JP3262236B2 - Control equipment for construction machinery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a construction machine capable of arbitrarily selecting an operation pattern of an operation lever.

[0002]

2. Description of the Related Art In a construction machine, desired operations are performed by appropriately operating left and right operation levers provided in a cab. Here, there are various types of operation patterns of the left and right operation levers according to applicable models and the like.
There are two types as shown in (a) and (b). As shown in the figure, the pattern shown in (a) performs the "turn left" operation when the left operating lever is operated in the direction of arrow A, whereas the pattern shown in (b) performs the same operation in the direction A. In this case, the actual operation is different even if the same operation is performed. Note that the black circle at the center of the operation pattern in the figure indicates a neutral (neutral) position.
By the way, there is a demand that such an operation pattern can be arbitrarily switched to a different one at a user or operator level, and various operation pattern switching devices have been considered to satisfy this demand.

FIG. 7 conceptually shows a configuration of a control device of a construction machine. Displacements of operation levers 91 and 92 are applied to a controller 90 via a signal line 93. The controller 90 creates a drive command for driving each work machine and outputs it to the solenoid valve group 95 via the signal line 94. The solenoid valve group 95 converts an electric signal into a hydraulic pressure, and supplies the hydraulic signal to a hydraulic operating valve 97 corresponding to each working machine via a hydraulic line 96 to drive each working machine.

[0004] First, the operation pattern is switched in the H section,
In other words, it is conceivable to perform this by switching the hydraulic pipeline 96. In this case, a so-called rotary switching valve for switching the PPC hydraulic pressure is used. It is also conceivable to switch the operation pattern by switching the portion of G, that is, the signal line 96. In this case, a rotary switch or the like for electrically switching between multiple contacts is used.

Further, various patent applications and the like for the purpose of fail-safe construction machines have been filed by the present applicant, and for example, there is a configuration shown in FIG.
3-142130). As shown in the figure, the displacement VI of the operation lever 3 in the left and right directions L and R is
And is added to the control operation unit 10. The direction in which the operation lever 3 is operated or whether the operation lever 3 is in the neutral position is determined by the left driven member 7R, the contact 8
R sensor 5 and right driven body 7L, contact 8L
The detection signals NR and NL are output from the respective sensors 5 '.

FIG. 5B shows such detection signals NR and NL. When the operation lever 3 is operated, for example, to the L side, the contact 8R is closed and the signal NR becomes "1" level. At the same time, the contact 8L is opened, and the signal NL becomes '0' level.

[0007] The detection signals NL and NR are applied to the switch circuits 20L and 20R via signal lines 8a and 8b, respectively. The switch circuits 20L and 20R output the detection signals NL and NR
Is in the ON state when is at the “0” level. For this reason, in the switch circuit 20L, for example, the drive signal VOL corresponding to the left-hand L operation output from the control operation unit 10 is made conductive, and the electric actuator 1L is output via the amplifier 30L.
To drive, for example, a left-turning working machine corresponding to the left-hand L operation (leftward turning). Conversely, when it is at the “1” level, the switch circuits 20L and 20R are turned off.
As a result, when the operation lever 3 is operated to the R side, the switch circuit 20L is turned off, and the drive signal VOL is cut off.
The electric actuator 1L is deenergized, and the corresponding work machine stops (stops turning left).

In such a configuration, the control operation unit 10 determines whether the operation lever unit 2 is abnormal.

That is, threshold values V1, V2 and V3 (maximum lever stroke) are set as shown in FIG. And 1) the detection signal VI of the potentiometer 4 is | VI |> V
When it becomes 3, it is determined that there is an abnormality such as disconnection of the lever harness.

2) When the detection signals NR and NL are switched from "1" to "0" or from "0" to "1", | V1 | <| V2 | <| V3 | , The operation lever unit 2 is determined to be abnormal due to the malfunction of the potentiometer 4 or the sensors 5, 5 '.

By the way, in the configuration of FIG. 4, when the operator detects an abnormality of the working machine due to a failure of the control operation unit 10 or the like, the working machine is operated by operating the operating lever 3 in the neutral position or in the opposite direction. It is designed to work on the safe side.

3) That is, for example, it is assumed that an abnormality occurs in which the working machine runs away to the R side while the operation lever 3 is displaced to the R side. At this time, if the operator performs the reverse lever operation of displacing the operation lever 3 to the L side, the signal NR becomes “1” (see FIG. 5B), and the runaway side switch circuit 20R is turned off. As a result, the supply of the drive signal VOR to the runaway-side actuator 1R is cut off, thereby avoiding an unexpected situation caused by the continuous supply of the drive signal to the runaway-side actuator. Also,
Japanese Patent Application Laid-Open No. 63-142129 also discloses a technique for shutting off a drive signal and operating a working machine on a safe side.

