STEERING DEVICE

A steering device comprises a tilt-telescopic mechanism to switch between its tilt-and-axial move allowed state and its prohibited state. The tilt-telescopic mechanism comprises a pair of side wall portions provided on both sides, in a vehicle width direction, of an upper column, a bolt penetrating the side wall portions and pressing the side wall portions against each other in an approaching direction, a lever, and a biasing portion arranged between each of the side wall portions and the upper column and operative to apply a pressing force to the upper column from the both sides, in the vehicle width direction, thereof. The biasing portion comprises a pair of upper-side pressing portions to press an upper portion of the upper column above its axial center from both sides and a pair of lower-side pressing portions to press a lower portion of that below its axial center from both sides.

BACKGROUND OF THE INVENTION

The present invention relates to a steering device in which a steering shaft is expandable and tiltable.

Conventionally, various types of steering device for a vehicle in which the expandable and tiltable steering shaft can be fixed at a desired length and angle has been proposed.

The steering device disclosed in Japanese Patent Laid-Open publication No. H11-278283 comprises a cylindrical support column to support the expandable steering shaft, which is comprised of an upper jacket and a lower jacket which are engaged with each other, a support bracket with a pair of side wall portions to support the upper and lower jackets at a vehicle body in a tiltable manner, and a reinforcement bracket arranged between each of the pair of side wall portions and the upper and lower jackets so as to press the upper and lower jackets from both sides, in a vehicle width direction, thereof by a fastening force of a bolt.

The reinforcement bracket is a roughly U-shaped plate member to cover a lower half of the upper and lower jackets and has a pair of pressing portions facing to each other.

In a state where the bolt is fastened, the fastening force of the bolt makes a distance between the pair of pressing portions of the reinforcement narrower, thereby pressing the lower half of the upper and lower jackets engaged with each other toward an inward side from an outward side, in the vehicle width direction, thereof, so that the upper and lower jackets can be fixed at the desired length and angle.

In the above-described steering device, while the pair of pressing portions with the narrowed distance caused by the fastening force of the bolt press the lower half of the upper and lower jackets engaged with each other (support column) toward the inward side from the outward side, in the vehicle width direction, thereof, an upper half of the upper and lower jackets does not receive any pressing force. Accordingly, it is difficult to increase the fastening rigidity in the event of fastening the upper and lower jackets.

Further, since the above-described structure requires that a strong pressing force is applied only to the lower half of the upper and lower jackets and thereby a whole part of the upper and lower jackets is fixed, it may be unavoidable to increase the fastening force of the bolt. Therefore, there is a concern that improperly long time may be required to release the bolt's fastening completely in the event of releasing the bolt's fastening and also in a case where the fastening force of the bolt is not released sufficiently, the tilting and axial moving of the upper and lower jackets may not be conducted smoothly.

SUMMARY OF THE INVENTION

The present invention has been devised in view of the above-described matter, and an object of the present invention is to provide a steering device which can properly fix a steering column supporting a steering shaft at the high fastening rigidity and conduct the tilting and axial moving of a steering column smoothly in the event of releasing the bolt's fastening.

The steering device of the present invention comprises an upper shaft extending in a vehicle longitudinal direction and having a rear end portion to which a steering wheel is fixed, an upper column rotatably supporting the upper shaft, a lower shaft connected to a front end portion of the upper shaft so as to slide in an axial direction, a lower column rotatably supporting the lower shaft and provided to be movable in an axial direction relative to the upper column, a support bracket fixed to a vehicle body and supporting a support-side column which is either one of the lower column and the upper column, and a tilt-telescopic mechanism operative to switch a state of the support-side column between a movable state where the support-side column is allowed to tilt in a vertical direction and move in an axial direction and a prohibited state where the support-side column's tilting and moving is prohibited, wherein the tilt-telescopic mechanism includes a pair of side wall portions provided at the support bracket to interpose the support-side column therebetween from both sides in a vehicle width direction and having tilting long holes extending in the vertical direction, a bolt penetrating the pair of side wall portions through the tilting long holes and producing a fastening force to press the pair of side wall portions against each other in an approaching direction, a bolt operational portion operative to change the fasting force by rotationally operating the bolt, and a biasing member arranged between each of the pair of side wall portions and the support-side column and operative to apply a pressing force to the support-side column from the both sides, in the vehicle width direction, thereof when the pair of side wall portions receive the fastening force, and the biasing member comprises at least a pair of upper-side pressing portions provided to press a portion of the support-side column which is above an axial center of the support-side column from the both sides, in the vehicle width direction, thereof and at least a pair of lower-side pressing portions provided to press another portion of the support-side column which is below the axial center of the support-side column from the both sides, in the vehicle width direction, thereof.

