JP2016172999A - Construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a construction machine that reflects more effectively an intention of an operator in output power distribution.SOLUTION: A shovel according to an embodiment of the present invention performs output limitation at least on either when a total of hydraulic output and revolving output exceeds driving source output. Also, the shovel sets the hydraulic output or the revolving output as priority output based on detected information or input information when performing the output limitation, and determines output distribution respectively for the hydraulic output and the revolving output based ont the setting. The output distribution of the output that has been set as the priority output is higher than the output distribution of the other, or higher than prescribed reference output distribution.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a construction machine including a turning electric motor.

  Control of hybrid construction machinery that distributes engine power as a drive source to the hydraulic pump and generator, drives the electric motor for turning with the power generated by the generator, and drives the hydraulic actuator with hydraulic oil supplied by the hydraulic pump An apparatus is known (see Patent Document 1).

  In this hybrid construction machine, the turning electric motor is used for turning the upper turning body, and the hydraulic actuator is used for driving a boom provided in the upper turning body. When the hydraulic actuator and the turning electric motor are operated simultaneously, the control device limits the output power of the turning electric motor and preferentially distributes the output power to the hydraulic actuator.

JP 2011-174512 A

  However, the above-described control device cannot cope with a case where the operator wants to preferentially distribute output power to the turning electric motor.

  The construction machine according to the embodiment of the present invention is a construction machine that executes at least one output restriction when the sum of the hydraulic output and the turning output exceeds the drive source output, and the detection information when executing the output restriction. Alternatively, the hydraulic output or the turning output is set as a priority output based on the input information, the output distribution of the hydraulic output and the turning output is determined based on the setting, and the output distribution set as the priority output has priority. It is higher than the output distribution when not set as output, or higher than a predetermined reference output distribution.

  By the above-described means, a construction machine that can more appropriately reflect the operator's intention in the distribution of output power can be provided.

It is a side view of an excavator. It is a block diagram which shows the structural example of the drive system of the shovel of FIG. It is a figure which shows the relationship between the input parameter in a drive source output allocation process, and an output parameter. It is a flowchart which shows the flow of a priority output setting process. It is a flowchart which shows the flow of an output distribution determination process. It is a graph explaining an example of the derivation method of a temporary balance point. It is a graph which shows an example of transition of the ideal balance point at the time of oil pressure priority, and a temporary balance point. It is a graph which shows an example of transition of the ideal balance point at the time of turning priority, and a temporary balance point. It is a flowchart which shows the flow of another example of an output distribution determination process. It is a graph explaining an example of the control method of the variation | change_quantity of a priority output when a non-priority output changes.

  FIG. 1 is a side view showing an excavator as an example of a construction machine to which the present invention is applied.

  An upper swing body 3 is mounted on the lower traveling body 1 of the excavator via a swing mechanism 2. 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, the arm 5, and the bucket 6 constitute an excavation attachment, and are hydraulically driven by the boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9, respectively. The upper swing body 3 is provided with a cabin 10 and is mounted with a power source such as an engine.

  FIG. 2 is a block diagram showing the configuration of the excavator drive system according to the embodiment of the present invention. In FIG. 2, the mechanical power system is indicated by a double line, the high-pressure hydraulic line is indicated by a thick solid line, the pilot line is indicated by a broken line, and the electric drive / control system is indicated by a thin solid line.

  The engine 11, the motor generator 12, and the main pump 14 are connected via a transmission 13. In the present embodiment, the first input shaft of the transmission 13 is connected to the rotation shaft of the engine 11, and the second input shaft of the transmission 13 is connected to the rotation shaft of the motor generator 12. Therefore, the motor generator 12 that functions as an electric motor can assist the rotation of the engine 11. Further, the motor generator 12 functioning as a generator can generate power using the output of the engine 11. Further, the rotary shaft of the main pump 14 is connected to the output shaft of the transmission 13. Therefore, the main pump 14 can be driven by at least one of the engine 11 and the motor generator 12. A control valve 17 is connected to the main pump 14 via a high pressure hydraulic line 16. A pilot pump 15 may be connected to the output shaft of the transmission 13 in the same manner as the main pump 14. However, the above-described connection relationship is merely an example, and the two pumps do not necessarily have to be connected to the output shaft of the transmission 13. For example, the main pump 14 may be driven by an electric motor.