[0013]

By the way, in recent years, construction machines which perform various controls by arithmetic processing in a controller in order to increase added value of products have become mainstream. One example of this type of control is "priority mode"
This is, for example, a control mode for instructing any of the boom, arm, and turning work machines of the power shovel to increase the supplied oil amount.

When the above-described operation pattern switching technique is applied to this type of construction machine, the controller must always recognize the switched pattern, and simply sends switching information to the controller other than the switching contact at the subsequent stage of the controller. Requires contacts to transmit. Therefore, when switching is performed by G in FIG. 7, a large number of contacts, that is, 9 channels (4 positions), are required, and problems such as high cost and reduced reliability are actually caused. When switching is performed in H of FIG. 7,
This also requires high costs because it requires electrical contacts connected to the hydraulic rotary valve.

Also, when the operation pattern switching technique and the drive signal cutoff technique of the above 3) are implemented in combination, not only the switching of the electric signal line 94 or the hydraulic pipe 96 after the controller 90 but also the lever .. Provided for each operation direction need to be switched at the same time, and high cost and low reliability due to a large number of contacts are inevitable.

The present invention has been made in view of such a situation, and it is necessary to recognize an operation pattern switched in a controller. A drive signal is cut off for safety by a predetermined operation of a device and an operation lever indispensable for control. It is an object of the present invention to enable low-cost and highly-reliable switching of operation patterns by a device to be operated.

[0017]

Therefore, according to a first aspect of the present invention, a displacement of an operating means is detected.
In a drive control device for a work machine including a controller that outputs a drive signal corresponding to the detected displacement to an actuator corresponding to an operation direction, a plurality of different actuators corresponding to the operation direction of the operation unit are provided. A combination is set in advance, and a selecting means for selecting one of the plurality of combinations is provided,
When the selection content of the selection unit is input to the controller and a control mode for outputting a specific drive signal to a specific actuator is instructed, the controller performs the identification based on the input selection content. The operation direction of the operation means corresponding to the actuator is determined, and when the operation means is operated in the operation direction, a drive signal corresponding to the displacement of the operation means is set to the specific drive signal. , The corresponding actuator.

According to a second aspect of the present invention, there is provided a working machine having a controller for detecting a displacement of an operation means and outputting a drive signal corresponding to the detected displacement to an actuator corresponding to an operation direction. In the drive control device, a plurality of different combinations of the actuators corresponding to the operation directions of the operation means are set in advance, and a selection means for selecting one of the plurality of combinations is provided. A drive signal cutoff means for cutting off the supply of a drive signal to the actuator, and when the selection content of the selection means is input to the controller, the controller A drive signal is output to an actuator corresponding to the operation direction of the operating means being operated. In, the operation direction of the operating means that are currently operated to the driving signal cutoff means provided in the actuator corresponding to the reverse operation direction, and outputs a signal for operating the drive signal blocking means.

[0019]

According to the configuration of the first aspect, a plurality of different combinations of the actuators corresponding to the operation directions of the operation means are set in advance, and one of the plurality of combinations is selected by the selection means. When the selection content of the selection means is input to the controller and a control mode for outputting a specific drive signal to a specific actuator is instructed, the controller responds to the specific actuator based on the input selection content. The operating direction of the operating means to be operated is determined, and when the operating means is operated in the operating direction, a drive signal corresponding to the displacement of the operating means is set to a specific drive signal, and then the corresponding specific Output to the actuator.

According to the second aspect of the present invention, a plurality of different combinations of actuators corresponding to the operating directions of the operating means are preset, and one of the plurality of combinations is selected by the selecting means. . In addition, a drive signal blocking unit that blocks supply of a drive signal to the actuator is provided for each actuator. When the selected content of the selecting means is input to the controller, the controller outputs a drive signal to the actuator corresponding to the operation direction of the currently operated operating means based on the selected content, and simultaneously operates the currently operated one. A signal for operating the drive signal interrupting means is output to the drive signal interrupting means provided on the actuator corresponding to the operation direction opposite to the operation direction of the operating means being operated.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a control device for a construction machine according to the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of the embodiment.
It has a controller composed mainly of U12 and logic IC unit 13. The operation pattern selection switch 15 is provided outside the controller and is provided at a place where the operator can easily operate. In the embodiment, only the left operation lever will be described as a representative.

