JPH0627814Y2 - Internal combustion engine automatic stop device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic stop device for an internal combustion engine, particularly a diesel engine, and more specifically, an actuator lock for stopping the operation of the engine by shutting off fuel or air. It relates to the ones that have lost the troubles caused by breakdowns.

[Prior Art] Unlike a gasoline engine, a diesel engine is generally stopped by shutting off fuel or air. In the past, in addition to the starter switch, the driver was allowed to close the fuel or air valve via a link or cable.
At present, it is widely practiced to operate an electrically operated actuator by a starter switch to close a fuel or air valve. In particular, when high reliability is required, a type is used in which once a signal is input to operate the actuator, the operating position is held unless a cancel signal is input.

Conventionally, this type of automatic stop device, as disclosed in Japanese Patent Application Laid-Open No. 50-53748, drives a shutoff element of a fuel or air valve by a motor, and feeds power to this motor is a rotary limit switch. And the starter switch, the motor is driven every half rotation according to ON / OFF of the starter switch to open / close the fuel or air valve.

[Problems to be solved by the invention] However, in the conventional device, if the shut-off element is locked by the stroke midway for some reason such as freezing of the link system, the fuel or air valve can be turned off simply by turning off the starter switch. It cannot be shut down and the engine cannot be stopped. In such a case, the driver usually performs an emergency stop operation of the engine, but since the motor is still energized to restore the shutoff element by turning off the starter switch, the shutoff element is still turned on. There is a problem that the armature coil of a motor designed for a short time in order to achieve both weight reduction and high-speed operation will burn out as a result of continuous energization to operate it and exceeding the rated current. It was

Although it is possible to use a special part such as a relay with a timer that shuts off the power after a certain time has passed after the starter switch is turned off, there is a problem in terms of price.

[Object of the Invention] The object of the present invention is to solve the above problems and effectively prevent the armature coil from burning even when the actuator is locked and the engine is stopped in an emergency. It is to provide an automatic stop device for an engine.

[Summary of the Invention] The present invention in line with the above object has a motor for driving a shut-off element such as fuel or air, and a rotating portion that rotates in synchronization with the motor. An automatic internal combustion engine including a limit switch that selectively blocks conduction from a power source to two output terminals and a starter switch that switches and connects one of the output terminals to the motor in response to ON / OFF. In the stop device, a relay contact is provided in a power supply path to the motor, a relay coil of the relay contact is connected to an AC generator, and a terminal of the starter switch that is turned on and off in conjunction with the starter switch is used. Is connected to a power source, the starter switch is turned off, and the power supply to the motor is cut off when the engine is brought to an emergency stop.

According to the above configuration, when the blocking element locks midway,
If the engine is forcibly stopped by performing an emergency stop operation after turning off the starter switch, the starter switch O
Since both FF and engine stop are compatible, the relay coil is released from energization, the relay contact is activated, the power supply path is opened, and the power supply to the motor is cut off.

[Embodiment] The embodiment of the present invention will be described below with reference to FIG.

As shown in FIG. 1, reference numeral 20 denotes a motor engine stop, which is a fuel cut type shutoff element (not shown) for shutting off fuel to stop a diesel engine, a motor 13 for driving the shutoff element, and a synchronous rotation with the motor 13. The well-known limit switch 12 is provided. One end of the motor 13 is connected to the h terminal when the starter switch 21 is in the OFF to ACC position, and is connected to the f terminal that is connected to the i terminal when the starter switch 21 is in the ON to START position, and the other end is connected to the limit switch 12
Is grounded in common with the contact plate 22 of.

The limit switch 12 controls energization of the motor 13 every half rotation, and among the three contact pieces, the contact pieces 23 and 24 located above and below are connected to the i terminal and the h terminal of the starter switch 21, respectively. The remaining contact piece 25 located in the center is connected to the battery 15 via the relay contact 27 of the relay 16.

The relay winding 28 of the relay 16 has a battery 15 when the starter switch 21 is in the ON to START position.
The terminal e connected to the terminal a connected to the load terminal L and the load terminal L of the AC generator 29 are connected in parallel, and the relay 1 is connected from both the starter switch side and the AC generator side.
6 can be activated. Reference numeral 30 is a backflow prevention diode provided between the load terminal L and the relay winding 28, 31 is a charging warning lamp, and 32 is a regulator.

Further, from the battery 15 to the central contact piece 25 of the limit switch 12, the lower contact piece 24, and the h of the starter switch 21.
Line from the battery 15, to the ground via the f terminal and the motor 13, and from the battery 15 to the ground via the central contact piece 25, the upper contact piece 23, the i terminal of the starter switch 21, the f terminal and the motor 13. Line constitutes a power supply circuit.

