KR102322743B1 - Fuel injector of Gasoline-LPG bi-fuel engine system - Google Patents

Abstract

In a dual fuel supply system that selectively uses gasoline and liquefied petroleum gas (LPG) as engine fuel, a separate control device is used to control the injection timing and injection amount of gasoline fuel and LPG fuel. It's about the technology that makes it possible.
The fuel injection device of the gasoline-LPG dual fuel supply system according to the present invention includes an engine providing driving power to a gasoline vehicle, a gasoline injector connected to a gasoline supply unit containing gasoline and injecting gasoline into the engine, and an LPG supply unit containing LPG. An LPG injector that is connected to and injects LPG into the engine, a gasoline ECU that outputs fuel supply mode information of a gasoline vehicle and generates and outputs an injection control signal of the gasoline injector, and an LPG injection amount and injection applied from the dual fuel control unit An LPG control unit that generates an injection control signal of an LPG injector based on timing information and outputs it to the LPG injector, a sensor unit comprising at least one sensor that measures the state of the engine, and the gasoline ECU and the gasoline injector , when the fuel supply mode applied from the gasoline ECU is the gasoline mode, a route is set so that signals are transmitted/received between the gasoline ECU and the gasoline injector, and in the case of the LPG mode, a preset dummy signal is applied to the injection control signal applied from the gasoline ECU. In addition to transmitting to the gasoline ECU, it is configured to include a dual fuel control unit that determines the injection amount and injection timing of the LPG injector based on vehicle status information and transmits it to the LPG control unit, and in the LPG mode, the LPG control unit controls the exhaust gas temperature When the temperature exceeds a preset specific temperature, the injection control signal of the LPG injector is changed so that the LPG injection amount is further reduced and transmitted to the LPG injector. By generating a gasoline injection control signal corresponding to and transmitting it to the gasoline injector, it is characterized in that it is configured so that the mixed combustion fuel of gasoline and gas is supplied to the engine.

Description

Fuel injector of Gasoline-LPG bi-fuel engine system

In a dual fuel supply system that selectively uses gasoline and liquefied petroleum gas (LPG) as engine fuel, a separate control device is used to control the injection timing and injection amount of gasoline fuel and LPG fuel. It's about the technology that makes it possible.

Recently, as interest in eco-friendly vehicles is increasing, electric vehicles, hydrogen fueled vehicles, hybrid vehicles, and bi-fuel vehicles are emerging.

In particular, a bi-fuel vehicle, that is, a bi-fuel vehicle, is a method in which two fuels are used together in one vehicle, unlike a hybrid vehicle. For example, when using LPG and gasoline as fuel, the driver can select the fuel and engine according to the driving situation so that gasoline is used as the main fuel for city driving and LPG as the main fuel for high-speed driving.

As described above, the bi-fuel vehicle is a new concept eco-friendly vehicle in which the driver wants to increase fuel efficiency by selecting fuel according to the driving situation.

In general, a fuel used in a bi-fuel vehicle uses both gasoline and gas in order to supplement the mutual advantages and disadvantages of gasoline and gas.

The bi-fuel vehicle is applied with a bi-fuel (BI-FUEL) system for selectively using any one of gas and gasoline, and is generally configured to supplementally supply gas fuel to a gasoline vehicle.

That is, the bi-fuel system generates a gas injection signal corresponding to the gasoline injection signal supplied from the gasoline engine control unit and supplies the gas to the engine by supplying the gas to the gas injector, or the gasoline injection signal supplied from the gasoline engine control unit to the gasoline injector. to supply gasoline to the engine.

However, since the output characteristic of the vehicle is reduced when gas fuel is supplied rather than gasoline, a method for selectively supplying gasoline and gas fuel while maintaining the output characteristic of the vehicle is required.

