KR20150036964A - Wheel Tire External Impairment Protection Method - Google Patents

Abstract

The present invention relates to a wheel tire external damage prevention method which determines that a wheel tire (100-1) is in contact with an object (200), and reduces or blocks a current, which is permitted to a motor (20), if ECU (10) recognizes a dramatic increase of a steering torque value of a steering apparatus where a steering occurs in a way that a current value, which is permitted to the motor (20), is adjusted when stationary steering of a vehicle under 3Kph. Then, the present invention can prevent external damage to a wheel tire (100-1) without a burden of expense due to the addition of a hardware as the steering apparatus does not deliver the steering torque which corresponds to a size of a steering torque of a driver to the wheel tire (100-1). Especially, the present invention prevents an operation fail or damage to the motor and the ECU (MCU), etc. caused by a heat load by fundamentally blocking an excessive output generation of motor driven power steering (MDPS) or electro-hydraulic power steering (EHPS) based on the motor.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to prevention of damage to an outer surface of a wheel tire, and more particularly, to prevention of damage or breakage of a wheel tires contacted with an object during steady-state steering at a vehicle speed of 3 kph or less, The present invention relates to a method for preventing external damage to a tire tire.

Generally, the tire of a vehicle is frequently replaced by an unnecessary replacement due to external damage or breakage, in addition to the normal replacement according to the durability period.

An example of external damage is a case where a tires or wheels of a stopped vehicle are in contact with a curve block that distinguishes between the roadway and the roadway, but the vehicle is not steered while the driver is not aware of his or her vision.

In such a situation, the driver's stopping steering may cause tire damage / breakage, which may cause a serious accident during driving.

In addition, the steered steering which continues in this state is a cause that the steering parts can be damaged by the excessive force generated by the booster.

Particularly, damage to the steering apparatus due to excessive steering by the driver is inevitably further intensified in the MDPS (Motor Driven Power Steering (MDPS)) type steering apparatus, unlike the HPS (Hydraulic Power Steering) type steering apparatus.

This is because the MDPS is a method in which the current values applied to the motor are adjusted according to the driving conditions of the vehicle by interposing the respective control factors in the basic current map.

Therefore, in the MDPS, high current is applied to generate large output, which generates a lot of heat in the system. The generated heat is generated by the motor, ECU (Engine Control Unit) or MCU (Motor Control Unit) It can not help but serve as a cause.

To this end, the overload protection / overpower protection (OLP / OHP) logic is applied to the MDPS to block or reduce the excessively applied current, thereby preventing failures or breakage of the MDPS components.

Korean Patent Publication No. 10-2011-0114897 (October 20, 2011)

In general, the overload protection / over heating protection (OLP / OHP) logic applied to MDPS is a logic to prevent malfunction or damage of motor or ECU (MCU) due to heat generation due to high current of MDPS. It prevents malfunction of motor or ECU (MCU) without additional hardware.

However, the OLP / OHP logic monitors the current flowing time and is activated only when a large current is continuously input over a certain period of time as a result of the monitoring.

Accordingly, when the steering torque of the driver is increased in a state in which the wheel tires or the wheel wheel are in contact with the curb block, the MDPS can not produce a larger output so as to coincide with the driving force of the driver.

Although the increase in the output of the MDPS leads to an increase in the current applied to the motor, if the OLP / OHP logic does not exceed a predetermined time in such a state, the output of the MDPS increases, ) Or failures such as failure to occur.

In particular, considering the trend that all vehicle steering systems are being switched from HPS to MDPS, failure or damage of MDPS components due to unreasonable steering operations that would occur during stopping steering is caused by the field claims of MDPS, There is a risk that it can be triggered.

As an example for solving this problem, various sensors and cameras are mounted on a vehicle, so that the driver can accurately recognize an external situation such as a wheel tire pinched and fundamentally prevent an excessive steering torque of the driver, Can be prevented.

However, the installation of various sensors and cameras in the vehicle provides convenience to the driver, but the cost is high.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems, and it is an object of the present invention to provide a steering apparatus that recognizes a sudden increase in steering torque in software in a steered state without transmitting a steering torque corresponding to a driver's steering torque magnitude to a wheel tire, In particular, it prevents the external damage of the wheel tire without any additional cost, and in particular, the motor-driven MDPS (Motor Driven Power Steering) and the EHPS (Electro-hydraulic Power Steering) And an operation failure (Failure or breakage) of an ECU (MCU) or the like is prevented.

