JP7574163B2 - Operation control device for work vehicle - Google Patents

Description

The present invention relates to an operation control device for a work vehicle.

Hydraulic shovels (excavators) are known as working vehicles. Hydraulic shovels are configured to include a lower traveling body having left and right crawler mechanisms, an upper rotating body rotatably mounted on the lower traveling body, and a shovel device mounted in front of the upper rotating body. One such hydraulic shovel is known to include a power supply unit having a battery and an inverter, an electric motor that is driven by electricity from the power supply unit, a hydraulic pump that is driven by the electric motor, and multiple hydraulic actuators (hydraulic motors, hydraulic cylinders, etc.) that are operated by hydraulic oil discharged from the hydraulic pump, and these hydraulic actuators operate the crawler mechanism and shovel device, etc., to travel, perform excavation work, etc. (see, for example, Patent Document 1).

Such hydraulic actuators include a travel motor that operates the crawler mechanism, a rotation motor that rotates the upper rotating body, a boom cylinder, arm cylinder, bucket cylinder, and swing cylinder that operate the shovel device, and a blade cylinder that moves the blade up and down. The hydraulic pump supplies hydraulic oil to these actuators, and the operator operates the lever not only in a single operation that operates one of the hydraulic actuators when selected, but also in a combined operation that operates two or more hydraulic actuators in a combined manner. In view of this, Patent Document 1 discloses that the rotation of an electric motor is controlled according to the operating state and operation content of the operating device.

Patent No. 5371210

When driving a hydraulic pump with an electric motor, it is necessary to reduce the power consumption of the electric motor as much as possible due to factors such as battery capacity. For this reason, conventionally, control has been performed to reduce drive power by changing the drive rotation of the electric motor in response to the amount of operation of the control lever. However, at this time, due to requirements for the performance of the hydraulic pump, the drive speed of the hydraulic pump is required to be equal to or higher than the minimum required speed (for example, about 500 to 700 rpm). For this reason, in the region where the amount of operation of the control lever is small (fine operation region), even if the amount of oil required by the hydraulic actuator is small and the electric motor can be driven at a speed lower than the required speed, the electric motor is controlled to be driven at the minimum required speed required for the hydraulic pump.

This type of electric motor drive control is performed in the same way whether the operating lever is operated individually or in a combined manner. However, when a combined operation is performed, it is necessary to supply hydraulic oil to multiple hydraulic actuators, and the electric motor is controlled to be driven at a total motor rotation speed obtained by adding up the required rotation speeds corresponding to each operation. However, with this type of control, when the amount of operation of the combined operation is small (when in the fine operation range), the total motor rotation speed is the sum of the minimum required rotation speeds, which results in a problem that the motor rotation speed is higher than necessary and the power consumption of the electric motor increases.

The present invention was made in consideration of these problems, and aims to make it possible to suppress the power consumption of the electric motor by suppressing the motor drive rotation speed to the minimum necessary when the amount of operation is small during combined operations.

In order to achieve the above object, the operation control device according to the present invention is an operation control device for a work vehicle (e.g., hydraulic excavator 1 in the embodiments) equipped with a hydraulic operating device (e.g., crawler mechanism 15, upper rotating body 20, shovel device 30 in the embodiments), and is configured to include a plurality of hydraulic actuators (e.g., travel motors 16L, 16R, swing cylinder 34, boom cylinder 36, arm cylinder 37, bucket cylinder 38, blade cylinder 19 in the embodiments) for driving the hydraulic operating device, an operating device for selectively or in combination operating the plurality of hydraulic actuators to drive the hydraulic operating device, a hydraulic oil supply source that delivers hydraulic oil for driving the plurality of hydraulic actuators, and an oil discharge amount control device (e.g., controller 150 in the embodiments) for controlling the amount of oil discharged from the hydraulic oil supply source. Furthermore, the hydraulic oil supply source is composed of an electric motor (for example, the first electric motor M1 in the embodiment) and a hydraulic pump (for example, the first hydraulic pump P1 in the embodiment) driven by the electric motor, and the oil discharge amount control device is configured to control the amount of oil discharged from the hydraulic pump by controlling the rotation of the electric motor in response to the operation of the operating device. When the operating device is operated independently to selectively operate one of the plurality of hydraulic actuators, an operation-corresponding motor speed corresponding to the operation amount of the operating device is set, and when the operation-corresponding motor speed is equal to or lower than the minimum required speed, the minimum required speed is set instead of the operation-corresponding motor speed, and the electric motor is controlled to be driven at the set speed. On the other hand, when the operating device is operated in a combined manner to operate two or more of the plurality of hydraulic actuators in a combined manner, a total motor speed obtained by adding up the operation-corresponding motor speeds corresponding to the respective operation amounts of the combined operations is set, and when the total motor speed is equal to or lower than the minimum required speed, the minimum required speed is set instead of the total motor speed, and the electric motor is controlled to be driven at the set speed.

