JPH0625544B2 - Engine stop device for diesel engine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an engine stop device for a diesel engine, and more particularly, by operating an intake cutoff valve with an electric motor with internal contacts formed so as to be stopped in two positions. The present invention relates to an engine stop device that stops an engine.

<< Prior Art >> An electric motor with an internal contact is used to operate an intake cutoff valve to cut off fuel air flowing into a combustion chamber to stop a diesel engine, which is conventionally shown in, for example, Japanese Patent Publication No. 54-43128. There was something that was done.

This includes a circuit changeover switch that operates in conjunction with a key switch, and a rotary limit switch that rotates in synchronization with the motor output shaft and stops rotation every 180 degrees of rotation in the electric motor drive circuit. However, the intake cutoff valve is opened and closed by operating the key switch.

<Problems to be solved> In the above conventional engine stop device, the key switch is set to OF
By operating to the F position, that is, the engine stop position, the intake cutoff valve is configured to be held in the closed posture after being actuated to the intake passage closing side, and at the other operation positions of the key switch. After operating the open side,
Since it is configured to hold the intake passage open posture,
The intake cutoff valve remains closed while the engine is stopped. Therefore, when the intake cutoff valve freezes in the cold season or the battery is in an over-discharged state, the intake cutoff valve does not open at the time of starting and there is a problem that the engine cannot be started.

<< Means for Solving Problems >> The present invention solves the above problems and allows the engine to be reliably stopped by a simple operation, but the intake cutoff valve is fully opened after the engine is stopped. To ensure a smooth start for the next start.
In an engine stop device configured to stop an engine by operating an intake cutoff valve arranged in an intake passage of a diesel engine with an electric motor, two circuits are selectively opened in conjunction with rotation of the electric motor. A selector switch and a circuit selector switch that is selectively controlled by a relay to close two circuits are placed in series in the power supply path from the battery of the electric motor, and the selector switch rotates 180 degrees of the motor output shaft. Each circuit is configured to open alternately, and a relay for switching control of the circuit changeover switch and an engine stop operation switch are connected via the stop control switch, and this stop control switch is connected to a timer, a rotation detector, etc. It is characterized in that it is configured to be opened by a command from the engine stop confirmation means.

<< Operation >> In the present invention, a selection switch that selectively opens two circuits in conjunction with the rotation of the electric motor, and a circuit selection switch that is selectively controlled by a relay to selectively close two circuits Are arranged in series in the electric motor power supply path, and the selection switch is configured such that two circuits are alternately opened every 180 degrees rotation of the motor output shaft, and a relay and an engine stop operation switch for switching control of the circuit changeover switch. Is connected via a stop control switch, and this stop control switch is configured to open by a command from an engine stop confirmation means such as a timer or a rotation speed detector. The circuit is turned on, the relay operates, the circuit changeover switch is switched, the electric motor operates, and the intake cutoff valve operates toward the intake passage cutoff side. Then, when the output shaft of the electric motor rotates 180 degrees, the selection switch opens the circuit to the electric motor in conjunction with it,
The intake cutoff valve is held in the fully closed position, and the engine stops. When the stop confirmation means confirms that the engine has stopped and issues a command, the stop control switch cuts off the circuit to the relay by the command, and the circuit changeover switch is switched. Then, the circuit conducted by the selection switch is energized, so that the electric motor operates to operate the intake cutoff valve to the intake passage opening side. As a result, the intake passage is kept open while the engine is stopped.

<< Embodiment >> A drawing is a schematic block diagram showing an embodiment of the present invention.

In the figure, reference numeral (1) is the intake passage of the diesel engine,
(2) is an intake cutoff valve. The intake cutoff valve (2) is linked to an electric motor (3) with a reducer by a power transmission mechanism (4). The power transmission mechanism (4) is a motion conversion mechanism consisting of an arm (6) fixed to the output shaft (5) of the electric motor (3) and a moving member (7).
(8) and a release wire arranged between the moving member (7) of the motion conversion mechanism (8) and the input arm (9) of the intake cutoff valve (2).
It is composed of (10).

The electric motor (3) is directly connected to the battery (12) through the power supply path (11), and the power supply path (11) is connected with the rotation of the electric motor (3) and the selection switch (13 ) And a circuit changeover switch (15) for switching control of the circuit by the relay (14) are arranged in series.