According to another aspect of the present invention, there is provided a method for preventing external damage to a wheel tire, comprising the steps of: recognizing a sudden increase in the steering torque value of the steering apparatus during a steered state, The steering torque corresponding to the driver's steering torque magnitude is not transmitted.

The steered steering is performed when the vehicle speed condition and the steering angle condition are satisfied, the vehicle speed condition is 3 Kph or less, and the steering angle condition is 90% of steering angle end <steering angle <+ steering angle end 90%.

The sudden increase recognition of the steering torque value is detected by monitoring the torque value change, and the steep increase condition of the steering torque value is judged as a percentage (%) of the steering torque value change.

The abrupt increase condition of the steering torque value is DELTA T2 / DELTA T1 (%) >900%; T2-t1 / S2-S1 and? T2 (torque change amount (slope) at S2 to S3) = t3-t2 / S3-S2; S2 is the first elapsed time, S3 is the second elapsed time, t1 is the torque value of the reference time S1, t2 is the torque value of the reference time S2, and t3 is the torque value of the reference time S2.

The mismatch between the steering torque magnitude of the steering apparatus and the steering torque magnitude of the driver is caused by a current reduction or interruption applied to the motor that steers in a manner that the current value is adjusted, And the motor is applied to MDPS (Motor Driven Power Steering) or EHPS (Electro-hydraulic Power Steering).

The present invention prevents the steering device from transmitting a steering torque corresponding to the driver's steering torque magnitude to the wheel tires even when an excessive steering torque of the driver due to the contact or engagement of the object of the wheel tires during the steered state is achieved, There is an effect that an external damage of the tire is prevented, and in particular, a vehicle accident that may occur during driving of the vehicle in a state in which the tear or damage of the wheel tire is not recognized is prevented.

Further, according to the present invention, since the steering apparatus recognizes the sudden increase of the steering torque in the software manner by preventing the external damage of the wheel tire when the vehicle is stopped in the steady state, there is no cost required when mounting various sensors and cameras, Thereby significantly reducing the A / S cost.

Further, according to the present invention, prevention of the outer damage of the wheel tire when the vehicle is stationary is realized by reducing the steering torque of the steering apparatus, thereby preventing steering component damage to the steering apparatus.

Further, the present invention is applied to a steering apparatus in which the steering torque is reduced in order to prevent external damage to the wheel tires during steady steering and adjust the current value applied to the motor, Motor-driven power steering (EHPS) and electro-hydraulic power steering (EHPS) motors and ECUs (MCUs) are fundamentally prevented from failing or failing due to heat load due to transient current application.

In addition, the present invention does not lead to an increase in heat load due to the application of a transient current in any case when the vehicle is driven with a motor-driven MDPS (Motor Driven Power Steering) or EHPS (Electro-hydraulic Power Steering) (Field Claim) is also prevented, thereby increasing the competitive advantage in the trend that the MDPS including the hybrid vehicle is essentially installed.

FIG. 1 is an operation flow of a Curve Push Prevention Logic that can prevent an external damage of a wheel tire when the steering angle is excessively high in the MDPS according to the present invention. FIG. Fig. 3 is an operating state in which the steering apparatus does not transmit the steering torque corresponding to the driver's steering torque magnitude to the wheel tires in the torque increase state of Fig. 2, Is an example of a wheel tire external damage that may occur when the steering device transmits a steering torque that matches the driver's steering torque magnitude to the wheel tire in the torque increase state of Fig.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which illustrate exemplary embodiments of the present invention. The present invention is not limited to these embodiments.

Fig. 1 shows the operation flow of the Curb Push Prevention Logic according to the present embodiment, which can prevent damage to the outer surface of a wheel tire when the vehicle is at an excessive stop.

As shown, the ECU 10 that controls the current value of the motor 20 includes Curve Push Prevention Logic (CPPL). Therefore, the ECU 10 can be equipped with the CPPL, or can be programmed, together with all existing steering logic implemented in the MDPS.

The ECU 20 may be an MCU (Motor Control Unit). The motor 20 may be a motor for MDPS (Motor Driven Power Steering) or a motor for EHPS (Electro-hydraulic Power Steering).

