KR20080111958A - Method for changing fuel of bi fuel car - Google Patents

Abstract

A method for changing fuel of bi-fuel car is provided to reduce fuel consumption due to unnecessary fuel conversion, and improve riding comfort deteriorated due to frequent conversion of fuel used. A method for changing fuel of bi-fuel car comprises a step of executing diagnosis with respect to the diagnosis items predetermined in ON state; and a step of converting fuel used according to diagnosis result of the set diagnosis item predetermined by a manufacturer.

Description

METHOD FOR CHANGING FUEL OF BI FUEL CAR}

1 is a schematic view showing the configuration of a bi-fuel vehicle according to the present invention.

2 is a flowchart illustrating a fuel conversion process according to the present invention.

<Explanation of symbols for the main parts of the drawings>

1: fuel tank 3: engine

30: pressure regulator 40: fuel distributor

50: gas injector 60: interface box

70: gasoline engine control unit

The present invention relates to a fuel switching method of a bifuel vehicle, and more particularly, by a manufacturer among a predetermined diagnostic item of an internal combustion engine for converting fuel used in a bifuel vehicle that can use a gasoline fuel and a gas fuel. The present invention relates to a method for switching fuel used according to a diagnosis result of a diagnosis item.

In general, automobiles use engines using gasoline fuel or gaseous fuel. Recently, gasoline and gas are used in combination to complement the advantages and disadvantages of mutual fuel. At this time, the gas fuel is either compressed natural gas (CNG) or liquid petroleum gas (LPG: liquid platinum gas).

Such a bi-fuel vehicle receives a gasoline injection signal supplied from a gasoline engine control unit to generate a gas injection signal at an interface box, and is configured to supply fuel (LPG or CNG) in the fuel tank to the gas injector according to the gas injection signal. do.

In a bi-fuel vehicle that can use such gasoline and CNENG fuel, since only one fuel is repeatedly used, especially when the gas fuel is CNENG, there is no lubrication effect compared to gasoline fuel, and thus an internal combustion engine for gas fuel Wear occurs and the fuel used is switched to prevent wear of these gaseous fuels.

At this time, the diagnostic item of the internal combustion engine of the gasoline fuel and the diagnostic item of the internal combustion engine of the gaseous fuel are stored in advance in the gasoline engine control unit, and the use fuel is switched according to the diagnostic result of the diagnostic item of the corresponding fuel.

However, since the used fuel switching is performed even when an error occurs in one of the diagnostic items of the fuel internal combustion engine which occurs in a small or temporary manner, the riding comfort is decreased and the engine starting is often turned off.

The present invention has been made to solve such a problem, and the purpose of the present invention is to use fuel by switching the fuel used according to the diagnostic result of the diagnostic item selected by the manufacturer among the diagnostic items of a predetermined internal combustion engine for fuel conversion. Diagnostics of the internal combustion engine of the corresponding fuel for conversion can be set by the manufacturer to reduce fuel consumption due to unnecessary fuel conversion, and fuel conversion method of a bifuel vehicle that can improve ride comfort deteriorated by frequent use of fuel conversion. It is intended to provide.

Fuel conversion method of a bi-fuel vehicle according to an aspect of the present invention for achieving the above object,

In the fuel switching method of a bi-fuel vehicle for driving the engine by providing gasoline fuel and gaseous fuel to each injector using a gasoline engine control unit and an interface box,

a) executing a diagnosis on a predetermined diagnosis item of the internal combustion engine while the ignition key is on; And

b) switching the fuel used according to the diagnosis result of the diagnosis item preset by the manufacturer among the items;

Here, when the corresponding fuel is a gas fuel, predetermined diagnostic items include error emergency stop, error gasoline injection path data, error gas injection line error data, error gas injection path, Error gas system related to gas, error auxiliary devices error data, gas tank almost empty, fuel ready to operate data OK ready to operate, and limit complete data OK with restrictions),

When the corresponding fuel is gasoline fuel, a predetermined diagnosis item may include emergency emergency stop data, error gasoline injection path error data, error gas injection path error data, and gas. Related electronic device error data (error gas system), error auxiliary devices (error auxiliary devices), gas tank almost empty, fuel ready to operate (OK ready to operate), and OK with restrictions (OK with restrictions) It is characterized by that).

