KR20230161336A - Sudden acceleration prevention device and method for preventing sudden acceleration - Google Patents

Abstract

The present invention relates to a sudden start prevention device and a sudden start prevention method.
In the present invention, an accelerator detection sensor that provides an accelerator output value, which is an output value depending on the degree to which the driver steps on the accelerator, an engine rpm value (in the case of an electric vehicle, a motor current value applied to the motor), and an accelerator output value input from the accelerator detection sensor. A control unit that determines sudden acceleration using a control unit that generates a second power cut-off signal and an engine ECU data deletion signal if it is determined to be a sudden start, and blocks the power supplied to the fuel pump according to the second power cut-off signal for a first period of time. A sudden start prevention device is disclosed, which includes a second power switch that supplies the power again after power supply.
According to the sudden start prevention device and sudden start prevention method according to the present invention, it can be implemented with fewer circuit parts and operates independently of the vehicle's internal communication network, making it possible to stably prevent sudden start of the vehicle.

Description

Sudden acceleration prevention device and sudden acceleration prevention method {SUDDEN ACCELERATION PREVENTION DEVICE AND METHOD FOR PREVENTING SUDDEN ACCELERATION}

The present invention relates to a sudden start prevention device and a sudden start prevention method. More specifically, the present invention relates to a sudden start prevention device and a sudden start prevention method. More specifically, it detects the degree to which the driver steps on the accelerator and determines whether sudden start is performed using an accelerator detection sensor that operates independently of the vehicle's internal communication network. This relates to a sudden start prevention device and a sudden start prevention method that determines a sudden start situation without using a sudden start situation and then cuts off the power supplied to the vehicle to reset the vehicle.

Modern automobiles are equipped with integrated electronic systems for convenience and energy saving, and the signal processing methods and amount of major data that must be processed simultaneously are increasing. As all of these data must complement each other, data connectivity becomes important.

Nevertheless, a significant number of sudden acceleration accidents occur in cars equipped with modern intelligent electronic systems, which indicates that there are problems with handling them in a centralized ECU.

Regardless of the situation, if a sudden acceleration occurs, the driver will panic and it will be nearly impossible to deal with the situation. When a sudden acceleration occurs, even if the driver responds calmly, the vehicle is in a state where the driver cannot operate it, so a device to solve this problem is needed.

Korean Patent Publication No. 10-2010-0031327 (published on March 22, 2010)

The present invention emerged in response to the above-mentioned need, and is designed to quickly determine situations in which sudden vehicle acceleration occurs and, when it is determined that sudden acceleration has occurred, to cut off the power supplied to the vehicle - at least to cut off the power supplied to the fuel pump and engine ECU. The purpose is to provide a sudden start prevention device and a sudden start prevention method that stops the vehicle from running and deletes the data that caused the sudden start, thereby quickly returning to normal.

The above object of the present invention is to provide a device for preventing sudden acceleration of a vehicle, which includes a vehicle power unit that supplies power to the vehicle, a plurality of ECUs including an engine ECU connected to the vehicle's internal communication network, a fuel pump, and an OBD terminal that provides vehicle status information. An accelerator detection sensor that provides an accelerator output value, which is an output value depending on the degree to which the driver presses the accelerator, and - the accelerator detection sensor is a detection sensor that is not connected to the vehicle's internal communication network and operates independently of the vehicle's internal communication network. Lim - a control unit that determines whether sudden acceleration is performed using vehicle status information including the accelerator output value and engine rpm value input from the accelerator detection sensor, and generates a second power cut signal and an engine ECU data deletion signal if sudden acceleration is determined; It is installed between the vehicle power supply unit and the fuel pump and includes a second power switch that cuts off power supplied to the fuel pump according to the second power cutoff signal, and the control unit receives the main battery voltage value supplied from the vehicle power supply unit. This can be achieved by a sudden start prevention device that determines whether sudden start is made after the main battery voltage value exceeds the second threshold or after the engine rpm value exceeds the third threshold.

Here, the second threshold is a voltage detected at the beginning of starting the vehicle and means a voltage higher than the main battery voltage value in a normal operating state outside of the idling state, and the third threshold is a voltage detected in the initial idling state when starting the vehicle. This refers to the rpm that appears higher than the stable rpm in normal operation after idling.

According to the sudden start prevention device and sudden start prevention method according to the present invention, it can be easily implemented with a simple circuit and can be installed within the cabin without the need for installation on the bonnet. It can also be provided as an after-market product and is installed and operated independently of the vehicle's internal communication network, making it possible to reliably prevent sudden vehicle acceleration.

When the sudden start prevention device and sudden start prevention method according to the present invention are applied to an electric vehicle, it is possible to prevent a sudden high current from flowing to the vehicle's driving motor, thereby preventing fires that frequently occur in electric differential vehicles. Additional effects can be obtained.

1 is a connection diagram of a vehicle internal communication network including a gateway and an ECU connected thereto.
Figure 2 is a block diagram of a sudden start prevention device as an embodiment according to the present invention.
Figure 3 is a schematic diagram showing how electricity is supplied to each part of the vehicle in an internal combustion engine vehicle equipped with an engine.
Figure 4 is a configuration diagram of a sudden start prevention device as an embodiment according to the present invention.
Figure 5 is a configuration diagram of a sudden start prevention device as an embodiment according to the present invention.
Figure 6 is a specific implementation example of the first power switch shown in Figure 5.
Figure 7 is a configuration diagram of a sudden start prevention device according to an embodiment of the present invention applied to an electric vehicle.
Figure 8 is a process flow chart for preventing sudden oscillation by resetting the power using the sudden oscillation prevention device according to the present invention.
Figure 9 is a process flow chart for preventing sudden oscillation by turning off the power using the sudden oscillation prevention device according to the present invention.
Figure 10 is a process flow chart for preventing sudden start through power reset by applying the sudden start prevention device according to the present invention to an electric vehicle.