In the CPPL according to the present embodiment, the vehicle speed and the steering angle for the stop steering determination are used, and the torque value for determining the torque increase amount is used. Normally, detection of vehicle speed, steering angle and torque values is included in existing logic, so their detection logic is not required in CPPL.

S10 is a procedure for detecting the vehicle speed, which can be performed in various manners, but in this embodiment, the vehicle speed sensor 30-1 is used and the ECU 10 recognizes this.

S20 is a procedure in which the steering angle is measured. This can be done in various ways, but in the present embodiment, the steering angle sensor 30-2 is used and is recognized by the ECU 10.

In S30, CPPL is executed to determine whether the vehicle is in a stopping steering condition using the vehicle speed detected in S10.

At this time, the vehicle speed <3 Kph is applied to the determination of the stopping steering condition. However, the vehicle speed can be applied at a vehicle speed in units of miles as required.

As a result of the check in S30, if the vehicle speed is> 3 Kph, the CPPL is interrupted and is switched to the stand-by mode, whereas if the vehicle speed is less than 3 Kph, the CPPL enters the next step S40.

In S40, the steering wheel operation degree of the driver is recognized as the steering angle section using the steering angle detected in S20. Thus, it is determined whether or not the stopping steering condition of the vehicle on which the CPPL is executed is satisfied.

At this time, the stopping steering condition is applied to 90% of steering angle end, 90% of steering angle end, 90% of steering angle end, and 90% of steering angle section. However, it may vary depending on the vehicle characteristics.

Subsequently, as a result of the check in S40, if the steering angle 90% <steering angle + steering angle 90% is not satisfied, the CPPL is interrupted and the mode is switched to the standby mode.

This is because, due to the characteristics of the vehicle geometry, the steering torque increase can be achieved by vehicle geometry at a steering angle of 90% or more.

Therefore, even if the wheel tires are in contact with the obstacle at 90% or more of the steering angle extremity and the driver operates the steering wheel at a steering angle of 100% in this state, the rotational displacement amount of the wheel tire is small and the rotational displacement amount of the wheel tire is small There is no fear of external damage to the wheel tires or parts of the steering apparatus.

As a result, the CPPL does not need to be executed.

On the other hand, if the result of the check in S40 is that 90% of the steering angle, 90% of the steering angle, and 90% of the steering angle are satisfied, CPPL enters the next step S50.

S50 is a procedure in which the steering torque is monitored. This can be done in various ways, but in the present embodiment, the torque sensor 30-3 is used and is recognized by the ECU 10.

S60 is a procedure in which the degree of increase / decrease of the steering torque during the steering operation is compared and determined so that when the steering operation of the driver is performed in the steered condition and the steering torque corresponding to the driver's steering torque in the steering apparatus is transmitted to the wheel tire, It is determined whether the device will transmit a steering torque that matches the driver's steering torque magnitude to the wheel tires or a steering torque that does not match the driver's steering torque magnitude.

At this time, the steering torque increase / decrease determination is applied to? T2 /? T1 (%)> 900%.

? T1 is a torque change rate during a first elapsed time from a reference time, and? T2 is defined as a torque change rate during a second elapsed time from a first elapsed time.

Fig. 2 shows an example of the steering torque increase / decrease determination.

As shown in the figure, the steering torque increase / decrease determination uses the torque-time diagram to determine the reference time S1, and the torque increase / decrease amount using the reference time S1 and the first elapsed time S2 is obtained. The first elapsed time S2 and the second elapsed time The torque increase / decrease amount using the time S3 is obtained, and these are calculated by calculating them as a percentage. Here, t1 is the torque value at the reference time S1, t2 is the torque value at the reference time S2, and t3 is the torque value at the reference time S2.

For example, the torque change amount (slope) at t1-t2 / S3-S2 = t2-t1 / S2-S1 and t2 From the result, ΔT2 / ΔT1 (%)> 900% is applied. However, it may vary depending on the vehicle characteristics.

Therefore, as a result of the check in S60, if? T2 /? T1 (%)> 900% is not satisfied, the CPPL is interrupted and is switched to the standby mode. On the other hand, when? T 2 /? T 1 (%)> 900% is satisfied, CPPL is executed, thereby preventing damage to the outer tire of the wheel tire even when the steering torque of the driver is excessively high. Breakage is prevented.

