JPH08319638A - Driving controller for body to be worked - Google Patents

Abstract

PURPOSE: To detect abnormality quickly, and to stop a body to be worked at an early stage by providing a command input device, an actuator and a control means with a control arithmetic section and an output section. CONSTITUTION: Control levers 3, potentiometers 4, etc., are fitted to each of command input devices 2-1,... generating command signals to motor actuators 1-1,.... A control arithmetic section 9 arithmetically operates and outputs actuator driving command signals V01 ,... for driving each actuator 1-1,... on the basis of command signals V11 ,... input from the potentiometers 4,... for the command input devices 2-1,.... The trouble of the device 2 is detected by monitoring the command signal V11 and neutral signals N1 and ND1 by the arithmetic section 9, and a corresponding actuator stop signal DF1 is output at the time of trouble, thus forcibly interrupting the output line of the actuator driving command signal V01 regarding the device 2 getting trouble, then the corresponding actuator 1-1 is demagnetized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive control device for an object to be operated, which early stops an abnormality of a machine due to a failure of an internal circuit by self-diagnosis by a fail-safe method.

[0002]

2. Description of the Related Art In recent years, electronic control has been advanced also in the field of construction machines, and working machines have been driven and controlled by a microcomputer. In this type of construction machine, the displacement of the operating lever is converted into an electric signal by a potentiometer and input to a control circuit. The control circuit calculates actuator drive signals to be applied to each servo valve based on these input signals, and applies these drive signals to the solenoids of each servo valve via the current amplifier. In addition, this control circuit usually also performs a failure diagnosis of various electric circuits in the device, and when a failure is detected, the actuator drive signal is set to "zero" to stop the machine. There is.

However, in the above structure, when the current amplifying portion fails due to a short circuit or the like, for example, even if the actuator drive signal is set to "0", the current continues to be supplied to the solenoid and the actuator is stopped. do not do. And
As a result, a shortage occurs such as a runaway of the vehicle and an abnormal operation of the work machine. In such cases, the normal operation
It is conceivable that the engine will stop the runaway vehicle by stopping the engine by turning off the fuel supply lever and turning off the key switch to cut off the power supply to each electric circuit in the device.

By the way, in the construction machine, a relay is provided in the power supply line from the on-vehicle battery to each electric circuit, and the relay is cut off when the engine is completely stopped by the output of the alternator. Since it takes some time for the engine to completely stop after the fuel supply lever is cut off by the operator, the relay is turned off immediately when the fuel supply lever is cut off. However, there is some delay before being turned off. Therefore, during this time, power is supplied from the battery to the servo valve solenoid,
In the case of a short circuit of the current amplification section, the machine cannot be immediately stopped even if the fuel supply lever and the key switch are turned off.

[0005]

As described above, in the conventional apparatus, even if the fuel supply lever and the key switch are turned off, the power is continuously supplied to the circuit in the apparatus for a certain period of time. Cannot immediately stop the working machine and the vehicle, and therefore, there is a risk that a serious accident may occur due to a runaway of the vehicle, an abnormal operation of the working machine, or the like depending on a failure location. It is considered that such a failure of the electric circuit is inevitably increased in frequency as the number of electric components increases due to the enlargement of the electronic control system.

The present invention has been made in view of the above circumstances, and provides a drive control device for an actuated body capable of automatically and early stopping the working machine when a failure occurs in an electric circuit in the working machine. Is what you are trying to do.

[0007]

According to the present invention, there is provided a command input device having an operation lever and an output means for generating an operation signal corresponding to an operation amount of the operation lever, an actuator for driving an actuated body, and the command. An operation signal of an input device is input, and a control calculation unit that calculates a control signal of the actuator according to the input operation signal and an electric drive signal according to the control signal are generated and output to the actuator. In a drive control device for an actuated body, which comprises a control means having an output part, an abnormality detecting means for detecting an abnormality of at least one of the command input device and the control calculating part, and an abnormality detection of the abnormality detecting means. And a prohibiting means for prohibiting the driving of the actuator by a signal.

According to the above invention, when the abnormality detecting means detects an abnormality in either the command input device or the control calculation section, the actuator is prohibited from being driven. As a result, the operated body stops immediately.

Further, according to the present invention, a command input device having an operation lever and an output means for generating an operation signal according to an operation amount of the operation lever, an actuator for driving an actuated body, and an operation signal for the command input device. And a control means having an output unit for generating a current drive signal corresponding to the control signal and outputting the current drive signal to the actuator according to the input operation signal. In a drive control device for an actuated body comprising: an abnormality detection unit that detects an abnormality around the actuator and the output unit by a current drive signal generated from the output unit; and an abnormality detection signal of the abnormality detection unit A prohibition means for prohibiting the driving of the actuator is provided.

