JPS6136736Y2 - - Google Patents

Description

[Detailed description of the invention] This invention provides an emergency stop control that prevents malfunction of the emergency stop device in an engine equipped with an emergency stop device that stops the engine in an emergency according to the detection of the lubricating oil level in the engine oil pan. Regarding equipment.

In order to prevent the engine from seizing due to lack of lubricating oil, an emergency stop device is installed that detects the lubricating oil level in the oil pan and stops the engine directly or by issuing an alarm when the oil level drops below a set low level. I have something prepared.

However, in cold regions, the viscosity of the lubricating oil remains low for a while after startup, so it takes time for the lubricating oil fed from the oil pan into the cylinder block to circulate and return to the oil pan. As a result, the lubricating oil level in the oil pan temporarily drops below the level detected by the emergency stop device, causing the emergency stop device to operate and stop the engine even though it is in a normal state. I had to put it away.

Therefore, if a delay mechanism is provided that delays the operation of the emergency stop device until the oil level in the oil pan recovers as the lubricating oil temperature rises after a predetermined period of time has elapsed after startup, it is possible to prevent the engine from stopping under normal conditions. .

However, if such a delay mechanism is provided, if the lubricating oil is insufficient to begin with, the engine will be operated with insufficient lubricating oil until the emergency stop device starts operating, which is an undesirable situation for the engine. occurs.

The present invention was developed in view of the conventional situation, and includes an emergency stop device that detects and activates when the lubricating oil level in the oil pan is below a set level after the engine has started, and when the engine is stopped. detects the oil level in the oil pan, and when the oil level exceeds the set level when the engine is stopped, the emergency stop device is activated with a delay of a set time after the engine starts, and when it is below the set level, the emergency stop device is activated immediately after the engine starts. To provide an emergency stop control prevention device for an engine which prevents the engine from stopping in a normal state as a configuration for activating a stopping device, and also enables the engine to be reliably stopped when lubricating oil is insufficient.

The present invention will be explained below based on illustrated embodiments. In FIGS. 1 to 4 showing one embodiment, the lubricating oil in the engine oil pan is normally open and closes when the lubricating oil falls below a first set level, which is set based on the oil level before starting the engine. A first oil level detection switch 1 and a normally open second oil level detection switch 2 are provided, which are closed when the oil level falls below a second set level, which is set based on the oil level after engine startup. .

The first oil level detection switch 1 is connected to a battery 6 through a normally closed contact 3a of a relay 3, a coil 4a of a relay 4, and a main switch 5 in series. The second oil level detection switch 2 is connected to the output terminal of the generator 9 in series with the coil 7a of the relay 7 and the normally closed contact 8a of the relay 8.

The coil 3b of the relay 3 is connected to the output terminal of the generator 9 via the input terminal of the timer switch 10 in series. Said timer switch 1
The switch terminal 0 is connected to the normally closed contact 11a of the relay 11 via the coil 8b of the relay 8 in series. The coil 11b of the relay 11 is connected to a switch terminal of a timer switch 12,
The input terminal of the timer switch 12 is connected to the relay 4.
It is connected to the battery 6 through the normally closed contact 4b of the main switch 5 and the main switch 5 in series.

Further, a solenoid 13 serving as an engine stop driving device that operates when energized cuts off fuel injection and forcibly stops the engine is connected to the output terminal of the generator 9 through the normally closed contact 7b of the relay 7 in series. ing.

Next, the operation of this configuration will be explained.

First, before starting the engine, if the lubricating oil level in the oil pan exceeds the first setting level L1 and there is sufficient lubricating oil, the first oil level detection switch 1 and the second oil level detection switch 2 are activated. They have been developed together. In this state, the main switch 5 is closed, and a starter (not shown) connected to the main switch 5 is activated to perform cranking. As a result, when the engine starts and reaches a predetermined rotational speed, a voltage is generated at the output terminal of the generator 9, and the relay 3
is energized and the contact 3a is opened. Therefore, after this, the lubricating oil level in the oil pan decreases due to lubricating oil being supplied to the cylinder block, and the first oil level detection switch 1 is closed. Since at least one of them is open, the relay 4 is not energized and the contact 4b is kept open. Therefore, no power is input to the timer switch 12 and its switch terminal remains open, so that the relay 11 is not energized and its contact 11a remains closed. As a result, after the voltage is generated from the generator 9, the relay 8 is energized for the same set time via the timer switch ₁₀ , which is closed for the set time t1, and the closed contact 11a, and the contact 8a is opened. Therefore, even if the second oil level detection switch 2 is temporarily closed due to the temporary drop in the lubricating oil level while the contact 8a is opened for the set time _t1 , Switch 2 and contact 8a
As a result of at least one of the relays being opened, the relay 7 is not energized and the contact 7b is held open, so that the solenoid 13 does not operate, and it is possible to reliably prevent the engine from stopping due to malfunction. In addition, in an emergency when the oil level drops to below the second set level _L2 for some reason after the timer switch 10 is opened after the set time, the second set level L2 is opened along with the contact 8a.
The oil level detection switch 2 is closed and the solenoid 13
is activated and the engine can be stopped.

The contact opening/closing states of each device during such operation are as shown in FIG. 3, and the system returns to its initial state after the engine is stopped.

