Patent Application
20190111962
The present invention relates to improvements on a position adjustment device for steering wheel. The position adjustment device for steering wheel has a function of adjusting a position in a front and rear direction or a vertical position of a steering wheel for steering an automobile, for example.
A steering device for automobile is configured as shown in
Regarding the steering device configured as described above, a steering device including a tilt mechanism for adjusting a vertical position of the steering wheel 1 and a telescopic mechanism for adjusting a position in a front and rear position in correspondence to a physique and a driving posture of a driver has been known (for example, refer to Patent Document 1).
In the shown structure, in order to configure the tilt mechanism, an upper front end portion of a housing 10 fixed to a front end portion of the steering column 6 is supported to a vehicle body 11 so that it can oscillate and be displaced by a tilt shaft 12 arranged in a width direction (the width direction indicates a width direction of the vehicle body and coincides with the left and right direction. This applies to the specification and the claims, too.). Also, a displacement bracket 13 is provided on a lower surface of an axially intermediate part of the steering column 6. A support bracket 14 is provided with clamping the displacement bracket 13 from both sides in the width direction. A pair of left and right support plate parts 22, 22 configuring the support bracket 14 is respectively formed with long holes 15 for tilt adjustment, which are long in a vertical direction. The displacement bracket 13 is formed at portions, which align with portions of both the long holes 15 for tilt adjustment, with long holes 16 for telescopic adjustment. An adjustment rod 17 is inserted in the long holes 15 for tilt adjustment and the long holes 16 for telescopic adjustment in the width direction. Also, in order to configure a telescopic mechanism, the steering shaft 5 and the steering column 6 are configured to be expanded and contracted, and the long holes 16 for telescopic adjustment are configured as long holes, which are long in a front and rear direction. When an adjustment lever (not shown) provided at one end portion of the adjustment rod 17 is operated, a force of clamping the displacement bracket 13 from both sides in the width direction by the support bracket 14 is adjusted, so that a state (unlocked state) in which a position of the steering wheel 1 can be adjusted and a state (locked state) in which the steering wheel can be kept at a position after adjustment are switched each other.
A more specific structure of the steering device is described with reference to
A front part of an outer column 18 arranged at a rear side of the steering column 6 and a rear part of an inner column 19 arranged at a front side are slidably fitted, so that an entire length of the steering column 6 can be extended or shortened. For example, the front part of the outer column 18 manufactured by die-casting a light alloy is provided with a slit 20, so that an inner diameter of the front part can be elastically expanded and contracted. Also, a pair of left and right clamped plate parts 21, 21 is provided at parts at which the slit 20 is clamped from both the left and right sides, and the displacement bracket 13 is configured by both the clamped plate parts 21, 21. Also, the pair of clamped parts 21, 21 is formed with long holes 16, 16 for telescopic adjustment, which are long in the front and rear direction. Also, a pair of left and right support plate parts 22, 22 provided to the support bracket 14 is arranged at parts at which the displacement bracket 13 is clamped from both the left and right sides. The pair of support plate parts 22, 22 is formed with long holes 15, 15 for tilt adjustment, each of which has a partial arc shape about a tilt shaft 12 (refer to
One axial end portion (a left end portion in
When adjusting a position of the steering wheel 1, the adjustment lever 23 is caused to oscillate in a predetermined direction (in general, downward) to rotate the drive-side cam 37c in an unlocking direction, which is a rotation direction upon switching to the unlocked state. Then, an axial dimension of the cam device 57 is reduced and an interval between the driven-side cam 38c and the nut 24 is expanded. As a result, surface pressures of contact parts between the inner surfaces of the pair of support plate parts 22, 22 and outer surfaces of the pair of clamped parts 21, 21 are reduced or lost, the inner diameter of the front end portion of the outer column 18 is elastically enlarged, and a surface pressure of a contact part between an inner peripheral surface of the front end portion of the outer column 18 and an outer peripheral surface of the rear end portion of the inner column 19 is reduced. In this state, a position of the steering wheel 1 can be adjusted in the vertical direction and in the front and rear direction within a range in which the adjustment rod 17 can move in both the long holes 15, 15 for tilt adjustment and both the long holes 16, 16 for telescopic adjustment.
In order to keep the steering wheel 1 at a desired position, the steering wheel 1 is moved to the desired position and the adjustment lever 23 is then caused to oscillate in a reverse direction (generally, upward). Thereby, the drive-side cam 37c is rotated in a locking direction, which is a rotation direction upon switching to the lock state. Then, the axial dimension of the cam device 57 is enlarged, and the interval between the inner surfaces of the pair of support plate parts 22, 22 is reduced. In this state, the surface pressures of the contact parts between the inner surfaces of the pair of support plate parts 22, 22 and the outer surfaces of the pair of clamped parts 21, 21 are increased, the inner diameter of the front end portion of the outer column 18 is elastically reduced, and the surface pressure of the contact part between the inner peripheral surface of the front end portion of the outer column 18 and the outer peripheral surface of the rear end portion of the inner column 19 is increased. As a result, it is possible to keep the steering wheel 1 at a position after the adjustment.
According to the steering device configured as described above, the vertical position and the position in the front and rear direction of the steering wheel 1 are kept at the positions after the adjustment by a frictional force that is applied between the pair of support plate parts 22, 22 and the pair of clamped parts 21, 21, and the like. However, for example, from a standpoint of securely protecting a driver upon a secondary collision and the like, there are needs for a structure capable of more firmly keeping the position of the steering wheel 1.
The present invention has been made in view of the above situations, and is to implement a structure capable of firmly keeping a position of a steering wheel in a state where a vertical position or a position in a front and rear direction of the steering wheel can be kept at a position after adjustment.
A position adjustment device for steering wheel of the present invention includes a displacement bracket, a fixed-side bracket, an adjustment rod, a pair of pressing parts, and an expansion/contraction device.
