Steering column

Disclosed herein is a steering column including a mounting bracket, a housing rotated in upward and downward directions relative to the mounting bracket, an inner tube installed in a hollow of the housing so as to be axially extensible and contractible, an operating lever installed to the mounting bracket and an adjustment bolt passing through the housing so as to be tightened and released, a telescopic assembly including a fixed gear installed on the inner tube and a movable gear engaged with the fixed gear depending on axial movement of the adjustment bolt, and a bending plate provided between the inner tube and the fixed gear.

CROSS REFERENCE TO PRIOR APPLICATIONS

This application is a National Stage Patent Application of PCT International Patent Application No. PCT/KR2015/004275 (filed on Apr. 28, 2015) under 35 U.S.C. § 371, which claims priority to Korean Patent Application Nos. 10-2014-0050509 (filed on Apr. 28, 2014) and 10-2015-0054748 (filed on Apr. 17, 2015), which are all hereby incorporated by reference in their entirety.

TECHNICAL FIELD

The present invention relates to a steering column, and more particularly, to a steering column having the same energy absorption characteristics for each tele-position. In addition, the present invention relates to a steering column having an improved telescopic structure such that the movement of the steering column can be controlled in a tele-direction by engagement of a fixed gear with a movable gear of a fixing unit, which rectilinearly moves, when an operating lever is operated.

BACKGROUND ART

In general, a steering column is a device which surrounds and rotatably supports a steering shaft for transferring torque, generated by operating a steering wheel by a driver, to a rack-pinion mechanism while being coupled to a vehicle body through a bracket to fix the position of the steering shaft.

The steering column may have a telescopic or tilt function for the convenience of drivers. The tilt function serves to adjust the fixed angle of the steering wheel. The telescopic function allows two hollow pipes to be axially extensible and contractible by inserting the hollow pipes into the steering column, and also serves to absorb impact energy through the collapse of the steering shaft and the steering column in the event of collision of vehicles.

Accordingly, the steering column is classified into a telescopic steering column and a tilt steering column depending on the function thereof. In some cases, a tilt function may also be added to the telescopic steering column. Through such a tilt function, a driver may smoothly operate the steering wheel by adjusting the protruding or tilt angle of the steering wheel so as to be suitable for his/her height or body.

The telescopic or tilt operation of the steering column is typically performed by pressing a housing or releasing the pressing thereof according to tightening or releasing an operating lever.

In particular, the telescopic operation of the steering column is mostly performed by pressing the housing or releasing the pressing thereof.

Representative examples of steering columns are illustrated inFIGS. 1 and 2, and conventional steering columns will be described in brief with reference toFIGS. 1 and 2.

As illustrated inFIG. 1, the steering column according to the related art1includes a mounting bracket10installed in a vehicle, a housing20installed in the mounting bracket10, and an operating lever30for pressing the tilt bracket10and the housing20or releasing the pressing thereof.

In addition, the housing20is formed with a slit21for pressing an inner tube40, and a telescopic guide22through which an adjustment bolt31of the operating lever30slides.

However, in the steering column of the related art1, the deformation of the housing20varies due to the slit21and the telescopic guide22, which may lead to a variation in fixing force of the operating lever30.

In addition, the adjustment bolt31must be moved to the tele-in position (the right inFIG. 1) of the telescopic guide22in order to absorb impact energy through the collapse of the steering column in the event of collision of a vehicle. Hence, the steering column has different energy absorption characteristics for each tele-position.

As illustrated inFIG. 2, the steering column according to the related art2includes a tilt bracket10′ installed in a vehicle, a housing20′ installed in the tilt bracket10′, an operating lever30′ for pressing the tilt bracket10′ and the housing20′ or releasing the pressing thereof, and an inner tube40′ inserted into the hollow of the housing20′.

In addition, the inner tube40′ is formed with a telescopic guide41′ through which an adjustment bolt31′ of the operating lever30′ slides.

In the steering column of the related art2, the housing20′ is fixed, and thus no variation in operating force of the operating lever30′ occurs.

However, even in the steering column of the related art2, the adjustment bolt31′ must be moved to the tele-in position (the right inFIG. 2) of the telescopic guide41′ in order to absorb impact energy through the collapse of the steering column in the event of collision of a vehicle. Hence, the steering column has different energy absorption characteristics for each tele-position.

