JPS62634A - Starting device for internal-combustion engine - Google Patents

Abstract

PURPOSE:To shorten a starting time of an engine, by a method wherein, after dropform fuel injected in a reactor is ignited, a ratio of fuel and air is controlled, and fuel concentration is increased to produce combustible gas. CONSTITUTION:Methanole and the like is injected through a fuel injection valve 14 into a reactor body 13, and dropform fuel is ignited by a glow plug 15. Thereafter, an amount of fuel and air fed through a fuel feed passage 29 and an air feed passage 17 is controlled, and fuel concentration is gradually increased. Combustible gas so produced is fed to the combustion of an engine through a feed passage 19. This enables sharp decrease of a starting time of an engine.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a starting device for an internal combustion engine, and for example, to a starting device for an internal combustion engine that uses alcohol fuel such as methanol.

<Prior art> Alcohol fuels such as methanol have poor ignition performance compared to gasoline, making it difficult to start at low temperatures.There are some systems that improve low-temperature startability by converting dialcohol fuel to hydrogen, etc. . Such a conventional example is shown in FIG. 3 (see Japanese Unexamined Patent Publication No. 113426/1983).

That is, methanol is supplied to the combustion device 2 via the first on-off valve 1, and the methanol is ignited and burned by the spark plug 3. Then, the reactor 4 is heated by the combustion operation of the combustion device 2, and the inside of the reactor 4 is raised to the reaction temperature of methanol. Thereafter, methanol is supplied to the reactor 4 through the on-off valve 5 of the cylinder 2 and converted into a flammable gas containing a large amount of hydrogen.The flammable gas is then supplied to the engine T through the vaporizer 6. This improves low-temperature startability.

Note that 8 is a battery and 9 is an engine switch.

<Problems to be solved by the invention> However, in such a conventional starting device,
Since the combustion device 2 and the reactor 4 are provided separately and the methanol fuel and combustion air are controlled respectively, the structure is complicated and the cost is high. Further, there was a problem in that it took time to heat the reactor 4 and raise it to the reaction temperature, and it took time to start the engine.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a starting device for an internal combustion engine that has a simple structure and can generate flammable gas in a short time.

Means for Solving the Problems> For this reason, the present invention provides a hollow reactor body that generates flammable gas, a fuel injection valve device that injects fuel into the reactor body, and a fuel injection valve device that injects fuel into the reactor body. an ignition device that ignites the fuel;
an air supply passage that supplies air into the reactor body; a flammable gas supply passage that supplies flammable gas generated within the reactor body to the engine; and a temperature sensor that detects the temperature of the flammable gas. and a control means for controlling the ratio of fuel and air supplied into the reactor body in order to increase the fuel concentration as the detected temperature increases and maintain the flammable gas temperature substantially constant; We prepared the following.

<Function> In this way, after the injected droplet-shaped fuel is ignited in a short time, the supply ratio of fuel and air is controlled according to the flammable gas temperature, and the flammable gas is ignited in a short time with a simple structure. generated in time, thereby improving the starting performance of the engine.

<Example> An example of the present invention will be described below based on FIGS. 1 and 2.

In FIG. 1, a reactor 12 for converting methanol as a liquid fuel into a flammable gas containing hydrogen is provided near an intake manifold 11 of an engine (not shown).

A hollow reactor main body 13 is formed in this reactor 12, and a cylindrical member 13a is attached inside the reactor main body 1'3 to form a predetermined gap between it and the inner wall of the main body 13. . The reactor main body 13 is provided with a fuel injection valve 14 for injecting methanol into the cylindrical member 13&. Further, the reactor main body 13 is provided with a glow plug 15 as an ignition device for igniting droplet-shaped methanol injected from the fuel injection valve 14. An air supply passage 17 for introducing intake air upstream of the intake throttle valve 16 is provided in the cylindrical member 13a, and a diaphragm type air flow control valve 18 is interposed in the air supply passage 17.