Next, if there is already a shortage of lubricating oil before starting the engine and the lubricating oil level in the oil pan is below the first setting level L1, the first oil level detection switch 1 is activated.
detects this and is closed. When the main switch 5 is closed in this state, the relay 4 is energized via the normally closed contact 3a and the switch 1, and the contact 4b is closed. Therefore, power is input to the timer switch 12, and the switch 12 is closed for the set time _t2 , so that the relay 11 is energized and the contact 11a is opened for the same set time _t2 . Therefore, relay 8 is contact 1
1a and at least one of the timer switch 10 is opened and is not energized, and its contact 8a
is kept closed. Therefore, the oil level, which was below the first set level L1 before starting, reaches the second set level L within the set time _t1 due to engine startup.
2 and the second oil level detection switch 2 is closed, the relay 7 is energized and the contact 7b is closed, so that the solenoid 13 is activated and the engine can be reliably stopped.

The contact opening/closing states of each device during such operation are as shown in FIG. 4, and the same returns to the initial state when the engine is stopped.

In this way, if a sufficient amount of lubricating oil is secured before starting the engine, it is possible to prevent the engine from stopping due to false detection of a temporary drop in the oil level immediately after starting. When there is a shortage, the engine can be stopped quickly.

The same function can be obtained by connecting a flip-flop circuit in place of the timer switch 12, which is held closed from the moment the contact 4b is closed until the main switch 5 is opened, and the rest are opened.

FIG. 5 shows a second embodiment of the present invention. To explain only the components that are different from the circuit of the previous embodiment, a relay 21 with a normally open contact 21a is provided in place of the relay 8, and a timer switch is provided. 10
Timer switch 22 and relay 11 installed in place of
The coil 21a of the relay 21 is connected in parallel with the normally open contact 23a of the relay 23 provided instead of
, timer switch 22, contact 23a and relay 3
It is connected to the output terminal of the generator 9 via the coil 3b.

The timer switch 22 is the generator 9.
After a set time _t1 has elapsed after voltage generation, the switch is switched from open to closed, and when the generator 9 stops, the switch is opened again.

Therefore, when the oil level before starting exceeds the first set level L1, the contact 23 of the relay 23 is opened because the first oil level detection switch 1 is open.
Since a is open, contact 21 of relay 21
a is closed only while the timer switch 22 is closed.

Therefore, even if the second oil level detection switch 2 is closed due to a temporary drop in the oil level during the set time _t1 when the timer switch 22 and contact 21a are open after voltage is generated from the generator 9, the relay 7 is not energized and the contact 7b remains open, so it is possible to prevent the engine from stopping due to the operation of the solenoid 13. In addition, in an emergency situation where the oil level drops to below the second set level L2 for some reason after the oil level has recovered after the set time _t1 has elapsed, the contact 21a is closed together with the timer switch 22, so the second As in the previous embodiment, the solenoid 13 is energized and activated when the oil level detection switch 2 is closed, and the engine can be stopped without any trouble. FIG. 6 shows the open and closed states of the contacts of each device during such operation.

On the other hand, when the oil level is below the first set level before starting the engine, the relay 4 is energized by closing the first oil level detection switch 1 and the contact 4b is closed, so the timer switch 12 is activated. By energizing for a set time and closing the switch 12 during this time, the contact 23a of the relay 23 is closed for the same set time. This timer switch 12 is set so that it overlaps with the switch 22 and remains closed for a while after the timer switch 22 is closed after the output voltage from the generator 9 is generated. Therefore, the relay 21 is kept closed by closing at least one of the timer switch 22 and the contact 23a until the engine stops after the voltage is generated from the generator 9.
By closing the oil level detection switch 2, the solenoid motor 13 is operated and the engine can be stopped quickly. The open/close states of the contacts of each device during such operation are as shown in FIG.

As explained above, according to the present invention, if there is a sufficient amount of lubricating oil before starting the engine, by delaying the operation of the oil level detection type emergency stop device after starting for a predetermined period, This prevents the engine from stopping due to a drop in the surface, and on the other hand, if the amount of lubricant is already insufficient before starting, the emergency stop device can be activated immediately to stop the engine, based on the actual amount of lubricant. This provides highly accurate functions and greatly increases practicality.

[Brief explanation of drawings]

Figure 1 is a circuit diagram showing one embodiment of the present invention;
The figure shows the state inside the oil pan in this embodiment, Figure 3 shows the operating state of each device in the same embodiment when the oil level before startup exceeds the set level, and Figure 4 shows the operating state of each device in the same embodiment. In the above embodiment, a diagram showing the operating state of each device when the oil level before startup is below the set level, FIG. 5 is a circuit diagram showing the second embodiment of the present invention, and FIG. 6 is the embodiment. Figure 7 shows the operating state of each device when the pre-start oil level exceeds the set level in the above example, and Figure 7 shows the operating state of each device when the pre-start oil level is below the set level in the same example. It is a diagram. 1...First oil level detection switch, 2...Second oil level detection switch, 3, 4, 7, 8, 11, 21, 2
3... Relay, 5... Main switch, 6... Battery, 9... Generator, 10, 12, 22
...Timer switch, 13...Solenoid.

Claims (1)

[Scope of utility model registration request] An emergency stop means for stopping the engine when the lubricating oil level in the oil pan after starting the engine is below a set level, and when the lubricating oil level in the oil pan before starting the engine exceeds a set level for starting which is higher than the set level. and an operation timing control means for delaying the operation of the emergency stop means for a predetermined period of time after the engine is started and operating the emergency stop means immediately after the engine starts when the engine temperature is below the set level for starting. Emergency stop control device.