Rotation control device, rotation control method, and construction machine

The present invention relates to an electric swivel excavator and a swivel control method for the electric swivel excavator.

In recent years, a hybrid type electric swivel excavator has been developed in which a swivel body is driven by an electric motor and a work machine or a traveling body is driven by a hydraulic actuator (see, for example, Patent Document 1). In such an electric swivel excavator, since the swivel body is swiveled by an electric motor, the swivel body moves even if the swivel body is swiveled at the same time as the flood-driven boom or arm ascending motion. It is not affected by the ascending motion. Therefore, as compared with a general hydraulic excavator in which the swivel body is also hydraulically driven, the loss in the control valve or the like can be reduced, and the energy efficiency is good.

By the way, in a normal hydraulic excavator, the swivel body is also driven by the flood control from the hydraulic pump like the working machine, and this hydraulic pump is driven by the engine. Therefore, when the amount of fuel supplied to the engine is changed to adjust the rotation speed, the discharge flow rate of the hydraulic oil from the hydraulic pump also changes, and the turning speed of the swivel body changes. That is, if the fuel dial is narrowed down and the amount of fuel supplied is reduced, the engine speed decreases, but the turning speed of the swivel body also slows down accordingly. On the contrary, when the fuel supply amount is increased by operating the fuel dial, the engine speed increases and the turning speed of the swivel body also increases.

In the hydraulic excavator, the engine speed is intentionally adjusted by changing the fuel supply amount not only by operating the fuel dial but also by operating the mode changeover switch for changing the work mode. The work mode includes, for example, an active mode, an economy mode, a breaker mode, a lift mode, and the like in descending order of engine speed, and a mode corresponding to the work at that time is selected.

<p><patcit num="1"><text>Japanese Unexamined Patent Publication No. 2001-11897</text></patcit></p>

<p> However, according to the electric swivel excavator described in Patent Document 1, since the swivel body is not driven by flood control and swivels at a constant swivel speed regardless of the engine speed, the hydraulic excavator to the electric swivel excavator There is a problem that the operator who has switched to the engine feels uncomfortable with the movement of the swivel body, which does not change according to the engine speed.</p><p> In addition, the change in the turning speed of the hydraulic excavator also occurs when a working machine such as a boom or an arm is driven during turning. This is because the hydraulic oil used to swivel the swivel body is also used to drive the work equipment, and the swivel speed drops. Even in such a case, the electric swivel excavator has a constant swivel speed, which also causes a sense of discomfort.</p><p> An object of the present invention is to provide an electric swivel excavator that can prevent the operator from feeling uncomfortable even when the swivel body is changed from hydraulic drive to electric drive, and a swivel control method for the electric swivel excavator.</p>