In the above-described steering device, either one of the upper column and the lower column is supported at the support bracket as the support-side column, and the state of the support-side column is switched, by the tilt-telescopic mechanism, between the movable state where the support-side column is allowed to tilt in the vertical direction and move in the axial direction and the prohibited state where the support-side column's tilting and moving is prohibited. The tilt-telescopic mechanism comprises the biasing member which is arranged between each of the pair of side wall portions of the support bracket and the support-side column so as to apply the pressing force to the support-side column from the both sides, in the vehicle width direction, thereof when the pair of side wall portions receive the fastening force.

The above-described biasing member comprises at least the pair of upper-side pressing portions pressing the portion of the support-side column which is above its axial center from the both sides, in the vehicle width direction, thereof and at least the pair of lower-side pressing portions pressing another portion of the support-side column which is below its axial center from the both sides, in the vehicle width direction, thereof.

Accordingly, when the pair of side wall portions of the tilt-telescopic mechanism receive the fastening force of the bolt, since upper-and-lower both sides of the axial center of the support-side column are pressed from the both sides, in the vehicle width direction, thereof by the pair of upper-side pressing portions and the pair of lower-side pressing portion of the biasing member, the support-side column comes to be restrained at four separated points, in a peripheral direction, thereof in its axial-direction view. Consequently, the support-side column can be fixed at the properly-high fastening rigidity between the pair of the side wall portions.

Meanwhile, in the releasing state where the pair of side wall portions do not receive the fastening force, the upper-and-lower both sides of the axial center of the support-side column do not receive any pressing force from the biasing member. Consequently, the vertical tilting and axial moving of the support-side column can be conducted smoothly.

In the above-described steering device, it is preferable that the bolt operational portion be a lever operative to change the fastening force of the bolt inserted into the tilting long holes, this lever comprise a root-side end portion connected to the bolt and an operational-side end portion positioned on a vehicle rearward side of the bolt and operative to receive an operational force from outside, and the pair of upper-side pressing portions and the pair of lower-side pressing portions be arranged on the vehicle rearward side of the tilting long holes.

According to this structure, since the pair of upper-side pressing portions and the pair of lower-side pressing portions of the biasing member are arranged on the vehicle rearward side of a position of the bolt inserted into the tilting long holes, a position of a connection portion where the root-side end portion of the lever (the bolt operational portion) is connected to the bolt can be shifted toward a vehicle forward side from a position of the upper-side pressing portion and the lower-side pressing portion which fix the support-side column. Thereby, the length of the lever can be properly long without changing a longitudinal position of the operational-side end portion of the lever. Accordingly, the fastening force of the bolt can be properly large without increasing the operational force applied to the operational-side end portion. Consequently, the operability of the lever can improve.

In the above-described steering device, it is preferable that the pair of upper-side pressing portions and the pair of lower-side pressing portions be arranged on forward-and-rearward both sides, in the vehicle longitudinal direction, of the tilting long holes, respectively.

According to this structure, the pair of upper-side pressing portions and the pair of lower-side pressing portions of the biasing member are respectively arranged at two separated points, in the longitudinal direction, thereof in such a manner they enclose the tilting long holes formed at the side wall portions in a vehicle-width-direction view. Therefore, the pair of side wall portions can stably fix the support-side column by supporting at the front-and-rear two points of the upper-side pressing portion and the front-and-rear two points of the lower-side pressing portion which enclose the tilting long holes in the vehicle-width-direction view, i.e., at a total of four points of the pressing portions.

In the above-described steering device, it is preferable that the steering device further comprise a pair of pressing plates arranged on respective outward sides, in the vehicle width direction, of the pair of side wall portions and operative to press the pair of side wall portions to respective inward sides, in the vehicle width direction, thereof when receiving the fastening force of the bolt, and the pair of pressing plates have respective convex portions which protrude toward the side wall portions at respective positions which face the pair of upper-side pressing portions and the pair of lower-side pressing portions, interposing the side wall portions therebetween.

According to this structure, when the pressing plates receive the fastening force of the bolt, the convex portions can press the upper-side pressing portions and the lower-side pressing portions of the biasing member via the side wall portions. Thereby, the fastening force of the bolt can be effectively transmitted to the upper-side pressing portions and the lower-side pressing portions of the biasing member. As a result, the support-side column pressed by the pair of upper-side pressing portions and the pair of lower-side pressing portions of the biasing member can be stably fixed between the pair of side wall portions.

