Steering device

Abstract

To provide a steering device that can change the amount of forward displacement of an upper column to a lower column without using an impact absorption member.SOLUTION: A steering device includes: a steering column 2 provided with a lower column 10 and an upper column 11; a switching lever 3 capable of switching between a locked state and a lock released state; a restriction engagement portion 4 insertable and retractable with respect to a restriction elongated hole 20 disposed in the upper column 11; a restriction release preload spring 5 configured to apply elastic force to the restriction engagement portion 4 so as to separate the restriction engagement portion from the restriction elongated hole 20; and a restriction cam member 6 rotatable with the switching lever 3. The restriction cam member 6 includes a restriction cam surface 42 adapted to press the restriction engagement portion 4 in a direction toward the restriction elongated hole 20.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a steering device that allows the longitudinal position of a steering wheel to be adjusted. [Background technology]

[0002] FIG. 16 shows an example of a steering device for an automobile. In the steering device 100, a steering wheel 101 operated by a driver is attached to the rear end of a steering shaft 102. The steering shaft 102 is rotatably supported inside a steering column 103 supported on the vehicle body. The rotational motion of the steering wheel 101 is transmitted to a pinion shaft 107 that constitutes a steering gear unit 106 via the steering shaft 102, a universal joint 104a, an intermediate shaft 105, and another universal joint 104b. The rotational motion of the pinion shaft 107 is converted into linear motion of a rack shaft (not shown) that constitutes the steering gear unit 106. This pushes and pulls a pair of tie rods 108, and a steering angle is applied to the left and right steered wheels according to the amount of operation of the steering wheel 101.

[0003] Steering devices typically have a telescopic adjustment function for adjusting the fore-and-aft position of the steering wheel according to the driver's physique and driving posture, and an impact absorption function for mitigating the impact load applied to the driver's body in the event of a secondary collision.

[0004] Specifically, to ensure telescopic adjustment function, the steering shaft includes an upper shaft disposed at the rear and a lower shaft disposed at the front, which are combined to allow relative axial displacement and torque transmission, and the overall length can be extended or retracted by relatively displacing the upper shaft and the lower shaft in the axial direction. The steering column includes an upper column disposed at the rear and a lower column disposed at the front, which are combined to allow relative axial displacement, and the overall length can be extended or retracted by relatively displacing the upper column and the lower column in the axial direction. The lower shaft is supported inside the lower column so as to be capable of rotation only. The upper shaft is supported inside the upper column so as to be capable of rotation only. The steering wheel is attached to the rear end of the upper shaft. When adjusting the fore-and-aft position of the steering wheel, the steering wheel, the upper shaft, and the upper column are displaced axially, i.e., in the fore-and-aft direction, relative to the lower shaft and the lower column.

[0005] To ensure impact absorption, the steering device is provided with an impact absorption structure, for example, between the lower column and the upper column. During a collision, following a primary collision in which the vehicle collides with another vehicle, a secondary collision occurs in which the driver's body collides with the steering wheel. When a strong forward impact load is applied to the steering wheel, upper shaft, and upper column, the impact load is absorbed by the impact absorption structure as the upper column displaces forward relative to the lower column. This reduces the impact on the driver's body when they collide with the steering wheel.

[0006] When a secondary collision occurs, it is necessary to increase the amount by which the upper column can be displaced forward relative to the lower column compared to normal times, i.e., when the fore-and-aft position of the steering wheel is adjusted.

[0007] A structure for switching the amount by which the upper column can be displaced forward relative to the lower column is described in, for example, Japanese Patent No. 6661447.

[0008] The structure disclosed in Japanese Patent No. 6661447 includes a switching lever, a restricting elongated hole, an impact absorbing leaf spring, and a restricting engagement element. The switching lever is supported by the lower column so as to be rotatable about a pivot axis in the width direction, and is switchable between a locked state that disables adjustment of the fore-aft position of the steering wheel and an unlocked state that enables such adjustment, by changing the rotational position about the pivot axis. The restricting elongated hole is provided in the upper column and extends in the axial direction of the upper column. The impact absorbing leaf spring swings in conjunction with rotation of the switching lever. The restricting engagement element is fixed to the tip of the impact absorbing leaf spring and moves toward or away from the restricting elongated hole in conjunction with swing of the impact absorbing leaf spring in conjunction with rotation of the switching lever.

[0009] The restricting engagement element enters the restricting elongated hole as the switching lever rotates from a rotation position in the locked state to a rotation position in the unlocked state. In this state, i.e., the unlocked state in which the fore-aft position of the steering wheel can be adjusted, the upper column can be displaced in the axial direction relative to the lower column only to the extent that the restricting engagement element can move axially inside the restricting elongated hole.

[0010] The restricting engagement element comes out of the restricting elongated hole as the switching lever rotates from the unlocked rotation position to the locked rotation position. Therefore, in this state, i.e., in the locked state in which the fore-aft position of the steering wheel cannot be adjusted, a greater amount of forward displacement of the upper column relative to the lower column can be ensured in the event of a secondary collision. Furthermore, with this structure, in the event of a secondary collision, a frictional load is generated between the base end of the impact absorbing leaf spring and a portion of the upper column, and this frictional load absorbs the impact load. The contents of Japanese Patent No. 6661447 are incorporated herein by reference. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Patent No. 6661447 Summary of the Invention [Problem to be solved by the invention]

[0012] In the structure described in Japanese Patent No. 6661447, the restricting engagement element is fixed to the tip of the impact absorbing leaf spring. Therefore, when adjusting the fore-aft position of the steering wheel in the unlocked state, if the front or rear end of the restricting elongated hole hits the restricting engagement element with force, the impact absorbing leaf spring may be deformed. If the impact absorbing leaf spring is deformed, the impact absorbing performance may become unstable in the event of a secondary collision.

[0013] An object of the present invention is to provide a steering device that is capable of switching the amount by which an upper column can be displaced forward relative to a lower column without using an impact absorbing member. [Means for solving the problem]

[0014] A steering device according to one aspect of the present invention includes a steering column, a switching lever, a restricting engagement element, a restricting release preload spring, and a restricting cam member.

[0015] The steering column has a lower column, an upper column combined with the lower column so as to be able to move axially relative to the lower column, and a restricting elongated hole that is provided on the upper column directly or via another member and extends in the axial direction of the upper column.

