KR102548805B1 - Steer-By-Wire Type Steering Apparatus - Google Patents

Abstract

The present embodiments relate to a steer-by-wire steering device. According to the present embodiments, a first member coupled to either one of a steering shaft and a motor shaft and having an axial fixing groove formed on an outer circumferential surface of one side end; A fixing protrusion corresponding to the fixing groove is formed in the axial direction and coupled to the outer side of the first member, and the second member having the first support groove spaced apart in the circumferential direction on one end surface is formed, the other of the steering shaft and the motor shaft. A third member coupled to one side and having a second support groove formed at a position corresponding to the first support groove, a ball member supported and inserted into the first support groove and the second support groove, and a housing in which a steering shaft is embedded A steer-by-wire type steering device including an anti-rotation member formed in a fixed annular shape, having an axial locking groove formed on an inner circumferential surface, and coupled to outer circumferential surfaces of the second and third members may be provided.

Description

Steer-By-Wire Type Steering Apparatus}

The present embodiments relate to a steer-by-wire type steering device, and more particularly, in a steer-by-wire type steering device, when a driver generates a rotational torque that is excessive to a steering shaft than a reaction torque of a motor, rotation of a steering shaft can be prevented. It relates to a steer-by-wire steering system capable of

In general, power steering has been developed and applied to a steering device of a vehicle to provide convenience in driving operation by assisting the driver's steering wheel manipulation force. The electro-hydraulic type used and the electro-hydraulic type using only the electric power of the motor were developed and applied.

Recently, Steer By Wire (SBW) is used to steer a vehicle by using an electric motor such as a motor instead of removing a mechanical coupling device such as a steering column, universal joint, or pinion shaft between a steering wheel and a wheel. ) type steering system has been developed and applied.

However, in the case of such a steer-by-wire steering device, since there is no mechanical connection between the steering shaft and the wheels, the steering wheel rotation of the driver can rotate indefinitely, thereby reducing the driver's steering feeling.

In other words, when the rotation of the wheel reaches its maximum point (when the steering wheel or wheel is in a full turn state in a general steering system) or when the wheel hits a curb and can no longer rotate, the steering shaft does not rotate any more. There is a need to provide such information to the driver by preventing the driver from doing so.

Accordingly, the present embodiments have been devised from the above background, and in the steer-by-wire steering system, when the driver generates a rotational torque that is excessive to the steering shaft than the reaction torque of the motor, a steer-by-wire type that can prevent rotation of the steering shaft Its purpose is to provide a steering device.

In addition, the objects of the present embodiments are not limited thereto, and other objects not mentioned will be clearly understood by those skilled in the art from the following description.

According to the present embodiments, a first member coupled to either one of the steering shaft and the motor shaft and having an axial fixing groove formed on the outer circumferential surface of one side end, a fixing protrusion corresponding to the fixing groove is formed, A second member coupled to the outside and having a first support groove spaced apart from one end in the circumferential direction is formed, coupled to the other side of the steering shaft and the motor shaft, and the second support at a position corresponding to the first support groove. A third member in which a groove is formed, a ball member supported and inserted into the first support groove and the second support groove, and an annular shape fixed to a housing in which a steering shaft is embedded, and an axial locking groove is formed on the inner circumferential surface. A steer-by-wire type steering device including an anti-rotation member coupled to outer circumferential surfaces of the second member and the third member may be provided.

According to the present embodiments, in the steer-by-wire steering system, when the driver generates a rotational torque that is excessive to the steering shaft than the reaction force torque of the motor, rotation of the steering shaft can be prevented.

1 is a schematic configuration diagram of a steer-by-wire steering device according to the present embodiments;
2 is a perspective view showing a part of a steer-by-wire type steering device according to the present embodiments;
3 is an exploded perspective view showing a part of a steer-by-wire type steering device according to the present embodiments;
4 is a cross-sectional view showing a part of a steer-by-wire type steering device according to the present embodiments;
5 to 7 are front views illustrating some of the steer-by-wire type steering devices according to the present embodiments.

Hereinafter, some embodiments of the present embodiments will be described in detail through exemplary drawings. In adding reference numerals to components of each drawing, it should be noted that the same components have the same numerals as much as possible even if they are displayed on different drawings. In addition, in describing the present embodiments, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present embodiments, the detailed description will be omitted.

