JP2002293251A - Support mechanism for steering device - Google Patents

Abstract

(57) [Problem] To provide a small supporting mechanism with a simple configuration, in which the impact force on the steering wheel of the driver is different depending on whether or not the driver wears a seat belt. A steering mechanism (20) for supporting a steering column (11), which is fixed to the steering column (11), passes through a support bracket (21), and a long hole (21b) extending in the front-rear direction provided in the support bracket (21), and is attached to a vehicle body. Support pin 22 for supporting the vehicle body 11 on the vehicle body, and the support pin 22
Plate (energy absorbing member) 23 which can be deformed when the vehicle is relatively moved, a support pin 22 which operates based on both a driver's seat belt wearing signal and a vehicle frontal collision signal.
And a pneumatic cylinder 24 for deforming the bending plate 23 by a predetermined amount through the, and pulling the steering column 11 forward.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support mechanism for a steering device for an automobile.

[0002]

2. Description of the Related Art In a steering apparatus for a vehicle, an airbag is provided on a steering wheel, and a means for absorbing a driver's impact force on the steering wheel by the operation of the airbag at the time of a frontal collision of a vehicle is employed. Although many are equipped with an energy absorbing mechanism on the steering column to absorb the impact force transmitted to the steering wheel,
Some airbags use both an airbag and an energy absorbing mechanism. A steering device using both an airbag and an energy absorbing mechanism takes into account that the impact force on a driver at the time of a frontal collision of a vehicle greatly differs depending on whether or not a seat belt is worn.

The steering device disclosed in Japanese Patent Application Laid-Open No. 4-113954 discloses a method of absorbing an impact force on a driver by operating an air bag equipped on a steering wheel, depending on whether or not the driver wears a seat belt. Instead, it is intended to further reduce the impact force on the driver in the event of a collision by retracting the steering column toward the front of the vehicle.

[0004] In such a steering device, in which the impact on the driver is reduced by moving the steering column forward at the time of a frontal collision of the vehicle, the distance between the steering wheel and the driver's chest is increased. It is important to secure an appropriate value regardless of the driver's physique.

[0005] In the steering device, ideally, when the driver wears the seat belt, there is an appropriate gap between the driver and the steering wheel, and the load entering the chest by the restraining force of the seat belt can be adjusted. If possible, the chest injury value can be kept low. However, adjusting the distance between the driver's chest and the steering wheel
There is a limit from the driving posture of the driver. Further, when the driver does not wear the seat belt, it is necessary to increase the energy absorption load sufficiently to prevent the steering device from bottoming out.

For this reason, the steering apparatus disclosed in the above-mentioned publication has a structure including an airbag and a retracting mechanism for retracting the steering column forward. Calculate the time t1 (time elapsed from the collision), deploy the airbag to time after the collision,
At time t1 thereafter, the ignition circuit operates, the loader operates to pull the wire, and the rear half of the steering column is drawn into the engine room. It is unknown whether or not the steering device is equipped with an energy absorbing mechanism in the steering column.

[0007]

As described above, in the steering apparatus, at the time of a frontal collision of the vehicle, by pulling the steering column forward by a predetermined length, the distance between the steering wheel and the driver's chest can be properly adjusted. However, in order to provide such a function, parts such as a gunpowder live loader, a pulley, and a plurality of wires are to be mounted between the lower side and the upper side of the steering device. The steering device becomes complicated and large.

Accordingly, an object of the present invention is to provide a support mechanism for a steering device having a function of reducing the impact force applied to a driver's steering wheel depending on whether or not the driver wears a seat belt. It is to provide a small and simple configuration.

[0009]

SUMMARY OF THE INVENTION A support mechanism for a steering device according to the present invention (the invention according to claim 1) is for supporting a steering column for rotatably supporting a steering shaft in a circumferential direction on a part of a vehicle body. The support mechanism is attached to a part of the vehicle body through a support member fixed to the steering column and a long hole extending in the front-rear direction provided in the support member. A support pin for supporting the steering column to the vehicle body via a member, an energy absorbing member provided on the support member and deformable by the support pin when the support pin relatively moves through the long hole, and a driver's seat It operates based on both the belt wearing signal and the frontal collision signal of the vehicle, and moves the support member and the support pin relatively to each other through the support pin. And it is characterized in that the energy absorbing member includes an actuation means for a predetermined amount deformed.