[0016] The switching lever is supported by the lower column so as to be rotatable about a widthwise rotation center axis, and is switchable between a locked state in which the fore-aft position of the steering wheel cannot be adjusted and an unlocked state in which such adjustment is possible, based on changing the rotation position about the rotation center axis.

[0017] The restricting engagement element is supported on the lower column so as to be able to move toward and away from the restricting long hole, and is capable of entering the restricting long hole when it approaches the restricting long hole, and of coming out of the restricting long hole when it moves away from the restricting long hole.

[0018] The restriction release preload spring applies a resilient force to the restriction engaging element in a direction away from the restriction elongated hole.

[0019] The restricting cam member rotates together with the switching lever around the rotation central axis. The restricting cam member has a restricting cam surface that pushes the restricting engagement element in a direction toward the restricting elongated hole. The restricting cam surface is an inclined surface whose position in the direction toward or away from the restricting elongated hole and the restricting engagement element changes along the circumferential direction of the rotation central axis. Specifically, on the restricting cam surface, a portion that pushes the restricting engagement element when the switching lever is in the rotation position for the unlocked state is located closer to the restricting elongated hole than a portion that pushes the restricting engagement element when the switching lever is in the rotation position for the locked state.

[0020] As the switching lever rotates from the rotation position in the locked state to the rotation position in the unlocked state, the regulating engagement element is pushed by the regulating cam surface to move to a position where it enters the regulating long hole, and as the switching lever rotates from the rotation position in the unlocked state to the rotation position in the locked state, the regulating engagement element is pushed by the elastic force of the regulating release preload spring to move to a position where it comes out of the regulating long hole.

[0021] A steering device according to one aspect of the present invention includes: a fixed gear that is provided on the upper column directly or via another member and extends in the axial direction; and a locking engager having a movable gear that is supported on the lower column so as to be movable toward and away from the fixed gear, and that meshes with the fixed gear as it approaches the fixed gear and disengages from the fixed gear as it moves away from the fixed gear. As the switch lever rotates from a rotation position in the locked state to a rotation position in the unlocked state, the locking engager moves away from the fixed gear to a position where the meshing between the fixed gear and the movable gear is released, and as the switch lever rotates from the rotation position in the unlocked state to the rotation position in the locked state, the locking engager moves toward a position where the fixed gear and the movable gear mesh.

[0022] A steering device according to one aspect of the present invention includes an unlocking preload spring that applies elastic force to the locking engager in a direction away from the fixed-side gear, and a locking cam member that rotates together with the switching lever about the central axis of rotation. The locking cam member has a locking cam surface that presses the locking engager in a direction toward the fixed-side gear. The locking cam surface is an inclined surface whose position in the direction toward or away from the fixed-side gear changes along the circumferential direction of the central axis of rotation. Specifically, on the locking cam surface, a portion that presses the locking engager when the switching lever is in the rotational position for the locked state is located closer to the fixed-side gear than a portion that presses the locking engager when the switching lever is in the rotational position for the unlocked state. As the switching lever rotates from the rotation position in the locked state to the rotation position in the unlocked state, the locking engagement element is pushed by the elastic force of the unlocking preload spring and moves to a position where the meshing between the fixed side gear and the movable side gear is released, and as the switching lever rotates from the rotation position in the unlocked state to the rotation position in the locked state, the locking engagement element is pushed by the locking cam surface and moves to a position where the fixed side gear and the movable side gear mesh. [Effects of the Invention]

[0023] According to the steering device of one aspect of the present invention, it is possible to switch the amount by which the upper column can be displaced forward relative to the lower column without using an impact absorbing member. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 is a side view showing a steering device according to an embodiment of the present invention in a locked state in which the longitudinal position of the steering wheel cannot be adjusted. [Figure 2] FIG. 2 is a view of FIG. 1 as seen from above. [Figure 3] FIG. 3 is a view from below of FIG. [Figure 4] FIG. 4 is a view from the right side of FIG. [Figure 5] FIG. 5 is an enlarged view of the middle part in the left-right direction of FIG. [Figure 6] FIG. 6 is an enlarged view of the middle part in the left-right direction of FIG. 3 (viewed from below in FIG. 5). [Figure 7] FIG. 7 is a cross-sectional view taken along line AA in FIG. [Figure 8] FIG. 8 is a view seen from the opposite side of FIG. [Figure 9] FIG. 9 is a view corresponding to FIG. 5, showing the steering device in an unlocked state that allows adjustment of the fore-and-aft position of the steering wheel. [Figure 10] FIG. 10 is a view from below of FIG. [Figure 11] FIG. 11 is a cross-sectional view taken along the line BB in FIG. [Figure 12] FIG. 12 is a view seen from the opposite side of FIG. [Figure 13] FIG. 13 is an exploded perspective view of a part of the steering device as seen from the rear and upper left. [Figure 14] FIG. 14 is an exploded perspective view of a part of the steering device as seen from the rear and upper right. [Figure 15]FIG. 15(a) is a perspective view of a lower column that constitutes the steering device, as seen from the rear and upper left, and FIG. 15(b) is a perspective view of the lower column as seen from the rear and upper right. [Figure 16] FIG. 16 is a perspective view showing an example of a conventional structure of a steering device. DETAILED DESCRIPTION OF THE INVENTION

[0025] An embodiment of the present invention will be described with reference to FIGS. 1 to 15. FIG.

[0026] The steering device 1 of this example includes a steering column 2, a switching lever 3, a restricting engagement element 4, a restricting release preload spring 5, and a restricting cam member 6.

[0027] The front-rear direction, width direction, and up-down direction of the steering device 1 refer to the front-rear direction, width direction, and up-down direction of the vehicle body to which the steering device 1 is attached. The front side is the left side in Figures 1 to 3, 5, 6, 9, and 10, and the right side in Figures 8 and 12. The rear side is the right side in Figures 1 to 3, 5, 6, 9, and 10, and the left side in Figures 8 and 12.

[0028] The steering device 1 of this example is equipped with a switching mechanism 7 for switching between a locked state in which the fore-aft and height positions of a steering wheel (not shown) operated by a driver cannot be adjusted, and an unlocked state in which such adjustment is possible. The switching lever 3 constitutes a part of the switching mechanism 7. Figures 1 to 8 show the steering device 1 in the locked state. Figures 9 to 12 show the steering device 1 in the unlocked state.