According to the present invention, by switching the fuel used according to the diagnosis result of the diagnostic item selected by the manufacturer among the diagnostic items of the internal combustion engine predetermined for the fuel conversion, the diagnostic item of the internal combustion engine of the fuel for use fuel conversion is provided to the producer. It is possible to reduce the fuel consumption due to unnecessary fuel change by setting, and to improve the ride comfort that is reduced due to frequent use of fuel changeover.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the exemplary embodiment of the present invention, a bifuel vehicle using both CNG and gasoline fuel, which are compressed natural gas fuels, will be described as an example.

1 is a view showing the configuration of a bi-fuel vehicle that can be used as a CN fuel of the gasoline and gas fuel of the present invention, Figure 2 is a fuel conversion process through the gasoline engine control unit 70 shown in FIG. This is a flowchart for explaining in detail.

As shown in FIG. 1, the internal combustion engine for CNG fuel of a bi-fuel vehicle according to the present invention includes a fuel tank 1 for storing CNG (Compressed Natural Gas) fuel under a pressurized state, and a fuel. The CNG fuel stored in the tank 1 flows in, and the pressure regulator 30 reduces and discharges the pressure of the CNG fuel introduced below a predetermined threshold value, and the fuel discharged from the pressure regulator 30 flows in. A fuel distributor 40 which is quantitatively controlled by a plurality of solenoids, for example, 5-10 solenoids, according to the load state of the engine 3, and then supplies each gaseous fuel to the intake manifold of the engine 3, A gas injector (nozzle) 50 for injecting the dispensed fuel of the fuel distributor 40 into the combustion chamber of the engine intake manifold, and the engine speed RPM provided from the gasoline engine control unit 70 through the can communication line. ), Throttle position sensor (TPS), ignition A plurality of fuel distributors 40 based on inter-information, manifold absolute pressure (MAP), coolant temperature, fuel temperature in pressure regulator 30, oxygen signals and pressure signals at at least two locations of fuel distributor 40. And an interface box 60 for driving control of the two solenoids.

In addition, since the internal combustion engine related to gasoline fuel in the bi-fuel vehicle according to the present invention is already known, a detailed description thereof will be omitted.

In addition, the interface box 60 is provided to receive a gasoline injection signal generated in the gasoline engine control unit 70 according to the engine state information through the injection line is converted into a gas injection signal.

At this time, the pressure of the compressed CN fuel in the fuel tank 1 is about 200 to 250 bar, and the pressure is reduced by the pressure regulator 30 below a predetermined threshold value (about 2 to 10 bar), so that it is supplied to the engine. The injection pressure of the CNG fuel is approximately 2-10 bar.

In addition, the gasoline engine control unit 70 is provided to switch the fuel used when a failure occurs in the diagnostic item selected by the manufacturer among the diagnostic items of the internal combustion engine of the fuel.

The fuel conversion process of the bifuel vehicle through the gasoline engine control unit 70 will be described in more detail with reference to FIG. 2.

First, a process of converting the fuel used in the gasoline engine control unit 70 from gasoline fuel to gaseous fuel will be described.

That is, in the gasoline engine control unit 70, one or more diagnostic items among predetermined diagnostic items of the internal combustion engine are set and stored in advance by the manufacturer in order to switch the fuel used. The diagnostic items may be related to emergency emergency stop data, gasoline injection path error data, error gas injection line error data, and gas associated with an emergency emergency stop when gasoline fuel is converted into gaseous fuel. Electronic device error data (error gas system), error auxiliary devices (error auxiliary devices), gas tank almost empty, fuel ready data (OK ready to operate), and OK with restrictions to be.

The diagnostic item may include an emergency stop error data, an error gasoline injection path, an error gas injection path error gas, and a gas when the corresponding fuel is gasoline fuel. Electrical equipment error data (error gas system), error auxiliary devices (error auxiliary devices), gas tank almost empty, fuel ready data (OK ready to operate), and limit complete data (OK with restrictions). Thus, the diagnostic item set by the manufacturer is one or more of the plurality of diagnostic items described above. Here, the error auxiliary device includes an CN gas pressure sensor, a CN temperature sensor, a fuel amount sensor, and a pressure sensor of a gas pressure regulating device, wherein the error gas system includes a gas injector 1, 2, 3, 4, 5, 6 cylinders) includes electrical errors on single components.

Subsequently, the gasoline engine control unit 70 is in the ignition key state (101), and determines whether the fuel currently being used is gasoline (103). If the result is the gasoline fuel, the used fuel is converted from gasoline fuel to gaseous fuel. In operation 105, a diagnosis is performed on a plurality of stored diagnostic items.