The selection switch (13) is a movable contact piece (16) that rotates in synchronization with the output shaft (5) of the electric motor (3), and two annular contact plates (17) (18) arranged concentrically. The two annular contact plates (17) and (18) are arranged such that their open portions are 180 degrees out of phase with each other.

The circuit changeover switch (15) is designed to be controlled by the relay (14), and the first contact (19) of this circuit changeover switch (15) is the outer annular contact plate (17) of the selection switch (13). The second contact (20) is the inner ring contact plate of the selection switch (13).
Connected to (18).

The relay (14) for switching control of the circuit changeover switch (15) is an engine stop control switch (24) controlled by a timer (22) to an engine stop operation switch (21) consisting of a key switch.
Connected through. This engine stop control switch (24) is a timer that closes the circuit to the relay (14) when the engine stop operation switch (21) is stopped, and starts the timekeeping operation when the engine stop operation switch (21) is stopped. When the time set in (22) elapses, the relay (1
The circuit to 4) is configured to be switched off. The set time of the timer (22) is set by predicting the time until the engine completely stops. In this example, the timer (24) serves as the engine stop confirmation means (S).

Reference numeral (25) in the figure denotes an electromagnetic fuel cutoff operation tool arranged in parallel with the relay (14).

In the engine stop device having the above-described configuration, when the engine stop operation switch (21) is operated, the fuel stop control switch (24) becomes conductive, and the fuel cutoff operation tool (25) and the relay
Supply (14). This actuates the fuel to shut off the fuel, and the relay (14) is switched to switch the circuit changeover switch (15) from the first contact conducting state to the second contact conducting state. Then, the current from the battery (12) is
It is supplied to the electric motor (3) through the movable contact piece (16) of (13), the inner annular contact plate (18), and the second contact (20) of the circuit changeover switch (15), and the intake cutoff valve (2). To close.

When the movable contact piece (16) reaches the position where the intake cutoff valve (2) is fully closed, that is, the position where the output shaft (5) of the electric motor (3) is rotated 180 degrees, the selection switch (13) The movable contact piece (16) is located at the open portion of the inner annular contact plate (18), and the circuit is cut off. At this time, in the selection switch (13), the movable contact plate (16) and the outer annular contact plate (17) are in a conductive state, but the circuit changeover switch ( Since the first contact (19) of 15) is in a non-conducting state, electric power is not supplied to the electric motor (3).
Therefore, the intake cutoff valve (2) is held in the fully closed position. This ensures that the engine is stopped by both intake cutoff and fuel cutoff. As described above, if the engine stop due to the fuel cutoff is performed together with the engine stop due to the intake air cutoff, the fuel is not injected during the engine stop operation, so that black smoke is not generated at the next start.

When a certain period of time elapses after the engine stop operation switch (21) is operated, the engine stop control switch (24) is opened by a command from the timer (22), the power supply to the relay (14) is stopped, and the fuel cutoff operation is performed. Turn off the power supply to the tool (25). Then, the circuit changeover switch (15) is switched from the second contact connection state to the first contact connection state. This allows the battery (1
2) and electric motor (3) are movable contact piece (16), outer ring contact plate (1
7), conduction is established through the first contact (19), the electric motor (3) is rotated, and the intake cutoff valve (2) is operated to the passage opening side. And, the position where the intake cutoff valve (2) is fully opened, that is, the output shaft (5) of the motor (3) is 1
When rotated by 80 degrees, the movable contact piece (16) will move to the outer annular contact plate (17).
It will be located at the open part of and the energization will be stopped. At this time, the inner annular contact plate (18) and the movable contact piece (16) are in a conductive state, but the second contact (20) is in a non-conductive state, so the electric motor (3) is connected to the output shaft (5 ) Will stop at the position rotated by 180 degrees.

As a result, after the engine is stopped, both the fuel cutoff operation tool (25) and the intake cutoff valve (2) are returned to the operating position. Therefore, the next start can be easily performed without any trouble.

In the above embodiment, the electric motor operating timing for operating the intake cutoff valve (2) to the open side is set according to the set time of the timer, but the engine speed is detected by the lubricating oil pressure or the generated voltage, The engine stop control switch (24) may be controlled to be switched by directly detecting the engine speed and confirming the engine stop state by detecting the engine speed. In this case, the engine speed detector is the engine stop confirmation means (S).

