JPH0712216Y2 - Shock absorption steering device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a steering device having a shock absorbing function, particularly a column and a steering shaft, for protecting a driver from an obstacle in a vehicle collision, in a vertical direction of the vehicle. The present invention relates to a shock absorbing steering device in a telescopic / tilt type steering device in which an angle can be adjusted with respect to the axial direction, and the telescopic / tilt type steering device can be extended and contracted.

[Prior art]

Conventionally, as a shock absorbing steering device having a tilt mechanism, for example, as shown in JP-A-60-127285, a bellows type or a tearing deformation is formed between a tightening bolt of a distance bracket and a hooking claw portion at a lower portion of a column. A device equipped with an impact energy absorber having a possible shape has been proposed. The configuration of this conventional example will be described with reference to FIGS. 6 to 9. A pair of column brackets 21 are fixed to the vehicle body portion 10 by mounting portions 21t so as to face the main body 21h, and tilting slots 21a are vertically formed in the lower half of the main body 21h of the bracket 21. The distance bracket 22 fixed to the lower surface of the column 6 is held by the main body 21h. A U-shaped notch 22u opened rearward (handle side) is formed facing both side walls 22k of the distance bracket 22, and a tightening bolt 23 is provided so as to penetrate the notch 22u and the tilt elongated hole 21a. The nut portion 24n of the tilt lever 24 is screwed into the threaded portion of the bolt 23, and this tightening causes the distance bracket 22 to move to the column bracket 21.
It is designed to be pressed and fixed with. The portion of the tightening bolt 23 that comes into contact with the head portion 23t of the rod portion 23b has a rectangular cross section within a dimension range slightly smaller than the thickness of the column bracket 21, and is in contact with the inner surface of the tilting slot 21a. When tightened by the tilt lever 24, it serves as a rotation stopping portion 23s for the tightening bolt 23.

The shock energy absorber 25 has a corrugated or bellows-like flat plate structure, and a side wall 25k having holes for tightening bolts 25a is provided upright to face both ends of one end of the flat plate structure, and the other end thereof is erected. In the center, there is formed a long hole 25n for hooking which is hooked to the hooking claw 26 formed on the lower surface of the column 6, and the center part is an energy absorbing part 25e formed in a corrugated shape. It is locked between the tightening bolt 23 and the hook 26.

When there is a collision of the vehicle, the driver's body impacts against the steering wheel 1 due to the recoil, so that the collapsible steering shaft 2 starts collapsing and the end surface of the steering wheel 1 hits the upper end surface of the column 6. , The column 6 is pushed forward and downward. At this time, the distance bracket 22 fixed to the column 6 has the tightening bolt 23 fitted in the U-shaped notch 22u opening to the rear, so that the slippage between the column bracket 21 and the column bracket 21 is prevented. Absent. Subsequently, the hooking claw 26 that advances together with the column 6 comes into contact with the front surface of the locking elongated hole 25n of the energy absorber 25, so that the energy absorber that is connected to the tightening bolt 23 at the tightening bolt hole 25a. 25 is an energy absorbing portion having a waveform as shown in FIG.
25e is stretched, and its plastic deformation absorbs impact energy.

[Problems to be solved by the device]

The impact energy absorbing steering device for the tilt mechanism described above is more effective than the type in which the energy absorbing portion is provided between the vehicle body and the column bracket (for example, Japanese Laid-Open Patent Publication No. 55-68471). W, when a distance between the mounting flange of the column bracket and the tightening bolt is L, a large moment load of W × L does not act on the column detaching portion, that is, the column bracket 21t, so that the maximum peak load can be reduced. Although it has the advantage of reducing the impact load that the driver receives, the distance bracket 22
If it is simply locked between the tightening bolt 23 and the hook 26 on the column 6 side, a rubbing noise or an impact noise is generated due to vibration of the vehicle body during traveling. Further, since the corrugated plate-shaped member is stretched under impact load to absorb energy, it is difficult to obtain desired energy absorption characteristics.

In particular, it is difficult to obtain an energy absorption load immediately after impact, which has a small absorption load, and then gradually increases the load along a desired curve, in accordance with the absorption characteristics. Since the corrugated energy absorber has no means for regulating the plastic deformation state, there is a problem that the plastic deformation resistance of the energy absorber is hardly constant with respect to the moving stroke of the column.

