JP2001020325A - Actuator drive controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a high responsiveness over a whole operation region of an operation lever without causing erroneous operation in an actuator drive controller. SOLUTION: In a controller 20, a lever angle θ1, a lever speed ω, and a lever acceleration dω/dt of an operation lever 10a are calculated from pulse signals of a potentiometer 11, and a command current value (i) corresponding to the lever angle θ1 is calculated. Moreover, a distance (angle) L at which the operation lever 10a moves in Δt seconds is estimated based on the lever speed and the acceleration. When this distance L exceeds a threshold value determined in advance, the controller 20 judges that an overcurrent should be applied, calculates an overcurrent value (magnitude, direction, and time of overcurrent) based on a current value for generating a pilot pressure equivalent to a lever position after Δt seconds (current position + the estimated travel distance), adds the value to the command current value (i), and outputs the obtained value to an electromagnetic proportional control valve 30a or 30b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuator drive control device, and more particularly to an actuator drive control device for controlling an actuator by operating a spool type directional control valve using an electromagnetic proportional control valve by operating an electric operation lever device. About.

[0002]

2. Description of the Related Art Japanese Patent No. 2695335 discloses an actuator drive control device that controls an actuator by operating a spool type directional control valve using an electromagnetic proportional control valve by operating an electric operation lever device. Have been. This prior art includes a hydraulic actuator control device provided with a flow control means A for proportionally controlling the opening of an electromagnetic proportional flow control valve by supplying a current according to the operation amount of an operation lever. At the start of the driving operation from the position, a current control means B for supplying a one-shot current larger than the target current in the flow control means corresponding to the operation amount of the operation lever to the electromagnetic proportional flow control valve for a predetermined time is provided. I have.

As a method of supplying a one-shot current larger than the target current, (2) means for detecting the operating speed of the operating lever is provided. A current value changing means C for changing the current value of the one-shot current by the current control means B so as to increase the supply current value to the proportional flow control valve is provided, and (3) the operating oil pressure of the hydraulic actuator is detected. A pressure sensor is further provided, and a one-shot current is supplied by the current control means B until the pressure detected by the pressure sensor reaches a predetermined value. (4) The operation of (2) above is performed only when the operation lever is in a low speed range. The speed is detected, and the current value of the one-shot current by the current control means B is changed based on the detection result.

According to the description of Japanese Patent No. 2695335, the following effects can be obtained by the above configuration.

By supplying a one-shot current larger than the target current for a predetermined time at the start of operation as described in (1) above, the spool is activated strongly even if the start-up response of the electromagnetic proportional flow control valve is slow, Advance the start timing,
The subsequent movement can be controlled smoothly.

By changing the current value of the one-shot current of (1) according to the operating speed of the operating lever as in (2) above, the response delay is corrected only when the operating lever is moved quickly, and When the lever is moved slowly, the response does not become faster than the operator's intention.

By supplying the one-shot current until the pressure of the actuator reaches a predetermined value as in the above (3), the inconvenience of monitoring the working state of the actuator and performing unnecessary overdrive can be avoided.

The control of (2) is performed only when the operating lever is in the low speed range as in (4) above, so that the operating lever is on the high-speed drive side (when the operating lever is largely moved) or at low speed. If the operation is slow even on the side, the supply of the one-shot current is not performed, and the occurrence of a drive shock can be prevented.

[0009]

However, the above prior art has the following problems.

First, in the prior art, the above-mentioned (1) is used as a base, and the above-mentioned processes (2) to (4) are added thereto. However, in such a method, when the operation of the operation lever is started from the neutral position, the speed can be increased by supplying a one-shot current larger than the target current, but the operation lever can be rapidly operated from a position other than the neutral position. When moved, a large current does not flow and response cannot be improved. For example, when the operating lever is suddenly returned from the high speed range, a large current does not flow, and the dead time increases. In addition, this method is limited to the acceleration side, and the response in the operation of the operation lever on the deceleration side and the operation on the opposite side is still slow. For this reason, it is not possible to appropriately cope with work requiring a high speed even on the deceleration side of the operation lever, such as mud dropping of the front bucket or trajectory control of the front.

