Steering column device

Abstract

A steering column device comprising a long hole through which an adjusting rod is inserted and a mounting hole, wherein a friction disc is sandwiched in at least any one of a part between an inner-side surface of any one of a pair of support plate portions and an outer-side surface of a column-side bracket of a steering column and a part between an outer-side surface of any one of the pair of support plate portions and an inner-side surface of any one of a pair of pressing portions. This steering column device has a hook portion that has a cantilever beam structure and a restriction projection for restricting movement of the friction disc in the width direction, the hook portion being inserted through the mounting hole in the width direction.

Description

Technical Field

[0001] The present invention relates to a steering column device.

Background Art

[0002] In a steering device for an automobile, a steering wheel position adjusting device is incorporated that enables adjustment of the vertical position and the front-rear position of the steering wheel according to the physique and driving posture of the driver.

[0003] Figs. 14 to 16 show an example of a steering device provided with a steering wheel position adjusting device described in Japanese Unexamined Patent Application Publication No. 2011-148487.

[0004] The steering shaft 100 is rotatably supported inside the steering column 101. A steering wheel is fixed to the rear end portion of the steering shaft 100. The steering shaft 100 has a structure in which an inner shaft 102 disposed forward and an outer shaft 103 disposed rearward are combined by spline engagement or the like so as to be able to transmit torque and be telescopically extendable in order to enable adjustment of the front-rear position of the steering wheel. Here, the front-rear direction means the front-rear direction of the vehicle, the vertical direction means the vertical direction of the vehicle, and the width direction means the width direction of the vehicle.

[0005] The steering column 101 has a substantially cylindrical shape and is supported with respect to the vehicle body. The steering column 101 is configured to be telescopically extendable by loosely fitting the front side portion of the outer column 105 disposed rearward to the rear side portion of the inner column 104 disposed forward so as to enable relative displacement in the axial direction in order to enable adjustment of the front-rear position of the steering wheel.

[0006] On the front side of the outer column 105, a column-side bracket 107 composed of a pair of sandwiched plate portions 106 is provided. The column-side bracket 107 is sandwiched from both sides in the width direction by a pair of support plate portions 109 provided on a vehicle-body-side bracket 108 supported by the vehicle body. An adjustment rod 112 is inserted in the width direction through a column-side through hole 110 penetrating each of the pair of sandwiched plate portions 106 in the width direction and a vehicle-body-side through hole 111 penetrating each of the pair of support plate portions 109 in the width direction. In the conventional structure described in Japanese Patent Application Laid-Open No. 2011-148487, in order to enable adjustment of the front-rear position of the steering wheel, the column-side through hole 110 is formed by a long hole extending in the front-rear direction. Further, in order to enable adjustment of the up-down position of the steering wheel, the vehicle-body-side through hole 111 is formed by a long hole extending in the up-down direction.

[0007] An anchor portion (head portion) 113 is provided at the base end portion of the adjustment rod 112, and a retaining member 114 is attached to the tip end portion of the adjustment rod 112. A cam device 115 and an adjustment lever 116 are provided between the anchor portion 113 and the support plate portion 109 on one side in the width direction (the left side in FIG. 16).

[0008] The cam device 115 is composed of a movable-side cam 117 and a fixed-side cam 118. The movable-side cam 117 is externally fitted and supported on the adjustment rod 112 and has a movable-side cam surface which is an uneven surface in the circumferential direction on the inner surface (the right side surface in FIG. 16) regarding the width direction of the vehicle body. The fixed-side cam 118 is supported so as not to be relatively rotatable with respect to the support plate portion 109 on one side in the width direction and has a fixed-side cam surface which is an uneven surface in the circumferential direction on the outer surface (the left side surface in FIG. 16) regarding the width direction of the vehicle body facing the movable-side cam surface.

[0009] The base of the adjustment lever 116 is fixed non-rotatably relative to the movable-side cam 117. Based on the operation of the adjustment lever 116, the cam device 115 relatively rotates the movable-side cam 117 with respect to the fixed-side cam 118, thereby changing the rotational phase between the movable-side cam surface and the fixed-side cam surface and expanding or contracting the dimension in the width direction. As a result, it is possible to expand or contract the distance between the pair of support plate portions 109 and adjust the magnitude of the force for clamping the pair of clamped plate portions 106.

[0010] In the unlocked state where the dimension in the width direction of the cam device 115 is reduced and the force for clamping the pair of clamped plate portions 106 by the pair of support plate portions 109 is decreased, the position of the steering wheel can be adjusted within the range where the adjustment rod 112 can be displaced inside the column-side through hole 110 and the vehicle body-side through hole 111. On the other hand, in the locked state where the dimension in the width direction of the cam device 115 is increased and the force for clamping the pair of clamped plate portions 106 by the pair of support plate portions 109 is increased, the steering wheel can be held at the adjusted position.

[0011] In order to increase the force for holding the steering wheel at the adjusted position, friction units 119 are respectively clamped between the portion between the outer surface of the support plate portion 109 on one side in the width direction and the inner surface of the fixed-side cam 118, and the portion between the outer surface of the support plate portion 109 on the other side in the width direction and the inner surface of the retaining member 114. The friction unit 119 is configured by alternately stacking a plurality of telescopic friction plates 120 and a plurality of washers 121.

[0012] The telescopic friction plate 120 is configured in a flat plate shape, extends in the front-rear direction, and has a longitudinal hole 122 in the front-rear direction through which the adjustment rod 112 is inserted. The telescopic friction plate 120 has a mounting hole 123, which is a circular hole, on the front side of the longitudinal hole 122 in the front-rear direction. The telescopic friction plate 120 is supported with respect to the outer column 105 by inserting a hook portion (pin) 124 having a cantilever structure provided on the outer peripheral surface of the outer column 105 inside the mounting hole 123. The adjustment rod 112 is inserted through a through hole provided in the central portion of the washer 121. By providing such a friction unit 119, the frictional area is increased and the force for holding the steering wheel in the adjusted position is increased.