[Means for Solving the Problems]

The present invention has a steering column that rotatably supports a steering shaft, a distance bracket fixed to the column, and a column bracket that fixes the column to the vehicle body via the distance bracket. In a steering device having an engaging structure in which a shaft is expandable and contractible in an axial direction and capable of transmitting rotation, and a front portion of the steering column is supported so as to be tiltable with respect to a vehicle body, a front end portion of the steering device is close to a front edge of the column bracket. An upper side portion which is fixed to the column and extends from the front end portion to a U-shaped bent portion at a midway position is in contact with a lower portion of the column and extends forward, and is gradually widened from the U-shaped bent portion to the front end portion, The rear end of the lower side is attached to the tightening bolt inserted from the column bracket to the distance bracket through the long hole. And curling plate, which is binding,
And a curling plate bent portion restricting guide member that is fixed to the column side to accommodate the curling plate and restrain the lower side of the U-shaped bent portion, and the tightening bolt insertion hole formed in the distance bracket is A laterally elongated notched groove that is open to the rear and has a length exceeding at least the expansion / contraction stroke of the steering shaft and the steering column, and the long hole at the rear end of the curling plate corresponds to the expansion / contraction stroke of the steering column. The curling plate is formed to have a length, and the U-shaped bent portion is plastically deformed and moved to absorb impact energy while being restrained by the column lower side portion and the guide member at the time of impact.

[Action]

In the present invention, when a collision occurs, the steering column and the curling plate are locked by a certain amount of movement of the steering column, the curling plate moves diagonally downward together with the steering column, and is regulated by the curling plate bent portion regulation guide member. While being subjected to plastic deformation, it absorbs impact energy. The plastically deformed portion of the curling plate, that is, the U-shaped bent portion is restrained between the column and the guide member so that the vertical bulging is restricted, and the plastic deformation progresses at a constant rate in the longitudinal direction of the curling plate.
Further, since the width of the curling plate gradually increases in the longitudinal direction toward the plastic deformation progress side, the deformation load gradually increases as the plastic deformation portion moves, and the impact force given to the driver is almost constant. Can be maintained to provide greater energy absorption. Further, since the column and the steering shaft each have a telescopic structure, driving operability is improved in combination with the tilt structure.

〔Example〕

Next, the present invention will be described by way of examples with reference to the drawings.

The tilt mechanism of the steering apparatus applied to the present embodiment is substantially the same as that described in the conventional example of FIGS. 6 and 7, and the same components are denoted by the same reference numerals and detailed description thereof is omitted. The description is omitted. Figure 2 (a), (b)
2, the steering shaft 2 which is inserted into the steering column 6 and is rotatably supported by the column is separated into an upper shaft 2a on the steering wheel side and a lower shaft 2b on the steering gear side. The ends of the two are telescopically engaged with each other by the spline groove 2c, which causes the upper shaft 2a to
2b can be expanded and contracted in the axial direction. The lower end 6a of the steering column 6 on the steering gear side is inserted into the lower bracket 40, and an elastic spherical bush 41 is interposed between the inner peripheral part of the lower bracket and the outer peripheral part of the lower end of the column. 42 is a cross joint. The column 6 can be expanded and contracted with respect to the lower bracket 40 together with the upper shaft 2a of the steering shaft 2 within a range where it does not come out of the lower bracket 40, and the column can be tilted about the spherical bush 41.
The spherical bush 41 is adapted to absorb the movement of the column during the tilting movement and the axial expansion / contraction movement (telescopic movement). The expansion and contraction operations of the steering shaft 2 and the column 6 are performed manually by overcoming the frictional force in the expansion and contraction portion, and are held at the desired length position by the frictional force.

As shown in FIG. 1, the curling plate 30 of the present embodiment has one end (rear end) formed in a U shape, and the U shape portion 30
Long holes 31 extending in the plate longitudinal direction are formed in both arm portions of a. The long hole 31 is formed to have a length substantially equal to the expansion / contraction stroke of the steering shaft 2 and the steering column 6 described above. The other end (front end) of the curling plate 30 is U-shaped so as to be fixed to the side of the steering column as will be described later, and the middle part from the front end to the rear end is formed. It is folded back in a U shape. The portion from the U-shaped bent portion 32 to the U-shaped portion 30b at the other end is the plastically deformable portion 30c. Plastic deformation part 30
c has a width of b ₂ in the portion adjacent to the U-shaped portion 30b of the other end becomes the middle of the folded portion width of the (U-shaped bent portion 32) in b ₁ is subtracted therefrom width gradually, wherein To the U-shaped portion 30a at the rear end have the same width dimension.

