This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2016-063037, filed on Mar. 28, 2016, the entire contents of which are incorporated herein by reference.
The present invention relates to a steering column device capable of telescopic operation.
As a conventional steering column device, there has been one including a vehicle-body attachment bracket configured to be fixed to a vehicle body, a pair of sidewalls provided to extend downward from this vehicle-body attachment bracket, and a steering column disposed between this pair of sidewalls (see Patent Literature 1: WO2012/000593A1, for example).
The steering column in Patent Literature 1 includes an outer column fixed to the vehicle-body side, an inner column arranged to be movable inside the outer column in the axial direction (vehicle longitudinal direction), and a fastener configured to fasten the inner column to the outer column. A restricting member placed on the inner column comes into contact with a locking member placed on an operating shaft for the fastener to thereby define the range of movement of the inner column (telescopic-position adjustment range).
Moreover, in a collision of the vehicle, a load of a preset value or greater may be applied to the restricting member, and a locking plate engaging with the locking member may fracture the restricting member. This fracture allows the inner column to move forward to the outside of the telescopic movement range.
Meanwhile, in Patent Literature 1, the restricting member is fractured in the middle of contraction of the inner column. This leads to a problem that the impact absorption load abruptly increases in the middle of absorption of the impact energy in the collision of the vehicle.
Thus in view of the above circumstance, an object of the present invention is to provide a steering column device that suppresses abrupt increase in impact absorption load in the middle of absorption of impact energy.
A steering column device according to the present invention includes: an outer column having a tubular shape and arranged along a vehicle longitudinal direction; an inner column inserted in the outer column in such a way as to be movable in a tube-axis direction and capable of telescopic operation; a restricting member provided through a tubular wall at a lower section of the outer column in such a way as to be capable of coming in and out of the tubular wall in a thickness direction thereof, and configured to restrict a front-end position of the inner column in a direction of telescopic contraction thereof with a stopper part; and a load absorbing wire including a first end engageable with the restricting member and a second end supported on the inner column side, and configured to be deformed by movement of the second end toward a vehicle front side together with the inner column upon application of a load of a preset value or greater to the inner column toward the vehicle front side, to thereby absorb the load. The stopper part of the restricting member is normally disposed to project to a radially inner side of an inner peripheral surface of the tubular wall of the outer column. The stopper part of the restricting member is capable of being moved by the load absorbing wire to a position on a radially outer side of the inner peripheral surface of the tubular wall of the outer column when the load absorbing wire is deformed upon application of a load of a preset value or greater to the inner column toward the vehicle front side.
In the steering column device according to the present invention, when the inner column moves toward the vehicle front side in a collision of the vehicle, the stopper part of the restricting member sinks to a radially outer side of the inner peripheral surface of the tubular wall of the outer column. In this way, the front end of the inner column can avoid contact with the stopper part of the restricting member and move toward the front side beyond the stopper part. This makes it possible to suppress abrupt increase in impact absorption load in the middle of absorption of the impact energy.
Some embodiments of the present invention will be described below with reference to the drawings. Note that, in the drawings, FR denotes a vehicle front side and RR denotes a vehicle rear side.
As illustrated in
The steering column device 1 further includes: a locking mechanism 60 configured to fasten the attachment bracket 2, the outer column 7, and the inner column 9; an energy absorbing mechanism 61 configured to absorb impact energy in a secondary collision; and a telescopic-position restricting mechanism 62 configured to define an adjustment range for the position of the inner column 9 relative to the outer column 7 in the vehicle longitudinal direction (telescopic position).
The inner column 9 is configured to be inserted in the outer column 7 in such a way as to be movable in the tube-axis direction, thereby allowing telescopic operation. Specifically, in a locked state, the front-rear position of the inner column 9 relative to the outer column 7 is locked (fixed) by a locking member 68. In an unlocked state, an operating lever 15 is pushed down, so that the lock is released and the front-rear position of the inner column 9 relative to the outer column 7 can be changed. Then, after the front-rear position of the inner column 9 is set to a proper position, the operating lever 15 is pushed up and locked, so that the front-rear position of the inner column 9 relative to the outer column 7 is fixed.
