JP2004345561A - Steering column device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To adjust the interval between a steering wheel and a driver to an interval required for operating an air-bag just before a collision, even when the driver is a woman small stature or the like having a relatively small physique. <P>SOLUTION: A detection sensor S of an obstacle or the like recognizes an obstacle and the other vehicles, and a pre-crash safety computer PCC determines whether or not the collision can be avoided based on the position, speed, course, and the like of an object such as the obstacle. If the the driver is a small woman or the like having a relatively small physique and it is determined that the collision cannot be avoided, the pre-crash safety computer PCC issues a driving signal to a column driving mechanism 47. Thus, for increasing the interval between the steering wheel 11 and the driver, namely before the air bag comes into a full open state, the steering wheel 11 is evacuated (toward the front side of the vehicle) to a position required for operating the air bag. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a steering column device for a vehicle, and more particularly to a technique for improving driver safety when an airbag is deployed.
[0002]
[Prior art]
When a vehicle collides with another vehicle, a building, or the like, the driver may cause a secondary collision with the steering wheel due to inertia. In recent years, in order to prevent a driver from being injured in such a case, an airbag is widely used in addition to an impact-absorbing steering shaft and an impact-absorbing steering column device. In a shock absorbing type steering column device, when a driver makes a secondary collision, the steering column separates together with the steering shaft. Usually, the steering column collapses simultaneously with the steering shaft, and at that time, shock energy is absorbed. As described in JP-B-46-35527, a metal ball is interposed between the outer column and the inner column to form a plastic groove on the inner peripheral surface of the outer column and the outer peripheral surface of the inner column during collapse. The ball type which is used is often used. An airbag is a bag made of nylon cloth or the like, which is stored in a steering pad or the like, and is deployed and inflated using a gas generator (inflator) in the event of a collision. To prevent.
[0003]
By the way, the airbag deploys and inflates in a very short time based on an output signal of an acceleration sensor or the like at the time of a collision, and this causes the following problem. Normally, the capacity (volume when inflated) of the airbag is set on the assumption that a driver of a standard size drives a vehicle in a standard posture. However, when the driver is a small woman with a short arm, the distance between the steering wheel and the driver tends to be smaller than an expected value by pulling the steering column or advancing the seat. . In this state, if the airbag is suddenly deployed due to the collision of the vehicle, the rear surface of the airbag will bang the driver's face and chest, and the spectacle wearer may suffer unexpected damage. Generally, the distance between the steering wheel and the driver's body is desirably 25.4 cm (10 inches) or more, as described in a collision test report of the United States NHTSA (National Highway Traffic Safety Administration). It has been.
[0004]
In view of such circumstances, Patent Literature 1 discloses a column driving mechanism that moves a steering column forward and backward with respect to a driver, a distance measuring sensor that detects an interval between the driver and the steering wheel, and a driving method based on the detection result. An electronic control unit (ECU) that controls a column drive mechanism in order to maintain a distance between a driver and a steering wheel at or above a predetermined value is disclosed.
[0005]
Thus, when the vehicle starts running, the electronic control unit (ECU) repeatedly calculates the distance between the steering wheel and the driver based on the detection signal of the distance measurement sensor.
[0006]
In the case where the driver is a small woman or the like having a relatively small weight, if the interval becomes equal to or less than a predetermined value (for example, 26 cm), the electronic control unit (ECU) determines that the interval between the steering wheel and the driver is small. The steering wheel is advanced until it increases to a predetermined value. As a result, even when the driver's physique is small, an unnecessary impact is not applied to the driver's chest or head when the airbag is deployed.
[0007]
On the other hand, there are cases where the distance between the steering wheel and the driver cannot be increased to a predetermined value even though the column drive mechanism advances the steering wheel.
[0008]
Further, even if the electronic control unit (ECU) drives the column driving mechanism to set the interval to a predetermined value, the driver sometimes operates the column driving mechanism by himself / herself to bring the steering wheel closer.
[0009]
In these cases, the electronic control unit (ECU) outputs a drive current to the warning device, and issues a warning to the driver by voice or lighting of the lamp that "the steering wheel is too close to the driver".
