KR20230165644A - an independent steering system for a vehicle - Google Patents

Abstract

The present invention includes a knuckle supporting a hub bearing coupled to the rotation center of a wheel; a first actuator, one end of which is hinged to a first point above the knuckle and spaced apart from the rotation center axis of the wheel, and the other end of which is hinged to the body of the vehicle; a lower arm where the lower ale end of the knuckle is hinged and the other end is coupled to the body of the vehicle; and a fixed link whose one end is hinged to the upper part of the knuckle and whose other end is connected to the body of the vehicle.

Description

Independent steering system for a vehicle

The present invention relates to an independent steering device for a vehicle, and more specifically, to an independent steering device for a vehicle that can independently control the direction of all wheels of a vehicle.

In general, power steering systems have complex configurations such as pumps, gearboxes with power cylinders, and piping, and it is difficult to precisely control the steering assistance force. There is a problem in that power steering does not operate when oil is leaked, so steering is possible with a simple configuration and assistance An electric steering device using a motor was developed to enable precise control of force.

This electric steering device has a structure in which a drive link is installed on a motor to enable forward/backward movement via a ball screw, a rotation link is connected to the drive link, a tie rod is connected to the rotation link, and the tie rod is connected to the knuckle. .

Therefore, the drive link moves forward/backward according to the rotation direction of the motor, and the rotation link rotates clockwise or counterclockwise, and the tie rod connected to the rotation link is pulled or pushed to change the direction of the wheel.

However, the conventional electric steering device requires a complicated connection structure as described above and has the limitation of not being able to individually adjust the steering angle of each wheel.

Korean Patent Publication No. 10-1273111 (registered on June 3, 2013)

The present invention is intended to solve this problem, and more specifically, the purpose of the present invention is to provide a vehicle steering device that can independently adjust the steering of the wheels by installing an actuator on the knuckle connecting each wheel of the vehicle.

The present invention for achieving this purpose includes a knuckle supporting a hub bearing coupled to the rotation center of the wheel; a first actuator, one end of which is hinged to a first point above the knuckle and spaced apart from the rotation center axis of the wheel, and the other end of which is hinged to the body of the vehicle; a lower arm whose one end is hinged to the lower part of the knuckle and whose other end is coupled to the body of the vehicle; and a fixed link whose one end is hinged to the upper part of the knuckle and whose other end is connected to the body of the vehicle.

The independent steering device for a vehicle has one end hinged to a second point disposed in parallel with the first point on a horizontal line at the top of the knuckle, and the other end is coupled to the body of the vehicle, opposite to the first actuator. a second actuator operating with a directional stroke; It may further include.

The independent steering device for a vehicle includes a case in which other ends of the first actuator and the second actuator are hinged so as to be rotatable and are fixed to the body of the vehicle; It may further include.

The first actuator or the second actuator includes a piston connected to the first point or the second point, a cylinder disposed outside the piston to guide the stroke of the piston, and one end of which is connected to the case. A drive module including a module, a screw shaft rotatably disposed inside the piston, a screw nut that converts the rotational motion of the screw shaft into a linear motion of the piston, and a motor that provides rotational force to the screw shaft. It can be included.

The fixed link is disposed between the rotation center of the wheel and the first actuator along the height direction of the vehicle, one end is disposed between the first point and the second point, and the length of the first actuator or the second actuator It may be arranged to be inclined with respect to the direction.

According to the independent steering device for a vehicle according to an embodiment of the present invention,

First, it can be miniaturized by minimizing the distance of the stroke in which the two actuators operate.

Second, the structure of the steering device can be simplified by eliminating the complex link structure that was essential for the steering device.

Third, by simplifying the structure and reducing the installation space, space utilization can be increased and weight reduction can be realized at the same time.

Fourth, by having two actuators, stability can be improved in case one actuator is damaged.

Fifth, by connecting a fixed link on the rotation center line of the knuckle, the knuckle can be fixed in the front and rear directions of the vehicle, thereby increasing steering stability.