  The control valve 17 is a control device that controls a hydraulic system in the excavator. The hydraulic motors 1A (for right) and 1B (for left), the boom cylinder 7, the arm cylinder 8, the bucket cylinder 9 and the like for the lower traveling body 1 are connected to the control valve 17 via a high pressure hydraulic line. The hydraulic system includes hydraulic motors 1A (for right) and 1B (for left) for the lower traveling body 1, a boom cylinder 7, an arm cylinder 8, a bucket cylinder 9, a main pump 14, and a control valve 17.

  A storage system 120 including a capacitor 19 as a storage battery is connected to the motor generator 12 via an inverter 18. In addition, a turning electric motor 21 is connected to the power storage system 120 via an inverter 20. A resolver 22, a mechanical brake 23, and a turning transmission 24 are connected to the rotating shaft 21 </ b> A of the turning electric motor 21. An operation device 26 is connected to the pilot pump 15 through a pilot line 25. The turning electric motor 21, the inverter 20, the resolver 22, the mechanical brake 23, and the turning transmission 24 constitute an electric turning system as a load drive system.

  The operating device 26 includes a lever 26A, a lever 26B, and a pedal 26C. The lever 26A, lever 26B, and pedal 26C are connected to the control valve 17 and the pressure sensor 29 via a hydraulic line 27 and a hydraulic line 28. The pressure sensor 29 is connected to a controller 30 that performs drive control of the electric system.

  The controller 30 is a control device as a main control unit that performs drive control of the shovel. In the present embodiment, the controller 30 is constituted by an arithmetic processing unit including a CPU and an internal memory, and various functions are realized by the CPU executing a drive control program stored in the internal memory.

  Further, the controller 30 converts the signal supplied from the pressure sensor 29 into a speed command, and performs drive control of the turning electric motor 21. In this case, the signal supplied from the pressure sensor 29 corresponds to a signal representing an operation amount when the operation device 26 is operated to turn the turning mechanism 2.

  Next, referring to FIG. 3, when the turning combined operation is performed, the controller 30 distributes the engine output as the drive source output to the hydraulic output and the turning output (hereinafter referred to as “drive source output distribution process”). ). FIG. 3 is a diagram showing the relationship between the input and output to the controller 30 in the drive source output distribution process. The turning combined operation is, for example, a combined operation of the turning electric motor 21 operation (turning operation) and the hydraulic actuator operation (hydraulic operation). It may be a combined operation of a turning operation and two or more hydraulic actuator operations. Below, the case where the turning combined operation of turning operation and operation of the boom cylinder 7 as a hydraulic actuator is performed is demonstrated as an example. The hydraulic output is, for example, a pump horsepower command for controlling the output (absorption horsepower) of the main pump 14. The turning output is, for example, a turning command for controlling a motor generator output (generated power) necessary for turning.

  Schematically, the controller 30 outputs a command relating to each of the hydraulic output and the turning output based on, for example, input information or detection information relating to each of the hydraulic output and the turning output. Further, when the sum of the hydraulic output and the turning output exceeds the drive source output, at least one output restriction is executed. When executing the output restriction, the hydraulic output or the turning output is set as the priority output based on the detection information or the input information, and the output distribution of each of the hydraulic output and the turning output is determined based on the setting. The output distribution set as the priority output is set to be higher than the output distribution when not set as the priority output, or higher than the predetermined reference output distribution. Hereinafter, specific examples of the configuration and functions of the controller 30 will be described.

  The controller 30 includes a hydraulic pressure output estimation unit 31, a turning output estimation unit 32, a priority output setting unit 33, a pump horsepower command generation unit 34, a rotation command generation unit 35, and an output distribution determination unit 36.

  The hydraulic output estimator 31 is a functional element that estimates the required hydraulic output from the hydraulic lever input. The estimated required oil pressure output is limited as necessary. The hydraulic lever input is related to the operation amount of the hydraulic actuator. For example, an operation input to the boom lever, and a pressure signal generated by the pressure sensor 29 is employed. The hydraulic output estimator 31 may estimate the required hydraulic output in consideration of the discharge pressure of the main pump 14 and the load pressure of the hydraulic actuator.

  The turning output estimation unit 32 is a functional element that estimates a requested turning output from a turning lever input. Note that the estimated required turning output is limited as necessary. The turning lever input is related to the amount of turning operation. For example, a pressure signal generated by the pressure sensor 29, which is an operation input to the turning lever, is employed. The turning output estimation unit 32 may estimate the required turning output by additionally considering the discharge pressure of the main pump 14, the load pressure of the hydraulic actuator, and the like.