In the above-described operation control device, the required minimum rotation speed is preferably the minimum drive rotation speed required to drive the hydraulic pump.

In the actuation control device configured as above, preferably, the operation-responsive motor speed that is set when the operating device is operated independently is set for each of the multiple hydraulic actuators.

In the actuation control device configured as above, preferably, the operation-responsive motor speed that is set when the operating device is operated in a combined manner is set for each of the multiple hydraulic actuators.

In the actuation control device having the above configuration, preferably, when the operating device is operated in a composite manner to operate two or more of the plurality of hydraulic actuators in a composite manner, the total motor rotation speed is set to a value obtained by multiplying the sum of the operation-corresponding motor rotation speeds corresponding to the respective operation amounts of the composite operation by a predetermined coefficient K (K<1.0).

The actuation control device of the above configuration preferably includes a plurality of hydraulic oil supply control valves that are provided in the oil passages leading from the hydraulic supply source to the plurality of hydraulic actuators and that control the supply of hydraulic oil to corresponding one of the plurality of hydraulic actuators in response to selective or combined operation of the plurality of hydraulic actuators.

In the above-described operation control device, the hydraulic pump is preferably a fixed displacement hydraulic pump.

In the above-described operation control device, the hydraulic pump is preferably a variable displacement hydraulic pump.

According to the operation control device for a work vehicle of the present invention, when the operating device is operated in a combined manner, a total motor rotation speed is set by adding up the operation-corresponding motor rotation speeds corresponding to each operation amount of the combined operation, and when the total motor rotation speed is equal to or lower than the minimum required rotation speed, the minimum required rotation speed is set instead of the total motor rotation speed, and the electric motor is controlled to achieve the rotation speed thus set. Therefore, while driving the hydraulic pump at or above the minimum required rotation speed, when the operation amount is small in the combined operation, the motor drive rotation speed is kept to the minimum required, thereby reducing the power consumption of the electric motor.

1 is a perspective view of a hydraulic excavator equipped with an operation control device according to the present invention. 1 is a hydraulic circuit diagram showing an operation control device according to the present invention. FIG. 2 is a hydraulic circuit diagram illustrating a configuration in which a controller controls the operation of a boom cylinder and an arm cylinder in the above-mentioned operation control device. 5 is a flowchart showing a drive rotation control of a first electric motor in response to an operation of a boom and arm operating lever. 5 is a flowchart showing an individual operation control constituting the drive rotation control. 5 is a flowchart showing a composite operation control constituting the drive rotation control. 4 is a graph showing a setting relationship between a lever operation amount and a motor rotation speed. 11 is a graph showing the relationship between the lever operation amount and the motor drive rotation speed in a single operation. 11 is a graph showing the relationship between an operation amount and an actuation speed according to an actuation gain.

The following describes an embodiment of the present invention with reference to the drawings. In this embodiment, a crawler-type hydraulic excavator (excavator) will be described as an example of a work vehicle equipped with an operation control device according to the present invention. First, the overall configuration of the hydraulic excavator 1 will be described mainly with reference to FIG. 1.