<p> An electric swivel excavator including a hydraulically driven work machine, an electrically driven swivel body, and a swivel control device for controlling the swivel body. The turning control device is The turning speed of the turning body<u style="single">Maximum speed</u>Gain selector switch to switch between A gain switching state determination unit that determines the setting state of this gain changeover switch, It is characterized by including a target speed command generating means for generating a target speed command value of the swivel body based on the determination result of the gain switching state determination unit.</p><p> In the present invention, it is preferable that the gain changeover switch can be set to a different turning speed when the working machine is raised to a predetermined height during a predetermined turning operation time. In the present invention<u style="single">When the turning speed of the turning body is selected by the gain changeover switch, a turning speed command is generated in preference to other settings.</u>Is preferable.</p><p> The electric swivel excavator of the present invention An electric swivel excavator including a hydraulically driven work machine, an electrically driven swivel body, and a swivel control device for controlling the swivel body. The turning control device is The turning speed of the turning body<u style="single">Maximum speed</u>With an adjustment dial that continuously changes A judgment unit that determines the setting status of this adjustment dial, It is characterized by including a target speed command generating means for generating a target speed command value of the swivel body based on the determination result of the determination unit.<u style="single">In the present invention, when the turning speed of the turning body is selected by the adjusting dial, a turning speed command is generated in preference to other settings.</u>Is preferable.</p><p> The electric swivel excavator of the present invention<u style="single">A boom driven by the supply of pressure oil from a hydraulic pump driven by an engine,</u>An electric excavator including an electrically driven swivel body and a swivel control device for controlling the swivel body. A gain changeover switch for switching the turning speed of the turning body is provided.<u style="single">At the time of the combined operation in which the boom raising operation and the turning operation of the turning body are performed at the same time, the turning speed of the turning body is switched in a plurality of stages by the gain changeover switch, and the operation amount of the turning operation lever based on the selected turning speed is adjusted. Generate the corresponding turning speed command</u>It is characterized by that.<u style="single">In the present invention, when the turning speed of the turning body is selected by the gain changeover switch, a turning speed command is generated in preference to other settings.</u>Is preferable.</p><p> The swivel control method of the electric swivel excavator of the present invention<u style="single">A boom driven by the supply of pressure oil from a hydraulic pump driven by an engine,</u>A swivel control method for an electric swivel excavator including an electrically driven swivel body and a swivel control device for controlling the swivel body.<u style="single">A procedure for switching the turning speed of the turning body in a plurality of stages by a gain changeover switch during a combined operation in which the boom raising operation and the turning operation of the turning body are performed at the same time.</u><u style="single">Procedure for generating a turning speed command corresponding to the operating amount of the turning operation lever based on the selected turning speed</u>Is characterized by carrying out.</p><p> In the present invention<u style="single">When the turning speed of the turning body is selected by the gain changeover switch, a turning speed command is generated in preference to other settings.</u>Is preferable.</p>

<p> According to the present invention, it is electrically operated according to the setting state by the fuel supply amount setting means such as the fuel dial, the switching state by the work mode switching means such as the mode changeover switch, or the operation amount of the work equipment lever. Since the target speed command signal for the motor is generated and the turning speed of the turning body is changed accordingly, when the engine speed becomes low due to the state of each means, the turning speed of the turning body is reduced accordingly. When the engine speed becomes high, the turning speed can be increased, and further, the turning speed can be lowered even when the working machine is operated during turning. Therefore, it is possible to obtain almost the same operability as when the swivel body is swiveled by a normal hydraulic system, and there is no need to worry about feeling uncomfortable.</p>

<figref num="1">The plan view which shows the construction machine which concerns on 1st Embodiment of this invention.</figref><figref num="2">The block diagram for demonstrating the turning control device mounted on the construction machine which concerns on the 1st Embodiment.</figref><figref num="3">The block diagram for demonstrating the throttle command generation means of the turning control device which concerns on 1st Embodiment.</figref><figref num="4">The figure which shows the relationship between the setting of the fuel dial and the engine idle speed in the 1st Embodiment.</figref><figref num="5">The figure which shows the relationship between the throttle command value and a turning speed coefficient in the 1st Embodiment.</figref><figref num="6">The figure which shows the relationship between the engine speed and the engine torque in the 1st Embodiment.</figref><figref num="7">The figure which shows the relationship between the working machine lever operation amount and the turning speed coefficient in the 1st Embodiment.</figref><figref num="8">The block diagram for demonstrating the rate coefficient generation means of the turning control apparatus which concerns on 1st Embodiment.</figref><figref num="9">The figure which shows the relationship between the swivel lever operation amount and the swivel speed in the 1st Embodiment.</figref><figref num="10">The figure which shows the relationship between the time required for turning in the 1st Embodiment, a boom height, and a turning position.</figref><figref num="11">The figure for demonstrating the work which has a different turning amount in the 1st Embodiment.</figref><figref num="12">The flowchart which shows the generation flow of the turning speed coefficient in the turning control device which concerns on the 1st Embodiment.</figref><figref num="13">The block diagram for demonstrating the turning control device mounted on the construction machine which concerns on 2nd Embodiment of this invention.</figref>

[First Embodiment] [1-1] Overall configuration Hereinafter, the first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing an electric swivel excavator (construction machine) 1 according to the present embodiment, and FIG. 2 is a block diagram for explaining a control device (swivel control device) 50 mounted on the electric swivel excavator 1. is there.