[0010]
Then, when the vehicle collides with an obstacle in such a state, the electronic control unit (ECU) sets the deployment amount of the airbag to a small value and outputs a drive current to the inflator. Thus, even when the distance between the steering wheel and the driver is small, the possibility that an excessive impact is applied to the driver's chest or head when the airbag is deployed is reduced.
[0011]
[Patent Document 1]
JP 2002-255042 A
[0012]
[Problems to be solved by the invention]
However, in the safety system described above, when the driver is a small woman or the like having a relatively small size, the distance required between the steering wheel and the driver in order to steer the steering wheel is determined when the airbag is activated. Sometimes it is smaller than the required interval.
[0013]
Under such conditions, in the above safety system, the electronic control unit (ECU) determines that the distance between the steering wheel and the driver is smaller than a predetermined distance, and turns on the warning light during driving. Or the alarm may continue to sound, which may be rather complicated for the driver despite the safety system.
[0014]
Further, in the case of the above-described conditions, as described above, since the configuration is such that the deployment amount of the airbag is small, it is not always possible to secure the deployment amount necessary for the driver at the time of collision. .
[0015]
The present invention has been made in view of the above circumstances, and even when the driver is a small woman or the like having a relatively small physique, immediately before the collision, the steering wheel and the driver need An object of the present invention is to provide a steering column device for a vehicle including a pre-crash safety system capable of adjusting an interval therebetween to an interval required for operation of an airbag.
[0016]
[Means for Solving the Problems]
In order to achieve the above object, a vehicle steering column device according to claim 1 of the present invention includes a column driving unit that causes a driver to move a steering column forward and backward,
Column control means for controlling the column drive means, so as to maintain the distance between the driver and the steering wheel at a predetermined value or more;
While the vehicle is traveling, obstacles and the like detecting means for detecting obstacles on the course and other vehicles,
Based on the detection result of the obstacle or the like detection means, predicts a collision with an obstacle or another vehicle, and when the collision is predicted, the distance between the driver and the steering wheel is maintained at a predetermined value or more. A pre-crash safety control means for issuing a drive signal to the column control means.
[0017]
As described above, according to the first aspect, the obstacle or the like is recognized by the obstacle or the like detection means, and the position, speed, course, or the like of the object such as the obstacle is recognized by the pre-crash safety control means. It is determined whether a collision is inevitable.
[0018]
On the other hand, when the driver is a small woman or the like having a relatively small physique, the necessary interval between the steering wheel and the driver at the time of steering may be smaller than the interval required between the two at the time of airbag operation.
[0019]
Under these conditions, if it is determined that a collision is inevitable, the steering wheel is moved forward so as to increase the distance between the steering wheel and the driver. That is, before the airbag is fully opened, the steering wheel is retracted (toward the front of the vehicle) to a position necessary for the operation of the airbag.
[0020]
Therefore, even if the driver is a small woman with a relatively small physique, the distance between the steering wheel and the driver should be adjusted to the interval necessary for the operation of the airbag immediately before the collision. Can be.
[0021]
In other words, when the driver is a small woman with a relatively small size, during normal steering, the distance between the steering wheel and the driver can be driven at a relatively small interval, and a warning or warning sound is issued. You will be free from such annoyance. At the same time, even if driving at this small interval, just before the collision, the interval between the steering wheel and the driver can be adjusted to the interval necessary for the operation of the airbag. In addition, from this, even if the electric motor or the gear reducer is used as the column driving means, it is possible to cope with the collision speed.
[0022]
Further, as compared with the case of Patent Document 1, when the distance between the steering wheel and the driver cannot be maintained at a predetermined level, there is no need to provide a warning device or the like that emits a warning or a warning sound, thereby reducing manufacturing costs and driving. Person is released from the trouble such as a warning sound. In addition, when the distance between the steering wheel and the driver cannot be maintained at a predetermined level, it is not necessary to set the airbag deployment amount to be particularly small. Can be secured.
[0023]
Furthermore, a steering column device for a vehicle according to a second aspect of the present invention is characterized in that, in the first aspect, the column driving means is an actuator for adjusting a position of a steering.