The terms used in this specification are merely used to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

In addition, in this specification, “on or above” means located above or below the target portion, but this does not necessarily mean located above the direction of gravity. That is, “on or above” as used herein includes not only the case of being located above or below the target part, but also the case of being located in front or behind the target part.

Additionally, when a part of a region, plate, etc. is said to be “on or above” another part, this does not only mean that it is in contact with or at a distance “directly on or above” another part, but also that there is another part in between. Also includes cases where there are.

In addition, in this specification, when a component is referred to as "connected" or "connected" to another component, the component may be directly connected or directly connected to the other component, but specifically Unless there is a contrary description, it should be understood that it may be connected or connected through another component in the middle.

Additionally, in this specification, terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another.

First, let's define a cabin. Typically, a cabin refers to the space where passengers, including the driver, stay inside a vehicle. In the present invention, the cabin is defined as the extent to which passengers, including the driver, can work inside the vehicle with the vehicle door closed. For example, in the present invention, 'work is possible in the cabin' should be understood to include work by tearing off the dashboard while the worker stays in the cabin with the vehicle door closed. In contrast, work performed outside the vehicle by a worker opening the vehicle door should be understood as work outside the scope of work possible within the cabin.

A car equipped with an internal combustion engine can only be driven by supplying a mixture (a mixture of fuel and air) to the cylinder, determining the ignition time, and maintaining the engine start. Afterwards, when the driver operates the accelerator and brake, the speed and torque are adjusted through accelerator and brake signal processing, and the vehicle operates through a series of repetitions of operations ranging from driving to stopping. Therefore, even if sudden acceleration (when the engine rotates abnormally quickly) occurs under normal conditions, it does not cause a major problem as long as it can be controlled with the mixture and brake force.

Analysis of the EDR (Event Data Recorder) data of the vehicle that caused the sudden acceleration accident shows that the accelerator is maintained at close to 100% and the brake switch is in the OFF state. When the accelerator is close to 100%, it means that under normal driving conditions, the driver is fully accelerator (the driver has pressed the accelerator as deeply as possible), and when the brake switch is OFF, it means that under normal driving conditions, the driver is pressing the accelerator as deeply as possible. This shows that the brakes are not being operated. Based on this EDR data, the vehicle manufacturer submits it as evidence that the driver incorrectly operated the accelerator instead of the brake, thereby proving that sudden acceleration did not occur, and there are frequent cases where the accident is treated as an accident caused by the vehicle driver's inexperience in operation.

However, by checking the driver's testimony and black box audio, it can be seen that when sudden acceleration occurs, most drivers take their foot off the accelerator and repeat the action of operating the brake. Nevertheless, the vehicle does not respond to the driver's manipulations, and data is recorded in the EDR as if it is sprinting without applying the brakes while fully accelerator. It is nearly impossible to determine what caused this sudden eruption. Additionally, it tends to occur more frequently in high-performance cars equipped with more electronic equipment.

So far, vehicle manufacturers and experts have proposed various methods and systems to identify or prevent sudden acceleration, but it is understood that they are unable to properly prevent it because they are attempting to control it using the vehicle's internal communication network.

For vehicle safety and driver convenience, multiple ECUs (Electronic Control Units) are installed in the vehicle, and these multiple ECUs communicate through the CAN (Controller Area Network) protocol, a representative vehicle internal communication network. ECUs are wired to CAN Bus and send and receive messages to each other in a broadcasting manner.

Vehicles are equipped with many ECUs (Electronic Control Units). All electronically controlled functions, such as smart keys, digital dashboard, ABS brakes, automatic headlights, automatic air conditioning, engine control, and cruise control, are controlled through each ECU, and the ECM (Engine Control Module) that controls the engine, brakes, etc. Numerous ECUs are used, including the BCM (Brake Control Module) that controls the airbag and the ACU (Airbag Control Unit) that controls the airbag. In terminology, the ECU that controls the engine is called ECM, but ECM is a term used in the automobile industry to distinguish it from other ECUs, and in the present invention, the module that controls the engine is called 'engine ECU' to unify the terminology.

In order to increase the amount of data and improve communication speed due to the use of numerous ECUs, communication is performed by dividing into multiple CAN Buses through a gateway as shown in Figure 1. Separated CAN Buses are called CAN Channels. In general, the C-CAN (Chassis CAN) channel where the ECUs in charge of the chassis communicate, the P-CAN (Powertrain CAN) channel where the powertrain-related ECUs are connected, and the B-CAN channel where the body-related ECUs are connected. It can be classified into CAN (Body CAN) channels, etc. As shown in Figure 1, a plurality of input devices (e.g., APS, Throttle Position Sensor (TPS)) and output devices (e.g., hydraulic pump) are connected to the vehicle's internal communication network to detect or control the status of the vehicle.

In the present invention, for convenience of explanation, devices connected to the vehicle's internal communication network as shown in FIG. 1 will be referred to as 'internal communication network devices' 200, and devices not connected to the vehicle's internal communication network will be referred to as 'external communication network devices'. do.

The inventor of the present application understands that the conventional technologies for solving sudden oscillation so far have not been able to solve the problem because they attempted to identify sudden oscillation by receiving data from such an internal communication network device when a sudden oscillation occurs in a vehicle and control the sudden oscillation using an internal communication network device. . This is because when a sudden oscillation occurs, error data is generated in the internal communication network, and devices linked to this error data operate abnormally, making control no longer possible. However, since conventional technologies were designed to prevent sudden acceleration by using such internal communication network devices, it was practically difficult to prevent sudden acceleration.

