No in step S6), in step S8, the acceleration command is not limited and the speed command input remains as it is. Command output.

  If it is determined in step S5 that the speed command output is greater than or equal to the speed command output in the second-stage acceleration region, it is determined that the second-stage acceleration region is present. The original size is added. If it is determined in step S9 that the speed command input is greater than the speed command output plus speed increment 2 (speed command input> speed command output + speed increment 2) (Yes in step S9), in step S10, The speed command output is switched to the speed command output by adding the speed increment 2 to the speed command output (speed command output + speed increment 2) by the acceleration processing of the acceleration processing unit 16, and the speed increment (acceleration) is the magnitude of the speed increment 2. Limited to If it is determined in step S9 that the speed command input is smaller than the speed command output plus the speed increment 2 (No in step S9), in step S11, the acceleration command is not limited and the speed command input remains as it is. Command output.

If it is determined in step S1 that the vehicle is in the accelerated state (NO in step S1), it is determined in step S12 whether the vehicle is in the decelerated state. The determination of the deceleration state is determined as the deceleration state when the difference between the previous speed command input and the current speed command input (previous speed command input−current speed command input) is negative. If it is determined that the deceleration state (Yes in step S12), the the switch a _5, a ₆ turns to ON in the controller 11, the large and small between the speed command input and the current speed in step S13 is compared, the speed command input Is smaller than the current speed (speed command input <current speed) (Yes in step S13), and in step S14, the current speed and the speed command output are compared in magnitude.

  If the current speed is smaller than the speed command output in step S14 (current speed <speed command output) (Yes in step S14), the speed command output initial value is set to the current speed in step S15, and the speed command output is set in step S16. Is determined to be less than or equal to the speed command output in the second-stage deceleration area (speed command output ≦ second-stage deceleration area). If the speed command input is greater than or equal to the current speed in step S13 (speed command input ≧ current speed) (No in step S13), and if the current speed is greater than the speed command output in step S14, or If they are equal (current speed ≧ speed command output) (No in step S14), it is determined in step S16 whether or not the speed command output is equal to or lower than the speed command output in the second-stage deceleration region.

  If it is determined in step S16 that the speed command output is equal to or greater than the speed command output in the second-stage deceleration area (speed command output ≧ second-stage deceleration area), it is determined that the second-stage deceleration area is detected. In step S17, the speed command output is determined. The original size is determined by subtracting the speed increment 4 from the input and speed command output. If it is determined in step S17 that the speed command input is smaller than the speed command output minus the speed increment 4 (speed command input <speed command output-speed increment 4) (Yes in step S17), in step S18, The speed command output is switched to the speed command output obtained by subtracting the speed increment 4 from the speed command output (speed command output-speed increment 4) by the deceleration process of the deceleration processing unit 18, and the speed increment (acceleration) is the magnitude of the speed increment 4. Limited to If it is determined in step S17 that the speed command input is larger than the value obtained by subtracting the speed increment 4 from the speed command output (No in step S17), the acceleration command is not limited in step S19 and the speed command input remains as it is. Output.

  In step S16, if the speed command output is equal to or lower than the speed command output in the second-stage deceleration area (speed command output ≦ second-stage deceleration area), it is determined that the first-stage deceleration area is used, and in step S20. Whether the speed command input and the speed command output are obtained by subtracting the speed increment 3 is determined. If it is determined in step S20 that the speed command input is smaller than the speed command output minus the speed increment 3 (speed command input <speed command output-speed increment 3) (Yes in step S20), in step S21, The speed command output is switched to the speed command output obtained by subtracting the speed increment 3 from the speed command output (speed command output-speed increment 3) by the deceleration processing of the deceleration processing unit 18, and the speed increment (acceleration) is the magnitude of the speed increment 3. Limited to If it is determined in step S20 that the speed command input is greater than the speed command output minus the speed increment 3 (No in step S20), the speed command input is directly output without being limited in step S22. It becomes.

In the determination whether or not the deceleration state of the step S12, (No in step S12) When it is determined that there is no acceleration or deceleration, the speed command input in step S23 the switch a ₉ turns ON in the controller 11 as it is Speed command output.

  In the acceleration limiting process in the speed command output as described above, for example, the acceleration in the acceleration state is changed from the speed increment 1 in the first-stage deceleration area to the speed increment 2 in the second-stage deceleration area (speed increment 1 <speed increment 2). When switching to (), if hysteresis is provided, the amount of change per unit time of the speed increment 2 (acceleration) at the time of switching is suppressed to be small, and the shock during acceleration / deceleration is further reduced.

  As described above, in the turning control device for a construction machine according to the present embodiment, the acceleration limitation is switched in multiple stages, so that the shock during acceleration / deceleration is reduced, the vibration of the cab is suppressed, and the ride comfort is reduced. As a result, the service life of the turning mechanism can be increased. Moreover, it is possible to prevent the turning operation from being excessively slow, and to suppress a reduction in work efficiency.

  By switching to reduce the absolute value of acceleration at the beginning of deceleration and increasing the acceleration in the middle, the flow of turning can be reduced, and at the moment of stopping, the acceleration is reduced to a small absolute value to reduce the shock of stopping. It is possible to eliminate the increase of shaking back.

  By providing hysteresis for switching the acceleration limit, the amount of change in acceleration per unit time at the time of switching can be kept small, and shocks during acceleration / deceleration can be further reduced.

  The present invention can be variously modified without departing from the spirit of the present invention, and the present invention naturally extends to the modified ones.

  It can be widely applied to construction machines equipped with an electric motor-driven turning mechanism that is essential to reduce the shock due to backlash at startup, increase the useful life of the turning mechanism, and to suppress the reduction in work efficiency. is there.

11 Controller (control means)
12 Operation lever 13 Input port 14 Output port 15A Acceleration processing system 15B Deceleration processing system 15C No acceleration / deceleration system 16 Acceleration processing unit 17 Speed increment input line 18 Deceleration processing unit 19 Speed increment input line

Claims (4)

In the excavator turning control device in which the speed of the turning of the turning body mounted with the cab is controlled by an electric motor,
The speed command of the electric motor of the turning, and having a control unit intends row by the speed command of the turning generated in response to the operation amount of the operating lever operated by an operator,
The control means includes
An acceleration processing system that selects a speed increment corresponding to the speed command from a plurality of speed increments in an acceleration state and switches to multiple stages, and a speed increment corresponding to the speed command from a plurality of speed increments in a deceleration state Built-in deceleration processing system to switch,
A shovel turning control device that outputs a speed command output by adding or subtracting the selected speed increment to or from the speed increment .   2. The excavator turning control device according to claim 1, wherein the acceleration limitation in the speed command is switched by a speed command output from the control means.   2. The excavator turning control device according to claim 1, wherein the acceleration limit in the speed command is switched according to the actual turning speed of the turning body.   4. The excavator turning control device according to claim 1, wherein hysteresis is provided for switching acceleration limitation in the speed command.

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