In addition, in describing the components of the present embodiments, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, or order of the corresponding component is not limited by the term. When an element is described as being “connected,” “coupled to,” or “connected” to another element, that element is directly connected or connectable to the other element, but there is another element between the elements. It will be understood that elements may be “connected”, “coupled” or “connected”.

1 is a schematic configuration diagram of a steer-by-wire steering device according to present embodiments, FIG. 2 is a perspective view showing a part of a steer-by-wire steering device according to present embodiments, and FIG. 4 is an exploded perspective view showing a part of a steer-by-wire steering device according to present embodiments, FIG. 4 is a cross-sectional view showing a part of a steer-by-wire steering device according to present embodiments, and FIGS. 5 to 7 are steer-by according to present embodiments It is a front view showing a part of the wire type steering device.

As shown in these drawings, the steer-by-wire steering device according to the present embodiments is coupled to either side of the steering shaft 103 and the motor shaft 123, and an axial fixing groove 141a on the outer circumferential surface of one side end ) is formed on the first member 141, a fixing protrusion 143a corresponding to the fixing groove 141a is formed, coupled to the outer side of the first member 141, and spaced apart from one end surface in the circumferential direction. It is coupled to the other side of the second member 143, the steering shaft 103 and the motor shaft 123 in which the first support groove 143b is formed, and the second support is located at a position corresponding to the first support groove 143b. The third member 145 in which the groove 145b is formed, the ball member 151 supported and inserted into the first support groove 143b and the second support groove 145b, and the housing in which the steering shaft 103 is embedded. It is formed in an annular shape fixed to and has an axial locking groove 147a formed on the inner circumferential surface and includes an anti-rotation member 147 coupled to the outer circumferential surfaces of the second member 143 and the third member 145.

In the steer-by-wire steering device according to the present embodiments, an angle sensor 105 and a torque sensor 107 are coupled to one side of a steering shaft 103 connected to a steering wheel 101, and a driver's steering wheel ( 101) When operated, the angle sensor 105 and the torque sensor 107 detecting this send electrical signals to the electronic control device 110 so that the steering shaft motor 120 and the pinion shaft motor 130 are operated.

The electronic control device 110 operates the steering shaft motor 120 and the pinion shaft motor based on the electrical signals transmitted from the angle sensor 105 and the torque sensor 107 and the electrical signals transmitted from various sensors mounted on the vehicle. (130).

The pinion shaft motor 130 slides the rack bar 111 connected to the pinion shaft 113 to perform steering of both wheels 119 through the tie rod 115 and the nuttle arm 117, and the steering shaft motor ( 120) generates a feeling of steering reaction force in the opposite direction when the driver operates the steering wheel 101 or performs steering of the steering shaft 103 during autonomous driving.

However, although the drawings in the present embodiments show that the angle sensor 105 and the torque sensor 107 are provided on the steering shaft 103 for convenience of description, steering information is transmitted to the electronic control device 110. Of course, a motor position sensor, various radars, and camera image sensors may be provided, and a detailed description thereof will be omitted below.

In this steer-by-wire steering system, since the steering shaft 103 and the pinion shaft 113 are not mechanically connected, the driver's steering wheel 101 can rotate infinitely, so that the rotation can be stopped at an arbitrary angle. mechanical limitations are required.

That is, when the rotation of the wheel 119 reaches the maximum point (when the steering wheel 101 or the wheel 119 is in a full turn state in a general steering system) or the wheel 119 hits the curb of the road and no longer rotates. If the steering shaft motor 120 outputs the steering reaction force to the maximum, the rotation of the steering shaft 103 is prevented so that this information can be provided to the driver by preventing the steering shaft 103 from rotating any further. is supposed to

In order to prevent rotation of the steering shaft 103, a first member 141 is coupled to one side of the steering shaft 103 and the motor shaft 123, and a third member 145 is coupled to the other side. The second member 143 and the ball member 151 are coupled between the 141 and the third member 145, and when a steering shaft torque equal to or greater than the reaction force torque of the motor shaft 123 is generated, the ball member 151 The rotation of the steering shaft 103 is stopped by being supported by the locking groove 147a of the anti-rotation member 147.

However, for convenience of explanation of the present invention, the first member 141 is coupled to the steering shaft 103 and the third member 145 is coupled to the motor shaft 123 as an example.

