JPS6339473B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shock absorbing steering device equipped with an energy absorbing device to ensure the safety of a driver when a vehicle collides. The steering shaft, which is connected to the steering gear through the This relates to a shock-absorbing steering device that uses a plate material with bent curved parts as its main body and absorbs energy in the event of a collision through plastic deformation in which the position of the bent parts is sequentially shifted as the steering column moves forward and downward.

Conventionally, this type of energy absorption device has a structure in which the steering shaft is divided into upper and lower parts and fitted together so that the axial length can be reduced, and a longitudinal groove in the axial direction is installed in the lower shaft fitted inside. A plurality of strips are formed, and an energy absorbing plate with a bent portion is housed in the longitudinal groove, one end of which is fixed to the longitudinal groove end, and the other end is fixed to a cylindrical upper shaft that fits on the outside. is known (for example, Special Publication No. 46-35526). In this structure, plastic deformation of the bent part occurs within the fitting part of the upper and lower two axes, so the plastic deformation progresses while the radius of curvature of the bent part is kept constant, and the plastic deformation resistance is constant with respect to the stroke. Excellent in that respect. However, this steering device has a structure in which the energy absorbing plate has the function of absorbing energy during a collision and transmitting torque from the upper shaft to the lower shaft when the steering wheel is rotated. , it is necessary to use a strong energy absorbing plate, and if the strength of the energy absorbing plate is high, the energy absorption load will increase, so the radius of curvature of the bent part must be increased to reduce the energy absorption load. As a result, the diameter of the steering column increases, resulting in a drawback that the weight of the vehicle cannot be reduced. In a primary collision, when the front of the car is crushed and the steering gear is displaced backwards, the steering shaft deforms as if bent from the central fitting part, which prevents the vertical shaft from smoothly contracting, so stable energy can be generated. Another problem is that it tends to be difficult to absorb.

In addition to the above-mentioned device, there is also known a shock-absorbing steering device in which one end of an energy-absorbing plate with a bent portion is fixed to a vehicle body strength member and the other end is fixed to a steering column (for example, −
156230), but since the lower surface of the bending part of this device is not constrained, the radius of curvature of the bending part is not constant, and the plastic deformation resistance is not constant with respect to the movement stroke of the steering column, making it difficult to operate. The disadvantage is that it can easily give a big shock to people.

An object of the present invention is to provide a shock absorbing steering device that has stable energy absorption performance, is lightweight, and is inexpensive, regardless of the structure of the steering column, steering shaft, etc., and without any special restrictions on installation. do.

To achieve this object, the present invention provides a steering column that rotatably supports a steering shaft, the upper end of which is fixed with a steering handle, and the lower end of which is connected to a universal joint of a shaft that transmits torque to a steering gear; A column bracket that is fixed to a steering column and has a mounting portion having a notch that opens toward the steering handle; a fixing bolt that is inserted into the notch of the column bracket and fixes the column bracket to the vehicle body; and the steering column. and an energy absorbing member disposed between the vehicle body portion and the opposing body portions of the column bracket, the energy absorbing member being in contact with each of the opposing body portions and aligned with the axis of the steering shaft. It has a straight part extending in the direction and a curved part curved in a semicircular arc shape toward the center from the straight part, and the ends of both curved parts are joined to each other at the center to form a substantially W-shape, A central joint part of the energy absorbing member is fixed to either the steering column or the vehicle body side member, each of the ends of the straight part is engaged with the steering column or the other vehicle body side member,
The structure is such that relative movement in the axial direction is impossible.

To explain this with respect to the illustrated embodiment, in FIG. 1, a steering shaft 1 has a steering handle 4 fixed to its upper end, and is rotatably supported by a steering column 3 via a lower bearing 6 and an upper bearing (not shown). The lower end has an upper universal joint 10
The torque of the steering shaft 1 is connected to the steering gear 12 via the lower universal joint 11, and the torque of the steering shaft 1 is transmitted to the steering gear 12 through the universal joints 10 and 11.
is transmitted to. The steering column 3, which is a tubular member, has a column bracket 2 fixed to the steering column 3 at the upper part, and a lower bracket 8 having a column support member 7 that slidably supports the steering column 3 at the lower part.
They are respectively attached to the vehicle body part 9. Although the steering column 3 is only allowed to move forward and downward as in the conventional case, the tube portion of the steering column 3 is not particularly provided with an energy absorbing device. The steering shaft 1 is shown as a single shaft. This is due to the presence of the intermediate shaft provided with two joints 10 and 11, which allows it to be displaced to the position shown by the chain line in the event of a collision, so that the steering shaft 1 is not affected by the thrust upward. Therefore, when the steering shaft 1 is directly connected to the steering gear 12, that is, when the steering shaft 1 is connected via one universal joint, the influence of uplift should be taken into consideration.
Generally, the steering shaft 1 is divided into two shafts, an upper shaft and an upper shaft, as in a known structure, and one shaft is inserted into the inside of the other shaft so that it can be expanded and contracted to enable torque transmission.