Although the current value of the one-shot current is changed according to the operation speed of the operation lever as described in (2) above, the magnitude of the operation speed alone indicates how far the operator wants to move the operation lever. There is a lack of such information, and determining the one-shot current value based on this value alone may not always meet the operator's intention. For example, if the acceleration is large even at the same speed, the operator wants to move the operation lever largely. In this case, a large current value may flow, but if the acceleration is small or negative, the operator Is to end the operation, so that the smaller the current value is, the better. Therefore, since only the lever speed is used as a parameter, there arises a problem that the lever moves excessively or is slower than expected.

Further, when the pressure of the actuator is fed back as in (3) above, the actuator of the earth moving machine generates pressure even if it is not operated by the attitude of the front, so that the predetermined pressure is set to a low pressure. It is difficult. When the predetermined pressure is set to be high, the actuator becomes vibratory, becomes faster than the operator intends, and may malfunction.

An object of the present invention is to provide an actuator drive control device capable of achieving high response without malfunctioning over the entire operation range of the operation lever.

[0014]

(1) In order to achieve the above object, the present invention provides an electric operation lever device for outputting an electric signal corresponding to the lever position of an operation lever, and an input of the electric signal. Control arithmetic means for outputting a current command value;
An actuator drive control device comprising: an electromagnetic proportional control valve that generates a pressure proportional to a current command value of the control operation means; and a spool-type directional control valve that operates by the pressure generated by the electromagnetic proportional control valve and controls an actuator. Means for detecting a lever position of the operation lever;
Means for calculating the speed and acceleration of the operating lever based on the lever position; and command value changing means for predicting the movement of the operating lever based on the speed and acceleration of the operating lever and making the current command value variable. Shall be.

Thus, the lever position detecting means, the lever speed / acceleration calculating means, and the command value varying means are provided to predict the movement of the operating lever based on the speed and acceleration of the operating lever to vary the current command value. Accordingly, the operation becomes effective when the operation lever is moved in any direction from any position other than the neutral position of the operation lever, and the actuator can be driven with high response over the entire operation range of the operation lever.

For example, a negative overcurrent is calculated not only when the operating lever changes from neutral, but also when the operating lever returns to the neutral side, which not only improves the rising response from the neutral state of the operating lever, but also It shows as sensitive a reaction as necessary even during operation or falling. For this reason, it is possible to cope with a high frequency response by manual operation, and it can be applied to, for example, a repetitive operation such as a bucket dropping and a pile-out.

Further, since the movement of the operation lever is predicted based on the speed and acceleration of the operation lever, the possibility of a malfunction such as the case of feeding back the pressure of the actuator is reduced. Furthermore, when the operator's hand accidentally touches the operation lever or when a minute operation is required, especially a bucket having a small mass may move contrary to the operator's intention, but these malfunctions may occur. Can be prevented.

(2) In the above (1), preferably,
The command value varying means predicts a distance that the operation lever moves based on the speed and acceleration of the operation lever, and calculates an overcurrent value that makes the current command value variable based on the predicted movement distance.

By calculating the overcurrent value based on the predicted moving distance of the operating lever, the command current value can be varied reflecting the intention of the operator. Can be supplied to the electromagnetic proportional control valve.

(3) In the above (2), preferably,
The command value changing means calculates a current value for generating a pilot pressure corresponding to a lever position at the time when the operation lever moves the predicted distance, and calculates the overcurrent value as a value corresponding to the current value. Is calculated.

As a result, it is possible to calculate an overcurrent value that allows the command current value to be varied reflecting the intention of the operator.

(4) In the above (3), preferably,
The command value varying means calculates a work amount of the current value required for a delay time of the rise of the pilot pressure when the current value is applied in a step-like manner, and calculates a maximum current amount of the work amount equal to the work amount. Calculate the application time and use it as the overcurrent value.

As a result, an overcurrent value for eliminating the response delay can be determined.

(5) In the above (1), preferably, the command value changing means predicts a distance that the operating lever moves based on the speed and acceleration of the operating lever, and the predicted moving distance is a predetermined value. If it exceeds, the current command value is made variable.

As described above, by making the current command value variable when the predicted movement distance of the operating lever exceeds a predetermined value, the command current value reflecting the intention of the operator can be changed, and the high response of the actuator can be achieved. The variable current can be supplied to the electromagnetic proportional control valve at the optimal timing for the conversion.

(6) In the above (1), when the speed of the operation lever exceeds a predetermined value, the command value changing means may output the command value.
The current command value may be made variable by a combination of a speed and an acceleration of the operation lever.