  The priority output setting unit 33 is a functional element that determines a priority axis (priority output) intended by the operator. The priority output setting unit 33 sets the hydraulic output or the turning output as the priority output based on, for example, detection information such as pressure detected by the pressure sensor 29 or input information such as a calculation result of the controller 30. In this embodiment, the turning output is set as a priority output when the turning lever is first operated during the combined turning operation, and the hydraulic output is prioritized when the boom lever is operated first during the combined turning operation. Set as output.

  The priority output setting unit 33 has a function of resetting the priority output as necessary. For example, when the turning output is set as the priority output, the setting of the priority output is reset when the turning lever is returned to the neutral position. Alternatively, if the hydraulic output is set as a priority output, the priority output setting is reset when the boom lever is returned to the neutral position.

  Here, with reference to FIG. 4, processing in which the priority output setting unit 33 sets priority output (hereinafter referred to as “priority output setting processing”) will be described. FIG. 4 is a flowchart showing the flow of the priority output setting process.

  First, the priority output setting unit 33 determines which of the turning lever and the boom lever has been operated first (step S1).

  When it is determined that the turning lever has been operated first (the turning lever in Step S1), the priority output setting unit 33 sets the turning output as the priority output (Step S2).

  If it is determined that the boom lever has been operated first (the boom lever in step S1), the priority output setting unit 33 sets the hydraulic output as the priority output (step S3).

  In addition, the priority output setting part 33 does not need to set a priority output, when it determines with the turning lever and the boom lever having been operated simultaneously.

  Thereafter, the priority output setting unit 33 determines whether the previously operated lever has been returned to the neutral position (step S4). The current priority output setting is maintained until the previously operated lever is returned to the neutral position. For example, when the turning lever has been operated first, the turning output is set as the priority output until the turning lever is returned to the neutral position. Alternatively, when the boom lever has been operated first, the hydraulic output is set as the priority output until the boom lever is returned to the neutral position.

  When it is determined that the previously operated lever has been returned to the neutral position (YES in step S4), the priority output setting unit 33 resets the priority output setting (step S5).

  In this way, the priority output setting unit 33 sets one of the hydraulic pressure output and the turning output as the priority output in the combined turning operation. Therefore, the operator's intention to prioritize the priority output can be reflected in the shovel control. In the following, the one that is not set as the priority output among the hydraulic output and the turning output is referred to as “non-priority output”.

  Returning to FIG. 3, the description will be continued. The pump horsepower command generation unit 34 is a functional element that generates a pump horsepower command based on the required hydraulic pressure output from the hydraulic output estimation unit 31. For example, the pump horsepower command generation unit 34 refers to a reference table stored in advance in a storage medium or the like, and derives a pump horsepower command corresponding to the current required hydraulic pressure output. Then, the pump horsepower command is output to a regulator (not shown) of the main pump 14. Further, the pump horsepower command generation unit 34 receives the pump horsepower command upper limit value from the output distribution determination unit 36. If the derived pump horsepower command is greater than or equal to the pump horsepower command upper limit value, the pump horsepower command upper limit value is output as the final pump horsepower command. If the derived pump horsepower command is less than the pump horsepower command upper limit, the pump horsepower command is output as it is as the final pump horsepower command.

  The turning command generation unit 35 is a functional element that generates a turning command based on the requested turning output output by the turning output estimation unit 32. For example, the turning command generation unit 35 refers to a reference table stored in advance in a storage medium or the like, and derives a turning command corresponding to the current requested turning output. Then, the turning command is output to the motor generator 12. Further, the turning command generation unit 35 receives the turning command upper limit value from the output distribution determination unit 36. If the derived turn command is equal to or greater than the turn command upper limit value, the turn command upper limit value is output as the final turn command. If the derived turning command is less than the turning command upper limit value, the turning command is output as it is as a final turning command.

  When the sum of the hydraulic pressure output and the turning output exceeds the driving source output, the output distribution determining unit 36 executes the hydraulic pressure limitation to execute at least one of the hydraulic output and the turning output so that the total becomes equal to or less than the driving source output. It is a functional element that determines the output distribution of the output and the turning output. The hydraulic output, the turning output, and the drive source output are expressed in terms of power [kW], for example.

  Specifically, the output distribution determination unit 36 determines the pump horsepower command upper limit value and the swing command upper limit value based on the outputs of the hydraulic pressure output estimation unit 31, the turning output estimation unit 32, and the priority output setting unit 33, for example. decide. Then, the pump horsepower command upper limit value is output to the pump horsepower command generating unit 34, and the turning command upper limit value is output to the turning command generating unit 35.