As shown in FIG. 2, the column bracket 2 includes a body portion 21 having a U-shaped cross section that is fixed to the steering wheel 3 by means such as welding, and a mounting portion that protrudes outward in a right angle direction from the U-shaped end of the body portion 21. Part 22, 22
A notch 24 (see FIG. 5) is formed in the mounting portion 22 and opens toward the steering handle 4 side. A locking metal fitting 5 having a U-shaped cross section is inserted into the notch 24 of the mounting portion 22 from the opening side of the notch. A hole through which a fixing bolt passes is formed in the opposing flat portion of the locking metal fitting 5. The fixing bolt 13 is inserted into the notch 24 of the mounting portion 22, and the column bracket 2 is fixed to the vehicle body portion 9 with the mounting portion 22 sandwiched between the locking metal fittings 5, thereby fixing the steering column 3. .

The locking fitting 5 is a plate bent into a U-shape, the inner surface of which is coated with a film made of a synthetic resin having a low coefficient of friction, and bolt holes are provided, as described in Japanese Utility Model Application Publication No. 52-141737. However, in 1972-
Two washers coated with a synthetic resin film may be used as described in Publication No. 83132, and
It may also be a metal fitting commonly called a capsule as described in Japanese Patent Publication No. 45-27248 which is widely used.

Among the embodiments of the present invention, except for the fourth embodiment described later, the column bracket 2 is the fixed bracket 1.
It is attached to the vehicle body part 9 via 4, 15, and 16. One side of the flat part of the fixed brackets 14, 15, 16 is in contact with the vehicle body part, and the other side is in contact with the locking metal fitting 5 which holds the mounting part 22 of the column bracket, so that the fixed brackets 14, 15, 16 and the column bracket are in contact with each other. One plate part of the locking fitting 5 is always interposed between the mounting part 22 of the locking member 5, but in the perspective views shown in FIG. Illustrations of the metal fittings 5 and the steering shaft 1 are omitted.

The first embodiment shown in FIGS.
A W-shape is formed by placing two energy absorbing plates 30 that are approximately U-shaped and have one semi-circular curved curved portion 30C shown in the figure back to back. , central part 30
A is fixed to a flat plate-shaped fixing bracket 14 by welding.

The energy absorption plate 30 is the steering column 3
and the vehicle body portion 9 and between the opposing body portions 21 of the column bracket 2, and the outer straight portion of the energy absorbing plate 30 extends in the axial direction of the steering shaft and extends in the direction of the axis of the steering shaft. It is abutted along the

As shown in FIG. 5, both ends 30B of the energy absorbing plate are provided with locking means on both sides of the upper end of the body 21 of the column bracket on the steering handle side, that is, close to the center plate of the energy absorbing plate 30 from the body 21. Each of them can be engaged with a claw 23 serving as a guide member. The claw 23 bends a part of the column bracket 2 as shown in the figure, and attaches the column bracket 2.
When the energy absorbing plate 30 moves toward the steering handle side relative to the column bracket 2 and comes into contact with the pawl 23, the end portion 30B of the energy absorbing plate 30 is prevented from moving further relative to the column bracket 2. It is something to do.

The guide member does not need to be integrally molded with the column bracket 2; for example, a separate plate, block, etc. may be welded to the column bracket. In short, any material that is strong against the force that causes plastic deformation in the energy absorbing plate 30 is sufficient.

The claws 23 engage both ends 3 of the energy absorbing plate 30 when the steering column 3 moves forward and downward.
0B and presses the end 30B. end 30
When B is pressed, the end 30B of the energy absorbing plate
The straight section following 2 attempts to move forward and downward, but at this time, the center section of the energy absorbing plate 30 does not move because it is fixed to the bracket 14 fixed to the vehicle body, and the curved section 30C undergoes plastic deformation and moves to its position. A modification is made in which the numbers are sequentially shifted. That is, the central linear portion becomes longer and the outer linear portions become shorter, elongating and deforming. At this time, the outer straight portions are constrained by the body portion 21 of the column bracket, and the central straight portions of the energy absorbing member 30 are placed back to back and are therefore constrained to each other. Therefore, since the radius of curvature of the curved portion of the energy absorbing plate 30 is kept substantially constant, the energy absorbing power is also kept substantially constant.