Thus, the operation described in the above (1) can be realized by the simplest method. The determination whether to make the current command value variable may be made based on whether the lever acceleration has exceeded a predetermined value instead of the lever speed.

(7) In the above (6), preferably,
When making the current command value variable, the command value variable means outputs a current value in a range where the actuator does not move as an overcurrent value that makes the current command value variable.

As a result, the current command value can be varied by a simple method as described in (6), and the actuator can be driven without causing a shock.

(8) Further, in the above (6), preferably, the command value varying means determines whether or not a series of operations of the operation lever is completed, and The command current value is made variable only once.

Thus, when determining whether to make the command current value variable at the speed of the operation lever as in (6) above, the command current value becomes continuously variable in a series of operations for operating the operation lever. This can be avoided, and once the command current value is made variable, it can be moved in the same manner as a normal operation system.

(9) In the above (8), preferably,
The command value changing means determines that a series of operations has been completed when the lever speed is equal to or less than a predetermined value.

This makes it possible to determine whether or not a series of operations of the operation lever has been completed.

[0034]

Embodiments of the present invention will be described below with reference to the drawings.

First, a first embodiment of the present invention will be described with reference to FIGS. In the first embodiment, an overcurrent is applied at any time according to the movement of the operation lever.

FIG. 1 is a system diagram showing the entire actuator drive control device of the present embodiment. In FIG. 1, reference numeral 10 denotes an electric operation lever device having an operation lever 10a.
A position detector for detecting the position of 0a, for example, a potentiometer 11 of a variable resistor is built in, and converts the displacement of the operation lever 10a into an electric signal. The position detector may be another displacement sensor, for example, a rotary encoder. Operation lever 1 detected by potentiometer 11 of variable resistor
The position signal of 0a is input to the controller 20. In the controller 20, the position detector 1 of the operation lever device 10 is used.
1, a position calculator 21 for calculating the position of the operation lever 10a from the position signal, and calculating the position of the operation lever 10a from the calculated value of the position.
Speed / acceleration calculator 2 for calculating the speed / acceleration signal of the vehicle
2. It is composed of an output control operation unit 23 that determines a command current value based on these signals. The command current value from the output control calculation unit 23 is output to the electromagnetic proportional control valves 30a and 30b, and the electromagnetic proportional control valves 30a and 30b generate a pressure (pilot pressure) proportional to the command current. This pressure is sent to a spool-type directional control valve 31, and the directional control valve 31
Is controlled, the flow of the pressure oil supplied from the hydraulic pump 32 to the actuator 33 is controlled, and the drive of the actuator 33 is controlled.

FIG. 2 schematically shows the processing functions of the controller 20.
Is shown in the block diagram.

Potentiometer 1 of operating lever device 10
1 is a pulse signal, and the position calculation unit 21 receives the pulse signal and calculates the angle (lever angle or lever position) of the operation lever 10a from the pulse signal.

The speed / acceleration calculator 22 is a speed calculator 22.
1, having an acceleration calculator 222 and an overcurrent calculator 225,
The speed calculation unit 221 converts the lever angle calculated by the position calculation unit 21 into an operation speed (lever speed) of the operation lever 10a, and the acceleration calculation unit 222 further converts the lever speed into an operation acceleration (lever acceleration) of the operation lever 10a. To
The overcurrent calculation unit 225 calculates an overcurrent value (the magnitude of the overcurrent, the direction in which the overcurrent flows, and the time) from the lever speed and the acceleration.

The output control calculation unit 23 converts the lever angle calculated by the position calculation unit 21 into a command current value by using a conversion table between the lever angle and the command current value which is set and stored in advance. Overcurrent calculation unit 22
The overcurrent value calculated in 5 is added, and the added current value is output to the electromagnetic proportional control valve 30a or 30b as a command current value.

FIG. 3 shows details of the processing function of the controller 20.
And the flowchart shown in FIG. FIG.
In the flowchart of FIG. 5, the portions corresponding to the operation units in the block diagram of FIG. 2 are denoted by the reference numerals of the operation units in parentheses.

In FIG. 3, when the program starts (step A), the lever angle θ1 of the operating lever 10a is calculated from the pulse signal of the potentiometer 11 (step B), and then the lever speed ω and the lever speed are calculated using the lever angle θ1. The acceleration dω / dt is calculated (steps C and D). At the same time, the lever angle θ set and stored in advance
A command current value i corresponding to the lever angle θ1 is calculated using a conversion table between 1 and the command current value i (step G).

