VEHICLE STEERING DEVICE AND VEHICLE WITH IT

Abstract

A vehicle steering device and a vehicle incorporating the same comprise a ball nut operationally coupled to a rack and configured to move the rack linearly, a first nut pulley provided on an outer surface of the ball nut and having first nut pulley teeth formed on an outer surface thereof, a second nut pulley provided on the outer surface of the ball nut and having second nut pulley teeth formed on an outer surface thereof and configured with a helix angle offset relative to a helix angle of the first nut pulley teeth, a first motor pulley of a first motor having first motor pulley teeth identical to the first nut pulley teeth, and a second motor pulley of a second motor having second motor pulley teeth.which are identical to the second teeth of the mother belt pulley.

Description

[0001] This application claims the priority and benefit of Korean patent application No. 10-2024-0184697, filed on December 12, 2024, with the Korean Intellectual Property Office, Korean patent application No. 10-2025-0026967, filed on February 28, 2025, with the Korean Intellectual Property Office, Korean patent application No. 10-2025-0026974, filed on February 28, 2025, with the Korean Intellectual Property Office, and Korean patent application No. 10-2025-0134620, filed on September 18, 2025, with the Korean Intellectual Property Office. BACKGROUND Technical area

[0002] The present disclosure relates generally to a vehicle steering device and a vehicle incorporating the same. Description of the related facts

[0003] Power steering systems are used in a vehicle's steering mechanism to provide comfort during driving by assisting the steering force exerted by the driver. Power steering systems include hydraulic power steering, which uses hydraulic pressure; electro-hydraulic power steering, which uses hydraulic pressure and engine power; and electric power steering, which uses engine power only.

[0004] A steer-by-wire (SBW) steering system was recently developed. The steer-by-wire system has no mechanical connection between the steering wheel and a wheel, such as a steering shaft, universal joint, or pinion shaft, and incorporates an electric motor for steering the vehicle.

[0005] However, if a ball nut, pulley and belt are used for the power steering or steer-by-wire steering device, problems arise in that noise can be generated during operation of the belt and, in particular, the pulley and belt must be increased in size and stiffness if a high force is required.

[0006] Since the steer-by-wire steering system has no mechanical connection between a steering shaft and a wheel, countermeasures are also required in the event of engine failure, and precise control technology is needed to control the engine.

[0007] Therefore, for a vehicle steering system and a vehicle equipped with it, there is a need for a technology that is able to reduce noise and vibrations generated by the operation of the belt, ensure high power transmission and reliably perform steer-by-wire (SBW) control. SUMMARY

[0008] Some embodiments of the present disclosure can provide a vehicle steering device and a vehicle incorporating the same, which are stable and effective in reducing noise and vibration.

[0009] According to certain embodiments of the present disclosure, a vehicle steering device may include: a ball nut coupled to a rack by means of a ball and configured to displace the rack in an axial direction as it rotates; a first nut pulley provided on an outer circumferential surface of the ball nut and having first nut pulley teeth formed on an outer circumferential surface thereof; a second nut pulley provided on the outer circumferential surface of the ball nut and having second nut pulley teeth formed on an outer circumferential surface thereof and configured to be displaced by a predetermined angle with respect to a helix angle of the first nut pulley teeth;a first motor pulley provided on a first motor and having first motor pulley teeth formed on an outer circumferential surface thereof and identical to the first mother pulley teeth; and a second motor pulley provided on a second motor and having second motor pulley teeth formed on an outer circumferential surface thereof and identical to the second mother pulley teeth.

[0010] Additionally, in one embodiment of the present disclosure, the first nut pulley and the second nut pulley can be integrated with the outer circumferential surface of the ball nut.

[0011] Additionally, in one embodiment of the present disclosure, the first nut pulley and the second nut pulley can be integrated and coupled with the outer circumferential surface of the ball nut.

[0012] Additionally, in one embodiment of the present disclosure, the first nut pulley and the second nut pulley can be coupled to the outer circumferential surface of the ball nut.

[0013] Additionally, in one embodiment of the present disclosure, the helix angles of the first and second nut pulley teeth can be formed as positive values ​​in a clockwise direction based on a central axis of the ball nut.

[0014] Additionally, in one embodiment of the present disclosure, the helix angles of the first and second nut pulley teeth can be formed as negative counterclockwise values ​​based on a central axis of the ball nut.

[0015] Additionally, in one embodiment of the present disclosure, the helix angle of the first nut pulley teeth can be formed as a positive value clockwise based on a central axis of the ball nut, and the helix angle of the second nut pulley teeth can be formed as a negative value counterclockwise based on the central axis of the ball nut.

[0016] Additionally, in one embodiment of the present disclosure, the helix angle of the first nut pulley teeth can be formed as a negative counterclockwise value based on a central axis of the ball nut, and the helix angle of the second nut pulley teeth can be formed as a positive clockwise value based on the central axis of the ball nut.

[0017] In addition, in an embodiment of the present disclosure, the first nut pulley teeth and the second nut pulley teeth can be arranged such that they are spaced apart from each other in a circumferential direction at a section where the first nut pulley and the second nut pulley adjoin each other.

[0018] Additionally, in one embodiment of the present disclosure, the first motor pulley teeth and the second motor pulley teeth can be formed such that they differ in number, and the first mother pulley teeth and the second mother pulley teeth can be formed such that they are the same in number.

[0019] Additionally, in one embodiment of the present disclosure, the first motor pulley teeth and the second motor pulley teeth can be formed such that they are the same number, and the first mother pulley teeth and the second mother pulley teeth can be formed such that they differ in number.

[0020] Additionally, in one embodiment of the present disclosure, the first motor pulley teeth and the second motor pulley teeth can be formed such that they differ in number, and the first mother pulley teeth and the second mother pulley teeth can be formed such that they differ in number.

[0021] Additionally, in one embodiment of the present disclosure, a gap in an axial direction may be provided between the first nut pulley and the second nut pulley.

[0022] Additionally, in one embodiment of the present disclosure, anti-rotation elements can be coupled between the ball nut and the first nut pulley and between the ball nut and the second nut pulley.

[0023] Additionally, in one embodiment of the present disclosure, the anti-rotation element can be integrated with the first nut pulley by forming.

[0024] Additionally, in one embodiment of the present disclosure, the anti-rotation element can be integrated with the second nut pulley by forming.

[0025] In addition, in one embodiment of the present disclosure, the anti-rotation element may include: a cylindrical section coupled to an outer circumferential surface of one end of the ball nut; and a pulley support section bent from one end of the cylindrical section, extending in a radial direction and having projecting sections arranged on an outer circumferential surface thereof and spaced apart from one another in a circumferential direction.

[0026] Additionally, in one embodiment of the present disclosure, a large-diameter section with an enlarged diameter on an outer circumferential surface thereof can be provided at one end of the ball nut, and the cylindrical section coupled to the first nut pulley can be press-fitted to the outer circumferential surface of the large-diameter section.

[0027] Additionally, in one embodiment of the present disclosure, a small-diameter section with a reduced diameter on an outer circumferential surface thereof can be provided at the other end of the ball nut, and the cylindrical section coupled to the second nut pulley can be press-fitted to the outer circumferential surface of the small-diameter section.

[0028] Additionally, an embodiment of the present disclosure may provide a vehicle comprising: a ball nut coupled to a rack by means of a ball and configured to displace the rack in an axial direction as it rotates; a first nut pulley provided on an outer circumferential surface of the ball nut and having first nut pulley teeth formed on an outer circumferential surface thereof; a second nut pulley provided on the outer circumferential surface of the ball nut and having second nut pulley teeth formed on an outer circumferential surface thereof and configured to be displaced by a predetermined angle with respect to a helix angle of the first nut pulley teeth;a first motor pulley provided on a first motor and having first motor pulley teeth formed on an outer circumferential surface thereof and identical to the first mother pulley teeth; a second motor pulley provided on a second motor and having second motor pulley teeth formed on an outer circumferential surface thereof and identical to the second mother pulley teeth; a first belt coupled to the first mother pulley and the first motor pulley; a second belt coupled to the second mother pulley and the second motor pulley; a first motor sensor configured to detect a rotational position of a shaft of the first motor; a second motor sensor configured to detect a rotational position of a shaft of the second motor;and an electronic control unit configured to take an electrical signal as an input value and to control an output value to be transmitted to the first motor and the second motor.

[0029] One embodiment of the present disclosure can provide a steering device that is stable and effective in reducing noise and vibration.

[0030] The effects of this disclosure are not limited to the effects mentioned above, and other effects not mentioned above will be obvious to a person skilled in the art from the following description.

[0031] The problems to be solved by the present disclosure, the means of achieving the problems and the effects of the above-described present disclosure do not specify any essential features of the claims, and thus the scope of the claims is not limited to the disclosure of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and other aspects, features and other advantages of the present disclosure will become clearer from the following detailed description in conjunction with the accompanying drawings: Fig. 1 and Fig. Figure 2 are schematic views that schematically illustrate a vehicle according to one embodiment of the present disclosure; Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7 to Fig. Figure 8 are partial views illustrating a vehicle steering device according to an embodiment of the present disclosure; Fig. Figure 9 is a schematic view that schematically illustrates a vehicle steering device according to an embodiment of the present disclosure; Fig. 10, Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15, Fig. 16, Fig. 17, Fig. 18 to Fig. Figure 19 are partial views illustrating a vehicle steering device according to an embodiment of the present disclosure; Fig. Figure 20 is a diagram illustrating a method for estimating a rack position according to a difference between first rotation information of a first motor and second rotation information of a second motor according to an embodiment of the present disclosure; Fig. 21 and Fig. Figures 22 are perspective partial views illustrating a vehicle steering device according to an embodiment of the present disclosure; Fig. 23, Fig. 24 to Fig. Figure 25 are cross-sectional views illustrating a vehicle steering device according to an embodiment of the present disclosure; Fig. 26, Fig. 27 to Fig. Figure 28 are partial views illustrating a vehicle steering device according to an embodiment of the present disclosure; Fig. Figure 29 is a perspective partial view illustrating a vehicle steering device according to an embodiment of the present disclosure; and Fig. Figure 30 is a perspective partial view illustrating a vehicle steering device according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF EXECUTION FORMS

[0033] In the following description of examples or embodiments of the present disclosure, reference is made to the accompanying drawings, which show, for illustrative purposes, specific examples or embodiments that can be implemented and in which the same reference numerals and symbols can be used to designate the same or similar components, even if they are shown in different accompanying drawings. Furthermore, in the following description of examples or embodiments of the present disclosure, detailed descriptions of well-known functions and components included herein are omitted where it is determined that such a description may render the subject matter rather unclear in some embodiments of the present disclosure.The terms used here, such as "including," "include," "contain," "form," "train," and "trained," are generally intended to allow the addition of other components, unless the terms are used with the term "only." As used here, singular forms are intended to include plural forms unless the context clearly indicates otherwise.

[0034] Terms such as "first," "second," "A," "B," "(A)," or "(B)" may be used here to describe elements of revelation. Each of these terms is not used to define any essentiality, order, sequence, or number of elements, etc., but is merely used to distinguish the respective element from other elements.

[0035] When it is mentioned that a first element is "connected or coupled" to a second element, "this contacted or overlapped with it," etc., it should be interpreted that the first element can not only be "directly connected or coupled" to the second element, or "this contacted or overlapped with it," but that a third element can also be "arranged" between the first and second elements, or that the first and second elements can be "connected or coupled" to each other via a fourth element, "this contacted or overlapped with it," etc. Here, the second element can be contained within at least one of two or more elements that are "connected or coupled," "contacted or overlapped," etc.

[0036] When temporally relative terms such as "after", "subsequent", "next", "before", and the like are used to describe processes or operations of elements or configurations or sequences or steps in operational, processing, or manufacturing procedures, these terms may be used to describe non-consecutive or non-sequential processes or operations unless the term "direct" or "immediate" is used together.

[0037] Additionally, if any dimensions, relative sizes, etc., are mentioned, it should be considered that numerical values ​​for an element or feature, or corresponding information (e.g., level, range, etc.), include a tolerance or error range that may be caused by various factors (e.g., process factors, internal or external influences, noise, etc.), even if a relevant description is not specified. Furthermore, the term "could" fully encompasses all meanings of the term "may."

[0038] Fig. 1 and Fig. Figure 2 are schematic views that schematically illustrate a vehicle according to an embodiment of the present disclosure. Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7 to Fig. Figure 8 are partial views illustrating a vehicle steering device according to an embodiment of the present disclosure. Fig. Figure 9 is a schematic view that schematically illustrates a vehicle steering device according to an embodiment of the present disclosure, Fig. 10, Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15, Fig. 16, Fig. 17, Fig. 18 to Fig. Figure 19 are partial views illustrating a vehicle steering device according to an embodiment of the present disclosure. Fig. Figure 20 is a diagram illustrating a method for estimating a rack position according to a difference between first rotation information of a first motor and second rotation information of a second motor according to an embodiment of the present disclosure. Fig. 21 and Fig. Figures 22 are perspective partial views illustrating a vehicle steering device according to an embodiment of the present disclosure. Fig. 23, Fig. 24 to Fig. Figure 25 are cross-sectional views illustrating a vehicle steering device according to an embodiment of the present disclosure. Fig. 26, Fig. 27 to Fig. Figure 28 are partial views illustrating a vehicle steering device according to an embodiment of the present disclosure. Fig. 29 is a perspective partial exploded view illustrating a vehicle steering device according to an embodiment of the present disclosure, and Fig. Figure 30 is a perspective partial view illustrating a vehicle steering device according to an embodiment of the present disclosure.