1. Korea Patent No. 10-1593625 (Title of the invention: engine control device and method for bi-fuel vehicle) 2. Korea Patent No. 10-2073628 (Title of the invention: Gasoline fuel supply control device and method for natural gas and gasoline bi-fuel vehicles)

Accordingly, the present invention relates to a dual fuel supply system that selectively uses gasoline and liquefied petroleum gas (LPG) as engine fuel, using a separate control device to inject gasoline fuel and LPG fuel And it is a technical object to provide a fuel injection device of the gasoline-LPG dual fuel supply system that allows the injection amount to be controlled.

According to one aspect of the present invention for achieving the above object, gasoline-LPG, which is equipped with an aftermarket vehicle LPG supply device in a gasoline vehicle to selectively use LPG and gasoline as fuel for a gasoline engine in a gasoline vehicle In the dual fuel supply system, an engine providing driving force to the gasoline vehicle, a gasoline injector connected to a gasoline supply unit containing gasoline to inject gasoline into the engine, and an LPG supply unit containing LPG to inject LPG into the engine Based on the information on the LPG injection amount and injection timing applied from the gasoline ECU, the dual fuel control unit and the gasoline ECU that generates and outputs the injection control signal of the gasoline injector and outputs the fuel supply mode information of the gasoline vehicle, the injection of the LPG injector An LPG control unit that generates a control signal and outputs it to the LPG injector, a sensor unit including at least one sensor for measuring the state of the engine, and a fuel supply mode that is positioned between the gasoline ECU and the gasoline injector and is applied from the gasoline ECU In the gasoline mode, a route is set so that signals are transmitted and received between the gasoline ECU and the gasoline injector, and in the LPG mode, a preset dummy signal for the injection control signal applied from the gasoline ECU is transmitted to the gasoline ECU, and the vehicle It is configured to include a dual fuel control unit that determines the injection amount and injection timing of the LPG injector based on the status information and transmits it to the LPG control unit, and in the LPG mode, the LPG control unit is configured to control the LPG when the exhaust gas temperature exceeds a preset specific temperature. The injection control signal of the LPG injector is changed so that the injection amount is further reduced and transmitted to the LPG injector, and the LPG reduction information is transmitted to the dual fuel control unit, and the dual fuel control unit generates a gasoline injection control signal corresponding to the LPG reduction information There is provided a fuel injection device of the gasoline-LPG dual fuel supply system, characterized in that by transmitting it to the gasoline injector, the mixed combustion fuel of gasoline and gas is supplied to the engine. .

In addition, the LPG control unit generates an injection control signal of an LPG injector with a reduced LPG injection amount when the exhaust gas temperature exceeds 1100° C., and the reduced LPG injection amount is 20% or less of the LPG injector injection amount received from the dual fuel control unit. There is provided a fuel injection device of a gasoline-LPG dual fuel supply system, characterized in that it is set.

According to the present invention, it is possible to convert a gasoline engine into a gasoline-LPG bi-fuel engine without changing the engine structure of a gasoline vehicle, and, as well as gasoline fuel and LPG selectively supplied using a separate control device regardless of gasoline ECU By being able to control the injection timing and injection amount of fuel, the vehicle can operate more economically while ensuring vehicle output characteristics.

1 is a view showing a schematic configuration of a fuel injection device of a gasoline-LPG dual fuel supply system according to the present invention.
Figure 2 is a block diagram showing the functional separation of the internal configuration of the dual fuel control unit 800 shown in Figure 1;
3 is a block diagram showing the function of the control unit 840 shown in FIG. 2 separated for each fuel supply mode.
Figure 4 is a view for explaining the operation of the fuel injection device of the gasoline-LPG dual fuel supply system shown in Figure 1;

The configuration shown in the embodiments and drawings described in the present invention is only a preferred embodiment of the present invention, and does not express all the technical ideas of the present invention, so the scope of the present invention is the embodiment and drawings described in the text should not be construed as being limited by That is, since the embodiment may have various changes and may have various forms, it should be understood that the scope of the present invention includes equivalents capable of realizing the technical idea. In addition, since the object or effect presented in the present invention does not mean that a specific embodiment should include all of them or only such effects, it should not be understood that the scope of the present invention is limited thereby.

All terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Terms defined in a commonly used dictionary should be interpreted as being consistent with the meaning of the context of the related art, and cannot be interpreted as having an ideal or excessively formal meaning not explicitly defined in the present invention.

First, the present invention is applied to a gasoline-LPG dual fuel supply system in which an aftermarket vehicle LPG supply device is mounted on a gasoline vehicle to selectively use LPG and gasoline as fuel for a gasoline engine in a gasoline vehicle.

1 is a view showing a schematic configuration of a fuel injection device of a gasoline-LPG dual fuel supply system according to the present invention.

1, the fuel injection device of the gasoline-LPG dual fuel supply system according to the present invention is an engine 100, a gasoline supply unit 200, an LPG supply unit 300, a gasoline injector 400, an LPG injector 500 ), a gasoline ECU 600 , an LPG control unit 700 , and a dual fuel control unit 800 .

Here, the engine 100, the gasoline supply unit 200, the gasoline injector 400, and the gasoline ECU 600 are components that are fixedly mounted on the gasoline vehicle, and the LPG supply unit 300, the LPG injector 500, and the LPG control unit 700 and the dual fuel control unit 800 are components of an LPG supply device for a vehicle that is installed for an aftermarket in a gasoline vehicle.

The gasoline ECU 100 performs overall control processing for a gasoline vehicle, and in particular is connected to various in-vehicle devices and sensors to determine the state of the vehicle and controls the operation of the connected devices based on this. .

In particular, in the dual fuel supply system applied to the present invention, the gasoline ECU 600 , which is genuinely mounted on a gasoline vehicle, provides fuel supply-related vehicle state information to the LPG control unit 700 and the dual fuel control unit 800 .

1 , the engine 100 burns fuel supplied from the gasoline supply unit 200 and the LPG supply unit 300 to provide driving force to the vehicle.

At this time, the gasoline supply unit 200 supplies gasoline fuel to the engine 100 through the gasoline injector 400 , and the LPG supply unit 300 supplies LPG fuel to the engine 100 through the LPG injector 500 .

The gasoline supply unit 200 is configured to include a gasoline tank containing gasoline and a gasoline pump for flowing gasoline in the gasoline tank. And, the LPG supply unit 300 is configured to include an LPG tank in which the LPG is accommodated, an LPG solenoid valve, an LPG pressure gauge, a vaporizer, and an LPG filter.

In addition, the gasoline injector 400 is connected to the gasoline supply unit 200 to inject gasoline into the engine 100 , and the LPG injector 500 is connected to the LPG supply unit 300 to inject LPG into the engine 100 . spray it

The gasoline ECU 600 provides a gasoline fuel related signal to be transmitted to the engine 100 to the dual fuel control unit 800 . The gasoline ECU 600 outputs fuel supply mode information of the gasoline vehicle and generates and outputs an injection control signal for injecting gasoline from the gasoline injector 400 . Here, the setting of the fuel supply mode may be arbitrarily set by the driver, or may be automatically set based on the driving state of the driver or the engine state of the vehicle.

The LPG control unit 700 generates an injection control signal for injecting LPG and transmits it to the LPG injector 500 . The LPG injector 500 performs LPG injection processing with the engine 100 according to the LPG injection control signal.

The dual fuel control unit 800 is located between the gasoline ECU 600 and the gasoline injector 400, and based on the fuel supply mode information provided from the gasoline ECU 600, the fuel supply operation according to the gasoline mode and the LPG mode. carry out

That is, the dual fuel control unit 800 sets a path so that signals are transmitted and received between the gasoline ECU 600 and the gasoline injector 400 in the gasoline mode, and in the case of the LPG mode, the injection control applied from the R gasoline ECU 600 In addition to transmitting a preset dummy signal for the signal to the gasoline ECU 600, the injection amount and injection timing of the gasoline injector 400 are determined based on vehicle state information, and a corresponding gasoline injector injection control signal is generated. It is transmitted to the gasoline injector 400 .