Next, the lever speed ω and the lever acceleration dω
It is determined whether or not an overcurrent should be applied using / dt (step E1). If it is determined that an overcurrent should not be applied, the command current value i corresponding to the lever angle θ1 obtained in step G is determined. An output current is determined (step H), and this is output to the electromagnetic proportional control valve 30a or 30b.

If it is determined in step E1 that an overcurrent should flow, an overcurrent value (magnitude, direction, and time of the overcurrent) is calculated (step G1). The value is added to the value i (step H), and this is output to the electromagnetic proportional control valve 30a or 30b.

FIG. 4 shows a detailed flow of steps E1 and G1.
Shown in

In the present embodiment, the determination of whether or not an overcurrent should be applied in step E1 predicts the distance (angle) L by which the operation lever 10a moves by Δt seconds, and this distance L is predetermined. The overcurrent value is calculated based on whether the threshold value is exceeded, and the overcurrent value is calculated in step G1 by calculating a current value for generating a pilot pressure corresponding to the lever position (current position + the predicted movement distance) after Δt seconds. The calculation is performed by calculating the application time of the maximum current based on the current value.

First, the lever speed ω and the lever acceleration dω
Using / dt, a predicted value (predicted moving distance) of the moving distance (angle) of the operation lever 10a until after Δt seconds by the following equation:
Lt is calculated (step E11).

Lt = ωΔt + ／ ω′Δt ² (1) (“′” represents differentiation) Here, Δt may be set to an arbitrary time. In the present embodiment, as an example, the time until the pressure rises when the command current value i obtained in step G is input as a step signal is set as Δt (corresponding to t0 in FIG. 5B described later). I have. Other than this, the system dead time (corresponding to tL in FIG. 5B described later) or the operation lever 10
The time may be set at the time of the operation frequency in the manual operation of a (for example, 200 msec in the case of an operation frequency of 5 Hz).

Next, it is determined whether or not the predicted moving distance Lt has exceeded the set value Ls (step E12).
If it exceeds, an overcurrent is applied.

The concept of calculating the value of the overcurrent will be described.

First, in calculating the value of the overcurrent, Δ
The lever position L0 after t seconds is estimated. Since the lever position after Δt seconds can be estimated to be the sum of the current position θ and the predicted movement distance Lt, L0 = Lt + θ1 (2).

Here, assuming that the relationship between the lever position of the operation lever 10a and the pilot pressure to be generated by the electromagnetic proportional control valve 30a or 30b is as shown in FIG. 5 (a), the lever position after Δt seconds becomes When L0 is obtained, the pilot pressure to be generated by the electromagnetic proportional control valve 30a or 30b at that position is statically P0. It is also assumed that the electromagnetic proportional control valve 30a or 30b needs the current i0 statically to generate the pilot pressure of P0. In this case, as shown in FIG. 5B, even when the current i0 is applied in a stepwise manner, the pilot pressure rises with a delay of the time tL, and follows the target pressure P0 after the time t0.
The work amount of the current flowing to the electromagnetic proportional control valve 30a or 30b during this time is, as shown in FIG. 5C, Wout = i0 × t0 (3). The first idea is that this work is transferred to the electromagnetic proportional control valve 3.
That is, the current is supplied for a short time so that the same work amount is obtained at the maximum current imax that can be applied to 0a or 30b. Since the maximum current imax that can be applied is determined by the electromagnetic proportional control valve, the output time is as follows: tout = i0 × t0 / imax (4)

As a second idea, FIG.
This is to minimize only the dead time tL shown in FIG. In this case, the amount of work for covering the dead time tL is WLout = i0 × tL (5), and the output time tout of the maximum current imax is: tout = i0 × tL / imax (6) Become.

In the flowchart shown in FIG. 4, as an example, the value of the overcurrent is calculated based on the first concept of the equations (3) and (4).

First, the lever position after Δt seconds is determined by the above (2).
It is calculated by an equation (step G11). Next, a pilot pressure P0 corresponding to the estimated lever position L0 is calculated (step G12), a current i0 required to generate the pilot pressure P0 is obtained (step G13), and the current i0 is applied in a step shape. In this case, the time t0 until the pilot pressure P0 is obtained is calculated, and the work amount Wout during that time is calculated from the above equation (3) (step G1).
4) The application time tout for obtaining the work amount Wout at the maximum current imax is calculated from the above equation (4) (step G15).