Sixth, since the camber can be adjusted using the steering device, the turning performance of the vehicle can be improved.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

The summary set forth above as well as the detailed description of the preferred embodiments of the present application set forth below may be better understood when read in conjunction with the accompanying drawings. Preferred embodiments are shown in the drawings for the purpose of illustrating the invention. However, it should be understood that the present application is not limited to the exact arrangement and means shown.
1 is a perspective view showing a vehicle equipped with an independent steering device for a vehicle according to the present invention.
FIG. 2 is a perspective view showing the independent steering device for a vehicle shown in FIG. 1.
FIG. 3 is a side view showing the independent steering device for a vehicle shown in FIG. 2.
FIG. 4 is a plan view showing the upper part of the independent steering device for a vehicle shown in FIG. 2.
FIG. 5 is a reference diagram showing the steering state of the vehicle steering device according to the operating state of the actuator shown in FIG. 4.
FIG. 6 is a side view showing the operating state of the actuator shown in FIG. 4.
FIG. 7 is an exploded perspective view showing the actuator shown in FIG. 6 disassembled.

Since the present invention can be subject to various changes and can have various embodiments, specific embodiments will be illustrated and described in the drawings.

However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all changes, equivalents, and substitutes included in the spirit and technical scope of the present invention.

Terms containing ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by the terms.

The above terms are used only for the purpose of distinguishing one component from another.

For example, the second component may be referred to as the first component without departing from the scope of the present invention, and similarly, the first component may also be referred to as the second component.

The term and/or includes any of a plurality of related stated items or a combination of a plurality of related stated items.

When a component is said to be "connected" or "connected" to another component, it is understood that it may be directly connected to or connected to the other component, but that other components may exist in between. It should be.

On the other hand, when it is mentioned that a component is “directly connected” or “directly connected” to another component, it should be understood that there are no other components in between.

The terms used in this application are only 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 application, 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.

Hereinafter, embodiments will be described in detail with reference to the attached drawings, but identical or corresponding components will be assigned the same reference numbers regardless of reference numerals, and duplicate descriptions thereof will be omitted.

FIG. 1 is a perspective view showing a vehicle equipped with an independent steering device for a vehicle according to the present invention, and FIG. 2 is a perspective view showing the independent steering device for a vehicle shown in FIG. 1.

Referring to Figures 1 and 2, the independent steering device 100 for a vehicle according to the present invention is capable of independently controlling the steering of the front wheels based on a vehicle equipped with four wheels (W), and at least two or Driving force can also be transmitted to the front wheels. Of course, the independent steering device 100 for a vehicle can be applied to a vehicle with three wheels (W) or more than four wheels (W).

First, the independent steering device 100 for a vehicle according to the present invention can adjust the rotation angle of the wheel (W) according to the direction in which the vehicle (V) travels without being mechanically connected to the steering wheel.

One side of the independent steering device 100 for a vehicle is coupled to the wheel (W) and the other side is coupled to the body of the vehicle. One side of the independent steering device 100 for a vehicle is arranged so that the wheel (W) can rotate on the outside around the hub bearing 10, and the knuckle 20 is coupled to the inside to form the hub bearing 10 and the wheel (W). Supports the combination of And, the independent steering device 100 for a vehicle is coupled to the knuckle 20 at a position outside the rotation center (c) of the hub bearing 10. A braking device 30 may be coupled to the hub bearing 10 and the knuckle 20.

FIG. 3 is a side view showing the independent steering device for a vehicle shown in FIG. 2, and FIG. 4 is a plan view showing the upper part of the independent wheel control device for a vehicle shown in FIG. 2.

3 and 4, the vehicle steering device 100 according to an embodiment of the present invention includes a knuckle 20, a first actuator 110, a second actuator 120, a case 130, and , includes a lower arm 140 and a fixed link 150. Of course, the vehicle steering device 100 may function as a steering device using only one of the first actuator 110 and the second actuator 120. In this embodiment, two actuators are provided to ensure safety in case one actuator cannot perform its function, but more precise and stable steering is achieved through the actuators 110 and 120 spaced apart from each other. It is also to implement.

