KR20060031116A - Apparatus and method for converting fuel of automobile using both lpg and gasoline - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a fuel switching device and method in a combined gasoline and LPG vehicle, and more particularly, to a gasoline injector and a gasoline injector using CAN communication between a gasoline- And more particularly, to a fuel switching device and method for a vehicle that is controlled by an LPI interface unit. The present invention is based on the finding that in the case of an LPI system having both an LPG and a gasoline engine, in order to switch the fuel currently being driven in accordance with the gasoline and the amount of the LPG fuel supplied from outside and the cooling water temperature, And a gasoline injector for outputting a gasoline injection signal when the injector of the currently operating fuel device is a gas injector of the LPG unit; and a sensor for sensing the gasoline and the amount of the LPG fuel and the coolant temperature And the gasoline is supplied to the interface unit via the can communication.

Vehicle, fuel injection signal, LPI system, ECU

Description

FIELD OF THE INVENTION [0001] The present invention relates to an apparatus and a method for converting an LPG and a gasoline,

FIG. 1 is a block diagram showing a configuration of a fuel switching device of a combined gasoline and LPG vehicle according to an embodiment of the present invention. Referring to FIG.

FIGS. 2A and 2B are graphs showing a gas injection signal and a gasoline injection signal according to an embodiment of the present invention.

3 is a flow chart for explaining the fuel conversion process of the combined gasoline and LPG vehicle according to an embodiment of the present invention.

Description of the Related Art

11: key input unit 13: gasoline fuel device

15: ELPGE FUEL device 17:

19: Gasoline oil type 21:

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an apparatus and a method for converting fuel into an LPG (Liquefied Petroleum Gas) and a gasoline vehicle, and more particularly, A gasoline injector, and a gas injector.

Among the fuels used in automobiles, Li-fueled petroleum gas is used in some passenger cars and vans because it has high octane number and excellent heat resistance and low fuel cost.

When the gasoline is supplied to the engine of the automobile, the gasoline is liquefied. When the gasoline is vaporized, the gasoline is mixed with the air and flammability is set. Therefore, knocking is less likely to occur compared to gasoline and light oil. Vapor- ) Can be prevented, and the application range thereof is gradually increasing as an alternative fuel for gasoline or diesel fuel.

Here, the above-mentioned LPF apparatus feeds the LPF to the injector in a liquid state using a fuel pump, injects the LPF into the cylinder through the injector, and after the air is mixed with the LPF, .

Therefore, the combined vehicle of the LPG and the gasoline is composed of a vaporizer, a mixer and an alpine fuel tank requiring the use of the LPG fuel, a solenoid valve controlling the supply of the LPG fuel, an LPG controlling the solenoid valve, Must be provided.

In the conventional gasoline and LPG vehicles, starting is performed by gasoline fuel, and when a predetermined condition is satisfied after starting the gasoline, for example, when a predetermined time has elapsed after startup and the engine cooling water temperature has become a certain temperature or more And the fuel is automatically switched from gasoline to LPG. The technology of the engine switching device for such an alpine and gasoline combined vehicle is well known in Korean Patent Application No. 1999025086.

The fuel switching device of the conventional gasoline and LPG vehicles is provided with a throttle position sensor, an oxygen sensor, a water temperature sensor and the like as an input to switch the fuel from the outside. And the structure of the relay is very complicated. In addition, LPI (Liquified Petroleum Injection) system, which injects LPG directly to the combustion chamber through an injector through injection control of ISI, eliminates the need for a separate mixer and evaporator and improves fuel efficiency and power performance. There has been a problem in that it is impossible to apply the above-described technology in the case of an LPI system and a gasoline-combined vehicle.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances and an object of the present invention is to provide a gasoline fueling device and a gasoline fueling device in an LPI system and a gasoline- The present invention also provides an apparatus and method for converting fuel in a combined vehicle of an LPG and a gasoline, wherein the performance of the engine can be improved by providing an LPG interface unit capable of controlling the LPG unit.