[0029] In the steering device 1 of this example, a steering shaft 8 is rotatably supported inside the steering column 2. An axially intermediate portion of the steering column 2 is supported on the vehicle body using a support bracket 9. The steering wheel is attached to the rear end of the steering shaft 8, which protrudes rearward beyond the rear end of the steering column 2.

[0030] The steering column 2 combines a lower column 10 located on the front side and an upper column 11 located on the rear side so that they can be displaced relative to each other in the axial direction. In this example, the lower column 10 is an outer column located on the radially outer side, and the upper column 11 is an inner column located on the radially inner side. However, when implementing the present invention, it is also possible for the lower column to be the inner column and the upper column to be the outer column.

[0031] In this example, the lower column 10 is made of a metal such as steel or an aluminum alloy and has a substantially cylindrical shape. As shown in FIGS. 13 to 15(b), the lower column 10 has a slit 12 at its upper end, which is a circumferential portion, that extends from an intermediate portion in the axial direction to the rear end. The inner diameter of the lower column 10 is expandable and contractible by elastically expanding and contracting the width of the slit 12. At the rear end, the lower column 10 has flange portions 13 that protrude radially outward (upward) at two locations that sandwich the slit 12 from both sides in the width direction. Each of the flange portions 13 has through-holes 14 that penetrate in the width direction at locations that align with each other in the width direction.

[0032] The lower column 10 has a recessed portion 15 that recesses radially outward and extends in the axial direction at an end portion on one width direction side (the left side in FIGS. 4, 7, and 11) that is a circumferential portion of the inner circumferential surface of a portion ranging from an intermediate portion in the axial direction to the rear end portion. The lower column 10 has a one-side through-hole 16 that penetrates in the width direction at an end portion on one width direction side of the axial rear side portion and whose end portion on the inner side in the width direction opens into the recessed portion 15. The one-side through-hole 16 is a non-circular hole, and a portion of the circumferential direction of the inner circumferential surface is configured by a flat surface, and the remaining circumferential portion of the inner circumferential surface is configured by a cylindrical surface. The lower column 10 has a other-side through-hole 17 that penetrates in the width direction at an end portion on the other width direction side of the axial rear side portion (the right side in FIGS. 4, 7, and 11). The other-side through-hole 17 is a circular hole. In the illustrated example, the one-side through-hole 16 and the other-side through-hole 17 are disposed in front of the through-hole 14 in the axial direction of the lower column 10 and at positions aligned with each other in the width direction.

[0033] The lower column 10 has a widthwise insertion hole 18 at the top of the front end portion. A widthwise tilt shaft 19 (see FIG. 1) supported by the vehicle body is inserted into the insertion hole 18. As a result, the lower column 10 is supported not only under normal circumstances but also in the event of a secondary collision so as not to be displaced forward relative to the vehicle body and so as to be capable of swinging displacement about the tilt shaft 19 relative to the vehicle body.

[0034] In this example, the upper column 11 is cylindrical and made of metal such as steel, aluminum alloy, etc. The front portion of the upper column 11 is fitted into the rear portion of the lower column 10 so as to allow relative displacement in the axial direction.

[0035] As shown in FIG. 14 , the upper column 11 has a restriction elongated hole 20 extending in the axial direction. In this example, the restriction elongated hole 20 is configured as a through-hole extending in the axial direction, provided at the end portion on the other widthwise side, which is a circumferential portion of the axial front side of the upper column 11. With the front side of the upper column 11 fitted into the rear side of the lower column 10, part of the extension direction of the restriction elongated hole 20 faces the other-side through-hole 17 of the lower column 10 in the widthwise direction. When practicing the present invention, the restriction elongated hole can also be configured as a bottomed hole that opens only radially outward and extends in the axial direction. Also, in this example, the restriction elongated hole 20 is provided directly in the upper column 11, but when practicing the present invention, the restriction elongated hole can also be provided in the upper column via another member, that is, the restriction elongated hole can be provided in another member fixed to the upper column.

[0036] The steering shaft 8 includes a lower shaft 21 disposed on the front side and an upper shaft 22 disposed on the rear side. The lower shaft 21 and the upper shaft 22 are spline-fitted to enable torque transmission and relative axial displacement.

[0037] The lower shaft 21 is supported relative to the lower column 10 so as to be capable of only rotation by a rolling bearing (not shown) that is fitted into the front end of the lower column 10. The front end of the lower shaft 21, which protrudes forward beyond the front end of the lower column 10, is connected to the rear end of an intermediate shaft (not shown) via a universal joint (not shown).

[0038] The upper shaft 22 is supported by the upper column 11 so as to be capable of only rotation by a rolling bearing 23 (see FIG. 4) that is fitted into the rear end of the upper column 11. A steering wheel is attached to the rear end of the upper shaft 22, which protrudes rearward beyond the rear end of the upper column 11.

[0039] The support bracket 9 is made of a metal such as steel and includes a mounting plate portion 24 and two support plate portions 25a, 25b. The mounting plate portion 24 forms the upper side of the support bracket 9 and is arranged in the width direction. The mounting plate portion 24 is supported on the vehicle body. The two support plate portions 25a, 25b are arranged substantially parallel to each other in positions sandwiching the rear side portion of the lower column 10 from both sides in the width direction. The upper end portion of each of the support plate portions 25a, 25b is joined and fixed to a widthwise intermediate portion of the mounting plate portion 24. The support plate portions 25a, 25b are aligned with each other in the width direction and have tilt elongated holes 26 that extend in the up-down direction at locations that align with the through-holes 14 of the flange portion 13. Each of the tilt elongated holes 26 has an arc shape centered on the tilt axis 19.

[0040] The switching lever 3 constitutes a part of a switching mechanism 7 (see FIGS. 5 and 7). In addition to the switching lever 3, the switching mechanism 7 includes a switching rod 27, a nut 28, a cam device 29, and a thrust bearing 30.

[0041] The switching rod 27 is inserted widthwise through the tilt slot 26 and the through-hole 14. The switching rod 27 has a head 31 at its base end (the left end in FIGS. 4 and 7) and a male thread 32 at its tip end (the right end in FIGS. 4 and 7).

[0042] The nut 28 is threaded onto the male thread portion 32 .

[0043] The cam device 29 is disposed between the head portion 31 and one of the support plate portions 25a (the left side in FIGS. 4 and 7). The cam device 29 has a drive cam 33 located on the outer side in the width direction and a driven cam 34 located on the inner side in the width direction. The driven cam 34 is engaged with the tilt elongated hole 26 of one of the support plate portions 25a so as to be unable to rotate relative to it. The driven cam 34 is fitted onto the switching rod 27 so as to be able to rotate and move in the axial direction. The drive cam 33 is fitted onto the switching rod 27 so as to be unable to rotate and move in the axial direction.

