KR100469076B1 - Steering force control apparatus for power steering - Google Patents

Abstract

The present invention relates to a steering force control device for power steering,

In the conventional power steering provided with a column 20 for transmitting the rotational force of the handle 10 to the input shaft of the power cylinder 30, a speed sensor 41 for detecting the vehicle speed; An ECU 40 for transmitting a control signal based on the detected value of the speed sensor 41; A controller (50) operated by a control signal from the ECU (40) to variably adjust the strength of the current; The first and second coil parts are controlled by the current strength supplied from the controller 50 to exert a frictional reaction force on the shaft 22 of the column 20, and the coils receiving current are wound in opposite directions. First and second frictions integrally formed with 61a and 61b and the first or second coil portions 61a and 61b and in close contact with the outer diameter surface of the column shaft 22 when the power is supplied to exert frictional force. A steering force control unit 60 having units 62a and 62b;

By applying appropriately sized friction reaction force to the power steering column in response to vehicle speed fluctuations, the steering characteristics are improved in such a way that the steering wheel is lightly operated at low speeds and the steering wheel operation is made heavy at high speeds. It provides a boosting effect.

Description

Steering force control device for power steering {STEERING FORCE CONTROL APPARATUS FOR POWER STEERING}

The present invention relates to a steering force control device for power steering, and more particularly, by applying a frictional reaction force of an appropriate size to the column of the power steering according to the speed change of the vehicle, the steering wheel operation is lightly performed at low speed, and the steering wheel at high speed. The present invention relates to a steering power control device for power steering that improves steering characteristics in a manner such that the operation is made heavy, thereby improving driver comfort and stability.

Power steering refers to a device that installs a hydraulic power unit (hydraulic piston) in the middle of a vehicle steering system to reduce steering force of a steering wheel by its hydraulic action. The hydraulic pressure generated by the engine driving an oil pump The method of operating using is generally used.

1 is a block diagram of a conventional power steering.

As shown in FIG. 1, the conventional power steering uses an oil pump 32 whose flow rate is controlled proportionally by the engine speed RPM to reduce the steering force of the handle 10.

However, this type of power steering uses a control structure that is affected by the engine speed, so the steering wheel is lighter at high speeds and exposed to the risk of an accident. I had a troublesome problem.

That is, when the handle 10 moves left / right in a neutral state, high pressure oil is delivered to one side of the power cylinder 30 through an orifice diameter formed in the slot portion of the valve 36. In this case, the hydraulic pressure of the oil pump 32 is increased in proportion to the rotation speed of the engine 34. Due to this structure, since the hydraulic pressure is low at low speed and parking, the power assist force (F = P * A, where P is hydraulic pressure and A is cylinder cross-sectional area) is lowered, and the power assist force is increased at high speed.

Therefore, such a conventional power steering has the advantage of lightening the steering force when the driver operates the steering wheel 10 as a whole, but has a structure in which the handle is light at high speed and the handle is heavy at low speed.

As a result, the steering wheel is light at high speeds, and thus the driver is exposed to the risk of an accident due to a sudden change in steering angle, giving an uneasy steering feeling to the driver. There was a problem.

The present invention has been made to solve the above problems, by applying a frictional reaction force of the appropriate size to the column of the power steering according to the speed change of the vehicle, the handle operation is made lightly at low speed, the handle operation is heavy at high speed It is an object of the present invention to provide a steering power control device for power steering, which improves steering characteristics in such a manner as to be achieved, thereby improving driver comfort and stability.

1 is a configuration diagram of a conventional power steering,

2 is a configuration of the power steering to which the steering force control device of the present invention is applied,

3 is a configuration diagram of a steering force control device according to the present invention,

Figure 4 is a flow chart showing the operating flow of the steering force control device according to the present invention.

<Description of Symbols for Main Parts of Drawings>

10: handle 20: column

22: column axis 30: power cylinder

32: oil pump 33: oil tank

34: engine 36: valve

38: wheel 40: ECU

41: speed sensor 42: steering angle sensor

50: controller 60: steering force control unit

61a: first coil part 61b: second coil part

62a: first friction part 62b: second friction part

63: housing 64: amplifier

The present invention for achieving the above object, in the conventional power steering provided with a column 20 for transmitting the rotational force of the handle 10 to the input shaft of the power cylinder 30, a speed sensor for detecting the vehicle speed (41); An ECU 40 for transmitting a control signal based on the detected value of the speed sensor 41; A controller (50) operated by a control signal from the ECU (40) to variably adjust the strength of the current; The first and second coil parts are controlled by the current strength supplied from the controller 50 to exert a frictional reaction force on the shaft 22 of the column 20, and the coils receiving current are wound in opposite directions. First and second frictions integrally formed with 61a and 61b and the first or second coil portions 61a and 61b and in close contact with the outer diameter surface of the column shaft 22 when the power is supplied to exert frictional force. It comprises a; steering force control unit 60 having a portion (62a, 62b).