In FIG. 1, the electric swivel excavator 1 includes a swivel body 4 installed on a track frame constituting the lower traveling body 2 via a swing circle 3, and the electric motor 5 in which the swivel body 4 meshes with the swing circle 3. Driven by turning. Although not shown, the power source of the electric motor 5 is a generator mounted on the swing body 4, and this generator is driven by the engine 12.

The swivel body 4 is provided with a boom 6, an arm 7, and a bucket 8 operated by a hydraulic cylinder (not shown), respectively, and the working machine 9 is composed of these. The hydraulic source of each hydraulic cylinder is a hydraulic pump driven by the engine 12. Therefore, the electric swivel excavator 1 is a hybrid construction machine including a hydraulically driven working machine 9 and an electrically driven swivel body 4.

According to this electric swivel excavator 1, as shown in FIG. 2, a lever signal corresponding to the tilt angle is output to the control device 50 from the swivel lever 10 (usually also used as a work equipment lever for operating the arm 7). To. Specifically, this lever signal is first input to the speed command generation means 51 of the control device 50, where it is converted into a reference target speed. The reference target speed is the turning speed coefficient generated based on the setting input from the fuel dial (fuel supply amount setting means) 13, the mode changeover switch (work mode changeover means) 14, the gain changeover switch 15, the work equipment lever 16, etc. By multiplication, the speed is changed to the target speed command value of the swivel body 4, and the speed is output to an inverter (not shown).

The turning speed coefficient adjusts the magnitude of the target speed command value. For example, when the turning speed coefficient is determined to be a value exceeding "1", the product of this value and the reference target speed is used. , The target speed command value increases, and the rotation speed of the electric motor 5 increases. On the contrary, if the value is determined to be smaller than "1" (however, larger than "0"), the target speed command value becomes smaller, so that the rotation speed of the electric motor 5 decreases.

The inverter compares the fed-back actual speed of the electric motor 5 with the target speed command value, and sets the motor torque command value according to the deviation. Then, this torque command value is converted into a current value and a voltage value, and the electric motor 5 is controlled to be driven at the target speed. Therefore, if the actual speed does not increase even if the swivel lever 10 is tilted greatly, the torque output is increased and controlled so as to approach the target speed. However, such control is speed control by general P (Proportional: proportional) control.

[1-2] Control device configuration and relationship with each setting input Next, the configuration of the control device 50 and the relationship with each setting input means will be described with reference to FIGS. 2 to 11. In FIG. 2, the control device 50 generates a target speed command value of the swivel body 4 based on setting inputs from the swivel lever 10, the fuel dial 13, the mode selector switch 14, the gain selector switch 15, the work equipment lever 16, and the like. .. For this purpose, the control device 50 includes a speed command generating means 51, a throttle command generating means 52, a working machine lever command generating means 53, a gain changeover switch command generating means 54, a speed coefficient generating means 55, and a target speed command generating means 56. ing. The control device 50 also controls the amount of fuel supplied (injection) to the engine 12.

The speed command generating means 51 first generates a reference target speed of the swivel body 4 based on the tilt angle of the swivel lever 10. The reference target speed generated here is a value that is the base of the target speed command value, and when the turning speed coefficient is "1", the reference target speed is output to the inverter as the target speed command value as it is.

The throttle command generating means 52 generates a turning speed coefficient according to the set state of the fuel dial 13 and the mode changeover switch 14, and outputs the turning speed coefficient to the speed coefficient generating means 55. That is, the throttle command generation means 52 generates a turning speed coefficient in consideration of the engine speed, which is a factor for changing the turning speed of the turning body in the hydraulic excavator. Therefore, as shown in FIG. 3, the throttle command generation means 52 includes a throttle command value generation unit 521, a fuel dial coefficient generation unit 522, a mode changeover switch coefficient generation unit 523, and a throttle command coefficient generation unit 524. ..

The throttle command value generation unit 521 generates a throttle command value according to the setting state of the fuel dial (fuel supply amount setting means) 13 in order to control the fuel supply (injection) amount to the engine 12. Then, the generated throttle command value is output to the governor motor and used for rack position control in a fuel injection pump (not shown).