According to the present invention, an abnormality around the actuator and the output section is detected by a current drive signal generated from the output section, and when the abnormality is detected, the actuator is prohibited from being driven to operate. Stop your body. In this case, since the abnormality is detected by monitoring the current signal, it is possible to detect the abnormality with good accuracy even if the resistance value changes due to temperature change.

Further, according to the present invention, a command input device having an operation lever and an output means for generating an operation signal according to an operation amount of the operation lever, an actuator for driving an actuated body, and an operation signal for the command input device. And a control calculation unit that calculates a control signal of the actuator according to the input operation signal and an output unit that generates an electric drive signal according to the control signal and outputs the electric drive signal to the actuator. A drive control device for an actuated body, comprising: means for detecting an abnormality in at least one of the command input device, the control calculation unit, the actuator, and the output unit; When an abnormality detection signal is output from the abnormality detection unit, the power supply to the output unit of the control unit is cut off, Characterized in that it comprises a prohibiting means for prohibiting the driving of the actuator.

According to the present invention, when an abnormality is detected in any one of the command input device, the control calculation unit, the actuator and the periphery of the output unit, the power supply to the output unit of the control means is shut off. By doing so, the drive of the actuator is prohibited. As a result, the operated body stops immediately.

Further, according to the present invention, a command input device having an operation lever and an output means for generating an operation signal according to an operation amount of the operation lever, an actuator for driving an actuated body, and an operation signal for the command input device. And a control calculation unit that calculates a control signal of the actuator according to the input operation signal and an output unit that generates an electric drive signal according to the control signal and outputs the electric drive signal to the actuator. A drive control device for an actuated body comprising means, an abnormality detection means for detecting an abnormality of at least one of the command input device, the control operation part, the actuator and the periphery of the output part, When the abnormality detection signal is output from the abnormality detection means, a drive signal that does not cause the actuator to operate is output to the output section. And a prohibiting means for prohibiting the driving of the actuator by applying a force.

According to the invention, when an abnormality is detected in any one of the command input device, the control arithmetic unit, the actuator and the periphery of the output unit, the actuator does not operate in the output unit. By outputting a drive signal of a certain degree, the drive of the actuator is prohibited. As a result, the operated body stops immediately.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

An embodiment of the present invention will be described below with reference to an embodiment shown in the accompanying drawings.

FIG. 1 shows an example of the circuit configuration of an electronic control unit for construction machinery. The electronic control unit drives and controls a plurality of electric actuators 1-1, ..., 1-n.

These electric actuators 1-1, ..., 1
Reference numeral -n indicates, for example, solenoids, and by operating these solenoids, the direction and flow rate of the flow path of a solenoid valve (not shown) can be changed. By operating these solenoid valves, a hydraulic cylinder (not shown) is driven to expand and contract, and as a result, a work machine such as a bucket, a boom, a blade, an upper revolving structure, a traveling motor, etc., is driven. It will be. In this case, the electric actuators 1-1 and 1-
2 shall drive the boom up and down respectively,
It is assumed that this is operated by the command input device 2-1.

These electric actuators 1-1, ..., 1
A plurality of command input devices 2 for generating command signals for -n
Each of -1, ..., 2-m (m <n) is composed of an operation lever 3, a potentiometer 4, and a neutral sensor 5. The potentiometer 4 generates voltage signals VI1, VI2, ..., VIm corresponding to the displacement of the operation lever 3, and outputs them to the control calculation unit 9. The neutral sensor 5 is composed of a cam 6 having a concave portion that rotates in response to the displacement of the operation lever 3, a driven body 7, an electric contact 8 and the like,
The neutral state of the operation lever 3 is detected by these mechanical configurations, and the neutral signal NS1 has a logical value "1" when it is neutral and a logical value "0" when it is not neutral. , NS2, ..., NSm are output. Command signals VI1, ..., VIm output from these command input devices 2-1, ..., 2-m and neutral signals NS1 ,.
NSm is input to the control calculation unit 9. In addition, the news
The general signals NS1 to NSm are delayed by the delay circuits 13-1 to 13-.
m, respectively, and after being subjected to delay processing for a predetermined time respectively, as a signal ND1 to NDm, a control arithmetic unit 9 and a nogate 10 provided for each electric actuator.
Input to -1, ..., 10-n.