<< Effects >> In the present invention, a selection switch that selectively opens two circuits in conjunction with the rotation of the electric motor, and a circuit selection switch that is selectively controlled by a relay to selectively close two circuits Are arranged in series in the electric motor power supply path, and the selection switch is configured such that two circuits are alternately opened every 180 degrees rotation of the motor output shaft, and a relay and an engine stop operation switch for switching control of the circuit changeover switch. And is connected via a stop control switch, and this stop control switch is configured to be opened by a command from an engine stop confirmation means such as a timer or a rotation speed detector, so when the engine stop operation switch is operated, When the electric motor rotates a certain amount and the intake cutoff valve closes the intake passage, and the engine stops, the electric motor rotates a certain amount again and opens the intake cutoff valve. Therefore, the intake passage is kept open while the engine is stopped. As a result, since the intake cutoff valve is in the open posture at the next start operation, the engine can be started even if the intake cutoff valve cannot be moved due to freezing or battery exhaustion.

The valve position holding force that holds the intake cutoff valve at the position after switching the valve between the open position and the closed position is the friction of the motor / reducer part in the electric motor with reducer and the motion conversion mechanism. Since a strong force is obtained by the force and each static inertial force, a strong valve opening operation spring is unnecessary.

Therefore, the electric force generated by the motor section of the electric motor with a reducer does not have to be subjected to the resistance of the above-mentioned unnecessary and powerful spring for valve opening operation. Because it is done, a small force is enough.

As a result, the electric motor can be small-sized and inexpensive with a small output.

Moreover, since the electric power consumption of the electric motor is very small, the electric power consumption of the battery is reduced and the battery is less likely to occur.

[Brief description of drawings]

The drawings are schematic configuration diagrams showing an embodiment of the present invention. 1 ... Intake passage, 2 ... Intake shutoff valve, 3 ... Electric motor,
5 ... Motor output shaft, 8 ... Motion conversion mechanism, 11 ... (3)
Power supply path, 12 ... Battery, 13 ... Selection switch, 14 ...
… Relay, 15 …… Circuit changeover switch, 21 …… Engine stop operation switch, 22 …… Timer, 24 …… Stop control switch, 25 …… Fuel cutoff operation tool, S …… Engine stop confirmation means.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Atsushi Yamaguchi 64 Ishizukitamachi, Sakai City, Osaka Prefecture Kubota Iron Works Co., Ltd.Sakai Factory (72) Inventor Yuzo Umeda 64, Ishizukitamachi, Sakai City, Osaka Prefecture In-house (56) Bibliographic references Sho 54-82828 (JP, U)

Claims (5)

[Claims] 1. An intake cutoff valve (2) is arranged in an intake passage (1) of a diesel engine, and the intake cutoff valve (2) is connected to an electric motor (3) with a reduction gear through a motion conversion mechanism (8). When connected, the intake motor shutoff valve (2) is controlled to open / close by the rotation of the electric motor (3), and the battery is operated by operating the engine stop operation switch (21).
In the engine stop device for a diesel engine, which is configured to shut off the intake passage (2) by operating the electric motor (3) with the electric power supplied from (12), the electric motor (3 ) The power supply path (11) from the battery (12) is controlled by the selection switch (13) that selectively opens two circuits in conjunction with the rotation of the electric motor (3) and the relay (14). The selection switch (15) that selectively closes the two circuits is arranged in series, and the selection switch (13) is opened alternately every two rotations of the motor output shaft (5) by 180 degrees. The relay (14) for switching control of the circuit changeover switch (15) and the engine stop operation switch (21) are connected via the stop control switch (24), and the stop control switch (24) is connected. A diesel engine characterized by being configured to open at the command of the engine stop confirmation means (S). Emissions of the engine stopping device. 2. An engine stop operation switch using a key switch
An engine stop device for a diesel engine according to claim 1, which constitutes (21). 3. The engine stopping device for a diesel engine according to claim 1 or 2, wherein a fuel cutoff operation tool (25) is arranged in parallel with the relay (14). 4. The engine stop confirmation means (S) is a timer (22).
The engine stopping device for a diesel engine according to any one of claims 1 to 3. 5. The engine stop device for a diesel engine according to claim 1, wherein the engine stop confirmation means (S) is an engine speed detector.