[0024]
As described above, a gas generator is an example of an actuator that instantaneously moves the steering column. However, once the actuator is operated, parts need to be replaced, and there is a problem that the service code is high. On the other hand, according to the second aspect, since the actuator is operated by the electric motor or the gear reducer of the actuator, there is no need to replace parts and the service cost can be reduced.
[0025]
Further, the vehicle steering column device according to claim 3 of the present invention is characterized in that, in claim 1, the vehicle further comprises an interval detecting means for detecting an interval between the driver and the steering wheel.
[0026]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment in which the present invention is applied to an electric telescopic steering column device will be described with reference to the drawings.
[0027]
FIG. 1 is a side view showing a passenger compartment of a passenger car according to the embodiment, and reference numeral 1 in the figure denotes a steering device. The steering device 1 includes a steering column device 7 attached to a vehicle body-side member 2 via an upper bracket 4 (release plate 3) and a lower bracket 5, and an upper steering shaft rotatably held by the steering column device 7. 9, a steering wheel 11 mounted on an upper end of the upper steering shaft 9, a lower steering shaft 15 connected to a lower end of the upper steering shaft 9 via a universal joint 13, and the like. In the drawing, a member indicated by reference numeral 17 is a steering pad provided at the center of the steering wheel 11, and accommodates a variable capacity airbag, an inflator 19 for deploying the airbag, and the like.
[0028]
In this steering device, when the driver rotates the steering wheel 11, the rotational force is transmitted to a steering gear (not shown) via the upper steering shaft 9 and the lower steering shaft 15. The steering gear has a built-in rack-and-pinion mechanism for converting a rotational input into a linear motion, and the steering is performed by changing the steering angle of the wheel via a tie rod or the like. Various types of steering gears, such as a ball screw type and a worm roller type, are known in addition to the rack and pinion type.
[0029]
The driver 21 is seated on the driver's seat 25 attached to the floor pan 23 and is restrained by the seat 25 by the seat belt 27. The seat 25 moves back and forth along a seat rail 29 fixed to the floor pan 23, and the angle of the backrest 31 can be adjusted according to the riding posture of the driver.
[0030]
An ECU (Electronic Control Unit) 37 is installed between the dash panel 33 and the instrument panel 35, while the steering pad 17 measures an interval with the driver 21 at a portion that does not interfere with an airbag or the like. An infrared or ultrasonic ranging sensor 39 is built in, and a detection signal of the ranging sensor 39 is transmitted to the ECU 37. The distance measuring sensor 39 may be installed on the instrument panel 35, the front end of the head lining (not shown), or the like.
[0031]
FIG. 2 is a longitudinal sectional view of the steering column device 7, FIG. 3 is a view taken in the direction of the arrow A in FIG. 2, and FIG. 4 is a sectional view taken along the line BB in FIG. As shown in these figures, the steering column device 7 includes an outer column 41 and an inner column 43 both made of steel pipe, an aluminum die-cast column holder 45 in which the outer column 41 is slidably fitted, and an electric motor. A column driving mechanism 47 also serving as a telescopic mechanism and a collision energy absorbing mechanism 49 are main components.
[0032]
As shown in FIG. 2, the upper steering shaft 9 is composed of an outer shaft 51 on the steering wheel side and an inner shaft 53 on the lower steering shaft 15 side, and the outer shaft 51 and the inner shaft 53 It is fitted slidably in the axial direction by splines and the like. In FIG. 2, reference numerals 55 and 57 denote bearings fitted and held in the outer column 41 and the inner column 43, and rotatably hold the upper steering shaft 9.
[0033]
As shown in FIGS. 3 and 4, the upper bracket 4 includes a pair of vehicle body mounting portions 4a, 4a extending obliquely upward from both sides of the column holder 45 and provided substantially horizontally along the vehicle body side. Have.
[0034]
Notch portions 3a, 3a opened toward the vehicle rear side are formed in the pair of vehicle body mounting portions 4a, 4a, respectively. The detachable plate 3 formed by folding a plate-like member into two is attached to the pair of cutout portions 3a, 3a of the pair of vehicle body attachment portions 4a, 4a.