The first member 141 coupled to the steering shaft 103 has an axial fixing groove 141a formed on the outer circumferential surface of one side end, and the fixing protrusion 143a of the second member 143 is coupled to the first member 141 ) and the second member 143 are integrally rotated.

The second member 143 is formed in an annular shape, and on its inner circumferential surface, a fixing protrusion 143a corresponding to the fixing groove 141a of the first member 141 is formed in the axial direction and coupled to the outer side of the first member 141. , First support grooves 143b spaced apart in the circumferential direction are formed on one end surface of the second member 143 .

In the third member 145 coupled to the motor shaft 123, a second support groove 145b is formed at a position corresponding to the first support groove 143b of the second member 143.

Here, the first support groove 143b is formed in a conical shape in line contact with the ball member 151 in a circular shape, as shown in FIGS. 3 and 4 .

And, the second support groove (145b) is formed in a shape with both sides inclined so that the width gradually widens from the surface opposite to one end of the second member 143 to the outer circumferential surface in the radial direction, and the second member 143 The ball member 151 is supported and inserted into the first support groove 143b of and the second support groove 145b of the third member 145.

And, the anti-rotation member 147 formed in an annular shape and having an axial locking groove 147a formed on the inner circumferential surface is coupled to the outer circumferential surfaces of the second member 143 and the third member 145.

Here, the anti-rotation member 147, although not shown in the drawings, is fixed to the housing or body in which the steering shaft 103 is built in, and the first member 141, the second member 143, and the third member 145 are fixed. It is fixed without rotating regardless of rotation.

The first member 141 has an extension part 141b extending in the axial direction at one end side with respect to the central part where the fixing groove 141a is formed, and a large diameter part 141c with an enlarged diameter at the other end side. It is available.

In addition, an elastic member 149 for applying an elastic force in the axial direction is provided between the large diameter portion 141c of the first member 141 and the second member 143, so that the ball member ( 151) is supported.

In addition, the extension portion 141b of the first member 141 is provided with a coupling portion 141d having a threaded portion on the inner circumferential surface, and a through hole 145a is formed on the inside of the third member 145 to form a fastening member 148. The body portion 148b is coupled to the coupling portion 141d of the first member 141 through the through hole 145a.

In addition, a locking jaw 145c is formed on one side of the through hole 145a so that the head 148a of the fastening member 148 is supported by the locking jaw 145c, and the first member 141 and the third member 145 ), it is possible to adjust the distance between them while coupling, so that the elastic force of the elastic member 149 can be adjusted by the amount of fastening of the fastening member 148.

Accordingly, the elastic force of the elastic member 149 is set while the first member 141, the second member 143, and the third member 145 are assembled to operate coaxially.

Here, the first support groove 143b of the second member 143 and the second support groove 145b of the third member 145 may be spaced apart in the circumferential direction and provided with three or more, in this case, in the circumferential direction. By being arranged at equal intervals of the ball member 151 is to maintain a uniform support force in the axial direction.

As described above, the steer-by-wire steering device according to the present embodiments is steering when the rotation of the wheel 119 reaches the maximum point or when the wheel 119 can no longer rotate due to bumping into a curb of the road. Rotation of the shaft 103 is prevented.

That is, in a general steering situation, the elastic member 149 is compressed by a predetermined amount by the fastening member 148 to maintain the first member 141, the second member 143, and the third member 141 from the steering shaft 103. Rotational torque is transmitted to the motor shaft 123 through the member 145 .

At this time, the ball member 151 is located only in the first support groove and the second support groove 145b, as shown in FIGS. 5 and 6, but as described above, the rotation of the steering shaft 103 must be prevented, that is, the motor When excessive rotational torque equal to or greater than the reaction torque of the shaft 123 is transmitted from the steering shaft 103, the ball member 151 is moved by the rotational force of the second member 143, as shown in FIG. 7, the second support groove 145b. ) is moved to the outer side in the radial direction along both sides of the rotation prevention member 147 and is supported by the locking groove 147a of the rotation prevention member 147, so that further rotation is restricted.

That is, when the rotational torque transmitted from the steering shaft 103 to the second member 143 is excessive, the ball member 151 moves both sides of the inclined surface of the second support groove 145b by the component of the force to move in the circumferential direction. Therefore, it is moved radially outward, and at the same time, while moving from the center of the first support groove 143b to the outer periphery, the second member 143 moves in the axial direction by the difference in height, further compressing the elastic member 149. .

