JPH0160660B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to an internal combustion engine stopping device that stops an internal combustion engine when an abnormality that requires stopping the engine occurs. [Prior art] When the pressure of the lubricating oil of the internal combustion engine (hereinafter referred to as oil pressure) becomes abnormal, the temperature of the engine cooling water (hereinafter referred to as water temperature) becomes abnormally high, or when the engine is cooled. When the belt driving the fan breaks, etc., it is necessary to immediately stop the engine and perform inspection and repair, but conventionally, an indicator such as a lamp is turned on when the oil pressure becomes abnormal. Therefore, if the driver overlooked the display, he would not be able to stop the engine, which could result in damage to the engine. Therefore, the fuel supply control means that controls the supply of fuel to the internal combustion engine when in the de-energized state is maintained in the fuel supply permission state to permit the supply of fuel, and when the fuel supply control means is energized, the fuel supply control means is set to supply fuel. A fuel supply control actuator that is brought into a stopped state and stops the supply of fuel is provided, and when an abnormal condition that requires stopping the internal combustion engine occurs, an excitation command signal is given to the drive circuit of the actuator to energize the actuator. An internal combustion engine stopping device has been proposed. [Problems to be Solved by the Invention] However, in this stop device, when an abnormal condition occurs, the actuator is kept in an excited state as long as the key switch is closed, so if the driver forgets to turn off the key switch, the actuator coil It had the disadvantage of burning. Furthermore, in the conventionally proposed stopping devices, there is a possibility that an excitation command signal is applied to the actuator drive circuit until the oil pressure rises when the engine is started, causing the engine to stop, which poses a practical problem. Therefore, the inventors proposed the use of a timer circuit to delay the output of the excitation command signal until the oil pressure increases at the time of starting. A problem arose in that the timed operation of the timer circuit was completed and the timer circuit did not work effectively. The object of the present invention is to provide an internal combustion engine stop device that can reliably stop the engine when an abnormality occurs in oil pressure, water temperature, etc., and that can also prevent the actuator coil from burning out if the key switch is forgotten to be turned off. Our goal is to provide the following. [Means for Solving the Problems] The internal combustion engine stopping device to which the present invention is directed has a first
As seen in the embodiment shown in FIGS.
The fuel supply control means 4, which controls the supply of fuel to the internal combustion engine when in the excited state, is maintained in a fuel supply permission state to permit fuel supply, and when the fuel supply control means 4 is excited, the fuel supply control means 4 controls the supply of fuel to the internal combustion engine. It has a fuel supply control actuator 3 that brings it into a stopped state and stops the supply of fuel, and a charging control circuit 13 that charges the battery 1 by rectifying the output of the battery 1 and the generator 12 driven by the internal combustion engine. a power supply circuit 14; an actuator drive circuit 5 having a switch means 5a that is electrically connected to supply excitation current from the battery 1 to the actuator 3 when the excitation command signal Ve is supplied; and an off circuit that cuts off at least the output of the power supply circuit 14. a key switch 2 that can be switched between an on state that allows power to be supplied from the power supply circuit 14 and a starting state that energizes the starter motor for starting the engine while maintaining the on state; An abnormality signal output circuit 6 that outputs an abnormal signal Va when an abnormal condition that requires stopping the internal combustion engine occurs when drive power is supplied from the circuit 14, and an abnormal signal output circuit 6 that outputs an abnormal signal Va when the abnormal signal Va is generated. and an excitation command signal supply circuit that supplies an excitation command signal Ve. In the present invention, when the key switch 2 is in the on state, the power supply circuit 1 passes through the key switch 2.
4, and outputs power from a power supply circuit 14 through a conductive switch means 5a of an actuator drive circuit 5 when the key switch 2 is in an off state. The excitation command signal supply circuit includes a first timer circuit 7, a second timer circuit 9, and a timer control circuit 1.
0 and a reset circuit 8. The reset circuit 8 is supplied with drive power from the power supply circuit 14 when the key switch 2 is in the on state, and resets the first timer circuit 7 and the timer control circuit 1 while the key switch 2 is switched to the starting state.