In the support mechanism for a steering device according to the present invention, the operating means includes a pneumatic cylinder, and a piston rod of the pneumatic cylinder extends in parallel to a length direction of the elongated hole of the support member. (The invention according to claim 2). Further, the pneumatic cylinder is configured by assembling the piston rod to an inflator, and the inflator is operated based on an airbag operation signal when a driver wears a seat belt. Such invention) can be performed.

[0011]

In the steering device supported by the support mechanism according to the present invention, at the time of a frontal collision of the vehicle, the driver moves forward and interferes with the steering wheel to move the steering column forward. Sometimes. In this case, the support pin that supports the steering column relatively moves rearward in the elongated hole of the support member with a force corresponding to the impact force. During the relative movement of the support pins, the support pins deform the energy absorbing member to absorb the impact energy, and reduce the impact force of the driver on the steering wheel.

In this case, when the driver does not wear the seatbelt (when the driver does not wear the seatbelt), the operating means for relatively moving the support member and the support pin to deform the energy absorbing member does not operate. Instead, the steering wheel is located at a preset position. For this reason, the steering column secures the set sufficient energy absorption stroke, and can sufficiently secure the collision safety of the driver.

When the driver wears the seat belt (when the driver wears the seat belt), the operating means operates based on the driver's seat belt wearing signal and the frontal collision signal of the vehicle. The means relatively moves the support member and the support pin to deform the energy absorbing member by a predetermined amount via the support pin. Further, when the operating means is operated, the support member moves forward with the support pin as a base point, and moves the steering column integrated with the support member forward. This allows
The steering wheel is located in front of the steering wheel at a predetermined distance from the set position, and the distance between the steering wheel and the driver's chest is determined when the driver does not wear the seat belt. An appropriate interval that is sufficiently wider than the interval is obtained. For this reason, the steering column secures a set small energy absorption stroke, and the energy absorption amount by the energy absorbing member is lower than when the driver does not wear the seat belt. Function effectively, and the collision safety of the driver can be sufficiently ensured.

As described above, the support mechanism of the steering device according to the present invention has a function of varying the collision energy absorbing ability of the energy absorbing member provided in the support mechanism depending on whether or not the driver wears the seat belt. Thus, a support mechanism essential for supporting the steering device on a part of the vehicle body is effectively used. For this reason, the support mechanism has a relatively simple structure and low cost, does not require a complicated structure of the steering device, and can suppress a significant increase in cost.

In the support mechanism according to the present invention, it is preferable that a pneumatic cylinder is provided as the operating means. In this case, the piston rod extends in parallel with the length direction of the long hole of the support member. If it is configured to be connected to the support pin, the piston rod operates without causing twisting or stiffness, deforms the energy absorbing member, and accurately moves the steering column forward by the set length. be able to.

Further, if a structure having a pneumatic cylinder is adopted as the operating means, the support mechanism can be configured with a simple structure, and the operating function of the operating means, that is, the operating stroke of the piston rod in the pneumatic cylinder can be reduced. By appropriately changing to a different one, the retraction stroke of the steering column can be tuned freely according to the characteristics of small to large vehicles.

In the case where the pneumatic cylinder is constituted by assembling a piston rod to an inflator, and the inflator is operated based on an airbag operation signal when a driver wears a seat belt, the air pressure is reduced. In a steering device equipped with a bag, the operation signal of the airbag can be used as the operation signal of the operating means, and synchronous operation between the operating means and the airbag can be easily ensured.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIGS. 1 and 2 show a steering device employing a support mechanism according to the present invention. The steering device includes a steering column 11 and a steering shaft 12 inserted through the steering column 11, and the steering shaft 12 is supported in the steering column 11 so as to be rotatable in a circumferential direction.

In the steering device, the rear of the steering column 11 is attached to the upper support bracket 1.
The front of the steering column 11 is supported by a part of the vehicle body (not shown) via a support mechanism 20. In this steering device, when assembled to a vehicle, a front end of the steering shaft 12 is connected to a steering link mechanism (not shown), and a steering wheel (not shown) is assembled to a rear end of the steering shaft 12. Attached.

