JPH06253946A - Headrest position adjustment device - Google Patents

Abstract

PURPOSE:To achieve higher effect of reducing damages to a neck part by adjusting a head rest body longitudinally and vertically to the optimum position based on the position of the top of a shoulder determined with first and second distance measuring sensors and an ECU as reference. CONSTITUTION:For example, a relative position of the top of a shoulder is determined with an ECU 5 with respect to a head rest body 6 existing at a reference position known based on distances calculated from the results of detection with both the distance measuring sensors 3 and 4 and infrared irradiation angles of both the sensors 3 and 4. Moreover, the distance is calculated to a point Q corresponding to the top of the shoulder from a reference point P at a lower end of the head rest body 6 to obtain a longitudinal direction component Ld and a vertical Le of the distance between the points P and Q. The rotation of a first motor 9 is transmitted to a rack 8 with gears 11 and 13 to move the rack 8 longitudinally and with the gears 12 and 14, the rotation of a second motor 10 is transmitted to a rack at the lower end part of a support bar 7 to move the support bar 7 vertically. Thus, the head rest body can be adjusted to the optimum position thereby achieving a reduction in damages to a neck part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a headrest position adjusting device for adjusting the position of a headrest provided on a seat in order to prevent or reduce injury to the occupant's cervical portion at the time of a rear collision.

[0002]

2. Description of the Related Art Conventionally, the headrest has a structure in which the vertical position can be adjusted according to the seat height of an occupant seated on the seat. Normally, this adjustment is performed manually, but the seated posture of the occupant has changed. It is sometimes extremely difficult to readjust the headrest position each time, especially when the occupant is driving.

Further, when the occupant changes, it is necessary to adjust the position of the headrest according to the occupant's body shape, but when an unspecified number of occupants are seated such as in a taxi or a bus, the headrest position is adjusted. Adjustment is a very tedious task.

Therefore, for example, Japanese Patent Laid-Open No. 60-158808.
As disclosed in Japanese Patent Laid-Open No. 60-259550, Japanese Patent Laid-Open No. 63-79757, and the like, a sensor detects the position of the head relative to the eyes or the crown, and the detected head is detected. It is considered that the vertical position of the headrest is automatically adjusted by an up-and-down mechanism according to the position of No. 1 and the manual adjustment of the position of the headrest is unnecessary.

By the way, the occurrence of cervical injury called whiplash is determined by the magnitude of the deflection angle to the front and back of the head around the base of the cervical portion. When this deflection angle exceeds a certain value, It is said that a partial injury will occur.

[0006]

However, there are individual differences in the distance between the base of the cervical part and the eyes or the crown, and the sitting posture also differs depending on the person, such as the person in the front or the person who sits deeply. In the method of detecting the position of the head as described above and automatically adjusting the vertical position of the headrest according to it,
The position of the adjusted headrest relative to the actual position of the base of the cervical part may be too close to the top and bottom, and further to the front and back, and it may not be adjusted to the optimum position, so it is possible to obtain a sufficient effect of reducing cervical part injury. Can not.

Therefore, the present invention has been made to solve the above problems, and an object thereof is to improve the effect of reducing cervical injury.

[0008]

SUMMARY OF THE INVENTION A headrest position adjusting device according to the present invention is a light emitting element which is provided in a passenger compartment and irradiates light to almost the top of the shoulder of an occupant seated in a seat, and reflected light from the top of the shoulder. A distance measuring sensor including a light receiving element for receiving the light, and a distance between the top of the shoulder and the installation position of the sensor is calculated based on timings of light emission and light reception by the distance measuring sensor to derive the position of the top of the shoulder. A computing means, a supporting means movably provided in the up-and-down and front-back directions and supporting the headrest body, a driving means for moving the supporting means, and a driving means for controlling the driving means to move the headrest body to the top of the shoulder. It is characterized in that it is provided with control means for adjusting the position in the vertical and front-back directions to the optimum position.