Referring to FIG. 2 (a), the distance bracket 33 fixed to the steering column 6 has a notch groove 33a which is notched in parallel to the column 6 from both sides toward the rear side edge from the center. is doing. The groove length of the notch groove 33a is at least the steering shaft 2 and the steering column 6.
It has a length exceeding the expansion and contraction stroke, and the tightening bolt 23, which will be described later, does not come out of the notch groove 33 even when the shaft 2 and the column 6 are maximally extended by the telescopic operation. Further, the notch groove 33 of the distance bracket 33 is provided in the column bracket 21 attached to the vehicle body portion 10 so as to sandwich the distance bracket 33 from the outside.
A tilting long hole 21a extending vertically that intersects a is formed,
The tightening bolts 23 inserted into the cutout grooves 33a and the tilting long holes 21a are provided in the U-shaped portion at the rear end of the curling plate 30.
The nut portion of the tilt lever (not shown) is inserted into the long hole 31 of the 30a and further attached to the tip of the tightening bolt 23 (see FIG. 7).
Are screwed together. In a normal state where collision does not occur, the tightening bolt 23 is inserted so that the long hole 31 of the curling plate 30 contacts the front side edge portion of the long hole, and in this state, the U-shaped portion 30b at the front end of the plate 30 is As shown in FIG. 2 (a), it is fixed to the column 6 by welding or the like in the vicinity of the front edge of the column bracket 21.

A curling plate curving portion regulation guide member 34 having a U-shape in the illustrated embodiment is secured to the curling plate 30 at both sides of the column 6 at the position of the plastically deforming portion 30c by a welding material so as to embrace the curling plate 30. ing. The lower side portion 30d connected to the U-shaped portion 30a at the rear end of the curling plate 30 is in contact with the guide member 34, and the upper side portion, that is, the plastic deformation portion 30c is in contact with the lower side portion of the column 6, Thus, the curling plate 30 is regulated so that the curvature radius R of the bent portion and the interval T between the lower side portion 30d and the plastic deformation portion 30c are kept constant.

In such a configuration, when the vehicle collides, the column 6 and the curling plate 30 are caused by a so-called secondary collision.
Moves together with the distance bracket 33 with respect to the tightening bolt 23 in the range of the long hole 31 of the plate. Due to the further applied impact, the notch groove 33a of the distance bracket 33 moves out from the tightening bolt 23 and moves forward, and at the same time, the curling plate 30 has the U-shaped portion 30b at the front end of the column 6 due to the movement of the column 6 in the same direction. The elastically deformed portion 30c is deformed while absorbing the energy of impact and extends forward, so that the U-shaped bent portion 32 comes close to the U-shaped portion 30d at the front end of the plate. FIG. 3 shows the state at this time.

During the deformation of the plastic deformation portion 30c, as described above, the curling plate bending portion regulating guide member 34 is used to make the U-shaped bending portion.
Although the curvature of 32 does not change, the width of the curling plate is the minimum width (b ₁ ) at the U-shaped bent part before the collision, and the width gradually increases as the bent part 32 moves to the front end of the plate. Therefore, the absorption of the collision energy is surely and stably absorbed at a desired increase rate defined by the increase in the width and length dimensions of the curling plate 30.

In the embodiment described above, the curling plate 30 during plastic deformation is used.
Although the curvature of the U-shaped bent portion 32 is constant and the width of the plastically deformable portion 30c of the plate is changed to gradually increase the deformation load, the present invention is not limited to such a form. Instead, the lower surface of the bent portion regulation guide member 34 is inclined in the longitudinal direction of the column 6 (so that the front side is widened), and the radius of curvature R of the curling plate is large at the initial stage of the collision so that R decreases as the deformation proceeds. It may be regulated, and thereby the deformation load may be gradually increased. The bent portion regulating guide member 34 is separately fixed to the column 6, and the front end of the distance bracket 35 is fixed to the column 6 as in the embodiment of FIG.
It is also possible to extend along the lower surface of this and use this portion as the guide portion 36 for curling plate regulation. Its shape is also fourth
The shape is not limited to the U shape as shown in the figure. The fixing means for fixing the curling plate, the distance bracket, or the bent-section restricting guide member and the steering column is not limited to welding but may be fixed by bolting or the like.