The control calculation unit 9 includes the command input devices 2-1 and 2-1.
..., 2-m potentiometers 4, ... Based on command signals VI1, ..., VIm input from each electric actuator.
, 1-n for driving the actuators 1-1, ..., 1-n, in addition to the operation of calculating and outputting the actuator drive command signals VO1, ... Do.

At this time, the control operation unit 9 operates the work machine with good responsiveness when the operation lever 3 is displaced from the neutral position to the work machine drive position, and the operation lever 3 is operated from the work machine drive side. When the actuator is displaced to the neutral position, the command signals VI1 to VIm input from the potentiometers 3 are given a predetermined delay so that the working machine operates slowly. The drive signals VO1 to VOn are output based on the command signal.

Further, the neutral detection in the control calculation unit 9 is performed by the command signal VI input from the potentiometer 3.
1 to VIm and the detection signal of the neutral sensor 5 are used. Therefore, the neutral sensor 5 side is provided so as to correspond to the command signal VI1, ... Is also provided with delay circuits 13-1, .... Further, during the abnormality detection processing in the control calculation unit 9, the neutral signal is not delayed, corresponding to the command signal VI having two types of signals, undelayed and delayed, and delayed with NS1 to nsm. Both ND1 to NDm are used.

The drive signals VO1 to VOn output from the control calculation unit 9 are deviation signals between the command signals VI1 to VIm and the feedback signal (not shown), for example.

, VOn are input to the amplifiers (output units) 12-1, ..., 12-n via the switch circuits 11-1, ..., 11-n, and after being amplified by the amplifiers. Each electric actuator 1-1, ..., 1-
n.

These electric actuators 1-1, ..., 1
The power supply to -n is the power line 20l1 to 20l3
Through. This power line 20l1 to 20l
3 is connected to an in-vehicle battery (not shown). A manual switch 14 and a relay 15 are provided on the power supply lines 2011 to 2013, and the power supply can be cut off by a dual structure of these. The battery side portion of the power supply line (not shown) is provided with the relay described in the conventional device.
Operates to disconnect the power line when the engine is stopped.

Whether or not the power is turned off by the manual switch 14 is detected by the detection circuit 16, and the detection circuit 16
Inputs a lever lock signal LR to the control calculation unit 9 which has a logical value of "1" when the manual switch 14 is not turned on (power is connected) and has a logical value of "0" when the manual switch 14 is turned on (power is disconnected) To do. The relay 15 is interrupted by the output signal of the nogate 16, and when the output of the nogate 16 is a logical value "0", its contact is turned off,
When the output of the switch 16 has the logical value "1", the contact is turned on.

The relay cutoff signal RE from the control arithmetic unit 9 and the arithmetic unit abnormality signal WDE from the arithmetic unit monitoring circuit 17 are input to the Nogate 16 and the Nogate 16 is input.
When either of these signals RE and WDE becomes the logical value "1", the output signal becomes "0" and the relay 15 is cut off (OFF). The relay cutoff signal RE is output from the arithmetic and control unit 9 when it is necessary to turn off the relay 15 to cut off the power supply due to some abnormality.

The arithmetic unit monitoring circuit 17 monitors the control arithmetic unit 9 for abnormalities. The arithmetic unit monitoring circuit 17 receives the monitoring pulse signal WD from the control arithmetic unit 9. In this case, the control arithmetic unit 9 outputs one pulse to the arithmetic unit monitoring circuit 17 each time the processing program for repeatedly performing diagnosis and abnormality detection is sequentially executed. Whether or not there is an abnormality in the arithmetic unit monitoring circuit 17 is determined by whether or not the pulse cycle of the use pulse signal WD is within a predetermined range.

That is, when the period of the monitoring pulse signal WD input from the arithmetic control unit 9 is out of the preset predetermined range, the arithmetic unit monitoring circuit 17 determines that the arithmetic control unit 9 is abnormal, At this time, the arithmetic unit abnormality signal WDE having the logical value "1" is output to the NOR gate 16. In addition, the abnormality of the relay 15 is the power line 2 after passing through the relay 15.
The voltage signal Vp of 013 is input to the control calculation unit 9, and this voltage Vp is detected by the control calculation unit 9 monitoring.

Further, nogates 10-1, ..., 10-n provided for each electric actuator are for switching the switch circuits 11-1 ,. Transmits the drive signal VO applied to the input side to the amplifier 12 when the output of the corresponding NOR gate 10 has the logical value "1", and disconnects the output line VO when the output of the NOAGE gate 10 has the logical value "0". Switch the contact so that it does.
However, zero voltage is applied to the amplifier in the disconnected state.