Prior Art Documents

Patent Documents

[0013]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0014] In the conventional structure described in Japanese Patent Application Laid-Open No. 2011-148487, when the cam device 115 is unlocked, the amount of movement of the telescopic friction plate 120 in the width direction with respect to the hook portion 124 may increase.

[0015] That is, the telescopic friction plate 120 is generally formed by subjecting a coil material to press working. The coil material is corrected using a roller leveler or the like to remove its curl or distortion, but it is difficult to completely remove the curl and distortion. For this reason, when the cam device 115, which releases the force clamping the telescopic friction plate 120 in the width direction, is unlocked, the telescopic friction plate 120 is likely to bend or warp such that the outer surface or the inner surface becomes a concave surface. Further, in the conventional structure described in Japanese Patent Application Laid-Open No. 2011-148487, the hook portion 124 is configured by a simple cylindrical shape whose outer diameter does not change over the entire length.

[0016] For this reason, as shown in FIG. 17, when the cam device 115 is unlocked, among the telescopic friction plates 120 arranged on the outermost side in the width direction, the amount of movement in the width direction of the telescopic friction plate 120 on one side (the upper side in FIG. 17) whose outer surface is curved to be concave with respect to the engaging portion 124 increases, and the engagement margin with respect to the engaging portion 124 may decrease.

[0017] The present invention has been made to solve the above problems, and an object thereof is to provide a steering column device capable of restricting the movement in the width direction of a friction plate with respect to an engaging portion.

Means for Solving the Problems

[0018] A steering column device according to an aspect of the present invention includes a steering column, a vehicle body side bracket, an adjustment rod, a pair of pressing portions, an expansion and contraction mechanism, a friction plate, and an engaging portion.

[0019] The steering column includes a column side bracket having a column side through hole penetrating in the width direction.

[0020] The vehicle body side bracket is disposed on both sides in the width direction of the column side bracket, and includes a pair of support plate portions each having a vehicle body side through hole penetrating in the width direction.

[0021] The adjustment rod is inserted through the column side through hole and the pair of vehicle body side through holes in the width direction.

[0022] The pair of pressing portions are provided at portions of the adjustment rod that protrude in the width direction from the outer surfaces of the pair of support plate portions, respectively.

[0023] The expansion and contraction mechanism expands and contracts the distance between the pair of pressing portions.

[0024] The friction plate extends in a direction in which the position of the steering wheel can be adjusted, and has a long hole through which the adjustment rod is inserted and a mounting hole. The friction plate is sandwiched at least between a portion between the inner surface of one of the pair of support plate portions and the outer surface of the column side bracket and a portion between the outer surface of one of the pair of support plate portions and the inner surface of one of the pair of pressing portions.

[0025] The engaging portion has a cantilever structure and passes through the mounting hole in the width direction.

[0026] The engaging portion has a limiting protrusion for restricting the movement of the friction plate in the width direction.

[0027] In the steering column device according to one aspect of the present invention, the limiting protrusion protrudes in a direction perpendicular to each of the width direction and the extending direction of the long hole.

[0028] When the long hole is a longitudinal long hole extending in the front-rear direction, the limiting protrusion protrudes upward or downward.

[0029] When the long hole is a vertical long hole extending in the vertical direction, the limiting protrusion protrudes forward or backward.

[0030] In the steering column device according to one aspect of the present invention, the limiting protrusion is provided integrally with the engaging portion on the outer peripheral surface of the end portion of the engaging portion.

[0031] In the steering column device according to one aspect of the present invention, the limiting protrusion is configured separately from the engaging portion and is fixed to the engaging portion.

[0032] In the steering column device according to one aspect of the present invention, the engaging portion is inserted into the mounting hole in a substantially non-rotatable manner relative to the mounting hole.

[0033] In the steering column device according to one aspect of the present invention, when the elongated hole is a longitudinally elongated hole extending in the front-rear direction, the engaging portion is provided on the outer peripheral surface of the steering column. In this case, the friction plate is constituted by a telescopic friction plate.

[0034] When the elongated hole is a vertically elongated hole extending in the vertical direction, the engaging portion is provided on the side surface of the support plate portion. In this case, the friction plate is constituted by a tilt friction plate.

[0035] In the steering column device according to one aspect of the present invention, the friction plate is curved in a free state so that its outer surface is a concave surface.

[0036] In the steering column device according to one aspect of the present invention, the steering column includes an outer column disposed on the front side, an inner column disposed on the rear side, and a support bracket.

[0037] The outer column includes a slit extending in the axial direction (front-rear direction), and a pair of sandwiched plate portions that are disposed on both sides in the width direction of the slit and each have a column-side through hole formed therein, and constitute the column-side bracket. The support bracket is disposed inside the slit and includes a mounting portion detachably attached to the inner column and the engaging portion. The elongated hole is a longitudinally elongated hole extending in the front-rear direction.

[0038] The friction plate is sandwiched one or more at a time between the inner surfaces of the pair of support plate portions and the outer surfaces of the pair of sandwiched plate portions. The support bracket includes two engaging portions. The limiting protrusion is provided on at least one of the two engaging portions. That is, the limiting protrusion may be provided on any of the two engaging portions. Alternatively, the limiting protrusion may be provided only on one of the two engaging portions, and may not be provided on the other of the two engaging portions.

[0039] In particular, in a configuration in which the limiting protrusion is provided only on one of the two hanging portions, and a plurality of the friction plates are sandwiched between the inner surfaces of the pair of support plate portions and the outer surfaces of the pair of sandwiched plate portions, among the plurality of friction plates through which the one hanging portion passes through the mounting hole, the friction plate disposed outermost in the width direction is disposed in a curved state such that its outer surface is a concave surface in a free state, and among the plurality of friction plates through which the other hanging portion passes through the mounting hole, the friction plate disposed outermost in the width direction is disposed in a curved state such that its outer surface is a convex surface in a free state.

