JPS5958133A - Fuel feeding device for engine - Google Patents

Abstract

PURPOSE:To heighten combustibility and to reduce pumping loss in an engine, in which high temperature fuel is supplied to an air-intake system after it is sent to a cooling unit to be separated into quality-improved gas and liquid gasoline, by supplying the high temperature gas to the engine through a bypass passage when engine loads are light. CONSTITUTION:When an engine 1 is operated, mixture fuel transferred from a fuel tank 4 by a pump 12 is preheated in a cooling unit 15 wherein alcohol is transformed into quality-improved gas while gasoline into gaseous gasoline. In normal operation, these two kinds of gaseous fuel are sent via a gaseous fuel passage 14 from a reaction unit 10 to the cooling unit 15 wherein they are separated into quality-improved gas and liquid gasoline. The quality-improved gas is sent to an air-intake passage 2 through a supply passage 17 and a mixer 7 while the liquid gasoline is sent to the air-intake passage 2 through a supply passage 18 and a fuel injection valve 9. On the other hand, when engine loads are light, directional control valves 13 and 16 are switched according to a detector 20 so that the fuel is supplied to the passage 2 through a bypass passage 19 and the mixer 7 without changing its gaseous state. At that time, a control circuit 21 reduces or shuts off the fuel injection from the valve 9. With this contrivance, the combustibility can be improved, drivers are allowed to depress the pedal to a large extent, and the pumping loss can be decreased.

Description

[Detailed description of the invention] The present invention relates to an engine fuel supply system.

In recent years, efforts have been made to put into practical use technology that uses alcohol and gasoline together as engine fuel, but conventionally alcohol and gasoline were stored in separate tanks and the alcohol was reformed using a reformer to produce reformed gas. A system has been proposed in which the fuel and gasoline are supplied to one intake system of the engine through separate routes. However, such a system requires two fuel tanks, one for alcohol and one for gasoline, and when mixed fuel of alcohol and gasoline becomes commercially available, the proposed method cannot be adopted as is. .

Therefore, the present invention provides a reactor that converts the mixed fuel into alcohol reformed gas and gaseous gasoline, and cools the gasified mixed fuel with a cooler to separate it into reformed gas and liquid gasoline. One of the objects of this invention is to solve the above-mentioned problems by supplying each of them to the intake system of the engine.

By the way, when the engine is operated under a light load, the engine temperature or the exhaust gas temperature tends to be low. For example, to solve the problem of temperature drop,
Gu! As described in Publication No. 2, in a methanol reforming gas engine, the light load operation of the engine is detected to increase the reforming hot water temperature when reforming methanol, thereby improving the reforming efficiency. I have a suggestion.

However, in the proposal mentioned in Section 2, after reforming, the reformed gas is cooled by a gas cooler (cooler), so the cooled reformed gas is supplied into the intake air, and as a result, light load There is a drawback that the pumping loss is large (this is a disadvantage).It is also possible to reheat the reformed gas and liquid kalin that have been cooled and separated.

A separate heating hand is required, and the device is complicated (some problems may occur).

In view of the above, the present invention provides an engine in which high-temperature fuel gasified in a reactor is sent to a cooler, separated into reformed gas and liquid gasoline, and then supplied to the intake system. A bypass passage is provided to supply fuel to the intake system, and when the engine is under light load, high-temperature fuel can be supplied to the engine through the bypass passage, improving combustibility and reducing pumping loss. The present invention provides a fuel supply system for an engine.

EMBODIMENT OF THE INVENTION Hereinafter, the structure of this invention is demonstrated based on Example I detailed drawing.

1 is an engine, 2 is an intake passage of the engine 1, 6 is an exhaust passage of the engine 1, and 4 is a u/S PI tank that stores mixed fuel t1 of alcohol and gasoline.

The intake passage 6 includes an air cleaner 5, an air flow meter 6, a mixer 7,
A throttle valve 8 and a fuel injection valve 9 are arranged in this order. The mixer 7 generates a 1v6 warm combustion t1 of the reformed gas to be described later or a scum-like mixture of the reformed gas and gaseous kanrin.
is introduced into the intake passage 2 and mixed with intake air.

On the other hand, the fuel injection valve 9 injects liquid gasoline into the intake passage 2.

In the exhaust passage 6, the alcohol in the mixed fuel 1 is reformed into a reformed gas consisting of hydrogen and carbon monoxide, and
A reactor 10 is provided for converting gasoline in a mixed fuel into a gaseous state. A fuel passage filled with a reforming catalyst is disposed inside the reactor 10, and an inlet of the fuel passage is connected to the fuel tank 4 via a liquid fuel passage 11, so that the mixed fuel flows into the fuel tank 4. It is sent by a pump 12 from In this reactor 1o, exhaust gas from the engine 1 is supplied to the outer periphery of the fuel passage, and the heat of the exhaust gas is used to promote the activity of the reforming catalyst. Pt is used as a reforming catalyst.

Precious metals such as Pd, Rh, Ru, Ir, Os, etc. or Ni.

Any seven base metals such as Co, Fe, Cr, Zn, etc. or a combination thereof are used.

On the other hand, the fuel passage outlet of the first reactor 10 is a three-sided first I,
It is connected to a cooler 15 via a gaseous fuel j1η path 14 with an IJ switching valve 16 interposed therebetween, and the high temperature fuel gasified by the first reactor 10 is guided to the cooler 15. The liquid fuel passage 11 passes through the interior thereof, and heat exchange is performed between the low temperature mixed fuel flowing through the liquid fuel passage 11 and the gaseous high temperature fuel sent from the reactor 10. , which heats the mixed fuel and cools the gaseous high-temperature fuel to separate it into reformed gas and liquid gasoline.