0 are supplied with first and third reset signals V _r1 and V _r3 , respectively. The first timer circuit 7 performs a timed operation for a first time period from the time when the key switch 2 is turned on, and outputs a stop operation permission signal V _sa after the timed operation ends. It is in a reset state while the output first reset signal V _r1 is applied. The second timer circuit 9 is supplied with drive power from the power supply circuit 14 through the power supply circuit 11 . The second timer circuit 9 is reset when the second reset signal V _r2 is supplied from the timer control circuit 10, and while being reset, the timer circuit 9 stops its time-limited operation and outputs the second reset signal V _r2 . A timed operation is performed for a second time period from the time when the supply is stopped, and an excitation command signal Ve is given to the actuator drive circuit 5 during the timed operation. The timer control circuit 10 is supplied with driving power from the power supply circuit 14 through the key switch 2 when the key switch 2 is in the on state. It is reset when driving power is supplied and supplies the second reset signal V _r2 to the second timer circuit 9, and when the key switch 2 is turned off and the stop operation permission signal V _sa is input. When the abnormal signal Va is input in the state where
When the supply of the second reset signal V _r2 to the timer circuit 9 is stopped and the third reset signal V r3 is supplied after the supply of the second reset signal V _r2 is stopped, the timer circuit 9 is reset and the second reset signal V _r3 is supplied. A second reset signal V _r2 is supplied to the timer circuit 9. The abnormality signal output circuit 6 includes a circuit that automatically outputs an abnormality signal by detecting engine oil pressure, cooling water temperature, fan belt abnormality, load abnormality, etc. It also includes a circuit that outputs an abnormal signal when the pushbutton switch is closed in an emergency. "Signal" in the above arrangement includes not only voltage or current signals, but also signals provided by the on or off state of the electrical switch means. [Operation of the invention] In the above configuration, the first time limit of the first timer circuit 7 is set after the engine has started and the power supply to the starter motor has been cut off (when the key switch 2 is returned from the starting state to the on state). (after the engine oil pressure rises to a normal value), or is set to be slightly longer than the time required for the engine oil pressure to rise to a normal value. The second time limit of the second timer circuit 9 is set to be approximately equal to or slightly longer than the time required for the engine to actually stop after the fuel supply to the engine is stopped. There is. When the key switch 2 attached to a device driven by an engine (vehicle, agricultural equipment, civil engineering machine, engine generator, engine welding machine, etc.) is turned on, the first timer circuit 7 starts a timed operation. The timer control circuit 10 is reset and the second reset signal V _r2 is supplied to the second timer circuit 9. The abnormality signal output circuit 6 detects the engine's lubricating oil pressure (oil pressure), engine cooling water temperature (water temperature), etc., and outputs an abnormality signal Va when the oil pressure, water temperature, etc. are in an abnormal state. do. Before the engine is started, the oil pressure is low, so an abnormal signal is sent from the abnormal signal output circuit 6 that detects the oil pressure.
Va is output, but since the first timer circuit 7 does not output the stop operation permission signal V _sa until the first timer circuit 7 finishes its timed operation, the timer control circuit 10 The second reset signal V _r2 continues to be supplied to the circuit 9. Therefore, the second timer circuit 9 has stopped its timed operation, and the excitation command signal Ve is not supplied to the actuator drive 5.
At this time, the actuator 3 is not excited, so
When the key switch 2 is switched to the starting state and the starter motor is energized, fuel is supplied to the engine.
The engine starts. Since the engine does not start after one operation, when the key switch 2 is switched to the starting state again, the reset circuit 8 supplies the first reset signal V _r1 to the first timer circuit 7. 7 is reset. When the first timer circuit 7 is reset, it stops the timed operation if it is in a timed operation, and stops outputting the stop operation permission signal _Vsa if the timed operation is completed, and returns to the original state. If the first timer circuit 7 is reset to the original state by the first reset signal _Vr1 output from the reset circuit 8 every time the key switch 2 is switched from the on state to the starting state, the engine will be difficult to start. No matter how many times the starting operation (repetition of ON state and starting state) is repeated, the timed operation of the first timer circuit 7 will never be completed before the engine starts. The engine starts and key switch 2
When the first timer circuit 7 is turned back on, the first timer circuit 7 starts its time-limiting operation again. After the engine starts, the first
When the timer circuit 7 finishes its timed operation, the first timer circuit 7 outputs a stop operation permission signal V _sa . At this time, the oil pressure of the engine has become normal, so the timer control circuit 10 continues to output the second reset signal V _r2 to the second timer circuit 9, and the second timer circuit 9 receives the excitation command signal Ve. It is in a state where it is not outputting. Therefore, the actuator 3 is not excited, fuel is normally supplied to the engine, and the engine is maintained in a normal operating state. When an abnormal phenomenon such as a drop in oil pressure or an abnormal rise in water temperature occurs during engine operation, the abnormal signal output circuit 6 outputs an abnormal signal Va. At this time, the first timer circuit 7 has already finished its timed operation and outputs the stop operation permission signal V _sa , so when the abnormal signal Va is output, the timer control circuit 10 starts the second timer circuit. The supply of the second reset signal to 9 is stopped.
As a result, the second timer circuit 9 starts a timed operation and supplies the excitation command signal Ve to the actuator drive circuit 5 that drives the actuator 3. As a result, the actuator 3 is energized and the supply of fuel to the engine is blocked. Therefore, the engine is stopped, and the engine is prevented from being damaged or its auxiliary equipment becoming unusable due to the continuation of the abnormal condition. When the timed operation of the second timer circuit 9 ends, the supply of the excitation command signal Ve is stopped.
The actuator drive circuit 5 brings the actuator 3 into a de-energized state, thereby preventing the coil of the actuator 3 from burning out. Furthermore, each time the key switch 2 is switched to the starting state, the third reset signal V _r3 is supplied from the reset circuit 8 to the timer control circuit 10, and the timer control circuit 10 enters a state in which it outputs the second reset signal V _r2 . It is about to be reset. Therefore, even if the abnormal signal Va is temporarily output due to noise or the like while the engine is running and the engine stops, it can be restarted by switching the key switch 2 to the starting state without returning it to the off state. This allows the engine to be restarted quickly. Furthermore, in order to arbitrarily stop the engine during normal operation, when the key switch 2 is turned off, the output of the second reset signal V _r2 from the timer control circuit 10 is stopped and the second timer circuit 9 is activated to the second time limit. The excitation command signal Ve is supplied to the actuator drive circuit 5 for a certain period of time by performing a timed operation. Therefore, the actuator 3 is energized for a certain period of time to stop supplying fuel to the engine, and the engine is stopped during this period. When the timed operation of the second timer circuit 9 ends, the actuator 3 becomes de-energized, and the fuel supply control means 4 is brought into a fuel supply permission state. Therefore,
While the engine is stopped, the fuel supply control means is maintained in a fuel supply permission state. As described above, the stop device of the present invention is provided with the first timer circuit 7 that starts a timed operation when the key switch 2 is returned from the starting state to the on state, so that the actuator 3 is excited when the engine is started. Since this prevents the engine from starting, the engine can be started without any problems. In particular, in the present invention, each time the key switch 2 is switched to the starting state, the first timer circuit 7 is reset by the output of the reset circuit 8 (first reset signal V _r1 ) to return to the original state.