Since the pawl 23 as a guide member protrudes close to the central straight portion of the energy absorbing member 30, if the force applied to the steering wheel during a collision is not parallel to the axial direction in the horizontal plane, that is, the car collides. Even in the case of an oblique collision, the curvature of the curved portion of the energy absorbing plate 30 remains substantially constant, and the plastic deformation resistance against the movement stroke of the steering column 3 becomes substantially constant.

FIG. 7 shows a second embodiment of the present invention, in which an energy absorbing plate 31, which is an energy absorbing member, is a single plate having a curved portion 31C bent at two places.
Both ends 31B are connected to the body 21 of the column bracket.
It is fixed to the inside of the side plate by means such as welding.
The central part 31A has a gap 31D and the bent part 31
It is bent in the opposite direction to the bending direction C, and the protruding piece 17, which is an energy absorbing plate locking member fixed at the center of the lower side of the fixed bracket 15, is inserted into this gap 31D, and the protruding piece 17 A jaw 17C that protrudes in the axial direction of the steering column 3 is provided at the lower part of the steering handle side, and this jaw 17C
The lower surface of the tip of the central portion 31A of the energy absorbing plate is engaged thereon.

The column bracket 2 is provided with a claw 25 as in the first embodiment, but since both ends 31B of the energy absorbing plate are fixed to the column bracket 2 and serve as a locking means, the claw 25 is used as a locking means. It doesn't have to be a means to an end. The pawl 25 acts as a guide member that prevents the straight plate on the central portion 31A side from deforming in the lateral direction with respect to the steering column 3.

In the event of a vehicle collision, the central portion 31A engages with the protrusion 17 and becomes a fixed point, both ends 31B move together with the column bracket 2, and the position of the bent portion 31C is sequentially shifted toward both ends 31B to absorb energy. The plastic deformation of the plate 31 is performed while the radius of curvature of the bent portion 31C is kept substantially the same.

Although not shown, as a third embodiment which is a combination of the first embodiment and the second embodiment, one bent piece shown in FIG. 3 is attached to both sides of the protrusion 17 shown in FIG. The energy absorbing plates 30 each having a section are fixed by welding or the like to form the central section, and each end of the energy absorbing plate 30 is not fixed to the column bracket but is attached to the first column bracket.
Similar to the first embodiment, the same effect as in the first embodiment can be obtained even if the first embodiment is engaged with a claw.

In the fourth embodiment shown in FIG. 8, instead of the protrusion 17 provided on the fixed bracket 15 shown in FIG.
A locking pin 18 as an energy-absorbing plate locking member protruding from the lower surface of the plate is inserted into a gap 32D in the center of an energy-absorbing plate 32 having a configuration similar to that shown in FIG. 7, and a fixing bracket is not required. This is an example in which this is not the case. The rest of the structure is the same as that of the embodiment shown in FIG. 7, and the operation is also the same.

The fifth embodiment of FIG.
A rectangular recessed guide portion 19 is provided with respect to the mounting surface of the column bracket 2, and the guide portion 19 is disposed within the inner space of the column bracket 2.
The energy absorbing plate 33, which is a single plate having multiple bent portions 33C, is placed inside this guide portion 19, and is applicable when the body of the column bracket 2 is not formed at right angles to the mounting portion. be done. The energy absorbing plate 33 has both ends 33B connected to the guide part 1.
9 on the side opposite to the steering wheel, or fixed by means such as welding, and a bent portion 33C is provided on the steering wheel side. The center part 33A of the energy absorbing plate has a bending part 33C with a gap 33D.
The locking pin 20 protruding from the upper surface of the steering column 3 is engaged with the tip of the center portion 33A of the gap 33D. Two claws 26 are provided near the end of the guide portion 19 of the fixed bracket on the side opposite to the steering wheel so as to sandwich the energy absorbing plate 33 therebetween. During a vehicle collision, as the steering column 3 moves forward and downward, the center part 33 of the energy absorbing plate
A is pulled downward by the locking pin 20, and both ends 33B are fixed, so the bent portion 33C
Plastic deformation is performed so that the position approaches both ends 33B. The energy absorbing plate 33 is prevented from being deformed in the lateral direction with respect to the steering column 3 by the inner surface of the guide portion 19 of the bracket and the pawl 26 which is a guide member, and the radius of curvature of the bent portion 33C is kept almost constant as in the other embodiments. dripping