More preferably, the steering force control unit 60 further includes an amplifier 64 that amplifies the current supplied from the controller 50 at a predetermined rate and supplies the same to the coil unit.

More preferably, the ECU 40 operates the steering force control unit 60 only when the detected value from the speed sensor 41 becomes equal to or greater than a predetermined set value.

More preferably, the ECU 40 causes the controller 50 to vary the current supplied to the steering force control unit 60 in proportion to the magnitude of the detected value from the speed sensor 41.

On the other hand, the present invention more preferably, the steering angle sensor 42 for detecting the steering angle of the handle 10 is further provided, the ECU 40 transmits a control signal based on the detection value, the detected steering angle detection When the value is within the predetermined setting range, the steering force control unit 60 is characterized in that it does not operate.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

2 is a configuration diagram of a power steering system to which the steering force control device of the present invention is applied, FIG. 3 is a configuration diagram of a steering force control device according to the present invention, and FIG. 4 is a flowchart showing an operation flow of the steering force control device according to the present invention. to be.

The present invention is configured such that the steering force of the steering wheel is controlled according to the vehicle speed by additionally providing a predetermined component without significantly changing the structure of the power steering generally applied to the related art.

Conventional power steering in the prior art, as described above, the steering wheel 10 directly operated by the driver for steering, the column for transmitting the rotational force of the handle 10 to the connection of the input shaft (Input Shaft) of the power cylinder 30 20, a power cylinder 30 that receives the rotational force of the column 20 and transmits a steering force to the wheel 38, and is driven by the rotational force of the engine 34, and one side of the piston inside the power cylinder 30. An oil pump 32 which supplies hydraulic pressure to help the steering force, and an oil tank 33 for supplying oil into the oil pump 32 and storing the oil.

The present invention further includes the following components in the basic configuration of the power steering as described above.

That is, the speed sensor 41 for detecting the vehicle speed, the steering angle sensor 42 for detecting the steering angle of the steering wheel 10, the information detected by the speed sensor 41 and the steering angle sensor 42 are determined. ECU (Electronic Controlled Unit, 40) to control by controlling the current intensity while operating by the information sent from the ECU 40, in proportion to the current intensity variably supplied from the controller 50 A steering force control unit 60 that controls the reaction force acting on the column shaft 22. Each sensor may be a general type used in an electronically controlled vehicle, and the specific type thereof is not limited to any one.

On the other hand, the steering force control unit 60 is an amplifier 64 to amplify the current supplied from the controller 50 at a predetermined ratio, the first coil portion 61a and the second coil is wound in the opposite direction mutually The outer diameter surface of the column shaft 22 is formed integrally with the coil portion 61b and the first or second coil portions 61a and 61b and moves on the vertical surface of the outer diameter surface of the column shaft 22 depending on whether power is supplied. First and second friction parts 62a and 62b in close contact with each other and exerting a frictional force, and a housing 63 which surrounds the coil part and the friction part from the outside.

Although the coil part and the friction part formed integrally therewith are shown in this embodiment as being configured by dividing the outer circumferential surface surrounding the column shaft into two parts, it is possible to operate with the same working principle in order to better adhere to the outer diameter surface of the column shaft. It can also be configured by dividing into a larger number of parts.

Next, the operation principle of the steering gear control apparatus for power steering by this invention is demonstrated in detail.

Through the configuration shown in FIG. 2, a signal input from the speed sensor 41 for detecting the speed of the vehicle and the steering angle sensor 42 for detecting the steering angle of the steering wheel 10 when the vehicle travels is ECU 40. The controller 50 controlled by the ECU 40 is located on one side of the outer diameter portion of the column shaft 22 by varying the intensity of the current generated according to the detected vehicle speed and steering angle value. The variable current is supplied to the steering force control unit 60 that is fixedly mounted to the control unit 60.