Advantages of the Invention

[0040] According to one aspect of the present invention, there is provided a steering column device capable of restricting the movement of the friction plate in the width direction with respect to the hanging portion.

Brief Description of the Drawings

[0041]

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Figure 17

DETAILED DESCRIPTION OF THE INVENTION

[0042] [First Example] A first example of an embodiment of the present invention will be described with reference to FIGS. 1 to 12. In this example, the steering column device is incorporated in an electric power steering device for an automobile. In the following description, the front-rear direction means the front-rear direction of the vehicle to which the electric power steering device is assembled, the vertical direction means the vertical direction of the vehicle, and the width direction means the width direction of the vehicle, respectively.

[0043] 〔Overall Structure of Electric Power Steering Device〕 The electric power steering device 1 of this example is a column assist type electric power steering device. As shown in FIG. 1, the electric power steering device 1 includes a steering wheel 2, a steering shaft 3, a steering column device 4, a pair of universal joints 5a and 5b, an intermediate shaft 6, a steering gear unit 7, a pair of tie rods 8, and an electric assist device 9.

[0044] The steering wheel 2 is fixed to the rear end of the steering shaft 3. The steering shaft 3 is rotatably supported inside a steering column 19 that constitutes the steering column device 4. The front end of the steering shaft 3 is inserted inside a gear housing 10 fixed to the front end of the steering column 19 as shown in FIG. 2, and is connected to an output shaft 12 via a torsion bar 11.

[0045] The rotation of the output shaft 12 is transmitted to the pinion shaft 13 of the steering gear unit 7 via a pair of universal joints 5a and 5b and the intermediate shaft 6. The rotation of the pinion shaft 13 is converted into a linear motion of a rack shaft (not shown), and a pair of tie rods 8 are pushed and pulled, and a steering angle is imparted to the steered wheels.

[0046] The electric assist device 9 generates an auxiliary torque for reducing the force required for the driver to operate the steering wheel 2. The electric assist device 9 includes a gear housing 10, a torque sensor 14, an ECU (not shown), an electric motor 15, and a worm reducer 16.

[0047] The torque sensor 14 is disposed around the output shaft 12 and detects the torsional direction and amount of torsion of the torsion bar 11. The ECU determines the assist torque based on information regarding the steering torque calculated based on the torsional direction and amount of torsion of the torsion bar 11 detected by the torque sensor 14, and information regarding the vehicle speed measured by a vehicle speed sensor (not shown). The electric motor 15 is fixed to the gear housing 10, and the energization direction and amount are controlled by the ECU. The worm reducer 16 increases the torque of the electric motor 15 and transmits it to the output shaft 12. As a result, an assist torque is applied to the output shaft 12, and the pair of tie rods 8 are pushed and pulled with a force greater than the force applied to the steering wheel 2 by the driver.

[0048] 〔Steering Column Device〕 The steering column device 4 of this example is for rotatably supporting the steering shaft 3 with respect to the vehicle body, and includes a position adjustment mechanism (tilt mechanism and telescopic mechanism) capable of adjusting the vertical and front-rear positions of the steering wheel 2, and a shock absorption mechanism for alleviating the impact load applied to the driver's body during a secondary collision. In this example, in order to enable adjustment of the front-rear position of the steering wheel 2, the steering shaft 3 is configured by combining an inner shaft 17 disposed in the front and an outer shaft 18 disposed in the rear so as to be torque-transmittable and telescopable by spline engagement or the like.

[0049] The steering column device 4 includes a steering column 19 having a hook portion 42, a vehicle body side bracket 20, an adjustment rod 21, an adjustment lever 22 and a cam device 23 constituting an expansion and contraction mechanism, a thrust bearing 24, and a friction unit 52 having a telescopic friction plate 53. In this example, the thrust bearing 24 and the fixed-side cam 51 constituting the cam device 23 correspond to a pair of pressing portions, and the telescopic friction plate 53 corresponds to a friction plate.

[0050] 〈Steering Column〉 The steering column 19 has a substantially cylindrical shape, with its axial direction oriented in the front-rear direction and is supported with respect to the vehicle body. The steering column 19 is loosely fitted to the rear side portion of the outer column 25 arranged in the front and the front side portion of the inner column 26 arranged in the rear so as to allow relative displacement in the axial direction, in order to enable adjustment of the front-rear position of the steering wheel 2, and is configured to be able to expand and contract in the overall length. Inside the steering column 19, the steering shaft 3 is rotatably supported via a rolling bearing 27.

[0051] 《Outer Column》 The outer column 25 is made of metal such as an iron-based alloy or an aluminum-based alloy and is entirely configured in a cylindrical shape. The outer column 25 has its front end fixed to the gear housing 10 supported so as to be able to swing in the vertical direction with respect to the vehicle body, and its rear end supported with respect to the vehicle body side bracket 20. The outer column 25 has a slit 28 and a column side bracket 29.

[0052] The slit 28 is for enabling expansion and contraction of the inner diameter of the rear side portion of the outer column 25 and extends in the axial direction of the outer column 25. The slit 28 is provided from the front side portion to the rear end of the lower surface of the outer column 25. The slit 28 opens on both the inner peripheral surface and the outer peripheral surface of the outer column 25, and also opens on the rear end surface of the outer column 25.

[0053] The column side bracket 29 is provided at the rear end of the outer column 25. The column side bracket 29 is composed of a pair of sandwiched plate portions 30a, 30b arranged on both sides in the width direction of the slit 28. The pair of sandwiched plate portions 30a, 30b are configured in a substantially flat plate shape. The pair of sandwiched plate portions 30a, 30b extend in the vertical direction and are arranged at a distance in the width direction. In the portions of the pair of sandwiched plate portions 30a, 30b that are aligned with each other, column side through holes 31a, 31b penetrating in the width direction are formed. The pair of column side through holes 31a, 31b are arranged coaxially with each other. The column side through holes 31a, 31b are substantially circular holes.