[0035]
The support bolts 61 penetrate through a pair of notches 3a, 3a of the pair of vehicle body mounting portions 4a, 4a, the detachment plate 3, and bent portions 111b, 111b of the ironing wire 111 described later, respectively. Inserted) and fixed to the vehicle body.
[0036]
Thus, when the steering column device 7 moves forward of the vehicle at the time of a secondary collision, the support bolts 61, 61 remain on the vehicle body side, and the upper brackets 4a, 4a, together with the column holder 45 and the like, have the notch 3a. , 3a, it is detached from the support bolts 61, 61 and moves forward of the vehicle.
[0037]
That is, in the case of the present embodiment, the column holder 45 is held by the separation plate 3 via the support bolt 61, and when a predetermined forward load is applied, the column holder 45 is separated from the separation plate 3 (that is, the vehicle body side member 2). Leave ahead.
[0038]
In FIG. 2, reference numeral 63 denotes a pressure pad which is held at two upper positions of the column holder 45 and locks the outer column 41 with a predetermined frictional force. Reference numeral 65 denotes a pressure pad for biasing the pressure pad 63 toward the outer column 41. Is shown. Reference numerals 67 and 69 denote nuts with a hexagonal hole having a detent made of a synthetic resin. The nuts are screwed into the column holder 45 to press and hold the disc spring 65. A locking projection 71 is projected from the right nut 67 in FIG. 2, while a long hole 73 into which the locking projection 71 is fitted is formed in the outer column 41, and the outer column 41 and the column holder 45 are formed. Relative rotation is prevented.
[0039]
The column drive mechanism 47 includes an electric motor 81 which is mounted on the column holder 45 and driven and controlled by the ECU 37, a feed gear 83 and a worm pinion 85 built in the column holder 45, and a feed gear 83 for the column holder 45. It comprises a rotatable bearing 87, a telescopic shaft 89 penetrating the feed gear 83, and the like.
[0040]
The worm pinion 85 is fixed to an output shaft of the electric motor 81, and rotates forward and backward with the rotation of the electric motor 81. The feed gear 83 has an outer circumference formed on a worm wheel 91 screwed into the worm pinion 85, and an inner circumference formed on a female screw 95 screwed into a male screw portion 93 of the telescopic shaft 89.
[0041]
In the drawing, reference numeral 97 denotes a telescopic bracket which is welded to the outer column 41 and connects the telescopic shaft 89 and the outer column 41 via a nut 99. Reference numeral 101 denotes a push screw which is screwed into the column holder 45 and adjusts a backlash or the like between the feed gear 83 and the bearing 87. Reference numeral 103 denotes a lock nut screwed into the push screw 101.
[0042]
The impact energy absorbing mechanism 49 is a known ironing wire type, and is bent 90 ° rearward from the front left and right ends of the column holder 45, and then bent forward in U-shape by the left and right support bolts 61. The ironing wire 111 is an element.
[0043]
That is, the ironing wire 111 has a connecting portion 111 a connected to the front surface of the column holder 45, and a circular shape in which the left and right support bolts 61 are wound after being bent 90 ° rearward from the left and right ends of the connecting portion 111 a. The vehicle includes a pair of bent portions 111b, 111b bent in an arc shape (U shape), and extending portions 111c, 111c extending from the bent portions 111b, 111b to the front of the vehicle.
[0044]
In the collision energy absorbing mechanism 49, when the column holder 45 moves forward at the time of collision, the ironing wire 111 is squeezed in such a manner that the column holder 45 and the ironing wire 111 move together and wrap around the two support bolts 61 to reduce the collision energy. Absorb.
[0045]
Next, in the present embodiment, a pre-crash safety system is provided. The pre-crash safety system includes an obstacle detection sensor S disposed on a front grill of a vehicle and a pre-crash safety computer PCC disposed in an electronic control unit 37 (ECU).
[0046]
The obstacle detection sensor S is, for example, a millimeter wave radar, and transmits and receives millimeter waves to recognize other vehicles and obstacles on the course while the vehicle is running. The millimeter wave radar recognizes vehicles and obstacles on the course, and determines whether or not collision is unavoidable from the position, speed, and course of the target object using the pre-crash safety computer PCC. The pre-crash safety computer PCC transmits the information to the electronic control unit 37 (ECU) by, for example, CAN communication, and causes the column drive mechanism 47 to operate.