[Effect of device]

As described above, the present invention includes a steering column,
The column bracket is fastened to the vehicle body by tightening the distance bracket and the tightening bolts fixed to the column, and the tightening is released by a tilt lever having a nut portion screwed with the tightening bolt, and the column is moved in the vertical direction of the vehicle body. In the tilt steering device in which the angle can be adjusted, a curling plate constrained by a guide member for controlling a bent portion is provided between the tightening bolt of the distance bracket and the column, and impact energy is generated by plastic deformation of the curling plate. Since this type of tilt steering device absorbs vibration, compared to a structure in which a corrugated or stretch tearing type energy absorber is locked between the tightening bolt and the hooking claw at the bottom of the column with this type of tilt steering device. Of sound due to sound generation and variations in energy absorber manufacturing No variations in characteristics, stable energy absorption characteristics, desired load increasing properties. In addition, compared to the conventional waist swing tilt in which the energy absorbing part is provided on the mounting part of the column bracket with the vehicle body, the moment load at the time of collision does not act, so the maximum peak load can be reduced, and operation during accidental collision is possible. It can reduce the load and injury to persons. Since the steering shaft and the column each have an expandable structure, the impact energy can be absorbed even by the frictional force at the expandable part, and the driving operability can be improved together with the tilt structure. The structure of the entire steering device for absorbing shock is made compact, and many effects are brought about, such as being lightweight and inexpensive to manufacture.

[Brief description of drawings]

1 is a perspective view of a curling plate according to an embodiment of the present invention, FIG. 2 (a) is a partial side view of the first embodiment of the present invention, and FIG. 2 (b) is a steering wheel of the present invention. FIG. 3 is a schematic side sectional view of the lower end of the column, FIG. 3 is a side view showing the state after plastic deformation of the curling plate in the embodiment shown in FIG. 2 (a), and FIG. 4 is IV- of FIG. Fig. 5 is a cross-sectional view taken along line IV, Fig. 5 is a partial side view of the second embodiment of the present invention, Fig. 6 is a side view of a conventional tilt steering device having an impact energy absorbing portion, and Fig. 7 is a side view. Is VII-VI in Fig. 6
FIG. 8 is an enlarged cross-sectional view taken along the line I, and FIG. 8 is a side cross-sectional view of a main part of a steering device having a conventional corrugated energy absorber.
FIG. 9 is a side sectional view showing the state of the steering device of FIG. 8 after plastic deformation. 2a ... upper shaft, 2b ... lower shaft, 2c ...
… Spline groove, 6 …… Steering column, 10 …… Body part, 21 …… Column bracket, 22,33,35 …… Distance bracket, 23 …… Tightening bolt, 30 …… Curling plate, 30c …… Plastic deformation Part, 32 ...... U-shaped bent part, 34 ...... Curling plate bent part regulation guide member, 36 ...... Guide part, 40 ...... Lower bracket, 41 ......
Spherical bush.

Claims (1)

[Scope of utility model registration request] 1. A steering column rotatably supporting a steering shaft, a distance bracket fixed to the column, and a column bracket for fixing the column to a vehicle body via the distance bracket,
In a steering device having an engaging structure in which the steering shaft is capable of expanding and contracting in the axial direction and transmitting rotation, and a front portion of the steering column is supported so as to be tiltable with respect to a vehicle body, a front end portion is close to a front edge of the column bracket. And is fixed to the column, the upper side portion from the front end portion to the U-shaped bent portion at a midway position is in contact with the lower portion of the column and extends forward, and the width gradually increases from the U-shaped bent portion to the front end portion. And a curling plate connected to a tightening bolt inserted into the distance bracket from the column bracket through a long hole at the rear end of the lower side portion,
And a curling plate bent portion restricting guide member that is fixed to the column side to accommodate the curling plate and restrain the lower side of the U-shaped bent portion, and the tightening bolt insertion hole formed in the distance bracket is A laterally elongated notched groove that is open to the rear and has a length exceeding at least the expansion / contraction stroke of the steering shaft and the steering column, and the long hole at the rear end of the curling plate corresponds to the expansion / contraction stroke of the steering column. The shock absorbing steering wheel is formed to have a length, and the curling plate absorbs impact energy by plastically deforming and moving while the U-shaped bent portion is restrained by the column lower side portion and the guide member at the time of impact. apparatus.