As shown in FIG. 1, the hydraulic excavator 1 is configured to have a lower traveling body 10 that is configured to be able to travel, an upper rotating body 20 that is provided above the lower traveling body 10 and is capable of horizontal rotation, and a shovel unit 30 that is provided in front of the upper rotating body 20. The lower traveling body 10, the upper rotating body 20, and the shovel unit 30 are driven by hydraulic actuators.

The lower running body 10 is equipped with a pair of left and right crawler mechanisms 15, each of which has a drive wheel, a number of driven wheels, and a track 13 wrapped around these wheels, on the left and right sides of the running body frame 11. The left and right crawler mechanisms 15 have left and right running motors 16L, 16R (hydraulic actuators) that rotate the drive wheels. The lower running body 10 can run in any direction and at any speed by controlling the rotation direction and rotation speed of the left and right running motors 16L, 16R. A blade 18 is provided at the front of the running body frame 11 so that it can swing up and down. The blade 18 can swing up and down by extending and retracting a blade cylinder 19 (hydraulic actuator) that is straddled between the running body frame 11 and the blade 18.

A swivel mechanism is provided at the upper center of the traveling body frame 11. The swivel mechanism has an inner wheel fixed to the traveling body frame 11, an outer wheel fixed to the upper rotating body 20, a swivel motor 26 (hydraulic actuator, see FIG. 2) provided on the upper rotating body 20, and a swivel joint for supplying hydraulic oil from a hydraulic pump provided on the upper rotating body 20 to the left and right traveling motors 16L, 16R and the blade cylinder 19 provided on the lower traveling body 10. The upper rotating body 20 is attached to the traveling body frame 11 via the swivel mechanism so as to be horizontally rotatable, and can be rotated left and right relative to the lower traveling body 10 by operating the swivel motor 26 in the forward or reverse direction. A main body side bracket 22 protruding forward is provided at the front of the upper rotating body 20.

The excavator 30 is composed of a boom bracket 39 attached to the main body bracket 22 so as to be freely swingable in the left-right direction around a vertical axis, a boom 31 attached to the boom bracket 39 by a first swing pin 35a so as to be freely swingable up and down (free to rise and fall), an arm 32 attached to the tip of the boom 31 by a second swing pin 35b so as to be freely swingable up and down (free to bend and stretch), and a link mechanism 33 provided at the tip of the arm 32. The excavator 30 is further composed of a swing cylinder 34 (hydraulic actuator) straddling between the upper rotating body 20 and the boom bracket 39, a boom cylinder 36 (hydraulic actuator) straddling between the boom bracket 39 and the boom 31, an arm cylinder 37 (hydraulic actuator) straddling between the boom 31 and the arm 32, and a bucket cylinder 38 (hydraulic actuator) straddling between the arm 32 and the link mechanism 33.

The boom bracket 39 can swing left and right relative to the upper rotating body 20 (main body side bracket 22) by extending and retracting the swing cylinder 34. The boom 31 can swing up and down (can be raised and lowered) relative to the main body side bracket 22 (upper rotating body 20) by extending and retracting the boom cylinder 36. The arm 32 can swing up and down (can be bent and extended) relative to the boom 31 by extending and retracting the arm cylinder 37.

Various attachments serving as hydraulic actuators, such as a bucket, breaker, crusher, cutter, and auger device, can be attached to the ends of the arm 32 and link mechanism 33 so that they can swing up and down. The attachment attached to the end of the arm 32 can swing up and down relative to the arm 32 via the link mechanism 33 by expanding and contracting the bucket cylinder 38. First to third attachment connection ports 41 to 43, to which hydraulic hoses for supplying hydraulic oil to the hydraulic actuators of these attachments can be connected, are provided on both the left and right sides of the arm 32.