  Here, with reference to FIG. 5, an example of a process in which the output distribution determination unit 36 determines each output distribution of the hydraulic output and the turning output (hereinafter, referred to as “output distribution determination process”) will be described. FIG. 5 is a flowchart illustrating an exemplary flow of output distribution determination processing.

  Schematically, the output distribution determination unit 36, when the total calculated force, which is the sum of the required hydraulic output and the required turning output, exceeds a predetermined reference value, the required hydraulic output and Limit at least one of the required turning outputs. Further, when the total calculated force is equal to or less than a predetermined reference value, the required hydraulic pressure output and the required turning output at that time are employed as they are. Details of an example of the output distribution determination process will be described below.

  First, the output distribution determination unit 36 determines whether the combined calculation force exceeds the reference value (step S11). The combined calculation force is, for example, the sum of the requested hydraulic output output from the hydraulic output estimating unit 31 and the requested turning output output from the turning output estimating unit 32. Processing when it is determined that the combined calculation force is equal to or less than the reference value (NO in step S11) will be described later.

  When it is determined that the combined calculation force exceeds the reference value (YES in step S11), the output distribution determination unit 36 derives a temporary balance point corresponding to the ideal balance point (step S12). The ideal balance point is a two-dimensional value having the required hydraulic pressure output and the required turning output as components. Similar to the ideal balance point, the provisional balance point is a two-dimensional value having the required hydraulic pressure output and the required turning output as components, and the total calculated force is equal to the reference value.

  FIG. 6 is a graph for explaining an example of a method for deriving a provisional balance point, where the hydraulic output is arranged on the vertical axis and the turning output is arranged on the horizontal axis. Further, each of the hydraulic output and the turning output is represented by a ratio [%] to the maximum output. Specifically, if the current hydraulic output is 50 [kW] and the maximum hydraulic output is 100 [kW], the current hydraulic output is represented as 50 [%]. For convenience of explanation, both the maximum hydraulic pressure output and the maximum turning output are set to 100 [kW]. The same applies to the following graphs.

  FIG. 6 shows a state where the boom lever is operated as a full lever and the swing lever is operated as a half lever as an example. In this case, the required hydraulic output output from the hydraulic output estimation unit 31 is 100 [%], and the required turning output output from the turning output estimation unit 32 is 20 [%]. Point P0 corresponds to the ideal balance point at this time.

  A line segment BL is a reference value boundary line representing the maximum drive source output as a reference value. Therefore, if the point P0 is outside the area indicated by hatching, it means that the combined calculation force exceeds the reference value. The point Q0 is an example of the provisional balance point at this time, and is located at the intersection of the line segment connecting the ideal balance point P0 and the origin and the reference value boundary line BL. Therefore, the ratio between the temporary hydraulic output H0 [%] indicated by the temporary balance point Q0 and the temporary turning output S0 [%] is the ratio between the required hydraulic output 100 [%] indicated by the ideal balance point P0 and the required turning output 20 [%]. be equivalent to. However, the provisional balance point may be derived using other methods. For example, it may be derived as a point on the reference value boundary line BL other than the intersection of the line segment connecting the ideal balance point P0 and the origin and the reference value boundary line BL. For example, an intersection of a line segment parallel to the horizontal axis passing through the ideal balance point P0 and the reference value boundary line BL, an intersection of a line segment parallel to the vertical axis passing through the ideal balance point P0 and the reference value boundary line BL, or It may be derived as an intersection of a line segment having a predetermined inclination passing through the ideal balance point P0 and the reference value boundary line BL.

  Returning to FIG. After deriving the provisional balance point, the output distribution determining unit 36 determines which one of the hydraulic output and the turning output is set as the priority output (step S13). For example, the output distribution determination unit 36 performs this determination based on the output of the priority output setting unit 33.

  When it is determined that the hydraulic output is set as the priority output (when the hydraulic pressure is prioritized) (hydraulic output in step S13), the output distribution determination unit 36 sets the temporary hydraulic output at the temporary balance point to the hydraulic priority priority lower limit value. It is determined whether it is below (step S14). The hydraulic pressure priority lower limit is a minimum hydraulic output value to be maintained when hydraulic priority is given, and is stored in advance in, for example, a storage medium. As a result, the hydraulic pressure output when the hydraulic pressure is prioritized is set so as not to fall below the lower limit value when the hydraulic pressure is prioritized as long as the total calculated force exceeds the reference value. This is to maintain a large output that the operator wants to prioritize. Note that the hydraulic pressure priority lower limit value may be calculated in real time.