3 shows a state in which the ECU 10 controls the current value of the motor 20 in a state where? T2 /? T1 (%)> 900% is satisfied.

As can be seen from the assist torque-time diagram of the MDPS, the steering torque value is rapidly increased in the 90% interval of the vehicle stop and steering angle and steering angle end, so that it is judged as being in contact with the wheel tire and the other object (curve block) From this, it can be seen that the ECU reduces or cuts off the current applied to the motor, thereby preventing external damage to the tire tires and preventing failure or breakage of the motor or ECU of the MDPS.

On the other hand, FIG. 4 shows a state in which the ECU 10 does not control the current value of the motor 20 in a state where? T 2 /? T 1 (%)> 900% is satisfied.

The vehicle 100 moves at a speed of 3 Kph or less and the wheel tire 100-1 is in contact with or caught in the curve block 200 and the ECU of the vehicle 100 determines that the driver Is transmitted to the wheel tire 100-1.

In this case, the driver's steering torque is further increased to extract the vehicle 100, and the increase in the driver's steering torque causes an increase in the applied current of the motor by the ECU. Thus, in MDPS, To the wheel tire 100-1.

Therefore, as shown in Fig. 4 (B), the internal damage a and various external bumps (b, c) are generated in the wheel tire 100-1 in contact with the curve block 200, (100-1). In particular, the heat load of the motor due to the excessive current application is also increased, so that the failure or damage of the motor or the ECU of the MDPS is caused.

As described above, the method for preventing damage to a wheel tire according to the present embodiment is characterized in that, when the vehicle is steered at a vehicle speed of 3 Kph or less, a steep increase in the steering torque value of the steering apparatus in which steering is performed in such a manner that the current value applied to the motor 20 is adjusted It is determined that the object 200 of the wheel tire 100-1 is in contact with the motor 20 and the electric current applied to the motor 20 is reduced or cut off and the steering apparatus is controlled by the wheel tires 100-1 Of the steering torque corresponding to the driver's steering torque magnitude, thereby preventing external damage of the wheel tire 100-1 without the expense of additional hardware.

Particularly, the method of preventing damage to a wheel tire according to this embodiment fundamentally blocks the excessive output of motor-driven MDPS or EHPS (Electro-hydraulic Power Steering) Failure or breakage of the MCU or the like is prevented.

10: ECU (Engine Control Unit)
20: Motor 30-1: Torque sensor
30-2: vehicle speed sensor 30-3: steering angle sensor
100: vehicle 100-1: wheel tire
200: Curve block

Claims (9)

The steering device determines that the object is in contact with the wheel tires and does not transmit the steering torque corresponding to the steering torque magnitude of the driver to the wheel tires when the steerable steering torque value of the steering device is recognized to be suddenly increased A method of preventing damage to a wheel tire.
The method according to claim 1, wherein the stopping of steering is performed when a vehicle speed condition and a steering angle condition are satisfied.
The method according to claim 2, wherein the vehicle speed condition is a difference of 3 Kph or less, and the steering angle condition is 90% of steering angle end <steering angle <+ steering angle end 90%.
The method according to claim 1, wherein the sudden increase recognition of the steering torque value is detected by monitoring a change in torque value.
The method according to claim 4, wherein the sudden increase condition of the steering torque value is determined as a percentage (%) of the change in the steering torque value.
6. The steering control apparatus according to claim 5, wherein the sudden increase condition of the steering torque value is DELTA T2 / DELTA T1 (%) &gt;900%; T1-S2 / S1,? T2 (torque change amount at S2-S3) = t3-t2 / S3-S2; Wherein the reference value is a reference value of the reference time and the reference value is a reference value of the reference time. How to prevent tire damage.
The steering system according to claim 1, wherein the mismatch between the steering torque magnitude of the steering device and the steering torque magnitude of the driver comprises a current reduction or interruption applied to a motor that steers in a manner that the current value is adjusted. Way.
The method according to claim 7, wherein the reduction or interruption of the current applied to the motor reduces motor output.
The method according to claim 7 or 8, wherein the motor is applied to MDPS (Motor Driven Power Steering) or EHPS (Electro-hydraulic Power Steering).

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