The upper rotating body 20 is composed of a rotating frame 21 having a main body side bracket 22 provided at the front, and an operator cabin 23 provided on the rotating frame 21. The operator cabin 23 is formed in a substantially rectangular box shape, forming an operation room inside in which an operator (worker) can ride, and is provided with a cabin door 24 that can be opened and closed sideways at the left side. Inside the operator cabin 23, there are provided an operator seat on which the operator sits facing forward, a display device that displays various vehicle information of the hydraulic excavator 1, and various operation switches that are operated by the operator. Also provided inside the operator cabin 23 are an operation device 160 (see FIG. 2) that is operated to operate the hydraulic actuator, and an operation gain setting indicator 170 (see FIG. 2) that is operated to set the operation speed gain of the hydraulic actuator. The operating device 160 has, as operating parts when operated by an operator, left and right travel operation levers or travel operation pedals (neither of which is shown in the figures) for operating the lower traveling body 10, left and right work operation levers 161, 162 (see Figure 2) for operating the upper rotating body 20 and the shovel device 30, and a blade operation lever (not shown in the figures) for operating the blade 18.

In the hydraulic excavator 1, an operator sits inside the operator cabin 23 and tilts the left and right travel control levers (or travel control pedals) forward and backward to drive the left and right crawler mechanisms 15 (travel motors 16L, 16R) according to the direction and amount of operation, thereby causing the hydraulic excavator 1 to travel.
By tilting 162 back and forth and left and right, the upper rotating body 20 and the shovel device 30 can be driven according to the direction and amount of operation to perform work such as excavation.

A horn device 28 is provided at the front of the revolving frame 21. By pressing a horn switch inside the operator cabin 23, the horn device 28 can emit a warning sound to alert people around the hydraulic excavator 1. At the rear of the revolving frame body 20, behind the operator cabin 23, there is provided a mounting compartment in which the main parts of the operation control device 100, which will be described later, are mounted. A curved counterweight 29 is provided to form the rear wall of this mounting compartment.

As shown in FIG. 2, the actuation control device 100 includes a hydraulic oil tank T, a first hydraulic pump P1 that discharges hydraulic oil for actuating the left and right travel motors 16L, 16R, etc., a swing hydraulic pump P2 that discharges hydraulic oil only for actuating the swing motor 26, a control valve unit 110 that controls the supply direction and flow rate of the hydraulic oil discharged from the first hydraulic pump P1 and supplied to the left and right travel motors 16L, 16R, etc., a swing control valve 121 that controls the supply direction of the hydraulic oil discharged from the swing hydraulic pump P2 and supplied to the swing motor 26, and a pilot pressure supply valve unit 130 that generates and supplies pilot pressure for controlling the actuation of the control valve unit 110 and the swing control valve 121, respectively.

The control valve unit 110 includes control valves that control the supply and discharge, supply direction, and flow rate of hydraulic oil supplied to the left and right travel motors 16L, 16R, the boom cylinder 36, the arm cylinder 37, the bucket cylinder 38, the swing cylinder 34, the blade cylinder 19, and the first to third attachment connection ports 41 to 43. These control valves include left and right travel control valves 111, 112, a boom control valve 113, an arm control valve 114, a bucket control valve 115, a swing control valve 116, a blade control valve 117, and an attachment control valve 118. Each of these control valves 111 to 118 has a built-in spool that is moved by the pilot pressure supplied from the pilot pressure supply valve unit 130, and the movement of the spool makes it possible to control the supply and discharge, supply direction, and flow rate of hydraulic oil supplied to each hydraulic actuator.

In the swing control valve 121, similar to the control valves 111 to 118, a built-in spool is moved by the pilot pressure supplied from the pilot pressure supply valve unit 130. In the swing control valve 121, the movement of the spool controls only the supply and discharge and supply direction of the hydraulic oil supplied to the swing motor 26. The flow rate control of the hydraulic oil supplied to the swing motor 26 (i.e., the swing speed control of the upper swing body 20) is performed by controlling the rotation of the second electric motor M2, which will be described later.