[0044] The switching lever 3 is supported by the lower column 10 so as to be rotatable about a rotation center axis in the width direction. In this example, the base end of the switching lever 3 is fixed to the drive cam 33. That is, the switching lever 3 is supported by the base end of the switching rod 27 via the drive cam 33 so as to be rotatable about the central axis of the switching rod 27. In this example, the central axis of the switching rod 27 corresponds to the rotation center axis in the width direction.

[0045] The switching lever 3 is a member for switching between a locked state, which disables adjustment of the fore-aft and height positions of the steering wheel, and an unlocked state, which allows such adjustment, by changing the rotational position around the central axis of the switching rod 27.

[0046] In this example, when the switching lever 3, the driving cam 33, and the switching rod 27 are rotated synchronously around the central axis of the switching rod 27, the driving cam 33 and the driven cam 34 are rotated relative to each other, and the opposing side surfaces (cam surfaces) of the driving cam 33 and the driven cam 34 press against each other, causing the axial dimension of the cam device 29 to expand and contract. In this example, when the switching lever 3 is rotated downward from the rotation position in the locked state shown in FIG. 5 to the rotation position in the unlocked state shown in FIG. 9, the axial dimension of the cam device 29 decreases. Conversely, when the switching lever 3 is rotated upward from the rotation position in the unlocked state shown in FIG. 9 to the rotation position in the locked state shown in FIG. 5, the axial dimension of the cam device 29 increases.

[0047] The thrust bearing 30 is disposed between the nut 28 and the other (right side in FIGS. 4 and 7) support plate portion 25b.

[0048] The restricting engagement element 4 is supported on the lower column 10 so as to be able to move toward and away from the restricting elongated hole 20, and can enter the restricting elongated hole 20 when it approaches the restricting elongated hole 20, and can come out of the restricting elongated hole 20 when it moves away from the restricting elongated hole 20.

[0049] When implementing the present invention, a structure can be adopted in which the restricting engaging element includes a restricting supported portion that is supported on a restricting support portion that is provided on the lower column directly or via another member so as to be movable toward and away from the restricting through-hole, a restricting engaging portion that can enter and exit the restricting elongated hole, a restricting release elastic force receiving portion that is imparted with an elastic force in a direction away from the restricting elongated hole by a restricting release preload spring, and a restricting cam force receiving portion that is pressed by a restricting cam surface in a direction toward the restricting elongated hole by a restricting cam surface directly or via another member. When implementing the present invention, any shape can be adopted for each of these portions. In this example, the restricting engaging element 4 is configured as a stepped columnar shape as a whole. That is, the restricting engaging element 4 has a circular flange 35 protruding radially outward from a portion near the base end, and also has a cylindrical base end shaft 36 located adjacent to the base end side (outside in the width direction) of the flange 35, a cylindrical intermediate shaft 37 located adjacent to the tip side (inside in the width direction) of the flange 35, and a cylindrical tip shaft 38 having an outer diameter smaller than that of the intermediate shaft 37 located adjacent to the tip side of the intermediate shaft 37. In this example, the other-side through-hole 17 corresponds to the restricting support portion, the intermediate shaft 37 corresponds to the restricting supported portion, the tip shaft 38 corresponds to the restricting engaging portion, the flange 35 corresponds to the restricting release elastic force receiving portion, and the base end shaft 36 corresponds to the restricting cam force receiving portion.

[0050] The restricting engaging element 4 is supported on the lower column 10 so as to be movable axially toward and away from the elongated restricting hole 20 in the width direction by fitting the intermediate shaft portion 37 into the other-side through-hole 17 of the lower column 10. In this example, the restricting engaging element 4 can be moved closer to the elongated restricting hole 20 in the width direction to cause the tip shaft portion 38 to enter the elongated restricting hole 20, and the restricting engaging element 4 can be moved away from the elongated restricting hole 20 in the width direction to cause the tip shaft portion 38 to be removed from the elongated restricting hole 20.

[0051] The release preload spring 5 applies a resilient force to the restricting engaging element 4 in a direction away from the restricting elongated hole 20. When implementing the present invention, a spring disposed between the restricting engaging element and the lower column or a member fixed to the lower column can be used as the release preload spring. In this example, the release preload spring 5 is configured as an annular coiled wave spring, and is elastically sandwiched between the portion of the outer circumferential surface of the lower column 10 surrounding the other-side through-hole 17 and the side surface on the tip side of the flange portion 35 of the restricting engaging element 4. As a result, the release preload spring 5 applies a resilient force to the restricting engaging element 4 in a direction away from the restricting elongated hole 20 in the width direction. When implementing the present invention, the release preload spring is not limited to a coiled wave spring, and various springs such as a coil spring or a leaf spring can be used as the release preload spring.

[0052] The regulating cam member 6 rotates together with the switching lever 3 around the central axis of the switching rod 27. In this example, the regulating cam member 6 is non-circularly fitted to a portion of the switching rod 27 near the tip so that the regulating cam member 6 is unable to rotate relative to the switching rod 27.

[0053] The restricting cam member 6 of this example is made as a whole from a metal plate and includes a base plate portion 39 that fits non-circularly into a portion of the switching rod 27 near the tip and is sandwiched between the thrust bearing 30 and the nut 28, a connecting plate portion 40 that bends at a substantially right angle from a circumferential portion of the outer periphery of the base plate portion 39 toward the outside in the width direction, and a cam plate portion 41 that bends at a substantially right angle from the outer end of the connecting plate portion 40 in the opposite direction to the base plate portion 39. Most of the cam plate portion 41, excluding the base end portion, has a substantially fan shape whose circumferential width increases toward the outside in the radial direction of the switching rod 27 (see FIG. 8). At least a portion of the cam plate portion 41 is positioned on the outside in the width direction of the restricting engaging element 4, regardless of the rotational position of the switching lever 3.

[0054] The restricting cam member 6 of this example has a restricting cam surface 42 on the inner widthwise surface of the cam plate portion 41, which pushes the restricting engagement element 4 in a direction to approach the restricting elongated hole 20, i.e., inward in the width direction. In this example, the restricting cam surface 42 pushes the restricting engagement element 4 inward in the width direction via a restricting backup spring 43.