Accordingly, it is necessary to develop a steering column having the same energy absorption characteristics for each tele-position while an operating lever has the same operating force for each tele-position.

DISCLOSURE

Technical Problem

Accordingly, the present invention has been made in view of the above-mentioned problems, and an object thereof is to provide a steering column which has the same energy absorption characteristics for each tele-position while an operating lever has the same operating force for each tele-position, and the movement of which can be controlled in a tele-direction by engagement of a fixed gear with a movable gear when the operating lever is operated while the steering column has the reduced number of parts and a reduced weight.

Technical Solution

In accordance with an aspect of the present invention, a steering column includes a mounting bracket, a housing rotated in upward and downward directions relative to the mounting bracket, an inner tube installed in a hollow of the housing so as to be axially extensible and contractible, an operating lever installed to the mounting bracket and an adjustment bolt passing through the housing so as to be tightened and released, a telescopic assembly including a fixed gear installed on the inner tube and a movable gear engaged with the fixed gear depending on axial movement of the adjustment bolt, and a bending plate provided between the inner tube and the fixed gear.

The bending plate may be rolled and inserted into the fixed gear when the inner tube is axially contracted relative to the housing.

The inner tube may be fastened to the fixed gear by a rivet, and the rivet may be destroyed when a load, which is equal to or greater than a predetermined value, is axially applied to the inner tube.

The fixed gear may have a receiving groove into which the bending plate is inserted, and the bending plate may have a restraint end fixed to the inner tube while being inserted into the receiving groove, and a free end exposed to the outside of the fixed gear.

The fixed gear may have a guide member for guiding the bending plate into the receiving groove.

The bending plate may have a “U”-bent shape.

The steering column may further include a tilting assembly coupled to both sides of the inner tube, and rotating the housing in the upward and downward directions relative to the mounting bracket when the operating lever is operated, and a fixing unit mounted to the other side of the adjustment bolt, the fixing unit being rectilinearly moved depending on operation of the operating lever so that the movable gear is engaged with or disengaged from the fixed gear, thereby fixing or releasing the tilting assembly.

The housing may have a right coupling part, a portion of which has a bush mounting hole and a spring support hole formed therein being disposed at an upper portion of the fixed gear while protruding inward from the right coupling part, and a gear guide part may be formed outside the spring support hole in a stepped manner so as to rectilinearly move the movable gear.

The gear guide part may be cut and formed so as to support a portion of an upper portion of and an entire lower portion of the movable gear.

The fixing unit may include a fixing bush mounted to the adjustment bolt while being located at a right coupling part of the housing, a spring mounted to the adjustment bolt while being located outside the fixing bush, a bush tube mounted to the adjustment bolt while being located outside the movable gear located outside the spring, and a washer and a nut coupled to the adjustment bolt while being located outside the bush tube.

The movable gear may have a spring support part and a tube support part formed in a stepped manner at both sides thereof on the basis of a shaft through-hole through which the adjustment bolt passes, and the movable gear may have a gear coupling part elongated and formed at a lower portion thereof, the gear coupling part being engaged with or disengaged from the fixed gear.

The gear coupling part may have the same width as the tube support part so as to be smoothly engaged with or disengaged from the fixed gear formed on the inner tube.

Advantageous Effects

In accordance with a steering column of the present invention, no variation in operating force of an operating lever for each tele-position can occur by engagement of a fixed gear with a movable gear. That is, the usability of the operating lever can be consistently maintained by minimizing the variation in operating force of the operating lever, thereby improving the emotional quality of product.

In addition, when an impact is axially applied to an inner tube, an energy absorption function is immediately activated by the engagement of the fixed gear with the movable gear and thus the steering column can have the same energy absorption characteristics for each tele-position. This is because the collapse is performed in the state in which the inner tube is not moved to a tele-in position by the engagement of the fixed gear with the movable gear in the present invention, unlike the conventional technique that absorbs energy after an inner tube forcibly slides to a tele-in position.

In addition, since the movable gear is engaged with the fixed gear while rectilinearly moving by the tension of a spring when the operating lever is operated, it is possible to prevent the variation in operating force of the operating lever from occurring for each tele-position.