The power supply circuit 14 is a power supply for the entire apparatus.
Lever displacement detector 40 for detecting the operation amount in the A and B directions (see FIG. 6A) and the C and D directions (see FIG. 6A).
A voltage is applied to the lever displacement detection unit 45 for detecting the operation amount of the left operation lever 41, and an electric signal corresponding to the operation amount of the left operation lever 41 is generated. Also, a voltage is applied to the operation pattern selection switch 15. With the operation pattern selection switch 15,
Four types of contacts 15a and 15 are selected by the operator.
When any one of b, 15c, and 15d is switched, the light emitting elements (for example, LEDs) 16a, 16b, 16
One of the corresponding light emitting elements of c and 16d is turned on. At the same time, the signal lines 17a, 17b, 17c, 1
7d, a pattern selection signal indicating an operation pattern selected via any signal line corresponding to the switched contact is output to the CPU 12, and the logic I
It is output to the C unit 13.

By the way, there are four different operation patterns to be selected corresponding to the four contacts 15a to 15d, respectively. For example, the contact 15a has a pattern shown in FIG. Pattern)
However, it is assumed that the pattern shown in FIG. 6B (hereinafter, referred to as a second pattern) corresponds to the contact 15b. Therefore, when the contact 15a is selected, a signal '1' indicating the first pattern is sent to the CPU via the signal line 17a.
13 and the other signal lines 17b to 17
The signal of d becomes '0'. Therefore, the logic IC unit 13
Is input with pattern data having a logical structure of "1000" (in the order of the signal lines 17a to 17d).

The lever displacement detector 40 includes two resistors 4
A voltage corresponding to the sliding position of 3, 44 is output, and the sliding position is determined by the moving position of the connecting member 42 connected to the left operating lever 41. That is, assuming that the operation lever 41 is operated in the direction A, the connecting member 42 moves in conjunction with this operation. Connecting member 42
Acts as a slider on the two resistors 43, 44 to increase the voltage generated by the respective resistors 43, 44.
Conversely, when the operation lever 41 is operated in the B direction, the resistance 4
The voltage generated by 3, 44 is reduced. The lever detection unit 45 is similarly configured, and the operations in the C and D directions are A,
The relationship is the same as the operation in the B direction. Resistance 43, 44
The voltage corresponding to the change in the sliding position is output to the CPU 12, and the voltage of one resistor 44 is compared with the voltage of the comparator 50, 5.
1 is output.

The comparator 50 determines whether the voltage corresponding to the sliding position of the resistor 44 is equal to or higher than a predetermined threshold. That is, when the operation lever 41 is operated in the A direction from the neutral position, the voltage becomes equal to or higher than the threshold value, and a signal '1' indicating that the operation is performed in the A direction is output. On the other hand, when the operation lever 41 is operated in the neutral position or the B direction, the voltage becomes smaller than the threshold value, and a signal “0” indicating that the operation is operated in the neutral position or the B direction is output.

Similarly, the comparator 51 determines whether the voltage corresponding to the sliding position of the resistor 44 is equal to or higher than a predetermined threshold. That is, when the operation lever 41 is operated in the neutral position or the A direction, the voltage becomes equal to or higher than the threshold value, and a signal “0” indicating that the operation is operated in the neutral position or the A direction is output. On the other hand, when the operation lever 41 is operated in the B direction, the voltage becomes smaller than the threshold value, and a signal “1” indicating that the operation is performed in the B direction is output.

Comparator 5 corresponding to lever displacement detector 45
2 and 53 have the same configuration as the comparators 50 and 51, and the C and D directions of the lever 41 (including the neutral position).
The signals output from the comparators 52 and 53 according to the operation are:
The relationship is the same as the signals output from the comparators 50 and 51 in response to the operation of the lever 41 in the A and B directions (neutral position).

Therefore, assuming that the operation lever 41 is operated in the direction A, the signal '1' from the comparator 50 is
The other comparators 51, 52, and 53 output a signal '0', and the logic IC unit 13 outputs “1000”.
(Operation directions A, B, C, and D) are input as operation direction data having a logical structure.

The CPU 12 compares the voltage signals output from the resistors 43 and 44 of the lever displacement detecting section 40 to determine whether the lever portion is abnormal, as will be described later. A similar abnormality determination is made based on each resistance of the lever displacement detection unit 45. The CPU 12 is connected to the signal line 17a.
Abnormality determination of the operation pattern selection switch 15 is performed based on the logical structure of the pattern data input through .about.17d, which will also be described later.

When the CPU 12 determines that an abnormality has occurred, the CPU 12 performs a process of sounding a buzzer 18 or a process of turning on a lamp 19 to warn the operator of the abnormality, thereby ensuring safety. If the lever portion is abnormal, the drive signal supplied to the electric actuators corresponding to the lever displacement detectors 40 and 45 determined to be abnormal is forcibly reduced to zero, thereby ensuring safety. I have.