The attachment bracket 2 includes a front fixing part 3 and a rear fixing part 5 configured to be fixed to the vehicle body's steering member (not illustrated). The front fixing part 3 includes a pivot portion 17 configured to pivotally support the outer column 7 such that the outer column 7 can be swung, and the rear fixing part 5 includes a pair of hanging portions hanging from its right and left edges. Both hanging portions are provided with a tilt slot bored to define a tilt-position adjustment range along the vehicle vertical direction (tilt direction). The tilt slot is formed of an elongated hole arched about the pivot portion.
The outer column 7 is formed in a tubular shape and arranged between the pair of hanging portions of the attachment bracket 2 along the vehicle longitudinal direction. The outer column 7 has its front end portion pivotally supported to the pivot portion 17 of the front fixing part 3 of the attachment bracket 2 with a bolt. In this way, the rear end side of the outer column 7 can swing in the vehicle vertical direction.
Moreover, as illustrated in
As illustrated in
A pair of guiderail supporting parts 65 are provided to extend downward from front end portions of the opposite edges of the slit 55 extending along the tube-axis direction, and a supporting pin 66 is laid between the guiderail supporting parts 65. A later-described guiderail 67 is swingably supported on the supporting pin 66. A pair of stopper parts 31 are provided to extend downward on the rear side of the guiderail supporting parts 65, and a later-described restricting member 11 is held between the stopper parts.
The inner column 9 is formed in a tubular shape and inserted in the tube of the outer column 7 in such a way as to be movable in the tube-axis direction. A steering shaft 10 is rotatably supported inside the tubes of the inner column 9 and the outer column 7. The steering shaft 10 includes a lower shaft 10L housed in the outer column 7 and an upper shaft 10U housed in the inner column 9. The upper shaft 10U and the lower shaft 10L are coupled to each other with a spline(s). Thus, the upper shaft 10U and the lower shaft 10L can rotate together about an axis, and the upper shaft 10U can move relative to the lower shaft 10L in the direction of the axis.
As illustrated in
The operating shaft 64 has a shaft shape, penetrates through the tilt slots in both hanging portions of the attachment bracket 2 and both clamp parts 63 of the outer column 7 along the vehicle width direction, and is supported to the clamp parts 63 in such a way as to be turnable about its axis.
The operating lever 15 is disposed on the operating shaft 64.
The front end of the guiderail 67 is pivotally supported to the guiderail supporting parts 65, provided on the outer periphery of the outer column 7, with the supporting pin 66 such that the guiderail 67 can be swung, while the rear end side is held between the locking member 68 and the cam member 57. In this case, the cam member 57 presses the locking member 68 against the locked member 69 via the guiderail 67. With such a configuration, a force (frictional force) in the direction of rotation of the cam member 57 is not transmitted to the locking member 68, and only a force in the radial direction is transmitted to the locking member 68. In this way, the inner column 9 can be fixed without being displaced in the tube-axis direction from the desired position when a locking operation is performed.
As illustrated in
The wire-member catching part 70 is a recess provided in the upper surface of the locking member 68, and supports a second end 49 of a load absorbing wire 13.
As illustrated in
As illustrated in
As illustrated also in
The above load absorbing wire 13 is curved in a J-shape in a side view. Specifically, the load absorbing wire 13 is integrally formed of: a pair of right and left main parts 41 extending straight in the vehicle longitudinal direction substantially in parallel to the outer column 7; bent parts 43 (first ends 45) formed in L-shapes in a plan view and bent outward in directions crossing the outer column 7 from the front ends of the main parts 41 on the vehicle front side; curved parts 47 formed in a U-shape in the side view and curved upward from the rear ends of the main parts 41 on the vehicle rear side; and the second end 49 extending toward the vehicle front side from the curved parts 47 with the tips formed integrally with each other in the vehicle width direction. Note that the second end 49 of the load absorbing wire 13 is fixed to the inner column 9 by the wire-member catching part 70 during the locked state. Also, at the lower section of the outer column 7, a wire holding part 51 protruding downward is provided. In the wire holding part 51, notches 53 are formed with their vehicle rear sides open to be capable of housing the bent parts 43 of the load absorbing wire 13. Further, as illustrated in
Next, movement of the restricting member 11 in a collision of the vehicle will be described with reference to
As illustrated in
As illustrated in
Advantageous effects by the first embodiment will be described below.