The sudden start prevention device or sudden start prevention method according to the present invention does not connect to the vehicle's internal communication network or receives only data through minimal connection, so it can respond quickly by determining whether there is a sudden start. In addition, the sudden start prevention device according to the present invention does not use error data generated in the vehicle's internal communication network due to sudden start, but receives data from a separate external communication network device and then stops the vehicle operation through a separate control line and data stored in the engine ECU. After forcibly deleting the , allow the vehicle to operate normally again.

Figure 2 is a configuration diagram of a sudden start prevention device as an embodiment according to the present invention. The sudden acceleration prevention device 100 according to the present invention includes an accelerator detection sensor 110 implemented as an external communication network device, a control unit 120, a power switch 130 and a display unit 140 that operate according to the output signal of the control unit 120. It consists of

The accelerator detection sensor 110 is a sensor that outputs a value (accelerator output value) that changes depending on the degree to which the driver steps on the accelerator. Existing vehicles are also equipped with one or more accelerator detection sensors 210 that are connected to the vehicle's internal communication network 240. The sudden start prevention device 100 according to the present invention is different in that it is provided with a separately added accelerator detection sensor 110 that operates independently and is not connected to the vehicle's internal communication network. If only one accelerator detection sensor 110 is provided, it may break down due to wear and tear due to use, so it goes without saying that two or more accelerator sensors 110 can be installed to prepare for such cases. The accelerator detection sensor 110 can be implemented using an Accelerator Pedal Sensor (APS). APS is also called acceleration position sensor. The accelerator detection sensor 110 according to the present invention is installed on the accelerator pedal exposed to the driver's seat of the vehicle, but is not connected to the vehicle's internal communication network bus (for example, CAN bus) but is directly connected to the control unit 120 proposed in the present invention. It is installed.

The power switch 130 can be implemented as a relay switch that is turned off/on by a power cutoff signal or power connection signal supplied from the control unit 120. Of course, the power switch 130 can be implemented as a plurality of individual power switches that are individually operated to turn off/on the power supplied to a plurality of vehicle parts, respectively.

The display unit 140 is a device that visually or audibly displays to the driver whether the vehicle is in a normal driving state or a sudden acceleration has occurred. The display unit 140 can be implemented with an LED, speaker, or LCD. When the display unit 140 is implemented as an LED, it can be displayed by periodically emitting green light when the vehicle is in normal operation, and by lighting up red when sudden acceleration occurs. When the display unit 140 is implemented with a flat panel device such as an LCD, various information can be displayed in addition to information about whether the vehicle is in a normal driving state or a sudden acceleration has occurred. That is, of course, various data (speed, rpm, battery voltage, etc.) that can be received from the vehicle's internal communication network can be displayed through the display unit 140. Since various data received through the vehicle's internal communication network are used only for display purposes through the display unit 140, they do not affect sudden acceleration control.

The control unit 120 can be obtained using an accelerator output value input from an accelerator detection sensor installed as an external communication network device and data input from an OBD terminal connected to an internal communication network device, or can be calculated using data input from the OBD terminal. The presence of sudden acceleration is determined using the engine rpm value, fuel injection amount, and engine load value. If it is determined that sudden acceleration is occurring, the control unit 120 generates a power cutoff signal that simultaneously cuts off all power supplied to the vehicle, or generates a power reset signal that simultaneously cuts off all power supplied to the vehicle and then supplies it again after a first time. This is the circuit part that does. As shown in FIG. 2, the control unit 120 is also implemented as an external communication network device that operates independently without being connected to the vehicle's internal communication network. Therefore, if the sudden start device according to the invention malfunctions, it can be removed without affecting the vehicle's internal communication network, so it does not affect the normal operation of the vehicle. In addition, in order to prevent the sudden start device according to the present invention from generating a signal during normal driving, the circuit that processes the power cut signal or power reset signal is applied as a Normal Open Circuit that maintains an open state.

The sudden start prevention device according to the present invention is implemented so that when it is determined that sudden start has occurred, (1) it only performs the operation of cutting off the power supplied to the vehicle, and then the operation of restarting the vehicle is performed by the driver (hereinafter referred to as 'blocking method'). (hereinafter referred to as the 'reset method') or (2) can be implemented by cutting off the power supplied to the vehicle for a first time and then supplying it again. Implementing the blocking method has the advantage of allowing the driver to intuitively feel that the vehicle has stopped due to sudden acceleration, but it has the inconvenience of requiring the driver to restart the engine himself. Implementing the reset method has the advantage of not requiring the driver to start the engine directly, but has the disadvantage of not recognizing it and passing it by even if sudden acceleration occurs.

Since the blocking method can be implemented more easily than the reset method, the present invention will be described in more detail based on the reset method.

The first time can be defined as the minimum time to reset all internal communication network devices by simultaneously blocking all power supply lines connected to the vehicle power supply for a certain period of time, and may have different values for each vehicle. The first time for most vehicles is understood to be less than 2 seconds. When sudden oscillation occurs, error data is accumulated on the vehicle's internal communication network bus (for example, CAN bus), and various ECUs receive and operate the error data, so it is assumed that sudden oscillation occurs. For this reason, it is necessary to remove all data on the vehicle's internal communication network bus the moment it is determined that sudden acceleration has occurred. Removing all data on the vehicle's internal communication network bus is possible by simultaneously cutting off all power supply to the bus. Therefore, of course, the first time can be defined as the minimum time to delete data existing on the vehicle's internal communication network bus.