These Nogates 10-1, ..., 10-n
Is the operation unit abnormality signal W from the operation unit monitoring circuit 17.
Actuator stop signal DF from DE and arithmetic control unit 9
, DFn, and neutral signals ND1 to NDm from the neutral sensor 5 are input. The actuator stop signals DF1, ..., DFn are output from the arithmetic and control unit 9 when it is necessary to forcibly disconnect the output lines VO1 to VOm to stop the working machine due to some abnormality.

Each electric actuator 1-1, ..., 1-n
, 18-n for detecting the current value flowing through these actuators, respectively. The current detectors 18-1, ..., 18-n convert the voltage respectively. The detected values VF1, ..., VFn are input to the control calculation unit 9. Reference numeral 30 is an alarm device for alerting the operator of a device abnormality by means of a display or a buzzer.

That is, in this embodiment, the switch circuits 11-1, ..., 11-n forcibly disconnecting the command voltage output line are provided as a structure for emergency stop of the working machine.
An automatic interrupting relay 15 for shutting off the power source and a manual switch 14 for shutting off the power source by operating the operator are provided.

The operation of the above structure will be described below.

The control calculation unit 9 has five types of flag signals L.
ERFj, RERF, AERFi, INHFi and OE
Nj, and these flag signal and neutral signal NS
1 to NSm, their delay signals ND1 to NDm, the lever lock signal LR, the current detection signals VF1 to VFn, etc., and the output control of the relay cutoff signal RE and the actuator stop signals DF1 to DFn.

The flag signal LERFj (j = 1 to m) indicates an abnormality of the command input device 2-j, and the flag signal is provided for each of the m command input devices. The flag signal RERF indicates an abnormality of the relay 15, and when the relay 15 is abnormal, the flag signal RERF becomes "1". The flag signal AERFi (i = 1 to n) indicates an abnormality in the electric actuator section 1-i, the amplifier 12-i, the current detector 18-i, and the like. It is provided separately for each actuator. The flag signal INHFi indicates the abnormality of the relay 15 like RERF, but this flag IN
When HFi becomes "1", all the actuator stop signals DF1 to DFn are sent to cut off the supply of the drive signals VO1 to VOn, thereby cutting off the power supply and the drive signals VO1 to VOn. The actuator is stopped from both sides of the shutoff to improve the fail-safety. The flag signal OENj becomes "1" when the corresponding operation lever unit fails, and when the flag signal becomes "1", the control operation unit 9 outputs the corresponding actuator stop signal DFi. To "1" and output.

The control calculation unit 9 uses these flag signal, signals ND1 to NDm, and lever lock signal LR, and in accordance with the following logical expression, the relay cutoff signal RE and the actuator signal.
Output the stop signals DF1 to DFn. RE = LR + RERF (1) DFi = NDj + AERFi + INHFi + OENj (2) FIG. 2 shows an example of the abnormality detection processing procedure of the control calculation unit 9. The control calculation will be described with reference to this flow chart. The operation of the unit 9 will be described. This flow chart is roughly divided into three parts, which are a fault diagnosis of the operating lever, a fault diagnosis of the relay, and a fault diagnosis around the amplifier.

Prior to carrying out the abnormality detection processing, the control calculation section 9 carries out the aforementioned flag signals LERFj, RERF, AER.
Fi, OENj, relay cutoff signal RE, actuator stop signals DF1 to DFn, etc. are initialized (step 100). In this initialization, each flag signal is initialized to "0", and the signals RE and DF1 to DFn are initialized to the working machine stop side, that is, "1".

Fault Diagnosis of Operation Lever First, the control calculation unit 9 performs fault diagnosis of the command input device 2, that is, the operation lever unit.

The command input devices 2-1, ..., 2-m are of a half-duplex system as described above, and the control calculation unit 9 has command signals VIj (j = 1 to 1) from the potentiometer 4. m) and the neutral signal NSj from the neutral sensor 5
(J = 1 to m) are input respectively, and the control calculation unit 9 determines the failure of the operation lever based on these input signals. That is, as shown in FIG. 3, the control calculation unit 9 has three different set values V for determining the failure of the command input device 2.
1, V2 and V3 (V2 <V1 <V3) are set as positive and negative values, and the control calculation unit 9 sets these set values V
First, using 1 to V3, a failure diagnosis is performed for the command input device with j = 1 (step 110).

The control calculation unit 9 compares the absolute value of the command signal VI1 input from the potentiometer 4 with the command value V3 at the full stroke of the operation lever 3 (step 12).
0), | VI1 |> V3, for example, it is judged that the failure is caused by the disconnection of the lever harness or the ground fault, and the flag signal LER
F1 is set to "1" (step 130).

