JP4769670B2 - Actuator drive device for construction machinery - Google Patents

Description

  The present invention relates to an actuator driving device for a construction machine such as a hydraulic excavator having a plurality of electric motors and a battery.

  In the field of construction machinery, hydraulic actuators are generally widely used because equipment can be made smaller and lighter with respect to output. However, the hydraulic actuator is less energy efficient than the electric actuator. Therefore, even in construction machines, there is a concept of mounting an electric actuator instead of a hydraulic actuator.

  However, in order to distribute the output of the hydraulic pump, which is the hydraulic source, in the system that drives multiple hydraulic actuators, a system that properly distributes the output of the hydraulic pump has been constructed. In this case, there is no system for properly distributing the power capacity, and when the power capacity is insufficient, power is preferentially supplied to the actuator with a light load.

For this reason, conventionally, there has been proposed an actuator driving device for a construction machine provided with control means for controlling the total power of the electric actuators generated simultaneously to be equal to or less than the power capacity without increasing the power capacity. (See Patent Document 1).
JP 2003-155760 A

  In the prior art disclosed in Patent Document 1 described above, since individual control of each electric actuator corresponding to the battery is not performed, normal excavation work or the like is possible even when the remaining battery power is reduced. End up. For this reason, the operator is unaware that the amount of remaining battery power is very small, and there is a concern that the battery will run out before the hydraulic excavator goes to the charging base, for example.

  The present invention has been made from the above-described prior art, and an object of the present invention is to provide an actuator driving device for a construction machine that allows an operator to notice that the remaining amount of battery power has become very small. is there.

To achieve this object, the present invention comprises a plurality of electric motors and a battery, and each of the electric motors is operated as an actuator or a drive source for driving the actuator by the electric power from the battery. In the actuator drive device of a machine, when the remaining power amount of the battery is reduced to a small amount of a predetermined amount or less, the maximum possible output for the electric motor is obtained when the remaining power amount of the battery exceeds the predetermined amount. Set to a predetermined maximum possible output smaller than the maximum possible output, and determine whether the total target output of the motor is larger than the predetermined maximum possible output in the state set to the predetermined maximum possible output in this way When the total target output of the electric motor is determined to be less than the predetermined maximum possible output in this determination Maintaining the electric motor each target output, when said total target output of the electric motor is determined that the predetermined maximum possible output is greater than the above determination, reducing the output command to either of the electric motor of said electric motor Thus, it is characterized in that there is provided electric power control means for performing control for suppressing the total target output of the electric motor to the predetermined maximum possible output .

The present invention configured as described above provides the maximum possible output to the electric motor when the remaining power amount of the battery is reduced to a minute amount below a predetermined amount, and the maximum possible output when the remaining power amount of the battery exceeds the predetermined amount. This is set to a predetermined maximum possible output smaller than the output, and in this state set to the predetermined maximum possible output, it is determined whether or not the total target output of the motor is larger than the predetermined maximum possible output. When it is determined that the total target output of the motor is greater than the predetermined maximum possible output, the power control means performs control to reduce the output command to any one of the plurality of motors and suppress the total power consumption. As a result, the movement of the actuator driven by the electric motor whose output command has decreased is reduced. As the actuator moves in this manner, the operator can be made aware that the amount of remaining power in the battery has become very small.

  Further, the present invention is the above invention, wherein the power control means preferentially drives the specific motor and outputs to another motor when the remaining power amount of the battery is reduced to a minute amount equal to or less than a predetermined amount. It is characterized by performing control to reduce the command.

  Moreover, the present invention is characterized in that, in the above-mentioned invention, the specific motor is a traveling motor. The present invention configured as described above allows the construction machine to immediately travel to the charging base when the operator notices that the remaining power amount of the battery has become very small.

  Further, in the above invention, a warning means for giving a warning to the operator when the remaining power amount of the battery is reduced to a minute amount equal to or less than a predetermined amount is provided, and a target output for any one of the motors can be adjusted. It is characterized by having manual power adjustment means. According to the present invention configured as described above, it is possible to make the operator more surely recognize that the remaining power amount of the battery has become very small via the warning means, and to operate the manual power adjusting means. The timing at which the amount of electric power is determined to be small can be changed as desired by the operator.

  Further, the present invention is characterized in that, in the above invention, the construction machine comprises a hydraulic excavator.

