JPS5822402A - work machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention #i relates to working machines such as agricultural machines, construction machines, civil engineering machines, etc., and item n, which will be described in more detail, relates to working machines equipped with an automatic control device based on a microcomputer.

Combine harvesters as shown in FIG. 1 have recently been provided with various automatic control functions. That is, automatic steering, automatic steering depth adjustment, automatic speed adjustment, etc., as well as many automatic monitoring functions.

With the advancement of sensors in each building, we are aiming to perform more control.For this purpose, we have installed an automatic control device using a microcomputer to control the weight of the heavy element circuit. However, these work machines are used outdoors and have a lot of vibration, so it is difficult for microcomputers to use them. The conditions are harsh, the machine itself moves, has dangerous parts such as knives, and heavy objects are often handled, so a malfunction of the microcomputer could cause the automatic control system to run out of control, resulting in an extremely dangerous situation. The present invention was made in view of such circumstances, and
The microcomputer is configured to virtually constantly monitor its operation, and if any abnormality is detected in its operation, the microcomputer is set and the automatic control system is activated. It is an object of the present invention to provide a working machine that can avoid dangers caused by runaway operation.The working machine according to the present invention will be described in detail below with reference to the drawings showing an embodiment of a combine harvester. FIG. 2 is a circuit diagram schematically showing the main parts of the automatic control device of the machine of the present invention.

A microcomputer 10 is the control center of the automatic control device and consists of a CPU (Central Processing Unit) 11, a human output interface 12, a ROM (read-only memory) 13, a RAM (random access memory) 14, etc., and an operation column. It is stored inside the l. Increasing the cutting height of a large number of people at the turnout cutter 7 face 12) 12avcij respectively.

Switches 31゜32 that are manually operated when descending the sea bream
The mowing height increase WI+ of the hide sensor that detects the distance between the reaping part 2 and one surface for automatic mowing height adjustment, contact points 33 and 14 for lowering commands, respectively when instructing speed increase and deceleration, respectively. Switches 35 and 36 to be operated, switch 37 to be operated when stopping the engine in an emergency, and three output terminals 38a, 38b, 38c for the handling cylinder rotation speed detection circuit.
etc. are in succession.

Each input port is configured to be at the 0-level when a high-level operation signal corresponding to the potential of the battery 39, for example, is not input.
When the handling cylinder load becomes a light load state that is equal to or higher than the upper limit of the appropriate rotational speed that is judged to be normal, the output terminal 3Ela is set to 71 to instruct speed increase, and the lower limit of the appropriate rotational speed is set or lower. When a heavy load condition occurs, the output terminal 38bi is set to a high level to instruct deceleration, and when an abnormal l load condition that is lower than the lower limit value occurs, this signal is set to n'6.
In order to report, output terminal 38ck is set to high level.

- Force output baud) 1.2'bVcij Controlled system components such as actuators and lamps are connected. 41°42.
43 and 44 are various monitor lamps and alarm lamps,
For example, when the output terminal 38c of the handling cylinder rotation speed detection circuit 38 becomes high level, the lamp 41 lights up. Solenoid 45.46d is for switching control of the electromagnetic switching valve provided in the hydraulic circuit of the mower barrel height adjustment device, and is for switching control of the electromagnetic switching valve.
．． When the contact 33 is closed, the solenoid 45 is energized to raise the reaping section 2, and the switch 32. When the contact point 34 is closed, the solenoid 46 is energized to lower the reaping section 2. Solenoids 47 and 48 are used to control the switching of the electromagnetic switching valve provided in the hydraulic circuit for speed adjustment, and when the switch 35 is closed or the output terminal 38a of the detection circuit 3 becomes high level. In this case, the solenoid 47 is excited to increase the speed, and if the switch 36 is closed or the output terminal 38t of the detection circuit 38
) reaches a high level, the solenoid is energized and decelerated. When the switch 37 is closed, the solenoid is energized to cut off the fuel supply to the engine until a sensor (not shown) confirms that the engine has stopped. Control like this? A control program i for performing the calculation is stored in the iROM 13, and is performed using the flRAM 14i for storing necessary data during arithmetic control. During its execution, the control program in the ROM 33 is designed to repeatedly emit a high level pulse p from a specific output capacitor (12b1), so that the pulse interval t is shorter than the time t1. .

The period of such a pulse signal may be a constant period shorter than t, or it may be an irregular period.

The output capo) 12b IH lid 11 is connected to the trigger terminal of a monomulti vibrator (hereinafter referred to as "mono multi") 5, and is configured to be triggered by the pulse P1 emitted from the output capo) 12b1.