The pilot pressure supply valve unit 130 is provided in a branch oil passage L2 branched from a pump oil passage L1 that connects the discharge port of the first hydraulic pump P1 to the control valve unit 110. The branch oil passage L2 is provided with a check valve 135 for maintaining a hydraulic pressure required for the pilot pressure supply valve unit 130 to generate pilot pressure. The pilot pressure supply valve unit 130 generates pilot pressure according to the operation direction and operation amount of each of the travel operation lever (travel operation pedal), work operation levers 161, 162, and blade operation lever provided in the operator cabin 23, using the hydraulic oil discharged from the first hydraulic pump P1, and supplies the pilot pressure to the corresponding control valve. The pilot pressure supply valve unit 130 has a plurality of electromagnetic proportional pilot pressure supply valves (described in detail later) for supplying pilot pressure to the corresponding control valves.

The operation control device 100 further includes a first electric motor M1 that drives the first hydraulic pump P1, a second electric motor M2 that drives the swing hydraulic pump P2, a battery 105 (storage battery) that can be charged from an external power source or the like, an inverter 106 that converts DC power from the battery 105 into AC power and changes the frequency and voltage, a first pressure sensor S1 that detects the operating oil pressure (pump pressure) discharged from the first hydraulic pump P1, a controller 150 that performs various controls (described in detail below), the above-mentioned operating device 160, and an operation gain setting indicator 170.

The first and swing hydraulic pumps P1 and P2 are fixed displacement hydraulic pumps that discharge hydraulic oil at a flow rate that corresponds to the output of the first and second electric motors M1 and M2. Note that variable displacement hydraulic pumps may also be used as these pumps.

Next, the contents of control by the controller 150 will be described. As described above, the operator in the operator cabin 23 tilts the work operation levers 161, 162 constituting the operation device 160 forward, backward, left and right to drive the upper rotating body 20 and the shovel device 30 according to the operation direction and operation amount, thereby performing work such as excavation. In the following, an example of operation control when the boom operation lever 163 and the arm operation lever 164 are operated in the work operation levers 161, 162 will be described with reference to FIG. 3. Note that FIG. 3 is a hydraulic circuit diagram for explaining the control contents when the controller 150 controls the operation of the boom cylinder 36 and the arm cylinder 37. FIG. 3 shows only the components necessary for explaining the control contents, and only the boom operation lever 163 and the arm operation lever 164 are shown as the operation device 160.

In addition, FIG. 3 also shows an operating gain setting indicator 170. The operating gain setting indicator 170 has a gripping operation part 171 that can be rotated within a predetermined angle range while being held by an operator with his fingers, and is configured to output an operating gain instruction signal corresponding to the operation amount (rotation angle position) of the gripping operation part 171 to the controller 150. The operating gain signal is an instruction signal for causing the controller 150 to set an operating speed gain, which will be described later. The controller 150 can set the operating speed gain according to this operating speed gain signal.

The boom operation lever 163 and the arm operation lever 164 are joystick-type operation levers that output operation output signals corresponding to their operation to the controller 150. Specifically, when the boom operation lever 163 is operated, it outputs an operation output signal for operating the boom cylinder 36, and when the arm operation lever 164 is operated, it outputs an operation output signal for operating the arm cylinder 37. These operation levers 163, 164 are configured to output operation output signals with higher signal levels (e.g., voltage values or current values) in accordance with the amount of operation (operation stroke) as the amount of operation increases.

In this way, the operation output signal output in response to the operation of the boom and arm operation levers 163, 164 is sent to the controller 150, and the drive speed of the first electric motor M1 is controlled via the inverter 106. Furthermore, the operation of the boom control valve 113 and the arm control valve 114 is controlled via the pilot pressure supply valve unit 130, and the operation of the boom cylinder 36 and the arm cylinder 37 is controlled.

First, the drive rotation control of the first electric motor M1 in response to the operation of the boom and arm operation levers 163, 164 performed by the controller 150 will be described with reference to the flowcharts of Figures 4 to 6 and the graphs of Figures 7 and 8. In this drive rotation control, as shown in Figure 4, first, the operation output signal sent from the boom and arm operation levers 163, 164 in response to the lever operation is read (step S1), and it is determined whether the operation is a single operation in which only one lever is operated, or a combined operation in which multiple levers are operated simultaneously (step S2). If it is a single operation, the single operation control shown in Figure 5 is performed (step S10), and if it is a combined operation, the combined operation control shown in Figure 6 is performed (step S20).