[0039] Fig. Figure 1 illustrates an exemplary embodiment of a vehicle equipped with a steer-by-wire steering device, and Fig. Figure 2 illustrates a vehicle equipped with a conventional steering device in which a steering shaft 103 and a rack 130 are mechanically connected. Some embodiments of the present disclosure may be based on one or both of the components shown in Figure 2. Fig. 1 and Fig. The embodiments shown in Figure 2 are used. However, for illustrative purposes only, mainly exemplary embodiments of a vehicle equipped with a steer-by-wire steering device are described below; however, certain exemplary embodiments of the present disclosure described below can be applied to a conventional steering device, for example, the one shown in Figure 2. Fig. The steering device shown in the illustrations can be used.

[0040] The vehicle according to one embodiment of the present disclosure may include a ball nut 141 which is operationally coupled to a rack 130 by means of balls 144 and is configured to move or displace the rack 130 in an axial direction by the rotation of the ball nut 141, a first nut pulley 143a which is provided on an outer circumferential surface of the ball nut 141 (e.g. formed directly on it or coupled to it) and has first nut pulley teeth 143-1 which are formed on an outer circumferential surface of the first nut pulley 143a, a second nut pulley 143b which is provided on the outer circumferential surface of the ball nut 141 and has second nut pulley teeth 143-2,which are formed on an outer circumferential surface of the second nut pulley 143b and are configured with a specified angular offset relative to a helix angle B of the first nut pulley teeth 143-1, a first motor pulley 142a provided on a first motor 145 and having first motor pulley teeth 142-1 formed on an outer circumferential surface of the first motor pulley 142a and identical to or corresponding to the first nut pulley teeth 143-1, a second motor pulley 142b provided on a second motor 147 and having second motor pulley teeth 142-2 formed on an outer circumferential surface of the second motor pulley 142b and identical to or corresponding to the second nut pulley teeth 143-2, a first belt 149a coupled to the first nut pulley 143a and the first motor pulley 142a,a second belt 149b coupled to the second mother pulley 143b and the second motor pulley 142b, a first motor sensor 145s configured to detect a rotational position of a shaft 145a of the first motor 145, a second motor sensor 147s configured to detect a rotational position of a shaft 147a of the second motor 147, and an electronic control device or controller 110 configured to receive or use an electrical signal as an input value and to control an output value or signal to be transmitted to the first motor 145 and the second motor 147.

[0041] The steering device according to one embodiment of the present disclosure can include the ball nut 141, which is operationally coupled to the rack 130 by means of the balls 144 and is configured to move or displace the rack 130 in the axial direction by rotating the ball nut 141; the first nut pulley 143a, which is provided on the outer circumferential surface of the ball nut 141 and has the first nut pulley teeth 143-1 formed on the outer circumferential surface of the first nut pulley 143a; the second nut pulley 143b, which is provided on the outer circumferential surface of the ball nut 141 and has the second nut pulley teeth 143-2 formed on the outer circumferential surface of the second nut pulley 143b and configured with a specified angular offset relative to the helix angle B of the first nut pulley teeth 143-1; and the first motor pulley 142a.which is provided on the first motor 145 and has the first motor pulley teeth 142-1, which are formed on the outer circumferential surface of the first motor pulley 142a and are identical to or correspond to the first mother pulley teeth 143-1, and the second motor pulley 142b, which is provided on the second motor 147 and has the second motor pulley teeth 142-2, which are formed on the outer circumferential surface of the second motor pulley 142b and are identical to or correspond to the second mother pulley teeth 143-2.

[0042] With reference to Fig. 1 In a steering device according to the present disclosure, an angle sensor 105 and a torque sensor 107 can be coupled to a side of a steering shaft 103 which is connected to a steering wheel 101 or arranged around the steering shaft 103.

[0043] In an autonomous driving mode, in which an autonomous driving system drives the vehicle, or in a driver assistance mode, in which a driver assistance system, such as an Advanced Driver Assistance System (ADAS), assists a driver in operating the vehicle, the electronic control unit 110 controls a steering shaft motor 120, the first motor 145 and the second motor 147 by transmitting one or more control signals to the steering shaft motor 120, the first motor 145 and the second motor 147 in response to electrical signals transmitted by various sensors that are installed in or on or associated with a vehicle.

[0044] In a driver driving mode, the electronic control unit 110 controls the steering shaft motor 120, the first motor 145 and the second motor 147 by outputting one or more control signals to the steering shaft motor 120, the first motor 145 and the second motor 147 in response to electrical signals transmitted by the angle sensor 105, which detects an actuation or rotation angle of the steering wheel 101 by the driver, electrical signals transmitted by the torque sensor 107, and electrical signals transmitted by various other sensors that are installed in or on the vehicle or associated with it.

[0045] In a Fig. In the illustrated embodiment 1, the angle sensor 105 and the torque sensor 107 are provided as two separate and individual sensors. Alternatively, the angle sensor 105 and the torque sensor 107 can be integrated into a single sensor, such as a torque angle sensor.

[0046] The steering shaft motor 120 may be connected to or associated with a speed reducer configured to reduce the rotational speed of the steering shaft motor 120, including, for example, but not limited to, one or more gears, one or more pulleys and / or one or more belts.

[0047] During normal driving, the steering shaft motor 120 provides the driver with appropriate steering feedback by supplying a reaction force to the steering shaft 103, so that the driver can feel a steering reaction force against the driver's input of the steering wheel 101. The steering shaft motor 120 can also be referred to as a reaction force motor. However, as described below, the steering shaft motor 120 can not only provide the reaction force but also operate according to autonomous steering principles when the steering shaft motor 120 is operating in autonomous driving mode.

[0048] Additionally, the steering shaft motor 120 rotates the steering shaft 103, so that autonomous steering can be carried out under the control of the electronic control unit 110 without the involvement of driving or the intention of the driver when the steering shaft motor 120 is operating in autonomous driving mode.

[0049] Furthermore, in a steer-by-wire steering device, since the steering wheel 101 is not mechanically connected to the rack 130 and a wheel 131, a device for mechanically restricting or limiting a rotation range of the steering wheel 101 may be included to prevent the steering shaft 103 from rotating infinitely when the driver operates the steering wheel 101.

[0050] For example, a rotation angle limiting device 125 may be provided to limit or restrict a rotation range of the steering wheel 101 to prevent the steering shaft 103 from rotating infinitely.

[0051] The first motor 145 and the second motor 147 move the rack 130 or cause the rack 130 to move by means of a rack-and-pinion motion device 140 in order to steer the wheels 131 which are provided or connected to two opposite sides of the rack 130 by means of tie rods 133 and kingpin arms 135 by moving the rack 130.

[0052] The rack and pinion motion device 140 comprises the ball nut 141, the first nut pulley 143a, the second nut pulley 143b, the first motor pulley 142a, and the second motor pulley 142b. The ball nut 141 can be rotatably coupled to the rack 130 by means of the balls 144 and configured to displace the rack 130 in the axial direction of the rack and pinion motion device 140 by rotating the ball nut 141. The first nut pulley 143a can be provided on one side of the outer circumferential surface of the ball nut 141, and the second nut pulley 143b can be provided on the other side of the outer circumferential surface of the ball nut 141. The first motor pulley 142a can be coupled to the first motor 145 (e.g.,The first motor pulley 142b can be coupled to the second motor 147 (e.g., attached to a shaft of the first motor 145) or formed directly on a rotatable part of the first motor 145 and connected to the first nut pulley 143a by the first belt 149a. The second motor pulley 142b can be coupled to the second motor 147 (e.g., attached to a shaft of the second motor 147) or formed directly on a rotatable part of the second motor 147 and connected to the second nut pulley 143b by the second belt 149a.

[0053] Furthermore, the balls 144 are rotatably arranged between a rack screw groove formed on an outer circumferential surface of the rack 130 and a nut screw groove formed on an inner circumferential surface of the ball nut 141, so that the rack 130 can be moved in the axial direction of the rack motion device 140 by the rotation of the ball nut 141.

[0054] In the embodiments of the present disclosure described above, however, the angle sensor 105 and the torque sensor 107 are provided on or around the steering shaft 103, and the steering device according to one embodiment of the present disclosure may include a vehicle speed sensor 102, an ultrasonic sensor 104, and an image sensor 106 for transmitting steering information to the electronic control unit 110. Various types of sensors, such as radar and lidar, may also be added to an embodiment of the present disclosure.

[0055] In a steer-by-wire steering device, since the steering wheel 101 is not mechanically connected to the rack 130 and the wheel 131, a device for mechanically limiting the rack 130 may be included to prevent the rack 130 from rotating due to a torque of the ball nut 141, which is rotated by the rack motion device 140.

[0056] For example, a rotation prevention element 150 is configured to support the axial displacement of the rack 130 and to prevent the rotation of the rack 130.

[0057] In a Fig. In the illustrated embodiment, a single anti-rotation element 150 is provided on one side of the rack 130. Alternatively, a plurality of anti-rotation elements 150 can be provided to support the rack 130. The number of anti-rotation elements 150, the axial position of the anti-rotation element 150, or the like can vary depending on the configuration and required operation of the first and second motors 145 and 147 and the required torque of the ball nut 141 of the rack motion device 140.

[0058] In a Fig. In the illustrated embodiment, the first motor 145 and the second motor 147 are arranged such that they face each other, so that a shaft 145a of the first motor 145 and a shaft 147a of the second motor 147 are aligned coaxially and arranged parallel to a central axis of the rack 130.

[0059] In another in Fig. In the illustrated embodiment 3, the first motor 145 is arranged on one side of the rack 130 and the second motor 147 is arranged on the other side of the rack 130, so that the rack 130 is positioned between the shaft 145a of the first motor 145 and the shaft 147a of the second motor 147, and the shaft 145a of the first motor 145 and the shaft 147a of the second motor 147 are arranged parallel to the central axis of the rack 130 and are located on two opposite sides of the central axis of the rack 130.

[0060] As described above, the exemplary arrangements of the first and second motors 145 and 147 and the rack 130, which are shown in Fig. 1 and Fig. 2 are illustrated, reducing the package size of the steering device, which makes it more compact in volume, and simplifying the process of assembling the steering device, the first motor 145, the first belt 149a, the second motor 147 and the second belt 149b.

[0061] With reference to Fig. 4. The outer diameter mD1 of the first motor pulley 142a and the outer diameter mD2 of the second motor pulley 142b can be different from each other, and the outer diameter nD1 of the first mother pulley 143a and the outer diameter nD2 of the second mother pulley 143b can be the same.

[0062] This means that the first nut pulley 143a and the second nut pulley 143b rotate while maintaining the same phase angle without a phase difference between them when the first motor 145 and the second motor 147 are operating. The first motor pulley 142a and the second motor pulley 142b rotate while a phase difference between them gradually changes when the first motor 145 and the second motor 147 are operating.

[0063] In a Fig. In the illustrated embodiment 4, the first nut pulley 143a and the second nut pulley 143b are provided separately and connected to one section and the other section of the outer circumferential surface of the ball nut 141. However, as shown in Fig. Figure 5 illustrates that the first nut pulley 143a and the second nut pulley 143b are integrated as a single piece with the same outer diameter. This is described below.

[0064] The first motor 145 can have a first motor sensor 145s configured to detect a rotational position of the shaft 145a of the first motor 145, and the second motor 147 can have a second motor sensor 147s configured to detect a rotational position of the shaft 147a of the second motor 147.

[0065] When the first motor 145 is operating, the first motor sensor 145s detects a direction and angle of rotation of the shaft 145a of the first motor 145, and the first motor sensor 145s outputs a signal indicating the direction and angle to the electronic control unit 110.

[0066] When the second motor 147 is operating, the second motor sensor 147s detects the direction and angle of rotation of the shaft 147a of the second motor 147, and the second motor sensor 147s outputs a signal indicating the direction and angle of rotation of the shaft 147a of the second motor 147 to the electronic control unit 110.

[0067] Therefore, the electronic control unit 110 can determine a linear position of the rack 130 based on a first position of the shaft 145a of the first motor 145, which is detected by the first motor sensor 145s, and a second position of the shaft 147a of the second motor 147, which is detected by the second motor sensor 147s, and output a control signal to the first motor 145 and the second motor 147.

[0068] This means that the electronic control unit 110 sets an angle between a reference point on the shaft 145a of the first motor 145 when the first motor 145 is stopped and a reference point on the shaft 147a of the second motor 147 when the second motor 147 is stopped, to a reference position value. The electronic control unit 10 sets an angle between the reference point on the shaft 145a of the first motor 145 and the reference point on the shaft 147a of the second motor 147 after the first and second motors 145 and 147 have been operated, to an operating position value. The electronic control unit 10 determines the linear position of the rack 130 based on the difference between the reference position value and the operating position value.

[0069] For example, the difference between the reference position value and the operating position value can be set from 0° to 360°. A maximum displacement of the rack 130 is set within this range. The electronic control unit 110 determines the displacement position of the rack 130 based on at least one of the following: a rotation ratio between the first motor pulley 142a and the first nut pulley 143a, a rotation ratio between the second motor pulley 142b and the second nut pulley 143b, an outer diameter and an inner diameter of the ball nut 141, an outer diameter of the rack 130, or a helix angle between the rack bolt groove and the nut bolt groove.

[0070] Additionally, the electronic control unit 110 can determine the linear position of the rack 130 by setting the difference between the reference position value and the operating position value to a motion value and comparing the motion value with preset data. For example, the motion value can be set from 0° to 360°, and the maximum displacement of the rack 130 can be set within this range.

[0071] The preset data can be data that includes the displacement amount of the rack 130, which corresponds to the movement value determined on the basis of at least one of the outer diameters of the first and second motor pulleys 142a and 142b, the outer diameters of the first and second nut pulleys 143a and 143b, the outer and inner diameters of the ball nut 141 and / or the outer diameter of the rack 130.