The upper support bracket 13 is
A bracket that is attached to a part of the vehicle body and supports the steering column 11 so that the steering column 11 can be broken forward. When a predetermined load acts on the steering column 11 toward the front, the steering column 11 is detached and moved forward. It is designed to be movable. Further, the upper support bracket 13 is provided with a lock mechanism of a tilt mechanism, and reference numeral 14 denotes an operation lever for operating the lock mechanism to perform a lock operation and an unlock operation.

As shown in FIGS. 3 to 6, the support mechanism 20 includes a support bracket 21 as a support member, a support pin 22, and a bent plate 2 as an energy absorbing member.
3. It is composed of a pneumatic cylinder 24 as an operating means, and a holder 25 for holding the pneumatic cylinder 24.

The support bracket 21 has a gate-like shape and is horizontally long when viewed from the front-rear direction.
A long hole 21b extending rearward from the central portion is formed in 1a so as to face each other. A projection 21b1 is formed at the lower edge of the base end side of the elongated hole 21b. The support bracket 21 is fixed to the upper part of the outer periphery of the steering column 11 at the lower ends of the left and right side walls 21a.

The support pin 22 is a cylindrical body which is attached to a bracket (not shown) provided on a part of the vehicle body by using bolts 30 while penetrating both long holes 21b of the support bracket 21, and is attached to the bracket. In this state, the front end of the steering column 11 is supported by a part of the vehicle body via a support bracket 21 so as to be rotatable in the vertical direction. As shown in FIG. 5, the support pin 22 is located in a state penetrating at the base ends of both long holes 21b, and moves over the protrusion 21b1 by relative movement (relative movement) with the support bracket 21. Move backward.

The bent plate 23 is formed by bending a plate having a predetermined width by approximately 360 degrees, and opposes an upper wall portion 23a and a lower wall portion 23b while maintaining a predetermined interval. Arc-shaped wall portion 23 connecting 23b
c, and an upright wall portion 23d that rises perpendicularly from the tip of the lower wall portion 23b. Standing wall 23
"d" has a rectangular opening 23d1 that opens upward in the front. A pushing rod 24c of a pneumatic cylinder 24 described later is inserted into the opening 23d1.

The bent plate 23 is welded to the support bracket 21 in a state where the bent plate 23 is positioned by a plurality of pins 21c planted so as to surround the outer periphery of the base end of the long hole 21b in the side wall 21a of the support bracket 21. Is fixed, surrounds the support pin 22 in the support bracket 21, and positions the upright wall portion 23d on the front side of the support pin 22;
In addition, the arc-shaped wall portion 23c passes through the elongated hole 21b behind the support pin 22.

The gas pressure cylinder 24 is provided with a piston 24b provided on an inflator generally employed as a gas generator.
And a pushing rod 24c, a cylinder 24a, a piston 24b slidably fitted in the cylinder 24a, and a cylinder 24a.
And a pushing rod 24c which is slidably inserted into the inside and abuts on the piston 24b.

The cylinder 24a is filled with an ignition device and explosive (not shown), and a seat belt wearing signal (an electric control device not shown when the driver wears the seat belt) is input to the tip of the cylinder 24a. And a harness 24d for inputting an ignition signal from the electric control device based on an airbag operation signal (a signal input by the electric control device for operating the airbag at the time of a frontal collision of the vehicle). . The piston 24b and the pushing rod 24c form a piston rod integrally and function as a piston rod. The pneumatic cylinder 24 is attached to the front side of the center of the support bracket 21 via a holder 25.

The holder 25 has a U-shaped cross section that opens upward, and has a pneumatic cylinder 24 disposed therein.
Into the engaging hole 25a provided on the bottom thereof, and the engaging protrusion 24a provided on the bottom of the cylinder 24a of the pneumatic cylinder 24.
The pneumatic cylinder 24 is held by hooking 1. The holder 25 is attached to each side wall 21a of the support bracket 21 with bolts 26 penetrating through each side wall 21a in a state where the holder 25 is inserted into both side walls 21a.