The displacement bracket is fixed to a steering column and is formed with a first through-hole.
The fixed-side bracket has a pair of support plate parts provided with clamping the displacement bracket from both sides in a width direction, is formed with a pair of second through-holes, and is fixed to a vehicle body side.
The adjustment rod is provided with being inserted in the first through-hole and the pair of second through-holes in the width direction.
The pair of pressing parts is provided at both end portions of the adjustment rod, which protrude from outer surfaces of the pair of support plate parts.
The expansion/contraction device is configured to expand and contract an interval between the pair of pressing parts.
Also, at least one through-hole of the first through-hole and the pair of second through-holes is configured as a long hole for adjustment that is long in a position adjustment direction, which is a direction in which a position of the steering wheel can be adjusted. In the meantime, the position adjustment direction is a front and rear direction when a position of the steering wheel is to be adjusted by a telescopic mechanism, and is a vertical direction when the position of the steering wheel is to be adjusted by a tilt mechanism.
An unlocked state in which the steering wheel can be positionally adjusted in the position adjustment direction and a locked state in which the steering wheel can be kept at a position after adjustment can be switched each other on the basis of expansion/contraction of the expansion/contraction mechanism.
In particular, the position adjustment device for steering wheel of the present invention includes a lock mechanism configured to prevent the displacement bracket from being displaced relative to the fixed-side bracket in the position adjustment direction, in the locked state.
The lock mechanism includes a fixed-side engagement part and a moveable-side lock member.
The fixed-side engagement part is provided directly or via another member to a bracket, which has the long hole for adjustment formed therein, of the fixed-side bracket or the displacement bracket.
The moveable-side lock member has a moveable-side engagement part capable of friction engagement or concave-convex engagement with the fixed-side engagement part, and is supported to the adjustment rod in a state where the moveable-side lock member can be synchronously displaced in the position adjustment direction and in a rotation direction about a central axis of the adjustment rod.
When switching from the unlocked state to the locked state, the moveable-side lock member rotates in a locking direction, so that the fixed-side engagement part and the moveable-side engagement part are friction-engaged or concave-convex-engaged so as to prevent displacement of the adjustment rod in the position adjustment direction.
On the other hand, when switching from the locked state to the unlocked state, the moveable-side lock member rotates in an unlocking direction, so that the friction engagement or the concave-convex engagement between the fixed-side engagement part and the moveable-side engagement part is released.
When implementing the position adjustment device for steering wheel of the present invention, in the locked state, a rotating force in the locking direction may be applied to the moveable-side lock member, based on a force to be applied to the adjustment rod in the position adjustment direction (for example, an impact force that is to be applied in association with leaning against a steering wheel upon a secondary collision or when a driver gets in or off a vehicle).
When implementing the position adjustment device for steering wheel of the present invention, a part, which is to align in the position adjustment direction with an engagement part between the fixed-side engagement part and the moveable-side engagement part in the locked state, of the moveable-side lock member may be configured to have a thickness (wedge shape), which increases in a direction perpendicular to the position adjustment direction as a distance from the central axis of the adjustment rod in the position adjustment direction increases, and to generate a wedge effect between the fixed-side engagement part and the adjustment rod on the basis of a force to be applied to the adjustment rod in the position adjustment direction.
When implementing the position adjustment device for steering wheel of the present invention, the moveable-side lock member may be arranged with being retained in the width direction between an outer surface in the width direction of at least one support plate of the pair of support plate parts configuring the fixed-side bracket and a pressing part, which is provided at an outer side of the one support plate part in the width direction, of the pair of pressing parts or between an inner surface of the one support plate part in the width direction and an outer surface of the displacement bracket in the width direction facing the inner surface of the one support plate part in the width direction.
When implementing the position adjustment device for steering wheel of the present invention, the fixed-side engagement part may be configured by a fixed-side friction surface (a flat surface, a flat surface subjected to a surface treatment, or the like) formed to be parallel in the position adjustment direction.
The moveable-side engagement part may be configured so that a distance from the central axis of the adjustment rod increases from a position, at which the moveable-side engagement part is to be friction-engaged with the fixed-side engagement part in the locked state, toward an opposite direction to the locking direction.
When implementing the position adjustment device for steering wheel of the present invention, the fixed-side engagement part may be configured by a first fixed-side engagement part and a second fixed-side engagement part, and the moveable-side engagement part may be configured by a first moveable-side engagement part and a second moveable-side engagement part. In the locked state, the first moveable-side engagement part and the first fixed-side engagement part may be engaged, and the second moveable-side engagement part and the second fixed-side engagement part may be engaged.
When implementing the position adjustment device for steering wheel of the present invention, the moveable-side lock member may have an elastic arm part, and the moveable-side lock member may be supported to the adjustment rod via the elastic arm part (may be supported to the adjustment rod so as to be relatively rotatable within an elasticity range of a pair of elastic arm parts).
According to the position adjustment device for steering wheel of the present invention, it is possible to firmly keep a position of the steering wheel in the state (locked state) where the vertical position or the position in the front and rear direction of the steering wheel can be kept at a position after adjustment.
That is, according to the present invention, in the locked state, the fixed-side engagement part provided directly (or indirectly) to the bracket, which has the long hole for adjustment formed therein, of the fixed-side bracket and the displacement bracket and the moveable-side engagement part of the moveable-side lock member supported to the adjustment rod so as to be synchronously displaceable in the position adjustment direction are engaged with each other (friction engagement or concave-convex engagement) so as to prevent displacement of the adjustment rod in the position adjustment direction. For this reason, in the locked state, even when an impact load is applied to the steering wheel in the position adjustment direction, it is possible to prevent the steering wheel from being displaced in the position adjustment direction on the basis of the engagement.