[0009]

In the present invention, the position of the top of the shoulder is calculated by the distance measuring sensor and the calculating means, and the headrest body is adjusted to the optimum position in the vertical and front-back directions with reference to the position of the top of the shoulder. Since the top of the shoulder is closer to the base of the groin than the eyes and the crown, it is possible to adjust the headrest body to a position that is more effective in reducing cervical injury than before. Become.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of an embodiment of a headrest position adjusting device of the present invention, FIG. 2 is a partial perspective view of a part, FIG. 3 is a layout explanatory view, and FIG. 4 is a layout and operation explanatory view.
FIG. 5 is a flowchart for explaining the operation.

As shown in FIG. 3, a first distance measuring sensor (hereinafter referred to as a first sensor) 3 is provided on the ceiling of the passenger compartment above the seat back 2 of the driver's seat 1, and as shown in FIG. A second distance measuring sensor (hereinafter referred to as a second sensor) 4 is provided on the left side of the upper end of the seat back 2, and both of these sensors 3 and 4 are red that irradiate a pulsed infrared light to the apex of approximately the shoulder. Each of the external light emitting elements 3a and 4a and each of the infrared light receiving elements 3b and 4b that receive the reflected light from the top of the shoulder are included.

At this time, the first sensor 3 is the seat back 2
Since the occupant is seated in the driver's seat 1, the first sensor 3 can irradiate infrared light to the top of the shoulder to receive reflected light, and pulsed infrared light can be received. It is emitted from the first sensor 3.

Then, as shown in FIG. 1, the ECU 5 as a calculation means calculates the time from when the first sensor 3 irradiates the pulsed infrared light to when the infrared light is reflected by the first sensor 3.
The distance La from the installation position of the first sensor 3 to the top of the shoulder is calculated, the pulsed infrared light is similarly emitted from the second sensor 4, and the second sensor 4 is emitted from the emission of the pulsed infrared light. Based on the time until the reflected light is received by the ECU 5, the ECU 5 causes the distance L from the installation position of the second sensor 4 to the top of the shoulder.
b is calculated.

By the way, the second sensor 4 has a structure in which the depression angle of the irradiation light can be varied by mechanically changing the angle of the optical axis of the optical system. When the depression angle is gradually changed and the depression angle of the irradiation light changes from the depression angle that does not hit the shoulder to the depression angle that starts to hit, the distance calculated by the ECU 5 changes from a large value to an extremely small value. By deriving the irradiation point when the calculated distance changes in such an extremely small manner, the irradiation point by the second sensor 4 is substantially equal to the apex of the shoulder and substantially coincides with the irradiation point by the first sensor 3,
Therefore, for example, the top of the shoulder at an intermediate position between the irradiation points of both sensors 3 and 4 may be set.

Then, the ECU 5 controls both sensors 3, 4
Based on the distances La and Lb calculated from the detection results of 1 and the irradiation angles of both sensors 3 and 4, for example, the relative position of the top of the shoulder to the headrest main body 6 at a known reference position is derived, and further shown in FIG. Thus, the distance Lc from the reference point P at the lower end of the headrest body 6 to the point Q corresponding to the top of the shoulder is calculated, and the front-back direction component Ld of the distance between the points P and Q in the right side view shown in FIG. Vertical component L
e is calculated. Here, since the state of the headrest body 6 at the time of assembly is known in advance, the above-mentioned reference position of the headrest body 6 is known data, and the ECU 5 is previously stored.
Can be entered in.

Next, the structure of the moving mechanism of the headrest main body 6 will be described. As shown in FIG. 4, the support rod 7 fixed to the lower portion of the headrest main body 6 is seatback 2.
A rack 8 which is inserted into the seat back 2 and is provided movably in the front and rear direction in the upper part of the seat back 2 and constitutes a support means together with the support rod 7 holds substantially the central portion of the support rod 7 movably in the vertical direction. The support rod 7 and the headrest body 6 move in the front-rear direction in conjunction with the rack 8 as the support 8 moves in the front-rear direction.

