JP2007022450A - Vehicle seat device - Google Patents

Abstract

There is provided a vehicle seat device capable of suitably operating a headrest in accordance with a detected object on the vehicle seat.
A vehicle seat device includes a headrest rear portion supported by a seat back, a headrest front portion that can move forward and backward with respect to the headrest rear portion, and a motor that moves the headrest front portion. A collision determination unit 11 that detects that an impact is applied to the vehicle or that the impact is applied, and a headrest front portion 8 at the time of or before the collision to the vehicle based on a detection signal from the collision determination unit 11 ECU20 which controls the motor 10 so that it may move. The ECU 20 further includes load sensors 13A to 13D that detect load characteristics applied to the vehicle seat 2, and the ECU 20 determines a detection object on the vehicle seat 2 based on the load characteristics, and the headrest front portion 8 according to the determination result. Permit or prohibit movement.
[Selection] Figure 1

Description

  The present invention relates to a vehicle seat device having a headrest.

  2. Description of the Related Art Conventionally, there has been proposed a vehicle seat device including a mechanism for moving a headrest forward of a vehicle so as to protect a passenger's head at the time of a collision from the rear of the vehicle (see, for example, Patent Documents 1 and 2). .

When an impact is applied to the vehicle from the rear, the upper body of the occupant moves rapidly toward the rear seat back in a posture where the upper body of the occupant is not left in the seat back. In this case, the occupant's head is moved by the abrupt movement, moves backward to a position where the headrest is located, and when the headrest comes into contact with the headrest, the backward movement is restricted. Thereafter, the upper body of the occupant is greatly shaken forward due to the reaction caused by the impact force, so that the occupant's neck may be burdened and whipping may occur. Therefore, in such a case, if the headrest is moved forward of the vehicle with respect to the seat back, the head of the occupant is protected from being largely moved rearward, so that the burden on the occupant's neck is reduced. It is reduced. As a result, the occurrence of whipping can be suppressed.
JP 2000-21114 A JP 2003-54343 A

By the way, in the vehicle seat apparatus as described above, it is necessary to reliably protect the head of the occupant regardless of the physique and posture of the occupant seated on the vehicle seat.
For example, if the occupant seated in the vehicle seat is small and the head position does not reach the height of the headrest, the head of the occupant can be protected even if the headrest is moved forward I can't.

  For example, when a child seat (hereinafter referred to as CRS (Child Restraint System)) or a booster seat is mounted on the vehicle seat, and the CRS or booster seat is up to the height of the headrest, the headrest is moved forward to Extruding the member can occur. Even if the headrest can move forward, the headrest can reach the head of the occupant on the CRS or booster seat because the operating state of the headrest is set according to the occupant seated directly on the vehicle seat. could not.

  This invention is made | formed in view of such a situation, The objective is to provide the vehicle seat apparatus which can operate a headrest suitably according to the detected object on a vehicle seat.

  In order to solve the above problems, the invention according to claim 1 is directed to a rear portion of a headrest supported with respect to a seat back, a fully closed position close to the rear portion of the headrest, and a fully opened portion spaced from the rear portion of the headrest. A headrest front portion that is movable back and forth between positions; a drive means that moves the headrest front portion; an impact detection means that detects whether an impact has been applied to the vehicle; or an impact detection means from the impact detection means Control means for controlling the drive means to move the front portion of the headrest in the direction of the fully open position at the time of or before the collision with the vehicle based on the detection signal, A load sensor for detecting a load characteristic applied to the vehicle seat is further provided, and the control means discriminates an object to be detected on the vehicle seat based on the load characteristic. Permits or prohibits the movement of the headrest front portion according to the determination result.

  According to the first aspect of the present invention, the control means discriminates the detected object on the vehicle seat based on the load characteristic applied to the vehicle seat, and permits the movement of the front portion of the headrest according to the discrimination result or Ban. For this reason, the control means permits the movement of the front part of the headrest when the head part is a detection object that is suitably protected by moving the front part of the headrest, and the head part by moving the front part of the headrest. If is not protected, movement of the headrest front can be prohibited. Therefore, the headrest front part can be suitably operated according to the detected object on the vehicle seat.

  The invention according to claim 2 is the vehicle seat device according to claim 1, wherein the control means determines whether the detected object is an adult or a non-adult, and determines that the detected object is an adult. The movement of the front part of the headrest is permitted.