Now, in the above configuration, when the starter switch 21 is normally switched to the ON position to start the engine, the contact 27 of the relay 16 is turned ON by the bias from the starter switch side. At this time, the upper contact piece 23
The central contact piece 25 and the central contact piece 25 are closed via the disc electrode 33, and therefore the motor 13 is energized and rotated via the contact pieces 23 and 25 and the starter switch 21.
As a result, the fuel cut is released and the engine can be started. In this case, the disk electrode 33 of the limit switch 12 rotates synchronously with the motor 13, but the contact plate 22
When it rotates half a turn clockwise and comes into contact with the upper contact piece 23, the power supply to the motor 13 is cut off and stopped, and the cutoff element holds the release of the fuel cut.

Conversely, the starter switch 21 is used to stop the engine.
When the switch is switched to the OFF position, the bias from the starter switch side disappears, but while the engine is rotating, the relay contact 27 is kept ON by being biased from the AC generator side. At that time, the lower contact piece 24 and the central contact piece 25 are closed via the disk electrode 33, so that the motor 13 is energized and rotated via the contact pieces 25, 24 and the starter switch 21. , The blocking element is restored.
As a result, fuel is cut and the engine stops. During this time, the disc electrode 33 of the limit switch 12 stops when the contact plate 22 further turns clockwise by a half turn to the original position and opens the power supply circuit. When the engine is stopped, the relay 16 is turned off and the power supply circuit is cut off twice.

In the event of an abnormality, that is, when the actuator locks midway, the starter switch 21 is turned off to stop the engine.
Even if it is set to F and the motor 13 is energized, the engine does not stop because the motor 13 does not rotate. By the way, in the case of a diesel engine, when the engine does not stop, the operation is usually performed by forcibly stopping the engine by putting the gear in the 4th to 6th speeds and engaging the clutch while depressing the brake. Therefore, when this operation is performed, the engine stops, the bias from the AC generator side disappears, and the relay 16 turns off. When the relay 16 is turned off, even if the contact pieces 25 and 24 of the limit switch 12 are closed, the power supply to the motor 13 is cut off, and the power supply to the motor 13 or the power supply to the limit switch 12 is stopped.

In this way, unlike the case where the power supply circuit is opened and closed only by the limit switch 12 and the motor continues to be energized even after the engine is stopped, the power supply is turned on regardless of the state of the limit switch 12 when the starter switch is OFF and the engine is stopped. Since the relay 16 for opening the circuit is additionally provided, the power supply to the motor 13 is forcibly stopped when both the conditions of the starter switch OFF and the engine stop are satisfied.
Even if the actuator is locked, the armature coil can be prevented from burning.

Although the relay contact 27 of the relay 16 is provided between the battery 15 and the central contact piece 25 of the limit switch 12 in the above embodiment, the present invention is not limited to this.
It may be anywhere in the line forming the power supply circuit described above.

[Effect of the Invention] In summary, according to the present invention, the following excellent effects are exhibited.

(1) A relay contact is provided in the power supply path to the motor, the relay coil is connected to the AC generator, and the power supply is connected via the terminal of the starter switch that is turned on and off in conjunction with the starter switch. When the engine does not stop even when the switch is turned off, the power supply to the motor can be cut off by an emergency stop operation by the driver or the like, and burnout of the armature coil of the motor can be effectively prevented.

(2) The relay provided in the power supply circuit may be an ordinary relay, and it is inexpensive and highly reliable because there is no need to use special parts such as a relay with a timer.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram showing an embodiment of the present invention. In the figure, 12 is a limit switch, 13 is a motor, 15 is a power supply, 16 is a relay, 21 is a starter switch, 23,
Reference numeral 24 is a contact piece (output terminal), 27 is a relay contact, 28 is a relay winding, and 29 is an AC generator.

Claims (1)

[Scope of utility model registration request] 1. A motor for driving a shut-off element such as fuel or air, and a rotating portion that rotates in synchronization with the motor. Limit switch that selectively blocks conduction, and O
An automatic stop apparatus for an internal combustion engine, comprising: a starter switch for switching and connecting one of the output terminals to the motor according to N or OFF, and providing a relay contact in a power supply path to the motor, The relay coil of the contact is connected to the AC generator, and the starter switch is connected to the power source through the terminal of the starter switch that is turned on and off in conjunction with the starter switch.
An automatic stop device for an internal combustion engine, characterized in that the power supply to the motor is cut off when the engine is set to FF and the engine is brought to an emergency stop.