[0072] For example, the first motor pulley 142a and the second motor pulley 142b have different outer diameters, and the first nut pulley 143a and the second nut pulley 143b have the same outer diameter, so that the electronic control unit 110 can determine the displacement position of the rack 130 based on the first position of the shaft 145a of the first motor 145, which is detected by the first motor sensor 145s, and the second position of the shaft 147a of the second motor 147, which is detected by the second motor sensor 147s, and output a signal to control the first motor 145 and the second motor 147.

[0073] With reference to Fig. 4. The first nut pulley 143a and the second nut pulley 143b can be integrated into a single piece with the same outer diameter.

[0074] In an example where the first mother pulley 143a and the second mother pulley 143b are integrated into a single piece with the same outer diameter, the first belt 149a is coupled to one section of the integrated pulley, and the second belt 149b is coupled to the other section of the integrated pulley, so that the first belt 149a and the second belt 149b can each be connected to the first motor pulley 142a and the second motor pulley 142b, respectively.

[0075] Furthermore, the first motor 145 can have the first motor sensor 145s, which is configured to detect the rotational position of the shaft 145a of the first motor 145, and the second motor 147 can have the second motor sensor 147s, which is configured to detect the rotational position of the shaft 147a of the second motor 147.

[0076] When the first motor 145 is operating, the first motor sensor 145s detects the direction and angle of rotation of the shaft 145a of the first motor 145, and the first motor sensor 145s transmits the direction and angle to the electronic control unit 110.

[0077] When the second motor 147 is operating, the second motor sensor 147s detects the direction and angle of rotation of the shaft 147a of the second motor 147, and the second motor sensor 147s transmits a signal indicating the direction and angle to the electronic control unit 110.

[0078] Therefore, the electronic control unit 110 can determine the linear position of the rack 130 based on the first position of the shaft 145a of the first motor 145, which is detected by the first motor sensor 145s, and the second position of the shaft 147a of the second motor 147, which is detected by the second motor sensor 147s, and output a signal to control the first motor 145 and the second motor 147.

[0079] In an exemplary embodiment, which is described in Fig. As illustrated in Figure 6, the outer diameter mD1 of the first motor pulley 142a and the outer diameter mD2 of the second motor pulley 142b can be the same, and the outer diameter nD1 of the first mother pulley 143a and the outer diameter nD2 of the second mother pulley 143b can be different.

[0080] The first nut pulley 143a, the second nut pulley 143b, and the ball nut 141 rotate at the same speed. Therefore, the first nut pulley 143a and the second nut pulley 143b maintain the same phase angle and rotate without a phase difference when the first motor 145 and the second motor 147 are operating. However, the first motor pulley 142a and the second motor pulley 142b rotate with a gradually changing phase difference.

[0081] Furthermore, the first motor 145 can have the first motor sensor 145s, which is configured to detect the rotational position of the shaft 145a of the first motor 145, and the second motor 147 can have the second motor sensor 147s, which is configured to detect the rotational position of the shaft 147a of the second motor 147.

[0082] When the first motor 145 is operating, the first motor sensor 145s detects the direction and angle of rotation of the shaft 145a of the first motor 145, and the first motor sensor 145s outputs a signal indicating the direction and angle of rotation of the shaft 145a of the first motor 145 to the electronic control unit 110.

[0083] Furthermore, when the second motor 147 is operating, the second motor sensor 147s detects the direction and rotation angle of the shaft 147a of the second motor 147, and the second motor sensor 147s transmits the direction and rotation angle of the shaft 147a of the second motor 147 to the electronic control unit 110.

[0084] Therefore, the electronic control unit 110 can output a signal to control the first motor 145 and the second motor 147 by determining the linear position of the rack 130 by the above-mentioned determination process based on the first position of the shaft 145a of the first motor 145, which is detected by the first motor sensor 145s, and the second position of the shaft 147a of the second motor 147, which is detected by the second motor sensor 147s.

[0085] In an exemplary embodiment, which is described in Fig. As shown in Figure 7, the outer diameter mD1 of the first motor pulley 142a and the outer diameter mD2 of the second motor pulley 142b can be different from each other, and the outer diameter nD1 of the first mother pulley 143a and the outer diameter nD2 of the second mother pulley 143b can also be different from each other.

[0086] Even in this case, the first nut pulley 143a, the second nut pulley 143b, and the ball nut 141 rotate at the same speed. Therefore, the first nut pulley 143a and the second nut pulley 143b maintain the same phase angle and rotate without a phase difference when the first motor 145 and the second motor 147 are operating.

[0087] Furthermore, the first motor pulley 142a and the second motor pulley 142b rotate while a phase difference is gradually changed when the first motor 145 and the second motor 147 are operating.

[0088] The first motor 145 can have the first motor sensor 145s, which is configured to detect the rotational position of the shaft 145a of the first motor 145, and the second motor 147 can have the second motor sensor 147s, which is configured to detect the rotational position of the shaft 147a of the second motor 147.

[0089] Therefore, the electronic control unit 110 can output a signal to control the first motor 145 and the second motor 147 by determining the linear position of the rack 130 by the above-mentioned determination process based on the first position of the shaft 145a of the first motor 145, which is detected by the first motor sensor 145s, and the second position of the shaft 147a of the second motor 147, which is detected by the second motor sensor 147s.

[0090] In an exemplary embodiment of Fig. 8. First motor pulley teeth 142-1 are provided on an outer circumferential surface of the first motor pulley 142a, and first nut pulley teeth 143-1 are provided on an outer circumferential surface of the first nut pulley 143a. The first motor pulley teeth 142-1 and the first nut pulley teeth 143-1 can be coupled to first belt teeth 149-1, which are provided on an inner circumferential surface of the first belt 149a.

[0091] Since the first engine pulley teeth 142-1 and the first mother pulley teeth 143-1 are coupled with the first belt teeth 149-1 to transmit power, the first engine pulley teeth 142-1 and the first mother pulley teeth 143-1 are the same size as the first belt teeth 149-1.

[0092] Second motor pulley teeth 142-2 are provided on an outer circumferential surface of the second motor pulley 142b, and second nut pulley teeth 143-2 are provided on an outer circumferential surface of the second nut pulley 143b. The second motor pulley teeth 142-2 and the second nut pulley teeth 143-2 can be coupled to second belt teeth 149-2, which are provided on an inner circumferential surface of the second belt 149b.

[0093] Since the second motor pulley teeth 142-2 and the second nut pulley teeth 143-2 are coupled with the second belt teeth 149-2 to transmit power, the second motor pulley teeth 142-2 and the second nut pulley teeth 143-2 can be the same size as the second belt teeth 149-2.

[0094] Furthermore, the number of teeth on the first motor pulley 142-1 and the number of teeth on the second motor pulley 142-2 can be different, and the number of teeth on the first nut pulley 143-1 and the number of teeth on the second nut pulley 143-2 can be the same.

[0095] The first motor pulley teeth 142-1 and the second motor pulley teeth 142-2 have the same circumferential pitch, different pitch circle diameters, and a different number of teeth. The first nut pulley teeth 143-1 and the second nut pulley teeth 143-2 have the same circumferential pitch, the same pitch circle diameter, and a different number of teeth.

[0096] The first motor 145 can have the first motor sensor 145s, which is configured to detect the rotational position of the shaft 145a of the first motor 145, and the second motor 147 can have the second motor sensor 147s, which is configured to detect the rotational position of the shaft 147a of the second motor 147.

[0097] Therefore, the electronic control unit 110 can determine the linear position of the rack 130 based on the first position of the shaft 145a of the first motor 145, which is detected by the first motor sensor 145s, and the second position of the shaft 147a of the second motor 147, which is detected by the second motor sensor 147s, and output a signal to control the first motor 145 and the second motor 147.

[0098] This means that, as in the determination method mentioned above, the difference between the reference position value and the operating position value can be set from 0° to 360°, and the maximum displacement of the rack 130 is set within this range. The electronic control unit 110 determines the displacement position of the rack 130 based on at least one of the following: a pitch circle diameter ratio or a tooth number ratio between the first motor pulley 142a and the first nut pulley 143a, a pitch circle diameter ratio or a tooth number ratio between the second motor pulley 142b and the second nut pulley 143b, the outer and inner diameters of the ball nut 141, or the outer diameter of the rack 130.

[0099] Additionally, similar to the determination method mentioned above, the electronic control unit 110 can determine the displacement position of the rack 130 by setting the difference between the reference position value and the operating position value to the movement value and comparing the movement value with preset data. In this case, the movement value can be set from 0° to 360°, and the maximum displacement of the rack 130 is set within this range.

[0100] In this case, the preset data can be data that includes the displacement amount of the rack 130, which corresponds to the movement value determined on the basis of at least one of the pitch circle diameters and the number of teeth of the first and second motor pulleys 142a and 142b, the pitch circle diameters and the number of teeth of the first and second nut pulleys 143a and 143b, the outer and inner diameters of the ball nut 141 and / or the outer diameter of the rack 130.

[0101] As described above, the number of teeth on the first motor pulley 142-1 and the number of teeth on the second motor pulley 142-2 are different, while the number of teeth on the first nut pulley 143-1 and the number of teeth on the second nut pulley 143-2 are the same. The electronic control unit 110 can output a signal to control the first motor 145 and the second motor 147 by determining the displacement position of the rack 130 based on the first position of the shaft 145a of the first motor 145, detected by the first motor sensor 145s, and the second position of the shaft 147a of the second motor 147, detected by the second motor sensor 147s.

[0102] Additionally, the number of teeth on the first motor pulley 142-1 and the number of teeth on the second motor pulley 142-2 can be the same, and the number of teeth on the first nut pulley 143-1 and the number of teeth on the second nut pulley 143-2 can be different.

[0103] The first motor pulley teeth 142-1 and the second motor pulley teeth 142-2 have the same circumferential pitch, the same pitch circle diameter, and the same number of teeth. The first nut pulley teeth 143-1 and the second nut pulley teeth 143-2 have the same circumferential pitch but different pitch circle diameters and different numbers of teeth.

[0104] Furthermore, the first motor 145 can have the first motor sensor 145s, which is configured to detect the rotational position of the shaft 145a of the first motor 145, and the second motor 147 can have the second motor sensor 147s, which is configured to detect the rotational position of the shaft 147a of the second motor 147.

[0105] Therefore, the electronic control unit 110 can output a signal to control the first motor 145 and the second motor 147 by determining the displacement position of the rack 130 by the above-mentioned determination process based on the first position of the shaft 145a of the first motor 145, which is detected by the first motor sensor 145s, and the second position of the shaft 147a of the second motor 147, which is detected by the second motor sensor 147s.

[0106] Additionally, the number of teeth on the first motor pulley 142-1 and the number of teeth on the second motor pulley 142-2 may be different, and the number of teeth on the first nut pulley 143-1 and the number of teeth on the second nut pulley 143-2 may be different.

[0107] This means that the first motor pulley teeth 142-1 and the second motor pulley teeth 142-2 can have the same circumferential pitch but different pitch circle diameters and a different number of teeth. Similarly, the first nut pulley teeth 143-1 and the second nut pulley teeth 143-2 have the same circumferential pitch but different pitch circle diameters and a different number of teeth.

[0108] Furthermore, the first motor 145 can have the first motor sensor 145s, which is configured to detect the rotational position of the shaft 145a of the first motor 145, and the second motor 147 can have the second motor sensor 147s, which is configured to detect the rotational position of the shaft 147a of the second motor 147.

[0109] Therefore, the electronic control unit 110 can output a signal to control the first motor 145 and the second motor 147 by determining the displacement position of the rack 130 by the above-mentioned determination process based on the first position of the shaft 145a of the first motor 145, which is detected by the first motor sensor 145s, and the second position of the shaft 147a of the second motor 147, which is detected by the second motor sensor 147s.

[0110] In an exemplary embodiment of Fig. 9 To prepare for a case in which one of the first motor sensor 145s and the second motor sensor 147s is not functional, a rotary gear 139, rotatably engaged with a rack thread 130b provided on the rack 130, can be rotatably coupled to the rack 130, and a rotary angle sensor 137s can be configured to detect a rotary angle of the rotary gear 139.

[0111] The rotary gear 139 can be configured to rotate while supported on a rack housing by means of a bearing. The rotation angle sensor 137s can be installed on or around a shaft 137 of the rotary gear 139 and configured to detect a rotation angle of the rotary gear 139 and transmit the rotation angle of the rotary gear 139 to the electronic control unit 110.

[0112] Therefore, even if one of the first motor sensor 145s and the second motor sensor 147s is not functional, the electronic control unit 110 can output a signal to control the first motor 145 and the second motor 147 by determining the displacement position of the rack 130 based on the pre-stored transmission ratio between the rack thread 130b and the rotary gear 139 and the rotation angle of the rotary gear 139 received from the rotation angle sensor 137s.

[0113] Furthermore, various embodiments of a rotation prevention element or means in the steering device mentioned above can be provided below.

[0114] Some embodiments of the anti-rotation element 150 are described in more detail below with reference to Fig. 9, Fig. 10, Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15, Fig. 16, Fig. 17 to Fig. 18 described.

[0115] As in Fig. As illustrated in Figure 10, the anti-rotation element 150 can be coupled to one radial side and the other radial side of the rack 130 and support two opposite sides of the rack 130, thus preventing the rack 130 from rotating.

[0116] The anti-rotation element 150 can include a shaft 230 configured to support a support surface 130-1 formed on the outer circumferential surface of the rack 130, and a support yoke 240 configured to support the outer circumferential surface of the rack 130 opposite or corresponding to a position where the shaft 230 is supported.

[0117] The support surface 130-1, which is formed on the outer circumferential surface of the rack 130, can be formed by machining or grinding the outer circumferential surface of the rack 130.

[0118] The support surface 130-1 can be recessed from the outer circumferential surface of the rack 130 and can be designed as a curved surface, a flat surface or a combination thereof.