Even if you repeat the starting operation many times because the engine is difficult to start, the first
This can prevent the timed operation of the timer circuit 7 from being completed. Furthermore, when the engine stop device is activated, it is often the case that the key switch 2 is forgotten to be turned off because the engine is stopped; however, in the present invention, the second timer circuit 9
actuator 3 when stopping the engine.
is excited only for a certain period of time (during the second time period), so it is possible to prevent the coil of the actuator 3 from burning if the key switch 2 is forgotten to be turned off. Furthermore, each time the key switch 2 is switched to the starting state, the third reset signal V _r3 is supplied to the timer control circuit 10 to reset the timer control circuit 10 to a state in which it outputs the second reset signal V _r2 . Even if the abnormality signal Va is temporarily erroneously output due to noise during engine operation and the engine stops, the engine can be restarted quickly by switching to the starting state without returning key switch 2 to the off state. Can be done. [Examples] Examples of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows an embodiment in which the present invention is applied to a diesel engine.
is a device driven by an engine, such as a battery mounted on a vehicle. This battery 1 is charged via a charging control circuit 13 by the output of a generator 12 driven by the engine. The power supply circuit 1 is powered by the battery 1, generator 12, and charging control circuit 13
4 are configured. The power supply circuit 14 supplies power to a load such as a headlamp, and at the same time supplies power to each part of the circuit of the stop device of the present invention. 2 is a key switch operated by a key, with contacts B,
It has OFF, BR, C, and R1, and by operating the key, it changes from the OFF state where the output of the power supply circuit 14 is cut off, to the preheating state where power is supplied to the preheating plug of the diesel engine, and to each part of the stop device. The switch is sequentially switched to the on state that supplies power and the starting state that supplies power to the starter motor that starts the engine, and when switched to the starting state, the on state is maintained, and when the key is released from the starting state, the switch automatically turns off. It's starting to turn back on. When this key switch is in the off state, preheating state, on state, and starting state, each contact is connected as shown in Table 1.

[Table] Table 1 above shows that in each state, the contacts marked with circles are electrically connected to each other. Reference numeral 3 denotes an actuator that operates a fuel supply control means 4 that stops or allows the supply of fuel to the engine. This actuator operates the fuel supply control means 4 using a solenoid, motor, etc. as a driving source, and allows fuel to be supplied to the internal combustion engine when it is in a non-energized state, and when it is energized, it allows fuel to be supplied to the engine. The fuel supply control means 4 is operated to stop the supply. In the case of a diesel engine, the fuel supply control means 4 is a fuel injection pump, and the fuel injection pump is generally switched between a state in which fuel supply is permitted and a state in which fuel supply is stopped by operating a lever. ing. Reference numeral 5 denotes an actuator drive circuit for driving the actuator 3, which includes a switch means that becomes conductive when the excitation command signal Ve is input and supplies an excitation current to the actuator 3. 6
When the oil pressure, water temperature, etc. become abnormal, when the fan belt breaks, when the emergency button is pressed, etc.
This is an abnormal signal output circuit that outputs an abnormal signal Va when an abnormal situation that requires the engine to be stopped occurs. 7 is a first timer circuit, and this timer circuit is
When the key switch 2 is turned on (when the B contact and the BR contact are connected), the timed operation is performed during the first time period, and after the timed operation ends, the stop operation permission signal V _sa is output. However, while the first reset signal V _r1 is applied from the reset circuit 8, it is in the reset state and stops the timed operation or stops outputting the stop operation permission signal V _sa . 9 is a second timer circuit, and this timer circuit is
It is configured to give the excitation command signal Ve to the actuator drive circuit 5 only during the timed operation during the second time period, and when the key switch 2 is in the on state, the second reset signal V _{r2 is} sent from the timer control circuit 10.
is supplied and the timed operation is stopped while the reset signal V _r2 is supplied. 10 is a timer control circuit, and this control circuit outputs the third reset signal V from the reset circuit 8 when the key switch 8 is switched from the OFF state to the ON state or after the output of the second reset signal V _r2 is stopped. When _r3 is supplied, it is reset and the second
A second reset signal V _r2 is output to the timer circuit 9 of the second timer circuit 9 to stop the timer operation of the second timer circuit 9. The timer control circuit 10 receives a stop operation permission signal when the key switch 2 is in the off state.
If the abnormal signal Va is output while V _sa is being output, the supply of the second reset signal V _r2 to the second timer circuit 9 is stopped, and the second timer circuit 9 is activated to perform a timed operation. have them do it. In this embodiment, the timer control circuit 10 is a gate circuit 10 that outputs the set signal Es when the abnormal signal Va and the stop operation permission signal V _sa are input simultaneously.