In the above-described steering device, it is preferable that the support bracket further comprise a support-bracket connection portion to interconnect the pair of side wall portions, and the support-bracket connection portion have a bending deformation portion operative to be bending-deformed in a direction where the pair of side wall portions approach each other when the pair of side wall portions receive the fastening force of the bolt.

According to this structure, since the support-bracket connection portion interconnecting the pair of side wall portions has the bending deformation portion, the pair of side wall portions can be made close to each other due to bending deformation of the bending-deformation portion when receiving the fastening force of the bolt. Thereby, the fastening force of the bolt can be uniformly transmitted to the pair of upper-side pressing portions and the pair of lower-side pressing portions of the biasing member arranged between the side wall portions and the support-side column. Consequently, the support-side column pressed by the pair of upper-side pressing portions and the pair of lower-side pressing portions of the biasing member can be stably fixed between the pair of side wall portions.

In the above-described steering device, it is preferable that the biasing member further have a pair of support portions extending in the vehicle longitudinal direction and supporting the pair of upper-side pressing portions and the pair of lower-side pressing portions, respectively, and a biasing-member connection portion to interconnect vehicle-forward-side end portions of the pair of support portions, and the pair of support portions be configured to be bending-deformed toward an inward side, in the vehicle width direction, thereof when the pair of upper-side pressing portions and the pair of lower-side pressing portions receive the fastening force of the bolt.

According to this structure, since the pair of support portions supporting the upper-side pressing portions and the lower-side pressing portions, respectively, come to be are bending-deformed toward the inward side, in the vehicle width direction, thereof when the upper-side pressing portions and the lower-side pressing portions receive the fastening force of the bolt, the support-side column pressed by the pair of upper-side pressing portions and the pair of lower-side pressing portions of the biasing member can be stably fixed between the pair of side wall portions.

As described above, the steering device of the present invention can properly fix the column to support the shaft at the high fastening rigidity and conduct the tilting and axial moving of the column smoothly in the event of releasing the bolt's fastening.

The present invention will become apparent from the following description which refers to the accompanying drawings.

DETAILED DESCRIPTION OF THE INVENTION

Hereafter, a steering device according to an embodiment of the present invention will be described specifically referring to the drawings.

A steering device1of the present embodiment shown inFIGS.1-6is arranged along a vehicle longitudinal direction X in such a manner that it protrudes toward a cabin inside from an engine room provided in a vehicle body of an automotive vehicle, which is used as the steering device of a vehicle.

This steering device1is configured such that a steering shaft composed of an upper shaft2and a lower shaft4is configured to be expandable and tiltable and also be fixable at the desired length and angle.

Specifically, the steering device1comprises the upper shaft2, an upper column3which rotatably supports the upper shaft2, the lower shaft4which is connected to a front end portion (an end portion at a vehicle forward side X1) of the upper shaft2so as to slide in an axial direction, a lower column portion11(lower column) which rotatably supports the lower shaft4and includes an upper-column biasing portion12(biasing member), a support bracket6which supports the upper column3, a pair of pressing plates7which are arranged on both sides, in a vehicle width direction Y, of the support bracket6, a bolt9and a nut14which are together operative to fasten the support bracket6and the pair of pressing plates7from respective outward sides, in the vehicle width direction Y, thereof, a lever8as a bolt operational portion which is connected to a head-side portion of the bolt9and operative to change a fastening force of the bolt9by rotating the bolt9, and an outer-column support bracket13which supports so that the outer column5can tilt in a vertical direction Z. Herein, since the nut14is fixed at an outer face of the pressing plate7without rotation, the bolt9can be fastened or released by a driver's operation of the lever8. Further, the lever8is specifically configured such that a cam18attached to the bolt9is rotatably operated so as to ride on or down, thereby changing a state where the fastening force of bolt9is generated or not.

The support bracket6and the outer-column support bracket13are fixed at the vehicle body by bolts or the like. By weakening the fastening force of the bolt9by an operation of the lever8, the upper shaft2, the upper column3, the lower shaft4, the outer column5, and the pair of pressing plates7are made tiltable in the vertical direction Z around a support axis13aof the outer-column support bracket13(see a tilt direction T shown inFIG.1). At the same time, the upper shaft2and the upper column3are made slidable in the vehicle longitudinal direction X relative to the lower shaft4and the outer column5(see a slide direction S shown inFIG.1). After the upper shaft2is moved to the angle and longitudinal position, in the longitudinal direction X, desired by an operator, the fastening operation of the bolt9can easily make the steering device1return to its fixing state.

Hereafter, each component of the steering device1will be described.