[0119] The support surface 130-1 extends in an axial direction of the rack 130 in order to be supported by the shaft 230 when the rack 130 moves in the axial direction of the rack 130.

[0120] Optionally, a coating layer can be provided on the support surface 130-1 and made of a low-friction material with a low coefficient of friction, such as fluorinated resin or ceramic, to minimize or reduce friction with the shaft 230.

[0121] The shaft 230, which supports the support surface 130-1 of the rack 130, can include an upper end support section 231, a body section 233 and a lower end support section 235.

[0122] When the rack 130 moves, the shaft 230 is held in place by a rack housing (e.g. 160 made of Fig. 10) supported and is configured to be rotatable, so that the body section 233 supports the support surface 130-1 of the rack 130, thereby preventing the rack 130 from rotating.

[0123] A needle bearing 236 can be coupled to the body section 233 to minimize or reduce friction with the support surface 130-1 of the rack 130.

[0124] The upper end support section 231, which has a larger diameter than the body section 233, can be provided above the body section 233, and an upper end bearing 234 can be coupled to the upper end support section 231 to be rotatably supported on the rack housing.

[0125] An upper plug 232 can be coupled to a top surface of the upper end support section 231 to prevent foreign substances from being introduced into the rack housing.

[0126] The lower end support section 235, which has a smaller diameter than the body section 233, can be provided below the body section 233, and a lower end bearing 238 can be coupled to the lower end support section 235 to be rotatably supported on the rack housing.

[0127] The support yoke 240, which supports the outer circumferential surface of the rack 130 opposite a position where the shaft 230 is supported, supports the rack 130 in the direction of the shaft 230 when the rack 130 moves, thus preventing the rack 130 from rotating.

[0128] A support section 241 with a curved surface can be formed at an end section of the support yoke 240 and can be supported on the outer circumferential surface of the rack 130, making close contact with it. The support section 241 with a curved surface can have a curved surface that is identical to the outer circumferential surface of the rack 130.

[0129] The support yoke 240 can have a predetermined stiffness and elasticity and can be made from one or more materials selected from a group consisting of polyacetal (POM), polyamide (PA), polycarbonate (PC), polyimide (PI), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) and phenolformaldehyde (PF).

[0130] An elastic ring 245 can be coupled to an outer circumferential surface of the support yoke 240 to prevent rattling noises with the rack housing.

[0131] One or more elastic rings 245 can be coupled to the outer circumferential surface of the support yoke 240.

[0132] The elastic ring 245 can be made of a material capable of absorbing vibrations and noise and exhibiting predetermined elasticity and stiffness. For example, the elastic ring 245 can be made of one or more materials selected from a group consisting of natural rubber (NR), nitrile butadiene rubber (NBR), chloroprene rubber (CR), ethylene propylene terpolymer (EPDM), fluororubber (FPM), styrene butadiene rubber (SBR), chlorosulfonated polyethylene (CSM), urethane, and silicone, all of which possess the aforementioned properties.

[0133] A yoke plug 243 can be coupled to an end section of the support yoke 240, press-fitted or screwed to the rack housing and fix the support yoke 240.

[0134] Furthermore, an elastic body can be coupled between the support yoke 240 and the yoke plug 243 and elastically support the support yoke 240 in the direction of the rack 130.

[0135] As in Fig. As illustrated in Figure 11, the anti-rotation element 150 can be coupled to one radial side and the other radial side of the rack 130 and support two opposite sides of the rack 130, thereby preventing the rack 130 from rotating.

[0136] The anti-rotation element 150 can include a needle bearing 220 configured to support the support surface 130-1 formed on the outer circumferential surface of the rack 130, a support yoke 225 rotatably coupled to the needle bearing 220, and a rack bushing 229 configured to support the outer circumferential surface of the rack 130 opposite a position where the needle bearing 220 is supported.

[0137] The support surface 130-1 can be formed on the outer circumferential surface of the rack 130. For example, the support surface 130-1 can be formed by machining or grinding the outer circumferential surface of the rack 130.

[0138] The support surface 130-1 can be recessed into the outer circumferential surface of the rack 130. The support surface 130-1 can be designed as a curved surface or a flat surface.

[0139] The support surface 130-1 extends longitudinally in the axial direction of the rack 130. And the support surface 130-1 can be supported by the needle bearing 220 when the rack 130 moves in the axial direction of the rack 130.

[0140] A coating layer can be provided on the support surface 130-1 and made of a low-friction material, such as fluorinated resin or ceramic, to minimize or reduce friction with the needle bearing 220.

[0141] The needle bearing 220 can be configured to support the support surface 130-1 of the rack 130, the needle bearing 220 can have a support shaft 221 provided on a central section of the needle bearing 220, and the support shaft 221 is attached to the support yoke 225 so that the needle bearing 220 can be rotatably supported by the support yoke 225.

[0142] An outer ring 222 of the needle bearing 220 is supported on the support surface 130-1 and is configured to rotate when the rack 130 moves, in order to prevent the rack 130 from rotating.

[0143] The outer ring 222 of the needle bearing 220 can be arranged in a position that projects from an end section of the support yoke 225, so that the outer ring 222 can be supported on the support surface 130-1.

[0144] The support yoke 225 supports the needle bearing 220 in the direction of the support surface 130-1 when the rack 130 moves, in order to prevent the rack 130 from rotating.

[0145] The support yoke 225 can have a predetermined stiffness and elasticity and can be made from one or more materials selected from a group consisting of polyacetal (POM), polyamide (PA), polycarbonate (PC), polyimide (PI), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) and phenolformaldehyde (PF).

[0146] An elastic ring 226 can be coupled to the outer circumferential surface of the support yoke 225 to prevent rattling noises with the rack housing 160.

[0147] One or more elastic rings 226 can be coupled to the outer circumferential surface of the support yoke 225.

[0148] The elastic ring 226 can be made of a material capable of absorbing vibrations and noise and exhibiting predetermined elasticity and stiffness. Therefore, the elastic ring 226 can be made of one or more materials selected from a group consisting of natural rubber (NR), nitrile butadiene rubber (NBR), chloroprene rubber (CR), ethylene propylene terpolymer (EPDM), fluororubber (FPM), styrene butadiene rubber (SBR), chlorosulfonated polyethylene (CSM), urethane, and silicone, all of which possess the aforementioned properties.

[0149] A yoke plug 227 can be coupled to one end of the support yoke 225, press-fitted or screwed to the rack housing 160, and configured to fix the position of the support yoke 225.

[0150] Furthermore, an elastic body 228 can be coupled between the support yoke 225 and the yoke plug 227 and elastically support the support yoke 225 by exerting an elastic force in the direction of the rack 130.

[0151] The rack bushing 229, which supports the outer circumferential surface of the rack 130 against another outer circumferential surface of the rack 130, which supports the needle bearing 220, can be formed in a semi-cylindrical shape, which is produced by cutting a part of an outer circumferential surface thereof.

[0152] The rack bushing 229 supports the rack 130 in the direction of the needle bearing 220 in the radial direction of the rack bushing 229 when the rack 130 moves, thus preventing the rack 130 from rotating.

[0153] The rack bushing 229 can have a curved surface that is identical to or corresponds to the outer circumferential surface of the rack 130, so that it is in close contact with and supported on the outer circumferential surface of the rack 130.

[0154] A bushing coupling groove 166-1, with which the rack bushing 229 is coupled, can be formed on an inner circumferential surface of the rack housing 160.

[0155] The rack bushing 229 can have a fastening projection 229a formed on or around an end section of an outer circumferential surface of the rack bushing 229 to prevent the axial position of the rack bushing 229 from being separated or rotated when the rack 130 moves.

[0156] A fastening groove 166-2 can be formed on the inner circumferential surface of the rack housing 160, and the fastening projection 229a of the rack bushing 229 can be coupled to the fastening groove 166-2 of the rack housing 160.

[0157] The rack bushing 229 can have a predetermined stiffness and elasticity and can be made from one or more materials selected from a group consisting of polyacetal (POM), polyamide (PA), polycarbonate (PC), polyimide (PI), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) and phenolformaldehyde (PF).

[0158] In a Fig. In the illustrated embodiment 12, the anti-rotation element 150 can be configured to prevent the rack 130 from rotating about its central axis. The anti-rotation element 150 supports the outer circumferential surface of the rack 130 and can also be supported on the inner circumferential surface of the rack housing 160.

[0159] The anti-rotation element 150 can include a support element 210, one end section of which is arranged or supported in a rack support groove 132 formed on the outer circumferential surface of the rack 130, and the other end section of which is arranged or supported in a housing groove 162 formed on the inner circumferential surface of the rack housing 160, and an elastic element 212 coupled to the support element 210 and configured to elastically support the inner circumferential surface of the rack housing 160.

[0160] The rack support groove 132, which is formed on the outer circumferential surface of the rack 130, can be formed by machining or grinding the outer circumferential surface of the rack 130.

[0161] The rack support groove 132 can be recessed into the outer circumferential surface of the rack 130. The rack support groove 132 can have a curved surface or a flat surface.

[0162] The rack support groove 132 can extend longitudinally in the axial direction of the rack 130 and be supported by the support element 210 when the rack 130 moves in the axial direction of the rack 130.

[0163] A coating layer can be provided on the rack support groove 132 and made of a low-friction material, such as fluoropolymer or ceramic, to reduce or minimize friction with the support element 210.

[0164] The housing groove 162, in which the other end section of the support element 210 is supported, can be formed in a position that faces the rack support groove 132 in the radial direction of the rack 130.

[0165] For example, the housing groove 162 can be formed by machining or grinding the inner circumferential surface of the rack housing 160.

[0166] The housing groove 162 can be recessed into the inner circumferential surface of the rack housing 160 and have a curved surface or a flat surface, so that the support element 210 can prevent the rotation of the rack 130 when the rack 130 moves in the axial direction of the rack 130.

[0167] One end section and the other end section of the support element 210 are coupled to the rack support groove 132 and the housing groove 162 respectively, and a coupling groove 211, with which the elastic element 212 is coupled, is formed on the other end section of the support element 210.

[0168] The support element 210 can have a predetermined stiffness and elasticity and can be made of one or more materials selected from a group consisting of polyacetal (POM), polyamide (PA), polycarbonate (PC), polyimide (PI), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) and phenolformaldehyde (PF).

[0169] The elastic element 212 is coupled to the coupling groove 211 of the support element 210, supports the support element 210, and is configured to exert an elastic force in the direction of the rack 130 while being elastically supported on the inner circumferential surface of the rack housing 160. This ensures that the support element 210 maintains a predetermined distance to avoid colliding with the inner circumferential surface of the rack housing 160 when the rack 130 moves axially. Therefore, rattling noises between the support element 210 and the rack housing 160 are prevented.

[0170] For example, the elastic element 212 can be designed as a curved thin plate.

[0171] A plug bolt 215 can be arranged at an axial end of the support element 210, can be configured to prevent separation of the support element 210, and can be coupled to the inner circumferential surface of the rack housing 160. For example, the plug bolt 215 can be press-fitted and coupled to the inner circumferential surface of the rack housing 160.

[0172] The plug bolt 215 includes a support section 215a, which is configured to support the support element 210 in the axial direction of the rack 130, and a fixing section 215b, which extends from the support section 215a and is fixed to the inner circumferential surface of the rack housing 160.

[0173] The outer circumferential surface of the fixing section 215b has a threaded section which is screwed to the inner circumferential surface of the rack housing 160.

[0174] Furthermore, a fixing element 217 can be coupled to an axial end of the plug bolt 215 to prevent the plug bolt 215 from being loosened and separated.

[0175] A fixing projection 217a, which projects in the radial direction of the rack housing 160, can project from an outer circumferential surface of the fixing element 217.

[0176] A fixing groove 164 can be formed on the inner circumferential surface of the rack housing 160, and the fixing projection 217a of the fixing element 217 can be inserted into the fixing groove 164 and supported by it.

[0177] In one embodiment of Fig. 13 The anti-rotation element 150 can be supported on the outer circumferential surface of the rack 130 and the inner circumferential surface of the rack housing and prevent the rack 130 from rotating about the central axis.

[0178] The anti-rotation element 150 can include a support bushing 205 configured to support the support surface 130-1 formed on the outer circumferential surface of the rack 130, a bushing holder 200 coupled to the outer circumferential surface of the rack 130 and having an inner circumferential surface on which the support bushing 205 is supported, and an elastic element 207 coupled between the bushing holder 200 and the support bushing 205 and configured to elastically support the support bushing 205 by exerting an elastic force in the direction of the rack 130.

[0179] For example, the support surface 130-1, which is formed on the outer circumferential surface of the rack 130, can be formed by machining or grinding the outer circumferential surface of the rack 130.

[0180] The support surface 130-1 can be recessed from the outer circumferential surface of the rack 130 and can have a curved surface or a flat surface.

[0181] The support surface 130-1 extends longitudinally in the axial direction of the rack 130 and is supported by the support bushing 205 when the rack 130 moves in the axial direction.

[0182] A coating layer can be provided on the support surface 130-1 and made of a low-friction material, such as fluoropolymer or ceramic, to minimize or reduce friction with the support bushing 205.

[0183] The housing groove 162, with which the bushing holder 200 is coupled and in which it is supported, is formed on the inner circumferential surface of the rack housing 160 and is positioned so that it faces the support surface 130-1 in the radial direction of the rack 130.

[0184] For example, the housing groove 162 can be formed by machining or grinding the inner circumferential surface of the rack housing 160.

[0185] The housing groove 162 can be recessed from the inner circumferential surface of the rack housing 160 and can have a curved surface or a flat surface.

[0186] Additionally, a stepped projection section 163 with a larger diameter can be formed at an end section of the housing groove 162 on the inner circumferential surface of the rack housing 160, and an end section of the stepped projection section 163 can have an opening in the axial direction of the rack 130.

