JPS5851262A - Fuel vaporization promoting apparatus for engine - Google Patents

Abstract

PURPOSE:To heat a riser section of an intake pipe promptly and to thereby improve the engine starting performance, by forming a riser heating water passage in the intake pipe, and communicating the passage with a water jacket for cooling an engine and a cooling water storing, heat-insulating tank. CONSTITUTION:In case of cold starting of an engine, changeover valves 7, 8 are shifted by a control unit 13 such that their ports 7b and 7c and ports 8b and 8c are respectively communicated with each toher. At the same time, a water pump 10 is set into operation and a changeover valve 9 is closed. Resultantly, the temperature of a riser section 2a can be raised by feeding cooling water kept at a relatively high temperature in a cooling water storing, heat-insulating tank 5 to a riser heating water passage 4. By thus promoting vaporization of fuel supplied from a carburetor 1, engine can be warmed up efficiently without causing misfiring. Subsequently, when the temperature of cooling water has become higher than a prescribed value, the valves 7, 8 are shifted such that their ports 7a-7c and 8a-8c are all communicated with each other. At the same time, operation of the water pump 10 is stopped and the changeover valve 9 is closed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for promoting vaporization of fuel supplied to an engine.

Conventionally, the outer wall surface of the lower live portion of the carburetor in the intake pipe that connects the carburetor and the engine is brought into contact with engine cooling water or exhaust gas, and the poorly vaporized fuel that collides with the heat ripe portion is completely heated and vaporized. It is. A vaporization promoting device using electric heating has also been proposed.

However, in such conventional fuel vaporization accelerators,
In particular, when heating with engine cooling water, during a cold start, the engine cooling water temperature is low and fuel vaporization cannot be promoted, and the live part temperature rises slowly. Therefore, liquid fuel is sucked into the engine, which makes warm-up of the engine difficult and causes a misfire. In addition, the addition due to exhaust gas is
The disadvantage is that during high-load operation, the temperature of the air-fuel mixture rises too much, resulting in a decrease in engine output. Further, a heat riser using an electrically heated heating element exhibits a good start-up, but has the disadvantage that it consumes a large amount of current, resulting in a large battery load.

The present invention was devised to solve the problems of the prior art as described above, and it promotes vaporization of fuel by instant heating of the riser part, and also significantly reduces the burden on the battery. The purpose is to provide an engine fuel vaporization accelerating device that improves startability and stabilizes engine rotation during startup.To this end, high-temperature engine cooling water during engine operation is stored in a heat insulating tank, and then cooled into cold water. The technical idea is to pass water through the live part of the intake pipe during and before starting, and its configuration is such that the riser heating passageway is entirely formed in the intake pipe that connects the carburetor and the engine. This is an engine fuel vaporization accelerator VC which is connected to both a cooling water storage section and an engine cooling water heat retention tank in the engine.

Embodiments of the present invention will be described with reference to all drawings.

FIG. 1 shows a first embodiment of the present invention. In the same figure, 1 is a carburetor, and 2 is an intake pipe which is fully connected to the carburetor 1 and the ennon 3. A portion 28 of the intake pipe 2 immediately below the carburetor 1 is a live portion, and its outer wall surface is heated by hot water. Reference numeral 5 denotes an engine cooling water heat retention tank, which is formed of a hot water tank 5a and a heat insulation +*sb made of a solid insulation material or a vacuum layer, and stores all the heat of the high temperature engine cooling water. engine 3
Engine cooling returns from the cooling water storage section (water jacket, etc.) inside to the cooling water storage section in Ennon 3 via piping 6gs switching valve 7, piping 5a, live heating water passage, piping 6tx switching valve 8, and piping 6h. A water flow circuit is formed that heats the live portion with water. In addition, a pipe 6b branched from the switching valve 7 is connected to the engine cooling water heat retention tank 5, and the piping 6b
c, water pump 10, switching valve 8 via pipe 16d
It is connected to a more branched pipe 6h. In addition, a water pump 7'I is connected between the piping 6e and the piping 6d via a switching valve 9.
A bypass path 61 of O is formed. A heat retention water temperature detector 11 is attached to the engine coolant heat retention tank 5, and an engine coolant temperature detector 12 is attached to the coolant storage portion in the engine 3, respectively. The output signals of the thermal insulation water temperature detector 11 and the engine cooling water temperature detector 12 are applied to the control unit 13,
The output signal of the control section 13 is applied to the switching valves 7, 8, 9 and the water pump 10. Note that 14 is a switch, and 15 is a power source.