Further, the logic IC section 13 detects an abnormality of the operation pattern selection switch 15 when the logical structure of the pattern data is a predetermined logical structure, and when all the switch circuits 30R, 30L. The signals to be turned off are output to the delay circuits 60, 61,.

Now, the electric actuators 1L, 1R
An electric actuator that drives a work machine for turning,
1L corresponds to “turn left” and 1R corresponds to “turn right”. The electric actuator 1L has a switch circuit 20L,
A drive signal is input from the CPU 12 via the amplifier 30L. The switch circuit 20L is turned on in response to signals “1” and “0” input through the delay circuit 60, respectively.
It turns off and conducts and cuts off the drive signal. The delay circuit 61, the switch circuit 20R, and the amplifier 30R corresponding to the electric actuator 1R have the same configuration.

The electric actuators 11L, 11R
Is an electric actuator for driving the arm, and 11
L corresponds to “arm dump”, and 11L corresponds to “arm excavation”. Delay circuit 62 corresponding to electric actuator 11L, switch circuit 21L, amplifier 31L and delay circuit 6 corresponding to electric actuator 11R
3. The switch circuit 21R and the amplifier 31R have the same configuration.

The delay circuit 60 outputs the signal "1" when the signal "1" is input from the logic IC unit 13, but when the input signal changes from "1" to "0",
The signal '0' is output after being delayed by a predetermined time td (see FIG. 3C). Other delay circuits 61, 62, 6
The same applies to No. 3.

Hereinafter, the processing performed by the CPU 12 and the processing performed by the logic IC unit 13 will be described.

When the first pattern is selected by switching to the contact 15a by the operation pattern selection switch 15, the CPU 12 determines the operation directions A, B, C, and D from the logical structure of the pattern data "1000". The association with the actuators 1L, 1R, 11L, and 11R is performed.

When the value is "1000", the correspondence is as follows: A = 1L (turn left), B = 1R (turn right), C = 11L (arm dump), D = 11R (arm excavation) (1) (See FIG. 6A).

When the contact is switched to the contact 15b and the second pattern is selected, pattern data "0100" is input.
R (arm excavation), B = 11L (arm dump), C =
1L (left turn), D = 1R (right turn) (2) are associated (see FIG. 6B).

When another pattern is selected, that is, the contacts are switched to the contacts 15c and 15d, and "0010", "00"
01 "is input.
As in the case of the expressions (1) and (2), a predetermined association is made according to the contents of the logical structure. The logic IC unit 13 also uses the comparators 50 to 53 and the delay circuits 60 to 53 based on the input pattern data.
63 is associated. Here, the comparators 50, 5
The levers 41, 52, and 53 are A, B, C, and D, respectively.
These are comparators for A, B, C, and D operation directions, respectively, which output a signal '1' operated in the direction when operated in the direction. On the other hand, the delay circuits 60, 61, 6
Reference numerals 2 and 63 denote delay circuits corresponding to the actuators of “turn left”, “turn right”, “arm dump”, and “arm excavation”, respectively.

Therefore, when the pattern data is "1000", the comparator 50 (A) = delay circuit 60 (left turn) and the comparator 51 (B) = delay circuit 61 (corresponding to the above equation (1)). (Turn right), comparator 52 (C) = delay circuit 62 (arm dump), comparator 53 (D) = delay circuit 63 (arm excavation) (3).

When the pattern data is "0100", the comparator 50 (A) = delay circuit 63 (arm excavation) and the comparator 51 (B) = delay circuit 62 corresponding to the above equation (2). (Arm dump), comparator 52 (C) = delay circuit 60 (turn left), comparator 53 (D) = delay circuit 61 (turn right) (4).

When another pattern is selected, that is, the contacts are switched to the contacts 15c and 15d, and "0010", "00"
The same association is made when data having a logical structure of “01” is input.

Then, the first pattern is now selected,
It is assumed that the operator operates the operation lever 41 in the A direction to make a “turn left”. First, the contact 15a is turned on, and the light emitting element 16a is turned on. This allows the operator to recognize that the first pattern has been selected.

When the lever 41 is operated in the direction A, the comparator 50
Outputs a signal '1', and the signal '1' is applied to the delay circuit 60 via the logic IC unit 13 (see the above equation (3)). The signal '0' output from the other comparators 51, 52, 53 is applied to the delay circuits 61, 62, 63 via the logic IC unit 13, respectively.

As a result, the signal '1' is output from the delay circuit 60, the switch circuit 20L is turned on,
Actuator 1L corresponding to operation direction A from PU12
Is supplied with a drive signal VOL. Signals "0" are output from the other delay circuits 61 to 63, the switch circuits 20R to 21R are turned off, and the actuators 1R to 11 corresponding to the operation directions B, C, and D different from the A operation direction.
The drive signal supply path to R is shut off (see the above equation (3)).