[0187] The bushing holder 200 has a cylindrical shape. For example, the bushing holder 200 can have a cut-out section, which is produced by cutting a radial side of the bushing holder 200, and a projecting inner circumferential surface 201 that projects radially inwards.

[0188] Furthermore, a bushing coupling groove 203, with which the support bushing 205 is coupled, can be formed on the projecting inner circumferential surface 201. A flange section 206, which projects radially, is supported by or on the stepped projection section 163 of the rack housing 160 and can be formed at an axial end of the bushing holder 200.

[0189] The flange section 206 is supported by or on the stepped projection section 163 to prevent the bushing holder 200 from separating when the rack 130 moves in the axial direction.

[0190] The support bushing 205, which is coupled to the bushing coupling groove 203 of the bushing holder 200, includes a projecting support section 205a that projects from a central section of the support bushing 205, and the elastic element 207 is coupled to the projecting support section 205a.

[0191] For example, the elastic element 207 can be formed in a ring shape and in a conical shape, in which an inner circumferential surface and an outer circumferential surface of the elastic element 207 are stepped in the axial direction, so that the protruding support section 205a can be coupled to an inner circumferential surface of the elastic element 207.

[0192] The elastic element 207 elastically supports the support bushing 205 to exert an elastic force in the direction of the rack 130, and the elastic element 207 can be positioned between the bushing holder 200 and the support bushing 205, forming a gap or space 202 so that the support bushing 205 cannot collide with the bushing holder 200 when the rack 130 moves in the axial direction, in order to prevent or reduce rattling noises between the support bushing 205 and the bushing holder 200.

[0193] The bushing holder 200 and the support bushing 205 can have a predetermined stiffness and elasticity and can be made of one or more materials selected from a group consisting of polyacetal (POM), polyamide (PA), polycarbonate (PC), polyimide (PI), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) and phenolformaldehyde (PF).

[0194] In one embodiment of Fig. 14 The anti-rotation element 150 can support the outer circumferential surface of the rack 130 to prevent the rack 130 from rotating about the central axis of the anti-rotation element 150, and can be supported by the inner circumferential surface of the rack housing 160.

[0195] The anti-rotation element 150 can include a rack bushing 250, comprising an inner circumferential support section 251, which is inserted into and supported by the rack support groove 132 formed on the outer circumferential surface of the rack 130, and an outer circumferential support section 253, which is inserted into and supported by the housing groove 162 formed on the inner circumferential surface of the rack housing 160, and an elastic element 252, which is coupled to the outer circumferential surface of the rack bushing 250 and is configured to elastically support the rack bushing 250.

[0196] For example, the rack support groove 132, which is formed on the outer circumferential surface of the rack 130, can be formed by machining or grinding the outer circumferential surface of the rack 130.

[0197] The rack support groove 132 can be recessed from the outer circumferential surface of the rack 130 and can have a curved surface or a flat surface.

[0198] The rack support groove 132 extends longitudinally in the axial direction of the rack 130 in order to be supported by the rack bushing 250 when the rack 130 moves in the axial direction.

[0199] A coating layer can be provided on the rack support groove 132 and made of a low-friction material, such as fluoropolymer or ceramic, to minimize or reduce friction with the rack bushing 250.

[0200] The inner circumferential support section 251 projects radially inwards from the inner circumferential surface of the rack bushing 250 at a position facing the rack support groove 132.

[0201] The outer circumferential support section 253 projects radially outwards from the outer circumferential surface of the rack bushing 250 and is coupled to the housing groove 162.

[0202] For example, the housing groove 162 can be formed by machining or grinding the inner circumferential surface of the rack housing 160.

[0203] The housing groove 162 can be recessed from the inner circumferential surface of the rack housing 160 and can have a curved surface or a flat surface.

[0204] Two or more outer circumferential support sections 253 can be formed on the outer circumferential surface of the rack bushing 250 and be spaced apart from each other in a circumferential direction.

[0205] For example, a pair of outer circumferential support sections 253 can be formed on the outer circumferential surface of the rack bushing 250 in the circumferential direction at a position corresponding to the inner circumferential support section 251.

[0206] The rack bushing 250 can have a predetermined stiffness and elasticity and can be made from one or more materials selected from a group consisting of polyacetal (POM), polyamide (PA), polycarbonate (PC), polyimide (PI), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) and phenolformaldehyde (PF).

[0207] The elastic element 252 can be coupled to the outer circumferential surface of the rack bushing 250 and can have a ring shape.

[0208] The elastic element 252 can be made of a material capable of absorbing vibrations and noise and exhibiting predetermined elasticity and stiffness. Therefore, the elastic element 252 can be made of one or more materials selected from a group consisting of natural rubber (NR), nitrile butadiene rubber (NBR), chloroprene rubber (CR), ethylene propylene terpolymer (EPDM), fluororubber (FPM), styrene butadiene rubber (SBR), chlorosulfonated polyethylene (CSM), urethane, and silicone, all of which possess the aforementioned properties.

[0209] A coupling groove 252-1, with which the elastic element 252 is coupled, can be formed on the outer circumferential surface of the rack bushing 250.

[0210] The rack bushing 250 can have a cut-out section 254 that is cut in the axial direction, so that the rack bushing 250 is deformable in the radial direction.

[0211] Two or more cut-out sections 254, spaced apart from each other in the circumferential direction, may be provided.

[0212] The cut-out sections 254 can be designed such that one end or the other end of the rack bushing 250 is open at a position where the cut-out section 254 is formed.

[0213] The cut-out sections 254, which are open at one end of the rack bushing 250, and the cut-out section 254, which is open at the other end of the rack bushing 250, can be spaced apart from each other in the circumferential direction and formed in an offset manner.

[0214] Therefore, the rack bushing 250 is elastically supported in the radial direction by an elastic force of the elastic element 252, so that the rack bushing 250 cannot collide with the rack housing 160 when the rack 130 moves in the axial direction, in order to prevent or reduce rattling noises between the rack bushing 250 and the rack housing 160.

[0215] In a Fig. In the illustrated embodiment 15, the anti-rotation element 150 can support the outer circumferential surface of the rack 130 to prevent the rack 130 from rotating about the central axis of the rack 130, and can be supported by the inner circumferential surface of the rack housing 160.

[0216] The anti-rotation element 150 can include a rotary element 191 configured to support the support surface 130-1 formed on the outer circumferential surface of the rack 130, and a support bushing 190 coupled to the housing groove 162 formed on the inner circumferential surface of the rack housing 160, and configured such that the rotary element 191 is rotatably coupled to the support bushing 190.

[0217] For example, the support surface 130-1, which is formed on the outer circumferential surface of the rack 130, can be formed by machining or grinding the outer circumferential surface of the rack 130.

[0218] The support surface 130-1 can be recessed from the outer circumferential surface of the rack 130 and can have a curved surface or a flat surface.

[0219] The support surface 130-1 extends longitudinally in the axial direction of the rack 130 in order to be supported by the rotary element 191 when the rack 130 moves in the axial direction.

[0220] Two or more support surfaces 130-1 can be formed on the outer circumferential surface of the rack 130 and be spaced apart from each other in the circumferential direction of the rack 130.

[0221] For example, a pair of support surfaces 130-1 can be formed on opposite sides of the rack 130 with respect to the center of the rack 130.

[0222] The rotating elements 191 can be configured as a roller or ball that is movably arranged in an inner surface of the support bushing 190 (e.g. within one or more elongated holes of the support bushing 190) and is configured to be rotatable or rollable while supported on the support surface 130-1 of the rack 130.

[0223] The rotating elements 191 can be rotatably supported on both the inner and outer surfaces of the support bushing 190.

[0224] A coating layer can be provided on the support surface 130-1 and made of a low-friction material, such as fluoropolymer or ceramic, to reduce or minimize friction with the rotating element 191.

[0225] The housing groove 162, in which the support bushing 190 is arranged, is formed on the inner circumferential surface of the rack housing 160 at a position that faces a support surface 130-1 of the rotating element 191 in the radial direction.

[0226] The support bushing 190 is coupled to the housing groove 162 of the rack housing 160, and the rotary element 191 is rotatably coupled to the support bushing 190.

[0227] The support bushing 190 can have a predetermined stiffness and elasticity and can be made from one or more materials selected from a group consisting of polyacetal (POM), polyamide (PA), polycarbonate (PC), polyimide (PI), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) and phenolformaldehyde (PF).

[0228] For example, the housing groove 162 can be formed by machining or grinding the inner circumferential surface of the rack housing 160.

[0229] The housing groove 162 can be recessed from the inner circumferential surface of the rack housing 160 and can have a curved surface or a flat surface.

[0230] In a Fig. In the illustrated embodiment 16, the anti-rotation element 150 can support the outer circumferential surface of the rack 130 to prevent the rack 130 from rotating about the central axis and is supported by the inner circumferential surface of the rack housing.

[0231] The anti-rotation element 150 can include a rack bushing 180, which includes one or more rotation support sections 183 rotatably arranged between the rack support groove 132 formed on the outer circumferential surface of the rack 130 and the housing groove 162 formed on the inner circumferential surface of the rack housing 160, an elastic support section 185 arranged between the rack support groove 132 formed on the outer circumferential surface of the rack 130 and the housing groove 162 formed on the inner circumferential surface of the rack housing 160 and elastically supported by it, and a connecting section 181 connecting the rotation support section 183 and the elastic support section 185.

[0232] The rack support groove 132 can be formed on the outer circumferential surface of the rack 130. For example, the rack support groove 132 can be formed by machining or grinding the outer circumferential surface of the rack 130.

[0233] The rack support groove 132 can be recessed from the outer circumferential surface of the rack 130 and can have a curved surface or a flat surface.

[0234] The rack support groove 132 extends longitudinally in the axial direction of the rack 130 and is supported by the rotary support section 183 and the elastic support section 185 when the rack 130 moves axially. The rotary support section 183 and the elastic support section 185 can be arranged in the rack support groove 132.

[0235] The housing groove 162 is formed on the inner circumferential surface of the rack housing 160 at the position that faces or corresponds to the rack support groove 132 in the radial direction.

[0236] For example, the housing groove 162 can be formed by machining or grinding the inner circumferential surface of the rack housing 160.

[0237] The housing groove 162 can be recessed from the inner circumferential surface of the rack housing 160 and can have a curved surface or a flat surface.

[0238] A coating layer can be provided on the rack support groove 132 and the housing groove 162 and can be made of a low-friction material, such as fluoropolymer or ceramic, to minimize or reduce friction with the rack bushing 180.

[0239] The rack bushing 180 can have two or more rotary support sections 183 and / or two or more elastic support sections 185.

[0240] Balls can be coupled to the rotary support sections 183, and the balls can be spaced apart from each other in the axial direction.

[0241] The elastic support section 185 can have a substantially cylindrical shape. The elastic support section 185 can have an opening on one side.

[0242] The rack bushing 180 is elastically supported by the rack support groove 132 and the housing groove 162 by an elastic deformation force of the elastic support section 185, thereby maintaining a predetermined interval so that the rack bushing 180 does not collide with the rack housing 160 when the rack 130 moves in the axial direction, in order to prevent rattling noises between the rack bushing 180 and the rack housing 160.

[0243] In a Fig. In the illustrated embodiment 17, the anti-rotation element 150 can support the outer circumferential surface of the rack 130 to prevent the rack 130 from rotating about the central axis, and the anti-rotation element 150 can be supported by the inner circumferential surface of the rack housing 160.

[0244] The anti-rotation element 150 can include a rack bushing 170 having a first support section 171 and a second support section 175. The first support section 171 can be configured to support the support surface 130-1 formed on the outer circumferential surface of the rack 130. The second support section 175 can extend from or be connected to the first support section 171, can be configured to support the outer circumferential surface of the rack 130, and can have an outer circumferential surface on which a locking projection 173, coupled to the housing groove 162, is formed on the inner circumferential surface of the rack housing 160.

[0245] For example, the support surface 130-1, which is formed on a part of the outer circumferential surface of the rack 130, can be formed by machining or grinding the outer circumferential surface of the rack 130.

[0246] The support surface 130-1 can be recessed from the outer circumferential surface of the rack 130 and can have a curved surface or a flat surface.

[0247] The support surface 130-1 extends longitudinally in the axial direction of the rack 130 in order to be supported by the first support section 171 when the rack 130 moves in the axial direction.

[0248] An inner circumferential surface 171a of the first support section 171 can be in close contact with and supported by the support surface 130-1 of the rack 130, and an outer circumferential surface of the first support section 171 can be spaced away from the inner circumferential surface of the rack housing 160.

[0249] A coating layer can be provided on the support surface 130-1 and the outer circumferential surface of the rack 130 and can be made of a low-friction material, such as fluoropolymer or ceramic, to minimize or reduce friction with the rack bushing 170.

[0250] The second support section 175 extends from the first support section 171 in the circumferential direction or is connected to it and surrounds the outer circumferential surface of the rack 130.

[0251] The fixing projection 173 extends radially from the outer circumferential surface of the second support section 175.

[0252] The housing groove 162 can be formed on the inner circumferential surface of the rack housing 160, and the fixing projection 173 of the second support section 175 can be inserted into or coupled to the housing groove 162, thereby preventing the rack bushing 170 from rotating.

[0253] For example, the housing groove 162 can be formed by machining or grinding the inner circumferential surface of the rack housing 160.

[0254] The housing groove 162 can be recessed from the inner circumferential surface of the rack housing 160 and can have a curved surface or a flat surface.

[0255] The rack bushing 170 can have a predetermined stiffness and elasticity and can be made from one or more materials selected from a group consisting of polyacetal (POM), polyamide (PA), polycarbonate (PC), polyimide (PI), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) and phenolformaldehyde (PF).

