JP2579152B2 - Actuator drive control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuated body drive control device that stops an abnormal operation of a machine due to a failure in an internal circuit or the like early by a self-diagnosis by a fail-safe method. is there.

[Conventional technology]

In recent years, electronic control has been advanced in the field of construction machinery,
The working machine is driven and controlled by a microcomputer. In this type of construction machine, the displacement of the operation lever is converted into an electric signal by a potentiometer and input to a control circuit. The control circuit calculates an actuator drive signal to be applied to each servo valve based on these input signals, and applies these drive signals to the solenoid of each servo valve via a current amplifier. In addition, the control circuit normally performs a failure diagnosis of various electric circuits in the apparatus. When a failure is detected, the actuator drive signal is set to “zero” to stop the machine.

However, in the above configuration, for example, when the current amplifying unit fails due to a short circuit or the like, even if the actuator drive signal is set to “zero”, the current continues to be supplied to the solenoid, and the actuator does not stop. And as a result,
Insufficient situations such as runaway of the vehicle and abnormal operation of the work machine occur. In such a case, the operator usually stops the engine by turning off the fuel supply lever, and cuts off the power supply to each electric circuit in the device by turning off the key switch to forcibly stop the runaway of the vehicle. Conceivable. By the way, in construction machinery, a relay is provided on the power supply line from the onboard battery to each electric circuit,
This relay is shut off when the engine is completely stopped by the output of the alternator. Here, since it takes some time from when the fuel supply lever is turned off by the operator to when the engine is completely stopped, the relay is not turned off immediately when the fuel supply lever is turned off, but is turned off. There is some time delay before. For this reason, during this time, power is supplied from the battery to the solenoid of the servo valve, and in the case of a short circuit of the current amplifying unit or the like, even if the fuel supply lever and the key switch are turned off, the machine is immediately operated. Cannot be stopped.

[Problems to be solved by the invention]

As described above, in the conventional device, even if the fuel supply lever and the key switch are turned off, the power supply to the device circuit is continuously supplied for a certain period of time, so that the work implement and the vehicle can be immediately stopped by the above operation. I ca n’t,
For this reason, there is a danger that a serious accident may occur due to a runaway of a vehicle, an abnormal operation of a work 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 an object of the present invention is to provide a drive control apparatus for an actuated body that can automatically and early stop a work machine when a failure occurs in an electric circuit in the work machine. Things.

[Means and actions for solving the problems]

Therefore, the present invention provides 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 operation unit that calculates a control signal of the actuator in accordance with the input operation signal; and a control unit having an output unit that generates an electric drive signal in accordance with the control signal and outputs the generated signal to the actuator. A drive control device for the actuated body, comprising: an abnormality detection unit that detects an abnormality around the actuator and the output unit by monitoring a current flowing through the actuator and a control signal from the control calculation unit; Prohibiting means for prohibiting driving of the actuator in response to an abnormality detection signal of the means.

According to the invention, an abnormality around the actuator and the output section is detected by monitoring a current flowing through the actuator and a control signal from the control operation section, and when the abnormality is detected, driving of the actuator is prohibited.
As a result, when an abnormality occurs around the actuator and the output section, the operated body stops immediately.

Further, in the present invention, a command input device having an operation lever and output means for generating an operation signal according to the operation amount of the operation lever, an actuator for driving an actuated body, and an operation signal of the command input device are input. A control operation unit that calculates a control signal of the actuator in accordance with the input operation signal; and a control unit having an output unit that generates an electric drive signal in accordance with the control signal and outputs the generated signal to the actuator. In the drive control device for an actuated body provided, an abnormality detection means for detecting an abnormality of the control operation unit by monitoring a monitoring pulse signal output from the control operation unit, and an abnormality detection signal of the abnormality detection unit Prohibiting means for prohibiting driving of the actuator.

According to this invention, the abnormality of the control operation unit is detected by monitoring the monitoring pulse signal output from the control operation unit, and when the abnormality is detected, the driving of the actuator is prohibited. As a result, when an abnormality occurs in the control calculation unit, the operated body stops immediately.

Further, in the present invention, a command input device having an operation lever and output means for generating an operation signal according to the operation amount of the operation lever, an actuator for driving an actuated body, and an operation signal of the command input device are input. A control operation unit that calculates a control signal of the actuator in accordance with the input operation signal; and a control unit having an output unit that generates an electric drive signal in accordance with the control signal and outputs the generated signal to the actuator. A drive control device for an actuated body comprising: at least one of the command input device, the control operation unit, the actuator, and the periphery of the output unit.
Abnormality detecting means for detecting the two abnormalities; prohibiting means for prohibiting driving of the actuator by interrupting signal transmission between the control operation unit and the actuator by an abnormality detection signal of the abnormality detecting means. It is equipped with.