In the case of a single operation, as shown in Fig. 5, first, the operation-corresponding rotational speed CMS is obtained (step S11). As shown in Fig. 7, the operation-corresponding rotational speed CMS is preset and stored in correspondence with the lever operation amount. The operation amount (%) is obtained from the operation output signal read in step 1, and the corresponding rotational speed corresponding to this operation amount is obtained from the relationship shown in Fig. 7. As shown in Fig. 7, the operation-corresponding rotational speed is set for each lever operation (for each hydraulic actuator to be operated by the lever operation). For example, when the arm 32 is operated in the excavation direction, the characteristic shown by the solid line in Fig. 7 is set, and when the boom 31 is operated in the lifting direction, the characteristic shown by the broken line in Fig. 7 is set. Therefore, when a single lever operation is performed to operate the arm 32 in the excavation direction, the arm excavation operation-corresponding rotational speed CMS(A) corresponding to this lever operation is obtained from the characteristic shown by the solid line in Fig. 7, and when a single lever operation is performed to operate the arm 32 in the boom lifting direction, the boom lifting operation-corresponding rotational speed CMS(B) corresponding to this lever operation is obtained from the characteristic shown by the broken line in Fig. 7.

Next, the process proceeds to step S12, where it is determined whether the operation-responsive rotation speed CMS (CMS(A) or CMS(B)) thus determined is less than the minimum required rotation speed (e.g., a value of about 500 to 700 rpm) required to drive the first hydraulic pump P1. If the operation-responsive rotation speed CMS is equal to or greater than the minimum required rotation speed, the process proceeds to step S13, where the operation-responsive rotation speed CMS thus determined is set as the motor drive rotation speed MDS. On the other hand, if the operation-responsive rotation speed CMS is less than the minimum required rotation speed, the process proceeds to step S14, where the minimum required rotation speed is set as the motor drive rotation speed MDS. Then, the first electric motor M1 is rotated at the motor drive rotation speed MDS thus set (step S15). The motor drive rotation speeds corresponding to the individual lever operation amounts thus obtained are shown in FIG. 8.

Next, the composite operation control (step S20) performed in the case of a composite operation will be described with reference to FIG. 6. In the case of a composite operation, first, the operation corresponding rotational speeds CMS (CMS(A), CMS(B)) corresponding to each lever operation are obtained (step S21). As described above, the operation corresponding rotational speeds CMS are set and stored in advance in correspondence with the lever operation amount as shown in FIG. 7, and the corresponding rotational speeds corresponding to the operation amount of each lever operation that constitutes the composite operation are obtained. Here, an example will be described in which a composite operation of a lever operation that operates the arm in the excavation direction and a lever operation that operates the arm in the boom raising direction is performed. In step S21, the arm excavation operation corresponding rotational speed CMS(A) corresponding to a single lever operation that operates the arm in the excavation direction and the boom raising operation corresponding rotational speed CMS(B) corresponding to a lever operation that operates the arm in the boom raising direction are obtained.

Then, the process proceeds to step S22, where the total rotation speed TMS (= CMS(A) + CMS(B)) is calculated. The process then proceeds to step S23, where the calculated total rotation speed TMS is multiplied by a correction coefficient K (< 1.0) to calculate a corrected total rotation speed MTMS. Note that the correction coefficient K is set to a value of approximately 0.5 to 0.9. This prevents the total rotation speed from becoming too large when the operation amount is large during combined operation, and exceeding the allowable rotation speed of the hydraulic pump. For this reason, the correction coefficient K is set appropriately according to various conditions, etc.