  According to the second aspect of the present invention, when there is an adult on the vehicle seat, the front part of the headrest is moved at the time of the collision from the rear of the vehicle or before the collision. The head of this can be suitably protected and can reduce whipping. The term “adult” refers to an occupant whose head is positioned at substantially the same height as the headrest front.

  According to a third aspect of the present invention, in the vehicle seat device according to the first or second aspect, the control means prohibits the movement of the front portion of the headrest when it is determined that the detected object is other than an adult. .

  According to the third aspect of the present invention, when there is no adult on the vehicle seat, the front part of the headrest is not moved at the time of the collision from behind the vehicle or before the collision. Can be prevented. Further, it is possible to reduce useless operations at the front portion of the headrest. “Non-adult” means that the height of the head is an occupant whose height is different from the front of the headrest, that the occupant on the vehicle seat includes CRS, etc., and that there is no detection object. is there.

According to a fourth aspect of the present invention, in the vehicle seat device according to any one of the first to third aspects, the impact detection means includes the load sensor.
According to the fourth aspect of the present invention, since the impact detection means is constituted by a load sensor, the configuration can be simplified as compared with the case where it is constituted by a separate member.

  According to the present invention, the headrest can be suitably operated according to the detected object on the vehicle seat.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
FIG. 1A is a side view of the vehicle seat device 1, and FIG. 1B is a plan view thereof. The vehicle seat device 1 is arranged on the passenger seat side of the vehicle.

  As shown in FIG. 1A, a vehicle seat device 1 includes a vehicle seat 2, and the vehicle seat 2 includes a seat seat 4 fixed to a seat bracket 3 fixed to the vehicle body, and a seat seat 4 And a headrest 6 supported with respect to the seatback 5.

  The headrest 6 includes a headrest rear portion 7 supported by a headrest stay 5 a provided at the upper end portion of the seat back 5, and a headrest front portion 8 that is movable back and forth with respect to the headrest rear portion 7. The headrest front portion 8 includes a fully closed position 8A close to the headrest rear portion 7 as shown by a solid line in FIG. 1A and a fully open position spaced from the headrest rear portion 7 as shown by a two-dot chain line in FIG. It can be moved forward and backward with respect to the position 8B. During normal operation of the vehicle, the headrest front portion 8 is disposed at the fully closed position 8A.

  As shown in FIGS. 1A and 1B, the vehicle seat device 1 includes a drive mechanism 9 that moves the headrest front portion 8 forward and backward, a motor 10 as a drive unit that drives the drive mechanism 9, and A collision determination unit 11, a head detection sensor 12, four load sensors 13 </ b> A, 13 </ b> B, 13 </ b> D, and 13 </ b> D, and an ECU 20 as a control unit that controls the motor 10 are provided.

  The drive mechanism 9 is configured to move the headrest front part 8 in the advancing and retreating direction by being driven by the motor 10 and extending and contracting between the headrest rear part 7 and the headrest front part 8. The collision determination unit 11 corresponds to an impact detection unit that detects an impact applied to the vehicle or an impact applied to the vehicle. In the present embodiment, the collision determination unit 11 is connected to a radar (not shown) installed in a bumper at the rear of the vehicle, and receives a signal from the radar to input a relative speed / distance to the following vehicle and a vehicle speed. Is comprehensively determined, and it is detected whether or not the following vehicle has collided or there is a possibility of a collision with the following vehicle.

  The head detection sensor 12 detects that the head of an occupant seated on the vehicle seat 2 has contacted the headrest front portion 8. The head detection sensor 12 includes a touch sensor or the like, and is installed on the front surface of the headrest front portion 8.

  The four load sensors 13A, 13B, 13D, and 13D are fixed to the seat bracket 3 and detect load characteristics applied to the vehicle seat 2. In the present embodiment, two load sensors 13A and 13B are provided behind the seat 4 (seat back 5 side), and two load sensors 13D and 13D are provided in front, and these four load sensors 13A and 13B are provided. , 13D and 13D detect the load applied to the seating surface 4a of the seat 4. Each of the load sensors 13A, 13B, 13D, and 13D includes a strain detection element such as a strain gauge, and each load sensor 13A, 13B, 13D, and 13D is detected according to a load applied to the seating surface 4a of the seat seat 4. The amount of bending performed is electrically detected.

  The ECU 20 is connected to the motor 10 and the collision determination unit 11, and based on the detection signal from the collision determination unit 11, the headrest front part 8 is fully opened from the fully closed position 8A at the time of the collision from the rear of the vehicle or before the collision. The motor 10 is controlled to move in the position 8B direction.