In order to achieve the above object, according to a first aspect of the present invention, there is provided a fuel switching device for an automotive vehicle,

In both LPI and gasoline vehicles with LPI systems,

In order to switch the fuel currently being driven according to the gasoline and the amount of the LPG fuel supplied and the coolant water supplied from the outside, when the injector of the currently operated fuel system is the gasoline injector of the gasoline fuel system, the first fuel switching mode is executed, And outputs the gasoline injection signal when the currently operating fuel device is a gas injector of the LPF unit,

And gasoline is supplied to the interface unit through a can communication to a signal supplied from a sensor unit for sensing the gasoline, the amount of the LPG fuel, and the coolant temperature.

According to a second aspect of the present invention, there is provided a fuel switching method for a vehicle including both an LPG and a gasoline,

A fuel switching method for an LPG and a gasoline vehicle having an LPG fuel injector for receiving a gasoline and LPG fuel amount and a cooling water ON signal from a gasoline EGR channel via can communication to control a gas injector of the gasoline fueling system and a gas injector of the LPG In this case,

a) driving an engine by injecting an old fuel after startup;

b) checking whether an error has occurred in the injector of the gasoline engine unit according to the signal of the sensor unit supplied from the gasoline iso line, and checking if there is any gasoline fuel if no error occurs;                         

d) outputting a gas injection signal for driving the LP injector by executing a first fuel switching mode when an error occurs in the injector of the gasoline engine device or when there is no gasoline fuel in the step b);

 e) In step b), it is checked whether or not an error has occurred in the LPF when the gasoline fuel is present, and if the error does not occur, it is checked whether the coolant temperature is lower than the reference value and whether or not the LPF is present is checked step; And

f) In the step e), when an error has occurred in the LPF, when the coolant temperature is lower than the reference value, and when there is no LPF, the second fuel switching mode is executed to drive the gasoline injector And a step of outputting a gasoline injection signal.

Preferably, the first fuel switching mode of the method comprises

g-1) counting the number of cylinders when the gasoline injection signal supplied from the interface unit is terminated, and correcting the amount of the LPF according to the LPF compensation value and the LPF compensation value; And

g-2) correcting the gas injection signal according to the corrected amount of the LPF injected after completion of the counting of the cylinder in the step g-1), and outputting the corrected gas injection signal to the LP injector.

Also preferably, the second fuel switching mode of the method comprises

h-1) counting the number of cylinders of the gasoline engine unit when the gas injection signal supplied from the interface unit is terminated, and correcting the gasoline fuel injection amount according to the gasoline fuel pressure compensation value;

and (h-2) correcting the gasoline injection signal according to the calibrated gasoline fuel injection amount after the counting of the cylinder is completed in the step (h-1), and outputting the calibrated gasoline injection signal to the gasoline injector.

According to a preferred embodiment of the present invention, in a combined gasoline and LPG vehicle having an LPI system, in order to switch the fuel currently being driven in accordance with the amount of gasoline fuel, the amount of the LPG fuel and the cooling water temperature supplied from the gasoline- By outputting the fuel injection signal to the injector of the fuel apparatus to be switched from the interface unit, the fuel switching timing can be precisely matched and the engine performance can be further improved.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, an example of an LPG and LPG vehicle employing the LPI system of the present invention will be described as an example.

FIG. 1 is a block diagram showing a configuration of a fuel switching device of a combined gasoline and LPG vehicle according to an embodiment of the present invention. Referring to FIG. FIG. 2 is a graph showing a gasoline injection signal and a gas injection signal output from the interface unit of FIG. 1. FIG.

Referring to FIG. 1, the fuel switching device for a combined gasoline and LPG vehicle according to the present invention includes a key input unit 11 for generating a fuel switching signal in response to a driver's selection, A gasoline fuel device 13 including a gasoline injector for injecting a gasoline injector for injecting an LPG according to an externally supplied LPG injection signal, a shutoff valve, a pump, and a fuel rail assembly, ).