[0054] The outer column 25 is provided with a bulging portion 32. The bulging portion 32 extends in the axial direction of the outer column 25 and bulges outward in the radial direction. The bulging portion 32 is provided from the middle portion to the rear portion of the upper part of the outer column 25. In this example, by providing the bulging portion 32 on the outer column 25, an accommodation space 33 is formed between the outer column 25 and the inner column 26.

[0055] 《Inner column》 The inner column 26 is made of metal such as an iron-based alloy or an aluminum-based alloy. The inner column 26 has a cylindrical shape as a whole.

[0056] As shown in FIG. 2, the steering column 19 of this example has a support bracket 34 having a hook portion 42 and a stopper member 35 in order to limit the adjustable range of the steering wheel 2 in the front-rear direction. Both the support bracket 34 and the stopper member 35 are attached to the outer peripheral surface of the inner column 26.

[0057] 《Support bracket》 The support bracket 34 has a function of supporting the telescopic friction plate 53 and a function of preventing the steering wheel 2 from being displaced excessively forward as a stopper mechanism on the contraction side. As shown in FIGS. 2 and 4, the support bracket 34 is detachably attached to the lower surface of the front end portion of the inner column 26. The support bracket 34 is made of metal and has a substantially T-shaped as a whole as shown in FIGS. 7 and 8. The support bracket 34 integrally has a mounting portion 36, a connecting portion 37, and a main body portion 38.

[0058] The mounting portion 36 is configured in a rectangular plate shape and is disposed inside the slit 28 provided in the outer column 25 as shown in FIG. 4. A slight gap is provided between the outer surface in the width direction of the mounting portion 36 and the inner surface in the width direction of the slit 28 so that the mounting portion 36 can move back and forth within the slit 28. The mounting portion 36 is detachably attached to the central portion in the width direction of the lower surface of Inner Column 26 using a plurality of (two in the illustrated example) shear pins 39 made of a material that is easily breakable, such as synthetic resin or an aluminum-based alloy. For this purpose, a plurality of through holes 36a are formed in the mounting portion 36.

[0059] The connecting portion 37 connects the front end portion of the mounting portion 36 and the upper surface of the central portion in the width direction of the main body portion 38 and extends in the vertical direction. A locking recess 40 recessed toward the rear is provided on the front end surface of the connecting portion 37. A cushioning material 41 (see FIG. 2) made of an elastic material is locked in the locking recess 40.

[0060] The main body portion 38 has a substantially U shape when viewed in the front-rear direction. The main body portion 38 is provided with a pair of hook portions 42 that extend in opposite directions with respect to the width direction at both end portions in the width direction and each have a cantilever structure. Each of the pair of hook portions 42 has a substantially square prism shape and is inserted in the mounting hole 56 of the telescopic friction plate 53 in the width direction.

[0061] In this example, when the steering wheel 2 is moved to the front end position within the adjustable range, the cushioning material 41 attached to the support bracket 34 abuts against the front end edge 28a of the slit 28. Thereby, the steering wheel 2 is prevented from being displaced further forward.

[0062] 《Stopper member》 The stopper member 35 constitutes a stopper mechanism on the extension side and has a function of preventing the steering wheel 2 from being excessively displaced rearward. As shown in FIG. 2, the stopper member 35 is attached to the central portion in the width direction on the upper surface of the front end portion of the inner column 26. The stopper member 35 is disposed in a housing space 33 formed inside the bulging portion 32 of the outer column 25.

[0063] In this example, when the steering wheel 2 is moved to the rear end position within the adjustable range, the stopper member 35 abuts against the abutting surface 32a facing forward among the inner surfaces of the bulging portion 32. Thereby, it is possible to prevent the steering wheel 2 from being further displaced rearward and the inner column 26 from coming out rearward from the outer column 25.

[0064] <Vehicle body side bracket> The vehicle body side bracket 20 supports the vehicle body such that the rear end portion of the outer column 25 can be switched between an unclamped state in which the vertical position and the front-rear position of the steering wheel 2 can be adjusted and a clamped state in which the steering wheel 2 is held in the adjusted position. The vehicle body side bracket 20 is made of a metal plate having sufficient rigidity such as steel or an aluminum-based alloy, and as shown in FIG. 3, has a pair of support plate portions 43a and 43b and a top plate portion 44.

[0065] The pair of support plate portions 43a and 43b are arranged on both sides in the width direction of the pair of sandwiched plate portions 30a and 30b that constitute the column side brackets 29. Each of the pair of support plate portions 43a and 43b is configured in a substantially flat plate shape. The pair of support plate portions 43a and 43b extend in the vertical direction, and the respective support plate portions 43a and 43b are arranged at intervals in the width direction. In each of the pair of support plate portions 43a and 43b, vehicle body side through holes 45a and 45b penetrating in the width direction are formed at mutually aligned portions. The vehicle body side through holes 45a and 45b are elongated holes extending in the vertical direction. More specifically, the vehicle body side through holes 45a and 45b are constituted by, for example, elongated holes extending in the arc direction centered on the swing center of the gear housing 10. When the tilt mechanism is not provided, the vehicle body side through hole is constituted by a simple circular hole.

[0066] The top plate portion 44 is arranged above the steering column 19. The upper end portions of each of the pair of support plate portions 43a and 43b are fixed to the lower surface of the top plate portion 44 by welding or the like. The top plate portion 44 is provided with a plurality of through holes 46 penetrating in the vertical direction. The top plate portion 44 is fixed to the vehicle body using fixing members such as bolts (not shown) inserted through the through holes 46.

