KR101031059B1 - Steering System Equipped with Clearance Compensation Device - Google Patents

Abstract

The present invention relates to a steering apparatus having a play compensation structure.

According to an aspect of the present invention, there is provided an active steering apparatus for an automobile, comprising: an input shaft for inputting a rotational force to the gear ratio converting structure; An output shaft for outputting rotational force from the gear ratio conversion structure; A first sun gear configured at an end of the input shaft and having gear teeth on an outer circumferential surface thereof; A plurality of first planetary gears meshing with the gear teeth on the outer circumferential surface of the first sun gear; A plurality of second planetary gears circumscribed one-to-one with the first planetary gear and having an axial length longer than that of the first planetary gear and extending from the input shaft toward the output shaft; A second sun gear inscribed in all of the plurality of second planetary gears extending from the input axis in the direction of the output axis and having the same center of rotation as the first sun gear; A first planetary gear shaft which becomes a first center of rotation of the first planetary gear and extends from the first center of rotation to extend in the direction of the input axis; A second planetary gear shaft which becomes a second center of rotation of the second planetary gear and extends from the second center of rotation and extends in one end and the other end of each of the second planetary gears; A carrier to which the first planetary gear shaft and the second planetary gear shaft are fixed; And at least two second planetary gear shafts connected to each other and having an elastic force to pull the second planetary gear shaft to closely contact the second planetary gear and the first planetary gear in the direction of the first sun gear and the second sun gear. It provides an active steering device comprising an elastic body.

According to the present invention, there is provided a steering apparatus having a clearance compensation structure that reduces the noise and vibration and improves steering precision by removing the clearance of the planetary gear unit provided in the steering apparatus of the automobile.

AFS, steering, planetary, torsion bar, variable gear, active steering, elastomer

Description

Steering System Equipped with Clearance Compensation Device

1A is a schematic diagram of a planetary gear device used in a conventional active steering device;

1B is an internal front view of a planetary gear device used in a conventional active steering device;

2A is a first partial detailed view of a planetary gear device used in a conventional active steering device;

FIG. 2B is a second detailed view of a planetary gear device used in a conventional active steering device; FIG.

3A is a partial cross-sectional view of a steering force assist device having a clearance compensation structure according to a first embodiment of the present invention;

3B is a partial cross-sectional view of a steering assistance apparatus having a clearance compensation structure according to a second embodiment of the present invention;

4A is a detailed view showing a part of a steering force assist device having a clearance compensation structure according to a first embodiment of the present invention;

4B is a detailed view showing a part of a steering assistance apparatus having a clearance compensation structure according to a second embodiment of the present invention;

5 is an internal front view of a steering force assist device having a clearance compensation structure according to an embodiment of the present invention;

FIG. 6 is a detailed view showing a part of a steering force assist device having a clearance compensation structure according to a third embodiment of the present invention; FIG.

FIG. 7 is a partial detailed view of a carrier of a steering force assist device having a clearance compensation structure according to a fourth embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

100: input shaft 101: the first sun gear

102: first planetary gear 103: second planetary gear

104: second sun gear 105: first planetary gear shaft

106: second planetary gear shaft 107: output shaft

108: carrier 120: worm wheel

121: worm gear 122: drive motor

200: first play 201: second play

202: third play 333: elastic body

600: 2nd planetary gear shaft guide groove 700: 1st planetary gear shaft guide groove

The present invention relates to a steering apparatus having a play compensation structure. More specifically, the present invention relates to a steering apparatus having a clearance compensation structure that removes the clearance of the planetary gear device provided in the steering apparatus of a vehicle to reduce noise and vibration and improve steering precision.

In order to improve the safety of the car and increase the driver's convenience, various devices are installed in the car. Among them, the steering device allows the driver to freely change the direction of movement of the car when the steering wheel is turned. It is a device that assists the driver to move the car in the desired direction by arbitrarily changing the rotation center of the wheels.

To steer the wheel while the vehicle is stationary, the driver must use a greater steering force because more force must be applied than the friction between the wheel and the road surface. In particular, when the weight of the car is large, the wheels are wider, and thus the frictional force with the road surface becomes larger. In this case, a power steering system is added to allow the driver to operate the steering with a small force. The power steering system is largely divided into a hydraulically driven steering device that assists steering power by operating a hydraulic pump using engine power, and a motorized steering device using an electric motor.