According to the invention, when the abnormality detection unit detects any abnormality in the command input device, the control calculation unit, and the actuator and around the output unit, the prohibition unit includes the control calculation unit and the actuator. By interrupting the transmission of the signal between them, the driving 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 corresponding to an operation amount of the operation lever, an actuator for driving an actuated body, and an operation signal of the command input device are input. And a control means for generating an electric drive signal for driving the actuator in accordance with the input operation signal. A neutral position detection for detecting a neutral position of the operation lever. Means, a delay means for delaying a neutral detection signal from the neutral position detecting means, and a prohibition for inhibiting transmission of a signal between the control means and the actuator by a neutral detection signal transmitted through the delay means. Means.

According to this invention, when the operator detects a machine runaway or the like, the operator sets the operation lever to neutral (neutral), the operation is detected by the neutral position detecting means, and as a result, the control means is controlled by the prohibiting means. Transmission of a signal between the actuator and the actuator is prohibited, and the operated body is emergency stopped.

Further, in the present invention, a command input device having an operation lever and output means for generating an operation signal according to the operation amount of the operation lever, an actuator for driving an actuated body, and an operation signal of the command input device are input. A control operation unit that calculates a control signal of the actuator in accordance with the input operation signal; and a control unit having an output unit that generates an electric drive signal in accordance with the control signal and outputs the generated signal to the actuator. A drive control device for the actuated body comprising: a neutral position detecting means for detecting a neutral position of the operation lever; a signal detecting means for detecting the presence or absence of an output signal from the control means to the actuator; Means and a failure diagnosis unit for determining a failure when the neutral position and the output signal are simultaneously detected by the signal detection means. It is.

According to this invention, when an output signal from the control means to the actuator is detected when the operation lever is detected to be neutral, this is diagnosed as a failure, so that the operation lever is neutralized. It is possible to avoid an unexpected situation due to a failure of each part such as an actuator being driven at a certain time.

Further, in 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 of the command input device are input. A control operation unit that calculates a control signal of the actuator in accordance with the input operation signal; and a control unit having an output unit that generates an electric drive signal in accordance with the control signal and outputs the generated signal to the actuator. A drive control device for the actuated body comprising: a neutral position detecting means for detecting a neutral position of the operating lever; a delay means for delaying a neutral detection signal from the neutral position detecting means; and Signal detection means for detecting the presence or absence of the output signal of the first position, neutral position detection means transmitted via the delay means, and the signal detection means. The neutral position and the output signal at the same time so that comprises a fault diagnosis unit for diagnosing a failure when detected by.

According to this invention, when the output signal from the control means to the actuator is detected when the operation lever is detected to be neutral based on the neutral position detection signal transmitted via the delay means, Is diagnosed as a failure.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to the embodiments shown in the accompanying drawings.

FIG. 1 shows an example of a circuit configuration of an electronic control unit for a construction machine. The electronic control unit drives and controls a plurality of electric actuators 1-1,..., 1-n. The electric actuators 1-1,..., 1-n represent, for example, solenoids. By operating these solenoids, the direction and flow rate of the flow path of a solenoid valve (not shown) can be changed. The hydraulic cylinder (not shown) is driven to expand and contract by operating these solenoid valves, and as a result, work machines such as buckets, booms, blades, upper revolving superstructures, and traveling motors as driven bodies are driven. In this case, the electric actuators 1-1 and 1-2 drive the boom up and down, respectively, and use the command input device 2-
Suppose that it is operated by 1.

A plurality of command input devices 2-1,..., 2-m for generating command signals for these electric actuators 1-1,.
(M <n) is composed of an operation lever 3, a potentiometer 4 and a neutral sensor 5, respectively. The potentiometer 4 generates voltage signals VI ₁ , VI ₂ ,..., VI _m corresponding to the displacement of the operation lever 3, and outputs them to the control calculation unit 9. The neutral sensor 5 is constituted by a cam 6 having a concave portion, a driven member 7, an electric contact 8 and the like which rotates in accordance with the displacement of the operation lever 3, and detects the neutral state of the operation lever 3 by a mechanical configuration of these. logic value when the neutral "1", the neutral signal NS _1, NS ₂ becomes logic value "0" when other than neutral, ..., and outputs the NS _m. These command input device 2-1, ..., 2-m instruction signals VI ₁ output from, ..., VI _m and neutral signal NS _1, ..., NS _m is inputted to the control arithmetic unit 9. In addition, the neutral signal
NS ₁ ~NS _m is inputted to each of the delay circuits 13-1 to 13-m, wherein after the delay processing of each predetermined time is added, the signal ND ₁
To ND _m as a control arithmetic unit 9 and a NOR gate 10-1 provided for each electric actuator, ..., it is input to 10-n.