  Further, the ECU 20 determines the detected object on the vehicle seat 2 based on the load characteristics detected by the four load sensors 13A, 13B, 13D, and 13D, and moves the headrest front portion 8 according to the determination result. Permit or prohibit.

  Specifically, the ECU 20 determines whether the detected object on the vehicle seat 2 is an adult or a non-adult, and when determining that the detected object is an adult, permits the movement of the headrest front portion 8. The term “adult” refers to an occupant whose head is positioned at substantially the same height as the headrest front.

  Further, when the detected object on the vehicle seat 2 is determined to be other than an adult, the ECU 20 prohibits the movement of the headrest front portion 8. “Non-adult” means that the height of the head is an occupant whose height is different from that of the headrest front portion 8, the occupant on the vehicle seat 2 includes CRS, and the detected object is It is not.

  Further, the ECU 20 moves the headrest front portion 8 when the head of the occupant is detected based on the detection signal from the head detection sensor 12 when moving the headrest front portion 8 toward the fully opened position 8B. Stop. Further, when the occupant's head is not detected, the ECU 20 moves the headrest front portion 8 to the fully open position 8B.

Next, an electrical configuration of the vehicle seat device 1 will be described.
As shown in FIG. 2, the vehicle seat device 1 includes an ECU 20, a motor 10 connected to the ECU 20, four load sensors 13 </ b> A, 13 </ b> B, 13 </ b> D, 13 </ b> D, a head detection sensor 12, a power supply device 14, and a collision determination unit. 11 etc. are comprised.

  The ECU 20 includes a CPU 21, a power supply circuit 22 connected to the CPU 21, a vehicle information input circuit 23, a motor drive circuit 24, a load sensor input circuit 25, a head detection sensor circuit 26, and the like.

  The CPU 21 is connected to the power supply device 14 via an ignition switch (IGSW), and is configured to be supplied with power from the power supply device 14 via the power supply circuit 22 by turning on the ignition switch. Further, the CPU 21 inputs vehicle information such as rear approach information from the collision determination unit 11 via the vehicle information input circuit 23.

  The CPU 21 is connected to the motor 10 via the motor drive circuit 24 and drives the motor 10 by controlling the motor drive circuit 24. The CPU 21 is connected to the four load sensors 13A, 13B, 13D, and 13D via the load sensor input circuit 25, and inputs the detection signals from the four load sensors 13A, 13B, 13D, and 13D, and the seat 4 The detected object on the seat 4 is discriminated based on the load characteristic applied to the seating surface 4a.

  Specifically, the CPU 21 reads load signals from the four load sensors 13A, 13B, 13D, and 13D, and outputs load values for the load sensors 13A, 13B, 13D, and 13D, and a total load value obtained by summing these output load values. Based on the above, the detected object on the seat 4 is discriminated.

  In the present embodiment, the CPU 21 first determines whether or not the detected object is a human body by distributing the detected load values from the load sensors 13A, 13B, 13D, and 13D. In general, when a person is seated on the vehicle seat 2, the person is placed in a posture with his back on the seat back 5, so that the distribution of the detected load values of the load sensors 13 </ b> A and 13 </ b> B arranged at the rear increases. . For this reason, the CPU 21 determines that the detected object is a person when the distribution of the detected load values of the load sensors 13A and 13B arranged rearward with respect to the detected load values of the load sensors 13C and 13D arranged forward is large. To do.

  Further, the CPU 21 compares the detected load values from the four load sensors 13A, 13B, 13C, and 13D with the distribution of the detected load values when the CRS or the booster seat is mounted on the vehicle seat 2. It can be determined that the CRS or the booster seat is attached to the work sheet 2. The booster seat is configured so that a seat or a seat and a backrest can be attached to the vehicular seat 2, and for protecting a small person to sit directly on the vehicular seat 2 like the CRS. It is a sheet.

  When it is determined that the detected object of the seat 4 is a person, the CPU 21 compares a preset threshold value with the total load value. If the total load value is equal to or greater than the threshold value, the detected object is an adult. If the total load is smaller than the threshold value, it is determined that the detected object is a child.

The CPU 21 is connected to the head detection sensor 12 via the head detection sensor circuit 26, and determines whether or not the head has been detected by inputting a detection signal from the head detection sensor 12.
Next, the process which CPU21 of ECU20 of the said vehicle seat apparatus 1 performs is demonstrated.