Further, when │VI1│≤V3, the control operation section 9 causes the command signal V to change when the neutral signal NS1 switches from "1" to "0" or from "0" to "1".
When I1 does not satisfy V2 <VI1 <V1, it is determined that the operation lever is defective due to the displacement of the potentiometer or the like.

That is, the control calculation section 9 judges whether the neutral signal NS1 is "0" or "1" (step 140),
When the signal NS1 is "0", the command signal VI1 is compared with the set value V2 (step 150), and the comparison result is |
When VI1│≤V2, it is determined that the operation lever has failed and the flag signal LERF1 is set to "1" (step 130). When | VI1│> V2, it is determined that the operation is normal.

When the neutral signal NS1 is "1" in the judgment of step 140, the control operation section 9 compares the command signal VI1 with the set value V1 (step 160). When the comparison result is | VI1 | ≥V1. Judges that the operation lever has failed, sets the flag signal LERF1 to "1" (step 130), and judges that it is normal when .vertline.VI1 .vertline. <V1. When the flag signal LERF1 becomes "1" by the above-mentioned failure diagnosis, the control operation unit 9 sets the command signal VI1 input from the command input device to neutral, that is, zero regardless of the input value, and thereafter the drive signal VO1 ... Output control and other internal processing, and the flag signal OEN1
Is set to "1" (step 170).

When this flag signal OEN1 becomes "1", the actuator stop signal (DF1 and DF2 in this case) corresponding to this command input device (2-1 in this case) becomes "1" in the subsequent step 380. As a result, the contacts of the switch circuits 11-1 and 11-2 are switched to the zero voltage side, the drive signal supplied to the amplifiers 12-1 and 12-2 becomes zero, and the corresponding electric actuator 1-
1 and 1-2 are deactivated.

Thereafter, the control operation unit 9 performs the same failure diagnosis for the command input device of j = 2 to m, and when an abnormality is detected, the flag signals LERF2 to LERFm are set to "1".
Then, by disconnecting the drive signal output line related to the command input device determined to be abnormal, the corresponding electric actuator is deactivated (step 180, step 19).
0, step 110, ...).

Fault Diagnosis of Relay Next, an abnormality detection process of the power shutoff relay 15 will be described.

First, in step 200, the flag signals INHF1 to INHFn are initialized.

Next, the control calculation section 9 causes the relay cutoff signal RE.
"0" and "1" are determined (step 210). This signal RE is "1" in the initial state, and the manual switch 14
Lever lock signal L associated with the connection (power line connection)
When the R "1" is input to "0", the power supply line is connected, and when the flag signal RERF becomes "1" thereafter, the power supply line is cut off again to "1" (step 38).
0).

When the signal RE is "1" in the judgment of step 210, the control operation part 9 supplies the power supply line 20.
The voltage value Vp of l3 is judged (step 220), and if the voltage value Vp is zero or a value in the vicinity thereof, it is judged that the power-off relay 15 is normal, and then all the flag signals INHF1 to INHFn are judged. Set to "1" (step 250).

As a result, in step 380, all the actuator stop signals DF1 to DFn are output as "1", whereby all the switch circuits 11-1 to 11-1 are output.
The contacts 11-n are switched to the zero voltage side, and the drive signals VO1 to VOn of the control calculator 9 are applied to the respective electric actuators 1-1.
~ 1-n is no longer supplied.

In step 220, the voltage value V
When it is determined that p is not zero or a value near zero, the control calculation unit 9 determines that a relay failure such as relay welding has occurred, and sets the flag signal RERF to "1" (step 240). ). As a result, in step 380, the relay cutoff signal RE becomes "1" and the relay 15 is turned off. In this state, a voltage is generated in the power supply line 20l3 even though the power cutoff relay 15 is cut off, which is highly dangerous. Therefore, the control calculation section 9 operates the alarm device 30 to notify the operator of the abnormality. By this abnormality report, the operator can turn on the manual switch 14, cut off the power supplied to each of the electric actuators 1-1 to 1-n, and stop the working machine in an emergency. Even in this case, the flag signal INHF
1 to INHFn are similarly set to "1", so that in step 380 the actuator stop signals DF1 to D are generated.
Fn is output and each electric actuator 1-1 to 1-n
Is not supplied with the drive signals VO1 to VOn.