At this time, the dual fuel control unit 800 may be configured by coupling the sensor unit 900 including at least one sensor for measuring the state of the engine 100 . The sensor unit 900 is configured to include at least one sensor such as an exhaust temperature sensor and a coolant temperature sensor. In addition, the sensor unit 900 is installed in a cylinder (not shown) to which the gasoline injector 400 and the LPG injector 500 are connected at one end and the engine 100 is connected to the other end, so that the sound is generated by abnormal combustion in the cylinder. It may include a knocking sensor that detects whether a knocking phenomenon occurs.

And, the dual fuel control unit 800 is gasoline according to an optimal injection scenario based on the fuel supply related information provided from the gasoline ECU 100 and the LPG control unit 700 and the sensing information collected through the sensor unit 900 . The gasoline injector 400 is controlled by generating an injection control signal to inject fuel. In particular, the dual fuel control unit 800 generates an injection control signal by adjusting the injection amount or injection timing to maintain the vehicle output characteristics over a certain level.

That is, injection control of the LPG fuel supplied to the engine 100 in the LPG mode is actually performed by the dual fuel control unit 800 .

In addition, the dual fuel control unit 800 transmits the LPG injection section information determined in response to the current vehicle state to the LPG control unit 700, thereby generating an LPG injection control signal based on this in the LPG control unit 700 and the LPG injector (500) can be implemented to provide.

2 is a block diagram showing the functional separation of the internal configuration of the dual fuel control unit 800 shown in FIG.

Referring to FIG. 2 , the dual fuel control unit 800 includes first and second communication units 810 and 820 , a data memory 830 , and a control unit 840 .

The first communication unit 810 transmits and receives gasoline supply related information with the gasoline ECU 600 , and the second communication unit 820 transmits and receives LPG supply related information with the LPG control unit 700 , and a CAN (Controller Area Network) carry out communication

The data memory 830 stores a response signal to the gasoline injection control signal applied from the gasoline ECU 600, that is, a dummy signal, and information for generating an injection control signal in the control unit 840 for each vehicle state. Including, various information for controlling the dual fuel supply system is stored.

In particular, in the data memory 830, a dummy signal, which is a normal response signal generated by the gasoline injector 400 for each different gasoline injection control signal, is stored in a table.

The control unit 840 operates in one of the gasoline mode and the LPG mode based on the mode information provided from the gasoline ECU 600 .

The control unit 840 may be functionally separated into a gasoline mode operation module 841 and an LPG mode operation module 842 as shown in FIG. 3 .

The gasoline mode operation module 841 operates when gasoline mode information is applied from the gasoline ECU 600, and transmits the gasoline injection control signal applied from the gasoline ECU 600 in the gasoline mode to the gasoline injector 500 as it is. In addition, the response signal applied from the gasoline injector 500 is transmitted to the gasoline ECU 600 as it is.

That is, the gasoline mode operation module 841 sets a communication path in a pure state in which the gasoline ECU 600 and the gasoline injector 500 are directly connected, so that the gasoline injector 500 is controlled by the gasoline ECU 600 . make it become

The LPG mode operation module 842 is operated when the LPG mode information is applied from the gasoline ECU 600 and includes a dummy transmission block 842A, a state analysis block 842B, and an LPG injection control block 842C.

The dummy transmission block 842A calls a dummy signal corresponding to the gasoline injector normal response signal stored in the data memory 830 in response to the gasoline injection control signal applied from the gasoline ECU 600 in the LPG mode state, and this dummy signal to the gasoline ECU 600 .