The CPU 12 detects that the operation lever 41 is being operated in the direction A by increasing the detection voltage of the displacement detection unit 40, and generates a drive signal VOL corresponding to the magnitude of the detection voltage. This is supplied to the actuator 1L corresponding to the A operation direction via the switch circuit 20L and the amplifier 30L which are currently turned on (see the above equation (1)). For this reason, the construction machine turns left at a speed corresponding to the operation amount of the operation lever. On the other hand, since the detection voltage of the displacement detection unit 40 is increased, it is detected that the operation is not performed in the B direction, and the displacement detection unit 4
It is detected that the detection voltage of No. 5 indicates the neutral position, and the drive signal supply to the actuators 1R, 11L, 11R corresponding to the operation directions B, C, D different from the operation direction A is turned off ((1) above). ) Expression).

The CPU 12 performs various control modes based on the input pattern data. For example, when executing the “priority mode”, if the current rotation motor is instructed to increase the supply oil amount, the operation directions corresponding to the “turn” are A and B from the pattern data. (Expression (1)) above, when the lever 41 is operated to A or B, a drive signal for increasing the amount of supplied oil is output to the corresponding actuator 1L or 1R.

If the operator detects an abnormality in such a state, the operator operates the operating lever 4 to avoid danger.
1 is operated in the neutral position or in the B direction opposite to the current A operation direction. When the operation of returning the operation lever 41 to the neutral position is performed, the output signal of the comparator 50 changes from “1” to “0”. The delay circuit 60 outputs a signal that changes from “1” to “0” with a delay of td from the point of change of the input signal “1” → “0”. For this reason, the switch circuit 20L is slowly turned off, and the left turning operation is stopped slowly without a shock. Further, for example, it is assumed that an abnormality occurs in which the turning work machine runs away to the left while the operation lever 41 is displaced in the direction A. At this time, if the operator performs the reverse lever operation of displacing the operation lever 41 to the B side, the output signal of the delay circuit 60 becomes “0” after the delay time td, and the output signal of the delay circuit 61 becomes “1”. 'become.

As a result, the switch circuit 20L on the runaway side is slowly turned off, the supply of the drive signal VOL is slowly cut off to the actuator 1L on the runaway side, and the operation lever is turned on the actuator 1R on the opposite side. A drive signal VOR corresponding to the displacement of the reference numeral 41 is supplied. Thus, the work implement is driven in the direction opposite to the runaway direction, and the runaway of the work implement can be quickly decelerated and stopped.

The CPU 12 takes in both voltages according to the sliding positions of the resistors 43 and 44 of the lever displacement detecting section 40,
The abnormality determination of the lever displacement detection unit 40 is performed.

That is, if the lever displacement detecting section 40 is operating normally, the values of the two voltages are the same or within a predetermined deviation. Therefore, when the difference between the two voltages is equal to or greater than a predetermined threshold, the lever displacement detecting unit 40
It is determined that an abnormality such as a failure has occurred. If it is determined that an abnormality has occurred, the CPU 12 determines whether the lever displacement detector 40
The drive signals VOL and VOL supplied to the electric actuators 1L and 1R corresponding to
L and R are deenergized and the turning operation is forcibly stopped for safety. Further, a process for operating the buzzer 18 or the lamp 19 is performed to notify the operator of the abnormality.

In this regard, the conventional lever portion abnormality determination is based on the fact that the output signals of the neutral position sensors 5, 5 'change from "1" to "0" or from "0" to "1" as described above with reference to FIG. Can be determined only in the vicinity of the neutral position. However, in the embodiment, the abnormality is determined over the entire range in which the lever 41 is displaced, and the reliability of the abnormality detection is improved.

The CPU 12 is provided with a lever displacement detector 45.
The same abnormality detection is also performed based on each output voltage of the lever displacement detection unit 4 when it is determined that there is an abnormality.
Actuators 11L corresponding to the five operation directions C and D,
Deactivate 11R, stop arm drive,
By operating the buzzer 18 or the lamp 19, the operator is notified of the abnormality of the lever displacement detector 45.

Next, it is assumed that the operation pattern selection switch 15 is switched to the contact 15b by the operator's selection, and the second pattern is selected. As a result, the contact 15
b is turned on, the light emitting element 16b is turned on, and the operator can recognize that the second pattern is selected.