When the relay cutoff signal RE is "0" in the judgment at step 210, the control operation unit 9 determines that the voltage value Vp of the power supply line 20l3 is the predetermined set voltage value V
It is determined whether or not it is larger than c (step 230).
If Vp ≦ Vc in this determination, the control calculation unit 9
Judges that the relay operation failure has occurred, and the flag signal RE
RF and INHF1 to INHFn are turned on (step 240, step 250). By turning on these flags, the power cutoff relay 15 is cut off thereafter, and the switch circuits 11-1 to 11-n are switched to the zero voltage side. If Vp> Vc in the determination of step 210, the relay 15 is determined to be normal, and the procedure proceeds to the next process, that is, the process of determining the abnormality of the electric circuit around the electric actuator 1-i.

Fault Diagnosis Around Amplifier First, the control calculation unit 9 determines the fault of the electric actuator 1, the switch circuit 11, the amplifier 12 and the current detector 18 for i = 1 (step 260).

In this failure determination, the control operation section 9 first determines whether the actuator stop signal DF1 is "0" or "1". Then, in this determination, the signal DF1 is "1".
If it is, the detected value VF1 of the current detector 18-1 is judged (step 280), and if VF1 is a value near zero, it is judged to be normal, and the procedure shifts to the process for i = 2 (step). 350).

Further, in the determination of step 280, VF
When 1 is not near zero, for example, a short circuit between the solenoid drive harness and the power supply line or a short circuit in the amplifier 12-1 is considered, and the control calculation unit 9 causes the flag signal AERF.
1 is set to "1" (step 290), and the flag signal R
The ERF is set to "1" (step 300). As a result,
In step 380, the relay cutoff signal RE and the actuator stop signal DF1 both become "1", and the relay 1
When 5 is turned off, the drive signal output line of the actuator 1-1 is disconnected.

When the signal DF1 is "0" in the judgment of step 270, the control operation section 9 refers to the drive signal VO1 and the current detection value VF1 at the present time, and the fourth
The abnormality determination is performed based on the relationship between the drive signal VOi and the detected current value VFi shown in the figure. In FIG. 4, the entire area is divided into three areas A, B, and C with the straight line VFi-VOi = VtH and the straight line VOi-VFi = VtL as the boundaries. It is determined to which of these three areas it belongs, and different processing is performed for each of the determined areas.

That is, according to the determination in step 310,
If it is the region C and whether or not the region C is determined,
Although disconnection of the solenoid drive harness, ground fault, etc. are conceivable, generally, in this case, the determination of the cause of the failure is ambiguous.
Both F are set to "1" (steps 290 and 300). As a result, the relay 15 is turned off and the actuator
The drive signal supplied to the controller 1-1 is cut off.

If the determination in step 310 is "NO", then it is determined whether the area is A or B (step 320). If it is determined to be the region B, it is determined that these device parts are normal, and the procedure shifts to the process for i = 2 (step 350). If it is determined to be in the area A, it is considered that the solenoid drive harness is shorted or the like. In this case, the control arithmetic unit 9 sets the flag signal AERF1 to "1" (step 330), and the failed amplifier The command signal VI1 input from the command input device (2-1 in this case) corresponding to the electric actuator (1-1 in this case) driven by the rear part is made neutral regardless of the input value. (Step 340).

In this case, the flag signal AERF1 is "1".
Therefore, in the subsequent step 380, the actuator stop signal DF1 becomes "1", and as a result, the drive signal VO1 supplied to the actuator 1-1 is cut off. In this state, the processing procedure of the control calculation unit 9 is returned from step 380 and the processing from step 110 is repeated again. However, in the next processing, the determination in step 270 is YES. , Then current detection value VF
i is examined (step 280).

At the time of the determination at step 280, if the detected current value VF1 is a value near zero, then the error flag is not turned on (step 350 ...). However, if the current detection value VF1 is not a value near zero in the determination of step 280, then the flag signal RERF is turned on (steps 290 and 300).

That is, when a failure occurs in the area A, the actuator stop signal (DF1 in this case) relating to the failed part is once output so that only the electric actuator (1-1 in this case) is demagnetized. After that, check the current value flowing through this electric actuator, and if the current value is near zero, stop outputting only this electric actuator thereafter, and drive signals to other electric actuators. To supply.

However, when the current value at the time of the check is not a value near zero, the relay cutoff signal RE is used to release the signal.
To turn off the power supply to all electric actuators.

Thereafter, the control calculation unit 9 performs the same failure diagnosis for the parts around the amplifier where i = 2 to n (steps 350, 360, 270, ...). Then, the control calculator 9 controls each electric actuator 1- based on the command signals VI1 to VIm input from the command input devices 2-1 to 2-m.
Drive signals VO1 to VOn for 1 to 1-n are calculated and output. At this time, the command signal which is judged by the failure diagnosis that the command should be stopped is treated as neutral, that is, zero, as described above.