In addition, when an impact is axially applied to a bush tube, the energy absorption function is immediately activated by the engagement of the fixed gear with the movable gear and thus the steering column can have the same energy absorption characteristics for each tele-position.

In addition, since the spring is supported by the housing and the movable gear when the spring is operated depending on the operation of the operating lever, it is possible to prevent unstable movement and occurrence of noise.

In addition, the rotation of the movable gear can be prevented owing to moment by the tension of the spring when the operating lever is operated, by increasing the connection overlap between the movable gear and the bush tube, thereby preventing the movable gear from unstably engaging with the fixed gear.

BEST MODE FOR INVENTION

Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings.

FIG. 3is a perspective view illustrating a steering column according to an embodiment of the present invention.FIG. 4is a perspective view illustrating a state in which a mounting bracket is removed from the steering column ofFIG. 3.FIG. 5is an exploded perspective view illustrating a telescopic assembly ofFIG. 4.FIGS. 6 to 8are perspective views illustrating the operation of the telescopic assembly.

As illustrated inFIGS. 3 to 8, the steering column, which is designated by reference numeral A, according to the embodiment of the present invention includes a mounting bracket100which is fixedly attached to a vehicle, a housing200which is installed in the mounting bracket100to rotate relative to the mounting bracket100, an inner tube300which is installed in the hollow of the housing200to be axially extensible and contractible and has a hollow shape so as to surround a steering shaft310, and an operating lever400which is installed to the mounting bracket100and an adjustment bolt410passing through the housing200so that the steering column A is telescoped or tilted by tightening and releasing the operating lever400.

In addition, the steering column A further includes a tilting assembly500which is provided between the mounting bracket100and the housing200so as to adjust the tilting of the housing200. The tilting assembly500adjusts the tilting of the steering column by engagement of a fixed gear with a movable gear.

The adjustment bolt410connected to the operating lever400is fixed through the tilting assembly500by a nut420. Meanwhile, the operating lever400and the adjustment bolt410are equipped with a driving cam and a driven cam, on which ridge and valley portions are repeatedly formed. Thus, the adjustment bolt410is longitudinally and linearly moved by the rotation of the operating lever400, thereby tightening and releasing the tilting assembly500and a telescopic assembly600to be described later.

In addition, a return spring110is installed between the mounting bracket100and the housing200.

The steering column A further includes a telescopic assembly600which fixes or releases the axial movement of the inner tube300depending on the axial movement of the adjustment bolt410.

Sine the other components of the steering column may adopt conventionally known components, a detailed description thereof will be omitted.

Hereinafter, the telescopic assembly600according to the embodiment of the present invention will be described.

The telescopic assembly600includes a fixed gear610which is installed on the outer peripheral surface of the inner tube300, and a movable gear620which is fixed on the adjustment bolt410and is engaged with the fixed gear610.

Thus, no variation in operating force of the operating lever400for each tele-position may occur by the engagement of the fixed gear610with the movable gear620.

This is because the fixed gear610engages with the movable gear620by the operation of the operating lever400and the steering column A is thus adjusted in a telescopic manner in the present invention, unlike the conventional technique that presses or releases a target to be fixed using an operating lever.

That is, the usability of the operating lever400is consistently maintained by minimizing the variation in operating force of the operating lever400, thereby improving the emotional quality of product.

In addition, the steering column A further includes a bending plate630which is provided between the inner tube300and the fixed gear610. The bending plate630is rolled and inserted into the fixed gear610when the inner tube300is axially contracted relative to the housing200.

Thus, the bending plate630functions to absorb impact energy while collapsing.

The inner tube300is fastened to the fixed gear610by a rivet611, and the rivet611is configured to be destroyed when a load, which is equal to or greater than a predetermined value, is axially applied to the inner tube300. The rivet611may have a “V”-shaped cutting groove so as to be cut under a predetermined load or more, or may be made of a material in which the rivet itself is broken under a predetermined load.

Meanwhile, the fixed gear610has a receiving groove612into which the bending plate630is inserted. The bending plate630has a restraint end631which is inserted into the receiving groove612and is fixed to the inner tube300and a free end632which is exposed to the outside of the fixed gear610. The restraint end631of the bending plate630is fixed to the inner tube300by welding or mechanism means.