A and is set when the set signal Es is applied to prevent the output of the second reset signal V _r2 from the terminal, and when the key switch 2 is switched to the preheating state and when the key switch 2 is switched to the starting state. and a flip-flop circuit 10B which is reset by being supplied with a third reset signal _Vr3 . The reset circuit 8 supplies first and third reset signals to the first timer circuit 7 and the timer control circuit 10, respectively, when the key switch 2 is switched to the preheating state and the starting state. In this embodiment, first and second timer circuits 7 and 9, a reset circuit 8, and a timer control circuit 10 are used.
This constitutes an excitation command signal supply circuit that supplies an excitation command signal Ve to the actuator drive circuit 5 when an abnormal signal Va indicating that an abnormal condition that requires stopping the internal combustion engine has occurred is output. . 11 outputs power from the power supply circuit 14 through the key switch 2 when the key switch 2 is in the on state, and outputs power from the power supply circuit 14 through the conductive switch means of the actuator drive circuit 5 when the key switch 2 is in the off state. This is a power supply circuit. Referring to FIG. 2, there is shown an embodiment that embodies the configuration shown in FIG. 1 above. In Figure 2,
The actuator 3 includes a solenoid 3a and a plunger 3b driven by the solenoid, and one end of the solenoid 3a is grounded. In this actuator, when the solenoid 3a is energized, the plunger 3b operates a fuel supply control means (not shown) to stop the fuel supply, and when the solenoid 3a is de-energized, the plunger 3b returns and fuels the fuel. The supply control means is brought into a fuel supply permission state. The actuator drive circuit 5 includes a transistor 5a whose collector is connected to the non-grounded terminal of the solenoid 3a, a resistor 5b connected between the base and emitter of the transistor 5a, and a transistor 5a whose emitter is grounded and whose collector is connected via a resistor 5c.
A transistor 5d whose emitter is grounded and whose collector is connected to the base of the transistor 5d, and a resistor 5 connected between the base and emitter of the transistor 5e.
f, a resistor 5g whose one end is connected to the base of the transistor 5e, a resistor 5h whose one end is connected to the base of the transistor 5d, and a diode 5i whose cathode is connected to the emitter of the transistor 5a.
and a diode 5j connected between the collector of the transistor 5a and the ground with the anode facing the ground side.
The anode of the diode 5i is connected to the B contact of the key switch 2 (the positive terminal of the battery 1). In this actuator drive circuit 5, when the transistor 5e is in a cut-off state and the transistor 5d is conductive, a base current flows through the transistor 5a, making the transistor 5a conductive, and when the transistor 5a is conductive, the power supply circuit 14 to the transistor 5a
actuator 3 through the emitter collector of
Excitation current is supplied to the solenoid 3a. The abnormal signal output circuit 6 is the BR of the key switch 2.
Indicator lamps (light emitting diodes may be used) 6a and 6b with one end connected to the contact, detection contacts 6c and 6d connected between the other ends of the indicator lamps 6a and 6b and ground, respectively, and the contacts 6c and 6d and the indicator lamp. Diodes 6e and 6f have their cathodes connected to the connection points with 6a and 6b, and their anodes are commonly connected, a diode 6g has its anode connected to the BR contact, and its emitter is connected to the cathode of the diode 6g, and its base is connected to a resistor 6i. It consists of a transistor 6h connected to a common connection point of diodes 6e and 6f via a transistor 6h, and a resistor 6j connected between the base and emitter of the transistor 6h. Contacts 6c and 6d are contacts provided on a detector that detects the oil pressure and water temperature of the engine, respectively. When the oil pressure falls below a set value, contact 6c closes, and when the water temperature exceeds the set value, contact 6d closes. is starting to close. In addition, if the detector for detecting oil pressure and water temperature is a non-contact type, contact points 6c and 6d
Of course, these are replaced by output non-contact switches (closed in the event of an abnormality) of each detector. In this abnormal signal output circuit 6, if the oil pressure or water temperature becomes abnormal and the contact point 6c or 6d closes while the key switch 2 is in the on state, the battery 1, the diode 6g, the resistors 6j, 6i, the diode 6e or 6f, and Contact 6c or 6
A current flows through d, and the indicator lamp 6a or 6
b lights up to indicate that an abnormality has occurred in the oil pressure or water temperature. At this time, a base current flows through the transistor 6h, making the transistor conductive, and an abnormality signal is output through the emitter collector of the transistor. Further, in this embodiment, a charging control circuit 13 is provided which receives the output of a generator 12 driven by the engine and supplies a charging current to the battery 1. A power supply circuit 14 is configured by the battery 1, the generator 12, and the charging control circuit 13. The charging control circuit 13 includes a detection terminal 13a, an abnormal signal output terminal 13b, and a DC output terminal 13c. The detection terminal 13a is connected to the BR contact of the key switch 2, and detects the output voltage of the power supply circuit in order to perform voltage control. This terminal 13a also serves as a power supply terminal, and when the regulator 13 does not generate a predetermined output from the generator 12,
Abnormal signal output terminal 13b using battery 1 as power source
Outputs an abnormal signal from. The battery 1 is charged by the DC voltage output from the DC output terminal 13c. An indicator lamp 17 is connected between the abnormal signal output terminal 13b and ground. Therefore, when the key switch 2 is held in the on state and the engine is stopped, the fan belt that transmits the rotation of the engine to the generator 12 and an engine cooling fan (not shown) is cut, and the generator 12 is stopped. When the output is stopped, the indicator lamp 17 lights up and an abnormality signal is output to the terminal 13b. That is, in this embodiment, the charging control circuit 13 forms part of the abnormality signal output circuit 6. The first timer circuit 7 is connected between the comparator 7a, the positive phase input terminal of the comparator 7a, and the power input terminal t1 (a constant voltage is applied from the power supply circuit 14 through the power supply circuit 11 described later). resistor 7c,
A capacitor 7d connected between the positive phase input terminal and the ground, a resistor 7e connected between the negative phase input terminal of the comparator 7a and the ground, and a resistor 7e connected between the negative phase input terminal and the power input terminal t1. The reset transistor 7g has a collector-emitter circuit connected in parallel to both ends of a capacitor 7d with its emitter facing the ground side. Comparator 7a
A power supply circuit 1 (to be described later) is connected between the power supply terminal T1 and the ground.