The present invention sets the maximum possible output for the electric motor to a predetermined value smaller than the maximum possible output when the remaining power amount of the battery exceeds the predetermined amount when the remaining power amount of the battery is reduced to a small amount of the predetermined amount or less. In this state, it is determined whether the total target output of the motor is larger than the predetermined maximum possible output, and this determination determines the total target of the motor. When it is determined that the output is greater than the predetermined maximum possible output , the battery remaining power is provided by performing power control means for performing control to reduce the output command to any one of the motors to reduce the total power consumption. When the amount becomes a very small amount below the specified amount, the movement of the actuator driven by the motor whose output command has been reduced decreases, and the remaining power of the battery is shown to the operator. It is possible to notice that it's a very small amount. Thereby, it is possible to prevent the battery from running up, which has been a concern in the past.

  Hereinafter, the best mode for carrying out an actuator driving device for a construction machine according to the present invention will be described with reference to the drawings.

  FIG. 1 is a side view showing a hydraulic excavator cited as an example of a construction machine provided with an embodiment of an actuator driving apparatus according to the present invention, and FIG. 2 is a block diagram showing a main configuration of the embodiment.

  As shown in FIG. 1, a hydraulic excavator exemplified as an example of a construction machine provided with the actuator driving device according to the present invention includes a traveling body 10, a revolving body 20 provided on the traveling body 10, and the revolving body. 20 is provided with a front working machine 30 that is attached to 20 so as to be rotatable in the vertical direction.

  The traveling body 10 described above includes a pair of crawlers 11 and a crawler frame 12, and a right traveling motor 13 and a left traveling motor 14 that drive each of the pair of crawlers 11, as shown in FIG.

  The revolving body 20 described above is provided on the revolving frame 21, the revolving frame 21, a hydraulic pump motor 22 that forms a drive source for the hydraulic actuator, a battery 24, a revolving motor 25, and the revolving motor 25. A turning mechanism 26 that includes a speed reducing mechanism that decelerates the rotation of the turning body 20 and that drives the turning body 20 to turn with respect to the traveling body 10 by the driving force of the turning electric motor 25 is provided. Furthermore, a hydraulic control mechanism 40 including a hydraulic pump 41 and a hydraulic control valve 42 shown in FIG. 2 for driving and controlling the hydraulic actuator is provided on the swing frame 21 of the swing body 20.

  The front working machine 30 described above includes a boom 31 attached to the swing body 20 so as to be able to be raised and lowered, a boom cylinder 32 that drives the boom 31, and an arm 33 that is pivotally supported near the tip of the boom 31. The arm cylinder 34 that drives the arm 33, the bucket 35 that is pivotally supported at the tip of the arm 33, and the bucket cylinder 36 that drives the bucket 35 are provided.

  In addition to the above-described configuration, as shown in FIG. 2, the present embodiment includes an operation device 54 that operates a hydraulic actuator such as a boom cylinder 32, an arm cylinder 34, and a bucket cylinder 36, and a corresponding one of the operation devices 54. The turning inverter 28a that drives the turning electric motor 25 in accordance with the operation of the operating device to be driven, and the right traveling motor 13 and the left traveling motor 14 are driven in accordance with the operation of the corresponding operating device of the operating device 54, respectively. A right travel inverter 28b, a left travel inverter 28c, and a hydraulic pump inverter 52 that drives the hydraulic pump motor 22 in accordance with the operation of the corresponding operation device among the operation devices 54. A rotation speed sensor 22 a is attached to the hydraulic pump electric motor 22.

  In addition, a control signal for controlling driving of the hydraulic pump motor 22, the turning motor 25, the right traveling motor 13, and the left traveling motor 14 is output in accordance with the operation of the corresponding one of the operation devices 54. The controller 55 is provided. The controller 55 reduces the output command to any one of the above-described motors when the remaining power amount of the battery 24 is reduced to a minute amount less than a predetermined amount, for example, 30% or less. Power control means for performing control to reduce power consumption is configured. The controller 55 preferentially drives the specific motor, for example, the right traveling motor 13 and the left traveling motor 14 when the remaining power amount of the battery 24 is reduced to 30% or less, and outputs commands to other motors. Control is performed to reduce the.

