JPH0777067A - Engine stop device - Google Patents

Abstract

(57) [Abstract] [Purpose] When a fuse inserted in series with a key switch is blown, it is displayed that it has blown, and when an abnormality that causes an overcurrent occurs, the fuse is surely blown.
When there is no abnormality that causes excessive current, the operation can be temporarily continued. [Constitution] A stop motor is supplied with current through a break-side contact of a stop relay inserted in a circuit in which current disappears when the key switch is cut off, and a separate contact interlocking with the key switch. And a circuit that supplies the power supply voltage to the stop relay via this separate contact and the first reverse current prevention diode, the second reverse current prevention diode inserted on the load side of the first fuse, and the second reverse current prevention diode. Equipped with a display circuit that displays the potential on the power supply side of the backflow prevention diode in the driver's seat, connect a second fuse in series with another contact, and display it in the driver's seat when the fuse is blown. When the fuse is blown, the stop relay is held and the engine can be stopped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is used to stop the operation of a diesel engine. The present invention is a device developed for large vehicles, but can be widely used as a stop device for diesel engines.

[0002]

2. Description of the Related Art Unlike a gasoline engine having a spark plug, a diesel engine does not stop immediately even if the power supply to the electric system of the engine is cut off by a key switch. Conventionally, a device that shuts off the fuel supplied to the engine or lowers the air pressure in the cylinder by interlocking with the operation of the key switch so that the engine stops only by operating the key switch has been widely known. .

As an engine stopping device for this purpose, there is widely known a technique for automatically starting and rotating a stop motor when a key switch is turned off to move a stop lever of an injection pump to cut off fuel supply to an engine. ing. This device is described in detail in JP-A-3-57829.

[0004]

Although the above-mentioned device is a convenient device, as shown in FIG. 2, the key switch 1 is turned on.
If the first fuse 4 inserted in series with the key switch 1 is blown while the vehicle is operating, that is, while the vehicle is operating, the engine stop device has cut off the power supply voltage. Is in the same state as when was turned off. It is a rare phenomenon that a fuse actually blows. It is necessary for the fuse to blow in the event of an anomaly that causes an excessive current in the circuit. In such a case, it is not always appropriate for the engine stopping device to immediately execute the steps to stop the engine. When the fuse blows, it is desirable to inform the driver of this and continue driving the vehicle to a position where the fuse can be replaced.

The present invention has been made against such a background, and when a fuse inserted in series with a key switch is blown, the fuse is displayed to the driver, and an abnormality causing an excessive current occurs. It is an object of the present invention to provide an engine stop device capable of reliably continuing the operation in the case where the fuse is surely blown, and when there is no abnormality causing an excessive current.

[0006]

The present invention relates to an engine stop of a diesel engine, and a stop relay inserted in a circuit in which a power supply voltage disappears when a key switch is in a cutoff state, and a break of this stop relay. In an engine stop device including a stop motor to which current is supplied via a side contact, a first fuse is connected in series to the key switch, and another contact interlocking with the key switch, the other contact, and A circuit that supplies the power supply voltage to the stop relay via one backflow prevention diode, a second backflow prevention diode inserted on the load side of the first fuse, and a second backflow prevention diode And a display circuit for displaying the electric potential on the power source side to the driver's seat, and a second fuse connected in series with the separate contact. And wherein the door.

The second fuse is preferably inserted in a relay circuit of a battery switch capable of interrupting the power supply voltage near the battery terminal.

[0008]

When the first fuse (4) connected in series to the key switch (1) is blown for some reason, the stop relay (2) is connected via the separate contact (5) linked with the key switch (1). ) Is supplied with current, the stop circuit does not operate immediately. Since the second fuse (9) is inserted in series also in this separate contact (5), if there is a cause of an overcurrent due to an abnormality in the load side circuit, the second fuse (9) 9) also melts and prevents troubles caused by abnormalities. If the fuse blows due to another cause even if there is no abnormality in the load side circuit, the stop relay (2) is held by the power supply voltage supplied from another contact (5) and the display circuit (8) Indicate that the fuse is blown in the driver's seat.

By connecting the second fuse (9) in common with the relay circuit of the battery switch (15), if the second fuse (9) is blown for some reason, the battery switch (15) is activated. The driver can know this because it is gone.

[0010]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a diagram showing a configuration of a main part of an embodiment of the present invention.