Specifically, in order to implement the reset method, a timer is provided inside the control unit 120, and the timer is used to turn off (off) the power switch 130 installed on the power supply line that supplies power to the vehicle from the vehicle power unit. ) and then a power reset signal that is turned on again after a first time can be generated. The power reset signal can be understood as consisting of a power cutoff signal that simultaneously turns off the power switch 130 and a power connection signal that turns it back on after a first time.

In normal driving conditions, when the accelerator output value increases, the engine rpm increases linearly within the range of allowable fuel injection amount according to the engine load value (range designed by the vehicle manufacturer), and the vehicle speed also increases according to the rpm. On the other hand, when sudden acceleration occurs, a fuel injection amount exceeding the allowable fuel injection amount according to the engine load value is injected into the engine, and the accelerator output value and engine rpm show non-linear characteristics. More precisely, when sudden acceleration occurs, the accelerator output value remains almost unchanged (it may increase or decrease slightly), but when fuel injection exceeding the fuel injection amount range according to the normal engine load value is injected into the cylinder, the rpm rises sharply. occurs. In the present invention, whether sudden acceleration is determined by identifying this state.

According to the present inventor's analysis, in the case of EDR data of a vehicle that caused a sudden acceleration accident, the value of the TPS (Throttle Position Sensor, internal communication network device) transmitted to the ECU rapidly changed close to 100%, regardless of whether the driver actually stepped on the accelerator pedal. status was analyzed. In other words, even though the accelerator sensor (external communication network device) is almost unchanged, the vehicle speed and engine rpm remain high, or the displacement (%) of the TPS (internal communication network device) remains high. It has been done. As some examples, the control unit 120 may cause the engine rpm value to rise rapidly in a short period of time even though the accelerator output value is maintained within a certain range. If the engine rpm value maintains a high value even though the accelerator output value maintains a low value, or if the amount of change in the accelerator output value and the amount of change in engine rpm per unit time are outside a certain range, it can be judged as sudden acceleration. Using the sudden start prevention device presented in the present invention, it is possible to determine whether a case is a sudden start without difficulty through various sudden start accidents that have occurred in the past.

According to the present inventor's analysis, in a car with an engine that uses unleaded gasoline as fuel in normal driving conditions, the amount of change in the accelerator detection sensor and the change in engine speed (rpm) are approximately 1:70 within the fuel injection amount range according to the engine load value. It was found to show a linear coefficient. To explain in more detail, the state in which the driver does not step on the accelerator at all is called 1% (the reason it is assumed to be 1% instead of 0% is to avoid division by 0 for internal calculations), and the state in which the driver does not step on the accelerator at all is called 1%. Assuming that is 100%, if the degree of pressing the accelerator changes between 1% and 100%, the rpm changes linearly between 0 and 7,000 rpm. For example, if the driver steps on the accelerator at about 20%, the rpm will show a value of approximately 1,400.

As described above, this correlation is valid when the fuel injection amount is within the range according to the engine load value. Even if the transmission is in neutral and full accelerator is applied, vehicle manufacturers design the maximum rpm to be limited to prevent engine overload. In other words, vehicle manufacturers are limiting the maximum fuel injection amount when the engine load value is close to '0'. In contrast, when the vehicle is fully loaded and goes up a steep hill (when the engine load is high), the design is designed so that a high rpm is applied even when the vehicle speed is low. Therefore, the fuel injection amount according to the engine load value is determined, and sudden acceleration is determined using whether the change amount of the accelerator detection sensor and the change amount of engine rotation speed (rpm) are within a certain linear coefficient range. In reality, there is no case where the engine load value is '0', and this is only a theoretical value for explanation. For example, even when the transmission is in a neutral state, a load is applied to the engine, and the engine load value applied at this time is set differently for each vehicle.

On the other hand, when sudden acceleration occurs, it shows characteristics that deviate from this linear coefficient, so the relative coefficient of accelerator displacement and engine speed displacement exceeds the 1:70 range and exceeds the first threshold (for example, 1:200). It can be determined that Meanwhile, it was found that engine vehicles using diesel fuel have a linear coefficient of 1:50 to 1:60 under normal driving conditions.

For example, in the present invention, the calculation coefficient is obtained by dividing the change in rpm per unit time by the change in Excel output value per unit time using Equation 1, and if the calculation coefficient exceeds the first threshold, it can be determined that it is sudden acceleration. However, in Equation 1, the parent 'unit time' When the 'change amount of Excel output value' is arithmetically '0', the calculation coefficient is calculated by setting the denominator to the minimum change amount (for example, '1') to prevent errors during the internal calculation process.

In the case of electric vehicles, the calculation coefficient must be calculated according to Equation 2 instead of Equation 1.

The method of using the calculation coefficient calculated according to Equation 1 and Equation 2 can also determine when sudden acceleration occurs in ACC (Adaptive Cruise Control) state. Typically, when the ACC button is activated at a speed of 40 km/h or higher, the vehicle automatically operates while maintaining the distance from the car in front by adjusting the speed on its own even if the driver does not operate the accelerator or brake. In ACC mode, if the car in front suddenly moves to the next lane and disappears from the front, and the distance from the car in front (hereinafter referred to as the ‘second car in front’) of the car in front that disappeared (hereinafter referred to as ‘the car in front’) is considerable. A situation arises in which an ACC vehicle suddenly accelerates to maintain a set distance from the second vehicle in front. This sudden acceleration situation occurs in ACC vehicles where the engine rpm rises relatively quickly even if the driver does not operate the accelerator. Even if there is a need to suddenly accelerate in an ACC vehicle, under normal driving conditions, the vehicle is set to accelerate gradually taking into account the impact applied to the driver, so the calculation coefficient calculated by Equation 1 does not exceed the first threshold. For this reason, the present invention can also determine sudden acceleration that occurs in ACC state.

