AU2006201759A1 - Starting Apparatus for Liquified Petroleum Gas Injection Vehicle and Method for Controlling the Same - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name of Applicant: Actual Inventor: Address for Service: Invention Title: Hyundai Motor Company Deok Ryol Kim HODGKINSON McINNES PAPPAS Patent Trade Mark Attorneys Levels 3, 20 Alfred Street MILSONS POINT NSW 2061 "Starting Apparatus for Liquified Petroleum Gas Injection Vehicle and Method for Controlling the Same" Details of Basic Application: Korea Patent Application No. 10-2005-0080931 Filed 31 August 2005 The following statement is a full description of this invention, including the best method of performing it known to us: P20495AU00 STARTING APPARATUS FOR LIQUIFIED PETROLEUM GAS INJECTION VEHICLE AND METHOD FOR CONTROLLING THE SAME CROSS-REFERENCE TO RELATED APPLICATION This application claims priority to and the benefit of Korean Patent Application No. 10-2005-0080931 filed in the Korean Intellectual Property Office on August 31, 2005, the entire content of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a vehicle applying a liquefied petroleum gas injection (LPI) system.

More particularly, the present invention relates to a starting apparatus for an LPI vehicle, and a method controlling the same, where a starter motor operates under a condition that fuel pressurized to an injector is kept in a liquid state and in a case that contact points of an ignition switch and a starter switch, which are separated, are determined as being in engine start-on request positions for starting an engine.

Description of the Related Art Generally, a liquefied petroleum gas injection (LPI) system applied to a LPG vehicle includes a fuel pump mounted to a tank.

In addition, the LPI system means a liquefied petroleum gas multi point injection (LPG MPI) system pressurizing fuel by a fuel pump and injecting the fuel to each cylinder through an injector in a state that the fuel is kept in a liquid state.

An engine control means mounted to the vehicle including the LPI system turns on a starting lamp and then detects a fuel pressure pressurized to the injector for enhancing startability in a case that an ignition-on selection IG1 of an ignition switch is detected.

And then, the engine control means determines if the fuel pressurized to the injector is kept in a liquid state on the basis of a predetermined saturated vapor pressure diagram.

And then, if the fuel is kept in the liquid state, the engine control means turns off the starting lamp.

And then, if a driver locates an ignition switch contact point to a start-on contact point, the engine start-on can be realized.

However, a case where the driver ignores the indication of the starting lamp and locates the ignition switch contact point to the start-on contact point occurs often before the starting lamp is turned off.

In this case, because the state is where a normal pressurization in the injector is not realized, the fuel in the liquid state is not created, problems occur that engine startability is deteriorated and discontent of the driver occurs.

In addition, because operating time of a starter motor is elongated by delaying an engine starting, problems occur that the starter motor is broken and a battery is broken by which unnecessary power is wasted.

In a serious case, a problem occurs that the engine cannot start.

In addition, a problem occurs that exhaust emission is deteriorated because of successive attempts to start the engine in a state where a thin mixture ratio of the fuel is kept.

The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a starting apparatus for an LPI vehicle, and a method controlling the same, having advantages of a starter motor operating in a condition that fuel pressurized to an injector is kept in a liquid state and in a case that contact points of an ignition switch and a starter switch, which are separated, are determined as being in engine start-on request positions for starting an engine.

An exemplary embodiment of the present invention provides a starting apparatus for a liquefied petroleum gas injection vehicle containing: a battery; a starter motor; an ignition switch defining contact points ACC, IG2, and IG1 selected by an ignition key for supplying electric power to respective elements mounted to the vehicle; a starter switch mounted in a predetermined position of the vehicle separately from the ignition switch and outputting an engine starting-on request signal; an electronic control unit (ECU) determining whether a fuel is in a liquid state, controlling a starter motor operation in a condition that the fuel is kept in a liquid state, and detecting a temperature and a pressure of the fuel pressurized to the injector in a case that signals from the ignition switch and the starter switch are start-on requests; and a relay driving the starter motor in response to a control from the ECU. The ECU controls the injector when the starter motor is controlled such that a non-synchronizing fuel injection can be realized in the engine, and controls an igniting apparatus operation to generate a spark discharge in a spark plug. The ECU stops a starter motor in a case where an engine speed is more than a starting rotation speed in a state where the ECU controls engine start-on. One side of an inner coil of the relay is connected to the ECU, one side of an inner switch of the relay is connected to a starter coil of the starter motor, and inner contact points are switched by a control signal applied from the ECU to operate the starter motor.