In the embodiment of the present invention, a current is supplied through a stop relay 2 inserted in a circuit in which the power supply voltage disappears when the key switch 1 is turned off, and a break side contact B of the stop relay 2. Stop motor 3
And a battery switch 15 and a battery relay 10. Further, as a feature of the present invention, a first fuse 4 is connected to the key switch 1 in series, and another contact 5 interlocking with the key switch 1 is provided. Stop relay 2 which stops the power supply voltage via contact 5 and first backflow prevention diode 6
And a second backflow prevention diode 7 inserted into the load side of the first fuse 4, and a display circuit 8 for displaying the power supply side potential of the second backflow prevention diode 7 on the driver's seat. And a second fuse 9 connected in series with the separate contact 5.

The second fuse 9 is a fuse having a fusing current value or more than that of the first fuse 4, and the battery switch 15 capable of cutting off the power supply voltage near the battery terminal.
Is inserted into the battery relay 10.

An arm 12 is mechanically connected to the stop motor 3, and the arm 12 is connected via a spring 13 and a cable 14 to an injection pump stop lever 11 provided in an injection pump (not shown). Stop motor 3
The change-over switch 3b provided inside is configured to be switched and driven by the motor 3a, and contacts the contact C while the engine is operating, and contacts the contact D when the engine is stopped. The motor 3a rotates normally or reversely depending on the current direction.

The stop relay 2 is composed of a relay coil 2a and a changeover switch 2b which switches between the make side contact A and the break side contact B by the relay coil 2a, and the battery relay 10 is constituted by the relay coil 1a.
0a and a relay switch 10b that opens and closes by the relay coil 10a, and shuts off the battery relay 10 to the power supply circuit by operating the power source 17 side from the break side contact B of the stop relay 2. A battery relay 10 which includes a battery switch 15 and disconnects the break-side contact B and the power supply 17 by the battery switch 15.
It is connected by a circuit 18 different from the circuit passing through.

Further, the display circuit 8 is composed of an indicator lamp 8a and a device 8b which is frequently used during operation, such as a radio circuit or an exhaust brake circuit, and a first fuse 4 and a first fuse 4 via an operation switch 16. It is connected between the two reverse prevention diodes 7.

Next, the operation of the embodiment of the present invention thus constructed will be described.

In the normal engine stop operation, when the key switch 1 is operated to be in the open state, the separate contact 5 is also operated in the open state, and the relay coil 2 of the stop relay 2 is opened.
The supply of current to a is cut off. By this current interruption, the changeover switch 2b is switched from the make side contact A to the break side contact B as shown by the broken line in FIG. At this time, the changeover switch 3b of the stop motor 3 is connected to the contact C side shown by the solid line.

At this time, the battery switch 15 is still in the closed state, and the battery relay 10 is turned off from the power supply 17.
The relay switch 10b is closed while the relay coil 10a is supplied with current, but the key switch 1 connected in series with the relay switch 10b is already open. Therefore, the current from the power supply 17 is not supplied to the relay coil 2a of the stop relay 2, and the changeover switch 2b is held in a state of being connected to the break side contact B.

For that purpose, the battery switch 15 is subsequently connected.
Is operated to open the relay coil 10a and the relay switch 10b is opened to cut off the current supply, or the battery switch 15 is not operated and the relay switch 10b of the battery relay 10 is closed. However, the changeover switch 2b of the stop relay 2 remains switched to the break-side contact B regardless of the operation of the battery switch 15.

On the other hand, the current from the power source 17 is supplied to the motor 3a through the circuit 18 branched from the battery relay 10 side, the contact C through the changeover switch 3b, as shown by the solid line arrow in FIG. , The motor 3a is driven in the direction to stop the fuel injection, and the arm 12 is rotated to rotate the injection pump stop lever 11 provided in the injection pump (not shown) via the spring 13 and the cable 14 to the engine. To stop the fuel supply. As a result, the engine is completely stopped regardless of whether the battery switch 15 is opened or closed.

When the motor 3a rotates the arm 12 to reach the fuel stop position, the changeover switch 3b in the stop motor 3 includes a cam, rod, spring (not shown) disclosed in Japanese Patent Laid-Open No. 3-57829. ) Switches to the contact D side indicated by the broken line, and the motor 3a in which the current supply from the power source 17 is cut off stops driving.

Next, the starting operation from the engine stopped state will be described.

When the battery switch 15 is operated to be in the closed state, current is supplied from the power supply 17 to the relay coil 10a of the battery relay 10, and the relay coil 10a closes the relay switch 10b. Here, when the key switch 1 is operated to be in the closed state, the current from the power supply 17 is supplied to the relay coil 2a of the stop relay 2 via the relay switch 10b and the key switch 1.