The setting state of the fuel dial 13 can be changed steplessly or stepwise from the Li (low idle) side to the Hi (high idle) side. If the fuel dial 13 is rotated to the Hi side, FIG. 4 As shown in, the throttle command value generator 521 generates a larger throttle command value, so that a higher idle speed is set in the engine 12. On the contrary, if it is rotated to the Li side, the throttle command value generation unit 521 generates a smaller throttle command value, so that a lower idle speed is set.

The fuel dial coefficient generation unit 522 generates the first turning speed coefficient based on the throttle command value generated by the throttle command value generation unit 521. In the present embodiment, the first turning speed coefficient is generated based on the relationship between the throttle command value and the turning speed coefficient shown in FIG. That is, when the fuel dial 13 is set to the Hi side and the engine speed is increased, the throttle command value generated by the throttle command value generation unit 521 becomes large, so that the first turning speed coefficient becomes large. On the other hand, when the engine speed is lowered by setting it on the Li side, the throttle command value becomes smaller, so that the first turning speed coefficient becomes smaller.

The mode changeover switch coefficient generation unit 523 generates a second turning speed coefficient based on the setting mode of the mode changeover switch 14, and outputs the second turning speed coefficient to the throttle command coefficient generation unit 524. In the present embodiment, the value of the turning speed coefficient corresponding to each setting mode is set in advance, and the mode changeover switch coefficient generation unit 523 selects the turning speed coefficient according to the setting mode.

The mode changeover switch 14 is a switch for switching the work mode. For example, the A mode for working at a high engine speed, the B mode for working at a low speed, and the C mode can be selected. Is. Specifically, according to the mode selector switch 14, as shown in FIG. 6, when the A mode is selected, the idling speed of the engine 12 is held on the high rotation speed side of the A1, and the B and C modes are selected. The engine 12 is driven by the idling speeds of, B1 and C1.

The throttle command coefficient generation unit 524 uses a first turning speed coefficient generated by the fuel dial coefficient generating unit 522 and a second turning speed coefficient generated by the mode selector switch coefficient generating unit 523 to generate a third. A turning speed coefficient is generated and output to the speed coefficient generating means 55. Specifically, the throttle command coefficient generation unit 524 multiplies the first turning speed coefficient and the second turning speed coefficient to generate a third turning speed coefficient. Therefore, the third turning speed coefficient is a value that reflects the settings of the fuel dial 13 and the mode selector switch 14.

Returning to FIG. 2, the working machine lever command generating means 53 generates a fourth turning speed coefficient based on the tilt amount of the working machine lever 16, and outputs the fourth turning speed coefficient to the speed coefficient generating means 55. Specifically, a fourth turning speed coefficient is generated by the relationship between the operating amount of the work equipment lever 16 shown in FIG. 7 and the turning speed coefficient. Therefore, when the operating amount of the work equipment lever 16 is large, a smaller turning speed coefficient is generated, and when the operating amount is small, a larger turning speed coefficient is generated.

The gain changeover switch command generation means 54 generates a fifth turning speed coefficient based on the setting of the gain changeover switch 15 and outputs the fifth turning speed coefficient to the speed coefficient generation means 55. Here, the gain changeover switch 15 is a switch for arbitrarily setting the turning speed coefficient regardless of the throttle command value. In the present embodiment, for example, high-speed turning, medium-speed turning, low-speed turning, extremely low-speed turning, etc. are performed. You can select it. Therefore, when high speed turning is selected by the gain changeover switch 15, the gain changeover switch command generation means 54 calculates a larger turning speed coefficient, and when low speed turning is selected, a smaller turning speed coefficient is calculated.

The speed coefficient generating means 55 is set to the third turning speed coefficient generated by the throttle command coefficient generating unit, the fourth turning speed coefficient generated by the working machine lever command generating means 53, and the gain changeover switch 15. Based on this, the final turning rate coefficient is generated. Therefore, as shown in FIG. 8, the speed coefficient generating means 55 includes a speed coefficient determination unit 551, a speed coefficient selection unit 552, a gain switching state determination unit 553, and a speed coefficient final selection unit 554.