The shock-absorbing steering device of the present invention configured as described above includes an energy-absorbing member disposed between the steering column and the vehicle body portion and between the opposing body portion of the column bracket, and the energy-absorbing member is The column bracket has a straight portion that abuts each of the opposing body portions and extends in the axial direction of the steering shaft, and a curved portion that curves in a semicircular arc shape toward the center from the straight portion, and ends of both curved portions. are connected to each other at the center to form a substantially W-shape, and the connecting part at the center of the energy absorbing member is fixed to either the steering column or a member on the vehicle body side, and each of the ends of the straight part is Since it is engaged with the steering column or the other member on the vehicle body side and disables relative movement in the axial direction, there is no need to provide an energy absorption device on the steering shaft or steering column, so it does not have an energy absorption function. The basic structure of conventional steering shafts and steering columns can be used without changing, and the energy absorbing device of the present invention does not cause problems such as a decrease in rigidity or an increase in weight of the steering device. Since the energy absorbing member is W-shaped and symmetrical with respect to the horizontal direction, even in the case of a so-called oblique collision, where an impact force is applied at an angle to the axial direction of the steering column in the horizontal direction. It has the effect of stably absorbing energy. In the present invention, the design is not complicated because the energy absorbing member only needs to have the function of absorbing energy. In addition, since the energy absorption device is provided between the steering column and the vehicle body and between the body of the column bracket, there is no need to take special consideration to space, installation is easy, and it is inexpensive and has energy absorption characteristics. It can provide a good shock absorbing steering device.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is a longitudinal cross-sectional view of the shock absorbing steering device showing how it is mounted on a vehicle; FIG. 2 is a cross-sectional view taken along the line - in FIG. 1; and FIG. FIG. 4 is a perspective view showing how the energy absorbing plate is attached, FIG. 5 is a perspective view showing only a part of the column bracket, and FIG. 6 is a perspective view of the first embodiment. A perspective view showing the state of the energy absorbing device according to the example after operation; FIG. 7 is a partially exploded perspective view of the energy absorbing device according to the second embodiment; FIG. 8 is a perspective view showing the energy absorbing device according to the fourth embodiment FIG. 9 is a perspective view showing a part of the energy absorbing device exploded, and FIG. 9 is a perspective view of the energy absorbing device of the fifth embodiment. [Description of symbols of main parts], 1: Steering shaft, 2: Column bracket, 3: Steering column, 4: Steering handle, 5: Locking bracket, 9: Vehicle body part, 10, 11: Universal joint, 1
3: Fixing bolt, 14, 15, 16: Fixing bracket, 17: Projecting piece, 18: Locking pin, 19: Guide section, 20: Locking pin, 21: Body section, 22: Mounting section, 23, 25, 26: Nail, 30, 31, 32,
33: Energy absorption plate.

Claims (1)

[Scope of Claims] 1. A steering column that rotatably supports a steering shaft, the upper end of which is fixed to a steering handle, and the lower end of which is connected to a universal joint of a shaft that transmits torque to a steering gear; and a steering column that is fixed to the steering column. a column bracket formed with a mounting portion having a notch that opens toward the steering handle; a fixing bolt that is inserted into the notch of the column bracket and fixes the column bracket to the vehicle body; and a fixing bolt that is inserted between the steering column and the vehicle body. and an energy absorbing member disposed between the column bracket and the opposing body portions of the column bracket, the energy absorbing member abutting each of the opposing body portions and extending in the axial direction of the steering shaft. It has an extending straight line part and a curved part curved in a semicircular arc shape toward the center from the straight line part, and the ends of both curved parts are connected to each other at the center to form a substantially W-shape, and the energy is The central connecting part of the absorbing member is fixed to either the steering column or the vehicle body side, and each of the ends of the straight part is engaged with the steering column or the other vehicle body side member, and the axially relative A shock absorbing steering device characterized by being immovable. 2. In the shock-absorbing steering device according to claim 1, the locking means has a claw that is close to the central joint of the energy absorbing member, and the locking means has a claw that is close to the central joint of the W-shaped energy absorbing member. Shock-absorbing steering device, which is prevented from lateral displacement.