Further, the lower end of the support rod 7 is formed in a rack shape, and has a small diameter on the rotary shafts of the first and second motors 9 and 10 as drive means controlled by the ECU 5 which functions as control means. The gears 11 and 12 of the rack 8 and the support rod 7 are attached to the gears 11 and 12, respectively.
Gears 13 and 14 with large diameters that mesh with the rack parts of
Is provided, the rotation of the first motor 9 is transmitted to the rack 8 by the gears 11 and 13, and the rack 8 moves in the front-rear direction,
The rotation of the second motor 10 is rotated by the gears 12 and 14 to the support rod 7.
Is transmitted to the rack at the lower end of the support rod 7 and moves vertically.

Next, a series of control procedures will be described with reference to the flowchart of FIG.

First, when the occupant's seat is detected by a seat sensor (not shown) or the like, distance measurement is performed by both sensors 3 and 4 (step S1), and the distances Ld and Le (see FIG. 4) described above are determined by the ECU 5. (Step S2), the ECU 5 controls both motors 9, 1 so that the distances Ld, Le respectively match the optimum values Ld ', Le'.
0 is controlled (step S3), and the headrest body 6 is moved back and forth and up and down.

Then, the ECU 5 controls the distances Ld 'and Ld
And the difference ΔLd between the distances Le ′ and Le are calculated, and it is judged whether or not these differences ΔLd and ΔLe are both within the allowable range (step S4).
If it is O, the process returns to step S1, and if the determination result is YES, the control of both motors 9 and 10 by the ECU 5 is stopped (step S5), and the headrest body 6 causes the most cervical injury to the occupant's groin. The position is adjusted to the optimum position where the prevention and reduction effects are high, and then the operation ends.

Therefore, since the headrest main body 6 can be automatically adjusted to the optimum position in the vertical direction and the front-back direction with reference to the top of the shoulder close to the position of the base of the neck, the adjustment work is less troublesome than in the conventional case. Therefore, the effect of reducing cervical injury can be improved.

Needless to say, the supporting means and adjusting means of the headrest body are not limited to the configuration of the above embodiment.

Needless to say, the distance measuring sensors 3 and 4 are not limited to the infrared light emitting and light receiving elements described above.

Furthermore, in the above-mentioned embodiment, the case where the invention is applied to the driver's seat has been described, but it goes without saying that the invention can be applied to other seats.

[0025]

As described above, according to the headrest position adjusting device of the present invention, the headrest body is adjusted to the optimum position in the vertical and longitudinal directions with reference to the position of the top of the shoulder close to the position of the root of the neck. Therefore, it is possible to improve the effect of reducing the injury to the cervical part as compared with the related art without requiring the adjustment work as in the related art, and it is extremely effective as a safety improvement measure.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of a headrest position adjusting device of the present invention.

FIG. 2 is a partial perspective view of part of the present invention.

3 is an explanatory diagram of the arrangement of FIG. 1. FIG.

FIG. 4 is an explanatory diagram of the arrangement and operation of FIG.

5 is a flowchart for explaining the operation of FIG.

[Explanation of symbols]

 1 Driver's seat 3,4 1st, 2nd sensor 3a, 4a Infrared light emitting element 3b, 4b Infrared light receiving element 5 ECU 7 Support rod 8 Rack 9,10 1st, 2nd motor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kakichi Ishimori 3000 Yamanoue, Ryuo-cho, Gamo-gun, Shiga Prefecture Daihatsu Industry Co., Ltd. Shiga Technical Center (72) Inventor Noboru Shimamoto 3000, Yamanoue, Ryuo-cho, Gamo-gun, Shiga Prefecture Address inside Shiga Technical Center, Daihatsu Motor Co., Ltd.

Claims (1)

[Claims] 1. A distance measuring sensor, which is provided in a passenger compartment and includes a light emitting element for radiating light to substantially the top of the shoulder of an occupant seated in a seat and a light receiving element for receiving light reflected from the top of the shoulder, and the distance measuring sensor. Calculating means for calculating the distance between the top of the shoulder and the installation position of the sensor based on the timing of light emission and light reception by the distance sensor to derive the position of the top of the shoulder;
Support means movably provided in the up-down and front-rear directions for supporting the headrest body, a drive means for moving the support means, and up-down, front-rear direction of the headrest body with respect to the top of the shoulder by controlling the drive means. And a control means for adjusting the position to the optimum position.