In the second pattern, the operator operates the lever 41 in the direction A to perform "arm excavation".
With this operation, a signal '1' is output from the comparator 50,
This signal '1' is applied to the delay circuit 63 via the logic IC unit 13 (see the above equation (4)). The signal '0' output from the other comparators 51, 52, 53 is transmitted to the delay circuits 62, 6 via the logic IC unit 13, respectively.
0, 61 are added. Thereby, the delay circuit 6
3, a signal '1' is output, the switch circuit 21R is turned on, and a drive signal is supplied from the CPU 12 to the actuator 11R corresponding to the A operation direction. A signal '0' is output from the other delay circuits 60, 61, and 62, and the switch circuits 20L, 20R, and 21L are turned off.
The drive signal supply paths to the actuators 1L, 1R, and 11L corresponding to the operation directions C, D, and B different from the operation direction A are shut off (see the above equation (4)).

The CPU 12 detects that the operation lever 41 is operated in the direction A, generates a drive signal corresponding to the magnitude of the detected voltage, and turns on the drive signal. Is supplied to the actuator 11R corresponding to the operation direction A via the above (refer to the above equation (2)). Therefore, the arm is driven in the excavation direction at a speed according to the operation amount of the operation lever. On the other hand, the displacement detector 40
Is detected not to be operated in the B direction based on the detected voltage of the operation direction, and the neutral position is detected based on the detection voltage of the displacement detection unit 45, and the operation directions C and D different from the A operation direction are detected. , B, the drive signal supply to the actuators 1L, 1R, 11L is turned off (see the above equation (2)). Here "Priority mode"
If it is currently instructed to increase the supply oil amount to the arm cylinder, it is known from the pattern data that the operation directions corresponding to the "arm" are A and B (formula (2) above). When the lever 41 is operated to A or B, a drive signal for increasing the supply oil amount is output to the corresponding actuators 11R and 11L.

When the operator detects an abnormality in such a state, the operator operates the operating lever 4 to avoid danger.
1 is operated in the neutral position or in the B direction opposite to the current A operation direction. When the operation of returning the operation lever 41 to the neutral position is performed, the output signal of the comparator 50 changes from “1” to “0”. The delay circuit 63 outputs a signal that changes from “1” to “0” with a delay of td from the point of change of the input signal “1” → “0”. For this reason, the switch circuit 21L is slowly turned off, and the arm excavation operation is stopped slowly without a shock. Further, it is assumed that, for example, an abnormality occurs in which the arm runs away in the excavation direction while the operation lever 41 is displaced in the direction A. At this time, if the operator performs the reverse lever operation of displacing the operation lever 41 to the B side, the output signal of the delay circuit 63 is equal to the delay time td.
At the same time, the output signal of the delay circuit 62 becomes "1".

As a result, the switch circuit 21R on the runaway side is slowly turned off, the supply of the drive signal to the actuator 11R on the runaway side is slowly cut off, and the operation lever 4 is connected to the actuator 11L on the opposite side.
A drive signal corresponding to the displacement of 1 is supplied. Then
The arm is driven in the dump direction opposite to the runaway direction, so that the runaway of the arm can be quickly decelerated and stopped.

The CPU 12 determines whether the lever displacement detector 40 is abnormal based on both voltages corresponding to the sliding positions of the resistors 43 and 44 of the lever displacement detector 40.

That is, when the difference between the two voltages is equal to or greater than a predetermined threshold value, it is determined that the voltage is abnormal and the electric actuators 11R, 1R,
The drive signal supplied to 1L is made zero to deactivate the electric actuators 11R and 11L, and the arm drive is forcibly stopped for safety. In addition, the buzzer 18 or the lamp 19 is operated to notify the operator of the abnormality. Similar abnormality detection is also performed based on each output voltage of the lever displacement detection unit 45. If it is determined that an abnormality has occurred, the actuator 1 corresponding to the operation direction C or D of the lever displacement detection unit 45
L and 1R are deenergized and the turning operation is stopped.
By operating the buzzer 18 or the lamp 19, the operator is notified of the abnormality of the lever displacement detector 45.

The same processing is performed when another pattern is selected by the operation pattern selection switch 15.

As described above, according to the embodiment, the operation direction of the operation lever is automatically associated with each actuator in accordance with the selection of the operation pattern, so that the supply and cutoff of the drive signal and the abnormality determination are performed accurately and accurately. It will surely be done.

By the way, the operation pattern selection switch 15 itself may be in an abnormal state such as failure due to a defective contact or harness.

However, in this embodiment, four light emitting elements 16a to 16d are provided corresponding to the four operation patterns to be selected, respectively, and there is redundancy. Therefore, the operator can easily and reliably determine the abnormality of the selection switch 15 from the lighting state of the four light emitting elements 16a to 16d. For example, if two or more light emitting elements are turned on or none of them is turned on even though one pattern is selected, it is determined that the light emitting element is abnormal.