However, if sudden acceleration is determined using the degree to which the accelerator is depressed and the linear coefficient of rpm, there is a possibility that the condition that appears when the vehicle is started can be determined as sudden acceleration. In a vehicle, when you take your foot off the accelerator and press the key on or ignition start button while pressing the brake, the engine rpm ranges from '0' to 550 to 650 rpm at idle, or about 1,000 rpm when cold (in cold winter, etc.). The rpm rises rapidly. In the case of cold driving, when the engine is turned on, the speed rises rapidly to about 1,000 rpm and is maintained for some time. When the engine oil temperature rises appropriately, the rpm drops to the normal idle rpm value. In other words, when the vehicle is started, the output value of the accelerator sensor does not change and the rpm suddenly jumps from '0rpm' to '550~650rmp' or '1,000rpm', so the output coefficient calculated according to Equation 1 exceeds the first threshold. It will happen.

The sudden start prevention device according to the present invention solves the problem by monitoring at least one of the main battery voltage and engine rpm to prevent the phenomenon that occurs during starting from being mistaken for a sudden start state.

The method of using the main battery voltage can be solved by monitoring the main battery voltage 'before and immediately after starting' and when starting is completed. The main battery voltage 'before and immediately after starting' is normally around 12.6V, and when starting is completed, the main battery voltage increases to the range of 13.8V to 15V, which is the voltage generated by the generator. Therefore, the control unit of the present invention monitors the main battery voltage and compares the correlation coefficient between the accelerator output value and the engine rpm after it exceeds the second threshold (for example, 13.5V) to determine whether sudden acceleration has occurred. Here, after the main battery voltage reaches the second threshold (for example, 13.5V), this means that the control unit uses it as a trigger signal to start determining whether or not there is a sudden oscillation state from the moment the main battery voltage reaches the second threshold. It means. In other words, if the control unit detects the main battery voltage and exceeds the second threshold, it begins to determine whether or not there is a sudden acceleration condition. This means that the main battery voltage exceeds the second threshold and then again exceeds the second threshold. Even if it is lowered, it continues to determine whether the engine is in a sudden acceleration state until the rpm drops to '0' (when the engine stops).

The method of using rpm is to start sudden acceleration monitoring (trigger signal) from the moment the rpm exceeds the third threshold (eg, 2,000). As described above, when starting, the engine rpm changes from '0' to '550~650', which is the normal idling rpm, or exceeds '1,000' when cold, and then gradually decreases to normal idling rpm. Except when cold, the rpm does not exceed the third threshold during initial idling even when the engine is started, so in normal driving conditions, even if set to monitor sudden acceleration from the moment it exceeds the third threshold, which is the rpm that is considered the reference point at which the driver steps on the accelerator and starts driving, It's okay. Even with this setting, you can prevent sudden acceleration from occurring immediately after starting the engine. If sudden acceleration occurs as soon as the engine is started, the engine rpm quickly exceeds the third threshold and rapidly soars to the red zone. Even though the accelerator output value of the accelerator detection sensor does not change, the amount of change in engine rpm exceeds the first threshold, causing sudden acceleration. It becomes possible to discern.

A more reliable way to determine that the sudden start prevention device according to the present invention does not misinterpret the phenomenon that appears during startup as a sudden start condition is to monitor the main battery voltage and engine rpm together and operate the control unit to completely exclude whether it is due to the initial start or not. It is done.

A pulse generator is attached to a car engine equipped with an internal combustion engine, and the pulse generator transmits a signal according to the engine rotation rpm in the form of a pulse signal (for convenience, referred to as an 'engine pulse signal') on the vehicle's internal communication network (CAN bus). do. These engine pulse signals are input to the engine ECU that monitors the condition of the engine, processed, and then provided to the vehicle's internal communication network and also to the ECU mounted on the instrument panel (for convenience, we will call it 'instrument panel ECU'). To be precise, CAN communication (a type of vehicle internal communication network) operates in a broadcasting communication method, so the expression that it is provided to the instrument panel ECU is not an appropriate expression. The expression that the engine pulse signal is received from the instrument panel ECU is more appropriate, but it is provided for convenience of explanation. It is decided to express it as

As described above, in the present invention, whether sudden acceleration is determined using the accelerator output value, engine rpm value, fuel injection amount, and engine load value. Among them, the accelerator output value is input from the accelerator detection sensor installed as an external communication network device, and the remaining engine rpm value, fuel injection amount, and engine load value are input from the OBD terminal or can be obtained using data input from the OBD terminal. As such, the present invention only receives data from the OBD terminal connected to the internal communication network for sudden acceleration detection and does not transmit data to the internal communication network, so it does not affect the vehicle's internal communication network.

Figure 3 is a schematic diagram of how electricity is supplied to each part of the vehicle in an internal combustion engine vehicle equipped with an engine. In the case of a typical internal combustion engine vehicle, the vehicle power unit 230 that supplies power to the vehicle consists of a main battery 231, a generator 233, and an auxiliary battery (not shown). The main battery 231 is a battery that supplies power to the starter motor and various equipment while driving when the driver starts the vehicle, and the generator 233 operates the engine piston when starting and generates electricity using the rotational force of the engine while driving. It is a device that generates and supplies it to the vehicle, main battery 231, and auxiliary battery. The auxiliary battery is a battery used for auxiliary purposes to store the vehicle settings for a certain period of time when no power is supplied to the vehicle, such as when replacing the main battery 231. The installation location is different for each vehicle, so it is not shown in the drawing. didn't Auxiliary batteries are batteries provided in relatively expensive vehicles, so they are often not provided in regular vehicles.