A first example of an embodiment of the present invention will be described with reference to
That is, a steering device to which a position adjustment device for steering wheel of the first example can be applied is configured to transmit rotation of a steering wheel 1 (refer to
The steering wheel 1 is supported and fixed to a rear end portion of a steering shaft 5. The steering shaft 5 is rotatably supported to a cylindrical steering column 6a with being inserted in the steering column 6a in an axial direction. Also, as shown in
The steering shaft 5 having the rear end portion to which the steering wheel 1 is supported and fixed is configured to adjust a position of an outer shaft 28 in a front and rear direction by spline-engaging a front end portion of the outer shaft 28 provided at a rear side (a right side in
A front part of an outer column 18a arranged at a rear side of the steering column 6a and a rear part of an inner column 19a arranged at a front side are slidably fitted, so that an entire length of the steering column 6a can be extended or shortened. For example, an upper end portion of the front part of the outer column 18a manufactured by die-casting a light alloy is provided with a slit 20a, so that an inner diameter of the front part can be elastically expanded and contracted. Also, a pair of left and right clamped plate parts 21a, 21a is provided at parts at which the slit 20a is clamped from both the left and right sides, and a displacement bracket 13a is configured by the pair of clamped parts 21a, 21a. Also, the pair of clamped parts 21, 21a is formed with long holes 16a, 16a for telescopic adjustment, which are long in the front and rear direction.
Also, a housing 10 (refer to
Also, a support bracket 14a is provided with clamping the displacement bracket 13a from both sides in the width direction. The support bracket 14a has an attachment plate part 30 provided at an upper part and a pair of left and right support plate parts 22a, 22b hanging down from the attachment plate part 30. In the first example, upper end edges of the pair of support plate parts 22a, 22b are made to be continuous by a coupling plate part 31, and an upper surface of the coupling plate part 31 is fixed to a lower surface of a central portion of the attachment plate part 30 in the width direction by welding. The support bracket 14a is supported to the vehicle body via a pair of separation capsules 32, 32 (refer to
Also, the pair of support plate parts 22a, 22b is formed with a pair of long holes 15a, 15b for tilt adjustment, each of which has a partial arc shape about the tilt shaft 12 and is long in the vertical direction. In the meantime, the pair of long holes 15a, 15b for tilt adjustment may also be formed to have a rectangular shape, which is long in the vertical direction, other than the partial arc shape. In the first example, the pair of long holes 16a, 16b for telescopic adjustment corresponds to the first through-hole defined in the claims, and the pair of long holes 15a, 15b for tilt adjustment corresponds to the second through-holes defined in the claims. Also, the pair of long holes 15a, 15b for tilt adjustment corresponds to the long hole for adjustment defined in the claims, and the formation direction (vertical direction) of the pair of long holes 15a, 15b for tilt adjustment corresponds to the position adjustment direction defined in the claims.
By the above configuration, it is possible to adjust the vertical position of the steering wheel 1, based on oscillation and displacement about the tilt shaft 12, and to adjust the position in the front and rear direction of the steering wheel 1, based on the expansion and contraction of the steering shaft 5 and the steering column 6a.
An adjustment rod 17a is inserted in the pair of long holes 15a, 15b for tilt adjustment and the pair of long holes 16a, 16b for telescopic adjustment in the width direction. The adjustment rod 17a has a male screw part (not shown) formed at one axial end portion (a right end portion in
The non-circular part 33 is provided from a part of the adjustment rod 17a, which is arranged at an inner side of the other (left, in
Specifically, the non-circular part 33 has a pair of flat surface parts 35a, 35b formed by cutting two positions on an outer peripheral surface opposite to each other in a radial direction into a flat surface shape, and a pair of pressing curved surface parts 36a, 36b formed between the pair of flat surface parts 35a, 35b in a circumferential direction of the adjustment rod 17a and having an arc-shaped section about a central axis of the non-circular part 33. A sectional shape of the non-circular part 33 has twofold symmetry (a shape that overlaps itself when rotated by 180°). A distance between the pair of flat surface parts 35a, 35b is smaller than a distance between apexes of the pair of pressing curved surface parts 36a, 36b.
In the first example, in a state (unlocked state) shown in
Also, in the first example, a pressing plate 25 and a thrust bearing 26a are arranged in corresponding order from one support plate part 22a between a nut 24a screwed to the male screw part of the adjustment rod 17a and the one (right, in
Also, a driven-side cam 37, a drive-side cam 38, an adjustment lever 23 and a lock mechanism 39 are arranged between the head part 34 of the adjustment rod 17a and the other (left, in
The driven-side cam 37 configures a cam device corresponding to the expansion/contraction mechanism defined in the claims, together with the drive-side cam 38. Also, the driven-side cam 37 is made of sintered metal, for example, is formed with a central hole 58 for inserting therein the adjustment rod 17a, and has a circular ring plate shape as a whole. Also, the driven-side cam 37 has a driven-side cam surface, which is a circumferential concave-convex surface, on an outer surface (left surface, in
The driven-side cam 37 is externally fitted so as to be rotatable relative to the adjustment rod 17a and to be relatively displaceable in the width direction (the axial direction of the adjustment rod 17a) in a state where a part close to the other axial end of the adjustment rod 17a is inserted in the central hole 58.
One (front) guide convex part 60a of the pair of guide convex parts 60a, 60b is arranged at a front side of a front side frame part 62 configuring the rectangular frame-shaped convex part 61. The other (rear) guide convex part 60b of the pair of guide convex parts 60a, 60b is arranged at a rear side of a rear side frame part 63 configuring the rectangular frame-shaped convex part 61. In this state, a rear surface of the one guide convex part 60a and a front surface of the front side frame part 62 are made to closely face each other, and a front surface of the other guide convex part 60b and a rear surface of the rear side frame part 63 are made to closely face each other. By doing so, rotation of the driven-side cam 37 relative to the other support plate part 22b is locked. In the meantime, in a structure where the rectangular frame-shaped convex part 61 is not provided, the other support plate part 22b is provided with an engagement part that can lock the rotation of the driven-side cam 37 relative to the other support plate part 22b by engagement with the pair of guide convex parts 60a, 60b.