Next, the process proceeds to step S24, and the corrected total revolution speed MTMS thus obtained is compared with the first
It is determined whether the operation-responsive rotational speed CMS is less than the minimum required rotational speed (for example, a value of about 500 to 700 rpm) required for driving the hydraulic pump P1. If the operation-responsive rotational speed CMS is equal to or greater than the minimum required rotational speed, the process proceeds to step S25, where the determined corrected total rotational speed MTMS is set as the motor drive rotational speed MDS. On the other hand, if the corrected total rotational speed MTMS is less than the minimum required rotational speed, the process proceeds to step S26, where the minimum required rotational speed is set as the motor drive rotational speed MDS. Then, the first electric motor M1 is rotated at the motor drive rotational speed MDS thus set (step S27).

Next, the operation control of the boom cylinder 36 and the arm cylinder 37 performed by the controller 150 that receives the operation output signal output in response to the operation of the boom and arm operation levers 163, 164 will be described. The controller 150 that receives the operation output signal output in response to the operation of the boom and arm operation levers 163, 164 controls the operation of the boom control valve 113 and the arm control valve 114 via the pilot pressure supply valve unit 130, and the operation of the boom cylinder 36 and the arm cylinder 37 is controlled.

3, the movement position of a built-in spool is controlled by pilot pressure supplied from pilot pressure supply valves 131, 132 in a pilot pressure supply valve unit 130, thereby controlling the supply direction and flow rate of hydraulic oil supplied to the boom cylinder 36 and the arm cylinder 37. The pilot pressure supply valves 131, 132 are electromagnetic proportional pilot pressure control valves, and are operated by a pilot pressure control signal from a controller 150 to control the pilot pressure supplied to the boom control valve 113 and the arm control valve 114, thereby controlling the operation of these valves.

In this embodiment, the control is performed taking into account the actuation speed gain set by the actuation gain setting indicator 170. The actuation speed gain is set and adjusted by the controller 150 by rotating the grip operation part 171 of the actuation gain setting indicator 170 by the operator. The actuation speed gain is set as a parameter (e.g., a coefficient) that determines the correspondence between the operation amount of the operation lever in the operation device 160 and the actuation speed of the corresponding hydraulic actuator (the supply flow rate of hydraulic oil supplied to the hydraulic actuator). By changing the setting of this actuation speed gain according to the rotation angle position of the grip operation part 171, it is possible to adjust the supply flow rate (actuation speed) to the hydraulic actuator for the same operation amount, as shown in FIG. 9. In FIG. 9, the supply flow rate of the hydraulic actuator is set to change linearly (proportionally) with respect to the operation amount, but various characteristics can be set in consideration of various conditions. For example, it may be set so that it changes linearly in a region where the operation amount is small, but changes in a curved shape when the operation amount increases.

Although the embodiment of the present invention has been described above, the scope of the present invention is not limited to the above-mentioned embodiment. For example, in the above-mentioned embodiment, the opening degree of the control valves 111 to 118 is controlled by the pilot pressure supplied from the pilot pressure supply valve unit 130, but the control valves 111 to 118 may be configured as electromagnetic proportional control valves, and the opening degree of the control valves 111 to 118 may be electromagnetically controlled. In addition, the opening degree of the control valves 111 to 118 may be controlled using a drive device such as an electric motor. In the above-mentioned embodiment, the pilot pressure is generated using hydraulic oil from the first hydraulic pump P1, but a pilot hydraulic pump driven together with the first hydraulic pump P1 by the first electric motor M1 may be provided, and the pilot pressure may be generated using hydraulic oil from this pilot hydraulic pump.

The setting (initial setting) of the operating characteristics of the hydraulic actuator in response to the operation of the control lever may be configured to be changeable for each hydraulic actuator. For example, in order to change the setting of the correspondence relationship between the operation amount of the control lever and the operating speed (supplied oil amount) of the corresponding hydraulic actuator, the setting of the required discharge flow rate:operation amount ratio or the setting of the operating speed gain value may be changed. This setting change can be made, for example, via a portable computer (equipped with a program for changing settings) electrically connected to the controller 150.