The upper shaft2is a bar-shaped member extending in the vehicle longitudinal direction X, and a steering wheel (not illustrated) is fixed to its rear end portion (an end portion at a vehicle rearward side X2).

The upper column3is a cylindrical member rotatably supporting the upper shaft2. The upper column3includes plural bearings31(seeFIGS.1,5-6, and12) which support front-and-rear end portions of the upper shaft2.

In the present embodiment, as shown inFIGS.4and5, a rectangular protrusion portion3awhich protrudes downward is formed in a certain area of a lower-side portion of the upper column3which overlaps, in the vehicle longitudinal direction X, the upper-column biasing portion12. The bolt9penetrates this rectangular protrusion portion3ain the vehicle width direction Y. Further, the rectangular protrusion portion3ais exposed to a downward side through a rectangular opening12aof the upper-column biasing portion12. Herein, since the rectangular opening12ahas a wider width, in the longitudinal direction, X than the rectangular protrusion portion3a, the upper-column biasing portion12does not prevent a move, in the longitudinal direction X, of the upper column3.

The lower shaft4is a bar-shaped member which is connected to the front end portion (the end portion at the vehicle forward side X1) of the upper shaft2so as to slide in the axial direction. More specifically, the lower shaft4has a telescopic structure (seeFIG.12) in which the lower shaft4is slidable in the axial direction relative to the upper shaft2, and the lower shaft4is coupled to the upper shaft2(e.g., via a spline coupling) in such a manner that it can rotate together with the upper shaft2.

As shown inFIGS.7-9, the outer column5is a member which includes the lower column portion11(lower column) which rotatably supports the lower shaft4and the upper-column biasing portion12(biasing member). In other words, the outer column5of the present embodiment is constituted by the lower column portion11(lower column) and the upper-column biasing portion12(biasing member) which are integrated.

The lower column portion11is a portion which is movable in the axial direction (vehicle longitudinal direction X) relative to the upper column3as well as rotatably supports the lower shaft4. In the present embodiment, a whole part of the outer column5including the lower column portion11is movable in the axial direction (vehicle longitudinal direction X) relative to the upper column3as well.

The lower column portion11has a bearing32(seeFIG.1) which rotatably supports an end portion at the vehicle forward side X1of the lower shaft4inside its cylindrical body.

The upper-column biasing portion12is the biasing member which is arranged between a pair of side wall portions61(described later) (seeFIGS.3,5,6,10and11) of the support bracket6and the upper column3and also operative to apply a pressing force to the upper column3toward its axial center O from the both sides, in the vehicle width direction Y, thereof when the pair of side wall portions61receive the fastening force of the bolt9.

As shown inFIGS.6-9, the upper-column biasing portion12comprises at least a pair (front-and-rear two pairs in the present embodiment) of upper-side pressing portions21which are provided to press a portion of the upper column3which is above the axial center O of the upper column3toward the axial center O from the both sides, in the vehicle width direction Y, thereof, at least a pair (front-and-rear two pairs in the present embodiment) of lower-side pressing portions22which is provided to press another portion of the upper column3which is below the axial center O toward the axial center O from the both sides, in the vehicle width direction Y, thereof, and a pair of side wall portions25which support the pair of upper-side pressing portions21and the pair of lower-side pressing portions22on the both sides, respectively.

Each of the side wall portions25has a bolt insertion hole26for insertion of the bolt9at a position overlapping a tilting long hole63(described later) (seeFIGS.7,10and11) which is formed at the side wall portion61of the support bracket6.

In the present embodiment, the pair of upper-side pressing portions21and the pair of lower-side pressing portions22are positioned at least on the vehicle rearward side X2of the tilting long holes63.

More specifically, the pair of upper-side pressing portions21and the pair of lower-side pressing portions22of the present embodiment are arranged on the forward-and-rearward both sides, in the vehicle longitudinal direction X, of the tilting long holes63, respectively.

The upper-side pressing portion21and the lower-side pressing portion22are arranged on the inward side, in the vehicle width direction Y, of the side wall portion25(on a facing side of the pair of side wall portions25). In the present embodiment, the upper-side pressing portion21and the lower-side pressing portion22are integrally formed with the side wall portion25, which are specifically formed by a plate-shaped portion which is configured to bend inwardly, in the vehicle width direction Y, from upper-and-lower both end portions of the side wall portion25.

At an outward face, in the vehicle width direction Y, of each of the side wall portions25are formed an upper-side convex portion23and a lower-side convex portion24which respectively protrude outwardly, in the vehicle width direction Y, from the above-described outward face at respective positions corresponding to the upper-side pressing portion21and the lower-side pressing portion22.