.., 1-n based on the command signals VI ₁ ,..., VI _m input from the potentiometers 4,. the actuator drive command signal VO ₁ for driving, ..., in addition to the operation of calculating the VO _n outputs, perform work machine stop control when the abnormality diagnosis and the abnormality of the circuit portion. At this time, the control operation unit 9
When the operating lever 3 is displaced from the neutral position to the working machine driving position, the working machine operates with good responsiveness, and when the operating lever 3 is displaced from the working machine driving side to the neutral position, the working machine slowly operates. In this way, the command signals VI ₁ ,..., VI _m input from each potentiometer 3 are given a predetermined delay, and the drive signals VO _{1 to} VO _n are output based on the delayed command signals. I have to. Further, the neutral detection in the control calculation unit 9 is performed using both the command signals VI _{1 to} VI _m input from the potentiometer 3 and the detection signal of the neutral sensor 5. Are also provided on the neutral sensor 5 side so as to correspond to the command signals VI ₁ ,. Also,
When abnormality detection process in the control calculation section 9 in response to an instruction signal VI with two kinds of signals of the non-delayed and delayed, neutral signal even those that have been delayed with NS ₁ ~ns _m shall not be delayed ND
_{Both 1 to} ND _m are used. Incidentally, a deviation signal between the drive signal VO ₁ ~VO _n is for example the command signal VI ₁ to VI _m and a feedback signal outputted from the control operation unit 9 (not shown).

These drive signals VO ₁ ,..., VO _n are connected to switch circuits 11-1,.
, 12-n via 1-n, and are amplified by the amplifiers and then applied to the electric actuators 1-1,..., 1-n.

These electric actuators 1-1, ..., 1-n power supply against takes place via a power supply line 20l ₁ ~20l _3. The power line 20l ₁ ~20l ₃ is connected to the vehicle battery (not shown). This is the power line 20l ₁ ~20l ₃ is provided with a manual switch 14 and the relay 15 is enabled to shut off the power by these double structure. The power supply line is provided with a relay (not shown) on the battery side, which is described in connection with the conventional apparatus. This relay operates so as to cut off the power supply line when the diesel engine is stopped. Whether the power is turned off by the manual switch 14 is detected by the detection circuit 16 and the detection circuit
Reference numeral 16 inputs to the control calculation unit 9 a lever lock signal LR which becomes a logical value "1" when the manual switch 14 is not turned on (power supply is turned on) and a logical value "0" when the manual switch 14 is turned on (power is turned off). I do. The relay 15 is interrupted by the output signal of the NOR gate 16. When the output of the NOR gate 16 is a logical value "0", the contact is turned off. When the output of the NOR gate 16 is a logical value "1", the contact is turned off. Turn on.

For the NOR gate 16, a relay cutoff signal RE from the control / operation unit 9 and an operation unit abnormal signal from the operation unit monitoring circuit 17 are output.
When WDE is input and the NOR gate 16 has one of these signals RE and WDE at a logical value "1", the output signal thereof becomes "0" and the relay 15 is turned off (turned 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 and cut off the power supply due to some abnormality.

The arithmetic unit monitoring circuit 17 monitors an abnormality of the control arithmetic unit 9, and receives the monitoring pulse signal WD from the control arithmetic unit 9. In this case, the control operation unit 9 outputs one pulse to the operation unit monitoring circuit 17 each time the processing program for diagnosis and abnormality detection is performed in order. It is determined whether or not the arithmetic unit monitoring circuit 17 is abnormal based on whether or not the pulse cycle of the use pulse signal WD is within a predetermined range. That is, when the cycle of the monitoring pulse signal WD input from the arithmetic control unit 9 deviates from a preset predetermined range, the arithmetic unit monitoring circuit 17 determines that the arithmetic control unit 9 is abnormal. Operation unit error signal WDE with logical value "1"
Is output. Further, the abnormality of the relay 15, and inputs the voltage signal Vp of the power supply line 20l ₃ after via the relay 15 to the control arithmetic unit 9, the voltage Vp control calculation unit 9 is detected by monitoring.