A predetermined voltage is applied through 1. In this timer circuit 7, the power input terminal t
When a constant voltage is applied to the capacitor 7d, the capacitor 7d is charged at a constant time constant through the resistor 7c, and a timed operation is performed. The resistors 7e and 7f constitute a reference voltage generation circuit, which divides the voltage applied between the power supply input terminal t1 and the ground and outputs a reference voltage E _r1 across the resistor 7e. and capacitor 7d
When the terminal voltage E _c1 is less than the reference voltage E _r1 obtained across the resistor 7e, the output terminal of the comparator 7a is grounded, and after the charging of the capacitor 7d is started, a predetermined operation time (first time period) is reached. ) has passed and the terminal voltage E _c1 of the capacitor 7d exceeds the reference voltage E _r1 , the output terminal of the comparator 7a becomes ungrounded (the stop operation permission signal V _sa is output). The reset circuit 8 consists of a series circuit of resistors 8a and 8b connected between the cathode of a diode 6g and ground, and a series circuit of resistors 8a and 8b whose emitter is grounded and whose base is connected to the resistors 8a and 8b.
A transistor 8c is connected to a connection point between the transistor 8c and the power input terminal t1.
a resistor 8d connected between the transistor 8
A diode 8e whose anode is connected to the collector of the diode 8e, a resistor 8g connected between the cathode of the diode 8e and ground, a resistor 8h whose one end is connected to the cathode of the diode 8e, and a cathode of which is connected to the other end of the resistor 8h. It consists of diodes 8i and 8j that are connected in common and whose anodes are connected to connections C and R1 of the key switch 2, respectively, and resistors 8g and 8j.
The connection point h is connected to the base of the reset transistor 7g of the first timer circuit 7. Further, a common connection point of the cathodes of diodes 8i and 8j is connected to a reset terminal R of a flip-flop circuit 10b, which will be described later. In this reset circuit 8, when the key switch 2 is turned on, a base current is supplied to the transistor 8c, making the transistor 8c conductive, and the base current flows to the reset transistor 7g through the resistor 8d and the diode 8e. prevent. Furthermore, when the key switch 2 is switched to the preheating state or the starting state, a base current is supplied to the transistor 7g through the diode 8i or 8j and the resistor 8h (the first reset signal V _r1
is supplied), the transistor 7g becomes conductive and short-circuits both ends of the capacitor 7d. As a result, the charge on the capacitor 7d is made zero, and the first timer circuit 7 is reset (at this time, the first timer circuit 7 cannot perform a time-limiting operation).
Further, when the key switch 2 is switched to the starting state or the preheating state, a third reset signal V _r3 is supplied to a reset terminal of a flip-flop circuit 10B, which will be described later, through diodes 8i and 8j. When the key switch 2 is in the on state and the reset control circuit 10 stops supplying the second reset signal V _r2 to the second timer circuit 9, that is, when the thyristor 10h and the transistor 10d are conductive. , when the third reset signal V _r3 is input to the reset terminal R of the flip-flop circuit 10B, the transistor 10c becomes conductive and the transistor 10d and the thyristor 10h are cut off. As a result, even if the key switch 2 is not returned to the off state, if the key switch 2 is switched to the starting state,
Flip-flop circuit 10B is reset. The second timer circuit 9 includes a comparator 9a, a resistor 9b connected between the positive phase input terminal of the comparator 9a and ground, and a capacitor 9c connected between the negative phase input terminal of the comparator 9a and ground. , a resistor 9d connected between the positive phase input terminal of the comparator 9a and the output terminal _t0 of the power supply circuit 11, and between the negative phase input terminal of the comparator 9a and the output terminal _t0 of the power supply circuit 11. a resistor 9e connected to the capacitor 9c, a transistor 9f whose collector-emitter circuit is connected in parallel to both ends of the capacitor 9c with the emitter facing the ground side, and a transistor 9f.
