JPS6018827B2 - Internal combustion engine restart device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for facilitating the restart of an internal heat engine.

When an internal heat engine continues to operate and then stops, the ambient temperature around the engine rises, and gasoline evaporation gas is generated in the intake manifold due to the vaporization of the fuel adhering to the inner wall of the engine. The evaporative gas from the float chamber and the evaporative gas from the outlet pipe of the fuel tank and canister flow in and accumulate.

Therefore, when the engine is restarted next time, these evaporated gases are inhaled all at once, and the fuel from the carburetor is added to this, making the intake air temperature extremely rich when the engine is restarted. Not only does it take a considerable amount of time to start the engine, but more harmful gases such as HC are generated. Therefore, as the prior art,
No. 3 proposes to prevent the intake air temperature to the engine from becoming too rich when the engine is started by sucking new air into the intake manifold through an intake valve that is linked to the start of the engine. However, the intake valve in this prior art opens when the engine is started and closes after an appropriate period of time, and the suction of new air starts and stops rapidly. Since the intake of new air suddenly stops at the same time as the engine starts, the air-fuel ratio of the intake air intake air fluctuates rapidly, making it difficult to smoothly control the air-fuel ratio to an appropriate value when starting the engine. Met. In the present invention, when new air is sucked into the intake manifold through the intake valve when starting the engine, the intake valve repeatedly opens and closes, that is, the opening operation of the intake valve is intermittently performed when starting the engine. With this configuration, rapid fluctuations in the air-fuel ratio of the intake air temperature due to the intake of fresh air are reduced.

Next, an example of the present invention will be explained with reference to a drawing. In the drawing, 1 is attached to an engine (not shown).
1 shows the carburetors attached to the intake manifold 1, and an air cleaner 4 having a filter cleaner 3 is connected to the upstream side of the carburetor 2.

The manifold 1 is provided with an air intake port 5, and in the air intake passage 7 connecting this to the clean side of the air cleaner 4 or the air intake filter 6, there is a check valve 8 and an electromagnetic air intake valve 9 of the energized open type. are provided in series, and the suction valve 9
The operating solenoid 10 is connected to a capacitor 12, a diode I3. A programmer full union transistor 14 (hereinafter simply referred to as PUT), a transistor 15, a variable resistor 16, and five resistors 17, 18, 19,
20 and 21 are provided in the intermittent circuit 11 formed by loosening them together, and a circuit 23 connecting the intermittent circuit 11 and the battery 22.
Inside, if you turn the engine key on the engine to ignition ON and then to star ○N, it will turn ON to star ○F.
There is a switch 24 that turns OFF when the temperature is F, and a temperature switch 25 that turns OFF when these temperatures are related to the temperature of the engine carburetor or the engine room, such as engine cooling water temperature, and become evaporative gas accumulated in the intake manifold. and are provided in series. Then, when starting the engine, when the engine key of the engine is turned to the ignition ON' and then to the star ignition N, the switch 24 is turned ON in conjunction with this, but in this case, the temperature of the engine or the engine room is low. When there is no accumulation of evaporative gas in the intake manifold 1, the temperature switch 25 is OFF, so no current flows through the intermittent circuit 11, and therefore the intake valve 9 does not open.

However, when the temperature of the engine, carburetor, or engine room is high and evaporative gas accumulates in the intake manifold, the temperature switch 25 is turned ON, so the switch is linked to the start control. 24 turns on, current flows through the intermittent circuit 11. In response to this, the capacitor 12 is gradually charged through the resistors 16 and 17, but the current at this time is so weak that it does not act on the solenoid 10'.

When the charging of the capacitor 12 progresses and the anode potential of the PUT 14 exceeds a certain value determined by the resistors 19 and 20, the PUT 14 turns on. Transistor 1 accordingly
Since the base potential of solenoid 5 increases, the transistor 15 turns on, and a large current flows through the solenoid 10', driving the suction valve 9. - On the other hand, since the capacitor 12 discharges through the PUT 14, the anode potential of the PUT 14 also decreases. When the anode potential drops to a certain value, the PUT 14 turns on, returning to its initial state, and the action of the solenoid 10 is also released. Since the solenoid 10 operates intermittently in a constant cycle, the intake valve 9 also repeats opening and closing in this constant cycle, and new air is intermittently sucked into the intake manifold 1, causing the air to accumulate in the intake manifold 1. It dilutes the evaporated gas and corrects the air/fuel ratio to an appropriate value, and when the engine starts, the star
When it is set, the switch 24 linked to this also becomes OFn,
The intermittent opening and closing of the intake valve 9 is stopped, and the intake of new air into the intake manifold 1 is stopped. In this case, the amount of fresh air sucked into the intake manifold 1 per unit time can be arbitrarily increased or decreased depending on the number of opening/closing cycles of the intake valve 9 or the time the intake valve is closed during one cycle. 12 capacitances, 1 variable resistance
6 etc. can be set to the optimal value, and
It goes without saying that the air suction valve 9 may be of a closed type.

As described above, the present invention improves the air intake temperature in the intake manifold by intermittently opening and closing the intake valve in the air intake passage connected to the intake manifold, which also connects the carburetor and the engine. Since it corrects the fuel ratio, it is possible to reliably prevent sudden changes in the air-fuel ratio caused by the sudden start and stop of intake of new air into the intake manifold. This allows the air-fuel ratio to be smoothly controlled to an appropriate value.

Therefore, according to the present invention, it is possible to reliably start the engine from a high temperature state in a short time, and improve the startability of the engine at high temperatures. It has the effect of reliably reducing the

[Brief explanation of drawings]

The drawings show an embodiment of the invention, FIG. 1 is a diagram of the device, FIG.
The figure is a circuit diagram. DESCRIPTION OF SYMBOLS 1... Intake manifold, 2... Carburizer, 7... Air intake passage, 9... Intake valve, 10... Solenoid, 1
1... Intermittent circuit, 24... Switch, 25... Temperature switch. Third figure of blind screen

Claims (1)

[Claims] 1. An air intake passage is connected to the intake manifold that connects the carburetor and the engine, and an intake valve is installed in the air intake passage to open when the starter switch is turned on while the engine temperature is high. A restart device for an internal heat engine, characterized in that the suction valve is provided with means for intermittent opening operation of the suction valve.