The NOR gates 10-1,..., 10-n provided for the respective electric actuators are connected to switch circuits 11-1,.
The switch circuit 11 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” to the amplifier 12, and the output of the NOR gate 10 has the logical value “0”. At that time, the contact is switched so as to disconnect the output line VO. However, zero voltage is applied to the amplifier in the disconnected state. These NOR gates 10-1, ..., the 10-n, the actuator stop signal DF _1, DF ₂ from the calculating unit abnormality signal WDE and the arithmetic control unit 9 from the arithmetic unit monitoring circuit 17, ..., the the DF _n neutral Neutral signals ND _{1 to} ND _m from the sensor 5 are respectively input. The actuator stop signals DF ₁ ,..., DF _n are output from the arithmetic and control unit 9 when it is necessary to forcibly disconnect the output lines VO _{1 to} VO _m and stop the work machine due to some abnormality.

Each of the electric actuators 1-1,..., 1-n has a current detector 18-1, which detects a current value flowing through these actuators.
,..., 18-n are provided respectively, and the detected values V converted by the respective current detecting devices by 18-1,.
F ₁ ,..., VF _n are input to the control operation unit 9. Reference numeral 30 denotes an alarm device that alerts an operator of a device abnormality using a display or a buzzer.

That is, in this embodiment, as a configuration for emergency stop of the working machine, switch circuits 11-1,..., 11-n for forcibly disconnecting the command voltage / pressure line, and an automatic intermittent relay 15 for shutting off the power supply. And a manual switch 14 for turning off the power by an operator's operation.

 Hereinafter, the operation of the above configuration will be described.

The control operation unit 9 includes five types of flag signals LERF _j , RERF, A
It has ERF _i , INHF _i and OEN _j , and relays based on these flag signals, neutral signals NS _{1 to} NS _m , their delay signals ND _{1 to} ND _m , lever lock signal LR, current detection signals VF _{1 to} VF _n, etc. controlling the output of the blocking signal RE and the actuator stop signal DF ₁ ~DF _n. The flag signal LERF _j (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. When the relay 15 is abnormal, the flag signal RERF becomes "1". Flag signal AERF _{i (i} = 1~n) is an electric actuator unit 1-i, shows amplifier 12-i, and the abnormal portion of the current detector 18-i, etc., the flag signal is also n number of the electric actuator Are provided separately for each. While flag signal INHF _i shows a abnormality of RERF same relay 15, if the flag INHF _i becomes "1", by sending all of the actuators stop signal DF ₁ ~DF _n, the drive signal VO so as to cut off the supply of _{1 ~VO n,} from both sides of the blocking of the blocking and driving signals VO ₁ ~VO _n power to stop the actuator, and to improve the fail-safe property. The flag signal OEN _j serves as a "1" when the operation lever portion corresponding fails, the actuator stop signal DF _i corresponding case where the control in the computing unit 9 is the flag signal becomes "1" Output as "1".

The control operation unit 9 outputs these flag signals and signals ND _{1 to} ND _m ,
Using a lever lock signal LR, it outputs a relay-off signal RE and the actuator stop signal DF ₁ ~DF _n according to the following formula.

RE = ▲ ▼ + RERF (1) DF _i = ND _j + AERF _i + INHF _i + OEN _j (2) FIG. 2 shows an example of an abnormality detection processing procedure of the control arithmetic unit 9, and refer to this flowchart below. The operation of the control operation unit 9 will be described. This flowchart is
It is roughly divided into three parts: failure diagnosis of the operating lever, failure diagnosis of the relay, and failure diagnosis around the amplifier.

Control calculation unit 9 prior to the abnormality detection processing, the aforementioned flag signals _{LERF j, RERF, AERF i,} OEN j, and performs relay-off signal RE, the actuator stop signal DF ₁ ~DF initialization such as _n (step 100). In this initialization,
Each flag signal is "0", the signal RE and DF ₁ ~DF _n is initialized on the work vehicle stop side, i.e., "1".

-Diagnosis of failure of operation lever First, the control calculation unit 9 performs failure diagnosis of the command input device 2, that is, the operation lever unit.

The command input devices 2-1,..., 2-m are a half-duplex system as described above.
Command signal VI _{j (j} = 1~m) a neutral signal NS _j from the neutral sensor 5 (j = 1~m) are respectively inputted, the control arithmetic unit 9, based on these input signals control lever from Is determined. That is, as shown in FIG. 3, the control arithmetic unit 9 determines three different set values V ₁ , V ₂ and V ₃ (V ₂ <V ₁ <V
₃₎ is set as the value of s positive and negative respectively, the control operation unit 9 uses these set values V ₁ ~V _3, first the failure diagnosis for command input device of j = 1 (step 110).

