Steering apparatus of vehicle comprising long stroke ball slide structure

Abstract

According to the embodiments, a steering device for an automobile may be provided, comprising: an inner tube accommodating a steering shaft; an outer tube accommodating the inner tube; a ball slide interposed between the inner tube and the outer tube and supported on the outer surface of the inner tube and the inner surface of the outer tube, and including a ball and a retainer supporting the ball; a nut portion coupled to the front end of the inner tube; a ball screw engaging with the nut portion; and a driving portion including a motor for rotating the ball screw.

Description

Technology Field

[0001] The present embodiments relate to a steering system for an automobile, and more specifically, to a steering system for an automobile including a long-stroke ball slide structure. Background Technology

[0002] Generally, the steering system of a vehicle includes a telescopic structure that can adjust the degree of protrusion of the steering wheel and / or a tilt structure that can adjust the angle of the steering wheel so that the driver can adjust the degree of protrusion and the angle of inclination of the steering wheel according to their height or body type.

[0003] Recently, the development of autonomous vehicles capable of finding their way to a destination on their own without the driver operating the steering wheel, accelerator, or brakes is underway, and there is a demand to secure more space for the convenience of the driver sitting in the driver's seat during autonomous driving.

[0004] To this end, numerous attempts are being made to increase the teles-in stroke by modifying the existing telescopic structure. In other words, by increasing the teles-in stroke to retract the steering wheel into the vehicle's dashboard, a larger space can be secured in the driver's seat.

[0005] The steering system generally has a structure in which steering tubes overlap, and telescopic movement is performed as the overlapped steering tubes extend or retract. However, there is a problem in that the rigidity of the steering system, particularly torsional rigidity, decreases as the total telescopic stroke increases. The problem to be solved

[0006] The present embodiments are conceived from the background described above and relate to a steering device for an automobile that can stably perform long-stroke telescopic movement with improved rigidity through a simple structure. means of solving the problem

[0007] According to the embodiments, a steering device for an automobile may be provided, comprising: an inner tube accommodating a steering shaft; an outer tube accommodating the inner tube; a ball slide interposed between the inner tube and the outer tube and supported on the outer surface of the inner tube and the inner surface of the outer tube, and including a ball and a retainer supporting the ball; a nut portion coupled to the front end of the inner tube; a ball screw engaging with the nut portion; and a driving portion including a motor for rotating the ball screw. Effects of the invention

[0008] According to the embodiments, a steering device for an automobile can be provided that has improved rigidity with a simple structure and can stably perform long-stroke telescopic movement. Brief explanation of the drawing

[0009] FIG. 1 is a perspective view of a steering device of an automobile according to the embodiments thereof. FIG. 2 is an exploded perspective view of a steering system of an automobile according to the embodiments of the present invention. FIG. 3 is a perspective view of a part of a steering system of an automobile according to the embodiments thereof. FIG. 4 is an exploded perspective view of a part of the steering system of an automobile according to the embodiments. FIG. 5 is a cross-sectional view of a steering device of an automobile according to the embodiments. FIG. 6 is a cross-sectional view of a steering device of an automobile according to the embodiments. FIG. 7 is a cross-sectional view of a steering device of an automobile according to the embodiments. FIG. 8 is a cross-sectional view of a steering device of an automobile according to the embodiments. FIG. 9 is a cross-sectional view of a steering device of an automobile according to the embodiments. Specific details for implementing the invention

[0010] Hereinafter, the present disclosure will be described in detail with reference to the attached drawings. However, this is merely illustrative and the present disclosure is not limited to the specific embodiments described illustratively.

[0011] The following embodiments are provided to more faithfully and completely explain the technical concept of the present disclosure to those skilled in the art to which the present disclosure pertains. Accordingly, the technical concept of the present disclosure is not necessarily limited to the following embodiments. The present disclosure should be understood to broadly include various equivalents, substitutions, modifications, etc., that embody the technical concept to be described below.

[0012] The terms used in the following description are intended to describe specific embodiments more faithfully and completely in the same light as above. Accordingly, the terms used in the following description should not be interpreted to reduce, limit, or restrict the technical scope of the present disclosure.

[0013] In the following description, terms such as "first," "second," etc., may be used to refer to specific components to distinguish them from other components. However, such terms are used for clarity of explanation, and the technical concept of the present disclosure should not be interpreted as being limited by such terms.

[0014] In the following description, singular expressions may be interpreted to include the plural unless explicitly excluded by the context. Furthermore, in the following description, the expression "includes" means that the components, parts, actions, features, steps, numbers, etc. described in the description exist, and does not exclude the addition of one or more other components, parts, actions, features, steps, numbers, etc.

[0015] In the following description, terms related to direction, such as "beneath," "above," "lower," and "upper," may be used to facilitate understanding of the components. However, such terms are provided to facilitate understanding of the present disclosure based on various operations and usage conditions, and should not be interpreted to reduce, limit, or restrict the technical scope of the present disclosure. For example, terms related to direction may be determined from a relative perspective.

[0016] Meanwhile, in the drawings below, the depiction of each component may be exaggerated or omitted for the convenience and clarity of explanation.

[0017] FIG. 1 is a perspective view of a steering device of a vehicle according to the embodiments of the present invention, FIG. 2 is an exploded perspective view of a steering device of a vehicle according to the embodiments of the present invention, FIG. 3 is a perspective view of a part of a steering device of a vehicle according to the embodiments of the present invention, FIG. 4 is an exploded perspective view of a part of a steering device of a vehicle according to the embodiments of the present invention, FIG. 5 is a cross-sectional view of a steering device of a vehicle according to the embodiments of the present invention, FIG. 6 is a cross-sectional view of a steering device of a vehicle according to the embodiments of the present invention, FIG. 7 is a cross-sectional view of a steering device of a vehicle according to the embodiments of the present invention, FIG. 8 is a cross-sectional view of a steering device of a vehicle according to the embodiments of the present invention, and FIG. 9 is a cross-sectional view of a steering device of a vehicle according to the embodiments of the present invention.

[0018] In the description of the steering device (100) of a vehicle according to the present disclosure, the front is described as the front of the vehicle, in the direction toward the front wheels from the steering device, and the rear is described as the rear of the vehicle, in the direction toward the driver from the steering device.

[0019] According to the embodiments, a steering device (100) of an automobile may be provided, comprising an inner tube (110) that accommodates a steering shaft (101), an outer tube (120) that accommodates the inner tube (110), a ball slide (150) that is interposed between the inner tube (110) and the outer tube (120) and includes a ball (152) supported on the outer surface of the inner tube (110) and the inner surface of the outer tube (120) and a retainer (151) that supports the ball (152), a nut portion (131) coupled to the front end of the inner tube (110), a ball screw (132) that engages with the nut portion (131), and a driving portion (130) that includes a motor (133) for rotating the ball screw (132).

[0020] Referring to FIGS. 1 to 4, the steering device (100) of a vehicle according to the present embodiments includes an inner tube (110), an outer tube (120), a ball slide (150), and a driving unit (130). The steering device (100) of a vehicle according to the present embodiments may further include a mounting bracket (140) for being coupled to a vehicle body. A steering shaft (101) is received in the inner tube (110), and a steering wheel (not shown) is coupled to the rear end to transmit steering input from the driver. The telescopic operation of the steering device (100) of a vehicle according to the present embodiments can be performed by the driving unit (130) causing the inner tube (110) and the steering shaft (101) to slide relative to the outer tube (120). In addition, the steering device (100) of the vehicle according to the embodiments may further include a driving unit for tilt operation, and since the structure of the tilt driving unit is the same as generally known, a detailed description is omitted.

[0021] In the steering device (100) of the vehicle according to the embodiments thereof, the front end of the steering shaft (101) may be mechanically connected to the front wheel. Alternatively, the steering device (100) of the vehicle according to the embodiments thereof may be a steer-by-wire type steering device in which the steering shaft (101) and the front wheel are not mechanically connected, and the driver's steering input is converted into an electrical signal to steer the front wheel.

[0022] The steering device (100) of a vehicle according to the embodiments is a long-stroke steering device in which the stroke of the telescopic movement is increased. As one embodiment, the steering device (100) of a vehicle according to the embodiments may be a steering device in which the steering wheel can be stored within the dashboard of the vehicle body. The steering device (100) of a vehicle according to the embodiments may be a steering device in which the teles-in stroke of the steering wheel is increased, thereby securing space in the driver's seat through telescopic movement and improving driver convenience.

[0023] The inner tube (110) accommodates the steering shaft (101), and the outer tube (120) accommodates the inner tube (110). The steering shaft (101) is coupled to the inner tube (110) by a bearing and can slide axially together with the inner tube (110). The front end of the steering shaft (101) may be mechanically connected to the front wheel through a universal joint, or it may not be mechanically connected to the front wheel.

[0024] The inner tube (110) is axially slid relative to the outer tube (120) by the driving unit (130), and the telescopic operation of the steering device (100) of the automobile according to the embodiments can be performed. A ball slide (150) is interposed between the inner tube (110) and the outer tube (120), and the inner tube (110) can be slid relative to the outer tube (120).

[0025] The ball slide (150) includes a ball (152) and a retainer (151). The ball (152) is supported on the outer surface of the inner tube (110) and the inner surface of the outer tube (120), and sliding of the inner tube (110) against the outer tube (120) can be performed. As described below, the ball (152) may form one or more rows arranged along the axial direction. A hole is formed in the retainer (151) in which the ball (152) is rotatably seated, and while seated in the hole of the retainer (151), the ball (152) rotates and the inner tube (110) can slide against the outer tube (120). The ball slide (150) is maintained in a state where the ball (152) is supported on the outer surface of the inner tube (110) and the inner surface of the outer tube (120) when the inner tube (110) slides against the outer tube (120), and a stopper may be formed in the inner tube (110) to prevent the ball slide (150) from coming off the inner tube (110).

[0026] Not only can sliding of the inner tube (110) relative to the outer tube (120) be performed by the balls (152) arranged along the axial direction, but the rigidity and stability of the telescopic operation of the steering device (100) of the vehicle according to the embodiments can also be improved. That is, the inner tube (110) and the outer tube (120) maintain a state supported by the ball slide (150) interposed between them, and a stable state can be maintained by the ball slide (150) even when the telescopic operation is performed or when it is stopped. For example, when the steering device (100) of the vehicle according to the embodiments is tele-out and fully extended, the structure of the steering device (100) of the vehicle according to the embodiments can be stably maintained by the ball slide (150) interposed between the overlapping portion of the inner tube (110) and the outer tube (120).

[0027] The drive unit (130) includes a nut portion (131), a ball screw (132), and a motor (133). The nut portion (131) is coupled to the inner tube (110), and as the ball screw (132) is rotated by the motor (133), the nut portion (131) coupled to the ball screw (132) moves forward or backward, and the inner tube (110) moves axially relative to the outer tube (120) so that a telescopic operation can be performed. The drive unit (130) may further include a reduction gear connecting the motor (133) and the ball screw (132). The nut portion (131) may include a nut that engages directly with the ball screw (132) and a bracket coupled to the nut and the inner tube (110). A stopper may be coupled to the end of the ball screw (132) to prevent the nut portion (131) from coming off. A slit (121) is formed in the outer tube (120) along the movement path of the nut portion (131), and the nut portion (131) passes through the slit (121) and is connected to the front end of the inner tube (110).

[0028] The nut portion (131) is coupled to the front end of the inner tube (110). More specifically, the bracket of the nut portion (131) can be coupled to the front end of the inner tube (110). That is, the inner tube (110) slides relative to the outer tube (120) as the nut portion (131) coupled to the front end of the inner tube (110) moves on the ball screw (132) by driving the motor (133). As the nut portion (131) is coupled to the front end of the inner tube (110), the length of the ball screw (132) for moving the nut portion (131) and the inner tube (110) in the axial direction can be reduced. That is, when the nut portion (131) is coupled to the middle or rear end of the inner tube (110), the length of the ball screw (132) is increased by the amount that the coupling position of the nut portion (131) to the inner tube (110) is moved rearward. However, in the present embodiments, the length of the ball screw (132) for performing telescopic operation can be reduced as the nut portion (131) is coupled to the front end of the inner tube (110).

[0029] As the length of the ball screw (132) is reduced, not only is the cost of manufacturing the ball screw reduced, but the rigidity of the entire structure can also be increased. In particular, for example, when the steering wheel is stored in the vehicle body for the convenience of the driver during autonomous driving, the telescopic stroke of the steering device is required to be increased, and as the telescopic stroke is increased, the length of the ball screw for telescopic operation is required to be increased.

[0030] Unlike conventional steering devices, the steering device (100) of the vehicle according to the embodiments has a nut portion (131) that is coupled to and moved by the ball screw (132) coupled to the front portion of the inner tube (110) rather than the rear portion, so that the length of the ball screw (132) for telescopic operation can be reduced, and thus higher rigidity can be secured in the long stroke structure.

[0031] According to one embodiment, the ball slide (150) may further include an incision (153) that cuts the retainer (151) so that the retainer (151) does not overlap axially with the nut portion (131). The retainer (151) may have a shape that wraps around the inner tube (110) in a circumferential direction, and may have an open shape with an incision (153) formed on one side. Due to the formation of the incision (153) in the retainer (151), telescopic operation can be performed smoothly while the nut portion (131) is coupled to the front end of the inner tube (110). That is, if the nut portion is connected to the rear end of the inner tube as in a conventional structure, the movement path of the nut portion during telescopic operation is not obstructed by the retainer, so an incision is unnecessary. However, in the structure of the present embodiments, since the nut portion (131) is connected to the front end of the inner tube (110), the movement path of the nut portion (131) during telescopic operation can overlap axially with the retainer (151). Therefore, an incision (153) can be formed in the retainer (151) for smooth telescopic operation.

[0032] Referring to FIG. 5, according to one embodiment, the ball (152) can form a first row (511) arranged at one circumferential end of the retainer (151) cut by the cut portion (153), a second row (512) arranged at the other circumferential end, and a third row (513) arranged between the first row (511) and the second row (512). That is, the ball (152) supporting the sliding of the inner tube (110) against the outer tube (120) can form the first row (511), the second row (512), and the third row (513). The third row (513) can be located at the circumferential center of the first row (511) and the second row (512). That is, the circumferential distance between the first row (511) and the third row (513) and the circumferential distance between the second row (512) and the third row (513) may be the same. The inner tube (110) is supported at three points along the circumferential direction with respect to the outer tube (120) by the balls (152) of the first row (511), the second row (512), and the third row (513), and the rigidity and stability of the telescopic operation may be improved. Meanwhile, as shown in FIG. 5, the second row (512) may be located at the lower end of the inner tube (110) and the outer tube (120). Alternatively, as shown in FIGS. 6 to 9, the second column (512) may be located on one side in the circumferential direction at the lower end of the inner tube (110) and the outer tube (120).

[0033] According to one embodiment, a first seating groove (501) and a second seating groove (502) are formed along the axial direction on the outer surface of the inner tube (110) and the inner surface of the outer tube (120), respectively, in which a ball (152) is seated, and the portion where the first seating groove (501) of the inner tube (110) is formed is formed such that the inner surface and the outer surface of the inner tube (110) are bent and protrude in the radial direction relative to the remaining portion, the small diameter portion (522), to form a large diameter portion (521), and the retainer (151) is supported on the outer surface of the large diameter portion (521) and includes a first support portion (531) which is the portion where the ball (152) is supported and a second support portion (532) which is supported on the outer surface of the small diameter portion (522), and the first support portion (531) and the second support portion (532) are The inner and outer surfaces of the retainer (151) can be bent and connected.

[0034] A first seating groove (501) is formed on the outer surface of the inner tube (110), and a second seating groove (502) is formed on the inner surface of the outer tube (120). The first seating groove (501) and the second seating groove (502) are each formed long along the axial direction, and the ball slide (150) supports the sliding of the inner tube (110) with the ball (152) seated in the first seating groove (501) and the second seating groove (502).

[0035] The inner tube (110) includes a large diameter portion (521) and a small diameter portion (522), and the inner tube (110) including the large diameter portion (521) and the small diameter portion (522) can be formed with a uniform radial thickness overall. That is, the large diameter portion (521) is formed with a larger radius than the small diameter portion (522), and the inner and outer surfaces of the inner tube (110) are bent together and formed to protrude radially relative to the small diameter portion (522). As the boundary area between the large diameter portion (521) and the small diameter portion (522) is formed by bending the inner and outer surfaces of the inner tube (110), the rigidity of the inner tube (110), particularly the torsional rigidity, can be improved.

[0036] The first seating groove (501) of the inner tube (110) is formed in the large diameter portion (521). That is, the large diameter portion (521) is formed by bending both ends in the circumferential direction from the small diameter portion (522), and the first seating groove (501) can be formed between both ends of the large diameter portion (521). The first seating groove (501) can be formed by the large diameter portion (521) being recessed. The second seating groove (502) of the outer tube (120) is formed in a position facing the first seating groove (501) in the radial direction.

[0037] The retainer (151) includes a first support member (531) and a second support member (532), and the retainer (151) including the first support member (531) and the second support member (532) can be formed with a uniform radial thickness overall. That is, the first support member (531) supported on the outer surface of the large diameter portion (521) is formed with a larger radius than the second support member (532) supported on the outer surface of the small diameter portion (522), and the inner and outer surfaces of the retainer (151) are bent together and shaped to protrude radially relative to the second support member (532). As the boundary portion between the first support member (531) and the second support member (532) is formed by bending the inner and outer surfaces of the retainer (151), the rigidity of the retainer (151), particularly the torsional rigidity, can be improved.

[0038] Referring to FIG. 6, the large diameter portion (521) of the inner tube (110) may be formed such that one side in the circumferential direction is longer or shorter than the other side in the circumferential direction, based on the area where the first seating groove (501) is formed. That is, based on the area where the first seating groove (501) is formed, the circumferential distance from the first seating groove (501) to one end of the large diameter portion (521) and the circumferential distance to the other end may be different from each other. The drawing illustrates an embodiment in which a large diameter section (521) with a first seating groove (501) formed for seating a first row (511) and a large diameter section (521) with a second seating groove (502) formed for seating a second row (512) are extended clockwise relative to the drawing, and a large diameter section (521) with a second seating groove (502) formed for seating a third row (513) is extended counterclockwise relative to the drawing, that is, all three large diameter sections (521) are extended to one side or the other side in the circumferential direction. Some or all of the plurality of large diameter sections (521) may be formed to extend to one side or the other side in the circumferential direction. By forming at least some of the large diameter sections (521) long in the circumferential direction, the rigidity of the inner tube (110), particularly the torsional rigidity, can be improved.

[0039] Referring to FIG. 7, according to one embodiment, a first bending portion (701) is formed in the inner tube (110) such that the inner and outer surfaces of the inner tube (110) are bent and protrude radially toward the second support portion (532), and a second bending portion (702) is formed in the second support portion (532) such that the inner and outer surfaces of the retainer (151) are bent and protrude radially to engage with the first bending portion (701). Likewise, the inner tube (110) and the retainer (151) each have a constant radial thickness, and the first bending portion (701) and the second bending portion (702) can be formed by bending the inner and outer surfaces of the inner tube (110) and the retainer (151), respectively. These first bend portion (701) and second bend portion (702) can be formed lengthwise along the axial direction.

[0040] The first bend portion (701) and the second bend portion (702) are interlocked in such a way that the second bend portion (702) is inserted into the inner side of the first bend portion (701). Accordingly, the rigidity, particularly the torsional rigidity, of the inner tube (110) and the retainer (151) can be improved. An embodiment is shown in which the first bend portion (701) and the second bend portion (702) are formed on the upper part of the inner tube (110) and the retainer (151) between the first row (511) and the third row (513). Alternatively, the first bend portion (701) and the second bend portion (702) may be formed between the second row (512) and the third row (513), or may be formed on both parts.

[0041] FIG. 8 illustrates an embodiment in which a first bending portion (701) and a second bending portion (702) are formed between the first row (511) and the third row (513), and a large diameter portion (521) in which the second row (512) is formed is extended clockwise with respect to the drawing from the area where the first seating groove (501) is formed.

[0042] Referring to FIG. 9, according to one embodiment, the inner tube (110) may have a third bend (901) formed therein, in which the inner and outer surfaces of the inner tube (110) are bent and protrude radially toward the cut portion (153). While the first bend (701) protrudes toward the second support portion (532) of the retainer (151) and engages with the second bend (702) formed on the second support portion (532), the third bend (901) protrudes radially toward the cut portion (153). The third bend (901) may be provided as one or more. That is, FIG. 9 illustrates an embodiment in which the first bend (701), the second bend (702), and the third bend (901) are provided. By forming a third bend (901) in the inner tube (110), the rigidity of the inner tube (110), particularly the torsional rigidity, can be improved.

[0043] According to a steering system of a vehicle having such a shape, rigidity is improved with a simple structure, and stable long-stroke telescopic movement can be performed.

[0044] The above description is merely an example of applying the principles of the present disclosure, and other configurations may be included without departing from the scope of the present invention.

[0045] Although embodiments of the present disclosure have been described above, those skilled in the art may modify or change the present disclosure in various ways by adding, changing, deleting, or adding components without departing from the technical spirit of the present disclosure as described in the claims, and such modifications or changes shall also be deemed to be included within the scope of the rights of the present disclosure. Explanation of the symbols

[0046] 100: Automotive steering system 101: Steering shaft 110: Inner tube 120: Outer tube 121: Slit 130: Driving part 131: Nut part 132: Ball screw 133: Motor 140: Mounting bracket 150: Ball slide 151: Retainer 152: Ball 153: Incision 501: First seating groove 502: Second seating groove 511: First row 512: Column 2 513: Column 3 521: Daegyeongbu 522: Sogyeongbu 531: 1st Support Section 532: 2nd Support Section 701: 1st bend section 702: 2nd bend section 901: Third bend

Claims

Claim 1 An inner tube accommodating a steering shaft; an outer tube accommodating the inner tube; a ball slide interposed between the inner tube and the outer tube, comprising a ball supported on the outer surface of the inner tube and the inner surface of the outer tube, and a retainer supporting the ball; a driving unit comprising a nut portion coupled to the front end of the inner tube facing the front of the vehicle, a ball screw engaging with the nut portion, and a motor for rotating the ball screw; wherein a first seating groove and a second seating groove for seating the ball are formed along the axial direction on the outer surface of the inner tube and the inner surface of the outer tube, respectively, and the portion of the inner tube where the first seating groove is formed has the inner and outer surfaces of the inner tube bent and protrudes radially relative to the remaining portion, the small diameter portion, to form a large diameter portion, and the retainer is supported on the outer surface of the large diameter portion, and the portion where the ball is supported A steering device for an automobile comprising 1. a support member and a second support member supported on the outer surface of the small diameter member, wherein the first support member and the second support member are connected by bending the inner and outer surfaces of the retainer. Claim 2 A steering device for an automobile according to claim 1, wherein the ball slide further comprises a cut portion that cuts the retainer so that the retainer does not overlap the nut portion in the axial direction. Claim 3 A steering device for an automobile according to claim 2, wherein the ball forms a first row arranged at one circumferential end of the retainer cut by the cut portion, a second row arranged at the other circumferential end, and a third row arranged between the first row and the second row. Claim 4 delete Claim 5 A steering device for an automobile according to claim 1, wherein the large diameter portion of the inner tube is formed such that one side in the circumferential direction is longer or shorter than the other side in the circumferential direction based on the portion where the first seating groove is formed. Claim 6 A steering device for an automobile according to claim 1, wherein the inner tube has a first bend formed therein that is bent at the inner and outer surfaces of the inner tube and protrudes radially toward the second support member, and the second support member has a second bend formed therein that is bent at the inner and outer surfaces of the retainer and protrudes radially to engage with the first bend. Claim 7 ◈Claim 7 was abandoned upon payment of the registration fee.◈ A steering device for an automobile comprising: an inner tube accommodating a steering shaft; an outer tube accommodating the inner tube; a ball slide interposed between the inner tube and the outer tube, comprising a ball supported on the outer surface of the inner tube and the inner surface of the outer tube, and a retainer supporting the ball; a driving unit comprising a nut portion coupled to the front end of the inner tube, a ball screw engaging with the nut portion, and a motor for rotating the ball screw; wherein the ball slide further comprises a cut portion that cuts the retainer so that the retainer does not overlap the nut portion in the axial direction, and the inner tube has a third bend portion formed therein that is bent at the inner surface and the outer surface of the inner tube and protrudes radially toward the cut portion.

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