After this processing, in the next processing cycle, the position, speed and acceleration of the operating lever 10a are calculated again (steps B, C and D), and the predicted value Lt of the moving distance of the operating lever 10a after Δt seconds is calculated. The calculation is performed (step E11). When Lt exceeds the set value Ls (step E12), the value of the overcurrent to be applied is calculated in the same manner as the previous time (step G1).
1). However, this case corresponds to the case where the operation lever 10a goes too far from the position calculated last time, and is performed by obtaining the position deviation ΔL as follows.

Assuming that the predicted movement distance of the operation lever 10a calculated last time is Lt0, the previous predicted lever position is θ0, the predicted movement distance of the operation lever 10a calculated this time is Lt, and the current predicted lever position is θ1. Because an overcurrent is flowing by predicting the distance the operation lever 10a moves,
In this case, the overcurrent is subtracted. The position deviation ΔL of the operation lever 10a on which the overcurrent is calculated is as follows: ΔL = (Lt + θ1) − (Lt0 + θ0) Then, a pilot pressure P0 corresponding to the position deviation ΔL is calculated (step G12), and a current value i0 for generating the pilot pressure P0 is calculated as described above.
Application time t of the maximum current imax based on the work amount Wout of
Out is calculated (steps G13 to G15).

By calculating the overcurrent value (the magnitude of the overcurrent and the direction and time of the overcurrent) as described above, an appropriate overcurrent value is calculated regardless of the direction in which the operation lever 10a is moved. In addition, appropriate high response can be achieved over the entire operation range of the operation lever.

For example, when returning the operation lever 10a from the full operation position to the neutral position, the speed and acceleration become negative, and the overcurrent value becomes negative.
By adding to the command current value i obtained in step (1), the command current value flowing to the electromagnetic proportional control valve 30a or 30b becomes 0, and the command current value can be reduced stepwise according to the speed and acceleration. In addition, when the energization time of the negative overcurrent value is long, the current may be applied to the electromagnetic proportional control valve 30b or 30a on the opposite side, and in this case, quicker return can be realized.

According to the above method, the operation lever 1
Even when the speed of the movement of 0a is low, the displacement of the operation lever 10a is predicted from the acceleration, so that the overcurrent can be applied earlier. In addition, even when the operation of the operation lever 10a is to be stopped, the signal can be returned to the normal driving method earlier. Can be prevented, and stable high-speed operation can be achieved.
Further, by flowing the applied current at the maximum current for the optimum time, an extremely high-speed operation can be performed as compared with the method of flowing a large current while feeding back the lever position and speed. In addition, it is possible to cope with an operation requiring a high frequency response, such as bucket dropping.

FIG. 6 shows an operation example.

In FIG. 6, (a) to (e) show the lever position (θ), the lever speed (ω), the lever acceleration (dω / dt), and the applied current ( i) shows changes in pilot pressure (P). FIG.
In the first half of the time axis of (a) to (e), when the operation lever 10a in the above embodiment is moved from neutral, FIGS.
In the latter half of the time axis of (e), when the operating lever 10a is moved from neutral and then returned to neutral, the two-dot chain line shown in the latter half of the time axis of FIGS. This is a case in which the operation lever 10a is moved further from the neutral position and temporarily stopped, and then the operation lever 10a is further moved. In FIGS. 6D and 6E, the broken lines indicate changes when the processing of the present invention is not performed.

When the operating lever 10a is moved from the neutral position, the lever speed increases. At time tA, the predicted moving distance Lt obtained from the speed (ω) and the acceleration (dω / dt) becomes equal to the threshold value (set value Ls). Is exceeded, the value of the overcurrent is calculated as described above, and the maximum current imax is applied as shown in FIG. At this time, the electromagnetic proportional control valve 30a or 30
The pilot pressure P at which b occurs is as shown in FIG. 6E, and the pilot pressure P increases at a high speed. Overcurrent is not applied from the point when the acceleration becomes negative, and the pilot pressure P
Vibration is minimized.

When the operation lever 10a is returned to the neutral position,
When the lever speed decreases and the predicted distance Lt calculated from the speed (ω) and the acceleration (dω / dt) exceeds the threshold value (set value Ls) at time tB, as shown in FIG. Is calculated, the current value 0 is applied, and the pilot pressure P becomes as shown in FIG.
Decreases at high speed.