Control calculation section 9 as compared with the command value V ₃ at full stroke of the operating lever 3 the absolute value of the command signal VI ₁ input from the potentiometer 4 (step 120), | VI ₁ | is> when V ₃ e.g. It determines that failure due to disconnection or Ciro lever harness, and a flag signal LERF _{1 "1"} (step 130).
When | VI ₁ | ≦ V ₃ , the control calculation unit 9 sets the command signal VI ₁ to V ₂ <when the neutral signal NS ₁ switches from “1” to “0” or from “0” to “1”. When VI ₁ <V ₁ is not satisfied, it is determined that the operation lever is broken due to a displacement of the potentiometer or the like. That is, the control calculation unit 9 determines “0” and “1” of the neutral signal NS ₁ (step 140), and when the signal NS ₁ is “0”, compares the command signal VI ₁ with the set value V _2. (Step 150), when the comparison result is | VI ₁ | ≦ V ₂ , it is determined that the operation lever is faulty and the flag signal LERF _{1 is set} to “1” (Step 130), and when | VI ₁ |> V ₂ Is determined to be normal. Control calculation unit 9 when the neutral signal NS ₁ is "1" in the judgment of step 140 is a command signal VI ₁ setpoint V ₁ a
Compared (step 160), the comparison result is | VI ₁ | when the ≧ V ₁ and "1" is determined by flag signal LERF ₁ and failure of the operation lever (step 130), also | VI ₁ | <V _If it is ₁ , it is determined to be normal. When the flag signal LERF ₁ by the fault diagnosis has become "1", the control calculation unit 9 thereafter driving signal VO ₁ a command signal VI ₁ inputted from the instruction input device as neutral i.e. zero regardless of the input value ... performs internal processing of the output control of the flag signal OEN ₁ to "1" (step 170). When the flag signal OEN ₁ becomes "1", the command input device actuator stop signal corresponding to (in this case 2-1) (in this case DF ₁ and DF ₂₎ is "1" in the subsequent step 380, the As a result, each contact of the switch circuits 11-1 and 11-2 is switched to the zero voltage side,
The drive signal supplied to each of the amplifiers 12-1 and 12-2 becomes zero, and the corresponding electric actuators 1-1 and 1-2 are deenergized.

Hereinafter, the control operation unit 9 performs the same failure diagnosis on the command input devices of j = _{2 to m,} and when an abnormality is detected, sets the flag signals LERF _{2 to} LERF _m to “1” and sets the command determined to be abnormal. By deactivating the drive signal output line related to the input device, the corresponding electric actuator is deenergized (Step 180, Step 190, Step 110, ...).

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

First, in step 200, the flag signals INHF _{1 to} INHF _n
Is initialized.

Next, the control calculation unit 9 sets “0”, “1” of the relay cutoff signal RE.
Is determined (step 210). This signal RE is “1” in the initial state, and the connection of the manual switch 14 (power line connection)
When the flag signal RERF is set to "1", the power supply line is connected again. When the flag signal RERF is set to "1", the power supply line is cut off again. (See step 380). If the signal RE is “1” in the determination of step 210, the control operation unit 9
determining a voltage value Vp of l ₃ (step 220), the voltage value Vp
Is zero or a value close to zero, it is determined that the power cutoff relay 15 is normal, and then the flag signals INHF _{1 to} IHF
NHF _n is all set to "1" (step 250). As a result, in step 380, all the actuator stop signals DF ₁ to
DF _n is output as "1", thereby the contacts of all the switch circuits 11-1 to 11-n is switched to zero voltage side drive signal VO ₁ ~VO _n of the control arithmetic unit 9 the electric It is no longer supplied to the actuators 1-1 to 1-n. Step 22
If it is determined at 0 that the voltage value Vp 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. This condition, a power cutoff relay 15 is in a state in which the cross-sectional and despite that the voltage on the power supply line 20l ₃ occurs, high risk. For this reason, the control operation unit 9 is provided with the alarm device 30
To notify the operator of the abnormality. In response to this abnormality report, the operator turns on the manual switch 14, cuts off the power supplied to each of the electric actuators 1-1 to 1-n, and can stop the work machine in an emergency. In this case, the flag signal INHF ₁ ~INHF _n is similarly "1", the result, the actuator stop signal DF ₁ ~DF _n is output at step 380, to each electric actuator 1-1 to 1-n is in a state in which the driving signal VO ₁ ~VO _n is not supplied.