[0055] The restricting cam surface 42 is an inclined surface whose position in the width direction, which is the direction in which the restricting elongated hole 20 and the restricting engaging element 4 approach each other, changes along the circumferential direction of the central axis of the switching rod 27. In the restricting cam surface 42, a portion (α2 portion in FIGS. 10 and 11 ) that presses the restricting engaging element 4 when the switching lever 3 is in the rotational position for the unlocked state is located at a widthwise position (upper side in FIGS. 6 and 10 , left side in FIGS. 7 and 11 ) closer to the restricting elongated hole 20 than a portion (α1 portion in FIGS. 6 and 7 ) that presses the restricting engaging element 4 when the switching lever 3 is in the rotational position for the locked state. When carrying out the present invention, the restricting cam member may have any overall shape as long as it has a restricting cam surface (inclined surface).

[0056] In this example, the restriction backup spring 43 is configured as a U-shaped leaf spring. A fitting hole 44 provided at one end of the restriction backup spring 43 located on the inner side in the width direction is press-fitted onto the base-end shaft portion 36 of the restriction engagement element 4, and a convex portion 45 provided at the other end located on the outer side in the width direction and protruding outward in the width direction is brought into contact with the restriction cam surface 42. In this state, the restriction backup spring 43 is elastically sandwiched between the side surface on the base end side of the flange portion 35 of the restriction engagement element 4 and the restriction cam surface 42. The spring constant of the restriction backup spring 43 is greater than the spring constant of the restriction release preload spring 5. Therefore, in the assembled state of the steering device 1 of this example, the amount of compression in the width direction of the restriction release preload spring 5 is greater than the amount of compression in the width direction of the restriction backup spring 43. When carrying out the present invention, the reserve regulating spring is not limited to a leaf spring, and various springs such as a disc spring can be used.

[0057] The steering device 1 of this example includes, as additional elements to the switching mechanism 7, a fixed-side gear 46, a locking engagement element 47, an unlocking preload spring 48, and a locking cam member 49.

[0058] In this example, the fixed-side gear 46 is formed on a gear plate 50 fixed to the upper column 11. The gear plate 50 is made of a metal plate such as a steel plate and is configured in the shape of a rectangular flat plate with a large aspect ratio, and is provided with the fixed-side gear 46 formed on one side surface along the extension direction of the gear plate 50. The fixed-side gear 46 has a plurality of teeth arranged at equal intervals in the extension direction of the gear plate 50. The gear plate 50 is fixed to an end portion on one side in the width direction that is a circumferential portion of the axial front side part of the upper column 11, with the extension direction of the gear plate 50 coinciding with the axial direction of the upper column 11 and with the fixed-side gear 46 facing outward in the width direction. With the front side part of the upper column 11 fitted within the rear side part of the lower column 10, the gear plate 50 is disposed within the recess 15 of the lower column 10, and part of the extension direction of the fixed-side gear 46 faces the one-side through-hole 16 of the lower column 10 in the width direction. In this example, the fixed side gear 46 is provided to the upper column 11 via a gear plate 50, which is another member, but when implementing the present invention, the fixed side gear can also be provided directly to the upper column, i.e., formed directly.

[0059] The locking engagement element 47 is supported on the lower column 10 so as to be movable toward and away from the fixed-side gear 46. The locking engagement element 47 also has a movable-side gear 51 that meshes with the fixed-side gear 46 when it approaches the fixed-side gear 46, and disengages from the fixed-side gear 46 when it moves away from the fixed-side gear 46.

[0060] When implementing the present invention, a structure can be adopted in which the locking engaging element includes a locking supported portion supported on a locking support portion provided on the lower column directly or via another member so as to be movable toward and away from the fixed gear, a movable gear, an unlocking elastic force receiving portion to which an unlocking preload spring applies elastic force in a direction away from the fixed gear, and a locking cam force receiving portion that is pressed by a locking cam surface in a direction toward the fixed gear directly or via another member. When implementing the present invention, any shape can be adopted for each of these components. In this example, the locking engaging element 47 is configured as a stepped pillar as a whole. That is, the locking engaging element 47 has a flange portion 52 protruding radially outward from a portion near its base end, a base end shaft portion 53 located adjacent to the base end side (outside in the width direction) of the flange portion 52, a tip end shaft portion 54 located adjacent to the tip end side (inside in the width direction) of the flange portion 52, and a movable gear 51 on the tip surface of the tip end shaft portion 54. The movable-side gear 51 has a plurality of teeth arranged at equal intervals in the extension direction of the fixed-side gear 46. The intermediate portion and base end portion of the tip shaft portion 54 have a cross-sectional shape that non-circularly fits into the one-side through-hole 16 of the lower column 10 so as to be non-rotatable relative to the one-side through-hole 16 and to allow axial movement of the one-side through-hole 16, in other words, a cross-sectional shape that is slightly smaller and similar to the cross-sectional shape of the one-side through-hole 16. In this example, the one-side through-hole 16 corresponds to the locking support portion, the intermediate portion and base end portion of the tip shaft portion 54 correspond to the locking supported portion, the flange portion 52 corresponds to the unlocking elastic force receiving portion, and the base-end shaft portion 53 corresponds to the locking cam force receiving portion.

[0061] The locking engagement element 47 is supported relative to the lower column 10 so as to be able to move towards and away from the fixed-side gear 46 in the width direction relative to the fixed-side gear 46, by non-circularly fitting the intermediate portion and base end portion of the tip shaft portion 54 into the one-side through-hole 16 of the lower column 10 so as to be non-rotatable but so as to be able to move in the axial direction of the one-side through-hole 16. In this example, it is possible to bring the locking engagement element 47 closer to the fixed-side gear 46 in the width direction, thereby engaging the movable-side gear 51 with the fixed-side gear 46, and to disengage the meshing between the movable-side gear 51 and the fixed-side gear 46 by moving the locking engagement element 47 away from the fixed-side gear 46 in the width direction.

[0062] The unlocking preload spring 48 applies an elastic force to the locking engagement element 47 in a direction away from the fixed-side gear 46. When implementing the present invention, a spring disposed between the locking engagement element and the lower column or a member fixed to the lower column can be used as the unlocking preload spring. In this example, the unlocking preload spring 48 is configured as an annular coiled wave spring, and is elastically sandwiched between the portion of the outer circumferential surface of the lower column 10 surrounding the one-side through-hole 16 and the side surface on the tip side of the flange portion 52 of the locking engagement element 47. As a result, the unlocking preload spring 48 applies an elastic force to the locking engagement element 47 in a direction away from the fixed-side gear 46 in the width direction. When implementing the present invention, the unlocking preload spring is not limited to a coiled wave spring, and various springs such as a coil spring or a leaf spring can be used as the unlocking preload spring.