In the meantime, the drive-side cam 38 is made of sintered metal, for example, is formed with a central hole 59 for inserting therein the adjustment rod 17a, and has a circular ring plate shape or a rectangular plate shape as a whole. In the first example, an inner peripheral surface of the central hole 59 of the drive-side cam 38 is formed to have a shape capable of non-circular fitting with the outer peripheral surface of the non-circular part 33 of the adjustment rod 17a. Also, an inner surface (right surface, in
The drive-side cam 38 is mounted in a state where an outer peripheral surface (a portion of the non-circular part 33) of a part, which is located further toward the other axial end side than the part to which the driven-side cam 37 is externally fitted, of the part close to the other axial end of the adjustment rod 17a is fitted to the central hole 59 in a non-circular form. Also, in this state, the drive-side engaging convex part 40 is engaged to a lever-side through-hole 4 formed at a base end portion of the adjustment lever 23. In this way, the drive-side cam 38 is configured to rotate integrally with the adjustment lever 23.
In the meantime, the part close to the other axial end of the adjustment rod 17a is press-fitted in the central hole 59 of the drive-side cam 38, so that the drive-side cam 38 and the adjustment rod 17a can be integrally rotated.
By the above configuration, the adjustment lever 23, the drive-side cam 38 and the adjustment rod 17a are mounted to be integrally rotatable.
Also, the lock mechanism 39 includes a fixed-side tooth part 42, a moveable-side lock member 43, and the non-circular part 33 provided to the adjustment rod 17a. The lock mechanism 39 is to prevent the vertical displacement of the adjustment rod 17a by concave-convex engagement, in the locked state.
The fixed-side tooth part 42 corresponds to the fixed-side engagement part defined in the claims. The fixed-side tooth part 42 is configured by a concave-convex part formed on the outer surface in the width direction of the other support plate part 22b in a direction parallel with the formation direction (vertical direction) of the other long hole 15b for tilt adjustment (the description ‘parallel with the formation direction of the long hole for tilt adjustment’ includes a substantially parallel state as well inasmuch as the fixed-side tooth part 42 and a moveable-side tooth part 49 of the moveable-side lock member 43 are concave-convex-engaged in the locked state, so that the vertical holding force of the steering wheel 1 can be made as high as possible.). The same applies hereinafter). In the meantime, the fixed-side tooth part 42 may be directly formed on the other support plate part 22b or may be formed on other member (for example, a plate-shaped member and the like) fixed (for example, welded) to the other support plate part 22b.
Specifically, in the first example, a part, which is adjacent to the other long hole 15b for tilt adjustment in the front and rear direction and the vertical direction, of the outer surface of the other support plate part 22b in the width direction is formed with a concave part 44. In the first example, the concave part 44 has a substantially rectangular shape, which is long in the vertical direction, as seen in the width direction. However, the present invention is not limited to the shape. A front surface and a rear surface of the concave part 44 are parallel with the formation direction of the other long hole 15b for tilt adjustment. The front surface of the concave part 44 is formed with the fixed-side tooth part 42.
In the meantime, in the first example, a part, which surrounds the other long hole 15b for tilt adjustment, of the outer surface of the other support plate part 22b in the width direction is subjected to press working on the inner surface of the other support plate part 22b in the width direction, so that the rectangular frame-shaped convex part 61, as seen in the width direction, is formed. A part surrounded by the rectangular frame-shaped convex part is configured as the concave part 44. In the meantime, the concave part 44 may also be formed by further recessing the part, which surrounds the other long hole 15b for tilt adjustment, of the outer surface of the other support plate part 22b in the width direction than the other part.
In the meantime, the fixed-side tooth part 42 may be formed on the rear surface of the concave part 44, other than the front surface thereof. Also, although not shown, as another aspect of forming the fixed-side tooth part 42, parts, which are located more forward and rearward than the other long hole 15b for tilt adjustment, of the outer surface of the other support plate part 22b in the width direction may be formed with a pair of vertical convex parts parallel with the formation direction of the other long hole 15b for tilt adjustment and protruding outward in the width direction, and a rear surface of one (front) vertical convex part of the pair of vertical convex parts (or a front surface of the other vertical convex part) may be formed with the fixed-side tooth part 42. Alternatively, both end portions in the front and rear direction of a plate-shaped member separately provided from the other support plate part 22b may be formed with a pair of vertical convex parts, and a rear surface of one vertical convex part of the pair of vertical convex parts (or a front surface of the other vertical convex part) may be formed with the fixed-side tooth part 42. When this configuration is adopted, the plate-shaped member is fixed to the other support plate part 22b by welding.
The moveable-side lock member 43 is made by punch pressing a metal plate having elasticity, and has a main body part 45, a wedge part 46, a pair of support parts 47a, 47b, and a pair of arm parts 48a, 48b corresponding to the pair of elastic arm parts defined in the claims. A structure of the moveable-side lock member 43 is described with reference to a mounted state shown in
The main body part 45 is substantially cylindrical. Specifically, an outer edge (outer periphery) of the main body part 45 is configured by a part shown with a solid line α1 in
The wedge part 46 has a substantially triangular shape, as seen in the width direction, and continues to a circumferential part (which is an upper end portion in the unlocked state and is shown with the dashed-two dotted line Pi in
The pair of support parts 47a, 47b is provided to protrude radially inward at two positions in the vertical direction in the unlocked state on an inner peripheral surface of the main body part 45. Portions, which are to contact the non-circular part 33 in the mounted state, of inner peripheral surfaces of the pair of support parts 47a, 47b are inclined radially outward toward one circumferential side (a clockwise direction in
The pair of arm parts 48a, 48b is provided to protrude to be substantially parallel with each other in the vertical direction in the unlocked state from two positions, which are opposite to each other in the radial direction, on the inner peripheral surface of the main body part 45. Specifically, one (upper) arm part 48a of the pair of arm parts 48a, 48b is provided to extend downward from a portion, which is adjacent to one circumferential side (clockwise direction, in
In the first example, a thickness dimension of the moveable-side lock member 43 is smaller than a depth dimension (dimension in the width direction) of the concave part 44.