Finally, the control operation unit 9 logically operates the relay cutoff signal RE and the actuator stop signal DFi in accordance with the logical expressions shown in the equations (1) and (2), and outputs these operation results (step 180). Such control is repeatedly executed while the work machine is driven.

The operation of the control operation unit 9 described above can be summarized as follows, which will be described together with the overall operation at the time of double failure and multiple failure.

(1) The detection of the failure of the command input device 2 is performed by monitoring the command signal VI and the neutral signals NS and ND by the control calculation section 9, and at the time of failure, the corresponding actuator stop signal is output. Actuator drive signal V related to the command input device 2 that has failed by outputting DF
Forcibly disconnect the O output line and demagnetize the corresponding electric actuator.

In this configuration, since the neutral signals ND1 to NDm are directly input to the NOR gates 10-1 to 10-n, the command input device 2, the arithmetic unit 9, the arithmetic unit monitoring circuit 17, Even if at least one of Noaget 16 and Relay 15 fails, the operation
If the operator performs an operation of returning the operation lever to the neutral position, the working machine associated with the operated operation lever can be stopped urgently.

(2) When the control arithmetic unit 9 has failed, the arithmetic unit monitoring circuit 17 detects this and turns off the power cutoff relay 15 by the signal WDE. As a result, all working machines are stopped. In the event of a double failure of the nogate 16 or relay 15 due to the failure of the control operation part 9, if the operator returns each operation lever to the neutral position as described above, the nogate As long as 10 and the amplifier 12 are normal, the working machine can be stopped.

(3) The failure of the Nogate 10, amplifier 12, electric actuator 1 and current detector 18 is detected by the control operation unit 9 monitoring the detected current value VF and the drive signal VO. (See FIG. 4).

When the failure occurs in the area A in FIG. 4, the control operation section 9 outputs the corresponding actuator stop signal DF, so that the drive signal V related to the part such as the failed amplifier 12 is generated.
Forcibly disconnect the output line of O and demagnetize only the corresponding electric actuator. If the detected current value VF flowing through the electric actuator becomes a proper value near zero due to this demagnetization, this state is maintained to stop only the working machine output related to the defective portion. However, when the current detection value VF does not become zero due to the demagnetization, the control calculation unit 9 outputs the relay cutoff signal RE to cut off the power supply and stop all working machines.

Further, since the determination of the failure state is ambiguous when the failure occurs in the area C, the control calculation section 9 causes the relay cutoff signal R
By outputting E, the power supply is cut off and all working machines are stopped.

(4) When the power cutoff relay 15 remains broken, the working machine does not operate, which is a safety failure. In this case, the control calculation unit 9 does not perform any special processing.

When a failure occurs in which the relay 15 remains in the conductive state due to the failure of the nogate 16 or the power cutoff relay 15 itself, the control arithmetic unit 9 cannot usually judge this. However, in this case, the control operation unit 9 can make a determination when a simultaneous failure occurs with other components such as the nogate 10 and the amplifier 12. That is, when the nogate 10 and the amplifier 12 fail, a relay cutoff signal RE that turns off the power cutoff relay 15 is eventually output from the control calculation unit 9. At this time, the relay cutoff signal RE is output.
Since the voltage VP on the output side is monitored, the control calculation unit 9 can detect an abnormality in the relay 15 or the nogate 16. In this case, the control calculation unit 9 notifies the operator by operating the alarm device 30. If the operator cuts off the manual switch 14 by this notification, the working machine is completely stopped.

In such a case, if the operator feels any abnormality from the operation of the machine, the working machine can be immediately stopped by shutting off the manual switch 14 by the operator.

(5) A simultaneous double failure between the potentiometer 4 and the neutral switch 5 or a simultaneous double failure between the amplifier 12 and the current detector 18 occurs with a very small probability. However, in this case, the operator may shut off the manual switch 14 according to the abnormality determination by the operator.

In the above embodiment, the logical form and the signal connection form are made to have some redundancy in consideration of the fail-safe property, but this point can be appropriately modified. Of course,

[0078]

As described above, according to the present invention,
Since the prohibiting means for prohibiting the driving of the actuator is provided and the prohibiting means is operated according to the diagnosis result of the command input device and the control calculation section, the actuated body can be automatically stopped early. As a result, the vehicle has runaway,
It is possible to prevent a serious accident due to an abnormal operation of the operated body.