The speed coefficient determination unit 551 has a third turning speed coefficient generated by the throttle command coefficient generating unit 524 of the throttle command generating means 52 and a fourth turning speed coefficient generated by the working machine lever command generating means 53. Judge the magnitude relationship. The speed coefficient selection unit 552 selects the smaller value of the third turning speed coefficient and the fourth turning speed coefficient according to the determination result of the speed coefficient determination unit 551.

That is, when it is determined that the third turning speed coefficient generated by the throttle command coefficient generation unit 524 is smaller than the fourth turning speed coefficient generated by the work equipment lever command generation means 53, the speed coefficient selection unit 552 selects a third turning rate coefficient. Therefore, as will be described later, when the speed coefficient final selection unit 554 selects the selection value in the speed coefficient selection unit 552 as the final turning speed coefficient, the turning speed of the swivel body 4 with respect to the swivel lever operation amount is the second. It will change according to the characteristics of the turning speed coefficient of 3. That is, as shown in FIG. 9, the swivel speed of the swivel body 4 with respect to the swivel lever operation amount changes according to the settings of the fuel dial 13 and the mode changeover switch 14.

In FIG. 9, the Hi side indicates the turning speed when the fuel dial 13 is opened most to the Hi side, and the Li side indicates the turning speed when the fuel dial 13 is narrowed down to the most Li side. Shows the turning speed of. Further, the relationship between the swivel lever operation amount and the swivel speed when the mode changeover switch 14 is set in each of the modes A to C is shown. As described above, if the lever operation amount is the same, the turning speed of the swivel body 4 becomes maximum when the fuel dial 13 is opened most to the Hi side, and the turning speed becomes minimum when the fuel dial 13 is throttled to the most Li side. In addition, the characteristics of the turning speed for each mode of the mode selector switch 14 are set so as to fall into the region between them, and the A mode with a high engine speed has a higher turning speed than the B mode, and the B mode. Has a higher turning speed than C mode.

On the other hand, when it is determined that the fourth turning speed coefficient generated by the working machine lever command generating means 53 is smaller than the third turning speed coefficient generated by the throttle command coefficient generating unit 524, the speed coefficient selection unit The 552 selects a fourth turning rate coefficient. Therefore, as will be described later, when the speed coefficient final selection unit 554 selects the selection value in the speed coefficient selection unit 552 as the final turning speed coefficient, the turning speed coefficient in this case is as shown in FIG. In addition, the value is determined by the operating amount of the work equipment lever 16 regardless of the operating amount of the swivel lever 10.

Returning to FIG. 8, the gain switching state determination unit 553 determines whether or not the gain switching switch 15 is set. The speed coefficient final selection unit 554 has a fifth turning speed coefficient generated by the gain changeover switch command generation means 54 and a turning speed selected by the speed coefficient selection unit 552 according to the determination result of the gain switching state determination unit 553. One of the coefficients is selected and output as the final turning speed coefficient. That is, when no setting is made by the gain changeover switch 15, the speed coefficient final selection unit 554 selects the turning speed coefficient selected by the speed coefficient selection unit 552 as described above.

On the other hand, when it is determined that some setting has been made in the gain changeover switch 15, the setting of the gain changeover switch 15 has priority, and the speed coefficient final selection unit 554 is generated by the gain changeover switch command generation means 54. The turning speed coefficient is selected and output as the final turning speed coefficient value. In other words, even if the rotation speed of the engine 12 is not changed, the turning speed can be changed to high speed turning, medium speed turning,<u style="single">Low speed turning</u>、<u style="single">Extremely low speed turning</u>It becomes possible to adjust to.

It should be noted that such switching by the gain changeover switch 15 is performed, for example, when performing the operations shown in FIGS. 10 and 11. In these figures, an example of switching between high-speed turning and low-speed turning is shown. When excavating using the electric swivel excavator 1, the position of excavation and the position of the transport vehicle 60 that transports the excavated soil are usually 90 ° deviated from each other in terms of the swivel angle of the swivel body 4 and 180 °. In many cases, they are off by °. However, the loading height (boom height) on the transport vehicle 60 is constant. Further, in consideration of workability, the work machine 9 (boom 6) is at the loading height position when the swivel body 4 is swiveled by 90 ° or 180 °, which is a lean movement. Therefore, when the transport vehicle 60 is in the position where it is turned 90 °, select low-speed turning, and when the transport vehicle 60 is in the position where it is turned 180 °, select high-speed turning and set the work machine 9 exactly. When it is raised to the loading height (t seconds later), the turning of the swivel body 4 is completed so that the work without unnecessary movement can be performed.