Also, in the locked state, a part (a part shown with diagonal lattices in
The moveable-side lock member 43 configured as described above is arranged at an inner side of the concave part 44 of the other support plate part 22a in a state where the non-circular part 33 of the adjustment rod 17a is inserted in the support hole 50 having a substantially rectangular shape defined by the pair of support parts 47a, 47b and the pair of arm parts 48a, 48b. In this state, a radially inner end face of one (upper) support part 47a of the pair of support parts 47a, 47b is in contact with one (upper) pressing curved surface part 36a of the pair of pressing curved surface parts 36a, 36b of the non-circular part 33, and a radially inner end face of the other (lower) support part 47b is in contact with the other (lower) pressing curved surface part 36a of the pair of pressing curved surface parts 36a, 36b.
Also, a rear surface of the leading end portion of one (front) arm part 48a of the pair of arm parts 48a, 48b is in elastic contact with one (front) flat surface part 35a of the pair of flat surface parts 35a, 35b of the non-circular part 33, and a front surface of the leading end portion of the other (rear) arm part 48b is in elastic contact with the other (front) flat surface part 35a of the pair of flat surface parts 35a, 35b. Thereby, the pair of arm parts 48a, 48b is configured to elastically move toward and away from the pair of flat surface parts 35a, 35b. In this way, the moveable-side lock member 43 is supported to the adjustment rod 17a so as to be synchronously displaceable in the vertical direction and in the rotation direction. In the meantime, in the mounted state, the moveable-side lock member 43 can elastically rotate relative to the adjustment rod 17a within the elastic range of the pair of arm parts 48a, 48b.
Also, the moveable-side lock member 43 is arranged with being clamped between the outer surface (a bottom surface of the concave part 44) of the other support plate part 22b in the width direction and the inner surface of the driven-side cam 37 in the width direction. In this way, the moveable-side lock member 43 is positionally determined (retained) in the width direction. The thickness of the moveable-side lock member 43 is smaller than the depth of the concave part 44. For this reason, it is possible to form a slight gap in the width direction between the outer surface of the moveable-side lock member 43 in the width direction and the inner surface of the driven-side cam 37 in the width direction and/or between the inner surface of the moveable-side lock member 43 in the width direction and the outer surface (the bottom surface of the concave part 44) of the other support plate part 22b in the width direction. As a result, the moveable-side lock member 43 is not strongly clamped by the outer surface (the bottom surface of the concave part 44) of the other support plate part 22b in the width direction and the inner surface of the driven-side cam 37 in the width direction.
Subsequently, an operation of the position adjustment device for steering wheel of the first example is described.
When setting the steering wheel 1 to the state (locked state) where the vertical position and the position in the front and rear direction of the steering wheel 1 can be kept at positions after adjustment, the adjustment lever 23 in the state (unlocked state) where the position of the steering wheel 1 can be adjusted is caused to oscillate in a predetermine direction (in general, upward; hereinafter, referred to as ‘locking direction’). Thereby, an axial dimension of the cam device is expanded to contract an interval between the driven-side cam 37 and the pressing plate 25. As a result, a frictional force that is applied to a contact part between the outer peripheral surface of the inner column 19a and the inner peripheral surface of the outer column 18a, a frictional force that is applied to a contact part between the outer surfaces in the width direction of the pair of clamped parts 21a, 21a configuring the displacement bracket 13a and the inner surfaces in the width direction of the pair of support plate parts 22a, 22b configuring the support bracket 14a, and a frictional force that is applied between a contact part between the outer surfaces of the pair of support plate parts 22a, 22b in the width direction and the inner surfaces of the driven-side cam 37 and the pressing plate 25 in the width direction are respectively increased, and the locked state is formed.
Subsequently, an operation of the lock mechanism 39 is described.
Upon the above operation, when the adjustment rod 17a is rotated in association with the oscillation of the adjustment lever 23, the moveable-side lock member 43 is rotated in the locking direction shown in
Specifically, in the first example, the moveable-side tooth part 49 is gradually engaged with the fixed-side tooth part 42 in order from the convex portion formed at the other end portion (an end portion of a counterclockwise direction-side in
Also, in the first example, the moveable-side lock member 43 is supported to the adjustment rod 17a to be elastically rotatable within the elastic range of the pair of arm parts 48a, 48b. For this reason, even when the leading end portion of the convex portion of the moveable-side tooth part 49 and the leading end portion of the convex portion of the fixed-side tooth part 42 are contacted to each other and are thus not normally engaged with each other, the moveable-side lock member 43 is elastically displaced from this state, so that the moveable-side tooth part 49 and the fixed-side tooth part 42 can be normally engaged with each other.
Also, as described above, in the state where the moveable-side tooth part 49 and the fixed-side tooth part 42 are engaged with each other, the moveable-side lock member 43 is applied with a rotating force in the locking direction on the basis of the elastic force of the pair of arm parts 48a, 48b and a wedge effect is generated between the fixed-side tooth part 42 and one pressing curved surface part 36a and the wedge-shaped part 55, so that the moveable-side tooth part 49 is strongly pressed to the fixed-side tooth part 42.