Further, according to the present invention, an abnormality around the actuator and the output section is detected by the current drive signal generated from the output section, and when the abnormality is detected, the actuator is prohibited from driving so that the actuated body can be protected. Since it is stopped, it is possible to detect an abnormality with good accuracy even if the resistance value fluctuates due to a temperature change or the like.

Further, according to the present invention, when an abnormality is detected in any of the command input device, the control calculation unit, the actuator and the surroundings of the output unit, the power supply to the output unit of the control means is shut off. The actuator is prohibited from being driven by outputting a drive signal to the output unit to such an extent that the actuator does not operate. As a result, the actuated body can be automatically stopped at an early stage, and as a result, a serious accident due to a vehicle runaway or an abnormal operation of the actuated body can be prevented.

[Brief description of drawings]

FIG. 1 is a circuit block diagram showing an embodiment of the present invention.

FIG. 2 is a flow chart showing a specific operation example of a control calculation unit of the apparatus of this embodiment.

FIG. 3 is a diagram for explaining abnormality detection processing of a command input device.

FIG. 4 is a diagram for explaining abnormality detection processing of a portion such as an amplifier.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Electric actuator 2 ... Command input device 3 ... Operation lever 4 ... Potentiometer 5 ... Neutral sensor 6 ... Cam 7 ... Driven object 8 ... Electrical contact 9 ... Control computing unit 10, 16 ... Nogate 11 ... Switch circuit 12 ... Amplifier, 13 ... Delay circuit 14 ... Manual switch 15 ... Relay 17 ... Calculator monitoring circuit 18 ... Current detector 20l1 to 20l3 ... Power supply line 30 ... Alarm device.

Claims (5)

[Claims] 1. A command input device having an operation lever and output means for generating an operation signal according to an operation amount of the operation lever, an actuator for driving an actuated body, and an operation signal of the command input device. Control means for calculating a control signal of the actuator according to the input operation signal, and control means having an output portion for generating an electric drive signal according to the control signal and outputting the electric drive signal to the actuator. In the drive control device for an actuated body, an abnormality detecting unit for detecting an abnormality of at least one of the command input device and the control calculating unit, and the drive of the actuator is prohibited by an abnormality detection signal of the abnormality detecting unit. A drive control device for an actuated body, comprising: 2. A command input device having an operation lever and an output means for generating an operation signal according to an operation amount of the operation lever, an actuator for driving an actuated body, and an operation signal of the command input device. And a control unit having a control calculation unit for calculating a control signal of the actuator according to the input operation signal and an output unit for generating a current drive signal according to the control signal and outputting the current drive signal to the actuator. In a drive control device for an actuated body, abnormality detection means for detecting an abnormality around the actuator and the output portion by a current drive signal generated from the output portion, and driving the actuator by an abnormality detection signal from the abnormality detection means. A drive control device for an actuated body, comprising: a prohibiting means for prohibiting the. 3. A command input device having an operation lever and an output means for generating an operation signal according to an operation amount of the operation lever, an actuator for driving an actuated body, and an operation signal of the command input device. Control means for calculating a control signal of the actuator according to the input operation signal, and control means having an output portion for generating an electric drive signal according to the control signal and outputting the electric drive signal to the actuator. A drive control device for an actuated body, comprising: an abnormality detection unit that detects an abnormality in at least one of the command input device, the control calculation unit, the actuator and the periphery of the output unit, and the abnormality detection unit. When an abnormality detection signal is output from the actuator, the actuator is driven by cutting off the power supply to the output section of the control means. Drive control device of the actuating member, characterized in that it comprises a and a prohibiting means for prohibiting. 4. The operated body according to claim 3, wherein said prohibiting means has means for detecting an abnormality of said power supply cutoff means by monitoring a power supply voltage to an output part of said control means. Drive control equipment 5. A command input device having an operation lever and an output means for generating an operation signal according to an operation amount of the operation lever, an actuator for driving an actuated body, and an operation signal of the command input device. A control calculation unit that calculates a control signal of the actuator according to the input operation signal; and a control unit that has an output unit that generates an electric drive signal corresponding to the control signal and outputs the electric drive signal to the actuator. A drive control device for an actuated body, comprising: an abnormality detecting means for detecting an abnormality of at least one of the command input device, the control calculating portion, the actuator and the periphery of the output portion, and the abnormality detecting means. When an abnormality detection signal is output from the output unit, a drive signal that does not cause the actuator to operate is output to the output unit. Drive control device of the actuating member, characterized in that it comprises a and a prohibiting means for prohibiting the driving of the actuator.