A 9g resistor connected in parallel between the base and emitter of
and a resistor 9h, one end of which is connected to the base of a transistor 9f, and the other end of the resistor 9h is connected to the output terminal of a flip-flop circuit 10B, which will be described later, together with the other end of the resistor 5g of the actuator drive circuit 5. . The gate circuit 10A consists of resistors 10a and 10b, one end of which is connected to the output terminal of the comparator 7a, the other end of the resistor 10a is connected to the collector of the transistor 6h of the abnormal signal output circuit 6, and the other end of the resistor 10b is connected to the anode. It is connected to the abnormality signal output terminal 13b of the charging control circuit 13 via a Zener diode 15 whose cathode is directed toward the resistor 10b and a diode 16 whose cathode is directed toward the Zener diode. In this second timer circuit 9, a capacitor 9c is charged through a resistor 9e to perform a timed operation. And the terminal voltage of the capacitor 9c
When E _c2 is less than the reference voltage E _r2 obtained across the resistor 9b, the output terminal of the comparator 9a becomes ungrounded (a state in which the excitation command signal Ve is supplied), and the terminal voltage E _c2 of the capacitor 9c becomes When the reference voltage E _r2 across the resistor 9b is exceeded, the output terminal of the comparator 9a becomes grounded (a state in which the excitation command signal Ve is not supplied). A flip-flop circuit 10B, which constitutes a timer control circuit together with the gate circuit 10A, is connected between a transistor 10c whose emitter is grounded, a transistor 10d whose emitter is grounded and whose base is connected to the collector of the transistor 10c, and the base-emitter of the transistor 10c. a resistor 10e whose one end is connected to the base of the transistor 10c, and a resistor 10f whose one end is connected to the base of the transistor 10c.
a resistor 10g connected between the collector of the transistor 10d and the power supply terminal t2, a thyristor 10h whose cathode is connected to the collector of the transistor 10d, and a resistor 10 whose one end is connected to the anode of the thyristor 10h.
and a Zener diode 10j whose cathode is connected to the anode of the thyristor 10h.The other end (reset terminal R) of the resistor 10f is connected to the common connection point of the cathodes of the diodes 8i and 8j of the reset circuit 8, The gates (set terminals S) of the gate circuit 10A are respectively connected to the connection points of the resistors 10a and 10b of the gate circuit 10A. The other end of the resistor 10i is the diode 6g.
is connected to the BR contact of key switch 2 through
The anode (output terminal Q) of the Zener diode 10j is connected to the common connection point of the resistors 5g and 9h. The power supply circuit 11 includes a diode 11a whose anode is connected to the contact BR of the key switch 2 through a diode 6g, a capacitor 11b connected between the cathode of the diode 11a and the ground, and a constant voltage using the voltage across the capacitor 11b as input. and a diode 11d whose cathode is connected to the non-ground terminal of the capacitor 11b, and the non-ground terminal (output terminal T ₀ ) of the capacitor 11b is connected to the power supply terminals T1 and Each is connected to T2. Further, the output terminal _t0 of the regulator 11c is connected to the power supply terminal t1 of the first timer circuit 7 and the power supply terminal t2 of the flip-flop circuit 10B. Next, the operation of the above embodiment will be explained. In the above embodiment, the first time period of the first timer circuit 7 (the time from the start of charging of the capacitor 7d until the terminal voltage E _c1 of the capacitor exceeds the reference voltage E _r1 ) is the period when the engine is started. , after the power supply to the starter motor is cut off (after the key switch 2 is turned back from the starting state to the on state), the time required for the oil pressure of the engine to rise to the normal value is approximately equal to or slightly longer than the time ( For example, it is set to about 6 seconds).
Further, the second time limit of the second timer circuit 9 (the time from the start of charging of the capacitor 9c until the terminal voltage of the capacitor exceeds the reference voltage V _r2 ) is as follows:
The time period is set to be approximately equal to or slightly longer than the time required for the engine to actually stop after the fuel supply to the engine is stopped (for example, about 25 seconds). When the key switch 2 attached to a device driven by an engine (vehicle, agricultural equipment, civil engineering machine, engine generator, engine welding machine, etc.) is turned on, the output of the battery 1 of the power supply circuit 14 supplies power. The signal is output from the output terminal _t0 of the circuit 11, and the capacitor 7d of the first timer circuit 7 is charged through the resistor 7c, thereby starting a timed operation. The abnormality signal output circuit 6 detects the engine's lubricating oil pressure (oil pressure), engine cooling water temperature (water temperature), etc., and outputs an abnormality signal Va when the oil pressure, water temperature, etc. are in an abnormal state.
Output. In the state before the engine is started, the oil pressure is low, so the abnormal signal Va is output from the abnormal signal output circuit that detects the oil pressure, but the first timer circuit 7 ends the timed operation. Until then, the first timer circuit 7 does not output the stop operation permission signal V _sa , so the output terminal of the flip-flop circuit 10B of the timer control circuit is in a non-grounded state (the thyristor 10h and the transistor 10d are cut off). Yes, Zener diode 10
j becomes conductive and the second reset signal V _r2 is output to the second timer circuit 9. Therefore, the second timer circuit 9 has stopped its timed operation. At this time, the base is also supplied to the transistor 5e, so the transistor 5e becomes conductive, forcing the output terminal of the comparator 9a and the base of the transistor 5d to be grounded. Therefore, the transistor 5d is in a cutoff state and no base current flows through the transistor 5a, so that the transistor 5a is not conductive and no excitation current is supplied to the actuator 3. At this time, the fuel supply control means is in a state where it can supply fuel. When the key switch 2 is switched to the preheating state, the preheating plug is energized and the inside of the cylinder of the engine is heated, and when the key switch 2 is then switched to the starting state and the starter motor is energized, fuel is supplied to the engine and the engine starts. Start. When the key switch 2 is switched to the preheating state or the starting state, the reset circuit 8 supplies the first reset signal V _r1 to the first timer circuit 7 .