In the relay coil 2a, the changeover switch 2b, which was connected to the break-side contact B, is switched and connected to the make-side contact A as shown by the solid line in FIG. By this changeover connection, the current from the power supply 17 is supplied to the motor 3a via the circuit 18 through the make-side contact A and the changeover switch 2b as shown by the broken line arrow.

The motor 3a is driven in the direction opposite to that when the engine is stopped, the arm 12 is rotated in the fuel injection direction indicated by the dashed arrow, and the injection pump stop lever 11 is moved to the fuel supply position via the spring 13 and the cable 14. return. At this time, the changeover switch 3b in the stop motor 3 is changed over to the contact C side as shown by the solid line by the above-mentioned cam, rod, spring, etc., and the current from the power supply 17 is cut off to stop the driving of the motor 3a. As a result, fuel injection becomes possible, and the engine can be started by operating the key switch 1.

The operation when the fuse blows, which is a feature of the present invention, will now be described.

If the first fuse 4 connected in series to the key switch 1 is blown for some reason while the key switch 1 is operated in the closed state, the key switch 1 is closed in conjunction with the key switch 1. The current from the power supply 17 is supplied to the stop relay 2 via the separate contact 5 and the first backflow prevention diode 6. Therefore, the stop relay 2 does not operate immediately and the changeover switch 2b
Is still connected to the make side contact A, and the changeover switch 3b of the stop motor 3 is still connected to the contact D side as shown by the broken line, and the first fuse 4 is blown. The engine stop due to a thing is avoided.

Since the second fuse 9 is inserted in series on the side of the separate contact 5, even if an abnormality occurs on the load circuit side and an excessive current flows, the second fuse 9 is blown and blows. Trouble caused by the abnormality is prevented from occurring.

When the first fuse 4 is blown for some other reason even if there is no abnormality on the load circuit side, and the operation switch 16 for connecting to the display circuit 8 is closed, it lights up. If the indicator lamp 8a that has been used is extinguished, or if a frequently used device 8b is connected to, for example, a radio, no sound is generated, and it is notified that the first fuse 4 has blown.

When the second fuse 9 is blown, the current supply to the relay coil 10a of the battery relay 10 is cut off, so that the battery switch 10b is opened, and the current to the stop relay 2 is cut off. Then, the engine is stopped by the above-mentioned operation.

In the above example, the case where the battery switch 15 is provided has been described. However, when the battery switch 15 is not provided, there is no battery relay 10 and the key switch 1 and the power source 17 are directly connected to each other. In that case, the operation is performed as described above.

[0032]

As described above, according to the present invention, when the first fuse connected in series to the key switch is blown, there is no abnormality that causes an overcurrent, so the operation is temporarily continued. In addition, it is possible to prevent the occurrence of an accident by notifying the driver that the fuse has blown by the display and causing the second fuse to blow when an excessive current is generated.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a main part of an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a main part of a conventional example.

[Explanation of symbols]

 1 Key Switch 2 Stop Relay 2a, 10a Relay Coil 2b, 3b Changeover Switch 3 Stop Motor 3a Motor 4 First Fuse 5 Separate Contact 6 First Backflow Prevention Diode 7 Second Backflow Prevention Diode 8 Display Circuit 8a Indicator Light 8b Device 9 Second fuse 10 Battery relay 10b Relay switch 11 Injection pump stop lever 12 Arm 13 Spring 14 Cable 15 Battery switch 16 Operation switch 17 Power supply 18 Circuit

Claims (2)

[Claims] 1. A stop relay inserted in a circuit in which a power supply voltage disappears when a key switch is turned off, and a stop motor to which a current is supplied through a break side contact of the stop relay. In the engine stop device, a first fuse is connected in series to the key switch, and the stop relay relays the power supply voltage via another contact interlocking with the key switch and the other contact and a first backflow prevention diode. And a second backflow prevention diode inserted on the load side of the first fuse, and a display circuit for displaying the potential on the power supply side of the second backflow prevention diode to the driver's seat, Further, the engine stopping device is provided with a second fuse connected in series with the separate contact. 2. The second fuse is a fuse having a fusing current value or more than that of the first fuse, and is inserted in a relay circuit of a battery switch capable of interrupting a power supply voltage in the vicinity of a battery terminal. Item 1. The engine stopping device according to item 1.