The fuel switching device includes a gasoline eucalyptus 19 for receiving gasoline, an amount of LPG fuel and a cooling water ON signal supplied to the sensor unit 17 and outputting the gasoline and cooling water on signal through can communication, The gasoline injector of the gasoline fuel unit 13 and the gas injector of the LPG unit 15 are connected to the gasoline injector of the gasoline fuel unit 13 in accordance with one of the amount of the LPG fuel and the coolant- And an interface unit 21 for controlling the interface.

The LPI interface unit 21 is connected to the LPG unit 15 and the gasoline fuel unit 13 in accordance with one of the gasoline and the amount of the LPG fuel supplied from the gasoline EGO 19 And the gasoline injection signal to switch the fuel.

That is, when an error occurs in the gasoline fuel unit 13 from the sensor unit 17 or there is no gasoline fuel, the gasoline DC 19 supplies this information to the LPG 21 via the can communication, Upon receiving a signal indicating the occurrence of an error in the fuel device 13 or a signal indicating the absence of gasoline fuel, the above-described LP interface unit 21 outputs the first fuel for switching the gasoline fuel to the LP fuel, Generates a switching signal, and executes the first fuel switching mode in accordance with the first fuel switching signal.

2 (A), the first fuel switching mode is a mode in which the first fuel switching signal is generated at the end point t1 of the gasoline injection signal A output from the LPI interface unit 21 when the first fuel switching signal is generated The number of cylinders is counted, the gas injection quantity is corrected according to the LPF correction value and the LPF correction value, and the gas injection signal for injecting the LPF corrected for the corrected gas injection quantity at the end of the counting of the cylinder is outputted . The ratio of the gas injection time (S1) in which the gas is injected and the gas injection time (S2) in which the next gas is injected is determined according to the correction value of the LPF and the injector flow correction value, and the gas injection signal is generated in accordance with this ratio. And the gas injector of the LP unit 15 is driven in accordance with the generated gas injection signal.

On the other hand, the gasoline DSC 19, which receives a signal indicating the occurrence of an error in the LPG unit 15 from the sensor unit 17, a signal indicating the absence of the LPG fuel, or a signal indicating that the temperature of the cooling water temperature is below the reference value One of these signals is supplied to the LPG 21 via the CAN communication, and the LPG 21, which receives one of the signals supplied from the LPG 13, converts the LPG into gasoline fuel Generates a second fuel switching signal for executing the second fuel switching mode for switching, and executes the second fuel switching mode in accordance with the generated second fuel switching signal.

2B, the second fuel switching mode counts the number of cylinders at the end point t3 of the gas injection signal outputted from the above-described LPI interface unit 21, and corrects the gasoline injection amount And the gasoline injection signal for injecting the gasoline fuel into the corrected gasoline injection amount when the counting of the cylinder is finished. The gasoline injector of the gasoline fuel unit 13 is driven in accordance with the gasoline injection signal.

The first fuel switching signal and the second fuel switching signal are generated in accordance with a signal supplied from the gasoline diesel oil 19 at the interface unit 21.

On the other hand, when the driver selects the fuel switch key (not shown) of the key input unit 11 to switch the fuel, the LP interface unit 21 checks whether the fuel currently being driven is gasoline, Cut mode, and drives the gas injector in the gasoline fuel cut mode, and outputs the gas injection signal corrected according to the first fuel switching mode when the mode is not the gasoline fuel cut mode. If the current driving fuel is not gasoline, the LP interface unit 21 determines whether the mode is the LP mode or the LP mode, drives the gasoline injector when the mode is the LP mode, And outputs the corrected gasoline injection signal in accordance with the switching mode.

3 is a flow chart for explaining the fuel conversion process of the combined gasoline and LPG vehicle according to an embodiment of the present invention. The fuel conversion process of the LPG system having the LPI system according to the present invention will be described.

First, the interface unit 21 generates a gasoline or gas injection signal for injecting a predetermined fuel to drive the engine (step 101).

It is checked whether the fuel switching request signal is inputted from the driver during the execution of the step 101. If the fuel switching request signal is received, it is checked whether the fuel currently being driven is gasoline (step 103) It is checked whether the mode is the gasoline fuel cut mode (104), and the gas injector is driven in the gasoline fuel cut mode. If the mode is not the gasoline fuel cut mode, a first fuel switching signal for switching the gasoline fuel to the LPG is generated (step 107), and the first fuel switching mode is executed in accordance with the first fuel switching signal. Through the first fuel switching mode, the LPI interface unit 21 outputs a gas injection signal for driving the gas injector of the LPG unit 15.