In addition, the fixed gear610further has a guide member613which guides the bending plate630into the receiving groove612so that the bending plate630is rolled and inserted into the receiving groove612.

The bending plate630has a “U”-bent shape, and is rolled and inserted into the receiving groove612.

Accordingly, when an impact is axially applied to the inner tube300, a collapse function (an energy absorption function) is immediately activated by the engagement of the fixed gear610with the movable gear620and thus the steering column has the same energy absorption characteristics for each tele-position.

This is because the collapse is performed in the state in which the inner tube300is not moved to a tele-in position by the engagement of the fixed gear610with the movable gear620in the present invention, unlike the conventional technique that absorbs energy after an inner tube forcibly slides to a tele-in position.

In this case, the energy generated by the contraction of the inner tube300due to an axial impact applied thereto is absorbed while the bending plate630is rolled and inserted into the receiving groove612by the guide member613, as illustrated inFIGS. 7 and 8.

Meanwhile, a steering column A according to another embodiment of the present invention may further include a fixing unit700which rectilinearly moves depending on the operation of an operating lever400and operates or stops a tilting assembly500, such that a movable gear620is engaged with or disengaged from a fixed gear610. A description thereof will be given later in detail with reference to the drawings.

FIG. 9is an assembled perspective view illustrating a steering column according to another embodiment of the present invention.FIG. 10is an exploded perspective view of the steering column illustrated inFIG. 9.FIG. 11is a partially expanded perspective view illustrating a housing constituting the steering column illustrated inFIG. 9.FIG. 12is a perspective view illustrating a movable gear of the steering column illustrated inFIG. 9.FIG. 13is a front view illustrating a state in which a fixed gear is disengaged from a fixing unit when an operating lever constituting the steering column illustrated inFIG. 9is operated.FIG. 14is an expanded view illustrating a main portion ofFIG. 13.FIG. 15is a front view illustrating a state in which the fixed gear is fixed to the fixing unit when the operating lever constituting the steering column illustrated inFIG. 9is operated.FIG. 16is an expanded view illustrating a main portion ofFIG. 15.

Referring toFIGS. 9 to 15, the steering column, which is designated by reference numeral A, according to another embodiment of the present invention includes a mounting bracket100, a tilting assembly500, an adjustment bolt410, a fixed gear610, a movable gear620, a fixing unit700, etc.

The mounting bracket100fixes a housing200, which has an inner tube300seated therein, to one side of a vehicle. The mounting bracket100has a predetermined thickness and width, and has a plurality of coupling holes which are formed at intervals therein for coupling and fixing.

Here, the mounting bracket100is arranged perpendicular to the housing200having the inner tube300seated therein so as to stably fix the housing200to one side of the vehicle.

In addition, the housing200has a predetermined size, and has a mounting space200aformed therein for receiving the inner tube300. The housing200has left and right coupling parts200band200cwhich are respectively formed at both sides thereof.

That is, the inner tube300may be received in the mounting space200aof the housing200, the adjustment bolt410may be supported by the housing200while passing through the left and right coupling parts200band200c, and the fixed gear610, the movable gear620, and the fixing unit700may be arranged in the right coupling part220c.

In the right coupling part200cof the housing200, a portion, in which a bush mounting hole200c-1and a spring support hole200c-2are formed, is disposed at the upper portion of the fixed gear610while protruding inward from the right coupling part200c, and a gear guide part200c-3is formed outside the spring support hole200c-2in a stepped manner so as to rectilinearly move the movable gear620.

In more detail, the right coupling part200cfixes a fixing bush710of the fixing unit700, which is mounted to the adjustment bolt410passing through the tilting assembly500, through the bush mounting hole200c-1, and allows a spring720and the movable gear620to be rectilinearly moved through the spring support hole200c-2and the gear guide part200c-3. Consequently, it is possible to prevent the spring720and the movable gear620from unstably moving and to prevent noise from occurring.

Here, since the bush mounting hole200c-1and the spring support hole200c-2are located inside the fixed gear610, it is possible to prevent the fixing unit700from unstably operating while rectilinearly moving.