In the present embodiment, the upper-column biasing portion12further comprises a pair of support portions15which extend toward the vehicle forward side X1, in the vehicle longitudinal direction X, from respective front end portions of the pair side wall portions25(from respective end portions at the vehicle forward side X1) and a connection portion16(corresponding to a “biasing-member connection portion” in the claims) to interconnect respective end portions at the vehicle forward side X1of the pair of support portions15.

The pair of support portions15respectively support the upper-side pressing portions21and the lower-side pressing portions22via the pair of side wall portions25. The pair of support portions15are configured to be bending-deformed toward the inward side, in the vehicle width direction Y, thereof when the pair of upper-side pressing portions21and the pair of lower-side pressing portions22receive the fastening force of the bolt9. Specifically, as shown inFIG.7, the support portion15is a plate-shaped portion which is bendable in the vehicle width direction Y, and its end portion at the vehicle forward side X1is fixed to the connection portion16, thereby forming a cantilever-beam state. An end portion at the vehicle rearward side X2of the support portion15is connected to the upper-side pressing portion21and the lower-side pressing portion22. When the fastening force of the bolt9inserted into the bolt insertion holes26is applied to the pair of side wall portions25, this force is transmitted to the upper-side pressing portions21and the lower-side pressing portions22, so that the pair of plate-shaped support portions15are bending-deformed inwardly, in the vehicle width direction, thereof.

The connection portion16of the present embodiment further comprises a pair of side wall portions16awhich are arranged on the both sides, in the vehicle width direction Y, of the lower column portion11and connected to the respective end portions at the vehicle forward side X1of the pair of support portions15and a bottom-wall portion16bwhich extends in the vehicle width direction Y below the lower column portion11and interconnects respective lower ends of the pair of side wall portions16a. The connection portion16further comprises a pair of column connection portions16cwhich respectively interconnect the pair of side wall portions16aand the lower column portion11.

The outer column5of the present embodiment includes a pair of plate-shaped arm portions17which extend toward the vehicle forward side X1further from the respective front end portions of the pair of side wall portions16aof the connection portion16. An axial hole17ais formed at each end portion at the vehicle forward side X1of the pair of arm portions17. A support axis13aof the outer-column support bracket13shown inFIGS.1and3is rotatably supported at the axial hole17a. Thereby, the outer column5is supported at the outer-column support bracket13so as to tilt in the vertical direction Z around the support axis13a(see the tilt direction T inFIG.1).

The support bracket6is a member which is fixed to the vehicle body and supports a support-side column which is either one of the lower column portion11and the upper column3, specifically the upper column3in the present embodiment.

Specifically, the support bracket6comprises, as shown inFIGS.10and11, the pair of side wall portions61which are provided to interpose the upper column3from the both sides, in the vehicle width direction Y, thereof and where the tilting long holes63extending in the vertical direction Z are formed, a connection portion62(corresponding to a “support-bracket connection portion” in the claims) which interconnects the pair of side wall portions61, and plural (four, in the present embodiment shown inFIG.10) vehicle-body connection portions64which are connected to the vehicle body.

The connection portion62has a bending deformation portion62awhich is operative to be bending-deformed in a direction where respective upper portions of the pair of side wall portions61approach each other when the pair of side wall portions61receive the fastening force of the bolt9. The bending deformation portion62ashown inFIG.10is a portion which is formed by downward bending a middle part, in the vehicle width direction Y, of the plate-shaped connection portion62extending in the vehicle width direction Y so that the connection portion62can bend easily. That is, the connection portion62with the bending deformation portion62ashown inFIG.10is of a M-letter shape when viewed along the vehicle longitudinal direction X. Thus, since the bending deformation portion62ais deformed when the pair of side wall portions61receive the fastening force of the bolt9, the connection portion62with the bending deformation portion62acan be easily deformed in the direction where the respective upper portions of the pair of side wall portions61approach each other.

As shown inFIGS.1-6, the pair of pressing plates7are respectively arranged on the outward side, in the vehicle width direction Y, of the pair of side wall portions61of the support bracket6. The pair of pressing plates7press the pair of side wall portions61inwardly, in the vehicle width direction Y, thereof when receiving the fastening force of the bolt9.

Each of the pair of pressing plates7has an insertion hole7awhere the bolt9is inserted. Further, the pair of pressing plates7have at least a single upper-side convex portion7band at least a single lower-side convex portion7cwhich protrude toward the side wall portions61at respective positions which face the pair of upper-side pressing portions21and the pair of lower-side pressing portions22, interposing the side wall portions61therebetween. In the present embodiment, as shown inFIG.3, the upper-side convex portions7band the lower-side convex portions7aare arranged on the forward-and-rearward both sides of the insertion holes7a.