Further, a flammable gas supply passage 19 is provided which communicates with the upper space inside the reactor main body 13 and the interior space of the intake manifold 11 downstream of the intake throttle valve 11. Gas temperature sensor 2 that detects temperature
G is provided. A cooling water passage 21 through which engine cooling water flows is formed in the outer wall of the reactor main body 13, and a water temperature sensor 22 for detecting the temperature of the cooling water is provided in the cooling water passage 21. The water temperature sensor 22 is made of bimetal or the like, and turns on when the cooling water temperature is below a predetermined value (for example, 60°C), and turns on when the coolant temperature exceeds a predetermined value, that is, after warm-up is completed.
It is configured to be a FF.

One terminal of the water temperature sensor 22 is connected to a child terminal of a battery 24 via an ignition switch 23, and the other terminal of the water temperature sensor 22 is connected to one end of a relay coil 25m of a normally open first relay 25. Relay coil 251
The other end of L is connected to the collector terminal of a common emitter transistor 2T provided in the control device 26. A child terminal of the battery 24 is connected to one end of the glow plug 15 via a relay contact 25b of the first relay 25, and the other end of the glow plug 15 is grounded.

Further, one end of the relay coil 28a of the normally open self-holding type second relay 28 provided in the control device 26 is connected to the child terminal of the battery 24 via the starter motor switch 29, and the other end of the relay coil 28m is Grounded. One end of the relay contact 28b of the second relay 28 is connected to one end of the relay coil 25& of the first relay 25, and the other end of the relay contact 28b is connected to the fuel supply passage 29 that supplies methanol to the fuel injection valve 14. Electromagnetic on-off valve 3
Connected to the 0 input terminal. Also, the second relay 2B
The other end of the relay coil 28a is grounded via a resistor 31 and a Zener diode 32.
The power V- terminal of No. 2 is connected to one terminal of the control circuit 33, and a constant voltage is applied to the + terminal of the control circuit 33.

Further, the other terminal of the control circuit 33 is connected to the gas temperature sensor 2.
An output voltage of 0 is applied. This gas temperature sensor 2
0 is configured such that the output voltage increases as the temperature of the combustible gas increases.

The output voltage of the control circuit 33 is applied to the servo pulp 35 via the amplifier 34, and the servo valve 35 controls the operating negative pressure of the diaphragm air flow control valve 18 according to the applied output voltage. do.

36 is a diode, and 3T is an inverting amplifier.Next, the operation will be explained according to the time chart shown in FIG.

When the engine starts, the coolant temperature sensor 22 is on because the coolant temperature is low, so turn on the ignition switch 23.
Then, a voltage is applied from the battery 24 to the relay coil 25m of the first relay 25 via the water temperature sensor 22. At this time, since the temperature in the combustible gas supply passage 18 is low and the output voltage of the gas temperature sensor 20 is low, this voltage is inverted by the inversion amplifier 3T and the pace current of the transistor 2T increases. This turns on the transistor 2T and excites the relay coil 25m of the first relay 25, thereby closing the relay contact 25b. and glow plug 1
5 is supplied with electricity from the battery 24, and the glow plug 15 is preheated.

When the starter motor switch 29 starts ONL cranking, the relay coil 28m of the second relay 2B is energized via the starter motor switch 29, the relay coil 28m is energized, and the relay contact 28b is closed. Accordingly, the electromagnetic on-off valve 30 is energized from the battery 24 via the water temperature sensor 22 and the relay contact 28b, and the electromagnetic on-off valve 30 opens. Therefore, methanol is supplied to the fuel injection valve 14, and a constant amount of methanol is injected and supplied from the fuel injection valve 14 into the cylindrical member 13a.

Also, at the same time as the electromagnetic on-off valve 30 is energized, the control circuit 3 is supplied from the battery 24 via the relay coil 28 and the resistor 31.
A constant voltage is applied to the child terminal of No.3.

At this time, since the output voltage of the gas temperature sensor 26 is low, the output of the control circuit 33 is large and the servo valve 35 is fully opened. With this, diaphragm type air flow control valve 1
8, the air flow control valve 18 is fully opened.

Therefore, droplets of methanol and air are supplied into the cylindrical member 13a, and the mixture thereof is ignited by the glow plug 15, causing the temperature inside the reactor body 13 to rise. When this heated combustible gas flows into the combustible gas supply passage 19, the output voltage of the gas temperature sensor 20 increases as the gas temperature increases. And gas temperature sensor 2
When the zero output voltage reaches a predetermined value, the output of the inverting amplifier 37 becomes L#, the transistor 27 is turned off, the relay contact 25 & of the first relay 25 opens, and the energization to the glow plug 15 is stopped.