(1) The steering column device 1 according to the first embodiment includes: the outer column 7 having a tubular shape and arranged along the vehicle longitudinal direction; the inner column 9 inserted in the outer column 7 in such a way as to be movable in the tube-axis direction and capable of telescopic operation; the restricting member 11 provided through the tubular wall 21 at the lower section of the outer column 7 in such a way as to be capable of coming in and out of the tubular wall 21 in the thickness direction thereof, and configured to restrict the front-end position of the inner column 9 in the direction of telescopic contraction thereof with the stopper part 31; and the load absorbing wire 13 including the first ends 45 engageable with the restricting member 11 and the second end 49 supported on the inner column 9 side, and configured to be deformed by movement of the second end 49 toward the vehicle front side together with the inner column 9 upon application of a load of the preset value or greater to the inner column 9 toward the vehicle front side, to thereby absorb the load.
The stopper part 31 of the restricting member 11 is normally disposed to project to a radially inner side of the inner peripheral surface 59 of the tubular wall 21 of the outer column 7, and the stopper parts 31 of the restricting member 11 are capable of being moved by the load absorbing wire 13 to a position on a radially outer side of the inner peripheral surface 59 of the tubular wall 21 of the outer column 7 when the load absorbing wire 13 is deformed upon application of a load of the preset value or greater to the inner column 9 toward the vehicle front side.
Thus, when the inner column 9 moves toward the vehicle front side in a collision of the vehicle, the stopper part 31 of the restricting member 11 sinks below (radially outer side of) the inner peripheral surface 59 of the tubular wall 21 of the outer column 7. In this way, the front end of the inner column 9 can avoid contact with the stopper part 31 of the restricting member 11 and move toward the front side beyond the stopper part 31. This makes it possible to suppress abrupt increase in impact absorption load in the middle of absorption of the impact energy.
(2) The restricting member 11, with which the first ends 45 of the load absorbing wire 13 engage, includes the wire push surfaces 26.
Thus, when the first ends 45 of the load absorbing wire 13 move toward the vehicle rear side upon application of a load of the preset value or greater to the inner column 9 toward the vehicle front side, the first ends 45 of the load absorbing wire 13 can push down the wire push surfaces 26 of the restricting member 11. Hence, the restricting member 11 can be forcibly released from the wire holding part 51 of the outer column 7. This makes it possible to further suppress abrupt increase in impact absorption load in the middle of absorption of the impact energy.
Next, a second embodiment will be described with reference to
A restricting member according to the second embodiment is such that the wire push surfaces of its lower holding part are formed as inclined surfaces.
As illustrated in
Next, movement of the restricting member 111 in a collision of the vehicle will be described with reference to
As illustrated in
As illustrated in
An advantageous effect by the second embodiment will be described below.
The restricting member 111, with which the first ends 45 of the load absorbing wire 13 engage, includes the inclined surfaces 126, which extend obliquely upward toward the rear side relative to the tube-axis direction of the outer column 7 in a side view.
Thus, when the first ends 45 of the load absorbing wire 13 move toward the vehicle rear side upon application of a load of the preset value or greater to the inner column 9 toward the vehicle front side, the bent parts 43 (first ends 45) of the load absorbing wire 13 push down the inclined surfaces 126 of the restricting member 111. Accordingly, the bent parts 43 of the load absorbing wire 13 can push down the restricting member 111 to a greater extent.
Next, a third embodiment will be described with reference to
A load absorbing wire according to the third embodiment is such that its first ends 45 (front ends) are bent in a V shape in a side view.