As shown inFIG.5, the bolt9penetrates, from the left side, through the insertion holes7aof the pair of pressing plates7, the tilting long holes63of the pair of side wall portions61of the support bracket6, the bolt insertion holes26of the pair of side wall portions25of the upper-column biasing portion12, and also penetrates the protrusion portion3aof the upper column3. Thus, the pair of pressing plates7, the support bracket6, the upper-column biasing portion12, and the upper column3can be connected by the single bolt9.

As shown inFIG.1, the lever8comprises a root-side end portion8bwhich is connected to the bolt9and an operational-side end portion8awhich is positioned on the vehicle rearward side X2of the bolt9and operative to receive an operational force from outside. By applying the operational force to the operational-side end portion8aof the lever8in the vertical direction Z, the fastening force can be applied to the bolt9which is connected to the root-side end portion8band inserted into the tilting long holes63or the bolt9can be loosened.

Features of Present Embodiment

The above-described steering device1of the present embodiment comprises the tilt-telescopic mechanism operative10to switch the state of the support-side column between the movable state where the upper column3is allowed to tilt in the vertical direction Z and move in the axial direction (vehicle longitudinal direction X) and the prohibited state where the upper column's tilting and moving is prohibited. Specifically, the tilt-telescopic mechanism10includes the pair of side wall portions61provided at the support bracket6, the bolt9penetrating the pair of side wall portions61through the tilting long holes63and producing the fastening force to press the pair of side wall portions61against each other in the approaching direction, the lever8operative to change the fasting force by rotationally operating the bolt9, and the upper-column biasing portion12(biasing member) arranged between each of the pair of side wall portions61and the upper column3and operative to apply the pressing force to the upper column3toward its axial center O from the both sides, in the vehicle width direction Y, thereof when the pair of side wall portions61receive the fastening force.

By applying the operational force to the operational-side end portion8aof the lever8in the vertical direction Z, the fastening force of the bolt9can be increased or decreased. Thus, the function of the tilt-telescopic mechanism10, that is-switching the state of the upper column3between the movable state and the prohibited state can be performed.

As shown inFIGS.6and7, the upper-column biasing portion12comprises at least the pair (front-and-rear two pairs in the present embodiment) of upper-side pressing portions21pressing the portion of the upper column3which is above its axial center O from the both sides, in the vehicle width direction Y, thereof and at least the pair (front-and-rear two pairs in the present embodiment) of lower-side pressing portions22pressing the other portion of the upper column3which is below its axial center O from the both sides, in the vehicle width direction Y, thereof.

Accordingly, when the pair of side wall portions61receive the fastening force of the bolt9, since the upper-and-lower both sides of the axial center O of the upper column3are pressed from the both sides, in the vehicle width direction Y, thereof by the pair of upper-side pressing portions21and the pair of lower-side pressing portion22of the upper-column biasing portion12, the upper column3comes to be restrained at four separated points, in a peripheral direction, thereof in its axial-direction (vehicle longitudinal direction X) view. Consequently, the upper column3can be fixed at the high fastening rigidity between the pair of the side wall portions61.

Meanwhile, in the releasing state where the pair of side wall portions61do not receive the fastening force, the upper-and-lower both sides of the axial center O of the upper column3do not receive any pressing force from the upper-column biasing portion12. Consequently, the vertical tilting and axial moving of the upper column3can be conducted smoothly.

In the steering device1of the present embodiment, the bolt operational portion is the lever8operative to change the fastening force of the bolt9inserted into the tilting long holes63. As shown inFIG.1, the lever8comprises the root-side end portion8bconnected to the bolt9and the operational-side end portion8apositioned on the vehicle rearward side X2of the bolt9and operative to receive the operational force from outside. The pair of upper-side pressing portions21and the pair of lower-side pressing portions22are arranged on the vehicle rearward side X2of the tilting long holes63at least (in the present embodiment, the pair of upper-side pressing portions21and the pair of lower-side pressing portions22are arranged on the forward-and-rearward both sides of the tilting long holes63).