Here, the process of executing the first fuel switching mode in the LPI interface unit 21 is as follows.

First, when the first fuel switching signal is generated in step 107, the number of cylinders of the engine is counted at the end point t1 of the gasoline injection signal output from the LP interface unit 21 (step 109) , Corrects the gas injection amount corrected in accordance with the injector flow and the LPF supplied from the LPF 15 at the end point t2 of the gasoline injection signal (step 111), and checks whether the counting of the cylinder is completed (Step 115) After the cylinder counting is completed, a gas injection signal for injecting the LPF by the gas injection amount corrected in Step 111 is outputted (Step 117). In accordance with the gas injection signal generated in step 117, the gas injector of the LPG unit 15 is driven to drive the engine (step 119).

If the current driving fuel is not the gasoline fuel but the LP fuel is in the LP mode (step 120), the gasoline injector is driven in the LP mode.

In the step 120, a second fuel switching signal for converting the LPG into gasoline fuel is generated (step 122), and when the LPG is not in the LPG mode, In accordance with the switching signal, the LPM interface unit 21 executes the second fuel switching mode. In the second fuel switching mode, the LP interface unit 21 outputs a gasoline injection signal for driving the gasoline injector of the gasoline fuel unit 13.

Here, the process of executing the second fuel switching mode in the LPI interface unit 21 is as follows.

When the second fuel switching signal is generated through step 122, the number of cylinders of the gasoline engine is counted at the end point t3 of the gas injection signal output from the LP interface unit 21 (step 123) , The gasoline injection amount is corrected in accordance with the signal supplied from the gasoline fuel device 13 at the end point t4 of the gas injection signal (step 125). Then, it is checked whether or not the counting of the cylinders is completed (step 129), and if it is finished, the gasoline injection signal for injecting gasoline by the amount of gasoline injection corrected by the step 125 is outputted (step 131). The gasoline injector of the gasoline fuel unit 13 is driven according to the gas injection signal generated in the step 117 to drive the engine (step 133).

After the completion of the fuel switching through step 119 or 133, it is checked whether the engine is turned off (step 145). If the engine is not turned off, the process proceeds to step 101.

If the fuel switching request signal is not received in step 103, it is checked whether an error has occurred in the gasoline engine device (step 135). If no error has occurred, it is checked whether the gasoline fuel is equal to or greater than the first reference value Step 137). If an error occurs in the gasoline engine device 13 through the step 135 or 137, or if the gasoline fuel is equal to or lower than the first reference value, the process proceeds to step 109 to change the first fuel switching mode And a gas injection signal for driving the LPF 15 is output.

On the other hand, if it is determined in step 137 that an error has occurred in the LPF when the gasoline fuel is equal to or greater than the first reference value (step 139), it is checked whether the coolant temperature is lower than the second reference value (Step 141). If it is the second reference value or more, it is checked whether the amount of the LPG is equal to or less than the third reference value (Step 143).

If it is determined in step (139) to step (143) that an error has occurred in the LPF, if the cooling water temperature is lower than the second reference value, and if the LPF is equal to or less than the third reference value, The second fuel switching mode is executed.

As described above in detail, in the gasoline and LPG vehicles having the LPI system, the fuel switching system and the method for the gasoline and LPG vehicles according to the present invention can control the amount of gasoline supplied from the gasoline- By controlling the LPG unit and the gasoline fuel unit according to the amount of the LPG fuel and the cooling water temperature, the engine performance can be further improved by accurately matching the LPG injection signal and the gasoline injection signal during the fuel conversion.

It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. .