The first actuator 110 has one end coupled to a first point (P1) located on one side of an imaginary vertical line passing through the rotation center (c) of the wheel (W) on the knuckle (20), and a second One end of the actuator 120 is coupled to a second point P2 located on the other side of the knuckle 20 around an imaginary vertical line passing through the rotation center c of the wheel W. The first point (P1) and the second point (P2) are preferably disposed above the knuckle 20 with respect to the rotation center (c) of the wheel (W). It is preferable that they are arranged side by side in a horizontal direction (on a horizontal line) at the top. Although not shown in the drawing, the first point P1 and the second point P2 may be arranged side by side on the knuckle 20 below the rotation center c of the wheel W. However, it is preferable that the positions of the first point (P1) and the second point (P2) in the vehicle steering device 100 are spaced apart from the rotation center (c) of the wheel on both sides in a plane.

One end of the lower arm 140 is connected to the lower part of the knuckle 20. Therefore, under the assumption that there is no change in the stroke of the actuator, the actuators 110 and 120, the knuckle 20, and the lower arm 140 can form a single link structure. At this time, it is preferable that one end of the lower arm 140 is connected to an imaginary vertical line passing from the lower part of the knuckle 20 to the rotation center c of the wheel W. Of course, the lower arm 140 may rotate in response to changes in the strokes of the actuators 110 and 120.

A portion 141 where one end of the lower arm 140 is connected to the lower part of the knuckle 20, and a portion (P1, P2) where one end of the actuators 110 and 120 are connected to the upper part of the knuckle 20. It is preferable that spherical bearings (not shown) are provided and coupled to each.

And, the fixed link 150 is hinged so that one end overlaps the rotation center of the wheel at the top of the knuckle, and the other end is coupled to the body of the vehicle. Of course, one end of the fixed link 150 may be coupled so as not to overlap the rotation center of the wheel. Although not shown in the drawing, the fixed link 150 may have a turnbuckle structure so that its length can be lengthened or shortened, and through this, the coupling distance between one end and the other end can be adjusted and then fixed.

That is, one end (P3) of the fixed link 150 is disposed between the first point (P1) and the second point (P2) at the top of the knuckle 20, and is connected to the first actuator 110 or the second actuator ( 120) is arranged to be inclined with respect to the longitudinal direction.

And, as shown in FIG. 3, the fixed link 150 is disposed between the rotation center C of the wheel and the actuator along the height direction of the vehicle. Additionally, when the lower arm 140 is disposed at the lower portion based on the rotation center (c) of the wheel, it is preferable that the fixed link 150 is disposed at the upper portion.

A case 130 is provided on the other side of each actuator 110, 120 and the lower arm 140, and the other end of the actuators 110, 120 and the lower arm 140 are connected to be rotatable on the case 130. . Case 130 may be connected to the body of the vehicle (see FIG. 1) or may be a part of the body.

Also, the first actuator 110 and the second actuator 120 can increase or decrease their strokes in the same direction to adjust the camber of the wheel. The friction coefficient of a vehicle changes according to the camber angle depending on the characteristics of the tires, and it is necessary to induce camber to improve turning performance. However, if the strokes of the first actuator 110 and the second actuator 120 increase or decrease in different directions, the steering of the wheel can be adjusted, but if the strokes of the first actuator 110 and the second actuator 120 increase or decrease in the same direction, the camber of the wheel can be adjusted. Therefore, the turning performance of the vehicle can be improved by optimizing the camber between the wheels (or tires) and the ground according to the vehicle's speed, steering angle, passenger weight, etc.

At this time, since both ends of the fixed link 150 are rotatably connected, the knuckle can be firmly supported even during the process of adjusting the camber.

FIG. 5 is a reference diagram showing the steering state of the vehicle steering device according to the operating state of the actuator shown in FIG. 4.

As shown in FIG. 5, the vehicle steering device 100 can adjust the direction of the wheel W by rotating the knuckle (see FIG. 3, 20) according to the stroke of the actuator.

For example, as shown in FIG. 5(a), the vehicle steering device 100 can drive the vehicle straight forward and backward when the first actuator 110 and the second actuator 120 are in a neutral state maintaining the same length. In addition, as shown in FIG. 5(b), when the stroke of the first actuator 110 decreases based on the neutral state and the stroke of the second actuator 120 increases, steering may be performed to turn left.

Additionally, as shown in FIG. 5(c), when the stroke of the first actuator 110 increases and the stroke of the second actuator 120 decreases based on the neutral state, a right turn can be made. Of course, the vehicle steering device 100 can control steering by operating the first actuator 110 and the second actuator 120 so that strokes of the same size increase or decrease in opposite directions.