The hydraulically-driven steering system senses the rotation of the steering wheel and receives the rotational force from the engine to operate the hydraulic pump and transmits the hydraulic pressure to the rack bar or the steering shaft to assist the driver's steering power.

On the other hand, the motor-driven steering device is installed on the rack or steering shaft to detect the rotation of the steering wheel to operate the motor to help the rotational movement so that the steering system operates smoothly. Motor-driven steering is largely divided into rack-driven (R-EPS) and steering-axis drive (C-EPS).

As a classification according to the method of changing the rotational movement of the steering shaft to the linear motion of the tie rod in the steering system, there are largely rack and pinion type and ball and nut type, and among these, the steering device including the rack bar and the pinion is the rack and pinion type steering. The rack-and-pinion type steering system is called a device, and the steering wheel connected to the steering wheel rotates when the driver rotates the steering wheel in the desired direction, the pinion connected to the steering shaft rotates according to the rotation of the steering shaft, and the pinion gear when the pinion rotates. The rack bar engaged with and moved in a straight direction perpendicular to the steering shaft, the rack bar transmits the force to the tie rods to have the structure so that the knuckle arm rotates around the kingpin to steer the wheels of the car. On the other hand, the ball-and-nut steering device has a structure in which a plurality of balls are inserted between the screw and the nut to transmit the rotation of the rotating shaft to the nuts by rolling contact of the balls.

Meanwhile, as the competition in the automobile market is intensifying and competition among automakers in each country is intensifying, advanced driver-oriented intelligent cars are being advanced. As one of these trends, an active steering system is applied to automobiles.

In the active steering system, a gear ratio variable mechanism is provided between the driver's handle and the steering driver. The gear ratio variable mechanism enables the vehicle to stabilize more quickly by varying the output angle to the steering input of the driver's steering wheel.

Conventionally, the technology that reduces the steering wheel steering force of the driver when the vehicle is low speed enables light and fast steering operation is already common. In a vehicle equipped with such a steering system, the steering gear ratio is constant. In this case, there are inconveniences as follows.

At low speeds, especially when parking, a lot of steering angles are required, which increases the physical burden on the driver, while it is difficult to obtain quick response when avoiding obstacles or changing to a sudden car.

In addition, when the driver is driving at a high speed, even if the driver turns the steering wheel a little, the lateral acceleration of the vehicle is rapidly increased so that the vehicle turns sharply more than necessary, thereby increasing the risk of an accident.

1A is a schematic diagram of a planetary gear device used in a conventional active steering device. As shown in the figure, the planetary gear device includes an input shaft 100, a first sun gear 101, a first planetary gear 102, a second planetary gear 103, a second sun gear 104, and a first planetary gear. And a shaft 105 and a second planetary gear shaft 106.

The first sun gear 101 is connected to the input shaft 100, and two or more first planetary gears 102 are circumscribed on the outer circumferential surface of the first sun gear 101. In addition, the first sun gear 101 and the second outer gear 103 are circumscribed on one outer circumferential surface of each first planetary gear 102. Each second planetary gear 103 has a structure that circumscribes one second sun gear 104.

As shown in the figure, when the driver rotates the steering wheel clockwise (A), the input shaft 100 and the first sun gear 101 rotate in the clockwise direction A, and the external rotation of the first sun gear 101 is performed. The first planetary gear 102 rotates in the counterclockwise direction B, the second planetary gear 103 circumscribed with the first planetary gear 102 rotates in the clockwise direction A, and the second planetary gear ( The second sun gear 104 circumscribed with the 103 is rotated counterclockwise (B). Therefore, the gear ratio of the gears constituting the planetary gear, in turn, reduces the steering power of the driver.

1B is an internal front view of a planetary gear device used in a conventional active steering device. As shown in the figure, the planetary gear device includes an input shaft 100, a first sun gear 101, a first planetary gear 102, a second planetary gear 103, a second sun gear 104, and a first planetary gear. And a shaft 105, a second planetary gear shaft 106, an output shaft 107, a carrier 108, a worm wheel 120, a worm gear 121, and a drive motor 122.