stops the timed operation, the charge in the capacitor 7d is discharged, and the state returns to the original state. At this time, the third reset signal V _r3 from the reset circuit 8 is also input to the reset terminal R of the flip-flop circuit 10B, making the transistor 10c conductive. However, at this time, the first timer circuit 7 has been reset, no firing signal is applied to the gate of the thyristor 10h, and the state of the flip-flop circuit 10B does not change even if the transistor 10c becomes conductive.
When the engine is started and the key switch 2 is turned back on, the transistor 7g is cut off, so that the capacitor 7d of the first timer circuit 7 is charged again and a timed operation is started. When the engine is started, the generator 12 starts generating sufficient power and the charging control circuit 13
DC output is sent to power supply circuit 1 through key switch 2.
given to 1. After the engine starts, when the timed operation of the first timer circuit 7 ends, the output terminal of the comparator 7a of the first timer circuit becomes non-grounded (the stop operation permission signal V _sa is output). . At this time, the oil pressure of the engine is normal, so the thyristor 10h and transistor 10d are cut off in the flip-flop circuit 10B of the timer control circuit, and the second reset signal V _r2 to the second timer circuit 9 is output. continues to be. Therefore, the actuator drive circuit 5 is in a state where the excitation command signal Ve is not given (a state in which the transistor 5d is cut off).
It is in. At this time, the actuator 3 is not excited, fuel is normally supplied to the engine, and the engine is maintained in a normal operating state. When an abnormal phenomenon such as a drop in oil pressure or an abnormal rise in water temperature occurs during operation of the engine, the transistor 6h of the abnormal signal output circuit 6 becomes conductive and outputs an abnormal signal. At this time, the first timer circuit 7 has already finished its timed operation and is outputting the stop operation permission signal V _sa (the output terminal of the comparator 7a is in a non-grounded state), so the abnormal signal Va When is output, a firing signal is supplied to the thyristor 10h of the flip-flop circuit 10B. Therefore, the thyristor 10h becomes conductive and the transistor 10d becomes conductive. At this time, supply of base current to transistors 9f and 5e is blocked, so both transistors 9f and 5e
becomes blocked. As the transistor 9f enters the cut-off state, charging of the capacitor 9c is started, and the timer operation of the second timer circuit 9 is started. While this timed operation is being performed, the output terminal of the comparator 9a is ungrounded and the transistor 5e is cut off, so the transistor 5d is conductive and the base current flows through the transistor 5a. Therefore, the transistor 5a becomes conductive, causing an excitation current to flow through the actuator 3. This causes the fuel supply control means to stop supplying fuel, and the engine stops. At the stage when the engine is heading to a stopped state, the output of the generator 12 decreases, but when the output voltage of the charging control circuit 13 becomes lower than the voltage of the battery 1, power is thereafter supplied from the battery 1 through the power supply circuit 11. Terminal voltage of capacitor 9c
E _c2 exceeds the reference voltage E _r2 across resistor 9b, and the second
When the timed operation during the time period is completed, the comparator 9a
Since the output terminal of is grounded, the transistor 5d is cut off, and the transistor 5a is cut off. Therefore, the actuator 3 becomes de-energized, and the fuel supply control means returns to a state in which it can supply fuel. The above operation stops the engine and prevents the engine from being damaged or engine accessories from becoming unusable due to continued abnormal conditions. Further, after the engine has stopped, the fuel supply control means automatically returns to a state in which fuel supply is permitted in preparation for starting the next engine. Furthermore, upon completion of the timed operation of the second timer circuit 9, the supply of the excitation command signal is stopped, thereby preventing the coil of the actuator from burning out. When the key switch 2 is turned off to arbitrarily stop the engine during normal operation, the supply of base current to the transistors 9f and 5e is stopped, so the second timer circuit 9 performs a timed operation and the drive circuit 5 An excitation command signal is supplied to transistors 5d and 5a only during a second time period, thereby making transistors 5d and 5a conductive.
If key switch 2 is switched to the off state,
The output of the power supply circuit 14 is the conductive transistor 5a.