  For the right traveling motor 13 and the left traveling motor 14 described above, torque control type control is performed in which a torque command corresponding to the operation of the corresponding operation device among the operation devices 54 is given to the motor. For the pump motor 22, speed command type control is performed in which a speed command corresponding to the operation of the corresponding operation device of the operation devices 54 is given to the motor. The right traveling motor 13 and the left traveling motor 14 have actual rotational speed measuring means such as a resolver, for example, and the hydraulic pump motor 22 calculates an actual torque based on an input current value.

  Further, the present embodiment includes a battery amount detection unit that detects the remaining power amount of the battery 24. This battery amount detection means is well-known, for example, detects the remaining power amount of the battery 24 by calculating the release terminal voltage, or how much current has flowed since the battery 24 is fully charged, that is, integrates the current. Thus, the battery 24 is configured to detect the remaining power amount.

  Further, as shown in FIG. 3, the controller 55 described above includes a right traveling motor command torque Tcom1 output in accordance with operation of the corresponding operation device of the operation device 54 and the right traveling motor actual rotational speed Nrel1. Multiplier 71 for obtaining the product of the left traveling motor and the multiplier for obtaining the product of the left traveling motor command torque Tcom2 output in association with the operation of the corresponding operation device of the operation device 54 and the left traveling motor actual rotational speed Nrel2. 72, a multiplier 73 for obtaining the product of the hydraulic pump motor command rotational speed Ncom3 output in accordance with the operation of the corresponding operating device of the operating device 54 and the hydraulic pump motor actual torque Trel3. Further, the value obtained by the multiplier 71 is multiplied by the proportionality constant C to calculate the right running motor target output Er1, and the value obtained by the multiplier 72 is multiplied by the proportionality constant C and left running. A proportional unit 75 for calculating the motor target output Er2 for the hydraulic pump, and a proportional unit 76 for calculating the target output Er3 for the hydraulic pump by multiplying the value obtained by the multiplier 73 by the proportional constant C, and the proportional units 74, 75, 76 Is added to add the target outputs Er1, Er2, Er3 from each of them, and calculate the total target output Esum.

  Further, as shown in FIG. 5, the controller 55 multiplies the right traveling motor target output Er1 by a proportional constant 1 / C and multiplies the left traveling motor target output Er2 by a proportional constant 1 / C. The proportional device 82, the proportional device 83 that multiplies the hydraulic pump motor target output Er3 by a proportional constant 1 / C, and the output value of the proportional device 81 is multiplied by the inverse 1 / Nrel1 of the right running motor actual rotational speed. A multiplier 84 that outputs a control signal corresponding to the right traveling motor command torque Tcom1A to the right traveling inverter 28b, and an output value of the proportional device 82 is multiplied by an inverse 1 / Nrel2 of the actual rotational speed of the left traveling motor; A multiplier 85 that outputs a control signal corresponding to the obtained left travel motor command torque Tcom2A to the left travel inverter 28c, and an output value of the proportional unit 83 is an inverse of the actual torque of the hydraulic pump motor. / Trel3 multiplied by, and a multiplier 86 for outputting a control signal corresponding to the determined hydraulic pump motor command rotational speed Ncom3A hydraulic pump inverter 52.

  Further, as shown in FIG. 2, the present embodiment is a warning means for giving a warning to the operator when the remaining power amount of the battery 24 is reduced to a minute amount of a predetermined amount or less, for example, 30% or less, for example, a controller. Warning lamp 57 that is turned on in response to a signal output from 55, and manual power adjustment means that can manually adjust a target output for an electric motor whose output command is controlled to decrease, for example, the hydraulic pump electric motor 22, that is, an output adjustment dial 56 It also has.

  The processing operation mainly performed in the controller 55 of the present embodiment configured as described above will be described below based on the flowchart shown in FIG.

  When the control is started (procedure S1), it is determined whether or not the remaining power amount of the battery 24 obtained by the battery amount detecting means described above is very small, that is, 30% or less (procedure S2). If it is determined in this determination that the remaining power amount of the battery 24 is not 30% or less, whether or not the total target output Esum obtained as shown in FIG. 3 is greater than the maximum possible output Emax set in advance. It is determined (procedure S3). When it is determined to be large in this determination, each of the right traveling motor target output Er1, the left traveling motor target output Er2, and the hydraulic pump motor target output Er3 obtained as shown in FIG. By multiplying Emax / Esum (procedure S4), Er1 + Er2 + Er3 = Emax is set, and the control is terminated (procedure S10). When the total target output Esum is determined to be equal to or less than the maximum possible output Emax in step S3 described above, the right traveling motor target output Er1, the left traveling motor target output Er2, and the hydraulic pump motor target output Er3 are left as they are ( Procedure S5), the control is terminated (procedure S10).