[0047]
Millimeter waves are radio waves having a very high frequency band of 30 GHz to 300 GHz and a wavelength in a vacuum of 1 to 10 mm, which is extremely short. Millimeter waves are hardly affected even under conditions such as rain, fog, and snow, and can exhibit excellent performance in object recognition. The pre-crash safety system employs a 76 GHz band radar.
[0048]
If an object exists within the range of the millimeter wave radar, the reflected wave detects the distance, relative speed and direction to the object, and determines whether collision is unavoidable by the pre-crash safety computer PCC based on the data. I do.
[0049]
The direction of the object is detected using the angle of the reflected wave, and the distance to the object is detected using the time from the emission of the radio wave to the return of the reflected wave, Further, the speed of the object is detected by using a change in the frequency of the reflected wave (Doppler effect).
[0050]
In the curve, the radius of the curve is estimated based on the information of the yaw rate sensor and the steering sensor, and the course is corrected.
[0051]
As a non-operational condition, in the pre-crash safety system,
a. When the relative speed is about 30 km / h or less
b. When the vehicle speed is 5 km / h or less
c. When the ignition switch is OFF and when the ignition switch is ACC
d. When the warning lamp is on and blinking
e. When the pre-crash sensor cannot detect the collision object
In addition, those that cannot be detected are those that cannot be detected stably, such as people, bicycles, motorcycles, standing trees, animals, and snow walls.
[0052]
Next, the operation according to the present embodiment will be described.
[0053]
When the vehicle starts running, the ECU 37 repeatedly calculates the distance L between the steering wheel 11 and the driver 21 based on the detection signal of the distance measurement sensor 39. If the driver 21 is a small woman with a relatively small weight and the interval L becomes equal to or less than a predetermined value LD (for example, 26 cm), the ECU 37 supplies a drive current to the electric motor 81 of the column drive mechanism 47. Output, and rotates the feed gear 83 in a predetermined rotation direction via the worm pinion 85. Then, the telescopic shaft 89 screwed to the feed gear 83 moves forward, and the outer column 41 connected to the telescopic shaft 89 also moves forward until the distance L between the steering wheel 11 and the driver 21 reaches a predetermined value LD.
[0054]
Next, in the present embodiment, an obstacle or other vehicle is recognized by the obstacle or the like detection sensor S, and the position, speed, course, or the like of the object or the like is detected by the pre-crash safety computer PCC. It is determined whether a collision is inevitable.
[0055]
On the other hand, when the driver is a small woman or the like with a relatively small physique, the necessary interval between the steering wheel 11 and the driver during steering may be smaller than the interval required between the two during the airbag operation. .
[0056]
Under these conditions, if it is determined that a collision is inevitable, the pre-crash safety computer PCC sends a drive signal to the electronic control unit 37 (ECU) that controls the column drive mechanism 47 (ie, the electric motor 81). Emit. Thus, the steering wheel 11 is moved forward so as to increase the distance between the steering wheel 11 and the driver.
[0057]
That is, before the airbag is fully opened, the steering wheel 11 is retracted (toward the front of the vehicle) to a position necessary for the operation of the airbag.
[0058]
Therefore, even if the driver is a small woman or the like having a relatively small size, immediately before the collision, the distance between the steering wheel 11 and the driver is adjusted to a distance necessary for the operation of the airbag. be able to.
[0059]
In other words, when the driver is a small woman or the like with a relatively small physique, during normal steering, the distance between the steering wheel 11 and the driver can be driven at a relatively small interval. Relieved from the hassle. At the same time, even if the vehicle is driven at this small interval, immediately before the collision, the interval between the steering wheel 11 and the driver can be adjusted to the interval required for the operation of the airbag.
[0060]
Also, from this, even if the electric motor 81 or the gear reducer as the actuator is used as the column driving mechanism 47, it is possible to cope with the collision speed.