  As shown in FIG. 3, first, in step 100, the CPU 21 inputs load signals from the four load sensors 13A, 13B, 13D, and 13D. In step 110, the CPU 21 determines whether or not an occupant is seated on the vehicle seat 2 based on the distribution of the load values detected from the four load sensors 13A, 13B, 13C, and 13D. If it is determined that an occupant is seated on the vehicle seat 2 (step 110, YES), the process proceeds to step 120, where the load values input from the load sensors 13A, 13B, 13D, 13D are summed up to obtain a total load value. Is calculated. Further, when it is determined that no occupant is seated on the vehicle seat 2 (step 110, NO), this process is terminated. In this case, a CRS or a booster seat is mounted on the vehicle seat 2 or there is nothing on the vehicle seat 2.

  Next, the CPU 21 proceeds to step 130 and determines whether or not the occupant seated on the vehicle seat 2 is an adult. At this time, the CPU 21 compares the preset threshold value with the total load value calculated in step 120, and determines that the occupant is an adult if the total load value is equal to or greater than the threshold value. If it is small, it is determined that the occupant is not an adult. In this case, an occupant having a physique whose head position does not reach the height position of the headrest front portion 8 is present on the vehicle seat 2.

  When the CPU 21 determines that the occupant is an adult (step 130, YES), the CPU 21 proceeds to step 140, and determines whether there is a vehicle approach or collision based on the detection signal from the collision determination unit 11. If the CPU 21 determines that the occupant is other than an adult (NO at step 130), the CPU 21 ends the process.

  If the CPU 21 determines that there is a rear approach or a rear collision (step 140, YES), the CPU 21 proceeds to step 150 and moves the headrest front portion 8 forward. If it is determined that there is no rear approaching or collision information (step 140, NO), this process is terminated.

  After moving the headrest front portion 8 forward in step 150, the CPU 21 determines in step 160 whether or not there is head detection. If the head is not detected (step 160, NO), the CPU 21 proceeds to step 170, and determines whether or not a predetermined time has elapsed since the headrest front portion 8 started moving forward. This fixed time is, for example, a time during which the headrest front portion 8 becomes a full stroke, and is set to about several seconds. If the predetermined time has not elapsed (step 170, NO), the CPU 21 returns to step 150. If the predetermined time has elapsed (step 170, YES), the CPU 21 proceeds to step 180, stops the movement of the headrest front portion 8, and ends this processing.

  Further, when the head is detected in step 160 (step 160, YES), the CPU 21 proceeds to step 180, stops the movement of the headrest front portion 8, and ends this processing. The CPU 21 repeats the processing from step 100 to step 180 described above while the ignition switch of the vehicle is in the ON state.

Therefore, according to this embodiment, the following effects can be obtained.
(1) The ECU 20 determines a detection object on the vehicle seat 2 based on a load characteristic applied to the vehicle seat 2, and permits or prohibits the movement of the headrest front portion 8 according to the determination result. For this reason, the ECU 20 permits the movement of the headrest front part 8 when the headrest front part 8 is a detected object whose head is suitably protected by moving the headrest front part 8, and the headrest front part 8 is moved. When the head is not protected, the movement of the headrest front portion 8 can be prohibited. Therefore, the headrest front part 8 can be suitably operated according to the detected object on the vehicle seat 2.

  (2) When there is an adult on the vehicle seat 2, the headrest front part 8 is moved at the time of a collision from behind the vehicle or before the collision. It is protected and can reduce whipping.

  (3) When there is no adult on the vehicle seat 2, the headrest front part 8 is not moved at the time of or before the collision to the vehicle, so that it is possible to prevent problems caused by the movement of the headrest front part 8. . Moreover, the useless operation | movement of the headrest front part 8 can be reduced.

In addition, you may change embodiment of this invention as follows.
In the above embodiment, the four load sensors 13A, 13B, 13D, and 13D and the collision determination unit 11 as an impact detection unit that detects a collision or approach to the vehicle are provided separately. Two load sensors 13A, 13B, 13D, and 13D may be used as impact detection means. In other words, a collision or approach from the rear to the vehicle may be detected based on the load characteristics detected from the four load sensors 13A, 13B, 13D, and 13D.