[0067] 〈Adjustment Rod〉 The adjustment rod 21 is arranged such that its axial direction faces the width direction of the steering column device, and penetrates through the pair of column side through holes 31a and 31b and the pair of vehicle body side through holes 45a and 45b in the width direction. The total length of the adjustment rod 21 is longer than the interval between the outer surfaces of the pair of support plate portions 43a and 43b. The adjustment rod 21 is provided with an anchor portion 47 at the end portion (head portion) on one side in the width direction (the left side in FIG. 3), and a male screw portion 48 at the end portion on the other side in the width direction (the right side in FIG. 3).

[0068] Among the adjusting rods 21, around the portion protruding in the width direction from the outer surface of the support plate portion 43a disposed on one side in the width direction, an adjusting lever 22 and a cam device 23 are disposed in order from the outer side in the width direction. That is, between the inner surface of the anchor portion 47 and the outer surface of the support plate portion 43a in the width direction, the adjusting lever 22 and the cam device 23 are disposed. Among the adjusting rods 21, around the portion protruding in the width direction from the outer surface of the support plate portion 43b disposed on the other side in the width direction, a nut 49 and a thrust bearing 24 are disposed in order from the outer side in the width direction. The nut 49 is screwed onto the male screw portion 48 of the adjusting rod 21.

[0069] 〈Expansion and contraction mechanism and pair of pressing portions〉 The cam device 23 includes a movable-side cam 50 disposed on the outer side in the width direction and a fixed-side cam 51 disposed on the inner side in the width direction. The movable-side cam 50 is made of sintered metal and has a movable-side cam surface, which is an uneven surface in the circumferential direction, on the inner surface regarding the width direction of the vehicle body. The movable-side cam 50 is fixed to the base portion of the adjusting lever 22 and reciprocally rotates along with the reciprocating swing of the adjusting lever 22. Note that the base portion of the adjusting lever 22 and the movable-side cam 50 can be fixed to the adjusting rod 21 so as to rotate integrally with the adjusting rod 21, or can be externally fitted to the adjusting rod 21 so as to be relatively rotatable with respect to the adjusting rod 21.

[0070] The fixed-side cam 51 is made of sintered metal, has a fixed-side cam surface, which is an uneven surface in the circumferential direction, on the outer surface regarding the width direction of the vehicle body, and has a substantially rectangular engaging convex portion protruding inward in the width direction on the inner surface. The fixed-side cam 51 is externally fitted to the adjusting rod 21 to enable relative rotation with respect to the adjusting rod 21 and relative displacement in the width direction with respect to the adjusting rod 21. The fixed-side cam 51 engages the engaging convex portion with the vehicle body side through hole 45a of the support plate portion 43a disposed on one side in the width direction so as to enable only displacement along the vehicle body side through hole 45a.

[0071] The cam device 23 changes the rotational phase between the movable-side cam surface and the fixed-side cam surface by relatively rotating the movable-side cam 50 with respect to the fixed-side cam 51 based on the swinging operation of the adjustment lever 22, thereby expanding and contracting its dimension in the width direction. As a result, the distance between the fixed-side cam 51 of the cam device 23 and the thrust bearing 24 is expanded and contracted, and the distance between the pair of support plate portions 43a and 43b is expanded and contracted. In this example, the fixed-side cam 51 and the thrust bearing 24 of the cam device 23 correspond to a pair of pressing portions, and the adjustment lever 22 and the cam device 23 constitute an expansion and contraction device.

[0072] In this example, in order to increase the force for holding the steering wheel 2 at the adjusted position (especially the force for holding the position in the front-rear direction), the portion between the inner surface of the support plate portion 43a on one side in the width direction and the outer surface of the sandwiched plate portion 30a on one side in the width direction, and the inner surface of the support plate portion 43b on the other side in the width direction and the friction units 52 are respectively sandwiched between the outer surfaces of the sandwiched plate portions 30b on the other side in the width direction. In this example, each friction unit 52 is configured by alternately stacking one or more telescopic friction plates 53 and one or more fixed-side friction plates 54 in the width direction. In the illustrated example, each friction unit 52 is configured by sandwiching one fixed-side friction plate 54 between two telescopic friction plates 53.

[0073] 〈Friction Plate and Hooking Portion〉 The telescopic friction plate 53 is made of a metal coil material with a large friction coefficient with respect to the inner surfaces of the support plate portions 43a and 43b and the outer surfaces of the sandwiched plate portions 30a and 30b, and is manufactured by performing pressing and, if necessary, straightening processes. As shown in FIG. 10(A), the telescopic friction plate 53 has a flat plate shape and a substantially rectangular shape (substantially Y-shaped) that is long in the front-rear direction. As shown in FIG. 10(B), the telescopic friction plate 53 is curved in a free state such that one side surface thereof is a concave surface. That is, the telescopic friction plate 53 has a concave surface on one side surface and the other side SideThere is a bend (warp) such that it becomes a convex surface. Since the telescopic friction plate 53 is formed by punching a coil material from a predetermined direction using a press, each of the plurality of telescopic friction plates 53 has a bend in the same direction.

[0074] In this example, as shown in FIG. 11, in the unlocked state of the cam device 23 (the free state of the telescopic friction plate 53), a plurality of (two in the illustrated example) telescopic friction plates 53 arranged on one side in the width direction are arranged in a curved state such that their outer surfaces are concave, and a plurality of (two in the illustrated example) telescopic friction plates 53 arranged on the other side in the width direction are arranged in a curved state such that their outer surfaces are convex.

[0075] The telescopic friction plate 53 has a substantially rectangular longitudinal hole 55 that penetrates in the width direction and extends in the longitudinal direction over a range from the middle part to the rear end part in the longitudinal direction (length direction). In the illustrated example, the longitudinal hole 55 is configured in a slit shape and opens at the rear end edge of the telescopic friction plate 53. The adjustment rod 21 is inserted through the longitudinal hole 55 in the width direction. In this example, since the longitudinal hole 55 is configured in a slit shape, the telescopic friction plate 53 is more likely to have a larger bend than a telescopic friction plate having a longitudinal hole with a closed surrounding shape.