[0063] The locking cam member 49 rotates together with the switching lever 3 around the central axis of the switching rod 27. For this reason, in this example, the locking cam member 49 is integrally connected to the base end of the switching lever 3.

[0064] The locking cam member 49 in this example is made integral with the switching lever 3 from a metal plate that constitutes the switching lever 3. The locking cam member 49 extends radially outward from a circumferential portion of the outer periphery of the base end of the switching lever 3, and has a generally fan-like shape whose circumferential width increases radially outward (see FIG. 9). At least a portion of the locking cam member 49 is positioned widthwise outward of the locking engaging element 47, regardless of the rotational position of the switching lever 3.

[0065] The locking cam member 49 of this example has a locking cam surface 55 on its inner surface in the width direction that pushes the locking engagement element 47 in a direction that brings it closer to the fixed-side gear 46, i.e., inward in the width direction. In this example, the locking cam surface 55 pushes the locking engagement element 47 inward in the width direction via a locking backup spring 56.

[0066] The locking cam surface 55 is an inclined surface whose position in the width direction, which is the direction in which the fixed gear 46 and the locking engaging element 47 approach each other, changes along the circumferential direction of the central axis of the switching rod 27. The portion of the locking cam surface 55 that presses the locking engaging element 47 when the switching lever 3 is in the locked position (part β1 in FIGS. 6 and 7 ) is located closer to the fixed gear 46 in the width direction (the lower side in FIGS. 6 and 10 , and the right side in FIGS. 7 and 11 ) than the portion that presses the locking engaging element 47 when the switching lever 3 is in the unlocked position (part β2 in FIGS. 10 and 11 ). When implementing the present invention, the overall shape of the locking cam member can be any shape as long as it has a locking cam surface (inclined surface). The locking cam member can also be formed as a separate member from the switching lever and fixed to the switching lever, switching rod, or the like.

[0067] In this example, the locking backup spring 56 is formed of a U-shaped leaf spring. The locking backup spring 56 has a fitting hole 57 at one end located on the inner side in the width direction, which is press-fitted onto the base-end shaft portion 53 of the locking engagement element 47, and a convex portion 58 at the other end located on the outer side in the width direction, which protrudes outward in the width direction, which is in contact with the locking cam surface 55. In this state, the locking backup spring 56 is elastically sandwiched between the side surface on the base end side of the flange portion 52 of the locking engagement element 47 and the locking cam surface 55. The spring constant of the locking backup spring 56 is greater than the spring constant of the unlocking preload spring 48. Therefore, in the assembled state of the steering device 1 of this example, the amount of compression of the unlocking preload spring 48 in the width direction is greater than the amount of compression of the locking backup spring 56 in the width direction. When carrying out the present invention, the backup locking spring is not limited to a leaf spring, and various springs such as a disc spring can be used.

[0068] In the structure of this example, when adjusting the longitudinal and height positions of the steering wheel, the switching lever 3 is rotated downward from the rotation position in the locked state shown in FIG. 5 to the rotation position in the unlocked state shown in FIG. 9.

[0069] This reduces the axial dimension of the cam device 29, thereby increasing the gap between the driven cam 34 and the thrust bearing 30. As a result, the frictional force acting between the widthwise inner surfaces of the two support plate portions 25a, 25b and the widthwise outer surfaces of the two flange portions 13 is reduced or lost, and the inner diameter of the lower column 10 expands to a free state, so that the frictional force acting between the inner peripheral surface of the lower column 10 and the outer peripheral surface of the upper column 11 is reduced or lost.

[0070] Furthermore, when the switching lever 3 rotates from the rotation position for the locked state to the rotation position for the unlocked state as described above, the portion of the locking cam surface 55 that presses the locking engagement element 47 changes from the β1 portion shown in FIGS. 6 and 7 to the β2 portion shown in FIGS. 10 and 11. That is, the widthwise position of the portion of the locking cam surface 55 that presses the locking engagement element 47 changes in a direction away from the fixed-side gear 46. As a result, as shown in FIG. 11, the locking engagement element 47 is pushed outward in the widthwise direction by the elastic force of the unlocking preload spring 48, and moves to a position where the meshing between the fixed-side gear 46 and the movable-side gear 51 is released.

[0071] Furthermore, when the switching lever 3 rotates from the rotation position in the locked state to the rotation position in the unlocked state as described above, the portion of the restricting cam surface 42 that presses the restricting engagement member 4 changes from the α1 portion shown in Figures 6 and 7 to the α2 portion shown in Figures 10 and 11. That is, the widthwise position of the portion of the restricting cam surface 42 that presses the restricting engagement member 4 changes in a direction approaching the restricting elongated hole 20. As a result, as shown in Figure 11, the restricting engagement member 4 is pressed inward in the widthwise direction by the restricting cam surface 42, and the tip shaft portion 38 of the restricting engagement member 4 moves to a position where it enters the restricting elongated hole 20.

[0072] In this state, by swinging the steering column 2 around the tilt shaft 19, the height position of the steering wheel can be adjusted within the range in which the switching rod 27 can move inside the tilt elongated hole 26. Furthermore, by displacing the upper column 11 in the axial direction relative to the lower column 10, the front-to-rear position of the steering wheel can be adjusted within the range in which the tip shaft portion 38 of the regulating engagement element 4 can move inside the regulating elongated hole 20.

[0073] After adjusting the longitudinal and height positions of the steering wheel, the switching lever 3 is rotated upward from the rotation position in the unlocked state shown in FIG. 9 to the rotation position in the locked state shown in FIG.

[0074] This increases the axial dimension of the cam device 29, thereby reducing the gap between the driven cam 34 and the thrust bearing 30. As a result, the frictional force acting between the widthwise inner surfaces of the two support plate portions 25a, 25b and the widthwise outer surfaces of the two flange portions 13 increases, and the inner diameter of the lower column 10 elastically contracts, thereby increasing the frictional force acting between the inner peripheral surface of the lower column 10 and the outer peripheral surface of the upper column 11.