In the meantime, in the locked state, a part, which is in contact with one pressing curved surface part 36a of the non-circular part 33, of the inner peripheral surface of one (upper) support part 47a is inclined upward toward one circumferential side (a front side in the clockwise direction in
When switching from the locked state to the unlocked state, the adjustment lever 23 is caused to oscillate in an opposite direction (generally, downward) to the predetermined direction, so that the axial dimension of the cam device is contracted to expand the interval between the driven-side cam 37 and the pressing plate 25. Thereby, each frictional force is reduced. Also, the moveable-side lock member 43 is rotated in the unlocking direction as shown in
According to the first example configured as described above, it is possible to firmly keep the vertical position of the steering wheel in the state (locked state) where the steering wheel can be kept at the position after the adjustment.
That is, in the first example, in the locked state, the fixed-side tooth part 42 provided to the other support plate part 22b of the support bracket 14a fixed to the vehicle body and the moveable-side tooth part 49 of the moveable-side lock member 43 are engaged with each other. The moveable-side lock member 43 is supported to the adjustment rod 17a so as to be synchronously displaceable in the vertical direction. For this reason, for example, even when the steering wheel 1 is applied with the upward high impact force upon a secondary collision, it is possible to prevent the steering wheel 1 from being displaced (for example, leaping up) in the vertical direction by the high keeping force based on the engagement between the fixed-side tooth part 42 and the moveable-side tooth part 49. As a result, it is possible to keep a position of an airbag inflated at the rear of the steering wheel 1 at an appropriate position, and to securely protect a driver by the airbag. Also, for example, if a downward impact load is applied to the steering wheel 1 in association with leaning against the steering wheel 1 when the driver gets in or off the vehicle, it is possible to prevent the steering wheel 1 from being displaced downward.
Also, in the first example, in the locked state, the slight gap is provided in the width direction between the outer surface of the moveable-side lock member 43 in the width direction and the inner surface of the driven-side cam 37 in the width direction or between the inner surface of the moveable-side lock member 43 in the width direction and the outer surface of the other support plate part 22b in the width direction. For this reason, the high frictional force is not generated between both side surfaces of the moveable-side lock member 43 in the width direction and the inner surface of the driven-side cam 37 in the width direction and the outer surface of the other support plate part 22b in the width direction. As a result, when switching from the locked state to the unlocked state, it is possible to prevent a situation where the moveable-side lock member 43 is difficult to rotate and the operability of the adjustment lever 23 is lowered.
Also, in the first example, in the locked state, the part, which is in contact with one pressing curved surface part 36a of the non-circular part 33, of the inner peripheral surface of one (upper) support part 47a is inclined upward toward one circumferential side (a front side in the clockwise direction in
Also, in the first example, a part of the moveable-side lock member 43 is provided with the wedge part 46 as described above, so that the part (the part shown with the diagonal lines in
In the meantime, when implementing the structure of the first example, the lock mechanism 39 may be provided to only the other (right, in
A second example of the embodiment of the present invention is described with reference to
Specifically, in the second example, a part, which is adjacent to the other long hole 15b for tilt adjustment in the front and rear direction and in the vertical direction, of an inner surface of the other support plate part 22c in the width direction is formed with a concave part 44a having a substantially rectangular shape, which is long in the vertical direction, as seen in the width direction. A front surface edge (or rear edge) of the concave part 44a is formed with the fixed-side tooth part 42 (refer to
A structure of the moveable-side lock member 43 (a detailed structure is shown in
In this state, the moveable-side lock member 43 is arranged with being clamped between the inner surface (the bottom surface of the concave part 44a) of the other support plate part 22c in the width direction and the outer surface in the width direction of the other clamped part 21a of the pair of clamped parts 21a, 21a. In this way, the moveable-side lock member 43 is positionally determined (retained) in the width direction.
In the meantime, also in the second example, since the thickness of the moveable-side lock member 43 is made smaller than the depth of the concave part 44a, it is possible to form a slight gap in the width direction between the outer surface of the moveable-side lock member 43 in the width direction and the inner surface (the bottom surface of the concave part 44a) of the other support plate part 22b in the width direction or between the inner surface of the moveable-side lock member 43 in the width direction and the outer surface of the other clamped part 21a in the width direction. As a result, the moveable-side lock member 43 is not clamped by the inner surface (the bottom surface of the concave part 44) of the other support plate part 22c in the width direction and the outer surface of one clamped part 21a in the width direction.
In the meantime, in the second example, a guide protrusion 56 arranged at the inner side of the other long hole 15b for tilt adjustment and configured to lock rotation and to guide vertical displacement of the driven-side cam 37a is formed at a radially inner end portion of the inner surface of the driven-side cam 37a in the width direction.
The other structures and operations/effects are similar to the first example of the embodiment.
A third example of the embodiment of the present invention is described with reference to
Also, in the third example, the lock mechanism 39b has a pair of moveable-side lock members 43, 43. In the third example, the pair of moveable-side lock members 43, 43 has the same shape. Specifically, one (an inner side in the width direction, a rear side in
The pair of moveable-side lock members 43, 43 configured as described above is respectively arranged at the inner side of the concave part 44b of the other support plate part 22a in the state where the non-circular part 33 of the adjustment rod 17a is inserted in the support hole 50 defined by the pair of support parts 47a, 47b and the pair of arm parts 48a, 48b. In this way, the pair of moveable-side lock members 43, 43 is supported to the adjustment rod 17a to be synchronously displaceable in the vertical direction and in the rotation direction.