In general, the input shaft 100 and the output shaft 107 is configured on the same rotation center line, the first sun gear 101 at one end of the input shaft 100 and the second sun gear 104 at the output shaft 107. ) Is configured. As illustrated, the first planetary gear 102 is circumscribed on the outer circumferential surface of the first sun gear 101, and the second planetary gear 103 is circumscribed to the first planetary gear 102. 103 is longer than the first planetary gear 102 and extends in the direction of the output shaft 107. In addition, the second planetary gear 103 is circumscribed with the second sun gear 104.

The first planetary gear shaft 105 extends to the outside at the center of rotation of the first planetary gear 102, and the second planetary shaft extends to the outside at the center of rotation of the second planetary gear 103. Meanwhile, the first planetary gear shaft 105 and the second planetary gear shaft 106 configured as described above are configured with a carrier 108 including a function of connecting and fixing each other.

When the carrier 108 is fixed without rotation, the input shaft 100, the first sun gear 101, the first planetary gear 102, the second planetary gear 103, the second sun gear 104 and Steering force is transmitted through the output shaft 107, but the gear ratio is bound to be fixed.

As shown in the drawing, an active steering apparatus using a variable gear ratio includes a worm wheel 120, a worm gear 121, and a driving motor 122 in the carrier 108.

Thus, if the carrier 108 rotates counterclockwise (B) when the input shaft 100 rotates clockwise (A), the output shaft 107 rotates faster than when the carrier 108 is fixed. do. Also, if the carrier 108 rotates clockwise A when the input shaft 100 rotates clockwise A, the output shaft 107 rotates more slowly than when the carrier 108 is fixed. . As a result, the active steering device is activated by the rotation of the drive motor 122 under the control of the electronic control unit to rotate the carrier 108.

2A is a first partial detailed view of a planetary gear device used in a conventional active steering device. As shown in the figure, the planetary gear device includes an input shaft 100, a first sun gear 101, a first planetary gear 102, a second planetary gear 103, a first planetary gear shaft 105, and a second planetary planet. It comprises a gear shaft 106, a first play 200 and a second play 201.

One side of the first planetary gear 102 meshes with the first sun gear 101 and the other side engages with the second planetary gear 103, wherein the first play 200 and the second gear between each gear tooth. The play 201 is generated.

Gaps between gear teeth not only generate noise and vibration, but also hinder the precision of steering devices.

2B is a second partial detailed view of the planetary gear apparatus used in a conventional active steering apparatus. As shown, the planetary gear device includes a second planetary gear 103, a second sun gear 104, a second planetary gear shaft 106, an output shaft 107, and a third play 202. .

The second planetary gear 103 meshes with the second sun gear 104, and as a result, a third play 202 is generated between the gear teeth.

This clearance between the gear teeth not only generates noise and vibration, but also hinders the precision of the steering system.

In order to solve the above problems, the present invention is to provide a steering apparatus having a clearance compensation structure that eliminates the clearance of the planetary gear device provided in the steering device of the vehicle to reduce noise and vibration and improve steering precision. The purpose.

In order to achieve the above object, the present invention provides an active steering apparatus for an automobile, comprising: an input shaft for inputting a rotational force to a gear ratio converting structure; An output shaft for outputting rotational force from the gear ratio conversion structure; A first sun gear configured at an end of the input shaft and having gear teeth on an outer circumferential surface thereof; A plurality of first planetary gears meshing with the gear teeth on the outer circumferential surface of the first sun gear; A plurality of second planetary gears circumscribed one-to-one with the first planetary gear and having an axial length longer than that of the first planetary gear and extending from the input shaft toward the output shaft; A second sun gear inscribed in all of the plurality of second planetary gears extending from the input axis in the direction of the output axis and having the same center of rotation as the first sun gear; A first planetary gear shaft which becomes a first center of rotation of the first planetary gear and extends from the first center of rotation to extend in the direction of the input axis; A second planetary gear shaft which becomes a second center of rotation of the second planetary gear and extends from the second center of rotation and extends in one end and the other end of each of the second planetary gears; A carrier to which the first planetary gear shaft and the second planetary gear shaft are fixed; And at least two second planetary gear shafts connected to each other and having an elastic force to pull the second planetary gear shaft to closely contact the second planetary gear and the first planetary gear in the direction of the first sun gear and the second sun gear. It provides an active steering device comprising an elastic body.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