  Therefore, when it is determined that the provisional hydraulic pressure output is lower than the lower limit value at the time of hydraulic priority (YES in step S14), the output distribution determination unit 36 adopts the output distribution indicated by the hydraulic pressure priority limit point (step S15). The oil pressure priority limit point corresponds to a provisional balance point having the oil pressure priority lower limit value as the provisional oil pressure output.

  If it is determined that the temporary hydraulic output is equal to or greater than the lower limit value at the time of hydraulic priority (NO in step S14), the output distribution determining unit 36 employs the output distribution indicated by the temporary balance point at that time (step S16).

  Here, with reference to FIG. 7, the transition of the ideal balance point and the provisional balance point when the hydraulic pressure is prioritized will be described. FIG. 7 is a graph showing an example of transition of the ideal balance point and provisional balance point when hydraulic pressure is prioritized. After the boom lever is fully operated, the operation of the turning lever is started and the operation amount is gradually increased. It shows the transition when going. In FIG. 7, the ideal balance points are point P1 (required hydraulic power output 100%: required turning output 0%, hereinafter both values are shown similarly), point P2 (100%: 10%), point P3 (100%). : 20%), point P4 (100%: 60%), point P5 (100%: 80%) in this order, and the provisional balance point also changes accordingly. The provisional balance point Q4 corresponds to a hydraulic pressure priority limit point Qh, and the provisional hydraulic output H4 of the provisional balance point Q4 corresponds to a hydraulic pressure priority lower limit value Ht. The ideal balance point Pr is a point when the required hydraulic pressure output and the required turning output are both equal to 100 [%] (reference ideal balance point), and the temporary balance point Qr corresponds to the ideal balance point Pr ( Standard provisional balance point). Further, the hydraulic pressure priority limit point Qh is set such that the hydraulic pressure priority lower limit value Ht as the temporary hydraulic output is larger than the temporary hydraulic output corresponding to the temporary balance point Qr. Further, the hydraulic pressure priority limit point Qh may be set at a position farther from the temporary balance point Qr as the interval between the boom lever operation start time and the swing lever operation start time becomes larger.

  As shown in FIG. 7, when the ideal balance point changes from the point P1 (100%: 0%) to the point P4 (100%: 60%), the provisional balance point changes from the point Q1 to the point Q4, and the hydraulic priority limit is reached. It reaches point Qh. Therefore, the provisional hydraulic output and the provisional turning output indicated by each of the provisional balance points Q1 to Q4 are employed as the output distribution of the hydraulic output and the turning output.

  However, even if the ideal balance point changes from the point P4 (100%: 60%) to the point P5 (100%: 80%), the provisional balance point does not change from the point Q4 to the point Q5 but remains at the point Q4. This is because the transition to the point Q5 causes the provisional hydraulic pressure output to fall below the hydraulic pressure priority lower limit value Ht. Therefore, the provisional hydraulic output and the provisional turning output indicated by the provisional balance point Q4 as the oil pressure priority limit point Qh are employed as the output distribution of the hydraulic output and the turning output.

  Returning to FIG. If it is determined that the turning output is set as the priority output (turning priority time) (turning output in step S13), the output distribution determining unit 36 determines that the provisional turning output of the temporary balance point has the lower limit value during turning priority. It is determined whether it is below (step S17). The turning priority lower limit value is a minimum turning output value that should be maintained when turning priority, and is a value stored in advance in a storage medium, for example. Thereby, the turning output at the time of turning priority is set so as not to fall below the lower limit value at the time of turning priority as long as the combined calculation force exceeds the reference value. This is to maintain a large output that the operator wants to prioritize. The turning priority lower limit value may be calculated in real time.

  Therefore, when it is determined that the provisional turning output is below the turning priority lower limit value (YES in Step S17), the output distribution determination unit 36 adopts the output distribution indicated by the turning priority time limit point (Step S18). The turning priority limit point corresponds to a provisional balance point having the turning priority lower limit value as a provisional turning output.

  If it is determined that the temporary turning output is equal to or greater than the turning priority lower limit value (NO in step S17), the output distribution determining unit 36 employs the output distribution indicated by the temporary balance point at that time (step S16).