[0061]
Furthermore, compared to the case of Patent Document 1, when the distance between the steering wheel 11 and the driver cannot be maintained at a predetermined value, there is no need to provide a warning device or the like that emits a warning or a warning sound, and the manufacturing cost can be reduced. The driver is released from the trouble such as a warning sound. Further, when the distance between the steering wheel 11 and the driver cannot be maintained at a predetermined value, it is not necessary to set the deployment amount of the airbag to be particularly small. Can be secured.
[0062]
Further, as an actuator for instantly moving the steering column, there is a gas generator or the like. However, once the actuator is operated, there is a problem that replacement of parts is required and service cost is high. On the other hand, according to the present embodiment, since the actuator is operated by the electric motor 81 or the gear reducer of the actuator, there is no need to replace parts and the service cost can be reduced.
[0063]
This concludes the description of specific embodiments, but aspects of the present invention are not limited to the above embodiments.
[0064]
For example, in the above embodiment, the present invention is applied to an electric telescopic steering column device, but may be applied to an electric tilt telescopic steering column device or the like.
[0065]
In addition, the specific structure of the column drive mechanism, including the entire configuration of the steering device, can be appropriately changed without departing from the gist of the present invention.
[0066]
Furthermore, the above-described embodiment is a combination of the electric telescopic type and the pre-crash safety system. Adjustment is also possible.
[0067]
Further, the steering column device may be retracted by a predetermined amount when it is determined that a collision is unavoidable without attaching the sensor S.
[0068]
【The invention's effect】
As described above, according to the first aspect, even when the driver is a small woman or the like having a relatively small size, immediately before the collision, the distance between the steering wheel and the driver is reduced by the air. It can be adjusted to the interval required for the operation of the back. That is, when the driver is a small woman or the like having a relatively small physique, during normal steering, the distance between the steering wheel and the driver can be driven at a relatively small interval. You will be free from it. At the same time, even if driving at this small interval, just before the collision, the interval between the steering wheel and the driver can be adjusted to the interval necessary for the operation of the airbag. In addition, from this, even if a motor is used as the column driving means, it is possible to cope with the collision speed.
[0069]
Further, according to the second aspect, since the actuator is operated by the electric motor of the actuator, there is no need to replace parts and the service cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a side view showing the interior of a passenger car according to an embodiment.
FIG. 2 is a longitudinal sectional view of a steering column.
FIG. 3 is a view as viewed in the direction of the arrow A in FIG. 2;
FIG. 4 is a sectional view taken along line BB in FIG. 2;
[Explanation of symbols]
1 ‥‥ Steering device
3 ‥‥ release plate
3a Notch
4 ‥‥ upper bracket
4a ‥‥ body mounting part
7 ‥‥ steering column device
11 ‥‥ steering wheel
19 ‥‥ inflator
21 ‥‥ Driver
37 ‥‥ ECU
39 ‥‥ distance measuring sensor
40 ‥‥ warning device
41 ‥‥ outer column
43 ‥‥ inner column
45 ‥‥ column holder
47 ‥‥ column drive mechanism
49 ° collision energy absorption mechanism
61 ‥‥ support bolt
81 ‥‥ electric motor
83 ‥‥ feed gear
85 ‥‥ warm pinion
89 ‥‥ telescopic shaft
97 ‥‥ Telescopic bracket
111 ‥‥ ironing wire
111a ‥‥ joint
111b bent part
111c extension
S ‥‥ Obstacle detection sensor
PCC @ Pre-Crash Safety Computer

Claims (3)

Column driving means for moving the steering column forward and backward with respect to the driver;
Column control means for controlling the column drive means, so as to maintain the distance between the driver and the steering wheel at a predetermined value or more;
While the vehicle is traveling, obstacles and the like detecting means for detecting obstacles on the course and other vehicles,
Based on the detection result of the obstacle or the like detection means, predicts a collision with an obstacle or another vehicle, and when the collision is predicted, the distance between the driver and the steering wheel is maintained at a predetermined value or more. A vehicle steering column device comprising: a pre-crash safety control means for issuing a drive signal to the column control means. 2. The vehicle steering column apparatus according to claim 1, wherein the column drive unit is a steering position adjustment actuator. The vehicle steering column device according to claim 1 or 2, further comprising an interval detection unit that detects an interval between the driver and the steering wheel.

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