JPH0656802U - Output diagnostic device for controller - Google Patents

Abstract

(57) [Abstract] [Purpose] In a failure diagnostic device for self-diagnosing a failure of an output system connected to a microprocessor unit MPU, when a check signal is output to each actuator for diagnosis. , Prevents unexpected operation of each actuator. [Configuration] The output time t of the check signal output to each actuator 25, 26, 27 is set to an output time shorter than the minimum operable output time T of each actuator,
The output system is diagnosed without substantially operating each actuator.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a failure diagnostic device for a control device, and more particularly, to an output diagnostic device capable of immediately diagnosing an abnormality of an actuator connected to a control unit without using a special tool.

[0002]

[Prior art]

 A work vehicle such as a tractor and a combine is equipped with a control device for controlling each part of the work machine and the vehicle. The control unit which is the center of the control device has a one-chip type MPU (microprocessor unit). ) Is generally adopted. However, if the MPU forming this control unit fails, various automatic controls and manual controls become impossible, and in the worst case, there is a problem that the work must be interrupted and repaired. Even if the MPU itself does not break down, the same problem occurs even if the actuator drive circuit connected to the MPU or the actuator itself malfunctions. For this reason, it is desirable to find out the failure of the control device as soon as possible so that it can be appropriately dealt with, and for the failure of the control unit, the self-diagnosis of this by the control unit itself before the work is notified to the outside. The measures such as doing are taken. However, in control devices installed in work vehicles, there are more failures due to actuators such as motors and solenoids than failures in the control unit.For example, actuator damage, actuator connection failure, Examples include disconnection and short circuit.

However, such a failure of the output system connected to the control unit cannot be detected without a tester or a special checker, and the content of the failure is simple. However, there was a problem that the user could not deal with it and asked the dealer to repair it, and it took a long time to repair it, making it difficult to recover quickly. Therefore, the present inventor has already proposed a failure diagnosis device described in Japanese Utility Model Application Laid-Open No. 2-81108 as a device capable of immediately diagnosing a failure of an output system connected to a control unit without requiring a special tool. It is applied to the control device of. Prior to this, JP-A-56-57102 proposes a method for diagnosing whether the control output is normal or abnormal at the start of the automatic control operation and displaying it to improve safety.

[0004]

[Problems to be solved by the device]

 However, the failure diagnosis device according to the present inventor actually outputs a check signal to each actuator to diagnose the failure of the output system. Therefore, if a check signal is output to each actuator for a predetermined time or longer, each actuator will actually operate, as in the case of normal control.For example, if there are people around, the work equipment will suddenly descend and cause harm. There was a fear of giving. In addition, some actuators may be equipped with a mechanical locking device to prevent accidental operation.In such a case, you must remove the locking device in advance and then perform failure diagnosis. As a result of the lock device blocking the operation of the actuator, there was a problem that the fuse provided in the circuit was blown by the lock current. For this reason, when performing a failure diagnosis, it must be checked in advance whether there are any people around and whether or not the actuator locking device is disengaged, which is cumbersome and leaves room for improvement. Also, the latter diagnostic device automatically checks the status of each control output by disconnecting the actuator from the control unit by a relay prior to the start of automatic control. Therefore, although the above-mentioned problems and annoyances do not occur, this diagnostic device originally diagnoses only the presence or absence of the control output from the control unit in order to avoid the danger at the beginning of the automatic control. Therefore, there is a problem that it cannot be applied to an output system failure diagnosis device that checks all output systems including actuators, which is the object of the present invention.

[0005]

[Means for Solving the Problems]

 Therefore, the purpose of the present invention is to re-verify the failure diagnosis device devised by itself and to eliminate the problem, and in particular to the signal output means of the output diagnosis device for outputting the check signal, the actuator output of each actuator. By providing time setting means for allocating an output time shorter than the minimum operable output time, the output system can be diagnosed without substantially operating each actuator.

[0006]

[Action]

 When diagnosing the output of the control device, the mode selection means changes the control unit from the normal control mode to the check mode. As a result, the control unit changes the control content from the normal control software to the output check software, and the signal output means of the control unit outputs the check signal to each actuator. Then, the operation command signal actually transmitted to each actuator based on the check signal is fed back to the control section by the signal input means, whereby the abnormality is judged and the abnormality notification means notifies the result to the outside. To do. In this case, the presence or absence of abnormality is determined by whether or not the operation command signal has changed before and after the check signal is output to each actuator. It is notified to the outside. Further, during this output diagnosis, the time setting means allocates an output time shorter than the signal time at which each actuator can be operated at the minimum. Therefore, the signal output means outputs the check signal to each actuator only for a short time set by the time setting means. Therefore, the actuator command signal is cut off before the actuators actually operate, and the actuators do not substantially operate.