When the upper rotating body 20 is rotated and the crawler mechanism 15 and the excavator device 30 are operated simultaneously, the discharge flow rate of the first hydraulic pump P1 may be controlled to be reduced by the discharge flow rate of the rotation hydraulic pump P2 (the horsepower of the first hydraulic pump P1 may be reduced by the horsepower of the rotation hydraulic pump P2). In addition, the above embodiment shows an example in which the present invention is applied to a hydraulic excavator, but the present invention can be similarly applied to work vehicles other than hydraulic excavators to obtain similar effects.

REFERENCE SIGNS LIST 1 Hydraulic excavator 10 Lower traveling body 16L, 16R Travel motor 20 Upper rotating body 26 Swing motor 30 Shovel device 36 Boom cylinder 37 Arm cylinder 38 Bucket cylinder 100 Operation control device 110 Control valve unit 130 Pilot pressure supply valve unit 150 Controller 160 Operation device 170 Operation gain setting indicator M1 First electric motor M2 Second electric motor P1 First hydraulic pump P2 Swing hydraulic pump

Claims (8)

In a work vehicle equipped with a hydraulic actuator,
An actuation control device comprising: a plurality of hydraulic actuators for driving the hydraulically actuated device; an operating device for selectively or in combination operating the plurality of hydraulic actuators to drive the hydraulically actuated device; a hydraulic oil supply source that delivers hydraulic oil for driving the plurality of hydraulic actuators; and an oil delivery control device that controls the amount of oil delivered from the hydraulic oil supply source,
The hydraulic oil supply source is composed of an electric motor and a hydraulic pump driven by the electric motor,
The oil discharge amount control device is configured to control the amount of oil discharged from the hydraulic pump by controlling the rotation of the electric motor in response to the operation of the operating device,
when the operating device is independently operated to selectively operate any one of the plurality of hydraulic actuators, an operation-responsive motor rotation speed is set according to an amount of operation of the operating device, and when the operation-responsive motor rotation speed is equal to or lower than a minimum required rotation speed, the minimum required rotation speed is set in place of the operation-responsive motor rotation speed, and drive control is performed on the electric motor so as to achieve the set rotation speed;
an operation control device for a work vehicle, characterized in that, when the operating device is subjected to a composite operation that activates two or more of the plurality of hydraulic actuators in a composite operation, a total motor rotation speed is set by adding up the operation-corresponding motor rotation speeds corresponding to each of the operation amounts of the composite operation, and when the total motor rotation speed is equal to or lower than the required minimum rotation speed, the required minimum rotation speed is set instead of the total motor rotation speed, and drive control of the electric motor is performed so as to achieve the set rotation speed. The operation control device for a work vehicle according to claim 1, characterized in that the required minimum rotational speed is the minimum driving rotational speed required when driving the hydraulic pump. The operation control device for a work vehicle according to claim 1 or 2, characterized in that the operation-responsive motor speed, which is set when the operating device is operated alone, is set for each of the multiple hydraulic actuators. An operation control device for a work vehicle according to any one of claims 1 to 3, characterized in that the operation-responsive motor speed that is set when the operating device is operated in a combined manner is set for each of the multiple hydraulic actuators. The operation control device for a work vehicle according to claim 1 or 2, characterized in that when the operating device is operated in a composite manner to operate two or more of the plurality of hydraulic actuators in a composite manner, the total motor rotation speed is set to a value obtained by multiplying the sum of the operation-corresponding motor rotation speeds corresponding to the respective operation amounts of the composite operation by a predetermined coefficient K (K<1.0). a hydraulic passage extending from the hydraulic supply source to the hydraulic actuators;
4. An operation control device for a work vehicle as described in any one of claims 1 to 3, further comprising a plurality of hydraulic oil supply control valves that control the supply of hydraulic oil to corresponding hydraulic actuators among the plurality of hydraulic actuators in response to selective or combined operation of the plurality of hydraulic actuators. The operation control device for a work vehicle according to claim 6, characterized in that the hydraulic pump is a fixed displacement hydraulic pump. 7. The operation control device for a work vehicle according to claim 6, wherein the hydraulic pump is a variable displacement hydraulic pump.

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