[0256] In a Fig. In the illustrated embodiment 18, the anti-rotation element 150 can be supported by a guide cover 155 which is coupled to the rack housing 160, and can support the outer circumferential surface of the rack 130 to prevent the rack 130 from rotating about the central axis.

[0257] The anti-rotation element 150 can include a support element 151 coupled to the outer circumferential surface of the rack 130, wherein the guide cover 155 is coupled to the rack housing 160 and has an inner circumferential surface that supports the support element 151, and a fastening element 159 configured to fasten the guide cover 155 to the rack housing 160.

[0258] The support element 151 can be coupled to the outer circumferential surface of the rack 130. For example, the support element 151 can be coupled to a coupling groove 134 formed on the outer circumferential surface of the rack 130 by press fitting, bonding, or the like. The coupling groove 134 can be formed by machining or grinding the outer circumferential surface of the rack 130.

[0259] The coupling groove 134 can be recessed into the outer circumferential surface of the rack 130 and can have a curved surface or a flat surface.

[0260] The rack housing 160 can have an opening at a position facing or corresponding to the support element 151, and the guide cover 155 is coupled to and covers the opening of the rack housing 160.

[0261] The inner circumferential surface of the guide cover 155 can have a support groove 155-1 into which and through which the support element 151 is inserted and supported.

[0262] The support groove 155-1 of the guide cover 155 extends longitudinally in the axial direction of the rack 130, so that the support element 151 can be supported by the support groove 155-1 when the rack 130 moves in the axial direction.

[0263] The support groove 155-1 can, for example, without being limited to, have a trapezoidal shape with a width that increases in the direction of the support element 151.

[0264] The support element 151 can have a trapezoidal shape with a width that decreases from the outer circumferential surface of the rack 130 in the direction of the support groove 155-1.

[0265] Two opposing side surfaces of the support groove 155-1 can be in close contact with and supported by the support element 151, and an inner upper surface of the support groove 155-1, which is positioned between the two opposing side surfaces of the support groove 155-1, can be spaced away from one end of the support element 151.

[0266] A coating layer can be provided on the support groove 155-1 or the support element 151 and can be made of a low-friction material, such as fluoropolymer or ceramic, to reduce or minimize friction.

[0267] The support groove 155-1 may contain grease to minimize friction with the support element 151.

[0268] The guide cover 155 can be attached to the rack housing 160 by means of the fastening element 159.

[0269] Furthermore, an elastic element 157 can be arranged between the guide cover 155 and the rack housing 160, which is penetrated by the fastening element 159 and is configured to elastically support the guide cover 155 and the rack housing 160.

[0270] A sealing element or seal 158 can be applied to the ends of the guide cover 155 and the outer circumferential surface of the rack housing 160 to prevent moisture or dust from being introduced from the outside of the rack housing 160.

[0271] The support element 151 and the guide cover 155 can have a predetermined stiffness and elasticity and can be made of one or more materials selected from a group consisting of polyacetal (POM), polyamide (PA), polycarbonate (PC), polyimide (PI), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) and phenolformaldehyde (PF).

[0272] In a Fig. In the illustrated embodiment 19, the anti-rotation element 150 can be supported by a housing cover 154, which is coupled to the rack housing 160, and the outer circumferential surface of the rack 130, thereby preventing the rack 130 from rotating about the central axis of the rack 130.

[0273] The anti-rotation element 150 can include the support element 151, which supports the outer circumferential surface of the rack 130, wherein the housing cover 154 is attached to the rack housing 160 and has the inner circumferential surface to which the support element 151 is coupled, and the fastening element 159, which is configured to fasten the housing cover 154 to the rack housing 160.

[0274] A rack support groove 134, through which the support element 151 is supported, is formed on the outer circumferential surface of the rack 130.

[0275] The rack support groove 134 extends longitudinally in the axial direction of the rack 130, so that the support element 151 can be supported by the rack support groove 134 when the rack 130 moves in the axial direction.

[0276] The rack support groove 134 can be recessed from the outer circumferential surface of the rack 130 and can have a curved surface or a flat surface.

[0277] The rack housing 160 can have an opening at a position corresponding to or facing the rack support groove 134, and the housing cover 154 is coupled to the opening of the rack housing 160.

[0278] A cover support groove 156, in which the support element 151 is positioned, can be formed on the inner circumferential surface of the housing cover 154.

[0279] The rack support groove 134 can, for example, but is not limited to, have a trapezoidal shape with a width that increases towards the housing cover 154.

[0280] The support element 151 can have a trapezoidal shape with a width that decreases from the cover support groove 156 towards the rack support groove 134.

[0281] Two opposing side surfaces of the rack support groove 134 can be in close contact with and supported by the support element 151, and an inner surface of the rack support groove 134, which is positioned between the two opposing side surfaces of the rack support groove 134, can be spaced away from the end of the support element 151.

[0282] A coating layer can be provided on the rack support groove 134 or the support element 151 and can be made of a low-friction material, such as fluoropolymer or ceramic, to reduce or minimize friction.

[0283] The rack support groove 134 can be greased or filled to reduce or minimize friction with the support element 151.

[0284] The housing cover 154 can be attached to the rack housing 160 by means of the fastening element 159.

[0285] The seal or sealing element 158 ​​can be applied to the end section of the housing cover 154 and the outer circumferential surface of the rack housing 160 to prevent moisture or dust from being introduced from the outside of the rack housing 160.

[0286] The support element 151 and the housing cover 154 can have a predetermined stiffness and elasticity and can be made of one or more materials selected from a group consisting of polyacetal (POM), polyamide (PA), polycarbonate (PC), polyimide (PI), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) and phenolformaldehyde (PF).

[0287] As described above, a steer-by-wire steering device according to some embodiments of the present disclosure can include a plurality of motors and provide a steering force for a rack. Additionally, a steer-by-wire steering device according to some embodiments of the present disclosure can prevent unnecessary rotation of a rack, even though a means for preventing rack rotation is provided and the pinion is excluded.

[0288] The following describes various embodiments of a method for determining the position of a rack in a steer-by-wire steering system. Some embodiments of the rack-determining method described below can be applied independently of the motor configuration, position, and shape mentioned above. However, certain embodiments of the rack-determining method can be applied to the aforementioned motor configuration, position, and shape. Furthermore, the rack-determining method can be applied in exemplary embodiments of the steer-by-wire steering system that do not include the anti-rotation element, or it can be applied in any type of anti-rotation element.

[0289] In the steer-by-wire steering system, the electronic control unit 110 can control the operating processes of one or more drive motors (e.g., 145 and 147). For example, the electronic control unit 110 can receive information or one or more signals from one or more sensors assigned to the vehicle and control one or more drive motors based on the information or signals received from one or more sensors.

[0290] One or more sensors include various sensors, such as a steering angle sensor, a steering torque sensor, a vehicle speed sensor, a rack position sensor, and any type of sensor that is attached to or provided in the vehicle in connection with the vehicle's steering system. However, as described above, according to some embodiments of the present disclosure, the pinion may not be included in the steer-by-wire steering device if the rack is configured to be moved by the first motor and the second motor. In this case, the rack position sensor, which is configured to detect an absolute position of the rack, may not be included in the steer-by-wire steering device.Alternatively, the rack position sensor, configured to detect the absolute position of the rack, can be included in a gearbox configured to connect the first and / or second motor to the rack.

[0291] First, various embodiments for identifying the absolute position (or an absolute angle) of the rack are described. Then, an embodiment is described that includes an absolute angle sensor configured to detect the absolute position (or an absolute angle) of the rack.

[0292] The electronic control unit 110 can control the operation of the steering shaft motor 120. The electronic control unit 110 can be configured as a single, physically integrated chip. Alternatively, the electronic control unit 110 can be configured using a variety of chips. For example, each of the reaction force motor, drive motor, main control unit, and any component of the steer-by-wire steering system includes one or more chips to perform its necessary operations.

[0293] In addition, the electronic control unit 110 can control the direction of travel of the vehicle according to the driver's steering intention by controlling the operating processes of the multitude of drive motors (e.g. 145 and 147).

[0294] Multiple electronic control units 110 can be provided in the steer-by-wire steering system to ensure redundancy and to perform the same operation consistently or stably, even if any one of the multiple electronic control units 110 is abnormal or inoperative. Alternatively, the multiple electronic control units 110 include a master electronic control unit and a sub-electronic control unit. The master electronic control unit can control the operation of the steer-by-wire steering system when the master electronic control unit is in a normal state, and the sub-electronic control unit can control the operation of the steer-by-wire steering system when the master electronic control unit is abnormal or inoperative.

[0295] The electronic control unit 110 can control the vehicle's steering in response to various pieces of information. The steer-by-wire (SBW) system may require precise information regarding the position of the rack and pinion to accurately control the vehicle's steering, especially when multiple motors are used to drive the rack.

[0296] For this purpose, the electronic control unit 110 can receive the rack position information from the rack position sensor. Alternatively, the electronic control unit 110 can estimate the rack position using the positions of the multiple motors without the rack position sensor.

[0297] For example, the electronic control unit 110 can receive rotation information from each of the motors from the plurality of motor position sensors. In an exemplary embodiment of the present disclosure, the motor rotation information can include rotation information from the first motor and rotation information from the second motor. The rotation information of the first motor can be received from a first motor position sensor that is contained in or associated with the first motor. The rotation information of the second motor can be received from a second motor position sensor that is contained in or associated with the second motor.

[0298] The motor position sensor can detect rotational information from each of the motors. It can detect the rotation of a motor shaft. Alternatively, it can detect the rotation of any rotatable component or structure connected to or associated with the motor shaft. The sensor can detect a rotational position between 0 and 360 degrees relative to the motor's rotation. For example, it can measure the angle of rotation and / or the position of the motor.

[0299] For example, the motor position sensor can be an optical sensor or encoder configured to detect a position by emitting light onto a rotating plate or disk. Alternatively, the motor position sensor can be a magnetic sensor or encoder configured to measure the position of a rotor by detecting a magnetic field. Alternatively, the motor position sensor can be an incremental sensor or encoder configured to measure a change in the relative position of a rotor by outputting a predetermined pulse. Alternatively, the motor position sensor can be an absolute sensor or encoder configured to measure the absolute position of a rotor by outputting a unique value with respect to a given position. The motor position sensor according to certain embodiments of this disclosure can provide a precise position and / or speed of the motor.

[0300] For example, a Hall sensor that measures the position of a motor by detecting a change in the magnetic flux of a rotor to which a permanent magnet or magnetic material is attached or mounted can be used as the motor position sensor. The motor of the steer-by-wire steering device can be a brushless direct current (BLDC) motor, and three Hall sensors with a phase difference of 120 degrees or 60 degrees can be arranged or configured to detect the position of the motor. Additionally, the motor position sensor can be a resolver configured to measure a position analogously by using a change in voltage, or an inductive position sensor configured to detect a position using an electromagnetic induction principle. In the present disclosure, any type of sensor can be used as the motor position sensor.

[0301] The motor position sensor can measure an absolute position or an absolute angle value based on a specific position of the motor. Alternatively, the motor position sensor can detect a relative position with respect to a reference position. Alternatively, the motor position sensor can measure the electrical position of a rotor in a BLDC or permanent magnet synchronous motor (PMSM).

[0302] A rotation angle in a single revolution is an angle between 0 and 360 degrees, and therefore a rotation angle can only be represented in a single revolution. Consequently, the absolute position of the motor, which lies beyond 360 degrees, cannot be identified because the angle of the motor's rotor resets after a complete revolution. However, there is an absolute motor position sensor that can measure the motor's position over multiple revolutions, but it has a complex configuration and structure and is more expensive.

[0303] Without using an absolute motor position sensor, some embodiments of the present disclosure can detect an absolute position of the rack using at least two motor position sensors that measure a relative position.

[0304] For example, if two motors are moving the same rack and have different rotational speeds, the angles of rotation measured by the two motor position sensors of the two motors can range from 0 degrees to 360 degrees. If the motor position sensor is not an absolute angle sensor, the angle measured by the motor position sensor is not recorded or stored, and the angle of rotation detected by the motor position sensor of the first motor can be between 0 degrees and 360 degrees, and the angle of rotation detected by the motor position sensor of the second motor can also be between 0 degrees and 360 degrees.

[0305] The electronic control unit 110 can receive the rotation angle detected by the motor position sensor of the first motor and the rotation angle detected by the motor position sensor of the second motor. The electronic control unit 110 estimates the absolute position of the rack using the two rotation angles (i.e., motor positions) detected by each of the two motor position sensors of the two motors.

[0306] As described above, in certain embodiments of the present disclosure, the first motor and the second motor are operatively connected to a single ball nut, which is operatively coupled to the rack, and move the rack at different rotational speeds. Although the first motor and the second motor rotate at different speeds, they must therefore rotate the ball nut at the same speed. Therefore, the motor pulley of the first motor and the motor pulley of the second motor can be configured with different gear ratios.

[0307] The transmission ratio can refer, for example, but is not limited to, a ratio of the number of threads or diameters of pulleys. For instance, the transmission ratio can be the ratio between the number of threads or diameter of a motor pulley connected to a motor shaft of the first motor and the number of threads or diameter of a motor pulley connected to a motor shaft of the second motor. There can be a significant difference in the transmission ratio if the diameters of the motor pulleys are different.

[0308] The first motor and the second motor can rotate at different speeds, and the electronic control unit 110 can receive different motor rotation information from the motor position sensors of the first and second motors.

[0309] The electronic control unit 110 can determine the absolute position of the rack using preset information and motor rotation information from the first and second motors.

[0310] For example, the difference in rotational speed between the two motors can vary depending on the absolute position of the rack.