In the determination at step 210, the relay cutoff signal R
If E is "0", the control operation unit 9 determines the voltage value Vp of the power supply line 20l ₃ is whether is greater than the predetermined set voltage value Vc (Step 230). If Vp ≦ Vc in this determination, the control calculation unit 9 determines that a relay operation failure has occurred, and turns on the flag signals RERF and INHF _{1 to} INHF _n (step 240, step 250). By lighting these flags,
Thereafter, the power cutoff relay 15 is turned off, and the switch circuits 11-1 to 11-n are switched to the zero voltage side. The steps
In the determination at 210, if Vp> Vc, the relay 15 is determined to be normal, and the procedure shifts to the next processing, that is, the abnormality determination processing of the electric circuit around the electric actuator 1-i.

-Diagnosis of failure around amplifier First, the control operation unit 9 determines the electric actuator 1, the switch circuit 11, the amplifier 12, and the current detector 18 for i = 1.
Is determined (step 260).

In this failure determination to determine "0", "1" of the control calculation unit 9 first actuator stop signal DF _1. If the signal DF ₁ is “1” in this determination, the current detector 1
Determining a detection value VF ₁ 8-1 (step 280), when VF ₁ has a value close to zero is determined to be normal, and shifts the procedure to the process of the i = 2 (step 350). Also step 2
In the judgment of 80, if VF ₁ is not a value near zero,
For example short circuit of the short-circuit or amplifier 12-1 with the solenoid drive harness and the power line is considered, the control calculation unit 9 a flag signal AERF ₁ to "1" (step 290), a further flag signals RERF "1" (Step 300). As a result,
In step 380, the drive signal output lines of the actuator 1-1 is disconnector with relay interrupting signal RE and the actuator stop signal DF ₁ both "1", the relay 15 is turned off.

Further, the control arithmetic unit 9 in the case of the signal DF ₁ is "0" in the judgment at the step 270 with reference to the driving signals VO ₁ and the current detection value VF ₁ at the present time, the drive signal VO _i and current shown in FIG. 4 performing an abnormality determination from the relationship between the detection value VF _i. In FIG. 4, a straight line VF _i −VO _i = V _tH and a straight line VO _i −VF _i
= V _tL and divided into three regions I, II, and III. The control calculation unit 9 determines which of the three regions the current state belongs to, and for each of the determined regions, Perform another process.

That is, by the determination in step 310, it is determined whether the region III or the other region. In the case of the region III, disconnection and ground fault of the solenoid drive harness are considered, but generally, in this case, the determination of the cause of the failure is ambiguous. since, the control calculation unit 9 to both "1" to the flag signal AERF ₁ and RERF (step 290, 300). As a result, the relay 15 is turned off, and the drive signal supplied to the actuator 1-1 is cut off.

If the determination in step 310 is "NO", it is next determined whether the region is I or II (step 320). If it is determined that the area is II, these device parts are determined to be normal, and the procedure shifts to the processing for i = 2 (step
350). If it is determined that the region III is determined, a failure such as a chute of the solenoid drive harness is considered. In this case, the control calculation unit 9 sets the flag signal AERF ₁ to “1” (step 330) and sets a portion around the failed amplifier. performing subsequent internal processing as neutral irrespective command signals VI ₁ that is input to the input value from the electric actuator to be driven (in this case 1-1) corresponding command input device (in this case 2-1) by ( Step 340). In this case, since the flag signal AERF ₁ becomes “1”, the subsequent step 380
, The actuator stop signal DF ₁ becomes “1”, and as a result, the drive signal VO ₁ supplied to the actuator 1-1
Is refused. In this case, the processing procedure of the control operation unit 9 returns from step 380 and the processing from step 110 is repeated again.
Since the determination of 270 is YES, then the current detection value VF _i is checked (step 280). At the time of the determination in step 280,
Thereafter error flag if the current detection value VF ₁ is a value close to zero is not turned on (step 350 ...). However, current detection value VF ₁ in the determination of step 280 and if not, the value of close to zero then the flag signal RERF is illuminated (step
290,300). That is, when a failure occurs in the region I, the actuator stop signal (in this case,
DF ₁ ) is output to demagnetize only the electric actuator (1-1 in this case). Thereafter, the value of the current flowing through the electric actuator is checked. The output of only this electric actuator is stopped, and a drive signal is supplied to the other electric actuators. However, if the current value at the time of the check is not a value near zero, the relay cutoff signal RE indicates that the relay
Turn off 15 and cut off the power supply to all electric actuators.

Hereinafter, the control operation unit 9 performs the same failure diagnosis on the parts around the amplifiers where i = 2 to n (steps 350 and 36).
0,270,…). Then, the control calculation unit 9 is configured to control each command input device 2
Drive signal to the electric actuator 1-1 to 1-n based on the command signal VI ₁ to VI _m input from -1 to 2-m
Calculating a VO ₁ ~VO _n, and outputs. At this time, the command signal determined to stop the command by the failure diagnosis described above is handled as neutral, that is, zero, as described above.