  Here, with reference to FIG. 8, the transition of the ideal balance point and the temporary balance point at the time of turning priority will be described. FIG. 8 is a graph showing an example of the transition of the ideal balance point and the temporary balance point when turning is prioritized. After the lever is fully operated, the operation of the boom lever is started and the operation amount is gradually increased. It shows the transition when going. In FIG. 8, the ideal balance points are point P6 (required hydraulic output 0%: required turning output 100%), point P7 (10%: 100%), point P8 (20%: 100%), point P9 (60%: 100%) and point P10 (80%: 100%) in this order, and the provisional balance point also changes accordingly. The provisional balance point Q9 corresponds to the turning priority limit point Qs, and the provisional turning output S9 of the provisional balance point Q9 corresponds to the turning priority lower limit St. Further, the turning priority limit point Qs is set so that the turning priority lower limit St as the provisional turning output is larger than the provisional turning output corresponding to the provisional balance point Qr. Further, the turning priority limit point Qs may be set to a position farther from the provisional balance point Qr as the interval between the start of the operation of the turn lever and the start of the operation of the boom lever is larger.

  As shown in FIG. 8, when the ideal balance point changes from the point P6 (0%: 100%) to the point P9 (60%: 100%), the provisional balance point changes from the point Q6 to the point Q9 and the turning priority limit is reached. The point Qs is reached. Therefore, the temporary hydraulic output and the temporary turning output indicated by each of the temporary balance points Q6 to Q9 are adopted as the output distribution of the hydraulic output and the turning output.

  However, even if the ideal balance point changes from the point P9 (60%: 100%) to the point P10 (80%: 100%), the provisional balance point does not change from the point Q9 to the point Q10 but remains at the point Q9. This is because when the transition is made to the point Q10, the provisional turning output becomes lower than the turning priority lower limit value St. Therefore, the provisional hydraulic output and the provisional turning output indicated by the provisional balance point Q9 as the turning priority limit point Qs are employed as the output distribution of the hydraulic output and the turning output.

  The output distribution determining unit 36 determines that both the hydraulic output and the turning output are set as priority outputs, or determines that neither the hydraulic output and the turning output are set as priority outputs. The output distribution indicated by the provisional balance point at that time may be employed. In this case, the temporary balance point may be movable to the reference temporary balance point Qr beyond the hydraulic pressure priority limit point or the turning priority limit point.

  Returning to FIG. When it is determined that the combined calculation force is equal to or less than the reference value (NO in step S11), the output distribution determination unit 36 employs the output distribution indicated by the ideal balance point at that time without deriving the provisional balance point (step S12). ). This is because the sum of the hydraulic pressure output and the turning output is less than the drive source output, so that it is not necessary to execute output restriction on the hydraulic output and the turning output.

  Next, a flow of another example of the output distribution determination process will be described with reference to FIG. The output distribution determination process in FIG. 9 is different from the output distribution determination process in FIG. 5 in having step S20 and step S21, but is common in other points. Therefore, description of common parts is omitted, and different parts are described in detail.

  After determining that the total calculated force exceeds the reference value (YES in step S11) and adopting the output distribution indicated by the hydraulic pressure priority limit point, provisional balance point, or turning priority limit point (steps S15, S16, or S18), the output distribution determination unit 36 determines whether or not the non-priority output is increased (step S20).

  When it is determined that the non-priority output is increasing (YES in Step S20), the output distribution determining unit 36 limits the amount of decrease in the priority output (Step S21). For example, when the turning lever is operated in the direction in which the turning output as the non-priority output increases when the hydraulic pressure has priority, the provisional balance point becomes the reference value boundary line BL in the direction in which the provisional hydraulic output decreases and the provisional turning output increases. Move up. At this time, the output distribution determination unit 36 limits, for example, the reduction amount of the temporary hydraulic output per unit time to a predetermined maximum fluctuation amount. This is to prevent the output that the operator wants to prioritize from suddenly decreasing. As a result, the amount of increase in provisional turning output per unit time is also limited.

  However, this is not the case when the priority output is actively reduced. For example, when the boom lever is operated in a direction in which the hydraulic output as the priority output decreases when the hydraulic pressure has priority, the output distribution determination unit 36 does not limit the decrease amount of the temporary hydraulic output per unit time with the maximum fluctuation amount. Then, output distribution is determined based on the hydraulic priority priority point or the provisional balance point. This is to reduce the hydraulic output according to the operator's intention.