[0311] For example, the electronic control unit 110 can determine the absolute position of the rack by monitoring a change in the rotation information of the two motors. For example, the electronic control unit 110 can determine the position of the rack using equation 1. R=K360×θ+K×n

[0312] R represents a linear position of the rack, θ represents a phase difference between the first rotation information of the first motor and the second rotation information of the second motor, K represents a distance by which the rack is moved while a phase difference between the first rotation information and the second rotation information changes from 0 and becomes 0 the next time the phase difference moves in one direction, and n represents the number of times the phase difference becomes 0 while the rack moves in one direction.

[0313] This means that the electronic control unit 110 can cumulatively identify the position of the rack by consistently monitoring the phase difference between the first rotation information of the first motor and the second rotation information of the second motor and recording the number of times the phase difference becomes 0.

[0314] In another example, the electronic control unit 110 can determine the position of the rack based on a preset reference value. The movable range of the rack is structurally limited. Therefore, the multitude of rack positions corresponding to the first rotation information from the first motor and the second rotation information from the second motor can be calculated in advance and stored in the memory of the electronic control unit 110 in the form of a table or other data formats.

[0315] When the first rotation information from the first motor and the second rotation information from the second motor are received, the electronic control unit 110 can estimate the absolute position of the rack by comparing the first and second rotation information from the first and second motors with pre-stored data. However, in this case, the first and second rotation information must be designed to have different values ​​within a linearly movable range of the rack. Therefore, a difference in the gear ratio between the first and second motors must be set so that the first and second rotation information from the first and second motors do not overlap or correspond to two or more absolute positions of the rack.

[0316] For example, the electronic control unit 110 can estimate the absolute position of the rack using equation 2. A={(first rotation information+m)×first translation ratio}B={(second rotation information+m)×second translation ratio}

[0317] Rack position R = intersection of A and B.

[0318] Here, m is a natural number equal to or greater than 1 and equal to or less than a maximum movement distance of the rack.

[0319] Fig. Figure 20 is a diagram illustrating a procedure for estimating the position of a rack using a difference between first rotation information from a first motor and second rotation information from a second motor. Fig. Figure 20 illustrates a relationship between the first rotation information of the first motor and the second rotation information of the second motor and a linear position of a rack within a movable range of 0 to 75 mm. As described above, the first and second gear ratios can be adjusted so that the first rotation information of the first motor and the second rotation information of the second motor do not overlap or correspond to multiple positions of the rack.

[0320] With reference to Fig. 21, Fig. 22, Fig. 23, Fig. 24, Fig. 25, Fig. 26, Fig. 27, Fig. 28, Fig. 29 to Fig. 30 The first nut pulley 143a has the first nut pulley teeth 143-1 formed on the outer circumferential surface of the first nut pulley 143a, and the second nut pulley 143b has the second nut pulley teeth 143-2 formed on the outer circumferential surface of the second nut pulley 143b and configured with a specific angular offset relative to the helix angle B of the first nut pulley teeth 143-1.

[0321] The helix angles B (also referred to as helical angles or pitch angles) of the first and second nut pulley teeth 143-1 and 143-2 are inclined at predetermined angles with respect to a central axis of the ball nut 141. This configuration is described in detail with reference to Fig. 26, Fig. 27 to Fig. 28 described below.

[0322] The first motor pulley teeth 142-1, which correspond to or are identical with the first mother pulley teeth 143-1, are formed on the outer circumferential surface of the first motor pulley 142a, which is provided on the first motor 145, and the second motor pulley teeth 142-2, which correspond to or are identical with the second mother pulley teeth 143-2, are formed on the outer circumferential surface of the second motor pulley 142b, which is provided on the second motor 147.

[0323] Furthermore, first belt teeth 149-1, which are formed on an inner circumferential surface of the first belt 149a, are formed such that they are identical to or correspond to the first mother pulley teeth 143-1 and the first motor pulley teeth 142-1, and second belt teeth 149-2, which are formed on an inner circumferential surface of the second belt 149b, are formed such that they are identical to or correspond to the second mother pulley teeth 143-2 and the second motor pulley teeth 142-2.

[0324] In this case, the helix angles B of the first and second belt teeth 149-1 and 149-2 are related to the helix angles B of the first and second nut belt pulley teeth 143-1 and 143-2, which are shown in Fig. 26, Fig. 27 to Fig. The illustrations in section 28 are identical. A detailed description of these is omitted below.

[0325] As in Fig. As illustrated in Figure 23, the first nut pulley 143a and the second nut pulley 143b can be integrated with the outer circumferential surface of the ball nut 141.

[0326] This configuration, in which the first pulley teeth 143-1 and the second pulley teeth 143-2 are formed as an integral, one-piece strut on the outer circumferential surface of the ball nut 141, can perform the same function as a configuration in which the first pulley 143a and the second pulley 143b are coupled to the ball nut 141 as separate components. However, the configuration in which the first pulley teeth 143-1 and the second pulley teeth 143-2 are formed as an integral, one-piece strut on the outer circumferential surface of the ball nut 141 can enable a more efficient and simpler manufacturing process compared to the configuration in which the first pulley 143a and the second pulley 143b are coupled to the ball nut 141 as separate components.

[0327] Additionally, as in Fig. Figure 24 illustrates that the first nut pulley 143a and the second nut pulley 143b are integrated or coupled on the outer circumferential surface of the ball nut 141.

[0328] A configuration in which the first and second nut pulley teeth 143-1 and 143-2 are formed as an integral, one-piece strut on the outer circumferential surfaces of the integrated first and second nut pulleys 143a and 143b can perform the same function as a configuration in which the first nut pulley 143a and the second nut pulley 143b are coupled to the ball nut 141 as separate components. However, the configuration in which the first and second nut pulley teeth 143-1 and 143-2 are formed as an integral, one-piece strut on the outer circumferential surfaces of the integrated first and second nut pulleys 143a and 143b can enable a more efficient and simpler manufacturing process compared to the configuration in which the first nut pulley 143a and the second nut pulley 143b are coupled to the ball nut 141 as separate components.

[0329] Furthermore, as in Fig. Figure 25 illustrates that the first nut pulley 143a and the second nut pulley 143b are coupled to the outer circumferential surface of the ball nut 141.

[0330] With reference to Fig. 26, Fig. 27 to Fig. 28 The helix angles B of the first and second nut pulley teeth 143-1 and 143-2 are described in an exemplary embodiment in which the first nut pulley 143a and the second nut pulley 143b are coupled to the outer circumferential surface of the ball nut 141.

[0331] As in Fig. As illustrated in Figure 26, the helix angles B of the first and second nut pulley teeth 143-1 and 143-2 can be formed as positive values ​​clockwise with respect to a central axis S1 of the ball nut 141.

[0332] That is, a direction P1 in which the first nut pulley teeth 143-1 and the second nut pulley teeth 143-2 are in a direction (e.g. a direction to the left in Fig. 26) the central axis S1 of the ball nut 141 or a central axis of the rack 130 can be formed at the helix angle B which corresponds to the positive value clockwise.

[0333] In this embodiment, the helix angles B of the first and second nut pulley teeth 143-1 and 143-2 can be formed in a range of 0° < B < 90°, and the helix angles B of the first and second nut pulley teeth 143-1 and 143-2 can be configured with a certain angular offset, so that the helix angles B of the first and second nut pulley teeth 143-1 and 143-2 are not equal to each other.

[0334] Additionally, as in Fig. Figure 27 illustrates that the helix angles B of the first and second nut pulley teeth 143-1 and 143-2 are formed as negative values ​​counterclockwise with respect to the central axis S1 of the ball nut 141.

[0335] That is, the direction P1, in which the first nut pulley teeth 143-1 and the second nut pulley teeth 143-2 are in relation to a direction (e.g. a direction to the left in Fig. 27) the central axis S1 of the ball nut 141 or the central axis of the rack 130 can be formed at the helix angle B which corresponds to the negative value counterclockwise.

[0336] In this embodiment, the helix angles B of the first and second nut pulley teeth 143-1 and 143-2 can be formed in a range of 0° < B < - 90°, and the helix angles B of the first and second nut pulley teeth 143-1 and 143-2 can be configured with a certain angular offset, so that the helix angles B of the first and second nut pulley teeth 143-1 and 143-2 are not equal to each other.

[0337] Furthermore, as in Fig. Figure 28 illustrates that the helix angle B of the first nut pulley teeth 143-1 can be formed as a positive value clockwise based on the central axis of the ball nut 141, and the helix angle B of the second nut pulley teeth 143-2 can be formed as a negative value counterclockwise with respect to the central axis of the ball nut 141.

[0338] That is, the direction P1, in which the first nut pulley teeth 143-1 are located in relation to a direction (e.g. in a direction to the left in Fig. 28) the central axis S1 of the ball nut 141 or the central axis of the rack 130 can be formed at the helix angle B which corresponds to the positive value clockwise, and the direction P1 in which the second nut pulley teeth 143-2 are formed can be formed at the helix angle B which corresponds to the negative value counterclockwise.

[0339] In this embodiment, the helix angle B of the first nut pulley teeth 143-1 can be formed in a range of 0° < B < 90°, and the helix angle B of the second nut pulley teeth 143-2 can be formed in a range of 0° < B < -90°. Since the helix angle B of the first nut pulley teeth 143-1 has a positive value, and the helix angle B of the second nut pulley teeth 143-2 has a negative value, the helix angles B are always formed in such a way that they are shifted.

[0340] Additionally, although not illustrated in the drawings, the helix angle B of the first nut pulley teeth 143-1 can be formed as a negative counterclockwise value with respect to the central axis of the ball nut 141, and the helix angle B of the second nut pulley teeth 143-2 can be formed as a positive clockwise value with respect to the central axis of the ball nut 141. Since this embodiment corresponds to a case in which the Fig. Since view 9 is reversed, a detailed description of it is omitted.

[0341] Therefore, the helix angle B of the first nut pulley teeth 143-1 and the helix angle B of the second nut pulley teeth 143-2 are each designed such that they are shifted as a positive and a negative value, thereby reducing noise and vibration caused by gaps between the first nut pulley teeth 143-1 and the first belt pulley teeth 142-1 and between the second nut pulley teeth 143-2 and the second belt pulley teeth 142-2, and reducing the occurrence of slippage or tooth jump even in the case of high force transmission.

[0342] Additionally, as in Fig. 26, Fig. 27 to Fig. Figure 28 illustrates that the first mother pulley teeth 143-1 and the second mother pulley teeth 143-2 are arranged so that they are spaced apart from each other in a circumferential direction, but the first mother pulley 143a and the second mother pulley 143b can be adjacent to each other.

[0343] That is, the ends of the first nut pulley teeth 143-1 and the ends of the second nut pulley teeth 143-2, which are arranged in a direction in which the first nut pulley 143a and the second nut pulley 143b face each other, are arranged such that they are spaced apart from each other in the circumferential direction, and this configuration can perform the same function during rotation in the circumferential direction as a configuration in which the first nut pulley teeth 143-1 and the second nut pulley teeth 143-2 are continuously arranged on a single pulley.

[0344] Therefore, operating noise and vibrations of the first nut pulley 143a, the second nut pulley 143b, the first belt and the second belt 149b can be reduced.

[0345] Furthermore, the number of teeth on the first motor pulley 142-1 and the number of teeth on the second motor pulley 142-2 may differ, and the number of teeth on the first nut pulley 143-1 and the number of teeth on the second nut pulley 143-2 may be the same.

[0346] That is, the first motor pulley teeth 142-1 and the second motor pulley teeth 142-2 can be configured with circumferential pitches that are the same as those of a gear module, while differing from the gear module in pitch circle diameters and number of teeth, and the first mother pulley teeth 143-1 and the second mother pulley teeth 143-2 can have circumferential pitches that are the same as those of the gear module as well as pitch circle diameters and number of teeth that correspond to the gear module.

[0347] As in Fig. 1 and Fig. As illustrated in Figure 2, the first motor 145 can have the first motor sensor 145s, which is configured to detect the rotational position of the shaft 145a of the first motor 145, and the second motor 147 can have the second motor sensor 147s, which is configured to detect the rotational position of the shaft 147a of the second motor 147.

[0348] When the first motor 145 is operating, the first motor sensor 145s detects a direction of rotation and / or an angle of rotation of the shaft 145a of the first motor 145, and the first motor sensor 145s transmits a signal relating to the direction of rotation and / or the angle of rotation of the shaft 145a of the first motor 145 (e.g. a first position value) to the electronic control unit 110.

[0349] When the second motor 147 is operating, the second motor sensor 147s detects a direction of rotation and / or an angle of rotation of the shaft 147a of the second motor 147, and the second motor sensor 147s transmits a signal relating to the direction of rotation and / or the angle of rotation of the shaft 147a of the second motor 147 (e.g. a second position value) to the electronic control unit 110.

[0350] Therefore, the electronic control unit 110 can determine a displacement position or linear position of the rack 130 based on a first position value received from the first motor sensor 145s and a second position value received from the second motor sensor 147s, and control an output signal or output value to be transmitted to the first motor 145 and the second motor 147 in order to control the first motor 145 and the second motor 147.

[0351] That is, the electronic control unit 110 sets an angle defined between a reference point of the shaft 145a of the first motor 145 in a stopped state of the first motor 145 and a reference point of the shaft 147a of the second motor 147 in a stopped state of the second motor 147 as a reference position value, sets an angle defined between the reference point of the shaft 145a of the first motor 145 and the reference point of the shaft 147a of the second motor 147 after the operating operations of the first and second motors 145 and 147 as an operating position value, and determines the displacement position or linear position of the rack 130 based on a difference between the reference position value and the operating position value.

[0352] Therefore, the position of the rack 130 can be calculated using the reference position values ​​and the operating position values ​​of the first and second motors 145 and 147 without a rack position sensor.

[0353] The difference between the reference position value and the operating position value can be set from 0° to 360°. A maximum displacement of the rack 130 is set within this range. The electronic control unit 110 determines the displacement or linear position of the rack 130 based on at least one of the following: a rotation ratio between the first motor pulley 142a and the first nut pulley 143a, a rotation ratio between the second motor pulley 142b and the second nut pulley 143b, an outer diameter and an inner diameter of the ball nut 141, an outer diameter of the rack 130, or a helix angle between a rack screw groove and a nut screw groove.

[0354] Additionally, the electronic control unit 110, like the method mentioned above, can determine the displacement position or linear position of the rack 130 by setting the difference between the reference position value and the operating position value as a movement value and comparing the movement value with preset data. The movement value can be set from 0° to 360°, and the maximum displacement of the rack 130 is set within this range.

[0355] The preset data can be data in which the displacement amount of the rack 130 is stored according to the movement value determined on the basis of at least one of the pitch circle diameters and the number of teeth of the first and second motor pulleys 142a and 142b, the pitch circle diameters and the number of teeth of the first and second nut pulleys 143a and 143b, the outer and inner diameter of the ball nut 141 or the outer diameter of the rack 130.

[0356] As described above, the first motor pulley teeth 142-1 and the second motor pulley teeth 142-2 are configured to differ in number, whereas the first nut pulley teeth 143-1 and the second nut pulley teeth 143-2 are configured to be the same in number, so that the electronic control unit 110 can control the output value to be transmitted to the first motor 145 and the second motor 147 by determining the displacement position or linear position of the rack 130 based on the first position value transmitted by the first motor sensor 145s and the second position value transmitted by the second motor sensor 147s.

[0357] Additionally, the first motor pulley teeth 142-1 and the second motor pulley teeth 142-2 can be configured to have the same number of teeth, while the first nut pulley teeth 143-1 and the second nut pulley teeth 143-2 can be configured to differ in number.

[0358] This means that the first motor pulley teeth 142-1 and the second motor pulley teeth 142-2 can be configured with circumferential pitches, pitch circle diameters and tooth counts that are the same as those of the gear module, whereas the first mother pulley teeth 143-1 and the second mother pulley teeth 143-2 can have circumferential pitches that are the same as the gear module, but differ from the gear module in pitch circle diameters and number of teeth.

[0359] Furthermore, the first motor 145 can have the first motor sensor 145s, which is configured to detect the rotational position of the shaft 145a of the first motor 145, and the second motor 147 can have the second motor sensor 147s, which is configured to detect the rotational position of the shaft 147a of the second motor 147.

[0360] Therefore, the electronic control unit 110 can control the output value to be transmitted to the first motor 145 and the second motor 147 by determining the displacement position or linear position of the rack 130 by the above-mentioned process based on the first position value transmitted by the first motor sensor 145s and the second position value transmitted by the second motor sensor 147s.

[0361] Additionally, the first motor pulley teeth 142-1 and the second motor pulley teeth 142-2 can be configured to differ in number, and likewise the first nut pulley teeth 143-1 and the second nut pulley teeth 143-2 can also be configured to differ in number.

[0362] That is, the first motor pulley teeth 142-1 and the second motor pulley teeth 142-2 can be configured with circumferential pitches that are the same as those of the gear module, while differing from the gear module in pitch circle diameters and number of teeth, and the first mother pulley teeth 143-1 and the second mother pulley teeth 143-2 can have circumferential pitches that are the same as the gear module, but differ from the gear module in pitch circle diameters and number of teeth.

[0363] Furthermore, the first motor 145 can have the first motor sensor 145s, which is configured to detect the rotational position of the shaft 145a of the first motor 145, and the second motor 147 can have the second motor sensor 147s, which is configured to detect the rotational position of the shaft 147a of the second motor 147.

[0364] Therefore, the electronic control unit 110 can control the output value to be transmitted to the first motor 145 and the second motor 147 by determining the displacement position or linear position of the rack 130 by the above-mentioned process based on the first position value transmitted by the first motor sensor 145s and the second position value transmitted by the second motor sensor 147s.

[0365] As in Fig. As illustrated in Figure 26, a gap t in the axial direction can be provided between the first nut pulley 143a and the second nut pulley 143b.

[0366] The gap t provided between the first nut pulley 143a and the second nut pulley 143b prevents interference between the pulleys and allows the movements of the first and second belts 149a and 149b to be maintained stably when the first nut pulley 143a and the second nut pulley 143b are coupled to the outer circumferential surface of the ball nut 141 and rotate together with the ball nut 141.

[0367] With reference to Fig. 29 and Fig. 30 together with Fig. 23, Fig. 24, Fig. 25 to Fig. 26. Anti-rotation elements 160 can be coupled between the ball nut 141 and the first nut pulley 143a and between the ball nut 141 and the second nut pulley 143b.

[0368] It may be necessary for the first nut pulley 143a and the second nut pulley 143b to have predetermined degrees of stiffness and elasticity and to be made of one or more materials selected from a group consisting of polyacetal (POM), polyamide (PA), polycarbonate (PC), polyimide (PI), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) and phenolformaldehyde (PF).

[0369] The anti-rotation elements 160, which are made of a metallic material such as steel, can prevent the first nut pulley 143a and the second nut pulley 143b from being in neutral or from separating from the ball nut 141 when the first nut pulley 143a and the second nut pulley 143b are coupled to the outer circumferential surface of the ball nut 141 and rotate together with the ball nut 141.

[0370] The anti-rotation element 160 can be integrated by forming it with the first nut pulley 143a and the second nut pulley 143b.

[0371] The anti-rotation element 160 can include a cylindrical section 161 coupled to the outer circumferential surface of the end of the ball nut 141 and a pulley support section 163 bent from one end of the cylindrical section 161, extending in a different direction from the cylindrical section 161, such as a radial direction, and having projecting sections 165 arranged on an outer circumferential surface of the pulley support section 163 and spaced apart from each other in a circumferential direction.

[0372] The pulley support section 163 has the projecting sections 165 and recessed sections 167, which are arranged alternately and formed continuously in the circumferential direction, and the pulley support section 163 can be integrated by forming in a state in which the pulley support section 163 is inserted into a first support end section 146 which is provided in the first nut pulley 143a.

[0373] Additionally, the pulley support section 163 can be integrated by forming in a state in which the pulley support section 163 is inserted into a second support end section 148, which is provided in the second nut pulley 143b.

[0374] Therefore, the anti-rotation element 160 is securely integrated with the first nut pulley 143a and the second nut pulley 143b by means of a molded material provided between the protruding sections 165 and the recessed sections 167.

[0375] Furthermore, as in Fig. Figure 29 illustrates that a large diameter section 141-1 with an increased outer circumference diameter may be provided at one end of the ball nut 141, while a small diameter section 141-2 with a decreased outer circumference diameter may be provided at the other end of the ball nut 141.

[0376] Furthermore, the cylindrical section 161 of the anti-rotation element 160, which is coupled to the first nut pulley 143a, can be press-fitted onto the outer circumferential surface of the large diameter section 141-1, and the cylindrical section 161 of the anti-rotation element 160, which is coupled to the second nut pulley 143b, can be press-fitted onto the outer circumferential surface of the small diameter section 141-2.

[0377] As described above, the cylindrical sections 161 of the anti-rotation elements 160, which are coupled to the first and second nut pulleys 143a and 143b, are each press-fitted to the large diameter section 141-1 and the small diameter section 141-2, respectively, thus preventing the first nut pulley 143a and the second nut pulley 143b from being idle or from separating from the ball nut 141 when the ball nut 141 rotates.

[0378] Additionally, during the assembly of the first nut pulley 143a and the second nut pulley 143b on the ball nut 141, the first nut pulley 143a and the second nut pulley 143b can pass through the small diameter section 141-2 and the large diameter section 141-1 one after the other to be precisely positioned for assembly.

[0379] As described above, according to some embodiments of the present disclosure, a steering device can be stable and effective in reducing noise and vibration.

[0380] The above description has been presented to enable any person skilled in the art to make and use the technical idea of ​​the present disclosure and has been provided in the context of a specific application and its requirements. Various modifications, additions, and substitutions of the described embodiments will be readily apparent to the person skilled in the art, and the general principles defined here can be applied to other embodiments and applications without departing from the fundamental idea and scope of the present disclosure. The above description and the accompanying drawings provide an example of the technical idea of ​​the present disclosure for illustrative purposes only. That is to say, the disclosed embodiments are intended to illustrate the scope of the technical idea of ​​the present disclosure.Therefore, the scope of the present disclosure is not limited to the embodiments shown, but is to be assigned to the broadest scope in accordance with the claims. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] KR 10-2024-0184697

[0001] KR 10-2025-0026967

[0001] KR 10-2025-0026974

[0001] KR 10-2025-0134620

[0001]

Claims

[1] Vehicle steering device comprising: a ball nut which is operationally coupled to a rack and is configured to move the rack linearly by rotating the ball nut; a first nut pulley provided on an outer surface of the ball nut and having first nut pulley teeth formed on an outer surface of the first nut pulley; a second nut pulley provided on the outer surface of the ball nut and having second nut pulley teeth formed on an outer surface of the second nut pulley, wherein the second nut pulley teeth are configured with a helix angle offset relative to a helix angle of the first nut pulley teeth; a first motor pulley of a first motor with first motor pulley teeth that are identical to the first mother pulley teeth; and a second motor pulley of a second motor with second motor pulley teeth that are identical to the second mother pulley teeth. [2] Vehicle steering device according to claim 1, wherein the first nut pulley and the second nut pulley are integrally formed on the outer surface of the ball nut. [3] Vehicle steering device according to claim 1, wherein the first nut pulley and the second nut pulley are integrally formed and coupled to the outer surface of the ball nut. [4] Vehicle steering device according to claim 1, wherein the first nut pulley and the second nut pulley are attached to the outer surface of the ball nut. [5] Vehicle steering device according to claim 1, wherein the helix angle of the first nut pulley teeth and a helix angle of the second nut pulley teeth are configured as positive values ​​clockwise with respect to a central axis of the ball nut. [6] Vehicle steering device according to claim 1, wherein the helix angle of the first nut pulley teeth and a helix angle of the second nut pulley teeth are configured as negative counterclockwise values ​​with respect to a central axis of the ball nut. [7] Vehicle steering device according to claim 1, wherein the helix angle of the first nut pulley teeth is configured as a positive value clockwise with respect to a central axis of the ball nut and the helix angle of the second nut pulley teeth is configured as a negative value counterclockwise with respect to the central axis of the ball nut. [8] Vehicle steering device according to claim 1, wherein the helix angle of the first nut pulley teeth is configured as a negative counterclockwise value with respect to a central axis of the ball nut and the helix angle of the second nut pulley teeth is configured as a positive clockwise value with respect to the central axis of the ball nut. [9] Vehicle steering device according to claim 1, wherein the first nut pulley teeth and the second nut pulley teeth are arranged such that they are spaced apart from each other. [10] Vehicle steering device according to claim 1, wherein a number of the first motor pulley teeth and a number of the second motor pulley teeth differ from each other and a number of the first mother pulley teeth and a number of the second mother pulley teeth are the same. [11] Vehicle steering device according to claim 1, wherein a number of the first motor pulley teeth and a number of the second motor pulley teeth are the same and a number of the first mother pulley teeth and a number of the second mother pulley teeth are different from each other. [12] Vehicle steering device according to claim 1, wherein a number of the first motor pulley teeth and a number of the second motor pulley teeth differ from each other and a number of the first mother pulley teeth and a number of the second mother pulley teeth differ from each other. [13] Vehicle steering device according to claim 4, wherein a gap is provided between the first nut pulley and the second nut pulley. [14] Vehicle steering device according to claim 4, wherein a first anti-rotation element is coupled between the ball nut and the first nut pulley and a second anti-rotation element is coupled between the ball nut and the second nut pulley. [15] Vehicle steering device according to claim 14, wherein the first anti-rotation element is integrated with the first nut pulley by forming. [16] Vehicle steering device according to claim 14, wherein the second anti-rotation element is integrated with the second nut pulley by forming. [17] Vehicle steering device according to claim 14, comprising at least one of the first and the second anti-rotation element: a cylindrical section coupled to an outer surface of an end section of the ball nut; and a pulley support section extending from the cylinder section in a direction other than a central axis of the cylinder section and having projecting sections spaced apart from each other on an outer circumferential surface of the pulley support section and in a circumferential direction. [18] Vehicle steering device according to claim 17, wherein one end of the ball nut has a large diameter section with an enlarged outer diameter and the cylinder section coupled to the first nut pulley is press-fitted onto an outer surface of the large diameter section. [19] Vehicle steering device according to claim 17, wherein another end of the ball nut has a small diameter section having a smaller outer diameter than the large diameter section and the cylinder section coupled to the second nut pulley is press-fitted onto an outer surface of the small diameter section. [20] Vehicle, comprising: a ball nut which is operationally coupled to a rack and is configured to move the rack linearly by rotating the ball nut; a first nut pulley provided on an outer surface of the ball nut and having first nut pulley teeth formed on an outer surface of the first nut pulley; a second nut pulley provided on the outer surface of the ball nut and having second nut pulley teeth formed on an outer surface of the second nut pulley, wherein the second nut pulley teeth are configured with a helix angle offset relative to a helix angle of the first nut pulley teeth; a first motor pulley of a first motor with first motor pulley teeth that are identical to the first mother pulley teeth; and a second motor pulley of a second motor with second motor pulley teeth that are identical to the second mother pulley teeth; a first belt coupled to the first mother pulley and the first engine pulley; a second belt coupled to the second nut pulley and the second engine pulley; a first motor sensor configured to detect a rotational position of the first motor; a second motor sensor configured to detect a rotational position of the second motor; and a controller that is configured to control the first and second motors.

Images