The gear guide part200c-3is cut and formed so as to support a portion of the upper portion of and the entire lower portion of the movable gear620.

That is, the gear guide part200c-3is partially cut such that the movable gear620is not deviated from the eccentricity thereof while rectilinearly moving, thereby enabling the movable gear620to be accurately operated while the weight of the gear guide part is reduced.

In more detail, the gear guide part200c-3guides the entire upper portion of and a portion of the lower portion of the movable gear620when the fixed gear610engages with the movable gear620. The gear guide part200c-3guides a half of the upper portion of and the entire lower portion of the movable gear620when the fixed gear is disengaged from the movable gear620.

Meanwhile, the tilting assembly500is coupled to both sides of the inner tube300, and rotates the housing200in the upward and downward directions relative to the mounting bracket100when the operating lever400is operated.

That is, the tilting assembly500is coupled to both sides of the inner tube300so as to be moved relative to the mounting bracket100in order to reduce a handle pushing force applied by a driver according to the degree of impact in the event of collision of the vehicle.

The tilting assembly500rotates about the adjustment bolt410depending on the operation of the operating lever400coupled to the adjustment bolt410.

The operating lever400may be installed to the left or right of the tilting assembly500. Here, the case where the operating lever400is installed to the left of the tilting assembly500will be described.

One side of the adjustment bolt410is coupled to the operating lever400, and the other side thereof passes through the left and right coupling parts200band200cconstituting the housing200.

That is, the adjustment bolt410has a predetermined diameter and length. One end of the adjustment bolt410is coupled to the operating lever400, and the other end thereof is coupled to the fixing unit700through the housing200. The adjustment bolt410serves to rectilinearly move the fixing unit700depending on the operation of the operating lever400.

The fixed gear610is coupled to the inner tube300in the same line as the right coupling part200cof the housing200.

That is, the fixed gear610is longitudinally mounted to the inner tube300, and is engaged with or disengaged from the movable gear620which is operated along with the operation of the operating lever400.

Meanwhile, the fixing unit700is mounted to the other side of the adjustment bolt410, and is rectilinearly moved depending on the operation of the operating lever400. The fixing unit700may operate or stop the tilting assembly500in such a manner that the movable gear620is engaged with or disengaged from the fixed gear610.

The fixing unit700includes a fixing bush710which is located at the right coupling part200cof the housing200and is mounted to the adjustment bolt410, a spring720which is located outside the fixing bush710and is mounted to the adjustment bolt410, a bush tube730which is located outside the movable gear620located outside the spring720and is mounted to the adjustment bolt410, and a washer740and a nut750which are located outside the bush tube730and are coupled to the adjustment bolt410. Here, the movable gear620is located between the spring720and the bush tube730and is mounted to the adjustment bolt410.

Although the movable gear620has been described to be one of the components of the telescopic assembly in the embodiment illustrated inFIGS. 1 to 8, the movable gear620may be described to be one of the components of the fixing unit700in another embodiment illustrated inFIGS. 9 to 15.

As described above, the fixing bush710, the spring720, the movable gear620, the bush tube730, the washer740, and the nut750are sequentially mounted to the adjustment bolt410, so that the fixing unit700may be rectilinearly moved depending on the operation of the operating lever400.

In more detail, in the fixing unit700, when the operating lever400is operated, the movable gear620, the bush tube730, the washer740, and the nut750compress the spring720while moving in the right direction, and the movable gear620is engaged with the fixed gear610. When the operating lever400is released, the movable gear620, the bush tube730, the washer740, and the nut750are moved in the left direction by the elasticity of the operating lever400and the spring720, and the movable gear620is disengaged from the fixed gear610.

The movable gear620has a spring support part620band a tube support part620cwhich are formed in a stepped manner at both sides thereof on the basis of a shaft through-hole620athrough which the adjustment bolt410passes. The movable gear620has a gear coupling part620dwhich is elongated and formed at the lower portion thereof, and the gear coupling part620dis engaged with or disengaged from the fixed gear610.

Here, the gear coupling part620dhas the same width as the tube support part620cso as to be smoothly engaged with or disengaged from the fixed gear610formed on the inner tube300.