[0075] Furthermore, when the switching lever 3 rotates from the rotation position for the unlocked state to the rotation position for the locked state as described above, the portion of the locking cam surface 55 that presses the locking engagement member 47 changes from the β2 portion in FIGS. 10 and 11 to the β1 portion shown in FIGS. 6 and 7. That is, the widthwise position of the portion of the locking cam surface 55 that presses the locking engagement member 47 changes in a direction approaching the fixed-side gear 46. As a result, as shown in FIG. 7, the locking engagement member 47 is pressed inward in the widthwise direction by the locking cam surface 55 and moves to a position where the fixed-side gear 46 and the movable-side gear 51 mesh with each other.

[0076] Furthermore, when the switching lever 3 rotates from the rotation position for the unlocked state to the rotation position for the locked state as described above, the portion of the restricting cam surface 42 that presses the restricting engagement element 4 changes from the α2 portion shown in FIGS. 10 and 11 to the α1 portion shown in FIGS. 6 and 7. That is, the widthwise position of the portion of the restricting cam surface 42 that presses the restricting engagement element 4 changes in a direction away from the restricting elongated hole 20. As a result, as shown in FIG. 7, the restricting engagement element 4 is pushed outward in the widthwise direction by the elastic force of the restricting release preload spring 5, and the tip shaft portion 38 of the restricting engagement element 4 moves to a position where it comes out of the restricting elongated hole 20.

[0077] In this state, the steering column 2 cannot be swung about the tilt shaft 19 based on the frictional force acting between the widthwise inner surfaces of the two support plate portions 25a, 25b and the widthwise outer surfaces of the two flange portions 13, i.e., it is not possible to adjust the height position of the steering wheel. Also, the frictional force acting between the inner circumferential surface of the lower column 10 and the outer circumferential surface of the upper column 11, and the meshing force between the fixed-side gear 46 and the movable-side gear 51, make it not possible to displace the upper column 11 in the axial direction relative to the lower column 10, i.e., it is not possible to adjust the fore-aft position of the steering wheel. As a result, the steering wheel is held in the adjusted fore-aft position and height position.

[0078] In the structure of this example, the spring constant of the restricting backup spring 43 is set to be larger than the spring constant of the derestriction preload spring 5, and the spring constant of the locking backup spring 56 is set to be larger than the spring constant of the unlocking preload spring 48. Therefore, when switching between the locked state and the unlocked state, the change in the compression amount of the restricting backup spring 43 and the locking backup spring 56 is kept small, but the compression amount of the derestriction preload spring 5 and the unlocking preload spring 48 changes greatly. In other words, the change in the compression amount of the springs at this time is mostly the change in the compression amount of the derestriction preload spring 5 and the unlocking preload spring 48.

[0079] In the structure of this example, the role of the reserve regulating spring 43 is to increase the compression amount of the reserve regulating spring 43 so that the rotation of the switching lever 3 can continue even after the compression amount of the release preload spring 5 reaches its maximum during the rotation of the switching lever 3 when switching from the locked state to the unlocked state. Therefore, if a setting is adopted in which the compression amount of the release preload spring 5 does not reach its maximum during the rotation of the switching lever 3, the installation of the reserve regulating spring 43 can be omitted. Alternatively, even if a setting is adopted in which the compression amount of the release preload spring 5 reaches its maximum during the rotation of the switching lever 3, the installation of the reserve regulating spring 43 can be omitted if the rotation of the switching lever 3 can continue by bending the regulating cam member 6 after the compression amount reaches its maximum.

[0080] In the structure of this example, the role of the locking backup spring 56 is to increase the compression amount of the locking backup spring 56 so that, when switching from the unlocked state to the locked state, even after the tooth crest surfaces of the fixed-side gear 46 and the movable-side gear 51 come into contact with each other and the locking engagement element 47 no longer moves inward in the width direction during the rotation of the switching lever 3, the rotation of the switching lever 3 can continue. Therefore, if the rotation of the switching lever 3 can be continued by bending the locking cam member 49 after the locking engagement element 47 no longer moves inward in the width direction during the rotation of the switching lever 3, the installation of the locking backup spring 56 can be omitted.

[0081] If the vehicle crashes while the steering wheel is held in the adjusted longitudinal and height positions, and a secondary collision occurs in which the driver's body hits the steering wheel, a forward impact load is applied from the steering wheel to the upper column 11 via the upper shaft 22. This impact load then releases the meshing between the fixed-side gear 46 and the movable-side gear 51, and the upper column 11 is displaced forward relative to the lower column 10.

[0082] At this time, the impact load during the secondary collision is absorbed based on the axial sliding between the outer peripheral surface of the upper column 11 and the inner peripheral surface of the lower column 10. When implementing the present invention, it is also possible to install an impact absorbing member that plastically deforms at this time, and to further absorb the impact load during the secondary collision based on this plastic deformation.

[0083] In particular, in this example, when the upper column 11 is displaced forward relative to the lower column 10 as described above, the tip shaft portion 38 of the restricting engagement element 4 comes out of the restricting elongated hole 20. Therefore, compared to when adjusting the position of the steering wheel, the amount by which the upper column 11 can be displaced forward relative to the lower column 10 can be increased, thereby enabling enhanced protection of the driver.

[0084] Furthermore, in this example, the restricting engagement element 4 is not fixed to the impact absorbing member. Therefore, even if the front or rear end of the restricting elongated hole 20 hits the tip shaft 38 of the restricting engagement element 4 with force when adjusting the fore-aft position of the steering wheel in the unlocked state, the impact absorbing member will not be deformed, and the impact absorbing performance will not become unstable.

[0085] Although one embodiment of the present invention has been described above, the present invention is not limited to this and can be modified as appropriate within the scope of the technical concept of the invention.

[0086] When implementing the present invention, the locations in the width direction of the telescopic range limiting element including the restricting elongated hole, the restricting engaging element, the release preload spring, and the restricting cam member, and the locking element including the fixed gear, the locking engaging element, the release preload spring, and the locking cam member, can be reversed from those in the above-described embodiment. That is, the telescopic range limiting element can be located on the same side as the switching lever in the width direction, and the locking element can be located on the opposite side of the switching lever in the width direction. In this case, for example, the restricting cam member can be integrally connected to the base end of the switching lever, or the locking cam member can be non-rotatably fitted to the switching rod that rotates together with the switching lever.

[0087] When implementing the present invention, if a locking element including a locking engaging element having a fixed side gear and a movable side gear is installed, the engagement and disengagement of the fixed side gear and the movable side gear in response to the rotation of the switching lever can also be achieved using an appropriate mechanism other than the unlocking preload spring and the locking cam member.