[0076] The telescopic friction plate 53 has a mounting hole 56 that penetrates in the width direction at the front end portion located in front of the longitudinal hole 55 in the longitudinal direction. The mounting hole 56 is a rectangular hole having a rectangular shape and penetrates in the width direction. As shown in FIGS. 4 and 6, the hook portion 42 of the support bracket 34 is inserted inside the mounting hole 56 to enable displacement of the telescopic friction plate 53 in the width direction. Thereby, the telescopic friction plate 53 is supported to enable only relative displacement in the width direction with respect to the support bracket 34 (inner column 26). When adjusting the front-rear position of the steering wheel 2, the telescopic friction plate 53 is displaced in the front-rear direction together with the inner column 26.

[0077] In this example, since the engaging portion 42 has a quadrangular prism shape (a rectangular parallelepiped shape) and the mounting hole 56 is a rectangular hole, the engaging portion 42 is inserted into the mounting hole 56 in a substantially non-rotatable manner relative to the mounting hole 56.

[0078] In this example, on the outer peripheral surface of the tip portion (the end portion on the outer side in the width direction) of each of the two engaging portions 42 provided on the support bracket 34, a limiting protrusion 57 is provided for restricting the movement of the telescopic friction plate 53 in the width direction with respect to the engaging portion 42. Specifically, the limiting protrusion 57 is provided in a flange shape on the front half of the upper surface of the tip portion of the engaging portion 42, and protrudes upward in a direction perpendicular to each of the long holes 55 in the width direction and the front-rear direction. The limiting protrusion 57 is composed of a thin plate having a substantially rectangular shape when viewed in the width direction. The limiting protrusion 57 is provided integrally with the engaging portion 42. As shown in FIG. 6, the inner surface of the limiting protrusion 57 faces the portion of the outer surface of the telescopic friction plate 53 located above the mounting hole 56 and located on the outermost side in the width direction in the width direction. The protruding amount of the limiting protrusion 57 is smaller than the vertical dimension of the portion of the telescopic friction plate 53 located above the mounting hole 56.

[0079] The engaging portion 42 has a relief recess 58 recessed inward in the width direction in the lower portion of the tip surface, which is opposite to the upper portion where the limiting protrusion 57 is provided. The relief recess 58 prevents the lower edge of the mounting hole 56 from abutting against the tip surface of the engaging portion 42 when the telescopic friction plate 53 is assembled to the engaging portion 42.

[0080] To assemble the telescopic friction plate 53 to the hooking portion 42 (insert the hooking portion 42 inside the mounting hole 56), first, as shown in Fig. 12(A), with the telescopic friction plate 53 tilted such that the upper side is positioned more inward in the width direction than the lower side, hook (engage) the upper edge of the mounting hole 56 from the inner side in the width direction with respect to the restricting projection 57 of the hooking portion 42. Next, as shown in Fig. 12(B), while rotating the telescopic friction plate 53 in the direction in which the inclination angle decreases, insert the hooking portion 42 inside the mounting hole 56. In this example, since the hooking portion 42 is provided with a relief recess 58, it is possible to prevent the lower edge of the mounting hole 56 of the telescopic friction plate 53 from coming into contact with the front end surface of the hooking portion 42.

[0081] In this example, the fixed-side friction plate 54 is made of a metal plate such as a steel plate having a large coefficient of friction with respect to the side surface of the telescopic friction plate 53 and has a circular hole 59 penetrating in the width direction. The adjustment rod 21 is inserted in the width direction through the circular hole 59 provided in the fixed-side friction plate 54. In this example, the fixed-side friction plate 54 arranged on one side in the width direction and the fixed-side friction plate 54 arranged on the other side in the width direction are connected in the width direction by a connecting portion 60 at their respective lower ends. Such a fixed-side friction plate 54 is displaced in synchronization with the adjustment rod 21 when adjusting the vertical position and the front-rear position of the steering wheel 2. That is, when adjusting the vertical position of the steering wheel 2, the fixed-side friction plate 54 is displaced vertically together with the adjustment rod 21, and when adjusting the front-rear position of the steering wheel 2, it stays in the same position.

[0082] In the steering column device 4 of this example, in order to mitigate the impact load applied to the driver's body in the event of a secondary collision, it is provided with a shock absorption mechanism that allows the steering wheel 2 to be displaced forward. In this example, as shown in FIGS. 2 and 4, the support bracket 34 that supports the front end portion of the telescopic friction plate 53 is attached to the inner column 26 by a shear pin 39. When a strong forward force is applied to the support bracket 34 from the steering wheel 2 via the outer shaft 18 and the inner column 26 with the occurrence of a secondary collision, the shear pin 39 breaks. As a result, the forward displacement of the inner column 26, the outer shaft 18 supported by the inner column 26, and the steering wheel 2 is allowed, and the impact load applied to the driver's body is mitigated.

[0083] In the steering column device 4 of this example, when adjusting the position of the steering wheel 2, by swinging the adjustment lever 22, the movable side cam 50 is rotated in the unlocking direction, the width direction dimension of the cam device 23 is reduced, and the distance between the fixed side cam 51 and the thrust bearing 24 is increased. As a result, the force for sandwiching the pair of sandwiched plate portions 30a, 30b from both sides in the width direction by the pair of support plate portions 43a, 43b decreases or is lost. At the same time, the inner diameter of the outer column 25 elastically expands, and the surface pressure of the contact portion between the inner peripheral surface of the outer column 25 and the outer peripheral surface of the front side portion of the inner column 26 decreases. In such an unclamped state, the vertical position of the steering wheel 2 can be adjusted within the range where the adjustment rod 21 can move inside the vehicle body side through holes 45a, 45b. Also, the steering wheel 2 can be adjusted in the front-rear position within the range between the front end position where the cushioning material 41 of the support bracket 34 supported by the inner column 26 abuts against the front end edge 28a of the slit 28 and the rear end position where the stopper member 35 abuts against the abutting surface 32a of the bulging portion 32.