The pattern data is stored in the logic IC unit 1.
3, a logical structure indicating that two or more patterns are selected (for example, “1100”), or a logical structure in which none of the patterns are selected (“000”).
0 "), the operation pattern selection switch 15
Is determined to be abnormal, and each switch circuit 2 is turned off to deactivate the electric actuators 1L to 11R for safety.
A signal '0' for turning off 0L to 21R is output to each of the delay circuits 60 to 63.

The CPU 12 similarly determines an abnormality on the basis of the input pattern data. If the abnormality is determined, the CPU 12 operates the buzzer 18 or the lamp 19 to warn the operator. Further, for safety, a process of forcibly turning off the drive signal is performed regardless of the operation state of the lever 41.

It should be noted that various modifications are possible without being limited to the configuration shown in FIG. For example, instead of the lever displacement detection unit 40 in FIG. 1 in which both voltages increase (or decrease) simultaneously according to the lever operation, as shown in FIG. 2A, the two resistors 43 and 44 generate the voltage according to the lever operation. It is also possible to use a lever displacement detector 46 configured to increase and decrease the applied voltage, respectively. Since the two output voltages change in the same direction, the lever displacement detection unit 40 may not be able to detect an abnormality when the two voltages are shifted by the same amount. However, in the lever displacement detecting section 46, even if the two voltages are displaced by the same amount, the directions in which the two voltages change are opposite to each other.

Further, as shown in FIG. 9B, it is also possible to execute the process of cutting off the drive signal depending on the judgment of the operator.

In FIG. 9B, a changeover switch 70 is a switch for selecting whether or not to execute a drive signal cutoff process. Therefore, the switch 70 is executed to execute the same processing.
Are switched to the contact 70a, a signal '0' is applied to one input terminal of the OR circuits 71, 72... Therefore, the delay circuits 60, 61,.
When a signal '0' for turning off the L, 20R is output and applied to the other input terminal of the OR circuits 71, 72,..., The switch circuits 20L,
Is turned off, and the drive signal supply path is cut off.

On the other hand, when the operator decides not to execute the drive signal cutoff process and switches to the contact 70b, a signal '1' is applied to one input terminal of the OR circuits 71, 72,. .., Always output a signal '1'.
. 0L, 20R... Are turned on, and the drive signal supply path is not interrupted.

The changeover switch 70 can be disposed at a place where it can be immediately operated, such as the grip portion of the operation lever, so that the changeover switch 70 can be operated only when the operator is operating the operation lever. In other words, it is possible to avoid a situation in which the contact is switched to the contact 70b except during the operation of the lever and safety is impaired.

The lever displacement detectors 40, 4 of the embodiment
It is also possible to use a sensor of the operation lever unit 2 shown in FIG.

In some cases, the buzzer 18 and the lamp 19 for warning the operator may be omitted. Similarly, an embodiment in which the delay circuits 60 to 63 are omitted as appropriate is also possible.

It is also possible to carry out the drive signal cut-off processing, in which case the logic IC 13, the switch circuit 20L, etc. can be omitted.

It is also possible to carry out the operation without selecting the operation pattern itself. In this case, the comparators 50.
And the delay circuit 60... Are fixed,
The logic IC unit 13 can be omitted.

Further, it is also possible to carry out the present invention by appropriately combining the technology disclosed in this embodiment with the safety technology described in JP-A-63-142129.

Further, it is also possible to appropriately combine the technology disclosed in the embodiment with the configuration (FIG. 4) described in JP-A-63-142130. For example, FIG.
3B, delay circuits 80 and 81 similar to the delay circuit 60 may be interposed on the signal lines 8a and 8b to perform a similar slow stop operation. Good. In this case, as shown in FIG. 3B, when the operation lever 3 is operated to the neutral position or the R side due to runaway of the L side, for example, a signal '1' is output from the sensor 5 '( Time t0). Then, time t
At time t1 delayed by d, the signal '1' is output from the delay circuits 80 and 81, the abnormal side switch circuit 20L is slowly turned off, and the abnormal side actuator 1L is slowly deenergized. Becomes

[0079]

As described above, according to the present invention, the selection of the operation pattern is input to the controller and the control according to the selection is performed, so that the selected operation pattern can be recognized. It is easy to apply to devices that are indispensable for control and devices where the drive signal is cut off for safety by the predetermined operation of the operation lever, and the changeover switch is simpler than the conventional one that switches the signal line at the subsequent stage of the controller This makes it possible to reduce costs and improve reliability against failure.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of a control device for a construction machine according to the present invention.