The operation of the first embodiment configured as described above will be explained.

The control operation by the control unit 13 is such that when the temperature detected by the insulating water temperature detector 11 is higher than the temperature detected by the engine cooling water temperature detector 12, the control operation of the switching valve 7 is performed.
a is closed, ports 7b and 7c are communicated with each other, and port 8a of the switching valve 8 is closed, and ports 8b and 8c are communicated with each other.
The two are connected.

Further, the switching valve 9 is closed, and the water pump 7610 is operated to supply water. In this way, a first water circulation circuit is formed that circulates between the engine cooling water heat retention tank 5 and the live heating water passage.

On the other hand, when the engine cooling water temperature is higher than the insulating water temperature, ports 7a, 7b, and 7c of switching valve 7 are all in communication, and ports 8a, 8b, and 8c of switching valve 8 are also all in communication. Also,
The water pump 10 is stopped, the switching valve 9 is opened, and the bypass passage 61 is opened. In this way, the cooling water storage section in the engine 3 and the second water passage circuit in which the live heating water passage 4 and the engine cooling water heat retention tank 5 flow and circulate water in parallel to the cooling water storage section. is formed.

The function of each part under actual operating conditions will be explained.

Immediately after a cold start of the engine 3, the engine cooling water temperature is extremely low, so even if this cooling water is passed through the heating water passage, the temperature of the live portion 2a hardly increases. For this reason, most of the poorly vaporized fuel supplied from the carburetor L is in the live section 2.
a, it is inhaled into the engine 3 without being vaporized, causing a misfire.

At this time, since the cooling water in the engine cooling water heat retention tank 5 is sufficiently high temperature, the above-mentioned first water passage is connected immediately before or immediately after the engine starts, and the cooling water at the pan temperature flows into the live heating water passage 4. Water is passed through, and the temperature of the live section 2a rises. Therefore, the fuel supplied from the carburetor 1 is accelerated to vaporize in the live section 2a and is inhaled into the engine 3, so warm-up is better and misfires do not occur compared to when the fuel is inhaled in liquid form. .

Next, during warm-up of the engine 3, when the engine cooling water temperature becomes higher than the temperature of the heat-retaining water, the aforementioned second water flow circuit is opened. At this time, engine cooling water is fed through a water tank 7° (not shown) in the engine 3, branched off at a switching valve 7, and supplied to a live heating passageway 4 and an engine cooling water heat retention tank 5. At this time, the live heating passageway 4 continues to be heated, and one engine cooling water heat retention tank 5 stores cooling water at pot temperature in preparation for the next start.

As described above, the live portion 2a is constantly heated immediately before starting, promoting vaporization of the fuel, improving startability and eliminating breathiness immediately after starting or during acceleration.

A second embodiment of the present invention will be fully explained. Figure 2 shows the second embodiment of the present invention.
The entire embodiment is shown, and in the figure, from the engine cooling water heat retention tank 5 to the piping 19a1, the riser heating passageway 4, the piping 19b, the switching valve 16, the piping 19g1, the switching valve 17, the piping 19c1, the water pump f18, and the piping 19d'e. A water flow circuit returning to the engine cooling water heat retention tank 5 is formed, and piping 19eS19f from the switching valve 16, 17 is connected to a cooling water storage section in the engine 3, respectively. In this water flow circuit, when the temperature of the insulating hot water is higher than the temperature of the engine cooling water, the ports 16a and 16b of the switching valve 16 are communicated, and the port 16C is closed. Also, the port 17a of the switching valve 17,
17b is communicated, the port 17a is closed, and the water pump 7'18 is activated to supply water. Therefore, the heat-retaining hot water is supplied to the riser heating passageway 4, and the live section 2a is heated.

Next, as the engine warms up and the engine cooling water temperature becomes higher than the insulating hot water temperature, the port 16 of the cut-back valve 16
a, 16c are in communication, port 16b is closed, and switching valve 1
Ports 1.7b and 17c of 7 are connected, baud) 1
7a is occluded. In this way, the high temperature engine cooling water passes through the engine cooling water heat retention tank 5, the pipe heating passage 4, and returns to the cooling water storage section in the engine, forming a series connection circuit. Heating continues, and high-temperature cooling water is stored in the engine cooling water heat retention tank 5.