  Even when it is determined that the non-priority output has not increased (NO in step S20), the output distribution determination unit 36 does not limit the amount of change in the non-priority output. For example, when the turning lever is operated in the direction in which the turning output as the non-priority output decreases when the hydraulic pressure has priority, the provisional balance point becomes the reference value boundary line BL in the direction in which the provisional hydraulic output increases and the provisional turning output decreases. Move up. At this time, the output distribution determining unit 36 determines the output distribution based on the provisional balance point without limiting the increase amount of the provisional hydraulic output per unit time by the predetermined maximum fluctuation amount. This is to reduce the turning output according to the intention of the operator. Further, it is not necessary to prevent an increase in hydraulic output that the operator wants to prioritize.

  Here, an example of a method for controlling the change amount of the priority output when the non-priority output changes will be described with reference to FIG. FIG. 10 is a graph showing an example of the transition of the ideal balance point and the temporary balance point when the non-priority output (hydraulic output) changes when turning is prioritized, and the turning lever is operated with the full lever and the boom lever is operated with the half lever. The transition when the operation amount of the boom lever is changed from the state is shown.

  In FIG. 10, when the boom lever is operated in a direction in which the hydraulic pressure increases when turning is prioritized, the ideal balance point is from point P11 (required hydraulic output 30%: required turning output: 100%) to point P12 (50%: 100). %), And the provisional balance point changes from point Q11 to point Q12 accordingly.

  At this time, the temporary turning output decreases from S11 [%] to S12 [%], and the reduction amount of the temporary turning output is represented by ΔS1. Since this reduction amount ΔS1 is larger than the maximum fluctuation amount ΔT, the output distribution determination unit 36 limits the reduction amount of the provisional turning output by the maximum fluctuation amount ΔT and sets the final turning output to S14 (= S12−ΔT) [%. ]. Further, the output distribution determination unit 36 derives a point Q14 on the reference value boundary line BL corresponding to the turning output S14 [%], and further derives a hydraulic output H14 [%] corresponding to the point Q14. As described above, when the non-priority output increases, the output distribution determination unit 36 derives the respective output distributions of the hydraulic output and the turning output by limiting the decrease amount of the priority output in each control cycle with the maximum fluctuation amount. . This is to prevent the output that the operator wants to prioritize from suddenly decreasing.

  In FIG. 10, when the boom lever is operated in a direction in which the hydraulic output decreases when turning is prioritized, the ideal balance point changes from point P11 (30%: 100%) to point P13 (10%: 100%). Accordingly, the provisional balance point changes from point Q11 to point Q13.

  At this time, the provisional turning output increases from S11 [%] to S13 [%], and the increase amount of the provisional turning output is represented by ΔS2. Although this increase amount ΔS2 is larger than the maximum fluctuation amount ΔT, the output distribution determination unit 36 does not limit the increase amount of the provisional turning output with the maximum fluctuation amount ΔT, and uses the turning output S13 [%] as it is as the final turning output. And Further, the output distribution determining unit 36 derives the hydraulic output H13 [%] from the provisional balance point Q13 at that time. As described above, when the non-priority output decreases, the output distribution determination unit 36 does not limit the increase amount of the priority output in each control cycle with the maximum fluctuation amount, but based on the provisional balance point at that time. Thus, the output distribution of each of the hydraulic output and the swing output is derived. This is to reduce the non-priority output according to the intention of the operator. Moreover, it is not necessary to prevent the priority output from increasing.

  As described above, the shovel according to the embodiment of the present invention executes at least one output restriction when the sum of the hydraulic output and the turning output exceeds the drive source output. Then, when executing the output restriction, the hydraulic output or the turning output is set as the priority output based on the detection information or the input information, and the output distribution of each of the hydraulic output and the turning output is determined based on the setting. The output distribution that is set as the priority output is higher than the output distribution when the priority output is not set or higher than the predetermined reference output distribution. For example, as long as the combined calculation force exceeds the reference value, the output distribution of the hydraulic output when the hydraulic pressure is prioritized is higher than the output distribution of the hydraulic output when the turning is prioritized, or corresponds to the reference provisional balance point Qr (see FIG. 7). It is higher than the output distribution of hydraulic pressure output (lower limit value Ht when hydraulic pressure is prioritized). As long as the combined calculation force exceeds the reference value, the output distribution of the turning output at the time of turning priority is higher than the output distribution of the turning output at the time of hydraulic priority, or corresponds to the reference provisional balance point Qr (see FIG. 8). It is higher than the output distribution of the turning output (turning priority lower limit value St). Therefore, the operator's intention can be more appropriately reflected in the distribution of output power. As a result, when excavating a position higher than the vehicle body position, output power distribution suitable for the work content can be realized, such as giving priority to turning output.