In the meantime, in the third example, a thickness sum of the pair of moveable-side lock members 43, 43 is made smaller than the depth of the concave part 44b (a dimension in the width direction). For this reason, also in the locked state, it is possible to form a slight gap in the width direction between the outer surface of the other moveable-side lock member 43 in the width direction and the inner surface of the driven-side cam 37 in the width direction, between the inner surface of the other moveable-side lock member 43 in the width direction and the outer surface of one moveable-side lock member 43 in the width direction or between the inner surface of one moveable-side lock member 43 in the width direction and the outer surface (the bottom surface of the concave part 44b) of the other support plate part 22b in the width direction. As a result, the pair of moveable-side lock members 43, 43 is not strongly clamped by the outer surface (the bottom surface of the concave part 44b) of the other support plate part 22b in the width direction and the inner surface of the driven-side cam 37 in the width direction.
In the third example configured as described above, when the adjustment rod 17a is rotated in the locking direction (the counterclockwise direction, in
According to the structure of the third example, it is possible to further firmly fix the vertical position of the steering wheel 1 in the locked state, based on the engagement between the fixed-side tooth part 42 and the moveable-side tooth part 49 of one moveable-side lock member 43 and the engagement between the second fixed-side tooth part 51 and the moveable-side tooth part 49 of the other moveable-side lock member 43, as compared to the structure of the first example of the embodiment.
Also, in the third example, when the adjustment rod 17a (the steering wheel 1) is intended to be displaced upward in association with the occurrence of the secondary collision, the wedge effect is generated between the fixed-side tooth part 42 and one pressing curved surface part 36a of the non-circular part 33 and the wedge-shaped part 55 of one moveable-side lock member 43, thereby resisting the upward displacement of the adjustment rod 17a (the steering wheel 1).
Also, in the third example, if a downward impact load is applied to the steering wheel 1 in association with leaning against the steering wheel 1 when the driver gets in or off the vehicle, even though the adjustment rod 17a (the steering wheel 1) is intended to be displaced downward, the wedge effect is generated between the second fixed-side tooth part 51 and the other pressing curved surface part 36b of the non-circular part 33 and the wedge-shaped part 55 of the other moveable-side lock member 43, thereby resisting the downward displacement of the adjustment rod 17a (the steering wheel 1).
The other structures and operations/effects are similar to the first example of the embodiment.
A fourth example of the embodiment of the present invention is described with reference to
In a lock mechanism 39c configuring the position adjustment device for steering wheel of the fourth example, a front surface of a concave part 44c formed on the outer surface of the other support plate part 22b in the width direction is not formed with the fixed-side tooth part 42 of the first example of the embodiment, and is instead formed with a fixed-side friction surface 52 parallel with the formation direction (vertical direction) of the other long hole 15b for tilt adjustment. In the fourth example, the fixed-side friction surface 52 corresponds to the fixed-side engagement part defined in the claims. In the meantime, the fixed-side friction surface 52 is formed to be flat and may also be subjected to a surface treatment for increasing a friction coefficient of a surface. As the surface treatment, for example, roughening processing (shot blasting, knurling processing and the like) may be performed to increase a surface roughness of the fixed-side friction surface 52 or the fixed-side friction surface 52 may be coated with a friction agent. The friction agent is not particularly limited inasmuch as it can increase the friction coefficient of the fixed-side friction surface 52.
Also, the moveable-side lock member 43a is provided with a moveable-side friction surface 53, instead of the moveable-side tooth part 49 of the moveable-side lock member 43 of the first example of the embodiment. In the fourth example, the moveable-side friction surface 53 corresponds to the moveable-side engagement part defined in the claims.
Specifically, in the fourth example, the moveable-side friction surface 53 is formed to have a curved surface shape of which a center is a center O53 located at the rear (a right side, in
In the meantime, the moveable-side friction surface 53 may also be configured by a smooth curved surface or may be subjected to a surface treatment for increasing a friction coefficient of the surface. As the surface treatment, the similar treatment to the fixed-side friction surface 52 may be adopted.
In the fourth example, both the member (in the fourth example, the other support plate part 22b) having the fixed-side friction surface 52 and the member (in the fourth example, the moveable-side lock member 43a) having the moveable-side friction surface 53 are made of iron-based alloy such as carbon steel.
Also in the fourth example, when the adjustment rod 17a is rotated in association with the oscillation of the adjustment lever 23, the moveable-side lock member 43a is rotated from the state shown in
In the meantime, the member (the support bracket 14a) having the fixed-side friction surface 52 may be made of a metal material having hardness lower than the metal material of the member (the moveable-side lock member 43a) having the moveable-side friction surface 53. For example, the other support plate part 22b is made of aluminum alloy, and the moveable-side lock member 43a is made of iron-based alloy such as carbon steel. When this configuration is adopted, it is possible to cause the moveable-side friction surface 53 to bite the fixed-side friction surface 52, in the locked state.
Also, when the fixed-side friction surface 52 is formed on other member (for example, a plate-shaped member or the like), which is a separate member from the other support plate part 22b and is fixed (for example, welded) to the other support plate part 22b, the other support plate part 22b may be made of iron-based alloy such as carbon steel, and only the other member may be made of aluminum alloy. When this configuration is adopted, it is possible to achieve the above-described effects while securing the stiffness of the support bracket 14a.
Also, the moveable-side tooth part 49 of the first example of the embodiment may be formed, instead of the moveable-side friction surface 53. When this configuration is adopted, it is possible to easily cause the moveable-side tooth part 49 to bite the fixed-side friction surface 52.
Also, a structure where the pair of moveable-side lock members is combined with phases thereof being offset by 180° may be adopted, like the third example of the embodiment. In this case, the fixed-side friction surface is provided on both the front and rear surfaces of the concave part 44c.
The structure of the fourth example can be appropriately applied to the structure of each example of the embodiment.
The other structures and operations/effects are similar to the first example of the embodiment.
A fifth example of the embodiment of the present invention is described with reference to
In the fifth example, a structure of the position adjustment device for steering wheel having a lock mechanism for increasing the force of keeping the position in the front and rear direction of the steering wheel 1 in the locked state is provided.