The power supplied from the vehicle power supply unit 230 passes through the main fuse and then is supplied to the electronic components of each vehicle (engine ECU, fuel pump, driver's window motor, etc.) through individual fuses installed in front of each vehicle component. do.

Based on Figure 3, the section that supplies power to various electronic components provided in the vehicle can be divided into 'section A', which is the section from the vehicle power unit 230 to the stage before the individual fuse, and 'section B', which is from the stage before the individual fuse to the electronic components. You can. It will be described with reference to FIGS. 2 and 3. The sudden start prevention device includes a power switch 130 on the power supply line that supplies power from the vehicle power unit 230 to vehicle parts. The power switch 130 cuts off the power supplied to the vehicle according to the power cut-off signal (①) supplied from the control unit 120, and when the power connection signal (②) is input from the control unit 120 after the first time, it turns on the vehicle. Performs an off/on operation to resupply the supplied power.

Of course, based on Figure 3, the power switch can be installed in the 'A section' or 'B section'. When installed in section A, there is an advantage that it can be implemented with a small number of power switches, but since the connection line through which a large amount of current flows must be turned on/off, the circuit price increases and the reliability of the circuit may be problematic. In comparison, when installed in section B, there is a disadvantage of having to install multiple power switches, but there is an advantage that it can be implemented with a switch that turns off/on the connection line through which a small current flows. In addition, installing the power switch in section A makes it difficult to install inside the cabin and requires the bonnet to be opened and installed from outside the cabin. However, if installed in section B, work can be done inside the cabin for most vehicles, so installation is possible at a general car center. There are possible benefits. In most vehicles, individual fuses are installed within the cabin. For this reason, it is preferable to install the sudden start prevention device 100 according to the present invention in section B, where it can be installed in the cabin. In addition, as described above, the data used to determine sudden acceleration according to the present invention uses data regarding the degree to which the accelerator is pressed (accelerator output value) and data input from the OBD terminal. Since the vehicle's OBD terminal is provided within the cabin, when the power switch is installed in section B, the sudden start prevention device 100 according to the present invention has the advantage of being able to work within the cabin.

A plurality of devices (accelerator sensor, control unit, and power switch) provided in the sudden start prevention device 100 may be designed to receive power from the vehicle power source. Another design method is to add a super capacitor, which has a longer lifespan than the vehicle's power source battery, into the sudden start prevention device 100, and all devices (accelerator detection sensor, control unit, and power switch) that make up the sudden start prevention device 100 from the super capacitor. ) can be implemented to supply power to. Supercapacitors can be used with a relatively small capacity and can be charged within a relatively short period of time, such as a few seconds or minutes, when the vehicle is started.

When the vehicle power unit 230 is designed to apply power to the sudden start prevention device 100, it is desirable to design the control unit to receive operating power from the main battery. Typically, the control unit 120 is implemented as a semiconductor chip, and since the voltage applied from the main battery fluctuates within a certain range, the control unit rectifies the voltage applied from the main battery to a constant DC voltage that does not fluctuate. Since the control unit (semiconductor chip) installed in a vehicle must operate even in harsh environments, it is usually designed to operate smoothly even in a wide driving voltage range, such as 8V to 30V. In this case, as described above, the phenomenon that appears during startup may be mistaken for sudden oscillation. To prevent this, the control unit is preferably designed to include monitoring logic that checks the output value of the voltage supplied from the main battery.

When supplying power to the sudden oscillation prevention device 100 from a separate power source such as a supercapacitor, it must be designed so that the voltage value of the main battery can be input to the control unit and monitored.

According to additional experiments by the present inventor, sudden acceleration can be prevented simply by cutting off the power supplied to the fuel pump among vehicle parts and deleting the error data accumulated in the engine ECU without the need to cut off all power supplied from the vehicle power unit 230. It was confirmed that it was possible. When the fuel pump power is turned off, the fuel supplied to the engine is cut off, allowing the vehicle to slow down and come to a gradual stop, thereby preventing a collision. As mentioned above, when sudden acceleration occurs, error data accumulates in the engine ECU, so in order to resolve the sudden acceleration situation, the error data accumulated in the engine ECU must be removed. The most reliable way to remove error data accumulated in the engine ECU is to cut off the power supplied to the engine ECU for the first time.

When sudden acceleration occurs, if only the fuel pump power is cut off and power is supplied to the engine ECU, when the driver starts the engine again, the error data that caused the sudden acceleration remains in the engine ECU, so there is a high possibility that sudden acceleration will occur again. Therefore, in order to prevent sudden acceleration, it is necessary to remove error data from the engine ECU.

Figure 4 is a configuration diagram of a sudden start prevention device as an embodiment according to the present invention. Compared to the device shown in FIG. 2, the sudden start prevention device 100 shown in FIG. 4 has a different operation of the control unit 120 and a different configuration of the power switch. When the control unit 120 determines that sudden acceleration has occurred, it outputs a power cutoff signal (①) and an engine ECU data deletion signal (②). A second power switch 133 is installed between the vehicle power source 230 and the fuel pump 237. The power cut-off signal (①) output from the control unit 120 operates the second power switch 133 to cut off the power supplied to the fuel pump 237. According to the engine ECU data deletion signal (②) output from the control unit 120, the data accumulated in the engine ECU 239 is deleted. Of course, as described above, in order to operate in a reset method rather than a cutoff method, a power connection signal in addition to the power cutoff signal can be supplied to the second power switch 133 after the first time.