and is supplied to the power supply circuit 11 through the diode 11d. The actuator 3 is energized for a certain period of time due to the conduction of the transistor 5a, and the supply of fuel to the engine is stopped, and the engine is stopped during this period. After a certain period of time has elapsed, the output terminal of the comparator 9a becomes grounded and the transistor 5d is cut off, so that the transistor 5a is cut off. Therefore, the actuator 3 becomes de-energized, and the fuel supply control means is placed in the fuel supply permission state. Therefore, while the engine is stopped, the fuel supply control means is maintained in the fuel supply permission state. Even if no abnormal condition has occurred, even if the abnormal signal Va is temporarily output due to noise or the like and the engine stops, a reset circuit is set in the timer control circuit 10 every time the key switch 2 is switched to the starting condition. When the third reset signal V _r3 is supplied from 8, the transistor 10c becomes conductive, the transistor 10d is cut off, and the thyristor 10h is cut off, thereby resetting the flip-flop circuit 10B. Therefore, the engine can be restarted by switching the key switch 2 to the starting state without returning it to the off state, and the engine can be restarted quickly. In the above embodiment, since the target is a diesel engine, the R1 contact is provided on the key switch 2 to switch the key switch 2 to the preheating state. However, when the target is a gasoline engine, the R1
Contacts and circuits connected to the contacts are not required. Incidentally, in the case of a gasoline engine, since it does not have a fuel supply control means that has a function of completely cutting off fuel like a fuel injection pump normally installed in a diesel engine, when applying the present invention, It is necessary to provide a special valve that constitutes the fuel supply control means. The above-mentioned embodiment merely shows one example of the configuration of each part of the configuration of the present invention, and it goes without saying that the configuration of each part of the present invention is not limited to the above-described embodiment. [Effects of the Invention] As described above, according to the present invention, a first timer circuit that starts a timed operation when the key switch is returned from a starting state to an on state is provided, and the actuator is excited when the engine is started. Since this has been prevented, the engine can be started without any problem. Furthermore, when the engine stop device is activated, people often forget to turn off the key switch because the engine is stopped, but in the present invention, a second timer circuit is provided to switch the actuator to the second timer circuit when stopping the engine. Since the actuator is energized only during the time limit, it is possible to prevent the actuator coil from burning if the key switch is forgotten to turn off. In particular, according to the present invention, since the first timer circuit is reset by the first reset signal output from the reset circuit every time the key switch is switched to the starting state, the starting operation can be repeated several times when the engine is difficult to start. Even if this is repeated, it is possible to prevent the timed operation of the first timer circuit from being completed before the engine starts. Also, when the key switch is switched to the starting state, a third reset signal is given from the reset circuit to the timer control circuit,
Since the timer control circuit is reset to a state in which the second reset signal is output, even if an abnormal signal is temporarily output due to noise etc. while the engine is running and the engine stops, the key switch will not be returned to the OFF state. The engine can be restarted by switching to the starting state, and the engine can be restarted quickly.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the overall configuration of an embodiment of the present invention, and FIG. 2 is a circuit diagram showing an embodiment in which each part of FIG. 1 is embodied. 1...Battery, 2...Key switch, 3...
Actuator, 4...Fuel supply control means, 5...
... Actuator drive circuit, 6 ... Abnormal signal output circuit, 7 ... First timer circuit, 8 ... Reset circuit, 9 ... Second timer circuit, 10 ... Timer control circuit, 11 ... Power supply circuit, 12... Generator,
13...Charging control circuit, 14...Power supply circuit.

Claims (1)

[Scope of Claims] 1. A fuel supply control means that controls the supply of fuel to the internal combustion engine when it is in a non-excited state is maintained in a fuel supply permission state to permit the supply of fuel, and when it is energized, the fuel supply control means controls the supply of fuel to the internal combustion engine. A fuel supply control actuator that brings the control means into a fuel supply stop state to stop the fuel supply; and a charging control circuit that rectifies the output of a generator driven by the battery and the internal combustion engine to charge the battery. an actuator drive circuit having a switch means that is turned on when an excitation command signal is supplied to supply an excitation current from the power supply circuit to the actuator; and an actuator drive circuit that cuts off at least the output of the power supply circuit. a key switch that can be switched between an on state that allows power to be supplied from the power supply circuit and a starting state that energizes a starter motor for starting the engine while maintaining the on state; an abnormality signal output circuit that outputs an abnormal signal when an abnormal condition occurs that requires stopping the internal combustion engine when power is supplied from the circuit; and an abnormal signal output circuit that outputs the excitation command signal to the drive circuit when the abnormal signal is generated. and an excitation command signal supply circuit that supplies an excitation command signal, wherein when the key switch is in an on state, the power from the power supply circuit is output through the key switch, and when the key switch is in an off state, the power is output from the power supply circuit. a power supply circuit that outputs power from the power supply circuit through the conductive switch means of the actuator drive circuit; a first timer circuit that performs an operation and outputs a stop operation permission signal after the timed operation ends, and is in a reset state while a first reset signal is applied; and a first timer circuit that receives drive power from the power supply circuit through the power supply circuit. is supplied, and is reset while the second reset signal is being supplied, and stops the timed operation while being reset, and during the second time period from the time when the supply of the second reset signal is stopped. a second timer circuit that performs a timed operation and supplies the excitation command signal to the actuator drive circuit during the timed operation; and a second timer circuit that supplies driving power from the power supply circuit through the key switch when the key switch is in an on state; It is reset when driving power is supplied and supplies the second reset signal to the second timer circuit, and when the key switch is switched to an OFF state and the stop operation permission signal is input. When the abnormal signal is input in the state, the supply of the second reset signal to the second timer circuit is stopped, and after the supply of the second reset signal is stopped, the third reset signal is input. a timer control circuit that is reset when supplied and supplies the second reset signal to the second timer circuit; and a timer control circuit that is supplied with drive power from the power supply circuit when the key switch is in an on state, and that the key switch is activated. An internal combustion engine stopping device comprising: a reset circuit that supplies the first and third reset signals to the first timer circuit and the timer control circuit, respectively, while the engine is switched to a starting state.