3A is a partial cross-sectional view of a steering force assist device having a clearance compensation structure according to a first embodiment of the present invention. As shown in the drawing, the steering assist device includes an input shaft 100, a first sun gear 101, a first planetary gear 102, a second planetary gear 103, a first planetary gear shaft 105, and a second planetary planet. And a gear shaft 106 and an elastic body 333.

One side of two or more first planetary gears 102 is circumscribed to the first sun gear 101, and a second planetary gear 103 is circumscribed to the other side of each of the first planetary gears 102. The carrier 108 has a structure in which each gear is engaged by fixing the first planetary gear shaft 105 and the second planetary gear shaft 106.

An elastic body 333 is configured to connect the second planetary gear shaft 106. The function of the elastic body 333 is to pull the second planetary gear shaft 106 with the elastic force of the elastic body 333. Therefore, the second planetary gear 103 receives a force in close contact with the first planetary gear 102 and a first planetary gear 102 also receives a force to move toward the center of the first sun gear 101.

3B is a partial cross-sectional view of a steering force assist device having a clearance compensation structure according to a second embodiment of the present invention. As shown in the drawing, the steering assist device includes a second planetary gear 103, a second sun gear 104, a second planetary gear shaft 106, an output shaft 107, and an elastic body 333.

The second sun gear 104 has a structure that is circumscribed with at least two second planetary gears 103, and the gear structure is engaged by the carrier 108 fixing the second planetary gear shaft 106 to each other.

An elastic body 333 is configured to connect the second planetary gear shaft 106. The function of the elastic body 333 is to pull the second planetary gear shaft 106 with the elastic force of the elastic body 333. Therefore, the second planetary gear 103 receives a force in the direction of the center of the second sun gear 104.

FIG. 4A is a detailed view of a part of a steering force assist device having a clearance compensation structure according to a first embodiment of the present invention. FIG. As shown in the drawing, the steering assist device includes an input shaft 100, a first planetary gear 102, a second planetary gear 103, a first planetary gear shaft 105, a second planetary gear shaft 106, and an elastic body ( 333).

By the pulling force of the elastic body 333, the second planetary gears 103 are forced to move toward the center of the first sun gear 101. Therefore, the second planetary gear 103 is in close contact with the first planetary gear 102 and the first planetary gear 102 also receives a force to be in close contact with the first sun gear 101.

As a result, the second planetary gear 103 and the first planetary gear 102 are in close contact with each other, so that the play is significantly reduced.

FIG. 4B is a detailed view of a part of a steering assistance apparatus having a clearance compensation structure according to a second embodiment of the present invention. FIG. As shown in the drawing, the steering assist device includes a second planetary gear 103, a second sun gear 104, a second planetary gear shaft 106, an output shaft 107, and an elastic body 333.

Like the first embodiment, the second planetary gears 103 are forced to be in close contact with the center of the second sun gear 104 by the pulling force of the elastic body 333. As a result, the second planetary gear 103 and the second sun gear 104 are in close contact with each other so that the play is significantly reduced.

5 is a front elevational view of a steering force assist device having a clearance compensation structure according to an embodiment of the present invention. As shown in the drawing, the steering assist device includes an input shaft 100, a first sun gear 101, a first planetary gear 102, a second planetary gear 103, a second sun gear 104, and a first planetary planet. It includes a gear shaft 105, a second planetary gear shaft 106, an output shaft 107, a carrier 108, a worm wheel 120, a worm gear 121, a drive motor 122, and an elastic body 333. do.

The elastic body 333 is configured not only on the first sun gear 101 side but also on the second sun gear 104 side to pull the second planetary gear 103 to the first planetary gear 102 side as well as the first planetary planet. The gears 102 are pulled by the first sun gear 101 so that the gear teeth of each other are in close contact with each other. Similarly, the second planetary gear 103 is pulled by the second sun gear 104 so that the gear teeth of each other are in close contact with each other.