A method for controlling an LPI vehicle includes determining if signals from an ignition switch and a starter switch are start-on requests in an engine-off state, determining if fuel is in a liquid state by detecting a temperature and a pressure of the fuel pressurized to an injector in a case that the signals are the start-on requests, trying start-on by controlling an injector, an igniting apparatus, and a starter motor in a case where the fuel pressurized to the injector is in a liquid state, and stopping the starter motor in a case that an engine speed is more than a starting rotation speed in response to trying start-on of the engine.

The starter motor is operated only in the case that signals from the ignition switch and the starter switch are simultaneously determined as engine start-on requests. The determination of whether the fuel pressurized to the injector is in the liquid state is realized on the basis of a predetermined saturated vapor pressure diagram by modeling of LPG characteristics.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a starting apparatus of an LPI vehicle according to an exemplary embodiment of the present invention.

FIG. 2 is a flowchart showing a starting control operation in an LPI vehicle according to an exemplary embodiment of the present invention.

<Description of Reference Numerals Indicating Primary Elements in the Drawings> ignition switch 20: battery starter motor 40: starter switch ECU 60: relay DETAILED DESCRIPTION OF THE EMBODIMENT An exemplary embodiment of the present invention will hereinafter be described in detail with reference to the accompanying drawings.

A starting apparatus for a liquefied petroleum gas injection (LPI) vehicle according to an exemplary embodiment of the present invention includes an ignition switch 10, a battery 20, a starter motor 30, a starter switch 40, an electronic control unit (ECU) 50, and a relay The ignition switch 10 defines contact points ACC, IG2, and IG1 selected by an ignition key for supplying electric power to respective elements mounted to the vehicle.

The battery 20 supplies the electric power to the selected elements in response to the contact points ACC, IG2, and IG1 in an engine-off state.

In addition, the battery 20 supplies the electric power to the starter motor when the engine starts and is charged by an alternator (not shown) which generates voltage.

The starter motor 30 operates in a case where a start-on control of the engine is realized such that the engine starts by operating a flywheel.

The starter switch 40 is mounted in a predetermined position of the vehicle separately from the ignition switch 10 and outputs an engine start-on request signal by selection of the contact point by a driver.

If the contact point of the ignition switch 10 is located in the contact point IG1, the power is supplied to all of the elements in the vehicle.

The ECU 50 detects a temperature and a pressure of the fuel pressurized to the injector (not shown) in a case where the ECU 50 detects that the ignition switch 10 is located to the contact point IG1 and that a signal requesting the engine start-on is output from the starter switch And then, the ECU 50 determines if the fuel pressurized to the injector is in the liquid state, which is determined on the basis of a predetermined saturated vapor pressure diagram by modeling of LPG characteristics.

In addition, the ECU 50 turns on the contact point of the relay 60 to operate the starter motor 30 in a case where the ECU 50 determines that the fuel is kept in the liquid state.

In addition, the ECU 50 controls the injector when the starter motor 30 is controlled such that a non-synchronizing fuel injection can be realized in the engine.

In addition, the ECU 50 controls an igniting apparatus operation to generate a spark discharge in a spark plug.

In addition, as described above, the ECU 50 detects an engine speed in a state of controlling the engine start-on and if the engine speed is more than a predetermined rotation speed, the ECU 50 determines that the engine is in the start-on state and stops the starter motor One side of an inner coil of the relay 60 is connected to the ECU 50 and one side of an inner switch of the relay 60 is connected to a starter coil of the starter motor In addition, inner contact points of the relay 60 are switched by a control signal applied from the ECU 50 to operate the starter motor An exemplary embodiment of the present invention of an operation to operate a starting control including the operation as described above will hereinafter be described in detail with reference to FIG 2.

The ECU 50 determines if the ignition switch 10 is located to the contact point IG1 by the ignition key in a state where the engine stops, at the step $101.

At the step S101, if the ignition switch 10 is located to the contact point IG1, the ECU 50 then determines if a signal from the starter switch 40 is detected as an engine start-on request, at the step S102.

At the step S102, if the signal from the starter switch 40 is the engine start-on request, the ECU 50 then detects a temperature and a pressure of the fuel pressurized to the injector, at the step S103.

And then, the ECU 50 determines if the fuel pressurized to the injector is in the liquid state on the basis of a predetermined saturated vapor pressure diagram by modeling of LPG characteristics, at the step 5104.