  On the other hand, when it is determined in step S2 described above that the remaining power amount of the battery 24 is a very small amount of 30% or less, the output adjustment that suppresses the maximum possible output Emax so that the amount of the battery 24 is long. Processing to replace the maximum possible output EmaxA set by the dial 56 or the like is performed (step S6). Here, the maximum possible output EmaxA is, for example, about 30% to 50% of Emax. Subsequently, it is determined whether or not the total target output Esum is larger than the maximum possible output Emax (step S7). When it is determined in this determination that the total target output Esum is greater than the maximum possible output Emax, the right traveling motor target output Er1 and the left traveling motor target output Er2 are maintained as they are, and the total target output Esum is the maximum possible output Emax. For the portion exceeding, the hydraulic pump electric motor target output Er3 is decreased (procedure S8), and the control is terminated (procedure S10). When it is determined in step S7 that the total target output Esum is equal to or less than the maximum possible output Emax, the right traveling motor target output Er1, the left traveling motor target output Er2, and the hydraulic pump motor target output Er3 are left as they are. It is held (procedure S9) and the control is terminated (procedure S10).

  As shown in FIG. 5, the right traveling motor target output Er1, the left traveling motor target output Er2, and the hydraulic pump motor target output Er3 obtained in the steps S4, S5, S8, and S9 described above are proportional to each other. 81, 82, 83 and multiplied by a proportional constant 1 / C, and further input to multipliers 84, 85, 86 and multiplied by 1 / Nrel1, 1 / Nrel2, 1 / Trel3, respectively. The command torque Tcom1A, the left travel motor command torque Tcom2A, and the hydraulic pump motor command rotation speed Ncom3A are obtained. The control signals corresponding to the right traveling motor command torque Tcom1A, the left traveling motor command torque Tcom2A, and the hydraulic pump motor command rotation speed Ncom3A are the right traveling inverter 28b, the left traveling inverter 28c, and the hydraulic pressure as described above. It is output to the pump inverter 52. As a result, when the remaining power amount of the battery 24 becomes a very small amount of 30%, the rotational speed of the hydraulic pump motor 22 driven via the hydraulic pump inverter 52 decreases, and the discharge amount from the hydraulic pump 41 is reduced. As a result, the amount of pressure oil supplied to the boom cylinder 32, the arm cylinder 34, and the bucket cylinder 36 decreases.

  When the remaining power of the battery 24 becomes a small amount of 30% or less, a signal is output from the controller 55 to the warning lamp 57, and the warning lamp 57 is turned on.

  As described above, the setting of EmaxA in step S6 of FIG. 4 may be about 30% to 50% of Emax. However, if the operator wants to change this value, the output adjustment dial 56 is turned manually. You can adjust with.

  According to this embodiment configured as described above, a control signal is output from the controller 55 to, for example, the right traveling inverter 28b and the left traveling inverter 28c in accordance with the operation of the corresponding operation device of the operation device 54, and the right traveling is performed. The electric motor 13 and the left traveling electric motor 14 are driven, and the crawler 11 shown in FIG. 1 is moved to travel. For example, a control signal is output from the controller 55 to the hydraulic pump inverter 52 in accordance with the operation of the corresponding operation device of the operation device 54, and the hydraulic pump motor 22 is driven. As a result, the hydraulic pump 41 is driven, and the pressure oil discharged from the hydraulic pump 41 is supplied to the corresponding hydraulic actuators such as the boom cylinder 32, the arm cylinder 34, and the bucket cylinder 36 via the hydraulic control valve 42, so that the front work The machine 30 is driven to perform desired work such as excavation work.

  In such a state, when the remaining power amount of the battery 24 is reduced to a very small amount of 30% or less, the discharge amount of the hydraulic pump 41 driven by the hydraulic pump motor 22 whose output command is reduced as described above decreases. Then, the operating speeds of the boom cylinder 32, the arm cylinder 34, and the bucket cylinder 26 are reduced, and the movement of the front work machine 30 is slower than before. As a result, the operator can be made aware that the remaining power amount of the battery 24 has become a very small amount of 30% or less, and can be urged to take measures to prevent the battery from running out.