In the present invention, first, the steering force is controlled by the speed of the vehicle. Thus, the ECU 40 may control the steering force control unit 60 to operate only with the detected value of the speed sensor 41 during the above operation. At this time, since the steering force control unit 60 does not need to be operated at a low speed, the steering force control unit is controlled through the controller 50 when the speed detection value becomes a predetermined set value (for example, 50 km / h) or more. It is desirable to allow 60 to work. Such a set value may vary depending on the specification of the vehicle to which the present invention is applied, and will typically be a speed value at which the driver starts to feel uneasy steering.

In addition, the ECU 40 causes the controller 50 to vary the current supplied to the steering force control unit 60 in proportion to the magnitude of the detected value from the speed sensor 41, so that the higher the speed, the more the column axis. Allow greater frictional reaction to be applied to (22).

On the other hand, even when the steering force control unit 60 is configured to operate when the speed of the vehicle becomes greater than or equal to a predetermined set value as described above, the steering angle control is insignificant and the steering force control unit 60 needs to be operated. Since it is a waste of energy to apply the current until there is no current, the steering angle detection value detected by the steering angle sensor 42 is within a predetermined setting range (for example, the sensor value when the neutral position is 0 and the leftmost handle). It is preferable not to supply a current to the steering force control unit 60 when it is within the range of -5 to +5 when it is set to a value of -50 at the time of rotation and a value of +50 at the time of the rightmost handle rotation. As in the above case, such a setting range may be varied according to the specification of the vehicle to which the present invention is applied, and typically, the setting range will be a steering angle range in which the driver does not feel uneasy steering even if the vehicle speed increases.

Referring to the operation of the steering force control unit 60 shown in FIG. 3, the current supplied from the controller 50 is amplified proportionally to the intensity of a predetermined desired current through the amplifier 64, and the amplified current is The first and second coil portions 61a and 61b are fixed to the outer surfaces of the first and second friction portions 62a and 62b. At this time, the number of windings and the area of the coil wound on the first or second coil parts 61a and 61b are set to an appropriate value so that the required frictional force can be generated, and the winding directions of the respective coil parts are configured in opposite directions. As a result, mutual attraction acts when the current is supplied so that the friction part exerts a friction force on the column shaft.

The first friction part 62a and the second friction part 62b, which are integrally formed with the first or second coil parts 61a and 61b, are in close contact with the outer surface of the column shaft 22, and the driver may handle the handle 10. By operating the steering force required to increase the), to have a more stable steering characteristics when driving at high speeds.

On the other hand, the power cylinder 30 and the oil pump 32 may be the same as those of the conventional structure and operation principle, but the flow rate or hydraulic pressure is set higher than the conventional one so that the handle is light at low speed or parking It is preferable to construct.

Through this configuration, the problem that the steering wheel becomes lighter during high-speed driving of the vehicle can be prevented by the operation of the steering force control unit 60 mounted on the column shaft.

On the other hand, each of the specific configuration of the present invention is not limited to the embodiment described above, various modifications are possible within the scope without departing from the technical spirit of the present invention, these modifications are the technical idea claimed as rights in the present invention Of course it is included in the scope of.

Such a steering power control device for power steering of the present invention is a type of electronically controlled steering device, and by adopting a reaction force control method that accurately and proportionally accurately controls the amount of current supplied to the steering force control unit by a sensor detection value, Compared to the speed control steering system, the proper steering force can be given by detecting the speed and steering angle, and it solves the difficulty of motor control due to the sudden steering angle change, which is a problem of the conventional DC motor control system. And it solves the problem that sophisticated control is difficult when using the flow control method by a solenoid valve.

Claims (5)

delete delete delete delete (Correct) In the conventional power steering provided with the column 20 which transmits the rotational force of the handle 10 to the input shaft of the power cylinder 30, A speed sensor 41 for detecting a vehicle speed; An ECU 40 for transmitting a control signal based on the detected value of the speed sensor 41; A controller (50) operated by a control signal from the ECU (40) to variably adjust the strength of the current; The first and second coil parts are controlled by the current strength supplied from the controller 50 to exert a frictional reaction force on the shaft 22 of the column 20, and the coils receiving current are wound in opposite directions. First and second frictions integrally formed with 61a and 61b and the first or second coil portions 61a and 61b and in close contact with the outer diameter surface of the column shaft 22 when the power is supplied to exert frictional force. It is configured to include a steering force control unit 60 having a portion (62a, 62b), When the steering angle sensor 42 for detecting the steering angle of the handle 10 is further provided to transmit a control signal by the ECU 40 based on the detected value, the detected steering angle detected value is within a predetermined setting range. The steering force control device for power steering, characterized in that the steering force control unit 60 is not operated.