This dummy signal performs a function of allowing the gasoline ECU 600 to recognize that the gasoline injector 400 has operated normally with respect to the gasoline control signal generated for controlling the gasoline injector 400 . That is, even if the injection control signal of the gasoline ECU 600 is not transmitted to the gasoline injector 400 when LPG fuel is supplied, the gasoline ECU 600 performs gasoline injection control in response to the injection control signal generated by the gasoline ECU 600 through the reception of the dummy signal. recognized as being made

The state analysis block 842B checks the rail pressure and intake air pressure of gasoline fuel, as well as engine speed, engine load, coolant temperature, LPG fuel temperature and pressure, and exhaust gas temperature, including fuel supply related to the vehicle. Based on the collected information, the vehicle's fuel supply environment is analyzed.

The LPG injection control block 842C determines the LPG injection amount and injection timing to have optimal efficiency based on the current fuel supply environment state analyzed in the state analysis block 842B, and transmits them to the LPG control unit 700 .

At this time, the LPG injection control block 842C may determine the injection amount and injection time of the LPG based on the gasoline fuel pressure and the intake air pressure. In addition, the LPG injection control block 842C may determine the LPG injection timing based on the discharge amount of hydrocarbons and carbon monoxide.

On the other hand, the LPG control unit 700 generates an LPG injection control signal based on the injection amount and injection time of the LPG received from the LPG injection control block 842C, but checks the exhaust gas temperature to set the exhaust gas temperature to a preset specific temperature. , for example, the LPG injection control signal may be changed so that the LPG injection amount is reduced when it exceeds 1100°C. In this case, the reduced LPG injection amount may be set to 20% or less of the LPG injection amount received from the LPG injection control block 842C.

Then, the LPG control unit 700 transmits the LPG reduction information to the dual fuel control unit 800, and the dual fuel control unit 800 additionally generates a gasoline injection control signal to correspond to the LPG reduction information to the gasoline injector 400. can provide

That is, when the exhaust gas temperature is above a certain level in the LPG mode, the LPG fuel and gasoline fuel are mixed in a predetermined ratio under the control of the dual fuel control unit 800 and supplied to the engine 100 .

Next, the operation of the fuel injection device of the gasoline-LPG dual fuel supply system according to the present invention will be described with reference to FIG. 4 . Hereinafter, the operation of the dual fuel control unit 800 will be described.

Basically, the gasoline ECU 600 transmits a gasoline injection control signal for injecting gasoline fuel to the engine 100 to the gasoline injector 400 . And, in the present invention, the dual fuel control unit 800 is coupled between the gasoline ECU 600 and the gasoline injector 400, and the gasoline injection control signal received from the gasoline ECU 600 is coupled to the gasoline injector 400 according to the operation mode. It is bypassed as it is or converted into a gasoline injection control signal having other injection information and transmitted to the gasoline injector 400 .

First, the dual fuel control unit 800 sets the operation mode based on the fuel supply mode information received from the gasoline ECU 600 (ST100). The dual fuel control unit 800 operates in two modes, a gasoline mode and an LPG mode.

In gasoline mode,

When the gasoline injection control signal is received from the gasoline ECU 600 , the dual fuel control unit 800 transmits it to the gasoline injector 400 as it is, and the response signal received from the gasoline injector 400 is transmitted to the gasoline ECU 600 . A transmission/reception path is set between the gasoline ECU 600 and the gasoline injector 400 (ST200).

That is, in the gasoline mode, the dual fuel control unit 800 connects the gasoline ECU 600 and the gasoline injector 400 to operate in a genuine state for supplying gasoline fuel in a gasoline vehicle.

In LPG mode,

When the gasoline injection control signal is received from the gasoline ECU 600 , the dual fuel control unit 800 calls the dummy signal stored in the data memory 830 in response thereto, and transmits it to the gasoline ECU 600 (ST310).