  Further, when executing the output restriction, the shovel according to the embodiment of the present invention sets the hydraulic output or the turning output as the priority output based on the operation input related to the hydraulic output and the operation input related to the turning output. For example, when the swing lever is operated first among the swing lever and the boom lever, the swing output is set as a priority output, and when the boom lever is operated first, the hydraulic output is set as a priority output.

  In addition, when the operation input related to the one set as the priority output is stopped, the setting of the priority output is reset. For example, when the turning lever is returned to the neutral position when the turning output is set as the priority output, or when the boom lever is returned to the neutral position when the hydraulic output is set as the priority output. The priority output setting is reset.

  Further, when the output distribution of the one not set as the priority output is increased, the reduction rate of the output distribution set as the priority output is limited. For example, even when the turning lever is operated in a direction in which the turning output as the non-priority output increases when the hydraulic pressure has priority, the amount of decrease in the hydraulic output as the priority output is limited by a predetermined maximum fluctuation amount. This is to prevent the output that the operator wants to prioritize from suddenly decreasing.

  Further, the increase rate of the output distribution of the one set as the priority output is not limited. For example, even when the turning lever is operated in a direction in which the turning output as the non-priority output decreases when the hydraulic pressure has priority, the increase amount of the temporary hydraulic output per unit time is not limited by the predetermined maximum fluctuation amount. This is to reduce the turning output according to the intention of the operator. Further, it is not necessary to prevent an increase in hydraulic output that the operator wants to prioritize.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, in the above-described embodiment, the hydraulic output is a maximum of 100 [kW], the turning output is a maximum of 100 [kW], and the engine output is a maximum of 100 [kW]. ], The maximum value of the hydraulic output is set between 90 [kW] and 60 [kW], and the maximum value of the turning output is set between 30 [kW] and 60 [kW]. May be. Alternatively, as long as the combined calculation force does not exceed the maximum 120 [kW] of the engine output, the maximum value of the hydraulic output is set between 90 [kW] and 30 [kW], and the maximum value of the turning output is 30 [kW]. kW] to 90 [kW] may be set.

  In the above-described embodiment, the drive source output is the engine output, but the drive source output may be, for example, the sum of the engine output and the capacitor output. In this case, the capacitor output is supplied to the turning electric motor 21 and the motor generator 12 that assists the engine 11.

  DESCRIPTION OF SYMBOLS 1 ... Lower traveling body 1A, 1B ... Hydraulic motor 2 ... Turning mechanism 3 ... Upper turning body 4 ... Boom 5 ... Arm 6 ... Bucket 7 ... Boom cylinder 8 ... arm cylinder 9 ... bucket cylinder 10 ... cabin 11 ... engine 12 ... motor generator 13 ... transmission 14 ... main pump 15 ... pilot pump 16 ... High pressure hydraulic line 17 ... Control valve 18 ... Inverter 19 ... Capacitor 20 ... Inverter 21 ... Turning motor 22 ... Resolver 23 ... Mechanical brake 24 ... Swivel transmission 25 ... Pilot line 26 ... Operating device 26A, 26B ... Lever 26C ... Pedal 27,28 ... Hydraulic line 2 ... Pressure sensor 30 ... Controller 31 ... Hydraulic output estimation unit 32 ... Turning output estimation unit 33 ... Priority output setting unit 34 ... Pump horsepower command generation unit 35 ... Turning command generation Unit 36 ... Output distribution determination unit 120 ... Power storage system

Claims (6)

A construction machine that executes at least one output restriction when the sum of the hydraulic output and the turning output exceeds the drive source output,
When executing the output restriction, the hydraulic output or the turning output is set as the priority output based on the detection information or the input information, and each output distribution of the hydraulic output and the turning output is determined based on the setting, and the priority output is set. The set output distribution is higher than the output distribution when not set as the priority output, or higher than the predetermined reference output distribution,
Construction machinery. Set hydraulic output or turning output as priority output based on operation input related to hydraulic output and operation input related to turning output,
The construction machine according to claim 1. The priority output setting is reset when the operation input related to the one set as the priority output is canceled.
The construction machine according to claim 1 or 2. When increasing the output distribution of the one not set as the priority output, the rate of decrease of the output distribution set as the priority output is limited.
The construction machine according to any one of claims 1 to 3. The drive source output is the sum of the engine output and the capacitor output.
The construction machine according to any one of claims 1 to 4. The rate of increase in output distribution for the one set as priority output is not limited,
The construction machine according to any one of claims 1 to 5.

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