When the operation lever 10a is further moved halfway, the value of the overcurrent is calculated as described above.
As shown in FIG. 6D, the maximum current imax is applied, and the pilot pressure P generated by the electromagnetic proportional control valve 30a or 30b increases at a high speed as shown in FIG.

As described above, according to the present embodiment, high responsiveness is realized without malfunctioning over the entire operation range of the operation lever, the operability of the electric operation lever device is greatly improved, and the fineness of the front is reduced. A wide range of work, such as operation, pile removal, bucket mud removal, etc., can be reliably handled.

In the present embodiment, the threshold value at which the overcurrent flows is a case where the predicted moving distance Lt exceeds the set value Ls. However, as will be described later, the lever speed or the acceleration is constant. If the value is exceeded, an overcurrent may be applied.

A second embodiment of the present invention will be described with reference to FIGS. In the present embodiment, by applying a constant overcurrent when the speed of the operation lever exceeds a set value, a method of determining the application of the overcurrent and a method of calculating the value of the load current are simplified.

The system configuration of this embodiment is the same as that of the first embodiment shown in FIG.

The processing function of the controller 20 is the same as that of the first embodiment except that the method of determining the application of overcurrent and the method of calculating the value of the load current are different from those of the first embodiment.

FIG. 7 is a diagram for explaining the concept of the method for determining the application of overcurrent and the method for calculating the value of the load current in this embodiment. FIG. 8 is a flowchart showing a main part of a processing procedure in the controller 20 (see FIG. 1) based on the concept. The overall processing procedure of this embodiment is the same as that shown in the flowchart of FIG. 3, and steps E1 and G1 in the flowchart of FIG.
Replaced with 2.

In this embodiment, the determination of the application of the overcurrent is made only by the lever speed of the operation lever 10a (see FIG. 1). That is, as shown in FIG. 7A, when the absolute value of the lever speed ω becomes equal to or more than the set value, that is, the threshold value ωs, it is determined that an overcurrent should be applied (step E in FIG. 8).
2), the value of the overcurrent is determined by the processing shown in FIG. 7B (step G2 in FIG. 8). Note that the determination of overcurrent application may be the same as in the first embodiment.

In step G2 of FIGS. 7B and 8, "+" and "-" of the lever speed ω and the acceleration dω / dt are defined as follows.

Lever speed ω: "+" (corresponding to (+) in FIG. 6B) when moving the operating lever 10a away from neutral, and "-" (corresponding to (+) in FIG. 6B).
(Corresponds to (-) in (b)) Lever acceleration dω / dt: “+” indicates acceleration when the lever speed is on the “+” side and deceleration when the lever speed is on the “−” side (FIG. 6).
(C) corresponds to (+)), when the lever speed decelerates on the “+” side, and when the lever speed accelerates on the “−” side, “−” (FIG. 6)
(Corresponding to (-) in (c)) When the operating lever is operated from neutral, the lever speed increases ("+" side) and the acceleration at that time also increases ("+" side). Since the operator is about to operate the operation lever, the electromagnetic proportional control valve 3
It is necessary to supply an overcurrent to 0a or 30b (see FIG. 1) to drive at high speed. Therefore, the overcurrent is set to a fixed value Δi of “+” (steps G21 → G22 → G24 in FIG. 8),
This is added to the output current corresponding to the lever position.
At this time, the magnitude of the overcurrent Δi is set to such a size that the actuator does not move even when Δi is output in a single shot in order to prevent a shock at the time of starting the actuator due to the overcurrent. Specifically, the magnitude of the overcurrent Δi is the same as the maximum current imax as in the first embodiment, and the maximum current i
The time Δt for flowing max is set to such a time that the actuator does not move.

When the absolute value of the lever speed ω exceeds the threshold value ωs and the acceleration is on the “−” side, it is a case where the operator is about to end the operation. Use a small value. In the present embodiment, the overcurrent is set to 0 (step G21 → G22 → G25 in FIG. 8) in order to prevent vibration and excessive movement.

Next, when the lever speed is "-" and the acceleration is "+", the operation lever 10a is returned to the neutral side, which corresponds to the case where the operator is about to end the operation. Therefore, the overcurrent again takes a value of 0 (steps G21 → G23 → G27 in FIG. 8).