  For example, when the vehicle has a collision from behind and there is a weight shift of the occupant on the seating surface 4a of the seat 4, the load value detected from the load sensors 13A and 13B arranged at the rear of the vehicle than during normal operation. Becomes larger. Therefore, a threshold value corresponding to a load value assumed when an impact is applied to the vehicle from behind is set in advance, and when the load value detected from the load sensors 13A and 13B exceeds the threshold value, What is necessary is just to judge that there was a collision. If comprised in this way, compared with the case where an impact detection means and a load sensor are comprised by another member, a structure can be simplified.

  In the above embodiment, the load sensors 13A, 13B, 13D, and 13D having strain elements such as strain gauges are provided. However, if the load can be detected, the load detecting means uses a piezoelectric effect such as a crystal. You may comprise with other things, such as a pressure sensor.

  In the above embodiment, the case where four load sensors are provided has been described. However, the number of load sensors is not limited to this, and if the detected object on the vehicle seat 2 can be identified, what is the load sensor? You may provide. A pair of load sensors may be provided one by one in the front-rear direction of the vehicle seat 2.

  In the above embodiment, the load sensors 13A, 13B, 13D, and 13D are provided as load sensors that detect the load characteristics applied to the vehicle seat 2, but the load sensors that detect the load characteristics may be in other modes. . For example, an on / off type load sensor is provided in a matrix form on the seating surface 4a of the seat 4 and is discriminated by pattern matching which performs the discrimination by capturing the characteristics of the assumed difference between the CRS and the person. May be. Further, a load sensor may be provided on the seat back 5. In short, it is only necessary that the load sensor can determine whether the detected object on the vehicle seat 2 is an adult or a non-adult.

  In the above embodiment, the case where the headrest front portion 8 is moved by the motor 10 has been described. However, if the headrest front portion 8 can be moved back and forth between the fully closed position 8A and the fully open position 8B, You may comprise the operation | movement system of the part 8 in another aspect. For example, a spring type or a solenoid type may be used.

  In the above embodiment, the headrest 6 is provided with the head detection sensor 12, but the head detection sensor 12 is not necessarily provided. In this case, for example, the moving distance and moving speed of the headrest front part 8 in the fully opened position 8B direction may be set in advance.

In the above-described embodiment, the case where the vehicle seat device 1 is applied to the passenger seat of the vehicle has been described.
The technical idea that can be grasped from the above embodiment will be described below.

  (A) In the vehicle seat device according to any one of claims 1 to 4, the load sensor detects a load applied to a seating surface of the vehicle seat, A front load sensor for detecting a load on the front portion and a rear load sensor for detecting a load on the rear portion of the seating surface, wherein the control means is configured such that the load value detected from the rear load sensor is greater than the front load sensor. The detected object is determined to be an adult when the load value is larger than the load value detected from the partial load sensor and the total value of the load values detected from the load sensors is larger than a predetermined threshold value. Vehicle seat device.

(A) is a side view of a vehicle seat device. (B) is a top view of the vehicle seat apparatus. The block diagram which shows the electric constitution of the vehicle seat apparatus. The flowchart explaining the process which the vehicle seat apparatus performs.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Vehicle seat apparatus, 2 ... Vehicle seat, 4 ... Seat seat, 5 ... Seat back, 6 ... Headrest, 7 ... Headrest rear part, 8 ... Headrest front part, 8A ... Fully closed position, 8B ... Fully open position, 10 ... Motor (drive means), 11... Collision determination unit (impact detection means), 13A, 13B, 13C, 13D... Load sensor, 20.

Claims (4)

A headrest rear portion supported against the seat back;
A headrest front part that is movable forward and backward between a fully closed position close to the rear part of the headrest and a fully open position separated from the rear part of the headrest;
Driving means for moving the front portion of the headrest;
An impact detection means for detecting that an impact is applied to the vehicle or an impact is applied;
Control means for controlling the drive means so as to move the headrest front part in the direction of the fully open position at the time of or before the collision to the vehicle based on the detection signal from the impact detection means;
A vehicle seat device comprising:
A load sensor for detecting a load characteristic applied to the vehicle seat;
The control means determines a detection object on the vehicle seat based on the load characteristic, and permits or prohibits movement of the front portion of the headrest according to the determination result. The vehicle seat device according to claim 1,
The control means determines whether the detected object is an adult or a non-adult, and permits the movement of the front portion of the headrest when determining that the detected object is an adult. The vehicle seat device according to claim 1 or 2,
The control means prohibits movement of the front portion of the headrest when it is determined that the detected object is other than an adult. The vehicle seat device according to any one of claims 1 to 3,
The vehicle seat device according to claim 1, wherein the impact detection means is constituted by the load sensor.

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