At this time, the fixed link 150 maintains a constant distance between the knuckle 20 and the case 130, thereby preventing the actuators 110 and 120 from operating or transmitting power or impact due to irregularities. It provides a support function to prevent influence from being transmitted to the strokes of the first actuator 110 and the second actuator 120.

FIG. 6 is a side view showing the operating state of the actuator shown in FIG. 4, and FIG. 7 is an exploded perspective view showing the actuator shown in FIG. 6 in an exploded manner.

Referring to FIGS. 6 and 7, the first actuator 110 of the vehicle steering device 100 includes a piston 111 and a cylinder 112 connected to the first point P1 and the case 130 to increase or decrease the stroke. ) and a drive module 114 that provides power according to relative movement between the piston 111 and the cylinder 112 within the stroke module 113.

In the stroke module 113, one end of the piston 111 is connected to the first point P1, and one end of the cylinder 112 is connected to the case 130. The cylinder 112 is coupled to the outside of the piston 111. The piston 111 performs a linear reciprocating motion inside the cylinder 112 so that the stroke relatively increases (or the length increases) or the stroke decreases (or the length decreases).

The piston 111 has an outer peripheral surface of a substantially hollow cylindrical shape, a first fastener 1112 provided at one end is connected to the first point (P1), and a first guide surface 1113 is formed on the outer peripheral surface. . A plurality of first guide surfaces 1113 may be arranged on the outer peripheral surface along the longitudinal direction of the piston 111.

And a guide groove 1114 is formed on the inner peripheral surface of the piston 111. A plurality of guide grooves 1114 may be arranged at opposite positions on the inner peripheral surface along the longitudinal direction of the piston 111.

The cylinder 112 may have a hollow cylindrical shape into which the piston 111 is inserted. The cylinder 112 includes a detachably fastening member 112-1 on one side where the piston 111 is coupled.

The fastening member 112-1 is approximately ring-shaped, and a second guide surface 1115 is formed at a position corresponding to the first guide surface 1113. The second guide surface 1115 is arranged to face the first guide surface 1113 and can prevent the piston 111 from rotating inside the cylinder 112 and guide the direction of linear reciprocating motion.

That is, an insertion member 111-1 is provided at the end of the first guide surface 1113 of the piston 111 integrally with the piston 111, and the insertion member 111-1 is always located inside the cylinder 112. arranged to do so. At this time, the insertion member 111-1 is positioned inside the cylinder 112 while the fastening member 112-1 is coupled to the end of the cylinder 112.

For example, the coupling structure of the second guide surface 1115 and the first guide surface 1113 may be provided at a plurality of additional positions between the piston 111 and the cylinder 112.

In order to connect one end of the cylinder 112 to be rotatable at the fourth point P4 provided on the case 130, a second fastener 1116 having a hole penetrating the inside is provided. A spherical bearing is provided between the second fastener 1116 and the fourth point P4, and the second fastener 1116 is connected to enable relative rotation on the fourth point P4 on the case.

The drive module 114 is coupled to a motor (M1) that provides rotational force, a screw shaft (1141) that rotates by receiving the rotational force of the motor (M1), and a screw shaft (1141) that converts rotational motion into linear motion. The order includes a screw nut (1142).

In the drive module 114 according to an embodiment of the present invention, the motor (M1) and the screw shaft 1141 transmit driving force by belt driving. A belt is connected between the rotation axis of the motor (M1) and the pulley 1143 keyed to the screw shaft 1141, and the belt is made of a timing belt, and the drive module 114 is a precise mechanism of the screw shaft 1141. Rotation can be controlled. Of course, a pulley 1144 may also be provided on the rotation axis of the motor M1, and the pulley 1144 of the motor rotation axis and the pulley 1143 coupled to the screw shaft 1141 have different diameters depending on the reduction ratio. It can be.

At this time, the first actuator 110 includes a motor bracket 1145 connecting the cylinder 112 and the motor M1. One side of the motor bracket 1145 is connected to surround a portion of the outer peripheral surface of the cylinder 112, and the motor (M1) is coupled to the other side. Additionally, the motor bracket 1145 may be provided with a motor shield (not shown) to cover the rotation axis of the motor M1 and a portion of the belt.