Conversely, when the rotational torque is reduced, the second member 143 moves in the axial direction by the restoring force of the elastic member 149 and the ball member 151 moves to the center of the first support groove 143b, and thus At the same time, the ball member 151 is separated from the locking groove 147a and returns to the second support groove 145b.

Therefore, if the elastic force of the elastic member 149 is set according to the design target value, when a torque greater than a certain torque value is transmitted, the second member 143 rotates and moves in the axial direction by the elastic force of the elastic member 149. As the radial movement of the ball member 151 is made, rotation can be prevented.

As described above, according to the present embodiments, in the steer-by-wire steering system, when the driver generates a rotational torque that is excessive to the steering shaft than the reaction torque of the motor, there is an effect of preventing the rotation of the steering shaft. .

In the above, even though all components constituting the embodiments of the present embodiments have been described as being combined or operated as one, the present embodiments are not necessarily limited to these embodiments. That is, within the scope of the purpose of the present embodiments, all of the components may be selectively combined with one or more to operate.

The above description is only illustrative of the technical idea of the present embodiments, and various modifications and variations can be made by those skilled in the art to which the present embodiments belong without departing from the essential characteristics of the present embodiments. will be. Therefore, the embodiments disclosed in the present embodiments are not intended to limit the technical spirit of the present embodiments, but to explain, and the scope of the technical spirit of the present embodiments is not limited by these embodiments. The scope of protection of the present embodiments should be construed according to the claims below, and all technical ideas within the equivalent range should be construed as being included in the scope of the present embodiments.

101: steering wheel 103: steering shaft
123: motor shaft 141: first member
143: second member 145: third member
147: anti-rotation member 148: fastening member
149: elastic member 151: ball member

Claims (11)

A first member coupled to either one of the steering shaft and the motor shaft and having an axial fixing groove formed on an outer circumferential surface of one side end;
a second member having a fixing protrusion corresponding to the fixing groove, coupled to the outer side of the first member, and having a first support groove spaced apart from one end surface in a circumferential direction;
a third member coupled to the other side of the steering shaft and the motor shaft and having a second support groove formed at a position corresponding to the first support groove;
a ball member supported and inserted into the first support groove and the second support groove;
It is formed in an annular shape fixed to a housing in which the steering shaft is built, and an axial locking groove is formed on the inner circumferential surface to be coupled to the outer circumferential surfaces of the second and third members, and when excessive rotational torque is transmitted to the steering shaft, the steering shaft The ball member moves outward in the radial direction in the first and second support grooves by the rotational force of the two members or the third member, and is supported by the locking groove to rotate the second and third members. limited anti-rotation member;
A steer-by-wire steering system including a. According to claim 1,
The steer-by-wire type steering device, characterized in that the second member is formed in an annular shape and the fixing protrusion is formed in an axial direction on an inner circumferential surface. According to claim 1,
The steer-by-wire type steering device, characterized in that the second support groove is formed to open toward the radial outer circumferential surface of the third member. According to claim 3,
The steer-by-wire type steering device, characterized in that the second support groove is formed to widen from the inner side of the second support groove to the outer circumferential surface in the radial direction. According to claim 1,
The steer-by-wire type steering device, characterized in that the first member is provided with an extension extending in an axial direction at one end side based on the central portion where the fixing groove is formed. According to claim 3,
The steer-by-wire type steering device, characterized in that the first member is provided with a large-diameter portion whose diameter is enlarged at the other end side based on the central portion where the fixing groove is formed. According to claim 6,
A steer-by-wire type steering device, characterized in that an elastic member for applying an elastic force in an axial direction is provided between the large diameter portion and the second member. According to claim 5,
Steer-by-wire steering device, characterized in that the extension portion is provided with a coupling portion formed with a threaded portion on the inner circumferential surface. According to claim 8,
The steer-by-wire type steering device, characterized in that the through hole is formed on the inside of the third member, and the fastening member is coupled to the coupling part of the first member through the through hole. According to claim 9,
A steer-by-wire type steering device, characterized in that a locking jaw is formed at one side of the through hole to support the head of the fastening member. According to claim 1,
The steer-by-wire type steering device, characterized in that three or more of the first support groove and the second support groove are respectively provided in the circumferential direction.

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