One end of a gas supply passage 17 with a three-way type first switching valve 16 interposed is connected to the earthen wall of the cooler 15, and the other end of the gas supply passage 17 is connected to the mixer 7 of the intake passage 2. has been done. Further, one end of a gasoline supply passage 18 is connected to the bottom wall of the cooler 15, and the other end of the gasoline supply passage 18 is connected to the fuel injection valve 9.

Therefore, the gaseous fuel JtDf through which the high-temperature fuel flows
l';'? The first switching valve 16 provided at 14 and the second switching valve 16 provided at gas supply oil iI'; 417 are connected by bypass juG 19 + iron 1y. That is, the bypass passage 19 branches from the gaseous fuel passage 14 and bypasses the cooler 15 to supply gas oil 1+! It joins i/+17. A detector 20 is connected to both the switching valves 13 and 16 to detect whether the engine is running in the light mode mode.

The 19th switching valve 16 is set to communicate and close the reactor 10 and the cooler 15 except when the engine 1 is under light load, that is, during normal operation. According to the output from the reactor 20, the communication is cut off and the communication is switched between the reactor 10 and the bypass passage 19. On the other hand, the second switching valve 16 is switched between the cooler 15 and the mixer 7 during normal operation. During light load operation, the output from the light load detection Z420 cuts off the communication and switches the bypass passage 19 and mixer 7 to communicate with each other.

Further, the light load detector 20 is connected to the control circuit 21 together with the air flow meter 6, and the control circuit 1+'421 is connected to the fuel t1 injection valve 9, so that the fuel 1 injection valve 9 is activated during light load operation. The amount of gasoline injected is reduced by 11N or the injection is stopped.

The angle load detector 20 is configured to detect light load operation of the engine 1 from the intake pipe negative pressure or the opening degree of the throttle valve 8.

Next, to explain the operation of the second embodiment, when the engine 1 is operated, the mixed fuel 1 is pumped from the fuel P1 tank 4 to the reactor 10 by the action of the pump 12. At this time, this mixed fuel is preheated by if ~ father exchange in the cooler 15.Since the reactor 10 is maintained at a temperature of j16 by the υ1 gas, the alcohol in the preheated mixed fuel is reformed. In addition to efficiently reforming the gasoline into a gas, the gaseous high dIa fuel is sent to the cooler 15 through the gaseous fuel passage 14 during normal operation 11.J of the engine 1. The reformed gas is cooled in the cooler 15 and separated into reformed gas and liquid gasoline.The reformed gas stored in the cooler 15 is combined with the intake negative pressure acting on the mixer 7 and the pressure exerted by the pump 12. The liquid gasoline is supplied from the mixer 7 to the intake passage 2 through the gas supply passage 17.Also, liquid gasoline passes through the gasoline supply passage 18 from the fuel injection valve 9 to the intake air 111 detected by the air flow meter 6. 111. (Injected into the fire passage 2.

On the other hand, when the engine 1 is operating at a light load, the light load detector 2
The output from 0 switches the ff4/vJ switching valve 13 and the second switching valve 16, and the high-temperature fuel sent from the reactor 10 passes through the bypass passage 19 in a gas state and is supplied from the mixer 7 to the intake passage 2. control circuit 2
The amount of gasoline injected from the fuel injection valve 9 according to the output from 1? kf or injection is stopped. In this case, since high-temperature fuel is supplied to the engine 1, a decrease in engine Wim ff or exhaust gas d1^ is prevented, and since gasoline is supplied to the engine 1 in a gas state (atomized state), combustion Sexuality improves. The intake air temperature rises due to the supply of hot fuel t1, which lowers the charging efficiency and causes the driver to press the accelerator pedal of the car thicker (as if pressing down on it) to overcome the lack of output. , the opening degree of the throttle valve 8 is wide.

Pumping loss of the engine 1 is reduced.

In the second embodiment, the fuel injection valve 9 was used to supply liquid gasoline to the intake passage 2, but a carburetor may also be used. In this case, the gasoline supply i11 is adjusted by the throttle valve 8.

As described below, according to the present invention, gaseous high temperature fuel can be supplied to the engine through the innox passage during light load operation of the engine, and the
<Since this gasoline is supplied to the engine in the form of a gas, it has the excellent effect of reducing the engine's power consumption and efficiency, as well as reducing pumping losses in the engine. .

[Brief explanation of drawings]

The drawing is an overall configuration diagram of an engine 0 fuel supply system illustrating an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1...Engine, 2...Intake passage, 6.Exhaust passage, 4.Fuel tank, 10.Reactor, 11.Liquid state 1 passage, 16..First switching valve, 14. Gaseous fuel passage, ``15 Cooler, 16... No. !Switching valve,''
17 ・ Gas supply passage, 18 Pf' Norin supply passage, 19 Binogus passage, 20 ... Light load detector

Claims (1)

[Claims] +1+ A reactor that reforms the alcohol in the mixed fuel of gasoline and alcohol and turns the gasoline into a gas, and a reactor that gasifies the 11com temperature fuel in the reactor and guides it to the cooler. A PI passage, a gas supply passage and a gasoline supply passage that respectively supply the reformed gas and liquid gasoline separated by the cooler to the intake system of the engine, and a gas supply passage that branches from the fuel passage and bypasses the cooler to supply gas. A bypass passage that merges with the passage, a light load detector that detects light load operation of the engine, and a switching device that switches the flow direction of the high temperature fuel to the bypass passage side based on the output of the light load detector. Features: Engine fuel supply system.