According to this structure, the pair of upper-side pressing portions21and the pair of lower-side pressing portions22of the upper-column biasing portion12are arranged on the vehicle rearward side X2of the position of the bolt9inserted into the tilting long holes63. Therefore, the position of the connection portion where the root-side end portion8bof the lever8is connected to the bolt9can be shifted toward the vehicle forward side X1from the position of the upper-side pressing portion21and the lower-side pressing portion22which fix the upper column3. Thereby, the length of the lever8can be properly long without changing the position, in the vehicle longitudinal direction X, of the operational-side end portion8aof the lever8. Accordingly, the fastening force of the bolt9can be properly large without increasing the operational force applied to the operational-side end portion8a. Consequently, the operability of the lever8can improve.

For example, positional relationships of the lever8, the bolt9, and the front-and-rear pressing portions21may be considered with a use of a simplified model shown inFIG.12. A portion where the upper-column biasing portion12receives the fastening force of the bolt9is the upper-side convex portion23which contacts the side wall portion61of the support bracket6. Herein, in a case where an axial center C of the bolt9is considered as a standard position, the length from the upper-side convex portion23to the axial center C of the bolt9is defined as L1. Next, a portion where the upper-column biasing portion12applies the fastening force to the upper column3is the upper-side pressing portion21. Herein, the length from the upper-side pressing portion21to the axial center C of the bolt9is defined as L2. Meanwhile, a portion which receives the operational force from the outside for applying the fastening force to the bolt9is the operational-side end portion8aof the lever8. The length from the operational-side end portion8ato the axial center C of the bolt9is defined as L3.

As shown inFIG.12, the right-side upper-side pressing portion21which is positioned on the right side is arranged on the vehicle rearward side X2(right side) of the position of the bolt9. According to the positional relationships shown inFIG.12, the length L3between the operational-side end portion8aand the axial center C can be set to be longer than the length L1between the upper-side convex portion23and the axial center C or the length L2between the upper-side pressing portion21and the axial center C. Therefore, the connection portion where the root-side end portion8bof the lever8and the bolt9are connected can be shifted toward the vehicle forward side X1from the above-described right-side upper-side pressing portion21which fixes the upper column3. Accordingly, the length of the lever8can be made properly long without changing the position, in the vehicle longitudinal direction X, of the operational-side end portion8aof the lever8.

In the steering device1of the present embodiment, as shown inFIG.7, the pair of upper-side pressing portions21and the pair of lower-side pressing portions22are arranged on the forward-and-rearward both sides, in the vehicle longitudinal direction X, of the tilting long holes63, respectively.

According to this structure, the pair of upper-side pressing portions21and the pair of lower-side pressing portions22of the upper-column biasing portion12are respectively arranged at the two separated points, in the longitudinal direction X, thereof in such a manner they enclose the tilting long holes63formed at the side wall portions61in the view of the vehicle width direction Y. Therefore, the pair of side wall portions61can stably fix the upper column3by supporting at the front-and-rear two points of the upper-side pressing portion21and the front-and-rear two points of the lower-side pressing portion22which enclose the tilting long holes63in the vehicle-width-direction view (in the view of the vehicle width direction Y), i.e., at a total of four points of the pressing portions.

The steering device1of the present embodiment further comprises, as shown inFIGS.1-6, the pair of pressing plates7arranged on the respective outward sides, in the vehicle width direction Y, of the pair of side wall portions61and operative to press the pair of side wall portions61to the respective inward sides, in the vehicle width direction Y, thereof when receiving the fastening force of the bolt9. This pair of pressing plates7respectively have the upper-side convex portions7band the lower-side convex portions7cwhich protrude toward the side wall portions61at the respective positions which face the pair of upper-side pressing portions21and the pair of lower-side pressing portions22, interposing the side wall portions61therebetween.

According to this structure, when the pressing plates7receive the fastening force of the bolt9, the upper-side convex portions7band the lower-side convex portions7ccan press the upper-side pressing portions21and the lower-side pressing portions22of the upper-column biasing portion12via the side wall portions61. Thereby, the fastening force of the bolt9can be effectively transmitted to the upper-side pressing portions21and the lower-side pressing portions22of the upper-column biasing portion12. As a result, the upper column3pressed by the pair of upper-side pressing portions21and the pair of lower-side pressing portions22of the upper-column biasing portion12can be stably fixed between the pair of side wall portions61.