The pulley 1143 coupled to the screw shaft 1141 may be located inside the cylinder 112, and in this case, the cylinder 112 may be partially opened to allow the belt to enter and exit. Inside the cylinder 112, a bearing 1147 may be provided adjacent to the area connected to the pulley 1143 to support the rotation of the screw shaft 1141.

A long hole 1148 may be formed in the area where the motor M1 is coupled to the motor bracket 1145 so that the coupling position of the motor housing M1-1 accommodating the motor therein can be adjusted. Adjusting the coupling position of the motor housing (M1-1) on the motor bracket 1145 (or the distance between the motor rotation axis and the pulley 1143) may contribute to adjusting the tension of the belt.

A screw nut 1142 is coupled to the screw shaft 1141. The screw nut 1142 is keyed to enable sliding movement on the guide groove 1114 of the piston 111, and the screw nut 1142 and the piston 111 The coupling position is fixed by the snap ring 1149.

Therefore, when the screw shaft 1141 rotates, the screw nut 1142 performs a linear reciprocating motion along the x-axis direction, and the piston 111 connected to the screw nut 1142 moves in a straight line in conjunction with the screw nut 1142. Exercise can take place. Of course, the coupling method of the piston 111 and the screw nut 1142 may be achieved through a different structure.

Since the second actuator 120 has the same structure as the first actuator 110, duplicate description will be omitted.

Therefore, according to the independent steering device for a vehicle according to an embodiment of the present invention, it can be miniaturized by minimizing the distance of the stroke in which the two actuators operate, and the complex structure of the linkage that was essential to the steering device can be eliminated. The structure according to the steering device can be simplified. By simplifying the structure and reducing the installation space, space utilization can be increased and weight reduction can be achieved. By providing two actuators, it is possible to prepare in case one actuator is damaged. Stability can be improved, and by connecting a fixed link on the rotation center line of the knuckle, the knuckle can be fixed in the front/rear direction of the vehicle, thereby increasing steering stability, and the steering device and camber can be separated, so the vehicle This has the effect of improving turning performance.

In the above, specific embodiments have been shown and described to illustrate the technical idea of the present invention, but the present invention is not limited to the same configuration and operation as the specific embodiments as described above, and various modifications may be made without departing from the scope of the present invention. It can be carried out within. Accordingly, such modifications should be considered to fall within the scope of the present invention, and the scope of the present invention should be determined by the claims described below.

100: Vehicle steering device
110: first actuator
120: Second actuator
130: case
140: Lower arm
150: Fixed link

Claims (5)

A knuckle supporting a hub bearing coupled to the rotation center of the wheel;
a first actuator, one end of which is hinged to a first point above the knuckle and spaced apart from the rotation center axis of the wheel, and the other end of which is hinged to the body of the vehicle;
a lower arm whose one end is hinged to the lower part of the knuckle and whose other end is coupled to the body of the vehicle; and
An independent steering device for a vehicle, comprising a fixed link whose one end is hinged to the upper part of the knuckle and whose other end is connected to the body of the vehicle. In claim 1,
One end is hinged to a second point arranged parallel to the first point and the horizontal line at the top of the knuckle, and the other end is coupled to the body side of the vehicle, and operates with a stroke in the opposite direction to the first actuator. second actuator;
An independent steering device for a vehicle, further comprising: In claim 2,
A case that hinges the other ends of the first actuator and the second actuator so that they can rotate and is fixed to the body of the vehicle; An independent steering device for a vehicle, further comprising: In claim 3,
The first actuator or the second actuator,
A stroke module including a piston connected to the first point or the second point, a cylinder disposed outside the piston to guide the stroke of the piston, and one end of which is connected to the case;
Comprising a drive module including a screw shaft rotatably disposed within the piston, a screw nut that converts the rotational movement of the screw shaft into a linear movement of the piston, and a motor that provides rotational force to the screw shaft. Features an independent steering device for a vehicle. In claim 2,
The fixed link is,
It is disposed between the rotation center of the wheel and the first actuator along the height direction of the vehicle,
One end is disposed between the first point and the second point,
An independent steering device for a vehicle, characterized in that it is arranged to be inclined with respect to the longitudinal direction of the first actuator or the second actuator.

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