That is, the rotation of the movable gear620is prevented owing to moment by the tension of the spring720when the operating lever400is operated, by increasing the connection overlap between the movable gear620and the bush tube730, thereby preventing the movable gear620from unstably engaging with the fixed gear610.

In addition, the bush tube730has a predetermined diameter and length, and serves to rectilinearly move the movable gear620when the operating lever400is operated.

That is, the bush tube730is rectilinearly moved together with the movable gear620by the tension of the spring720, and enables the movable gear620to be engaged with or disengaged from the fixed gear610.

In addition, the washer740and the nut750are coupled to the end of the adjustment bolt410so as to fix and support the fixing unit700. In this case, the washer740and the nut750may be a washer and a nut which are known.

Since the steering column includes the fixing unit700having the above configuration, the movable gear620is engaged with the fixed gear610while rectilinearly moving by the tension of the spring720when the operating lever400is operated. Therefore, it is possible to prevent the variation in operating force of the operating lever from occurring for each tele-position. In addition, when an impact is axially applied to the bush tube730, an energy absorption function is immediately activated by the engagement of the fixed gear610with the movable gear620and thus the steering column may have the same energy absorption characteristics for each tele-position.

The configuration and assembly sequence of the steering column according to another embodiment will be described in more detail.

First, after forming the housing200which has a predetermined size, has the mounting space200aformed therein for receiving the inner tube300, and has the left and right coupling parts200band200crespectively formed at both sides thereof, the inner tube300, to which the fixed gear610is longitudinally mounted in the same line as the right coupling part200c, is mounted in the mounting space200aof the housing200.

The mounting bracket100, which has a predetermined thickness and width and has the coupling holes formed at intervals therein for coupling and fixing, is mounted to the upper portion of the housing200, having the inner tube300seated therein, in the direction perpendicular to the housing200.

Next, the tilting assembly500, which rotates the housing200in the upward and downward directions relative to the mounting bracket100when the operating lever400is operated, is mounted to both sides of the inner tube300.

After the operating lever400is disposed to the left of the tilting assembly500, one side of the adjustment bolt410having a predetermined diameter and length is coupled to the operating lever400, and the other side thereof passes through the housing200.

Next, the assembly of the steering column A is completed by mounting the fixing unit700to the other side of the adjustment bolt410, the fixing unit700including the fixing bush710which is located at the right coupling part200cof the housing200and is mounted to the adjustment bolt410, the spring720which is located outside the fixing bush710and is mounted to the adjustment bolt410, the movable gear620which is mounted to the adjustment bolt410while being located outside the spring720and has gear teeth formed on the lower inner surface thereof, the bush tube730which is located outside the movable gear620and is mounted to the adjustment bolt410, and the washer740and the nut750which are located outside the bush tube730and are coupled to the adjustment bolt410.

Here, the assembly sequence of the steering column may also differ from that described above.

Hereinafter, the usage of the steering column having the above configuration will be described.

Referring toFIGS. 13 and 14, first, when the user operates the operating lever400such that the steering column tilts up and down, the adjustment bolt410connected to the operating lever400is moved in the left direction, and the movable gear620, the bush tube730, the washer740, and the nut750, which constitute the fixing unit700, are rectilinearly moved in the left direction by the elasticity of the operating lever400and the spring720, with the consequence that the movable gear620is disengaged from the fixed gear610.

Referring toFIGS. 15 and 16, when the user operates the operating lever400after the steering column tilts up and down to a desired position, the adjustment bolt410connected to the operating lever400is moved in the right direction, and the movable gear620, the bush tube730, the washer740, and the nut750, which constitute the fixing unit700, compress the spring720while rectilinearly moving in the right direction, with the consequence that the movable gear620is engaged with the fixed gear610so that the steering column is maintained in the state in which it tilts up and down.

Although the present invention has been described with respect to the illustrative embodiments, it will be apparent to those skilled in the art that various variations and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.

INDUSTRIAL APPLICABILITY

In accordance with the present invention, the usability of an operating lever can be consistently maintained by minimizing a variation in operating force of the operating lever, thereby improving the emotional quality of product. It is possible to a steering column having the same energy absorption characteristics for each tele-position since an energy absorption function is immediately activated by engagement of a fixed gear with a movable gear when an impact is axially applied to an inner tube.