Next, when the lever speed is "-" and the acceleration is also "-", since the operator is suddenly returning the lever, the overcurrent Δi is set to a constant value of "-" (FIG. 8). Step G21 → G23 → G26), and this is added to the output current corresponding to the lever position. Also in this case, the magnitude of the absolute value of the overcurrent Δi is the maximum current imax, and the time Δt at which the maximum current imax flows is set to a time that does not move the actuator.

If the absolute value of the lever speed ω is not equal to or greater than the threshold value ωs, only the current corresponding to the normal lever position is output (steps B → G → H → I in FIG. 3).

According to the present embodiment, the same effects as in the first embodiment can be obtained by a simpler method than in the first embodiment.

In this embodiment, the threshold is set to the speed, but the same can be applied to the case where the threshold is set to the acceleration.

FIGS. 9 and 10 show a third embodiment of the present invention.
This will be described below. This embodiment is different from the second embodiment shown in FIGS. 7 and 8 in that the application of the overcurrent is performed only once by operating a series of operation levers. This is different from the embodiment.

FIG. 9 is a diagram for explaining the concept of a method for determining the application of overcurrent in the present embodiment. FIG. 10 is a flowchart showing a main part of a processing procedure in the controller 20 (see FIG. 1) based on the concept. The overall processing procedure of this embodiment is the same as that shown in the flowchart of FIG. 3, and steps E1 and G in the flowchart of FIG.
1 is replaced by steps E3 and G2 in FIG.
Step G2 is the same as that of the second embodiment shown in FIG.

In FIG. 9, four types of operation patterns of the operation lever LA, LB, LC, and LD are considered. The end determination of the series of operations of the operation lever 10a is performed at the lever speed, and when the lever speed becomes close to 0, it is determined that the series of operations is completed. In the figure, the Δ marks of c1 and d1 indicate that point. LA and LB are a series of operations, and LC and LD are 2
Operation. In order to generate one overcurrent in a series of operations, the overcurrent flows at the point where the lever speed exceeds the threshold value, and the next overcurrent occurs until the lever speed approaches 0 and the series of operations ends. Do not shed. As a result, the actuator does not sensitively react to the fluctuation of the lever position when the operation lever is operated, and a response with a very small dead time can be realized.

In FIG. 10, first, it is determined whether the lever operation has been completed as described above by checking whether or not the lever speed ω is greater than a predetermined value ω0 (0) (step E31). . Lever speed ω is a predetermined value ω0
If it is smaller, a new series of operations starts from here, and the overcurrent flag is turned on (step E32). Next, it is determined whether or not the absolute value of the lever speed ω is equal to or more than the threshold value ωs (step E33), and the threshold value ωs
If so, the overcurrent flag is determined (step E3).
4). Here, only when the overcurrent flag is ON, the value of the overcurrent is calculated (step G2), and the overcurrent is applied (steps H and I in FIG. 3). Further, the overcurrent flag is turned off before calculating the value of the overcurrent (step E35).
Thus, in the next processing cycle, the overcurrent flag is set to OF.
F is determined (step E34), and only the current corresponding to the lever position is applied until this operation is completed (steps G, H and I in FIG. 3).

According to this embodiment, when determining whether or not to apply an overcurrent at the speed of the operating lever, it is possible to avoid determining that the overcurrent is applied continuously in a series of operations of operating the operating lever. After the overcurrent is applied once, it can be moved in the same manner as a normal operation system.

[0086]

According to the present invention, high responsiveness is realized without malfunctioning over the entire operation range of the operation lever, the operability of the electric operation lever device is greatly improved, and the fine operation of the front can be performed. It is possible to reliably cope with a wide range of work such as removing pile mud and bucket mud.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of an actuator drive control device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing processing functions of a controller shown in FIG.

FIG. 3 is a flowchart showing details of processing functions of a controller shown in FIG. 1;

FIG. 4 is a flowchart showing details of a main part of the processing function shown in FIG. 3;

5A is a diagram showing a relationship between an operation lever lever position and a pilot pressure to be generated by an electromagnetic proportional control valve, and FIG. 5B is a diagram when a current is applied to the electromagnetic proportional control valve in a stepwise manner; It is a figure which shows the rise of pilot pressure, and (c) is a figure which shows the amount of work of the electric current which flowed to the electromagnetic proportional control valve until the pilot pressure follows the target pressure.