When the holder 25 is mounted, the pneumatic cylinder 24 is mounted on the upper wall 21 of the support bracket 21.
c is pressed against the bottom wall 25b of the holder 25 by a claw 21d provided on the holder 25c, and is held down from both sides by the tip of each bolt 26 (see FIG. 4). With this mounting structure, the pneumatic cylinder 24 is firmly mounted on the support bracket 21 via the holder 25, and accurate operability during explosive ignition explosion is ensured.

When an ignition signal is input to the harness 24d from an electric control device (not shown), the gas pressure cylinder 24
The explosive charged in the cylinder 24a is ignited to operate. In the pneumatic cylinder 24, the piston 24b slides rearward instantaneously with respect to the cylinder 24a due to the explosion of the explosive, causing the push rod 24c to immediately protrude rearward.

Since the push rod 24c is in contact with the support pin 22 and the support pin 22 is immovably mounted on the vehicle body, the support bracket 21 moves forward with respect to the support pin 22. During this relative movement,
The support pin 22 is provided in the
Then, it moves over the protrusion 21b1 and moves backward in the elongated hole 21b. In addition, when the support pin 22 is relatively moved rearward, as shown in FIG. 6, the support pin 22 deforms the bending plate 23 by a predetermined amount.

The support mechanism 20 constructed as described above is similar to that shown in FIG.
When the driver moves forward and interferes with the steering wheel via the airbag at the time of a frontal collision of the vehicle, the steering column 1
Move 1 forward.

When the driver collides with the steering wheel, the support pins 2 for supporting the steering column 11
Reference numeral 2 relatively moves the elongated hole 21b of the support bracket 21 rearward with a force corresponding to the impact force. When the support pins 22 move relative to each other, the support pins 22 deform the bent plate 23, which is an energy absorbing member, to absorb impact energy and reduce the impact force of the driver on the steering wheel.

In the support mechanism 20, when the driver does not fasten the seat belt, a seat belt wearing signal is not input to the electric control device (not shown). Although the signal is input, the ignition signal is not input to the harness 24d of the pneumatic cylinder 24, and the pneumatic cylinder 24 does not operate. For this reason, the pneumatic cylinder 24 does not deform the bending plate 23, and the steering wheel is located at a preset position provided in advance. Therefore, the steering column 11 secures the set sufficient energy absorption stroke, and can sufficiently secure the collision safety of the driver.

On the other hand, when the driver wears the seat belt,
Since a seatbelt wearing signal is input to an electric control device (not shown), when an airbag operation signal is input to the electric control device during a frontal collision of the vehicle, an ignition signal is input to the harness 24d of the pneumatic cylinder 24. Upon being input, in the gas pressure cylinder 24, the explosive charged in the cylinder 24a ignites and explodes and operates instantaneously, as shown in FIG.
The pushing plate 24c is instantaneously protruded from the cylinder 24a to deform the bent plate 23 by a predetermined amount. For this reason, the support bracket 21 relatively moves forward with the support pin 22 as a base point, and instantaneously moves the steering column 11 integrated with the support bracket 21 forward by a predetermined length.

As a result, the steering wheel is located ahead of the initial disposition position by a predetermined distance, and the distance between the steering wheel and the driver's chest is set so that the driver does not wear the seat belt. An appropriate interval that is sufficiently wider than the time interval is obtained. For this reason, the steering column 11 is set to a set small energy absorption stroke, and the amount of energy absorbed by the bending plate 23 is lower than when the driver does not wear the seat belt, but at this time, the seat belt is effectively used. By functioning, the collision safety of the driver can be sufficiently ensured.

As described above, the support mechanism 20 has a function of varying the absorbing energy of the collision energy by the bending plate 23 provided in the support mechanism 20 depending on whether or not the driver wears the seat belt. Of the vehicle body is supported by a part of the vehicle body. For this reason, the support mechanism 20 has a relatively simple structure, is small in size and low in cost, does not require a complicated structure of the steering device, and can suppress a significant increase in cost. .

Further, the support mechanism 20 employs a structure including a pneumatic cylinder 24 as an operating means for pulling the steering column 11 forward, and the pushing rod 24c is connected to the elongated hole 21 of the support bracket 21.
It extends in parallel to the length direction of b and is connected to the support pin 22. For this reason, the pushing rod 24
c operates without causing twisting or stiffness to deform the bending plate 23, and the steering column 11 can be accurately moved forward by the set length.