[0084] After moving the steering wheel 2 to a desired position, by swinging the adjustment lever 22, the movable-side cam 50 is rotated in the locking direction, the widthwise dimension of the cam device 23 is increased, and the distance between the fixed-side cam 51 and the thrust bearing 24 is reduced. As a result, the force with which the pair of support plate portions 43a, 43b sandwich the pair of sandwiched plate portions 30a, 30b from both sides in the width direction increases, and at the same time, the inner diameter of the outer column 25 elastically contracts, and the surface pressure of the contact portion between the inner peripheral surface of the outer column 25 and the outer peripheral surface of the front side portion of the inner column 26 increases. As a result, the steering wheel 2 is held at the adjusted position.

[0085] According to the steering column device 4 of this example, the movement of the telescopic friction plate 53 in the width direction with respect to the engaging portion 42 is restricted.

[0086] That is, in this example, the engaging portion 42 having a cantilever structure is provided with a restricting projection 57 on the outer peripheral surface of its tip end portion for restricting the movement of the telescopic friction plate 53 in the width direction with respect to the engaging portion 42. For this reason, when the cam device 23 is unclamped, even if there is a bend such that the outer surface of the telescopic friction plate 53 disposed on one side in the width direction (the upper side in FIG. 11) among the telescopic friction plates 53 disposed most outward in the width direction is concave, the restricting projection 57 and the portion of the telescopic friction plate 53 located above the mounting hole 56 engage with each other, thereby preventing the telescopic friction plate 53 from moving further in the width direction with respect to the engaging portion 42. As a result, it is possible to prevent the engagement margin of the telescopic friction plate 53 disposed on one side in the width direction with respect to the engaging portion 42 from becoming smaller. In this example, since the restricting projection 57 is provided on both of the pair of engaging portions 42 on both sides in the width direction, the movement of the telescopic friction plate 53 disposed on the other side in the width direction in the width direction with respect to the engaging portion 42 is also restricted.

[0087] In this example, the limiting projection 57 is provided so as to project upward in a direction perpendicular to each of the width-direction and longitudinal slots 55. For this reason, when the telescopic friction plate 53 is supported (assembled) by the engaging portion 42, instead of tilting the telescopic friction plate 53 in the longitudinal direction with larger dimensions in the width direction (for example, tilting the front side portion to be located more inward in the width direction than the rear side portion), it can be performed by tilting the upper and lower sides with shorter dimensions in the width direction (tilting the upper side portion to be located more inward in the width direction than the lower side portion). Therefore, it is possible to improve the workability in the assembly thereof.

[0088] In this example, the limiting projection 57 is integrally provided on the outer peripheral surface of the tip of the engaging portion 42, and the engaging portion 42 is provided on the support bracket 34 that detaches from the inner column 26 when a secondary collision occurs. For this reason, an increase in the number of parts of the steering column device 4 can be suppressed, and the steering column device 4 can be made more compact. Thereby, it is also possible to improve the layout property of the steering device to which the steering column device 4 is assembled.

[0089] In this example, as shown in FIG. 11, the plurality of telescopic friction plates 53 arranged on one side in the width direction are arranged in a curved state such that their outer surfaces are concave surfaces in a free state, and the plurality of telescopic friction plates 53 arranged on the other side in the width direction are arranged in a curved state such that their outer surfaces are convex surfaces. For this reason, as a modification of this example, among the pair of engaging portions 42 provided on the support bracket 34, the limiting projection 57 can be provided only on the engaging portion 42 arranged on one side in the width direction where the engagement margin of the telescopic friction plate is likely to be small. Further, as another modification, the limiting projection can be provided on the lower surface of the tip of the engaging portion so as to project downward.

[0090] [Second Example] A second example of the embodiment of the present invention will be described with reference to FIG. 13.

[0091] In this example, a limiting protrusion 57a is provided on the front side surface of the tip of the hooking portion 42a. The limiting protrusion 57a protrudes in the forward direction, which is the extending direction of the longitudinal slot 55 in the front-rear direction. The limiting protrusion 57a is composed of a thin plate having a substantially rectangular shape when viewed in the width direction. The inner surface of the limiting protrusion 57a faces, in the width direction, a portion of the outer surface of the telescopic friction plate 53 that is located on the outermost side in the width direction among the plurality of telescopic friction plates 53 and that is located in front of the mounting hole 56. The protruding amount of the limiting protrusion 57a is smaller than the front-rear dimension of the portion of the telescopic friction plate 53 that is located in front of the mounting hole 56.

[0092] The hooking portion 42a has a relief recess 58a that is recessed inward in the width direction on the rear side portion of the tip surface that is opposite to the front side portion where the limiting protrusion 57a is provided. The relief recess 58a prevents the rear edge of the mounting hole 56 of the telescopic friction plate 53 from contacting the tip surface of the hooking portion 42a when the telescopic friction plate 53 is assembled to the hooking portion 42a.

[0093] To insert the hooking portion 42a inside the mounting hole 56 of the telescopic friction plate 53, first, with the telescopic friction plate 53 tilted so that the front side portion is located more inward in the width direction than the rear side portion, the front edge portion of the mounting hole 56 is hooked (locked) from the inside in the width direction with respect to the limiting protrusion 57a of the hooking portion 42a. Next, while rotating the telescopic friction plate 53 in a direction in which the tilt angle becomes smaller, the hooking portion 42a is inserted inside the mounting hole 56.

[0094] Also in the case of this example, the hooking portion 42a the movement of the telescopic friction plate 53 in the width direction with respect to is restricted. Regarding other configurations and operational effects, they are the same as those in the first example.