FIG. 6 shows a lever position (θ) in the first embodiment,
It is a figure which shows the change of lever speed ((omega)), lever acceleration (d (omega) / dt), applied current (i), and pilot pressure (P) corresponding to this change of a lever position ((theta)).

FIG. 7 is a diagram for explaining the concept of a method of determining overcurrent application and a method of calculating a value of a charged current according to a second embodiment of the present invention.

FIG. 8 is a flowchart illustrating a main part of a processing procedure in a controller according to the second embodiment.

FIG. 9 is a diagram for explaining the concept of the overcurrent application determination process according to the third embodiment of the present invention.

FIG. 10 is a flowchart illustrating a main part of a processing procedure in a controller according to the third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Electric operation lever device 10a Operation lever 11 Potentiometer 20 Controller 21 Position operation part 22 Speed and acceleration operation part 221 Speed operation part 222 Acceleration operation part 225 Overcurrent operation part 23 Output control operation part 30a, 30b Electromagnetic proportional control valve 31 Spool type directional control valve 32 Hydraulic pump 33 Actuator

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Hiroshi Ogura 650, Kandate-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. Tsuchiura Plant (72) Inventor Kazuo Fujishima 650, Kandate-cho, Tsuchiura-shi, Ibaraki Hitachi, Ltd. Inside the Tsuchiura Plant of Shikiura Company (72) Inventor Tomita Tadashihisa 650, Kandamachi, Tsuchiura City, Ibaraki Prefecture Hitachi Construction Machinery Co., Ltd. (72) Inventor Masakazu Haga 650, Kandamachi, Tsuchiura City, Ibaraki Prefecture Hitachi Construction Machinery F-term in Tsuchiura Plant (reference) 2D003 BA01 CA02 DA03 DA04 DB04 DB05 EA00 3H089 CC01 DA02 DB75 EE31 EE36 FF07 GG02

Claims (9)

[Claims] 1. An electric operation lever device for outputting an electric signal according to a lever position of an operation lever, a control operation means for inputting the electric signal and outputting a current command value, and a current command for the control operation means. An actuator drive control device comprising: an electromagnetic proportional control valve that generates a pressure proportional to a value; and a spool type directional control valve that operates by the pressure generated by the electromagnetic proportional control valve and controls an actuator. Means for calculating the speed and acceleration of the operating lever based on the lever position; and a command for predicting the movement of the operating lever based on the speed and acceleration of the operating lever and making the current command value variable. An actuator drive control device comprising: a value changing unit. 2. The actuator drive control device according to claim 1, wherein the command value varying means predicts a distance of movement of the operation lever based on a speed and acceleration of the operation lever, and based on the predicted movement distance, the current value. An actuator drive control device for calculating an overcurrent value that makes a command value variable. 3. The actuator drive control device according to claim 2, wherein the command value changing means is configured to generate a current value for generating a pilot pressure corresponding to a lever position at the time when the operation lever moves the predicted distance. And calculating the overcurrent value as a value corresponding to the current value. 4. The actuator drive control device according to claim 3, wherein the command value varying means is configured to work the current value required for a delay time of the rise of the pilot pressure when the current value is applied stepwise. An actuator drive control device characterized in that the overcurrent value is calculated, and the overcurrent value is calculated by calculating the application time of the maximum current having the same work amount as the work amount. 5. The actuator drive control device according to claim 1, wherein the command value varying means predicts a distance that the operation lever moves based on a speed and an acceleration of the operation lever, and the predicted movement distance exceeds a predetermined value. And an actuator drive control device, wherein the current command value is made variable. 6. The actuator drive control device according to claim 1, wherein the command value changing means changes the current command value by a combination of the speed and acceleration of the operation lever when the speed of the operation lever exceeds a predetermined value. An actuator drive control device characterized by being variable. 7. The actuator drive control device according to claim 6, wherein the command value changing means changes the current command value in a range where the actuator does not move when the current command value is made variable. An actuator drive control device for outputting as an overcurrent value. 8. The actuator drive control device according to claim 6, wherein the command value changing unit determines whether a series of operations of the operation lever is completed, and determines whether the series of operations of the operation lever is completed. An actuator drive control device wherein the command current value is made variable only once. 9. The actuator drive control device according to claim 1, wherein said command value changing means determines that a series of operations is completed when said lever speed is equal to or less than a predetermined value. apparatus.