FIGS. 2A and 2B are diagrams showing an example in which a part of the embodiment shown in FIG. 1 is replaced with another configuration.

3A is a diagram showing an example in which a delay circuit is inserted into a portion E in FIG. 4, and FIG. 3B is a time chart showing a relationship between an input signal and an output signal of the delay circuit in that case; It is a chart. FIG. 3C is a time chart showing the relationship between the input signal and the output signal of the delay circuit of FIG.

FIG. 4 is a diagram showing a configuration of a conventional technique.

FIG. 5 is a graph showing the operation of the device shown in FIG.

FIGS. 6A and 6B are diagrams illustrating an operation pattern; FIG.

FIG. 7 conceptually shows a configuration of a control device of a construction machine using a so-called electric / hydraulic conversion valve, and is a diagram used for explaining a conventional technique.

[Explanation of symbols]

 1L electric actuator 1R electric actuator 11L electric actuator 11R electric actuator 12 CPU 13 IC logic unit 15 operation pattern selection switch 20L switch circuit 20R switch circuit 21L switch circuit 21R switch circuit 40 lever displacement detection unit 45 lever displacement detection unit

Claims (6)

(57) [Claims] 1. A work machine comprising: a plurality of hydraulic actuators; and operating means operated in a plurality of operating directions, wherein the working machine drives a hydraulic actuator corresponding to the operating direction of the operating means among the plurality of hydraulic actuators. A plurality of operation patterns different in hydraulic actuator corresponding to the operation direction of the means are set in advance, and an operation pattern selecting means for selecting one operation pattern among the plurality of operation patterns; Priority mode instructing means for instructing a priority mode for changing the amount of oil supplied to the hydraulic actuator, and irrespective of the selection of the operation pattern, for a specific hydraulic actuator instructed by the priority mode instructing means. The priority mode instructing means so that the pressure oil of the changed oil amount is supplied. A working machine characterized by associating a specific hydraulic actuator designated by (1) with an operation direction of the operation means for each operation pattern. 2. A drive control device for a work machine, comprising: a controller configured to detect a displacement of an operation unit and output a drive signal corresponding to the detected displacement to an actuator corresponding to an operation direction. A plurality of different combinations of the actuators corresponding to the operation directions of the means are set in advance, and a selection means for selecting one of the plurality of combinations is provided. And a drive signal cut-off unit that cuts off supply of the control unit. When the selection content of the selection unit is input to the controller, the controller operates the operation unit that is currently operated based on the selection content. Outputs a drive signal to the actuator corresponding to the direction and is currently operated. A drive control device for a working machine, which outputs a signal for actuating the drive signal cutoff means to a drive signal cutoff means provided on an actuator corresponding to an operation direction opposite to the operation direction of the operation means. . 3. A drive control device for a work machine, wherein a displacement of the operating means is detected and an actuator corresponding to an operating direction is drive-controlled in accordance with the detected displacement. A plurality of displacement detection means for detecting an operated displacement, and when the difference between the plurality of displacements output from the plurality of displacement detection means is equal to or greater than a predetermined threshold, the operation means is abnormal. A drive control device for a work machine, which determines that there is a work machine. 4. A drive control device for a work machine, wherein a displacement of an operation means is detected and an actuator corresponding to an operation direction is drive-controlled in accordance with the detected displacement. When the operation is performed, the displacement signal outputs a displacement signal in which the level of the displacement amount increases in accordance with the amount of the operation in conjunction with the operation, and a displacement signal in which the level of the displacement amount decreases in accordance with the amount of the operation. A drive control device for a working machine, comprising: signal output means; and determining an abnormality of the operation means based on the displacement signals. 5. The drive control device for a work machine according to claim 2, further comprising a selection unit that selects whether or not to execute a cutoff process by said drive signal cutoff unit. 6. A drive control device for a working machine, comprising: a controller for detecting a displacement of an operation means and for driving and controlling an actuator corresponding to an operation direction in accordance with the detected displacement. Selecting means for selecting one of a plurality of different combinations of the corresponding actuators and outputting a selection signal; inputting a selection signal output from the selection means, and determining an abnormality of the selection signal based on the selection signal. A CPU that performs a determination process using software; and a logic IC unit that receives a selection signal output from the selection unit and performs a process of determining an abnormality of the selection signal based on the selection signal using a logic circuit. As a result of the CPU and the IC logic unit performing a process of determining the abnormality of the selection signal, the CPU or the IC logic unit At least on the other hand, when it is determined that the selection signal is abnormal, the CPU or the IC logic unit that has determined that the selection signal is abnormal performs control to turn off a signal for driving each actuator. A drive control device for a work machine.