Further, in the present embodiment, at the outward (back side) face, in the vehicle width direction Y, of each of the side wall portions25of the upper-column biasing portion12are formed the upper-side convex portion23and the lower-side convex portion24which respectively protrude outwardly, in the vehicle width direction Y, from the above-described outward face at the respective positions corresponding to the upper-side pressing portion21and the lower-side pressing portion22. Accordingly, when the pressing plates7receive the fastening force of the bolt9, the upper-side convex portions7band the lower-side convex portions7cof the pressing plates7respectively press the upper-side convex portions23and the lower-side convex portions24which protrude outwardly, in the vehicle direction, of the upper-column biasing portion12in a pin-point manner, so that the pressing force can be effectively transmitted from the upper-side convex portions23and the lower-side convex portions24to the upper-side pressing portions21and the lower-side pressing portions22which are positioned on the inward sides, in the vehicle width direction, of these portions23,24. Therefore, the upper-side pressing portions21and the lower-side pressing portions22of the upper-column biasing portion12can properly fix the upper column3, effectively pressing that, even if the operational force applied of the lever8is not so strong.

In the steering device1of the present embodiment, the support bracket6further comprises the connection portion62to interconnect the pair of side wall portions61. This connection portion62has the bending deformation portion62aoperative to be bending-deformed in the direction where the pair of side wall portions61approach each other when the pair of side wall portions61receive the fastening force of the bolt9.

According to this structure, since the connection portion62interconnecting the pair of side wall portions61has the bending deformation portion62a, the pair of side wall portions61can be made close to each other due to bending deformation of the bending-deformation portion62awhen receiving the fastening force of the bolt9. Thereby, the fastening force of the bolt9can be uniformly transmitted to the pair of upper-side pressing portions21and the pair of lower-side pressing portions22of the upper-column biasing portion12arranged between the side wall portions61and the upper column3. Consequently, the upper column3pressed by the pair of upper-side pressing portions21and the pair of lower-side pressing portions22of the upper-column biasing portion12can be stably fixed between the pair of side wall portions61.

In the steering device1of the present embodiment, the upper-column biasing portion12further has the pair of support portions15extending in the vehicle longitudinal direction X and supporting the pair of upper-side pressing portions21and the pair of lower-side pressing portions22, respectively, and the connection portion16to interconnect the respective end portions at the vehicle forward side X1of the pair of support portions15. The pair of support portions15are configured to be bending-deformed toward the inward side, in the vehicle width direction Y, thereof when the pair of upper-side pressing portions21and the pair of lower-side pressing portions22receive the fastening force of the bolt9(for example, the support portion15is made of a M-letter shaped plate member deformable in the vehicle width direction Y). According to this structure, since the pair of support portions15supporting the upper-side pressing portions21and the lower-side pressing portions22, respectively, come to be bending-deformed toward the inward side, in the vehicle width direction Y, thereof when these portions21,22receive the fastening force of the bolt9, the upper column3pressed by the pair of upper-side pressing portions21and the pair of lower-side pressing portions22of the upper-column biasing portion12can be stably fixed between the pair of side wall portions61.

Modified Examples

While the above-described embodiment is configured such that the upper-column biasing portion12which press the lower column portion11rotatably supporting the lower shaft4and the upper column3is included in the outer column5, the present invention is not limited to this. The lower column portion11and the upper-column biasing portion12may be made as separated independent parts. That is, the lower column portion11may be a cylindrical-shaped unit member, and the upper-column biasing portion12may be another unit member which comprises at least the pair of upper-side pressing portions21and the lower-side pressing portions22.

The steering device1of the above-described embodiment has the supporting structure of the upper column3, in which the support bracket6supports the upper column3and the upper-column biasing portion12comprises at least the pair of upper-side pressing portions21pressing the portion of the upper column3which is above the axial center O of the upper column3from the both sides, in the vehicle width direction Y, thereof and the pair of lower-side pressing portions22pressing the other portion of the upper column3which is below the axial center O from the both sides, in the vehicle width direction Y, thereof. However, the present invention is not limited to this supporting structure.

The present invention can be achieved as long as the support bracket supports the support-side column which is either one of the lower column and the upper column and the biasing member comprises at least a pair of upper-side pressing portions provided to press a portion of the support-side column which is above the axial center of the support-side column from the both sides, in the vehicle width direction, thereof and at least a pair of lower-side pressing portions provided to press another portion of the support-side column which is below the axial center of the support-side column from the both sides, in the vehicle width direction, thereof.

Therefore, a structure in which the support bracket supports the lower column and at least the pair of upper-side pressing portions and at least the pair of lower-side pressing portions press the upper-side portions and the lower-side portions of the lower column toward its axial center can be included in the scope of the present invention as well.

While the lever8is exemplified as the bolt operational portion operative to change the fastening force of the bolt9through its rotational operation in the above-described embodiment, the present invention is not limited to this. Any portion can be included in the bolt operational portion of the present invention as long as it is capable of changing the fastening force of the bolt by rotating the bolt9. For example, an electromotive actuator to rotatably operate a bolt is applicable as well.