[0088] When implementing the present invention, if a mechanism other than a locking element including a fixed side gear and a locking engaging element having a movable side gear (for example, a mechanism that increases or decreases the frictional force acting between the inner surface of the outer column and the outer surface of the inner column, as in the above-described embodiment) is used as a switching mechanism for switching between a locked state that makes it impossible to adjust the fore-aft position of the steering wheel and an unlocked state that makes such adjustment possible, then the locking element can be omitted.

[0089] When implementing the present invention, if a mechanism other than a mechanism for increasing or decreasing the frictional force acting between the inner circumferential surface of the outer column and the outer circumferential surface of the inner column (for example, the locking element) is provided as a switching mechanism for switching between a locked state that disables adjustment of the fore-aft position of the steering wheel and an unlocked state that enables such adjustment, the mechanism for increasing or decreasing the frictional force can be omitted. In this case, a switching rod having a width dimension equal to or greater than that of the steering column can be omitted, and a shorter shaft can be used as the shaft that serves as the rotation center of the switching lever.

[0090] When the present invention is put into practice, the elongated regulating hole and / or the fixed-side gear can also be installed in a portion circumferentially offset from the widthwise end of the upper column. [Explanation of symbols]

[0091] 1 Steering device 2 steering column 3 Switching lever 4 Regulatory engager 5. Preload spring for deregulation 6. Regulating cam member 7 Switching mechanism 8 Steering shaft 9 Support Bracket 10 Roar Column 11 Upper Column 12 Slit 13 Flange 14 Through hole 15 recess 16 One-side through hole 17 Other side through hole 18 Insertion hole 19 Tilt axis 20 Regulatory slot 21 Lower shaft 22 Upper shaft 23 Rolling bearings 24 Mounting plate 25a, 25b Support plate part 26 Tilt slot 27 Switching rod 28 Nut 29 Cam device 30 Thrust bearing 31 Head 32 Male thread 33 Drive cam 34 Driven cam 35 Tsuba 36 Proximal shaft part 37 Intermediate shaft 38 Tip shaft 39 Circuit Board 40 Connection plate 41 Cam plate part 42 Regulating cam surface 43 Spare spring for regulation 44 Fitting hole 45 Convex part 46 Fixed gear 47 Locking engagement element 48 Preload spring for unlocking 49 Locking cam member 50 gear plate 51 Movable gear 52 Tsuba 53 Proximal shaft part 54 Tip shaft 55 Locking cam surface 56 Spare lock spring 57 Fitting hole 58 Convex part 100 Steering device 101 Steering Wheel 102 steering shaft 103 Steering column 104a, 104b Universal joint 105 Intermediate shaft 106 Steering gear unit 107 Pinion shaft 108 tie rod

Claims

1. a steering column including a lower column, an upper column combined with the lower column to be able to displace in an axial direction, and a restriction elongated hole that is provided in the upper column directly or via another member and extends in the axial direction of the upper column; a switching lever that is supported by the lower column so as to be rotatable about a rotation central axis in the width direction, and that is switchable between a locked state that disables adjustment of the fore-and-aft position of the steering wheel and an unlocked state that enables such adjustment, based on changing the rotation position about the rotation central axis; a restriction engaging element that is supported by the lower column so as to be movable toward and away from the restriction elongated hole, and that is capable of entering the restriction elongated hole when it approaches the restriction elongated hole and of coming out of the restriction elongated hole when it moves away from the restriction elongated hole; a restriction release preload spring that applies a resilient force to the restriction engaging element in a direction away from the restriction elongated hole; a regulating cam member that rotates together with the switching lever about the rotation central axis, The restricting cam member has a restricting cam surface that pushes the restricting engagement piece in a direction toward the restricting elongated hole, the restricting cam surface is an inclined surface whose position in the direction away from the restricting elongated hole and the restricting engaging element changes along the circumferential direction of the pivot central axis, and a portion that presses the restricting engaging element when the switching lever is in the rotation position for the unlocked state is located closer to the restricting elongated hole than a portion that presses the restricting engaging element when the switching lever is in the rotation position for the locked state, As the switching lever rotates from the rotation position in the locked state to the rotation position in the unlocked state, the restricting engagement piece is pushed by the restricting cam surface to move to a position where it enters the restricting elongated hole, and as the switching lever rotates from the rotation position in the unlocked state to the rotation position in the locked state, the restricting engagement piece is pushed by the elastic force of the restricting release preload spring to move to a position where it comes out of the restricting elongated hole. Steering device.

2. a fixed gear that is provided on the upper column directly or via another member and extends in the axial direction; a locking engager having a movable gear supported by the lower column so as to be movable toward and away from the fixed-side gear, which engages with the fixed-side gear when it approaches the fixed-side gear and is released from engagement with the fixed-side gear when it moves away from the fixed-side gear, As the switching lever rotates from the rotation position in the locked state to the rotation position in the unlocked state, the locking engagement piece moves away to a position where the fixed side gear and the movable side gear are disengaged from each other, and as the switching lever rotates from the rotation position in the unlocked state to the rotation position in the locked state, the locking engagement piece moves closer to a position where the fixed side gear and the movable side gear are engaged with each other. The steering device according to claim 1 .

3. an unlocking preload spring that applies elastic force to the locking engagement element in a direction away from the fixed-side gear; a locking cam member that rotates together with the switching lever about the rotation central axis, the locking cam member has a locking cam surface that pushes the locking engagement element in a direction toward the fixed-side gear, the locking cam surface is an inclined surface whose position changes in relation to the direction in which the fixed-side gear and the locking engaging element are spaced apart along the circumferential direction of the rotation central axis, and a portion that presses the locking engaging element when the switching lever is in a rotation position for the locked state is located closer to the fixed-side gear than a portion that presses the locking engaging element when the switching lever is in a rotation position for the unlocked state, As the switching lever rotates from the rotation position in the locked state to the rotation position in the unlocked state, the locking engagement piece is pushed by the elastic force of the unlocking preload spring and moves to a position where the meshing between the fixed side gear and the movable side gear is released, and as the switching lever rotates from the rotation position in the unlocked state to the rotation position in the locked state, the locking engagement piece is pushed by the locking cam surface and moves to a position where the fixed side gear and the movable side gear mesh. The steering device according to claim 2 .

Images