FIG. 6 is a detailed view illustrating a part of a steering force assist device having a clearance compensation structure according to a third embodiment of the present invention. As shown in the drawing, the steering assistance apparatus includes a second planetary gear shaft 106, a carrier 108, an elastic body 333, and a second planetary gear shaft guide groove 600.

The second planetary gear shaft guide groove 600 is formed in the carrier 108 so that the second planetary gear shaft 106 moves in the center direction of the first sun gear 101. The second planetary gear shaft guide groove 600 may move the second planetary gear shaft 106 toward the center of the first sun gear 101 when the elastic body 333 pulls the second planetary gear shaft 106. Provide space.

Similarly, a second planetary gear shaft guide groove 600 is formed in the carrier 108 to move the second planetary gear shaft 106 in the direction of the center of the second sun gear 104. The second planetary gear shaft guide groove 600 may move the second planetary gear shaft 106 in the center direction of the second sun gear 104 when the elastic body 333 pulls the second planetary gear shaft 106. Provide space.

FIG. 7 is a partial detailed view of a carrier of a steering force assist device having a clearance compensation structure according to a fourth embodiment of the present invention. As shown in the drawing, the steering assistance apparatus includes a first planetary gear shaft 105, a carrier 108, and a first planetary gear shaft guide groove 700.

The first planetary gear shaft guide groove 700 is formed in the carrier 108 so that the first planetary gear shaft 105 moves in the center direction of the first sun gear 101. The second planetary gear shaft guide groove 600 may move the first planetary gear shaft 105 toward the center of the first sun gear 101 when the elastic body 333 pulls the first planetary gear shaft 105. do.

Similarly, the first planetary gear shaft guide groove 700 is formed in the carrier 108 so that the first planetary gear shaft 106 moves in the center direction of the second sun gear 104. The first planetary gear shaft guide groove 700 may move the first planetary gear shaft 106 in the center direction of the second sun gear 104 when the elastic body 333 pulls the first planetary gear shaft 106. do.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, according to the present invention, there is an effect of providing a steering apparatus having a clearance compensation structure that reduces noise and vibration and improves steering precision by removing the clearance of the planetary gear unit provided in the steering apparatus of the automobile. .

Claims (4)

In the active steering of a vehicle, An input shaft for inputting a rotational force to the gear ratio conversion structure; An output shaft for outputting rotational force from the gear ratio conversion structure; A first sun gear configured at an end of the input shaft and having gear teeth on an outer circumferential surface thereof; A plurality of first planetary gears meshing with the gear teeth on the outer circumferential surface of the first sun gear; A plurality of second planetary gears circumscribed one-to-one with the first planetary gear and having an axial length longer than that of the first planetary gear and extending from the input shaft toward the output shaft; A second sun gear inscribed in all of the plurality of second planetary gears extending from the input axis in the direction of the output axis and having the same center of rotation as the first sun gear; A first planetary gear shaft which becomes a first center of rotation of the first planetary gear and extends from the first center of rotation to extend in the direction of the input axis; A second planetary gear shaft which becomes a second center of rotation of the second planetary gear and extends from the second center of rotation and extends in one end and the other end of each of the second planetary gears; A carrier to which the first planetary gear shaft and the second planetary gear shaft are fixed; And An elastic body connecting two or more second planetary gear shafts to each other and having elasticity to pull the second planetary gear shaft to closely contact the second planetary gear and the first planetary gear in the direction of the first sun gear and the second sun gear Active steering device comprising a. The method of claim 1, The carrier provides a space for the second planetary gear shaft to move in the direction of the first sun gear by the elastic force of the elastic body and the second planetary gear shaft guide formed in the direction of the first sun gear from the second planetary gear shaft Active steering device comprising a groove. The method of claim 1, The carrier provides a space for the first planetary gear shaft to move in the direction of the first sun gear by the elastic force of the elastic body and the first planetary gear shaft guide formed in the direction of the second sun gear from the first planetary gear shaft Active steering device comprising a groove. delete

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