[0007]

【Example】

 Next, an embodiment of the present invention will be described with reference to the drawings. In FIG. 1, a combine 1 has a pretreatment device 4 mounted vertically on a front part of a machine body 3 having a crawler traveling device 2. Further, a threshing device 5 and a straw treatment device 6 are mounted on the rear body 3 respectively, and a control unit 7, a grain tank 8 and the like are mounted on the right side of the body 3 in order from the front. . Further, the grain tank 8 is provided with a grain discharging auger 9, and the grain discharging auger 9 is locked by a mechanical locking device (not shown) except when the auger is actually operated. There is. In addition, as shown in FIG. 2, the control section 7 includes an operation lever 10 for operating and operating each section of the combine, an automatic switch 11 for selecting various automatic controls, a manual operation switch 12, ... The output check switch 13, the tachometer 14, the indicator lamp 15 and other instruments are provided, and the one-chip type MPU (microprocessor unit) that constitutes the control unit is housed in the box 17 below the driver's seat 16. is doing. In addition, one MPU or a plurality of MPUs are provided as necessary to execute, for example, depth control, direction control, cutting height control, machine level control, auger automatic storage control of the combine. .

Further, FIG. 3 is a block diagram showing an outline of the control device, and the above-mentioned MPU is supplied with a voltage of 5 V from the battery 18 via the key switch 19 and the constant voltage device 20. Further, the input ports INa to INd of the MPU are connected with an automatic switch 11, a manually operated switch 12, switches 21a and 21b of various sensors, etc. via a 12V power supply and pull-up resistors r ... An output check switch 13 is similarly connected to the port IN1. Further, a signal line a is connected to the input port IN2, and the signal line a plays a role of feeding back an operation command signal of each actuator connected to the MPU to the MPU. Further, a plurality of actuators 25, 26 for controlling the operation of each part of the combine are connected to the output ports OUT0 to OUT3 of the MPU via a transistor circuit 22, a relay circuit 23, or a FET (field effect transistor) circuit 24. 27 are connected, and these motors 25 (for turning the grain discharge auger 9), solenoids 26, 27 (attached to the solenoid valve for switching the hydraulic cylinder for raising and lowering the pretreatment section to the ascending side and the descending side), A voltage of 12V is supplied from a power source based on an operation command of the drive circuits 22, 23 and 24 to operate. Further, the horn 28 and the lamps 29a to 29c are similarly connected to the output ports OUTa to OUTd via the FET circuit 24. The other end of the signal line a, which is connected to the input port IN2, is connected to the coupling portion that connects the actuators 25, 26, 27 and the drive circuits 23, 24 with the diode D, which is in the forward direction toward the actuator, interposed therebetween. When the actuators 25, 26, 27 are energized based on the commands of the drive circuits 22, 23, 24, the potential of the signal line a is pulled up by the 12V power source to a high level. It changes to low level.

On the other hand, FIG. 4 shows a main flow chart of the MPU. When the MPU is activated by turning on the key switch, the MPU performs an initial set, and by turning on or off the output check switch 13, normal control and output check control are performed. Select and execute each. When the normal control is selected, various automatic controls and manual controls are executed, and when the output check switch 13 is turned on by the operator, the control content shifts to the output check control. Note that the specific control contents of the normal control are well known, and therefore description thereof will be omitted. 5 and 6 show specific flow charts of the output check control, which starts by judging the rise of the output check switch 13 from OFF to ON. Then, when the output check switch 13 rises from OFF to ON, the output flag and the error flag are reset, and the check signal is output to the output port OUT0 of the MPU (n = 0). Then, the output time is set to t0 and the output flag is incremented. Furthermore, the output to the output port OUT0 continues until the end of the timing of the output time t0. When the timing ends, the check flag is reset and it is checked whether the actuator operation command signal is input to the input port IN2 of the MPU. To be If a signal is normally input to the input port IN2, the check flag is set to 1. If no signal is input and it is the same as before the check signal was output, the check flag is set to 0. , Output to all actuators is stopped.

In the next step (n = 1), the presence or absence of abnormality is determined based on the above-mentioned check flag. If the check flag is 1, the next output port OUT1 is designated and the output time t1 A check signal is output to the source. However, if the check flag is not 1, the error flag is first set to 1, and the intermittent output command is issued to the output ports OUTa and OUTb of the MPU. As a result, the horn 28 operates intermittently, the lamp 29a blinks, and the outside is informed that there is an abnormality in the output port OUT0 system. Then, similarly to the case where there is no abnormality, the output port OUT1 is designated, the check signal is output under the output time t1, and the check continues in the same manner thereafter. When the check of all actuators is completed (output flag = n), the error flag is checked, and if the error flag is still reset, the output command is issued to the output port OUTa for a predetermined time, and the output port OUTb is also output. Continuous output commands are issued to ~ OUTd. Therefore, the horn 28 is operated for a short time, all the lamps 29a to 29c are maintained in the continuous lighting state, and it is notified that all the actuators have no abnormality. If the error flag is set, the previous state is maintained and the horn 28 continues to blink intermittently and the lamp corresponding to the abnormal portion continues to blink. This is shown in a time chart of FIG. 7, in which the solid line state indicates that everything is normal, and the broken line state indicates, for example, that the x point of the relay circuit 23 is broken and the output is This shows the case where there is an abnormality in the port OUT1 system.