Furthermore, a third embodiment of the present invention will be described. FIG. 3 shows a third embodiment of the present invention, and in the same figure, a pipe 20a1 is connected to a cooling water storage section in an engine 3, an engine cooling water insulation tank 5, a pipe 20b1, a passageway 4 for heating the riser, and a pipe 20c. A serial water flow circuit is formed that returns to the cooling water storage section in the engine 3 through the water bonno in the engine 3 when the engine 3 is started. The hot water in the engine cooling water heat retention tank 5 is fully pumped to the live heating water passage 4f.
: The water then flows into the cooling water storage section in Ennon 3.

In this way, the live section 2a is heated, and
Since hot water also flows into the engine block, the engine block temperature rises and warm-up is promoted.

In addition, in each of the above-mentioned embodiments, the following changes can be made to each part.

(1) The live portion may be provided with heat transfer fins or have an uneven surface in order to increase the contact area with the fuel and promote vaporization.

(2) The switching valve may be driven by an electromagnetic type or a vacuum type.

(3) The switching valve may be a water temperature sensing valve that opens and closes by detecting the set temperature of the cooling water.

(4) The fuel supply device is not limited to a carburetor, but may be a fuel injection nozzle.

(5) The signal for switching the water supply circuit may be provided by a timer using a temperature detector.

(6) The riser heating passageway 4 may be configured to flow around the intake pipe together with the riser portion and heat the entire intake pipe.

Since the above is 9, the present invention stores all the heat of high-temperature engine cooling water in the engine cooling water heat retention tank, and allows the water to flow through the live heating passage of the intake pipe at the time of cold start.
Even when the engine coolant temperature does not rise sufficiently, the entire rib section can be heated immediately, which promotes the vaporization of the fuel that drips into the live section in liquid form without being sufficiently vaporized, making the engine breathable. This enables smooth warm-up without causing misfires, etc., and when engine warm-up is completed, the high-temperature cooling water in the engine passes through the riser heating passageway and the engine cooling water heat retention tank. In addition to continuously heating the live parts, vaporization of the fuel is promoted even after warm-up is completed, completely preventing suffocation during acceleration, and in preparation for the next start, the engine cooling water is kept in the insulating tank. It can constantly supply and store high-temperature hot water.

Furthermore, since the water pump is operated electrically or the like before cold starting to completely heat the rib portion, the startability, especially during cold starting, is improved.

′! ! In addition, the power consumption is extremely low compared to conventional electric heating, and the negative energy consumption can be greatly reduced.

It has many excellent effects as a fuel vaporization accelerator for engines.

[Brief explanation of drawings]

Fig. 1 is a system configuration diagram of the first embodiment of the present invention, Fig. 2 is a system configuration diagram of the second embodiment of the above, and Fig. 3 is a system configuration diagram of the second embodiment of the same.
FIG. 1 is a system configuration diagram of an embodiment. DESCRIPTION OF SYMBOLS 1... Carburetor, 2... Intake pipe, 2a... Live part, 3... Engine, 4... Live heating water passage, 5
・°・Engine cooling water heat retention tank, 6a to 61.19a
~19g, 20a~20c...Piping, 7, 8, 9゜1
6.17...Switching valve, 10.18...Water pump, 11...Heat water temperature detector, 12...Engine cooling water temperature detector, 13...Control unit. Figure 2

Claims (1)

[Claims] 1. A live heating passageway is formed in the intake pipe that connects the carburetor and the engine, and is connected to both the cooling water storage section in the engine and the engine cooling water heat retention tank, respectively. Ennon's fuel vaporization accelerator. 2. A first water passage circuit that connects the live heating passageway and the engine cooling water heat retention tank, and a cooling water storage section in the engine that connects the live heating passageway and the engine cooling water insulation tank all in parallel. A second water passage circuit is provided, and these first water passage circuits are provided with a second water passage circuit. The fuel vaporization accelerator for an engine according to claim 1, which is switchable to either one of the second water flow circuits. 3. A first water passage circuit that connects the live heating water passageway and the engine coolant heat retention tank, and connects the cooling water storage section in the engine, the engine coolant heat retention tank, and the live heating water flow passageway in series. A second water passage circuit is provided, and the first water passage circuit is connected to the first water passage circuit. The fuel vaporization accelerator for an engine according to claim 1, which is switchable to either one of the second water flow circuits. 4. Detect the engine cooling water temperature and the Ennon cooling water temperature insulating tank water temperature...J, No. 1. The fuel vaporization promoting device for an engine according to claim 2 or 3, wherein switching control is performed to either one of the second water passages.