Finally control calculation section 9 (1) and (2) a relay-off signal RE and the actuator stop signal DF _i and logical operation in accordance with the logical expression shown in expression, and outputs the calculation results (step 180). Such control is repeatedly executed while the work machine is driven.

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

(1) The failure detection of the command input device 2 is performed by the control operation unit 9 monitoring the command signal VI and the neutral signals NS and ND, and outputs a corresponding actuator stop signal DF when a failure occurs. The output line of the actuator drive signal VO relating to the failed command input device 2 is forcibly cut off to demagnetize the corresponding electric actuator.
Incidentally, the command input unit 2 so neutral signal ND ₁ to ND _m is directly input to the NOR gate 10-1 to 10-n in this configuration, the operation unit 9, the arithmetic unit monitoring circuit 17, a NOR gate
Even when at least one of the relay 16 and the relay 15 has failed, if the operator performs an operation of returning the operation lever to the neutral position, the work implement associated with the operated operation lever can be emergency stopped.

(2) When the control operation unit 9 fails, the operation unit monitoring circuit
17 detects this and turns off the power cutoff relay 15 by the signal WDE. As a result, each work machine is completely stopped. With the failure of the control operation unit 9, the NOR gate 16 or the relay 15
In the case of a double failure, if the operator returns the respective operating levers to the neutral position as described above, the working machine can be stopped as long as the NOR gate 10 and the amplifier 12 are normal.

(3) The failure detection of the NOR gate 10, the amplifier 12, the electric actuator 1, and the current detector 18 is performed by detecting the current detection value VF.
This is performed by monitoring the control signal 9 and the drive signal VO (see FIG. 4). In the event of a failure in the region I in FIG. 4, the control operation unit 9 outputs a corresponding actuator stop signal DF to forcibly cut off the output line of the drive signal VO relating to the failed amplifier 12 and the like. Demagnetize only the electrically operated actuator. If the current detection value VF flowing through the electric actuator becomes an appropriate value near zero due to the demagnetization, this state is maintained to stop only the output for the working machine related to the failed part. However, if the current detection value VF does not become zero due to the demagnetization, the control operation unit 9 outputs the relay cutoff signal RE to cut off the power supply and stop all the working machines.

Further, when a failure occurs in the region III, the determination of the failure state is ambiguous, so the control operation unit 9 outputs the relay cutoff signal RE to cut off the power supply and stop all the working machines.

(4) When the power-off relay 15 is in a state where the power-off relay 15 is shut off, the work equipment does not operate, so it is a safety-side failure.
In this case, the control operation unit 9 does not perform any special processing. If a failure occurs while the relay 15 remains conductive due to the failure of the NOR gate 16 or the power cutoff relay 15 itself,
Normally, this cannot be determined by the control calculation unit 9.
However, in this case, the control operation unit 9 can determine when a simultaneous failure occurs with another component, for example, the NOR gate 10 and the amplifier 12. That is, the NOR gate 10 and the amplifier
When the power supply 12 is out of order, a relay cutoff signal RE for turning off the power cutoff relay 15 is output from the control calculation unit 9. At this time, the voltage VP on the output side of the relay 15 is monitored. The unit 9 can detect an abnormality of the relay 15 or the NOR gate 16. In this case, the control operation unit 9 notifies the operator by operating the alarm device 30.
If the operator turns off the manual switch 14 in response to the notification, the work machine is completely stopped.

In such a case, if the operator feels any abnormality from the operation of the machine, the operator can shut down the manual switch 14 to immediately stop the work machine.

(5) Potentiometer 4 and neutral switch 5
The simultaneous double failure of the amplifier 12 and the simultaneous double failure of the amplifier 12 and the current detector 18 occurs only with a very small probability. In this case, the operator determines that the manual switch 14 Should be cut off.

In the above embodiment, the logical form and the signal connection form are made to have a certain degree of redundancy in consideration of the fail-safe property. Of course.

〔The invention's effect〕

As described above, according to the present invention, an abnormality around the actuator and the output unit is detected by monitoring a current flowing through the actuator and a control signal from the control operation unit. Since the driving is prohibited, even when an abnormality occurs around the actuator and the output section, the driven body can be automatically stopped at an early stage. Accidents can be prevented beforehand.

Further, in the present invention, the abnormality of the control operation unit is detected by monitoring the monitoring pulse signal output from the control operation unit, and when the abnormality is detected, the driving of the actuator is prohibited. Even when an abnormality occurs in the section, the operated body can be automatically stopped early, and as a result, a serious accident due to a runaway vehicle, an abnormal operation of the operated body, and the like can be prevented.