The gasoline engine control unit 70 receives the diagnostic result of the stored diagnostic item after being set by the manufacturer among the diagnostic results of the plurality of diagnostic items in step 105 (107), and uses the received diagnostic result according to the received diagnostic result. The fuel is converted to gaseous fuel (109).

At this time, the gasoline engine control unit 70 determines a failure when the diagnostic result data of the diagnostic item of the internal combustion engine of gasoline fuel is triggered.

For example, assuming gasoline injection error data and gas tank almost empty are set by the manufacturer as a diagnostic item for fuel conversion, the gasoline engine control unit 70 may If the gasoline injection line is broken through the error gasoline injection path among the diagnostic items of the gasoline fuel internal combustion engine and the fuel amount of the fuel tank is lower than the set value through the gas tank almost empty, the fuel used is gas Switch to fuel.

Subsequently, the gasoline engine control unit 70 determines whether the start-up is turned off (111). If the start-up is turned off, the program is terminated, and if the start-up is not turned off, the flow proceeds to step 103.

Meanwhile, a process of converting gaseous fuel into gasoline fuel through the gasoline engine control unit 70 will be described.

First, in the gasoline fuel control unit 70, among the diagnostic items for the internal combustion engine of gaseous fuel, a diagnostic item for fuel switching is set by the manufacturer and stored in advance.

At this time, the gasoline engine control unit 70 determines that a failure occurs when bit data corresponding to a plurality of diagnostic items of the internal combustion engine is triggered for fuel switching.

The diagnostic items for the internal combustion engine of the gaseous fuel may include emergency emergency stop, error gasoline injection path error data, error gas injection path error data, and electrical equipment related to gas. Error data, error auxiliary devices, gas tank almost empty, fuel ready data, OK ready to operate, and OK with restrictions The fuel used is converted to gasoline fuel according to the diagnostic result of the diagnostic item set by the manufacturer among these diagnostic items.

For example, if a diagnostic item for performing fuel switching is set by the manufacturer for error gas injection path data and gas tank almost empty, the gas injection line error data error gas injection path. ), The fuel used is converted to gasoline fuel when the gas injection line is broken and the fuel amount is below the set value through the gas tank almost empty.

Subsequently, the gasoline engine control unit 70 determines that the fuel currently being used is not gasoline fuel through the step 103, and thus, the gasoline engine control unit 70 determines a gaseous fuel and applies a plurality of predetermined diagnostic items for the conversion from gaseous fuel to gasoline fuel. After performing the diagnosis (205), the process proceeds to step 107 to convert the used fuel from gaseous fuel to gasoline fuel.

As described above, according to the present invention, by switching the fuel used according to the diagnostic result of the diagnostic item selected by the manufacturer among the diagnostic items of the predetermined internal combustion engine for fuel switching, the internal combustion engine of the fuel for use fuel switching By setting the diagnostic items by the manufacturer, it is possible to reduce fuel consumption due to unnecessary fuel conversion, and improve the riding comfort that is reduced due to frequent use of fuel conversion.

As such, those skilled in the art to which the present invention pertains will understand that the present invention may be embodied in other specific forms without changing to the technical spirit or essential features of the present invention. Therefore, the above-described embodiments are to be understood in all respects as illustrative and not restrictive. The scope of the present invention is shown by the following claims rather than the above description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. .

Claims (3)

In the fuel switching method of a bi-fuel vehicle for driving the engine by providing gasoline fuel and gaseous fuel to each injector using a gasoline engine control unit and an interface box, a) executing a diagnosis on a predetermined diagnosis item of the internal combustion engine while the ignition key is on; And b) switching the fuel used according to a diagnosis result of a diagnosis item preset by the manufacturer, among the items. The method of claim 1, wherein the plurality of diagnostic items when the corresponding fuel is gas fuel includes: emergency emergency stop, error gasoline injection path error data, gas injection line error data error gas injection paths, gas-related error gas systems, error auxiliary devices, gas tank almost empty, fuel ready to operate, OK ready to operate, and Fuel conversion method of a bi-fuel vehicle, characterized in that the restriction data (OK with restrictions). The method of claim 1, wherein the plurality of diagnostic items when the corresponding fuel is gasoline fuel includes: emergency emergency stop, error gasoline injection path error data, gas injection line error data ( error gas injection paths, gas related error data system (error gas system), error auxiliary devices (error auxiliary devices), fuel exhaust data (gas tank almost empty), fuel conversion ready data (OK ready to operate), And OK with restrictions.

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