[0095] As described above, the embodiments of the present invention have been explained, but the present invention is not limited to this, and can be appropriately changed without departing from the technical idea of the invention. Also, the structures of each example of the embodiments can be implemented in appropriate combination as long as no contradiction occurs.

[0096] When implementing the present invention, the shape, formation position, formation range, etc. of the restriction protrusion are not limited to the structures shown in each example of the embodiments, and can be appropriately changed as long as they can exhibit the function of restricting the movement of the friction plate in the width direction. Also, the shape of the engaging portion is not limited to the structures shown in each example of the embodiments, and shapes other than a square prism (rectangular prism), such as a cylindrical shape, can be adopted. Further, the elongated holes (for example, longitudinal holes in the front-rear direction, longitudinal holes in the up-down direction) provided in the friction plate and extending in the direction in which the position of the steering wheel can be adjusted are not limited to the slit-shaped elongated holes as shown in each example of the embodiments, and can also be constituted by elongated holes having a shape with a closed periphery. Furthermore, the steering column device of the present invention can be applied not only to a telescopic friction plate but also to restricting the movement of a tilt friction plate in the width direction.

Explanation of Signs

[0097] 1 Electric power steering device 2 Steering wheel 3 Steering shaft 4 Steering column device 5a, 5b Universal joint 6 Intermediate shaft 7 Steering gear unit 8 Tie rod 9 Electric assist device 10 Gear housing 11 Torsion bar 12 Output shaft 13 Pinion shaft 14 Torque sensor 15 Electric motor 16 Worm reducer 17 Inner shaft 18 Outer shaft 19 Steering column 20 Vehicle body side bracket 21 Adjusting rod 22 Adjusting lever 23 Cam device 24 Thrust bearing 25 Outer column 26 Inner Column 27 Rolling Bearing 28 Slit 28a Front Edge 29 Column Side Bracket 30a, 30b Clamped Plate Parts 31a, 31b Column Side Through-Holes 32 Bulge 32a Contact Surface 33 Accommodation Space 34 Support Bracket 35 Stopper Member 36 Mounting Part 36a Through-Hole 37 Connection Part 38 Body Part 39 Split Pin 40 Locking Recess 41 Buffer Material 42, 42a Hooking Parts 43a, 43b Support Plate Parts 44 Top Plate Part 45a, 45b Vehicle Body Side Through-Holes 46 Through-Hole 47 Anchor Part 48 Male Thread Part 49 Nut 50 Movable Side Cam 51 Fixed Side Cam 52 Friction Unit 53 Telescopic Friction Plate 54 Fixed Side Friction Plate 55 Longitudinal Slot 56 Mounting Hole 57, 57a Limiting Protrusions 58 Relief Recess 59 Circular Hole 60 Connecting Part 100 Steering Shaft 101 Steering Column 102 Inner Shaft 103 Outer Shaft 104 Inner Column 105 Outer Column 106 Clamped Plate Part 107 Column Side Bracket 108 Body side bracket 109 Support plate part 110 Column side through hole 111 Body side through hole 112 Adjustment rod 113 Anchor part 114 Retaining member 115 Cam device 116 Adjustment lever 117 Movable side cam 118 Fixed side cam 119 Friction unit 120 Telescopic friction plate 121 Washer 122 Long hole in the front - rear direction 123 Mounting hole 124 Hooking part

Claims

1. A steering column provided with a column-side bracket having a column-side through-hole penetrating in the width direction, A vehicle-body-side bracket provided with a pair of support plate portions disposed on both sides in the width direction of the column-side bracket, each having a vehicle-body-side through-hole penetrating in the width direction, An adjustment rod inserted through the column-side through-hole and the pair of vehicle-body-side through-holes in the width direction, A pair of pressing portions provided at portions of the adjustment rod protruding in the width direction from the outer surfaces of the pair of support plate portions, A telescoping mechanism for expanding and contracting the distance between the pair of pressing portions, Extending in a direction in which the position of the steering wheel can be adjusted, having a long hole through which the adjustment rod is inserted and a mounting hole, and being sandwiched at least in part between a portion between an inner surface of one of the pair of support plate portions and an outer surface of the column-side bracket and a portion between an outer surface of one of the pair of support plate portions and an inner surface of one of the pair of pressing portions, a friction plate, A hooking portion having a cantilever structure and inserting the mounting hole in the width direction, and comprising The hooking portion has a limiting protrusion for restricting the movement of the friction plate in the width direction, A steering column device.

2. The steering column device according to claim 1, wherein the limiting protrusion protrudes in a direction perpendicular to each of the width direction and the extending direction of the long hole.

3. The steering column device according to any one of claims 1 to 2, wherein the limiting protrusion is integrally provided on the outer peripheral surface of the end portion of the hooking portion.

4. The steering column device according to any one of claims 1 to 3, wherein the hooking portion is inserted into the mounting hole in a substantially non-rotatable manner relative to the mounting hole.

5. The steering column device according to any one of claims 1 to 4, wherein the friction plate is curved in a free state such that its outer surface is a concave surface.

6. The steering column has an outer column disposed on the front side, an inner column disposed on the rear side, and a support bracket. The outer column includes a slit extending in the axial direction, and a pair of sandwiched plate portions that are disposed on both sides in the width direction of the slit and each have a column-side through hole formed therein, and constitute the column-side bracket. The support bracket includes a mounting portion disposed inside the slit and detachably attached to the inner column, and the hook portion. The long hole is a longitudinally extending long hole extending in the front-rear direction. The steering column device according to any one of claims 1 to 5.

7. The friction plate is sandwiched one or more at a time between the inner surfaces of the pair of support plate portions and the outer surfaces of the pair of sandwiched plate portions. The support bracket includes two of the hook portions. The limiting protrusion is provided on at least one of the two hook portions. The steering column device according to claim 6.

8. The steering column device according to claim 7, wherein the limiting protrusion is provided on both of the two hook portions.

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