The time width of the pulse P2 that is triggered by the monomulti 51 is selected to be the above-mentioned time t1. Therefore, the microcomputer 10 operates normally and outputs the pulse PX at t.
□As long as the pulses are repeatedly emitted at shorter time intervals, the output of the monomulti 51 will be at a high level, and the interval t of pulses Pl will be
When 1) becomes 11, the output becomes low level. The output terminal of the mono multi 51 is an off-delay circuit 52
The output of this circuit 52 is connected to an inverter 53,
0PUII reset terminal 11 via OR gate 54
given to a. Another input of the OR gate 54 is connected to a power-on resetter (DO) path 55 for resetting the microcomputer 10 when the key switch 50 is turned on. When the key switch 5 is closed, the bare foot voltage circuit 56 interposed between the key switch 5o and the power-on reset circuit 55 is connected to the battery 3, and the voltage of the constant voltage circuit 56 gradually rises to its setting. voltage is reached. The power-on reset circuit 55 includes a series circuit of a Zener diode 55a and a resistor 55'b interposed between the output terminal of the constant voltage circuit 56 and body ground, and a collector connected to the cand of the Zener diode 55a via a resistor 55ci. The intermediate node of the series circuit is connected to the pace via a resistor 55d, and the transistor 55e has its emitter all body grounded.
The collector of 5e is connected to an OR gate 54Vc as an output terminal. The Zener voltage of the Zener diode 55a is selected to be slightly lower than the set voltage of the constant voltage circuit 56. Therefore, the transistor 55eI/'i remains off until the output of the constant voltage circuit 56 exceeds the Zener voltage of the Zener diode 55a after the key switch 5o is turned on.
For this reason, the 11 set terminal 11ai of OP[T11 becomes high level 0PUII, and therefore the microcomputer 1O#:t is reset. 0PUII due to f'L
) control returns to the start state. After that, when the output of the constant voltage circuit 56 exceeds the Zener voltage, the transistor 55
ei turns on, the input of the OR gate 54 becomes low level, and C
! The reset of PTTII is released and the required control becomes possible.

The inventive machine configured as described above performs the reset operation at power-on as described above by closing the key switch 50.
The cutting height and vehicle speed are adjusted by the microcomputer 10rC. As shown in FIG. 3 (0), bass and ry bass P1 are emitted one after another from this capo 12b1, so the mono multi 51 output maintains a high level.
The output of the inverter 53 is at a low level (e+'3 in Figure 3).

However, if an abnormality occurs in 0Pt711 for some reason and the pulse P is not emitted, the pulse P disappears after a time t1 after the last pulse p1/ is emitted, and the monomultiple The output 51 is at low level 7 as shown in Figure 3 (b). During the delay time t2 of the off-delay circuit 52 after changing to low level as shown in FIG.
If 1# is issued, the monomulti 51 is triggered as shown by the 2-point @ line, and the output of the inverter 53 continues to be at a low level as shown by the 2-dot chain line, but the pulse P1 is not issued within time t2. If there is no f′L, off-delay circuit 5
2 output becomes low level, and the output of inverter 53 becomes high level as shown in FIG. In such a case, the off-delay circuit does not reset the CPU 11 and continues automatic control, but if the pulse Ayu is not emitted for times t and +t, the OPU 11'5 is reset and returned to the start state. return. This prevents various actuators such as the solenoid 45 from being erroneously controlled by the microcomputer-0 in which an abnormality has occurred.

If the microcomputer is reset in this way, the automatic control will not work and the driver will notice the abnormality, but in order to more reliably report the problem, the inverter 5
It would be nice to have an LED or the like that lights up when the output of No. 3 becomes high level. Also, if the microcomputer is reset in this way, there is a possibility that the malfunction is temporary, so it is best to turn off the -H key switch 50 and completely close the circuit again to check f'L. . This is because if the normal state has been restored at the time of re-closing, automatic control becomes possible again, and if there is a failure, Fi immediately enters the reset state. Furthermore, it is also possible to have a configuration in which program execution is automatically restarted after a power-off time has elapsed after a reset.

As described above, according to the present invention, dangers due to runaway of the automatic control device can be avoided, and a highly safe and reliable working machine can be realized.

[Brief explanation of the drawing]

Embodiments of the present invention are shown in the drawings, in which Fig. 1 is a schematic side view of a combine harvester, Fig. 2 is a leg circuit diagram of an automatic control device, and Figs. 3 (a), (b), ( c) is a time chart for explaining the operation. 10...Microcomputer 11...CPU1
2... Input/output interface U2a... Input port 12b... Output port 13... ROM51.
...Mono multi 52...Off delay circuit 55...
・Power-on reset circuit patent applicant Noboru Kono, agent patent attorney for Yanmar Agricultural Machinery Co., Ltd. Figure 41

Claims (1)

[Claims] 1. In a work machine equipped with a 90-motion control device using a -r microcomputer, a control program is configured to cause a predetermined output port of the microcomputer to emit a pulse signal of a fixed period or an irregular period, and The 9th match in which the is not emitted for more than a certain period of time is M1.
A working machine 0 having a configuration for resetting a black computer and having the following features: