Steering column for vehicle

Disclosed is a steering column for a vehicle. A steering column for a vehicle according to an embodiment of the present invention includes a housing provided in a vehicle and having an opening formed at one side thereof, a hollow shaft installed in the housing and configured to be movable in an axial direction through the opening of the housing, a roller having an outer peripheral surface configured to press an outer peripheral portion of the hollow shaft, an actuator configured to provide driving power for rotating the roller, and a first shaft configured to rotate relative to the hollow shaft and installed in the hollow shaft so as to be movable together with the hollow shaft, in which when the roller rotates, the hollow shaft and the first shaft are moved by a frictional force generated between the hollow shaft and the roller.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No. 10-2022-0032415, filed on Mar. 16, 2022, the entire contents of which is incorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a steering column for a vehicle, and more particularly, to a steering column for a vehicle that has no limitation in a telescopic operating distance and may improve the spatial utilization of a driver seat.

DESCRIPTION OF THE RELATED ART

In general, a steering column for a vehicle has a function of adjusting a degree to which a steering wheel protrudes and an angle at which the steering wheel is inclined in accordance with a driver's height or body type. The steering column for a vehicle provides a telescopic function and a tilting function to enable the driver to smoothly perform a steering operation.

The steering column for a vehicle in the related art includes a steering shaft having one end inserted into a hollow shaft and the other end coupled to a steering wheel, a housing configured to accommodate the hollow shaft and the steering shaft, and a base frame configured to couple the housing to a vehicle body.

In particular, the steering column for a vehicle in the related art includes a screw shaft extending in a direction parallel to an axial direction of the hollow shaft, coupling components configured to connect the screw shaft and the hollow shaft, and a motor configured to rotate the screw shaft. When the screw shaft rotates, the screw shaft, the steering shaft, and the steering wheel move together in the axial direction, thereby performing the telescopic function.

However, the steering column for a vehicle in the related art has a problem in that a length of the screw shaft provided at a lateral side of the hollow shaft restricts a telescopic operating distance, and a large number of accessory components are required to manufacture the steering column.

Further, the steering column for a vehicle in the related art has a problem in that the length of the screw shaft needs to increase to increase the telescopic operating distance. For this reason, there is a problem in that costs required to manufacture the steering column are increased, and a structural defect such as bending and warping of the screw shaft easily occur.

In addition, recently, as research and development have been conducted on autonomous vehicles, there is a need for a solution for enlarging a driver seat space that can be used by the driver in order to improve convenience and stability for the driver in an autonomous driving situation.

However, in the case of the steering column for a vehicle in the related art, a space for accommodating the screw shaft needs to be additionally provided at the lateral side of the steering shaft, and thus there is a limitation in the telescopic operating distance. For this reason, there is a problem in that a space that can be used by the driver in the driver seat is restricted.

Therefore, there is an acute need to develop a steering column for a vehicle that has no limitation in the telescopic operating distance and may reduce the manufacturing costs and improve the spatial utilization of the driver seat.

SUMMARY OF THE INVENTION

The present invention is proposed to solve these problems and aims to provide a steering column for a vehicle that has a telescopic function of adjusting a degree to which a steering wheel protrudes.

The present invention also aims to provide a steering column for a vehicle that has no limitation in a telescopic operating distance.

The present invention also aims to provide a steering column for a vehicle that may reduce manufacturing costs and the occurrence of a structural defect.

The present invention also aims to provide a steering column for a vehicle that may improve spatial utilization of a driver seat.

Technical problems to be solved by the present invention are not limited to the above-mentioned technical problems, and other technical problems, which are not mentioned above, may be clearly understood from the following descriptions by those skilled in the art to which the present invention pertains.

One aspect of the present invention provides a steering column for a vehicle, the steering column including: a housing provided in a vehicle and having an opening formed at one side thereof; a hollow shaft installed in the housing and configured to be movable in an axial direction through the opening of the housing; a roller having an outer peripheral surface configured to press an outer peripheral portion of the hollow shaft; an actuator configured to provide driving power for rotating the roller; and a first shaft configured to rotate relative to the hollow shaft and installed in the hollow shaft so as to be movable together with the hollow shaft, in which when the roller rotates, the hollow shaft and the first shaft are moved by a frictional force generated between the hollow shaft and the roller.

In this case, the steering column may further include a support member configured to press an outer peripheral surface of the hollow shaft to support the hollow shaft.

In this case, the support member may be disposed opposite to the roller based on the hollow shaft.

In this case, the support member may be provided in plural.

In this case, the plurality of support members may include first and second support members arranged in the axial direction.

In this case, the first and second support members may be respectively disposed at front and rear sides based on the roller when viewed in the axial direction.

In this case, the support member may include: a slip bushing configured to support the hollow shaft; and an elastic member configured to provide an elastic force that allows the slip bushing to support the hollow shaft.

In this case, a through-hole may be formed in the axial direction in the housing, at least a part of the hollow shaft may be accommodated in the housing, and the roller may press the hollow shaft through the through-hole.

In this case, a rotation shaft of the roller and the first shaft may be disposed to be perpendicular to each other.

A friction member may be provided on the outer peripheral surface of the roller.

A groove may be formed in the outer peripheral surface of the roller and correspond to an outer peripheral surface of the hollow shaft.

In this case, the steering column may further include a transmission configured to connect the actuator and the roller.

In this case, a bearing may be provided between the first shaft and the hollow shaft.

In this case, the steering column may further include a second shaft coupled to one end of the first shaft by a spline structure.

Another aspect of the present invention provides a steering column for a vehicle, the steering column including: a housing provided in a vehicle and having an opening formed at one side thereof; a hollow shaft installed in the housing, configured to be movable in an axial direction through the opening of the housing, and having a first gear formed in the axial direction on an outer peripheral surface thereof; a second gear coupled to the first gear; an actuator configured to provide driving power for rotating the second gear; and a first shaft configured to rotate relative to the hollow shaft and installed in the hollow shaft so as to be movable together with the hollow shaft, in which when the second gear rotates, the hollow shaft and the first shaft are moved by the first gear coupled to the second gear.

Still another aspect of the present invention provides a steering column for a vehicle, the steering column including: a housing provided in a vehicle and having an opening formed at one side thereof; a hollow shaft installed in the housing, configured to be movable in an axial direction through the opening of the housing, and having a pressing part formed in the axial direction at one side thereof; a roller having an outer peripheral surface configured to press the pressing part of the hollow shaft; an actuator configured to provide driving power for rotating the roller; and a first shaft configured to rotate relative to the hollow shaft and installed in the hollow shaft so as to be movable together with the hollow shaft, in which when the roller rotates, the hollow shaft and the first shaft are moved by a frictional force generated between the roller and the pressing part of the hollow shaft.

With the above-mentioned configuration, according to the steering column for a vehicle according to the embodiment of the present invention, the first shaft having one end to which the steering wheel may be coupled is movable in the axial direction together with the hollow shaft, such that the telescopic function of adjusting a degree to which the steering wheel protrudes may be performed.

In addition, according to the steering column for a vehicle according to the embodiment of the present invention, the hollow shaft and the first shaft are moved by the frictional force that is generated between the hollow shaft and the roller as the roller for pressing the outer peripheral portion of the hollow shaft rotates. Therefore, there is no limitation in the telescopic operating distance.

In addition, according to the steering column for a vehicle according to the embodiment of the present invention, the telescopic function may be performed by using the roller without including the screw shaft and the components for coupling the screw shaft and the hollow shaft. Therefore, it is possible to reduce the number of required components and the manufacturing costs and minimize the occurrence of a structural defect.

In addition, according to the steering column for a vehicle according to the embodiment of the present invention, the telescopic means may be simply and compactly implemented by using the roller and the actuator. Therefore, it is possible to minimize the space required to perform the telescopic function.

Further, a separate space for accommodating a shaft is not required, which makes it possible to improve the spatial utilization of the driver seat.

The effects of the present invention are not limited to the above-mentioned effects, and it should be understood that the effects of the present invention include all effects that may be derived from the detailed description of the present invention or the appended claims.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the technical field to which the present invention pertains may easily carry out the exemplary embodiment. The present invention may be implemented in various different ways, and is not limited to the embodiments described herein. In the drawings, a part irrelevant to the description will be omitted to clearly describe the present invention, and the same or similar constituent elements will be designated by the same reference numerals throughout the specification.

Terms or words used in the specification and the claims should not be interpreted as being limited to a general or dictionary meaning and should be interpreted as a meaning and a concept which conform to the technical spirit of the present invention based on a principle that an inventor can appropriately define a concept of a term in order to describe his/her own invention by the best method.

In the present application, it will be appreciated that terms “including” and “having” are intended to designate the existence of characteristics, numbers, steps, operations, constituent elements, and components described in the specification or a combination thereof, and do not exclude a possibility of the existence or addition of one or more other characteristics, numbers, steps, operations, constituent elements, and components, or a combination thereof in advance.

Unless otherwise specified, a case in which one constituent element is disposed at “a front side,” “a rear side,” “an upper side,” or “a lower side” of another constituent element includes not only a case in which one constituent element is disposed at “the front side,” “the rear side,” “the upper side,” or “the lower side” of another constituent element while directly adjoining another constituent element, but also a case in which a further constituent element is disposed between one constituent element and another constituent element. In addition, unless otherwise specified, a case in which one constituent element is “connected to” another constituent element includes not only a case in which one constituent element and another constituent element are directly connected to each other, but also a case in which one constituent element and another constituent element are indirectly connected to each other.

A steering column for a vehicle according to an embodiment of the present invention is a steering column for a vehicle in which a first shaft is movable in an axial direction together with a hollow shaft, and the first shaft and the hollow shaft are moved by a frictional force that is generated between the hollow shaft and a roller as the roller rotates while pressing an outer peripheral portion of the hollow shaft, such that a telescopic function may be performed without limitation in an operating distance.

In addition, the steering column for a vehicle according to the embodiment of the present invention is a steering column for a vehicle in which a telescopic means is simply and compactly implemented by using the roller and an actuator, which makes it possible to reduce the manufacturing costs and improve the spatial utilization of a driver seat.

In the following description with reference to the drawings, the directions are defined and described on the basis of coordinate axes illustrated inFIG.1. More specifically, a positive z-axis direction is defined as an upward direction, and a negative z-axis direction is defined as a downward direction. A positive y-axis direction is defined and described as a forward direction, and a negative y-axis direction is defined and described as a rearward direction. A positive x-axis direction is defined as a leftward direction, and a negative x-axis direction is defined as a rightward direction.

FIGS.1and2are perspective views illustrating a steering column for a vehicle according to a first embodiment of the present invention when viewed at different angles.FIG.3is an exploded perspective view of the steering column for a vehicle illustrated inFIG.1.FIG.4is a cross-sectional view of the steering column for a vehicle illustrated inFIG.1. FIG. is an enlarged view of part ‘A’ inFIG.2.

Referring toFIGS.1to4, a steering column1for a vehicle according to a first embodiment of the present invention may include a base frame10, a housing20, a hollow shaft30, a first shaft40, a second shaft50, a roller60, and an actuator66.

Referring toFIG.1, one side of the base frame10is installed on a frame (not illustrated) of a vehicle. A plurality of holes may be formed in the base frame10, and bolts may be coupled to the plurality of holes so that the base frame10may be coupled to the vehicle frame.

Referring toFIGS.2to4, the housing20is coupled to the other side of the base frame10. The base frame10provides a space in which the housing20and the actuator66are provided in the vehicle.

The housing20includes a housing main body22, a roller coupling part26, and a transmission coupling part28. In the present embodiment, the housing main body22has a cylindrical shape having an accommodation space therein.

In this case, the housing main body22extends in one direction, i.e., a direction of a first axis C1parallel to a forward/rearward direction based onFIG.2. First and second openings221and222are famed in the direction of the first axis C1and respectively provided in front and rear portions of the housing main body22.

Referring toFIG.4, the accommodation space in the housing main body22communicates with the outside through the first and second openings221and222. The housing20accommodates the hollow shaft30, the first shaft40, and the second shaft50therein and protects the hollow shaft30, the first shaft40, and the second shaft50. In addition, the housing20provides a base on which the roller60and the actuator66are installed.

The hollow shaft30has an outer diameter equal to or somewhat smaller than an inner diameter of the housing main body22. The hollow shaft30has a predetermined length in the direction of the first axis C1. Therefore, one end of the hollow shaft30may be installed and inserted into the housing main body22through the first opening221.

In this case, the hollow shaft30is installed to be movable in the direction of the first axis C1through the first opening221of the housing main body22. In addition, the other end of the hollow shaft30protrudes to the outside of the housing main body22.

That is, at least a part of the hollow shaft30may be accommodated in an internal space of the housing main body22. Third and fourth openings31and33are respectively provided at two opposite ends of the hollow shaft30. The interior of the hollow shaft30may communicate with the outside through the third and fourth openings31and33.

The first shaft40is provided in the form of a tubular member disposed in the direction of the first axis C1and having a hollow portion. In this case, a steering wheel (not illustrated), which may be operated by a driver, may be coupled to one end of the first shaft40, i.e., a front end of the first shaft40based onFIG.3. When the driver operates the steering wheel, the first shaft40may rotate together with the steering wheel.

An outer diameter of the first shaft40is equal to or smaller than an inner diameter of the hollow shaft30. Therefore, the first shaft40may be installed in the hollow shaft30. In this case, one end of the first shaft40protrudes to the outside of the hollow shaft30.

In this case, a plurality of bearings90and92is installed between an inner peripheral portion of the hollow shaft30and an outer peripheral portion of the first shaft40. In this case, the plurality of bearings90and92include a first bearing90and a second bearing92.

In the present embodiment, the first bearing90is installed in the third opening31, the second bearing92is installed at a position adjacent to the other end of the first shaft40. In this case, the first and second bearings90and92may each be a ball bearing.

Therefore, the first shaft40may be installed in the hollow shaft30so as to be movable in the direction of the first axis C1together with the hollow shaft30while being rotatable about the first axis C1relative to the hollow shaft30.

Referring back toFIGS.3and4, the second shaft50is coupled to the other end of the first shaft40. In this case, the second shaft50is disposed in the direction of the first axis C1and disposed coaxially with the first shaft40.

An inner diameter of the first shaft40is equal to or larger than a diameter of the second shaft50. Therefore, one end of the second shaft50may be inserted into the first shaft40. In the present embodiment, the first shaft40and the second shaft50are coupled to each other by means of a spline structure so that the second shaft50may be retracted into the first shaft40or extended to the outside of the first shaft40.

More specifically, a plurality of guide grooves43is provided at the other side of an inner peripheral surface41of the first shaft40and formed in a longitudinal direction of the first shaft40. A plurality of guide protrusions52corresponding to the guide grooves43is provided on an outer peripheral surface of the second shaft50and formed in a longitudinal direction of the second shaft50.

As the second shaft50is inserted into the first shaft40in the direction of the first axis C1, the guide protrusions52and the guide grooves43may be coupled while engaging with one another. Therefore, the first shaft40and the second shaft50may rotate together about the first axis C1and move relative to each other in the direction of the first axis C1.

The driver may transmit a steering force to the first shaft40by operating the steering wheel and rotating the first shaft40about the first axis C1. The first shaft40may transmit the steering force, which is received through the steering wheel, to the second shaft50. The second shaft50may be rotated about the first axis C1by the received steering force.

Therefore, the first shaft40may transmit the steering force (steering torque) to the second shaft50. Further, the first shaft40and the second shaft50may move relative to each other in the direction of the first axis C1, such that a relative distance between the first and second shafts40and50may be adjusted. The steering column1for a vehicle according to the present embodiment may perform a telescopic function to be described below by using the above-mentioned operation.

Referring back toFIGS.3and4, one end of the second shaft50is inserted into the hollow shaft30through the fourth opening33of the hollow shaft30and then coupled to the other end of the first shaft40by means of a spline structure. In this case, the other end of the second shaft50protrudes to the outside of the hollow shaft30.

Referring toFIG.4, the hollow shaft30and the first and second shafts40and50are accommodated in the housing main body22. The hollow shaft30and the first shaft40are installed in the housing20and configured to be movable through the first opening221. In this case, one end of the hollow shaft30and one end of the first shaft40protrude to the outside of the housing main body22through the first opening221.

The other end of the second shaft50, i.e., a rear end of the second shaft50based onFIG.4protrudes to the outside through the second opening222of the housing main body22. In the present embodiment, a third bearing94may be installed in the second opening222. In this case, the third bearing93may be a ball bearing.

Therefore, the second shaft50may rotate about the first axis C1relative to the housing20. The second shaft50may be fixed so as not to relatively move in the direction of the first axis C1.

With the above-mentioned coupling relationship, the first and second shafts40and50may rotate together about the first axis C1and rotate relative to the housing20and the hollow shaft30. The first shaft40and the hollow shaft30may move in the direction of the first axis C1relative to the housing20and the second shaft50. However, the position of the second shaft50relative to the housing20is fixed in the direction of the first axis C1.

Therefore, the steering column1for a vehicle according to the first embodiment of the present invention may perform a telescopic function of adjusting a degree to which the steering wheel protrudes because the first shaft40and the hollow shaft30may relatively move in the direction of the first axis C1from the second shaft50and the housing20.

Referring toFIGS.2and5, the roller60, the actuator66, and a transmission68are provided at one side of the housing main body22, i.e., at a lower side based onFIG.2. A roller rotation shaft member64is provided at a center of the roller60.

In the present embodiment, the roller rotation shaft member64may be disposed in parallel with a second axis C2and rotate about the second axis C2. One end of the roller rotation shaft member64is rotatably coupled to the housing main body22by means of the roller coupling part26.

The transmission68is provided. The transmission68is installed at one side of the housing main body22by means of the transmission coupling part28. The other end of the roller rotation shaft member64is coupled to one side of the transmission68. The actuator rotation shaft member67, which may be rotated by the actuator66, is coupled to the other side of the transmission68. In this case, the actuator66may be configured as an electric motor.

Driving power generated by the actuator66may be transmitted to the roller60through the actuator rotation shaft member67, the transmission68, and the roller rotation shaft member64. In this case, the transmission68appropriately converts a rotational speed and a rotation angle of the actuator rotation shaft member67and transmits the driving power to the roller rotation shaft member64. Therefore, the steering column1for a vehicle according to the first embodiment of the present invention may more precisely adjust a rotational speed and a rotation angle of the roller60.

Referring toFIGS.2and5, in the present embodiment, a roller hole223is provided in a lower portion of the housing main body22and formed in the direction of the first axis C1. The roller60may press an outer peripheral portion of the hollow shaft30through the roller hole223.

In this case, the first axis C1and the second axis C2are disposed to be perpendicular to each other. Therefore, when the roller60rotates about the second axis C2, a frictional force generated between an outer peripheral surface of the roller60and the outer peripheral portion of the hollow shaft30may be applied in parallel with the direction of the first axis C1, such that the hollow shaft30and the first shaft40may be moved in the direction of the first axis C1.

As described above, according to the steering column1for a vehicle according to the first embodiment of the present invention, the telescopic means for moving the first shaft40and the hollow shaft30is simply and compactly implemented by using the roller60, the actuator66, and the transmission68. Therefore, it is possible to reduce a load applied to the housing20and the vehicle and improve the spatial utilization of the driver seat.

In addition, the steering column1for a vehicle according to the first embodiment of the present invention does not include a separate screw shaft for performing a telescopic function. Therefore, there occurs no structural defect such as bending and warping of the screw shaft.

Meanwhile, in the present embodiment, a friction member62having a high frictional coefficient is provided on the outer peripheral surface of the roller60in order to increase the frictional force between the roller60and the hollow shaft30. For example, the friction member62may be a tire having a tread formed on an outer peripheral portion thereof.

Hereinafter, a process in which the steering column1for a vehicle according to the first embodiment of the present invention performs the telescopic function will be more specifically described.

FIGS.6and7are views for explaining an operating process of the steering column for a vehicle illustrated inFIG.1, in whichFIG.6is a view illustrating a state in which the steering shaft protrudes to the outside of the housing as the roller rotates, andFIG.7is a view illustrating a state in which the steering shaft is inserted into the housing as the roller rotates.

Referring toFIG.6, the roller60according to the first embodiment of the present invention may rotate clockwise based onFIG.6while pressing the outer peripheral surface of the hollow shaft30. The frictional force generated between the roller60and the hollow shaft30may move the hollow shaft30in the direction of the first axis C1. Therefore, the first shaft may move together with the hollow shaft30in the direction of the first axis C1and protrude to the outside of the housing main body22through the first opening221.

In this case, because the second shaft50cannot move in the direction of the first axis C1relative to the housing main body22, the second shaft50is extended to the outside of the first shaft40and the hollow shaft30as the first shaft40and the hollow shaft30move in the direction of the first axis C1.

Referring toFIG.7, the roller60according to the first embodiment of the present invention may rotate counterclockwise based onFIG.7while pressing the outer peripheral surface of the hollow shaft30. The frictional force generated between the roller60and the hollow shaft30may move the hollow shaft30in a direction opposite to the direction of the first axis C1. Therefore, the first shaft40may move together with the hollow shaft30in the direction opposite to the direction of the first axis C1and be inserted into the housing main body22through the first opening221.

In this case, because the second shaft50cannot move in the direction of the first axis C1relative to the housing20, the second shaft50is retracted into the first shaft40and the hollow shaft30as the first shaft40and the hollow shaft30move in the direction opposite to the direction of the first axis C1.

As described above, the steering column1for a vehicle according to the first embodiment of the present invention adjusts the telescopic distance by using the rotation of the roller60, such that there is no limitation in the telescopic operating distance. That is, the telescopic operating distance does not depend on the length of the screw shaft.

FIG.8is a perspective view of the steering column for a vehicle illustrated inFIG.1. In this case, the base frame is not illustrated for explaining the present invention.FIG.9is an enlarged view of part ‘B’ inFIG.8. The housing, a support member, an elastic member, and a coupling member are disassembled for explaining the present invention.FIG.10is an exploded perspective view illustrating the support member, the elastic member, and the coupling member of the steering column for a vehicle illustrated inFIG.1when viewed at different angles.FIG.11is a cross-sectional view illustrating a hollow tube, the housing, the support member, the elastic member, the coupling member, and the base frame of the steering column for a vehicle illustrated inFIG.1.

Referring toFIGS.4and8, the steering column1for a vehicle according to the first embodiment of the present invention may further include support members70and80. The support members70and80are installed on the housing main body22so that one side of each of the support members70and80supports the hollow shaft30while adjoining the outer peripheral portion of the hollow shaft30. In this case, the support members70and80may be provided in plural, and the plurality of support members70and80may include a first support member70and a second support member80.

The first and second support members70and80are disposed to be opposite to the roller60based on the hollow shaft30. That is, based onFIG.4, the first and second support members70and80may be disposed above the hollow shaft30so as to be opposite to the roller60disposed below the hollow shaft30.

Therefore, the support member may provide a reaction force that presses the hollow shaft30downward against the force applied by the roller60to press the hollow shaft30upward. A vertical drag force and a frictional force may be generated between the hollow shaft30and the roller60.

Referring toFIGS.4and8, in the present embodiment, the first and second support members70and80are arranged in the axial direction of the hollow shaft30(the direction of the first axis C1). In this case, the first and second support members70and80may be respectively disposed at a front side L2and a rear side L2based on a center L1of the roller60when viewed in the direction of the first axis C1.

The first and second support members70and80are respectively disposed at the front and rear sides of the roller60and support the hollow shaft30, which makes it possible to prevent the hollow shaft30from being inclined by a force applied by the roller60to press the hollow shaft30.

Therefore, the first and second support members70and80may maintain the horizontality of the hollow shaft30. Therefore, the inner peripheral surface of the housing20and the hollow shaft30do not collide with each other, which makes it possible to prevent noise, vibration, and damage to the hollow shaft30caused by interference.

Referring toFIGS.9and10, the first support member70may include a slip bushing72, a disc spring76, and a coupling member78. The slip bushing72is configured as a member that adjoins the outer peripheral portion of the hollow shaft30and has a circular plate shape.

A coupling protrusion722is formed on one surface of the slip bushing72, i.e., an upper surface of the slip bushing72based onFIG.9. The coupling protrusion722has a predetermined thickness in an outward direction of the slip bushing72and has a circular cross-section having a smaller diameter than the slip bushing72.

Contact surfaces721are formed on the other surface of the slip bushing72, i.e., a lower surface of the slip bushing72based onFIG.10and correspond to the hollow shaft30so that the contact surfaces721may be in surface contact with the outer peripheral portion of the hollow shaft30. A center groove723is formed at a center of the contact surfaces721and disposed in a direction parallel to the axial direction of the hollow shaft30.

First and second protruding portions73and74are formed at lateral sides of the slip bushing72. In this case, the first and second protruding portions73and74face each other with the slip bushing72interposed therebetween and are disposed in the direction in which the center groove723is formed.

For example, the first and second protruding portions73and74may be respectively formed at front and rear sides of the slip bushing72based onFIG.9. The first and second protruding portions73and74extend to the outside of the slip bushing72and then are bent upward.

An elastic member may be provided at one side of the slip bushing72. In this case, the elastic member may be configured as a disc spring76. The disc spring76is coupled to the slip bushing72as the coupling protrusion722of the slip bushing72is inserted into the center hole761of the disc spring76.

The coupling member78is disposed at a side opposite to the slip bushing72based on the disc spring76. The coupling member78is provided as a cylindrical member having a predetermined thickness and one surface that adjoins the disc spring76. A first screw thread (not illustrated) may be formed on an outer peripheral surface of the coupling member78.

Referring toFIGS.9and11, in the present embodiment, a coupling hole224may be formed in the housing main body22and coupled to the first support member70. The slip bushing72is inserted into the coupling hole224so that the contact surface721adjoins the hollow shaft30, and then the disc spring76and the coupling member78are sequentially inserted and disposed into the coupling hole224.

Grooves are formed in lateral portions of the coupling hole224so that the first and second protruding portions73and74of the slip bushing72may be inserted into the grooves. Therefore, the arrangement of the slip bushing72may be adjusted so that the direction in which the center groove723of the slip bushing72is formed is parallel to the axial direction of the hollow shaft30, thereby improving the assembly properties.

A second screw thread (not illustrated) is formed on an inner peripheral surface of the coupling hole224and engages with the first screw thread. A depth by which the coupling member78is inserted into the coupling hole224may be controlled by adjusting a length of a section in which the first and second screw threads engage with each other, such that a magnitude of a force applied by the slip bushing72and the disc spring76to press the outer peripheral surface of the hollow shaft30may be adjusted.

Meanwhile, the second support member80may be identical to the first support member70, and the second support member80may be installed on the housing20by means of the same coupling structure as the first support member70. Therefore, a description thereof will be omitted.

Meanwhile, referring back toFIGS.2and3, the housing20is rotatably coupled to the base frame10by means of housing rotation shaft members24. First coupling portions12are provided at the other side of the base frame10and protrude toward the housing20while surrounding lateral portions of the housing20. In this case, the first coupling portions12are symmetrically formed with respect to the housing20.

Second coupling portions23are formed at one side of the housing main body22. The second coupling portions23extend while defining a predetermined angle with respect to the first axis C1and then extend in parallel with an extension direction of the housing main body22(the direction of the first axis C1). In this case, the second coupling portions23are symmetrically provided with respect to the first axis C1.

The housing rotation shaft members24are installed by simultaneously penetrating the first and second coupling portions12and23. In this case, the housing rotation shaft members24are arranged in parallel with a third axis C3provided to the first axis C1. Therefore, the housing20and the first shaft40installed on the housing20may pivotally rotate about the third axis C3relative to the base frame10.

In addition, the housing rotation shaft members24each have a length corresponding to a thickness of each of the first and second coupling portions12and23in the direction of the third axis C3. In this case, the housing rotation shaft members24are symmetrically provided with respect to the housing20. Therefore, there occurs no interference between the housing rotation shaft members24and the second shaft50even though the second shaft50protrudes to the outside of the housing20through the second opening222of the housing main body22.

Meanwhile, a tilting device (not illustrated) capable of pivotally rotating the housing20about the third axis C3may be provided at one side of the housing20. The tilting device may be installed in the base frame10or the vehicle.

In this case, the tilting device may be configured as a publicly-known motor and a transmission device that provide power for rotating the housing20and the first shaft40installed in the housing20. Therefore, the steering column1for a vehicle according to the first embodiment of the present invention may perform the tilting function of adjusting an angle by which the steering wheel provided at one end of the first shaft40is inclined.

Hereinafter, second and third embodiments of the present invention will be described. The steering columns for a vehicle according to the second and third embodiments of the present invention may have the same components as the steering column according to the first embodiment, except for rollers, gears, and hollow shafts. Therefore, a description of the same components will be omitted, and the rollers, the gears, and the hollow shafts according to the second and third embodiment of the present invention will be described.

FIG.12is an enlarged perspective view illustrating a part of a steering column for a vehicle according to a second embodiment of the present invention.FIG.13is a cross-sectional view illustrating a roller and a hollow shaft of a steering column for a vehicle illustrated inFIG.12. The roller and the hollow shaft are somewhat spaced apart from each other for explaining the present invention.

Referring toFIGS.12and13, a groove62′ is provided in an outer peripheral surface of a roller60′ of a steering column1′ for a vehicle according to a second embodiment of the present invention and formed in a circumferential direction of the roller60′. In this case, the groove62′ of the roller60′ has a shape corresponding to a shape of an outer peripheral portion of a hollow shaft30′.

The outer peripheral portion of the hollow shaft30′ adjoins and is seated on an inner surface61′ of the groove62′ formed in the roller60′. Therefore, an area in which the outer peripheral surface of the roller60′ and the outer peripheral portion of the hollow shaft30′ adjoin each other may increase.

Therefore, the roller60′ of the steering column1′ for a vehicle according to the second embodiment of the present invention may more stably press the outer peripheral portion of the hollow shaft30′, and driving power generated by an actuator66′ may be efficiently converted into a frictional force that may move the hollow shaft30′ in the axial direction.

Meanwhile, a friction member (not illustrated) having a high frictional coefficient may be provided inside the groove62′ of the roller60′ according to the second embodiment of the present invention. The friction member may increase a frictional force between the roller60′ and the hollow shaft30′.

FIG.14is a perspective view of a steering column for a vehicle according to a third embodiment of the present invention.FIG.15is a cross-sectional view illustrating a hollow shaft and first and second gears of the steering column for a vehicle illustrated inFIG.14.

Referring toFIGS.14and15, a steering column1″ for a vehicle according to a third embodiment of the present invention may include a first gear32″ and a second gear60″. In this case, the first and second gears32″ and60″ may each be configured as a publicly-known gear member. For example, the first gear32″ may be a rack gear, and the second gear60″ may be a spur gear.

The first gear32″ is provided on an outer peripheral portion of a hollow shaft30″ and formed in an axial direction of the hollow shaft30″. Of course, the first gear32″ may be formed in a direction different from the axial direction of the hollow shaft30″ so that the hollow shaft30″ may move in the direction different from the axial direction.

In this case, in the present embodiment, the first gear32″ is provided at one side portion of the hollow shaft30″, i.e., a lower portion of the hollow shaft30″ based onFIG.14. A gear hole223″ is formed in a housing20″, provided in the axial direction of the hollow shaft30″, and disposed at a position corresponding to the first gear32″.

The second gear60″ is disposed at one side of the hollow shaft30″ and one side of the housing20″. In this case, the second gear60″ may be coupled to the first gear32″ of the hollow shaft30″ through the gear hole223″ of the housing20″. A gear shaft64″ is formed at a center of the second gear60″. The gear shaft64″ is disposed in a direction perpendicular to the hollow shaft30″.

The transmission68″ is provided. The transmission68″ may be installed at one side of the housing20″. The gear shaft64″ may be coupled to one side of the transmission68″, and an actuator66″ may be coupled to the other side of the transmission68″.

The actuator66″ may generate driving power and rotate the second gear60″ through the transmission68″ and the gear shaft64″. When the second gear60″ is rotated in one direction by the actuator66″, the first gear32″ engaging with the second gear60″ may receive a force in the axial direction of the hollow shaft30″ or a direction opposite to the axial direction.

That is, the second gear60″ may transmit the driving power, which is generated by the actuator66″, to the hollow shaft30″ through the first gear32″. Therefore, the first gear32″, the hollow shaft30″, and a first shaft40″ may move to the inside or outside of the housing20″ through a first opening221″.

As described above, according to the steering column for a vehicle according to the embodiment of the present invention, the first shaft to which the steering wheel is coupled is movable in the axial direction together with the hollow shaft, such that the telescopic function of adjusting a degree to which the steering wheel protrudes may be performed.

In addition, according to the steering column for a vehicle according to the embodiment of the present invention, the roller or gear configured to rotate about the axis performs the telescopic function by moving the hollow shaft and the first shaft in the axial direction. Therefore, it is possible to perform the telescopic function without limitation in operating distance.

In addition, according to the steering column for a vehicle according to the embodiment of the present invention, the telescopic function is performed by the simple and compact configuration using the rotation of the roller or gear, and the screw shaft in the related art is not required. Therefore, it is possible to reduce the number of required components and the manufacturing costs, minimize the likelihood of the occurrence of a structural defect such as bending of the shaft, and improve the spatial utilization of the driver seat.

While the embodiments of the present invention have been described above, the spirit of the present invention is not limited to the embodiments presented in the present specification, those skilled in the art, who understand the spirit of the present invention, may easily propose other embodiments by adding, changing, deleting constituent elements within the same spirit and scope of the present invention, and it can be said that the embodiments are also within the spirit and scope of the present invention.

DESCRIPTION OF REFERENCE NUMERALS

1: Steering column for a vehicle10: Base frame20: Housing30: Hollow shaft40: First shaft50: Second shaft60: Roller70: First support member80: Second support member90,92,94: Bearing