Furthermore, when the output voltage of the gas temperature sensor 20 increases, the output voltage of the control circuit 33 gradually decreases, and the servo pulp 35
The output to is reduced. Air flow control valve 18
Since the operating negative pressure is small, the amount of air supplied into the cylindrical member 13a through the air flow control valve 18 is reduced. Therefore, the methanol concentration within the cylindrical member 13& increases, and the hydrogen concentration in the generated combustible gas increases. In this way, the air flow rate is controlled so that the temperature of the flammable gas is maintained at a temperature where the concentration of combustible gas containing sufficient hydrogen is achieved.

The generated flammable gas is then transferred to the intake manifold 11.
is supplied to the engine via the engine and the engine starts.

Furthermore, since the cooling water temperature is low immediately after the engine starts, the water temperature switch 22 is maintained in the ON state, so the relay contact 2
The relay coil 281 is energized from the relay coil 281 through the diode 36, and the relay contact 28b is closed. A constant voltage is applied to the control circuit 33 via the water temperature switch 22 and the relay contact 28b of the second relay 2B, and fuel and air are supplied to the cylindrical member 13&. As a result, flammable gas is supplied to the engine immediately after the engine is started, thereby stabilizing engine operation during warm-up. Then, when the cooling water temperature rises due to completion of warm-up, the water temperature switch 20 is turned off, and the power supply to the second relay 28 and relay 28 & is stopped, and the relay contact 28 is turned off.
b opens. As a result, the power supply to the electromagnetic on-off valve 30 is stopped, the injection operation of the fuel injection valve 14 is stopped, and the constant voltage application to the control circuit 33 is stopped, so that the servo valve 3
5 is stopped, and the air supply operation is stopped.

As explained above, after the droplet-shaped methanol injected into the cylindrical member 138 is ignited, the air supply amount is controlled to maintain the temperature of the generated combustible gas substantially constant, so that the combustible gas containing sufficient hydrogen can be heated. Since flammable gas is supplied to the engine, flammable gas can be generated in a short time after droplets of methanol are ignited in a short time, and the engine can be started in a short time. In addition, flammable gas can be generated without particularly providing a combustion device as in the conventional case, and the structure is extremely simple and cost can be reduced.

Furthermore, since the cooling water is made to pass through the reactor main body 13 and outside, the cooling water is heated by the reaction heat, so that the warm-up time can be significantly shortened.

In this embodiment, the methanol concentration was increased by changing the air supply amount, but the methanol injection amount may be controlled to be changed instead.

<Effects of the Invention> As explained above, the present invention generates flammable gas by igniting the injected droplet fuel and then controlling the ratio of fuel and air to increase the fuel concentration. Combustible gas can be generated in a short time, thereby greatly reducing engine starting time. Furthermore, flammable gas can be generated without particularly providing a conventional combustion device, and the device can be simplified, thereby reducing costs.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, FIG. 2 is a time chart of the same, and FIG. 3 is a block diagram showing a conventional example of a starting device for an internal combustion engine. 12... Reactor 13... Reactor main body 14.
・・Fuel injection valve 15・Glow plug 1T・
...Air supply passage 18...Air flow control valve 1
9...Flammable gas supply passage 20...Gas temperature switch 26...Control device patent applicant Nissan Motor Co., Ltd. agent Patent attorney Fujio Sasashima Figure 2 Figure 3

Claims (1)

[Claims] A starting device for an internal combustion engine that converts liquid fuel into flammable gas and supplies the flammable gas to the engine during startup includes a hollow reactor body that generates the flammable gas, and a liquid fuel inside the reactor body. an ignition device that ignites the injected fuel; an air supply device that supplies air into the reactor body; a flammable gas supply passageway for supplying the flammable gas to the combustible gas; a temperature sensor for detecting the temperature of the flammable gas; 1. A starting device for an internal combustion engine, comprising: a control device that controls the ratio of fuel and air supplied into the engine body.