Specifically, in the fifth example, a displacement bracket 13b having a substantially U-shaped section and formed by bending a metal plate having sufficient stiffness is fixed to the front end portion of the outer column 18b clamped between the pair of support plate parts 22a, 22b of the support bracket 14a (refer to
Also, a pair of clamped parts 21b, 21c configuring the displacement bracket 13b is formed with through-holes 16c, 16d for telescopic adjustment extending in the axial direction (the front and rear direction), respectively. In the fifth example, each of the through-holes 16c, 16d for telescopic adjustment corresponds to the long hole for adjustment defined in the claims, and the front and rear direction corresponds to the position adjustment direction.
Also, portions, which are adjacent to the through-hole 16d for telescopic adjustment in the front and rear direction and in the vertical direction, of outer surfaces of the pair of clamped parts 21b, 21c in the width direction are formed with concave parts 54a, 54b that are long in the front and rear direction.
Also, in the fifth example, the pair of clamped parts 21b, 21c is provided with lock mechanisms 39d, 39e, respectively.
In the below, the lock mechanism 39d provided to one (right) clamped part 21b of the pair of clamped parts 21b, 21c is described. In the fifth example, since a structure of the lock mechanism 39e provided to the other clamped part 21c of the pair of clamped parts 21b, 21c is similar to the lock mechanism 39d provided to one clamped part 21b, the description thereof is omitted.
The lock mechanism 39d is configured by a fixed-side tooth part 42a, the moveable-side lock member 43, and the non-circular part 33 provided to the adjustment rod 17a.
The fixed-side tooth part 42a is provided on an outer surface of one clamped part 21b in the width direction, and is configured by a concave-convex part formed in the formation direction (vertical direction) of the through-hole 16d for telescopic adjustment.
Specifically, in the fifth example, a lower surface of the concave part 54a formed on one (right) clamped part 21b is formed with the fixed-side tooth part 42a. In the meantime, although not shown, an upper surface of a lower frame part configuring a frame member having a rectangular frame shape, which is provided separately from one clamped part 21b and is long in the front and rear direction, may be formed with the fixed-side tooth part 42a, and the frame member may be fixed to an inner side of the concave part 54a.
The moveable-side lock member 43 has a similar structure to the moveable-side lock member 43 of the first example of the embodiment, in which the moveable-side lock member 43 is arranged with being rotated rearward by about 90° (so that the moveable-side lock member 43 is engaged with the fixed-side tooth part 42a formed on the lower surface of the concave part 54a, in the locked state) with respect to the arrangement aspect of the first example of the embodiment. Since the other structure of the moveable-side lock member 43 is similar to the first example of the embodiment, the detailed description thereof is omitted.
The moveable-side lock member 43 is arranged at the inner side of the concave part 54a of the other support plate part 22a in the state where the non-circular part 33 of the adjustment rod 17a is inserted in the support hole 50 defined by the pair of support parts 47a, 47b and the pair of arm parts 48a, 48b. In the meantime, in the fifth example, a part, which is arranged at the inner side of the moveable-side lock member 43 of one lock mechanism 39d, of the adjustment rod 17a and a part, which is arranged at the inner side of the moveable-side lock member 43 of the other lock mechanism 39e, are provided with the non-circular parts 33, 33. The non-circular parts 33 may be formed to be continuous or to be spaced from each other in the axial direction of the adjustment rod 17a.
In the fifth example configured as described above, when the adjustment rod 17a is rotated in association with the oscillation of the adjustment lever 23 upon the switching from the unlocked state to the locked state, the moveable-side lock member 43 is rotated from a state shown in
In the fifth example configured as described above, it is possible to firmly fix the position in the front and rear direction of the steering wheel 1 in the locked state by the concave-convex engagement between the fixed-side tooth part 42a and the moveable-side tooth part 49. As a result, in the locked state, when the high impact force is applied to the steering wheel 1 in the front and rear direction, it is possible to firmly keep the position of the steering wheel 1.
In the meantime, the structure where the pair of moveable-side lock members is offset by 180°, like the third example of the embodiment, or the structure where the fixed-side and moveable-side friction surfaces are friction-engaged, like the fourth example of the embodiment, may be applied to the structure of the fifth example. Also, a structure where only one clamped part 21b (21c) of the pair of clamped parts 21b, 21c is provided with the lock mechanism (a structure where any one of the lock mechanisms 39d, 39e is omitted) may be adopted. Also, a structure where the lock mechanisms 39d, 39e of the fifth example are provided at the inner sides of the pair of clamped parts 21b, 21c in the width direction may be adopted.
The other structures and operations/effects are similar to the first example of the embodiment.
The structures of the respective examples of the embodiment can be appropriately combined and implemented within a range in which the technical inconsistency is not caused. When applying the structures of the first example to the fourth example of the embodiment to the structure of the lock mechanism for increasing the force of keeping the position in the front and rear direction of the steering wheel, like the fifth example of the embodiment, the descriptions of the respective directions (the front and rear direction and the vertical direction) are appropriately changed and interpreted.
Also, the present invention can be applied to not only a structure where both the tilt mechanism for adjusting the vertical position of the steering wheel and the telescopic mechanism for adjusting the position in the front and rear direction are provided but also a structure where only the tilt mechanism or only the telescopic mechanism is provided.
Also, the displacement bracket may be provided below the outer column or above the outer column.
Also, the expansion/contraction mechanism can adopt not only the cam device but also a screw-type structure configured to adjust a tightening amount of the adjustment nut screwed to the male screw part provided on the adjustment rod, based on the oscillation of the adjustment lever.
The subject application is based on Japanese Patent Application No. 2016-078330 filed on Apr. 8, 2016, the contents of which are incorporated hereby by reference.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2016-078330 | Apr 2016 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2017/014348 | 4/6/2017 | WO | 00 |