Further, the output times t0, t1 ... For each actuator in the described embodiment are set to values unique to each actuator 25, 26, 27, and the output time is set from the MPU to each actuator. In contrast, when the output signal is output, the value t is set to be slightly shorter than the time T (the minimum operation signal time) until the actuator actually starts operating. Also, this output time t is set to a value after the check signal is transmitted from the output port of the MPU to the drive circuit, the elements of this drive circuit are fully activated, and the output command is actually issued to the actuator. If the output time t 1 is set shorter than that, the operation command signal of each actuator based on the check signal is not properly fed back to the MPU, which is meaningless. Therefore, the output time t is set to the time between when the actuator is actually energized after the actuator is commanded to operate by the output port of the MPU and when the actuator substantially starts operation. In the case of the motor 25 shown in FIG. 1, the output times t0 and t1 are set to about 0.05 seconds, and in the case of the solenoids 26 and 27, the output times t0 and t1 are set to about 0. Set to 015 seconds. If multiple actuators connected to the MPU use the same drive circuit and the same actuator, or if all actuators have a common time zone that satisfies the above time conditions. The output time t can be set to one common output time, in which case the software configuration can be simplified.

As described above, when the output of the control device is diagnosed by the fault diagnosis device of the present invention, the control content is changed from the normal control mode to the check mode by the mode selection means (output check switch 13). Then, in the check mode, the signal output means individually outputs the check signal to each of the actuators 25, 26 and 27. Further, the signal input means (signal line a) feeds back the operation command signal of each actuator based on the check signal to the control unit (MPU), and the abnormality of the output system is judged based on the input signal. Whether or not there is an abnormality is determined by whether or not there is a change in the operation command signal of each actuator before and after the check signal is output to each actuator 25, 26, 27. If there is no change, the abnormality is judged. Then, the external notification means (28, 29a to 29c) is activated to notify that effect. If all actuators are normal, the fact is similarly notified. Therefore, the failure diagnosis of the output system connected to the control unit can be immediately performed by the control unit (MPU) itself without using a special tool. Further, during the output diagnosis, the time setting means allocates the output time t shorter than the minimum operable signal time of each actuator to the signal output means. Therefore, the signal output means outputs the check signal to each actuator only for a short time set by the time setting means, and each actuator 25, 26, 27 does not substantially operate. Therefore, the failure diagnosis can be performed without removing the lock device equipped on the grain discharging auger 9 as it is, and the fuse h provided in the circuit can be prevented from being blown by the lock current.

[0013]

[Effect of device]

 As described above, according to the present invention, the control unit for controlling the operation of a plurality of actuators based on the input signal, the mode selection means for changing the control content from the normal control mode to the check mode, and the check signal for each actuator in the check mode are provided. Signal output means, a signal input means for inputting the operation command signal of each actuator based on the check signal to the control section, and an abnormality of the output system is judged based on the input signal, and the result is notified to the outside. Since the failure diagnosing device is configured by providing an abnormality notifying unit that operates as described above, an abnormality in the output system connected to the control unit can be quickly diagnosed without requiring a special tool, and prompt and appropriate response can be taken. Can be taken. Moreover, since the above-mentioned signal output means is provided with a time setting means for allocating an output time shorter than the minimum operable output time of each actuator, each actuator is substantially operated at the time of failure diagnosis. It is possible to make a diagnosis without any trouble, and it is possible to dramatically improve safety.

[Brief description of drawings]

FIG. 1 is a perspective view of a combine.

FIG. 2 is a perspective view of a control unit.

FIG. 3 is a block circuit diagram of a control device.

FIG. 4 is a main flowchart of a control unit.

FIG. 5 is a flowchart of output check control.

FIG. 6 is a flow chart of output check control.

FIG. 7 is a time chart diagram of output check control.

[Explanation of symbols]

 MPU Microprocessor unit a Signal line t Output time 13 Output check switch 25 Motor 26 Solenoid 27 Solenoid 28 Horn

Claims (1)

[Scope of utility model registration request] 1. A control unit that controls the operation of a plurality of actuators based on an input signal, a mode selection unit that changes the control content from a normal control mode to a check mode, and outputs a check signal to each actuator during the check mode. A signal output means, a signal input means for inputting an operation command signal of each actuator based on the check signal to the control section, and an abnormality notifying means for determining an abnormality of the output system based on the input signal and notifying the result to the outside. In the failure diagnosing device, the signal output means is provided with time setting means for allocating an output time shorter than the minimum operable output time of each actuator, and each actuator is substantially operated by the time setting means. An output diagnostic device for a control device, which is characterized in that the output system is diagnosed without the need.