In addition, the dual fuel control unit 800 analyzes the detection signal applied from the sensor unit 900 and the vehicle fuel supply related information collected from the LPG control unit 700 and the gasoline ECU 600 to analyze the current vehicle state, that is, vehicle fuel. The supply environment is determined (ST320).

Next, the dual fuel control unit 800 determines the preset LPG injection amount and injection timing in response to the vehicle fuel supply environment (ST330). In this case, the dual fuel control unit 800 may primarily determine the LPG injection time for one cycle, and determine the injection amount and the injection timing in response to the LPG injection time for one cycle.

And, the dual fuel control unit 800 transmits the LPG injection amount and injection timing information determined in the ST330 step to the LPG control unit 700, and corresponds to the LPG injection amount and the injection timing determined in the ST330 step through the LPG control unit 700 By generating an LPG injection control signal and transmitting it to the LPG injector 500, the LPG injection process is performed (ST340). Accordingly, gasoline-LPG injection processing that satisfies fuel supply efficiency while maintaining vehicle output characteristics is performed.

At this time, the LPG control unit 800 generates an LPG injection control signal so that the LPG injection amount is reduced when the exhaust gas temperature exceeds 1100° C. and transmits the reduced LPG injection amount information to the dual fuel control unit 800 . Then, the dual fuel control unit 800 generates a gasoline injection control signal corresponding to the LPG reduction information and transmits it to the gasoline injector 400 , so that the LPG fuel and the gasoline fuel are supplied to the engine 100 .

100: engine, 200: gasoline supply,
300: LPG supply unit, 400: gasoline injector,
500: LPG injector, 600: gasoline ECU,
700: LPG control unit, 800: dual fuel control unit,
900: sensor unit.

Claims (2)

In the gasoline-LPG dual fuel supply system, which is equipped with an aftermarket vehicle LPG supply device in a gasoline vehicle to selectively use LPG and gasoline as fuel for a gasoline engine in a gasoline vehicle,
an engine for providing driving power to the gasoline vehicle;
A gasoline injector that is connected to a gasoline supply unit in which gasoline is accommodated and injects gasoline into the engine,
An LPG injector that is connected to the LPG supply unit in which the LPG is accommodated and injects LPG into the engine;
A gasoline ECU for outputting fuel supply mode information of a gasoline vehicle and generating and outputting an injection control signal of the gasoline injector;
An LPG control unit that generates an injection control signal of the LPG injector based on the LPG injection amount and injection timing information applied from the dual fuel control unit and outputs it to the LPG injector;
a sensor unit comprising at least one sensor for measuring the state of the engine; and
Located between the gasoline ECU and the gasoline injector, when the fuel supply mode applied from the gasoline ECU is the gasoline mode, a route is set so that the signal transmission/reception is made between the gasoline ECU and the gasoline injector, and in the case of the LPG mode, it is applied from the gasoline ECU and a dual fuel control unit that transmits a preset dummy signal for the injection control signal to the gasoline ECU, determines the injection amount and injection timing of the LPG injector based on vehicle state information, and transmits it to the LPG control unit,
In the LPG mode, when the exhaust gas temperature exceeds a preset specific temperature, the LPG control unit changes the injection control signal of the LPG injector so that the LPG injection amount is further reduced and transmits it to the LPG injector, and also transmits the LPG reduction information to the dual fuel control unit. and, the dual fuel control unit generates a gasoline injection control signal corresponding to the LPG reduction information and transmits it to the gasoline injector, so that the mixed fuel of gasoline and gas is supplied to the engine. of fuel injectors.
According to claim 1,
The LPG control unit generates an injection control signal of an LPG injector with a reduced LPG injection amount when the exhaust gas temperature exceeds 1100° C., and the reduced LPG injection amount is set to 20% or less of the LPG injector injection amount received from the dual fuel control unit. Gasoline-LPG fuel injection device of the dual fuel supply system, characterized in that.

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