Figure 5 relates to a sudden start prevention device of another embodiment according to the present invention. As described above, one of the ways to delete error data of the engine ECU is to cut off the power supplied to the engine ECU, and Figure 5 is an implementation of this. A first power switch 131 is installed between the vehicle power unit 230 and the engine ECU 239, and a second power switch 133 is installed between the vehicle power unit 230 and the fuel pump 237. The power cut-off signal (①) output from the control unit 120 operates the second power switch 133 to cut off the power supplied to the fuel pump 237, and the engine ECU data deletion signal output from the control unit 120 ( ②) operates the first power switch 131 to cut off the power supplied to the engine ECU (239). Of course, as described above, in order to operate in a reset method rather than a blocking method, a power connection signal must be transmitted to the first power switch 131 and the second power switch 1 time after transmitting the power cutoff signal and the engine ECU data deletion signal. Just supply it to (133).

In the embodiment shown in FIG. 5, the engine ECU data deletion signal (②) turns the first power switch 131 on/off, so it can be used as substantially the same signal as the power cutoff signal (①). Therefore, the control unit 120 is configured to output only the power cutoff signal (①) without outputting the engine ECU data deletion signal (②), and uses the power cutoff signal (①) to turn on the first power switch 131 and the second power supply. Of course, all switches 133 can be controlled. Such modifications can be easily made by anyone who knows only the basic theory of circuits, and should be understood as falling within the scope of the present invention.

Figure 6 is a specific implementation example of the first power switch shown in Figure 5. As shown in FIG. 3, a first fuse 190a, one of the individual fuses, is installed between the main fuse 180 and the engine ECU 239. FIG. 6 is an example in which the first fuse 190a shown in FIG. 3 is removed and a first relay switch 193a is installed in place of the first fuse 190a. The first relay switch 193a normally maintains a normally closed state as shown in FIG. 6(a), but when the engine ECU data deletion signal (②) or power cutoff signal (①) is input, it is shown in FIG. 6(b). As described above, it switches to the open state. The first relay switch 193a shown in FIG. 6 is usually called a 'B contact relay'. Of course, the second power switch can also be installed as a B contact relay. When the two are called separately, the first relay switch can be called a first B contact relay, and the second relay switch can be called a second B contact relay.

Electric vehicles that use batteries as a power source use more electronic equipment than cars that use internal combustion engines, so sudden acceleration problems are likely to occur more frequently in the future. Figure 7 is a configuration diagram of a sudden start prevention device according to an embodiment of the present invention suitable for electric vehicles. Only the differences between the sudden start prevention device shown in FIG. 2 and the sudden start prevention device for an electric vehicle shown in FIG. 7 will be described. The sudden acceleration prevention device and prevention method presented in the present invention can also be applied to electric vehicles. Since electric vehicles are equipped with a motor instead of an engine, the motor current value applied to the motor is used instead of the engine rpm value. Electric vehicles vary the vehicle speed by accelerating and decelerating the motor rotation speed in proportion to the motor current value supplied to the motor, so the motor current value to display the speed supplied to the instrument panel or cluster is used instead of the engine rpm value. It is used as a sudden acceleration discrimination signal. The part called an instrument panel in a car that uses an engine is also called a cluster in an electric car. The instrument panel and cluster are parts that show the driver the vehicle's operating status, so they can be said to be parts that provide similar functions.

Additionally, in the case of an electric vehicle, a generator is not provided, and the vehicle power supply unit 230 is comprised of the required number of batteries. In the case of an electric vehicle, the power switch 130 is installed on the power supply line that supplies power to the vehicle from the vehicle power unit 230. The power switch 130 cuts off the power supplied to the vehicle according to the power cut signal (①) of the control unit 120, and reconnects it by the power connection signal supplied from the control unit 120 after the first time. Perform all actions.

Figure 8 is a process flowchart for preventing sudden oscillation by resetting the power using the sudden oscillation prevention device according to the present invention. When the driver starts the engine, power is supplied to the sudden start prevention device according to the present invention and the main battery voltage value and/or rpm value are input (ST410). As described above, it is determined whether the initial starting state has been exited and the normal idle state has been entered using the input main battery voltage value and/or rpm value (ST420). If it is determined that the normal idle state has not been reached in step ST420, steps ST410 and ST420 are repeated while waiting for the normal idle state to be reached.

If it is determined that the normal idle state has been reached in step ST420, an output value (accelerator output value) according to the degree to which the accelerator is pressed is input (ST430). As shown in FIG. 2, etc., this accelerator output value is input from a detection sensor that detects the degree of pressing of the accelerator, which operates independently of the vehicle's internal communication network. In a separate step from the ST430 step, the engine load value, fuel injection amount, and engine rpm value are input from the OBD terminal (ST440). For most vehicles, engine load value, fuel injection amount, and engine rpm value can be directly input through the OBD terminal, but some vehicles require correction or processing using the input data. Sudden acceleration is determined using the engine load value, fuel injection amount, accelerator output value, and engine rpm value (ST450). If sudden acceleration is determined in step ST450, sudden acceleration is displayed through the display unit, and the power supplied to the vehicle is switched to the first Generates a power reset signal that is blocked for a period of time and then supplied again (ST460). When the power supplied to the vehicle according to the power reset signal is stopped for a first time and then supplied again (ST470), the vehicle returns to the normal operating state, so step ST410 is performed again. Even if it is determined that it is not a sudden acceleration at the ST450 stage, it should be performed from the ST430 stage.

Of course, steps ST430 and ST440 in FIG. 8 may be performed in a different order or performed simultaneously. In addition, steps ST430 to ST450 in FIG. 8 should be understood as being continuously and repeatedly performed in real time at very short intervals while the vehicle is running and monitored at all times.

In addition, in order to apply the ST460 step to the embodiment shown in FIGS. 4 and 5, in the ST460 step, in addition to a power reset signal that cuts off the power supplied to the vehicle for a first time and then supplies it again, an engine ECU data deletion signal must also be supplied. .