At the step 5104, if the fuel is not kept in the liquid state, the ECU returns to the step S103.

In addition, if the fuel is kept in the liquid state, the ECU 50 operates the starter motor 30 by applying a control signal to the relay 60 and by switching on the inner contact point, at the step S105.

Simultaneously, the ECU 50 controls an injector operation such that a non-synchronizing injection is realized and controls an igniting apparatus operation to generate a spark discharge such that the engine starts, at the step S106.

As described above, if the engine is controlled to start, the ECU detects the engine speed.

And then, the ECU 50 determines if a rotation speed of the engine is more than a predetermined rotation speed, if the rotation speed of the engine is detected as a starting rotation speed, at the step S107.

And then, the ECU 50 continues to control the engine start-on by returning to the step S105 if the rotation speed of the engine is less than the starting rotation speed.

In addition, the ECU 50 turns off the inner contact point of the relay such that the operation of the motor 30 stops at the step S108 if the rotation speed of the engine is the starting rotation speed, and keeps a normal engine start at the step S109.

As described above, according to an exemplary embodiment of the present invention, the ignition switch and the starter switch are mounted independently.

In addition, in a case that the two switch signals are determined as engine start-on requests and the fuel pressurized to the injector is kept in the liquid state, the engine starts.

Therefore, according to the exemplary embodiment of the present invention, engine startability and durability are enhanced because unnecessary operation of the starter motor is prevented.

In addition, power consumption of a battery is minimized and exhaust stability is realized because stable startability is realized.

While this invention has been described in connection with what is presently considered to be a practical exemplary embodiment, it is to be understood that the invention is not limited to the disclosed embodiment, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

The term "comprising" (and its grammatical variations) as used herein is used in the inclusive sense of "having" or "including" and not in the exclusive sense of "consisting only of'.

Claims (9)

1. A starting apparatus for a liquefied petroleum gas injection vehicle containing a battery and a starter motor, the starting apparatus comprising: an ignition switch defining contact points ACC, IG2, and IG1 selected by an ignition key for supplying electric power to respective elements mounted to the vehicle; a starter switch mounted in a predetermined position of the vehicle separately from the ignition switch and outputting an engine start-on request signal; an electronic control unit (ECU) determining whether a fuel is in a liquid state, controlling a starter motor operation in a condition that the fuel is kept in a liquid state, and detecting a temperature and a pressure of the fuel pressurized to the injector in a case where signals from the ignition switch and the starter switch are start-on requests; and a relay driving the starter motor in response to a control signal from the ECU.

2. The apparatus of claim 1, wherein the ECU controls the injector when the starter motor is controlled such that a non-synchronizing fuel injection can be realized in the engine, and controls an igniting apparatus operation to generate a spark discharge in a spark plug.

3. The apparatus of claim 1, wherein the ECU stops a starter motor in a case that an engine speed is more than a starting rotation speed in a state where the ECU controls engine start-on.

4. The apparatus of claim 1, wherein one side of an inner coil of the relay is connected to the ECU, one side of an inner switch of the relay is connected to a starter coil of the starter motor, and inner contact points are switched by a control signal applied from the ECU to operate the starter motor.

A method for controlling an LPI vehicle comprising: determining if signals from an ignition switch and a starter switch are start-on requests in an engine-off state; determining if fuel is in a liquid state by detecting a temperature and a pressure of the fuel pressurized to an injector in a case where the signals are the start-on requests; trying start-on by controlling an injector, an igniting apparatus, and a starter motor in a case that the fuel pressurized to the injector is in a liquid state; and stopping the starter motor in a case that an engine speed is more than a starting rotation speed in response to trying start-on of the engine.

6. The method of claim wherein the starter motor is operated only in a case that signals from the ignition switch and the starter switch are simultaneously determined as engine start-on requests.

7. The method of claim 6, wherein the determination of whether the fuel pressurized to the injector is in the liquid state is realized on the basis of a predetermined saturated vapor pressure diagram by modeling of LPG characteristics.

8. A starting apparatus for a liquefied petroleum gas injection vehicle as substantially hereinbefore described and with reference to the accompanying Figures.

9. A method for controlling a liquefied petroleum gas injection vehicle as substantially hereinbefore described and with reference to the accompanying Figures. Dated this 27 th day of April 2006. Hvundai Motor Company By: HODGKINSON MclNNES PAPPAS Patent Attorneys for the Applicant