Claims (9)

In both LPI and gasoline vehicles with LPI systems, In order to switch the fuel currently being driven according to the gasoline and the amount of the LPG fuel supplied and the coolant water supplied from the outside, when the injector of the currently operated fuel system is the gasoline injector of the gasoline fuel system, the first fuel switching mode is executed, And outputs the gasoline injection signal when the injector of the currently operating fuel device is the gas injector of the LPF unit, And the gasoline is supplied to the interface unit through the can communication with a signal supplied from a sensor unit for sensing the gasoline, the amount of the LPG fuel, and the coolant temperature. 2. The apparatus of claim 1, wherein the < RTI ID = 0.0 > When the fuel switching request signal generated by the driver's selection is received, it is checked whether the currently driven fuel device is an LPF mode, and a predetermined gas injection signal is output when the LPF is in the LPF mode And the fuel is supplied to the engine. 2. The apparatus of claim 1, wherein the < RTI ID = 0.0 > When the fuel switching request signal generated by the driver's selection is received, it is checked whether the currently driven fuel device is the LPG fuel cut mode, and if it is the gasoline fuel cut mode, the predetermined gasoline injection signal is outputted And the fuel is supplied to the fuel tank. 2. The method of claim 1, wherein the first fuel switching mode of the < RTI ID = 0.0 > The number of cylinders is counted when the gasoline injection signal is terminated, the amount of the LPF injected is corrected according to the LPF compensation value and the LPF compensation value, and the gas injection And the signal is corrected to supply the gas to the gas injector. A fuel switching method for an LPG and a gasoline vehicle having an LPG fuel injector for receiving a gasoline and LPG fuel amount and a cooling water ON signal from a gasoline EGR channel via can communication to control a gas injector of the gasoline fueling system and a gas injector of the LPG In this case, a) driving an engine by injecting an old fuel after startup; b) checking whether an error has occurred in the injector of the gasoline engine unit according to the signal of the sensor unit supplied from the gasoline iso line, and checking if there is any gasoline fuel if no error occurs; d) outputting a gas injection signal for driving the LP injector by executing a first fuel switching mode when an error occurs in the injector of the gasoline engine device or when there is no gasoline fuel in the step b);  e) In step b), it is checked whether or not an error has occurred in the LPF when the gasoline fuel is present, and if the error does not occur, it is checked whether the coolant temperature is lower than the reference value and whether or not the LPF is present is checked step; And f) In the step e), when an error has occurred in the LPF, when the coolant temperature is lower than the reference value, and when there is no LPF, the second fuel switching mode is executed to drive the gasoline injector And outputting a gasoline injection signal to the fuel injection valve. 6. The method according to claim 5, wherein the first fuel switching mode g-1) counting the number of cylinders when the gasoline injection signal supplied from the interface unit is terminated, and correcting the amount of the LPF according to the LPF compensation value and the LPF compensation value; And g-2) correcting the gas injection signal according to the corrected amount of the LPF injected after the counting of the cylinder is completed in the step g-1), and outputting the gas injection signal to the gas injector Fuel conversion method. 6. The method according to claim 5, wherein the second fuel switching mode h-1) counting the number of cylinders of the gasoline engine unit when the gas injection signal supplied from the interface unit is terminated, and correcting the gasoline fuel injection amount according to the gasoline fuel pressure compensation value; And h-2) correcting the gasoline injection signal according to the corrected gasoline fuel injection amount after the counting of the cylinder is completed in the step h-1), and outputting the corrected gasoline injection signal to the gasoline injector Fuel conversion method. The method according to claim 5, further comprising the steps of: (c-1) checking whether the fuel switching request signal generated by the driver's selection during the execution of step (a) And if the detected fuel type is gasoline, it checks whether the mode is a gasoline fuel cut mode, drives the gas injector, and if it is not the gasoline fuel cut mode, proceeds to step d) to execute the first fuel switching mode A method of converting fuel for both LPG and gasoline. The method of claim 5, further comprising the steps of: (c-2) checking whether the fuel switching request signal generated by the driver's selection during the execution of step (a) is input, If the detected fuel type is an LPG, it is checked whether it is an LPG cut-off mode. If the LPG fuel cut mode is not the LPG cut mode, the gasoline injector is driven. Fuel ratio of the gasoline-fueled mixture.

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