  Further, when the remaining power amount of the battery 24 becomes a very small amount of 30% or less, the right traveling motor 13 and the left traveling motor 14 are preferentially driven. Can be run quickly.

  Further, as described above, the warning lamp 57 is turned on when the remaining power of the battery 24 becomes a very small amount of 30% or less, so that the operator can be more surely recognized that such a state is present. it can. Further, by adjusting the output adjustment dial 56, it is possible to change the timing at which it is determined that the remaining power amount of the battery 24 has become very small as desired by the operator.

  In the above-described embodiment, when the remaining power amount of the battery 24 becomes a very small amount of 30% or less, the right traveling motor 13 and the left traveling motor 14 are given priority by the control signal output from the controller 55. However, the present invention is not limited to such a control. For example, when the remaining power amount of the battery 24 becomes very small in this way, the preferential driving of the right traveling motor 13 and the left traveling motor 14 is maintained, but the output to the turning motor 25 is reduced. You may make it perform control to perform. Even in such a configuration, the operator can be made aware that the amount of remaining power of the battery 24 has become very small, and the same effect as the above embodiment can be obtained.

It is a side view which shows the hydraulic excavator mentioned as an example of the construction machine with which one Embodiment of the actuator drive device which concerns on this invention is provided. It is a block diagram which shows the principal part structure of this embodiment. It is a figure which shows the principal part structure of the controller with which this embodiment is equipped. It is a flowchart which shows the process sequence in the controller with which this embodiment is equipped. It is a figure which shows the principal part structure of the controller with which this embodiment is equipped.

Explanation of symbols

10 traveling body 13 right-hand drive motor (specific motor)
14 Left-hand drive motor (specific motor)
DESCRIPTION OF SYMBOLS 20 Revolving body 22 Hydraulic pump electric motor 22a Rotational speed sensor 24 Battery 25 Turning electric motor 28a Turning inverter 28b Right running inverter 28c Left running inverter 30 Front work machine 32 Boom cylinder 34 Arm cylinder 36 Bucket cylinder 40 Hydraulic control mechanism 41 Hydraulic pump 42 Hydraulic control valve 52 Hydraulic pump inverter 55 Controller (power control means)
56 Output adjustment dial (Manual power adjustment means)
57 Warning lamp (Warning means)
DESCRIPTION OF SYMBOLS 71 multiplier 72 multiplier 73 multiplier 74 proportional device 75 proportional device 76 proportional device 77 adder 81 proportional device 82 proportional device 83 proportional device 84 multiplier 85 multiplier 86 multiplier

Claims (5)

In an actuator drive device for a construction machine, comprising a plurality of electric motors and a battery, wherein each of the electric motors is operated as an actuator by electric power from the battery or as a drive source for driving the actuator.
When the remaining amount of power of the battery is reduced to a very small amount equal to or less than a predetermined amount, the maximum possible output for the electric motor is set to a predetermined value smaller than the maximum possible output when the remaining power amount of the battery exceeds the predetermined amount. In the state where the predetermined maximum possible output is set as described above, it is determined whether or not the total target output of the motor is larger than the predetermined maximum possible output. When the total target output of the motor is determined to be less than or equal to the predetermined maximum possible output, the target output of each of the motors is maintained, and it is determined in the determination that the total target output of the motor is greater than the predetermined maximum possible output. when it is in, to reduce the output command to either of the electric motor of said electric motor, the total target output of the electric motor to the predetermined maximum possible output Actuator drive device for a construction machine characterized by comprising a power control means for performing obtaining control. In the invention of claim 1,
The power control means performs control to preferentially drive a specific motor and reduce an output command to another motor when the remaining power amount of the battery is reduced to a minute amount equal to or less than a predetermined amount. Actuator drive device for construction machinery. In the invention of claim 2,
An actuator driving apparatus for a construction machine, wherein the specific motor is a traveling motor. In the invention of claim 1,
Provided with a warning means for giving a warning to an operator when the remaining power amount of the battery is reduced to a small amount of a predetermined amount or less, and a manual power adjustment means capable of adjusting a target output for any one of the motors An actuator driving device for a construction machine. In the invention according to any one of claims 1 to 4,
A construction machine actuator driving device, wherein the construction machine comprises a hydraulic excavator.

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