Also, by the gain selector switch 15.<u style="single">Extremely low speed turning</u>When is selected, an extremely low value is generated as the turning speed coefficient, and the turning speed can be extremely reduced. For example, according to such an extremely low speed turning, it is possible to turn the swivel body 4 within the extremely low speed region shown by the hatched portion in FIG. That is, such control is like the curve shown by the dotted line, and even if the swivel lever 10 is tilted greatly, the swivel speed does not increase so much, so that the work equipment 9 is positioned in the swivel direction with high accuracy. It is effective for ultra-slow speed operation.

In this way, in the speed coefficient generating means 55 of the control device 50, the turning speed coefficient is generated in a complex manner by the various input signals. For this reason, a turning speed coefficient that is finely adjusted according to each setting is generated, and finally, a target speed command that gives an operation feeling that is almost the same as that of a conventional hydraulic excavator and does not cause discomfort. A value is generated.

Returning to FIG. 2, the target speed command generating means 56 generates a target speed command value based on the reference target speed generated by the speed command generating means 51 and the turning speed coefficient generated by the speed coefficient generating means 55. .. Specifically, the target speed command generation means 56 generates a target speed command value by multiplying the reference target speed and the turning speed coefficient.

[1-3] Flow of generating the turning speed coefficient by the speed coefficient generating means Next, based on FIG. 12, the flow of generating the turning speed coefficient by the speed coefficient generating means 55, and among them, the flow when no setting is made by the gain changeover switch 15, which is characteristic of the present embodiment, will be described. ..

First, the throttle command value generation unit 521 of the throttle command generation means 52 reads the setting state of the fuel dial 13 (step 11: step is simply abbreviated as "S" on the drawing and in the following description), and according to the setting state. Generates the throttle command value (S12). The fuel dial coefficient generation unit 522 generates the first turning speed coefficient based on the throttle command value generated by the throttle command value generation unit 521 (S13).

Further, the mode changeover switch coefficient generation unit 523 reads the setting state of the mode changeover switch 14 (S14) and generates a second turning speed coefficient according to the setting state (S15). Then, the throttle command coefficient generation unit 524 multiplies the first turning speed coefficient generated by the fuel dial coefficient generating unit 522 with the second turning speed coefficient generated by the mode changeover switch coefficient generating unit 523. Generate a third turn rate coefficient (S16)

On the other hand, the work machine lever command generation means 53 reads the operation amount of the work machine lever 16 (S17) and generates a fourth turning speed coefficient based on this value (S18). Then, in the speed coefficient determination unit 551 of the speed coefficient generating means 55, the third turning speed coefficient generated by the throttle command coefficient generating unit 524 is the fourth turning speed coefficient generated by the working machine lever command generating means 53. Determine if it is smaller (S19).

Here, when it is determined that the third turning speed coefficient is smaller than the fourth turning speed coefficient, the speed coefficient selection unit 552 selects the third turning speed coefficient (S20). On the other hand, when it is determined that the fourth turning speed coefficient is smaller than the third turning speed coefficient, the speed coefficient selection unit 552 selects the fourth turning speed coefficient (S21).

[1-4] Effect of this embodiment According to the present embodiment as described above, there are the following effects. That is, according to the control device 50 mounted on the electric swivel excavator 1, a swivel speed coefficient is generated according to the setting state of the fuel dial 13 and the switching state of the mode selector switch 14, thereby causing the swivel body 4 to generate a swivel speed coefficient. Since the turning speed can be changed, if the engine speed becomes low due to the operation of the fuel dial 13 or the mode selector switch 14, the turning speed of the turning body 4 can be reduced accordingly, and the engine speed can be reduced. When the number becomes high, the turning speed can be increased.