Specifically, as illustrated in
Next, movement of the restricting member 11 in a collision of the vehicle will be described with reference to
As illustrated in
As illustrated in
An advantageous effect by the third embodiment will be described below.
(1) The bent parts 243 formed in the V shape in a side view are provided at the first ends 45 of the load absorbing wire 13.
Thus, when the first ends 45 of the load absorbing wire 13 move toward the vehicle rear side upon application of a load of the preset value or greater to the inner column 9 toward the vehicle front side, the bent parts 243 at the first ends 45 of the load absorbing wire 13 push down the restricting member 11. Accordingly, the bent parts 243 at the first ends 45 of the load absorbing wire 13 can push down the restricting member 11 to a greater extent.
Next, a fourth embodiment will be described with reference to
As illustrated in
The upper part 313 includes a catching part 317 provided on the lower side, and a stopper part 319 provided on the catching part 317. The stopper part 319 normally projects to a radially inner side (upper side in
The lower part 315 is a member bent in an L-shape in a side view with a front leg part 321 extending toward the front side and a lower leg part 323 extending downward from the rear end of the front leg part 321, and is pivotally supported at its middle part to the outer column 7 via a turn shaft portion 325 such that the lower part 315 can turn. Also, at the lower end of the lower leg part 323, a wire hook portion 327 is formed which is recessed upward. The first ends 45 of the load absorbing wire 13 are inserted and caught in this wire hook portion 327.
Next, movement of the restricting member 311 in a collision of the vehicle will be described with reference to
As illustrated in
When a load of the preset value or greater is applied to the inner column 9 toward the vehicle front side in a collision of the vehicle, the inner column 9 moves toward the front side together with the locking member 68 and the second end 49 of the load absorbing wire 13. Then, the main parts 41 of the load absorbing wire 13 turn counterclockwise in the side view about the cam member 57 such that the front ends (first ends 45) sink, and the load absorbing wire 13 moves rearward.
Since the front ends (first ends 45) of the load absorbing wire 13 are caught in the wire hook portion 327 of the lower part 315 of the restricting member 311, the lower part 315 turns counterclockwise about the turn shaft portion 325 with the rearward movement of the load absorbing wire 13.
Consequently, as illustrated in
An advantageous effect by the fourth embodiment will be described below.
The restricting member 311 includes the upper part 313 provided at its upper end with the stopper part 319 configured to project to a radially inner side of the tubular wall 21 of the outer column 7, and the lower part 315 configured to be turnable with the first ends 45 of the load absorbing wire 13 caught thereon.
When the first ends 45 of the load absorbing wire 13 move toward the vehicle rear side upon application of a load of the preset value or greater to the inner column 9 toward the vehicle front side, the lower part 315 turns about the turn shaft portion 325 to push down the upper part 313. In this way, the first ends 45 of the load absorbing wire 13 can push down the stopper part 319 of the restricting member 311 to a greater extent.
It is to be noted that the present is not limited to the above-described embodiments but various changes and the like can be made thereto.
Number | Date | Country | Kind |
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2016-063037 | Mar 2016 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
8894097 | Sulser | Nov 2014 | B2 |
9623896 | Uesaka | Apr 2017 | B2 |
20030160440 | Kahlenberg | Aug 2003 | A1 |
20080236326 | Matsui | Oct 2008 | A1 |
20110175335 | Takezawa | Jul 2011 | A1 |
20120112443 | Arakawa | May 2012 | A1 |
20130118292 | Sulser | May 2013 | A1 |
20160159387 | Okano | Jun 2016 | A1 |
20160280248 | Uesaka | Sep 2016 | A1 |
20170274922 | Uesaka | Sep 2017 | A1 |
Number | Date | Country |
---|---|---|
3072779 | Sep 2016 | EP |
2005-001517 | Jan 2005 | JP |
2012000593 | Jan 2012 | WO |
Entry |
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Extended European search report dated Aug. 8, 2017 in the counterpart European patent application. |
Number | Date | Country | |
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20170274923 A1 | Sep 2017 | US |