Further, in the present invention, a prohibiting means for prohibiting driving of the actuator by cutting off signal transmission between the control calculation unit and the actuator is provided, and the prohibiting means is provided with a command input device, a control calculation unit, an actuator and Since the operation is performed in accordance with the diagnosis result about the output section, the actuated body can be automatically stopped early,
As a result, it is possible to prevent a serious accident due to runaway of the vehicle, abnormal operation of the operated body, and the like.

Further, according to the present invention, the prohibition means for prohibiting the transmission of the signal between the control means and the actuator is provided, and the prohibition means is operated based on the neutral detection, so that even when an abnormality occurs in each part of the apparatus. By setting the operation lever to neutral, the operated body can be quickly decelerated or stopped.

Further, in the present invention, when the output signal from the control means to the actuator is detected when the operation lever is detected to be neutral, this is diagnosed as a failure, so that the operation lever becomes neutral. It is possible to reliably prevent an unexpected situation due to a failure of each part such as driving of the actuator at a certain time.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram showing one embodiment of the present invention, FIG. 2 is a flowchart showing a specific operation example of a control operation unit of this embodiment device, and FIG. 3 explains an abnormality detection process of a command input device. FIG. 4 is a diagram for explaining an abnormality detection process for a portion such as an amplifier. 1 ... electric actuator, 2 ... command input device, 3 ...
... operating lever, 4 ... potentiometer, 5 ... neutral sensor, 6 ... cam, 7 ... moved object, 8 ... electric contact, 9 ... control operation unit, 10,16 ... NOR gate, 11 ...
... Switch circuit, 12 ... Amplifier, 13 ... Delay circuit, 14 ...
… Manual switch, 15… Relay, 17… Operation unit monitoring circuit, 18… Current detector, 20l _{1 to} 20l ₃ … Power supply line, 30
…… A warning device.

Claims (6)

(57) [Claims] 1. 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 being input. A control operation 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 generated signal to the actuator; 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 monitoring a current flowing through the actuator and a control signal from the control calculation unit; Prohibiting means for prohibiting the driving of the actuator by an abnormality detection signal of the detecting means. Drive control device of the actuating member. 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 being input. A control operation 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 generated signal to the actuator; An abnormality detection means for detecting an abnormality of the control operation section by monitoring a monitoring pulse signal output from the control operation section, and an abnormality detection signal of the abnormality detection section. And a prohibiting means for prohibiting the driving of the actuator by means of: a drive control device for the actuated body. 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 being input. A control operation 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 generated signal to the actuator; A drive control device for an actuated body, comprising: a command input device, the control calculation unit, and an abnormality detection unit that detects at least one abnormality among the actuator and the periphery of the output unit; The transmission of the signal between the control operation unit and the actuator is interrupted by an abnormality detection signal of the means. Drive control device of the actuating member, characterized in that it comprises a prohibiting means for prohibiting the driving of the over motor, the. 4. 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 object to be actuated, and an operation signal of the command input device being input. And a control means for generating an electric drive signal for driving the actuator in accordance with the input operation signal. A drive control device for an actuated body, comprising: a neutral position detection means for detecting a neutral position of the operation lever. Delay means for delaying a neutral detection signal from the neutral position detecting means; and prohibiting means for inhibiting transmission of a signal between the control means and the actuator by a neutral detection signal transmitted through the delay means. A drive control device for an actuated body, characterized by comprising: 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 being input. A control operation unit that calculates a control signal of the actuator in accordance with the input operation signal; and a control unit having an output unit that generates an electric drive signal in accordance with the control signal and outputs the generated signal to the actuator. A drive control device for an actuated body comprising: a neutral position detecting means for detecting a neutral position of the operation lever; a signal detecting means for detecting the presence or absence of an output signal from the control means to the actuator; and a neutral position detection. Means and a failure diagnosis unit that determines that a failure has occurred when the neutral position and the output signal are simultaneously detected by the signal detection means. A drive control device for an actuated body, characterized in that: 6. 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 being input. A control operation unit that calculates a control signal of the actuator in accordance with the input operation signal; and a control unit having an output unit that generates an electric drive signal in accordance with the control signal and outputs the generated signal to the actuator. A drive control device for an actuated body comprising: a neutral position detecting means for detecting a neutral position of the operating lever; a delay means for delaying a neutral detection signal from the neutral position detecting means; and Signal detection means for detecting the presence / absence of an output signal, and neutral position detection means transmitted through the delay means and the signal detection means. And a failure diagnosis unit that diagnoses a failure when the neutral position and the output signal are detected at the same time.