Further, since the turning speed coefficient can be changed according to the switching state of the gain changeover switch 15 and the operation amount of the work equipment lever 16, the turning body 4<u style="single">Turning speed</u>Even if you want to change the speed intentionally regardless of the rotation speed of the engine 12, you can change it arbitrarily by operating the gain selector switch 15, and even if you operate the work equipment 9 during turning, the turning speed should be reduced. Can be done.

Therefore, it is possible to obtain a ride quality that is almost the same as when the swivel body 4 is swiveled by a normal hydraulic type, and even if the conventional hydraulic excavator is switched to the electric swivel excavator 1, there is no worry of feeling any discomfort. There is.

[Second Embodiment] FIG. 13 shows a second embodiment of the present invention. In the present embodiment, the target speed command value is generated by limiting the upper limit of the reference target speed, instead of generating the target speed command value by multiplying the reference target speed and the turning speed coefficient. , Different from the first embodiment. Therefore, the control device 50 includes the speed command limit value setting means 57. Further, the processing content of the target speed command generation means 56 is different from that of the first embodiment.

The speed command limit value setting means 57 converts the turning speed coefficient generated by the speed coefficient generating means 55 into a speed command limit value with respect to the reference target speed. Here, the speed command limit value setting means 57 generates a speed command limit value by multiplying the maximum value of the preset target speed command value and the turning speed coefficient. Further, the target speed command generating means 56 limits the upper limit of the reference target speed generated by the speed command generating means 51 by the speed command limit value generated by the speed command limit value setting means 57, and sets the target speed command value. To do. Other configurations and flows are the same as those in the first embodiment, and description thereof will be omitted here.

According to the present embodiment as described above, the same effect as in the case of the first embodiment can be obtained without lowering the speed response in the low speed range.

The present invention is not limited to the above-described embodiment, but includes other configurations and the like capable of achieving the object of the present invention, and the following modifications and the like are also included in the present invention. For example, in the above embodiment, the gain changeover switch 15 is provided, and a turning speed coefficient corresponding to a selection such as high-speed turning, medium-speed turning, low-speed turning, and extremely low-speed turning is generated stepwise regardless of the engine speed. However, the auxiliary adjustment dial 17 as shown by the alternate long and short dash line is provided in Fig. 2, and the turning speed coefficient is continuously changed to continuously change the turning speed regardless of the engine speed. You may.

Further, both the gain changeover switch 15 and the auxiliary adjustment dial 17 may be provided, and the turning speed coefficient may be continuously finely changed within each speed range selected by the gain changeover switch 15.

In the above embodiment, the final turning speed coefficient is generated by multiplying or selecting a plurality of turning speed coefficients, but the present invention is not limited to this, and if the object of the present invention can be obtained, for example. It may be an average value. Further, in the above-described embodiment, complex generation is performed based on various input signals, but a value based on one type of single signal is selected from a plurality of input signals. May be good.

In the first embodiment, the final target speed command value is changed by multiplying the reference target speed by the turning speed coefficient, but the reference target speed itself is selectively selected from a plurality of settings. It may be a target speed command value.

The best configuration, method, and the like for carrying out the present invention are disclosed in the above description, but the present invention is not limited thereto. That is, the present invention is particularly illustrated and described primarily with respect to specific embodiments, but with respect to the embodiments described above, without departing from the scope of the technical idea and purpose of the present invention. In the detailed configuration of, those skilled in the art can make various modifications.

The present invention includes a hydraulically driven hydraulically driven work machine that raises excavated soil from an excavated position to a loading height position of a transport vehicle, an electrically driven swivel body, and a swivel control device that controls the swivel body. It can be used for electric swivel excavators.

1 ... Electric excavator (construction machinery), 4 ... Swivel, 5 ... Electric motor, 9 ... Work machine, 12 ... Engine, 15 ... Gain selector switch, 16.. .Working machine lever, 17 ... Auxiliary adjustment dial, 50 ... Control device (swivel control device), 56 ... Target speed command generation means, 553 ... Gain switching state determination unit.