Figure 9 is a process flowchart for preventing sudden oscillation by turning off the power using the sudden oscillation prevention device according to the present invention. Since step ST450 is the same as described in FIG. 8, description is omitted. If sudden acceleration is determined in step ST450, sudden acceleration is displayed through the display unit and a power cutoff signal is generated to cut off the power supplied to the vehicle (ST560). According to the power cut signal, the power supplied to the vehicle is cut off and the vehicle stops running. To start the vehicle again, the driver can turn the ignition key or press the ignition key to start the car again.

In addition, in order to apply the ST560 step to the embodiment shown in FIGS. 4 and 5, the ST460 step must also provide an engine ECU data deletion signal in addition to a power cutoff signal that cuts off power supplied to the vehicle.

*

Unlike engine cars, electric cars can be driven as soon as the engine is turned on. Electric vehicles do not use engine oil, so initial idling to increase the temperature of the oil, like in engine vehicles, is unnecessary. Additionally, in the case of electric vehicles, significant torque can be applied to the vehicle wheels from the moment the start button is pressed. In other words, since a large torque can be generated in a short period of time, in the case of an electric vehicle, if sudden acceleration occurs immediately after turning on the engine, it can lead to a serious accident. In the present invention, in order to prevent sudden acceleration that occurs as soon as the electric vehicle is started, steps ST410 and ST420 can be removed from FIG. 8 and proceed according to the driving flow shown in FIG. 10.

Figure 10 is a process flowchart for preventing sudden start in an electric vehicle by resetting the power using the sudden start prevention device according to the present invention. When the driver presses the start button, the output value (accelerator output value) according to the degree to which the accelerator is pressed is input (ST630). As shown in FIG. 2, etc., this accelerator output value is input from a detection sensor that detects the degree of pressing of the accelerator, which operates independently of the vehicle's internal communication network. In a separate step from the ST630 step, the motor current value and motor load value applied to the motor are input (ST640). The accelerator output value, motor current value, and motor load value are used to determine whether sudden acceleration has occurred (ST650). If sudden acceleration is determined in step ST650, the display indicates that sudden acceleration has occurred and resets the power supplied to the vehicle. Generates a power reset signal (ST660). Afterwards, when the power supplied to the vehicle is stopped for a first time according to the power reset signal and then supplied again (ST670), the vehicle returns to the normal operating state, so step ST630 is performed again. Even if it is determined that it is not a sudden acceleration at ST650 stage, it should be performed starting from ST630 stage.

Of course, steps ST630 and ST640 in FIG. 10 may be performed in a different order or performed simultaneously. In addition, steps ST630 to ST650 in FIG. 10 should be understood as being continuously and repeatedly performed in real time at very short intervals while the vehicle is running and monitored at all times.

Figure 10 shows the flow of responding to sudden acceleration of an electric vehicle through power reset. If it is determined that sudden oscillation has occurred and it is resolved by turning off the power, it can be understood that the control unit generates a power cut-off signal and supplies it to the power switch instead of generating a power reset signal in step ST660, and step ST670 is omitted.

In the case of electric vehicles, it is also necessary to delete error data accumulated in the engine ECU. Therefore, it is desirable to provide an engine ECU data deletion signal in addition to the power reset signal (or power cutoff signal) in the ST650 stage.

Although preferred embodiments of the present invention have been described and illustrated above using specific terms, such terms are only for clearly describing the present invention, and the embodiments of the present invention and the described terms are in accordance with the technical spirit and scope of the following claims. It is self-evident that various changes and changes can be made without deviating from it. These modified embodiments should not be understood individually from the spirit and scope of the present invention, but should be regarded as falling within the scope of the claims of the present invention.

100: Sudden acceleration prevention device
110: Accelerator detection sensor (external communication network device)
120: control unit
130: Power switch
131: First power switch (power SW1)
133: Second power switch (power SW1)
140: display unit
180: Main fuse
190a: 1st fuse
190b: 2nd fuse
193a: first relay switch
210: Accelerator detection sensor (internal communication network device)
220: Instrument panel
225: Window motor
230: Vehicle power unit
231: Main battery
233: Generator
235: Auxiliary battery
237: Fuel pump
239: Engine ECU

Claims (1)

In the device for preventing sudden acceleration of a vehicle, including a vehicle power unit that supplies power to the vehicle, a plurality of ECUs including an engine ECU connected to the vehicle's internal communication network, a fuel pump, and an OBD terminal that provides vehicle status information,
An accelerator detection sensor that provides an accelerator output value, which is an output value depending on the degree to which the driver steps on the accelerator;
- The accelerator detection sensor is a detection sensor that is not connected to the vehicle's internal communication network and operates independently of the vehicle's internal communication network -
A control unit that determines whether sudden acceleration is performed using vehicle status information including the accelerator output value and engine rpm value input from the accelerator detection sensor, and generates a second power cut signal and an engine ECU data deletion signal if sudden acceleration is determined;
It is installed between the vehicle power source and the fuel pump and includes a second power switch that cuts off power supplied to the fuel pump according to the second power cutoff signal,
The control unit receives the main battery voltage value supplied from the vehicle power supply unit and determines whether sudden acceleration occurs after the main battery voltage value exceeds a second threshold or after the engine rpm value exceeds a third threshold.
- The second threshold is a voltage detected at the beginning of starting the vehicle and refers to a voltage higher than the main battery voltage value in a normal operating state outside of the idle state, and the third threshold is a voltage detected in the initial idling state when starting the vehicle. This refers to the rpm that appears higher than the stable rpm in normal operation after idling -
A sudden acceleration prevention device characterized by a.