As an operating means, the pneumatic cylinder 2
4, the support mechanism 20 is used.
Can be configured to have a simple structure, and by appropriately changing the operating stroke of the pushing rod 24c in the pneumatic cylinder 24 (pneumatic cylinder having a different axial length), the steering column 11 The retraction stroke can be tuned freely according to the characteristics of each of the small to large vehicles.

The gas pressure cylinder 24 is constructed by assembling a piston 24b and a pushing rod 24c to an inflator generally used as a gas generator, and can be obtained at a low cost, and can be operated at a low cost. Since the airbag operation signal, which is the operation signal of the airbag mounted on the steering device, is used, the synchronization between the operation of the pneumatic cylinder 24 and the operation of the airbag is easily and accurately secured. be able to.

The support mechanism 20 supports the steering device in an initial normal state when an airbag operation signal at the time of a frontal collision of the vehicle is not provided, so that the steering device can be used in a normal state. It can function properly as a steering device.

In the above embodiment, a seat belt wearing signal (a signal inputted by an electric control device (not shown) when the driver wears the seat belt) and an airbag operating signal (for operating the airbag at the time of a frontal collision of the vehicle). Although the ignition signal is input from the electric control device to the harness 24d of the pneumatic cylinder 24 based on the signal input by the electric control device, the seat belt wearing signal (not shown when the driver wears the seat belt). The electric control unit sends a signal to the pneumatic cylinder 24 based on a signal inputted by the electric control unit) and a vehicle front collision detection signal (a signal inputted to the electric control unit by a sensor for detecting a vehicle frontal collision).
It is also possible to carry out such a configuration that an ignition signal is inputted to the harness 24d of the above.

[Brief description of the drawings]

FIG. 1 is a partially omitted plan view of a steering device supported by a support mechanism according to an example of the present invention.

FIG. 2 is a partially omitted side view of the steering device.

FIG. 3 is a plan view of a support mechanism that supports the steering device.

FIG. 4 is a front view of the support mechanism.

FIG. 5 is a vertical sectional side view of the support mechanism when the inflator is not operated.

FIG. 6 is a vertical sectional side view of the support mechanism when the inflator is operating.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 ... Steering column, 12 ... Steering shaft, 13 ... Upper support bracket, 14 ... Operation lever, 20 ... Support mechanism, 21 ... Support bracket, 21a ...
Side wall portion, 21b ... long hole, 21b1 ... projection portion, 21c ... upper wall portion, 21d ... claw portion, 22 ... support pin, 23 ... bent plate, 23a ... upper side wall portion, 23b ... lower side wall portion, 23c ...
Arc-shaped wall portion, 23d: standing wall portion, 23d1: opening portion, 2
4 ... Pneumatic cylinder, 24a ... Cylinder, 24a1 ... Hook projection, 24b ... Piston, 24c ... Pushing rod, 24d ... Harness, 25 ... Holder, 25a ... Hook hole, 25b ... Bottom wall, 26 ... Bolt.

Claims (3)

[Claims] 1. A support mechanism of a steering device for supporting a steering column rotatably supporting a steering shaft in a circumferential direction on a part of a vehicle body, the support mechanism comprising: a support member fixed to the steering column; ,
A support pin that is attached to a part of the vehicle body through a long hole extending in the front-rear direction provided on the support member and supports the steering column on the vehicle body via the support member; and the support pin provided on the support member. An energy absorbing member deformable by the support pin when the slot relatively moves,
Actuating means that operates based on both a driver's seat belt wearing signal and a vehicle frontal collision signal to relatively move the support member and the support pin to deform the energy absorbing member by a predetermined amount via the support pin. A steering device comprising: 2. The support mechanism according to claim 1, wherein said operating means includes a pneumatic cylinder, and a piston rod of said pneumatic cylinder extends in a length direction of said elongated hole of said support member. A support mechanism for a steering device, wherein the support mechanism extends in parallel and is connected to the support pin. 3. A steering mechanism according to claim 2, wherein said pneumatic cylinder is constructed by assembling said piston rod to an inflator, and outputs a signal for airbag operation when a driver wears a seat belt. A support mechanism for a steering device, wherein the inflator operates based on the inflator.