JP2009190515A - Vehicular occupant protection system and vehicular occupant protection control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular occupant protection system and a vehicular occupant protection control device, preventing the upper body of a seated person from being thrown out of a seat back returned to a basic posture even if the seat back is returned to the basic posture as quickly as possible. <P>SOLUTION: The vehicular occupant protection system is provided with: a collision predicting means for predicting collision; and a control means for controlling the operation of an actuator changing a seat back posture between a basic posture preparing against collision and a reclining posture oscillated in the direction of a flat posture from the basic posture. When a collision prediction is outputted, the actuator is operated in a high-speed returning mode so as to return the back seat at high speed to a semi-basic posture which is just before the basic posture, and the actuator is operated in a low-speed returning mode whose operational speed is lower than the high-speed returning mode to return the seat back from the semi-basic posture to the basic posture. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle occupant protection system for changing a posture of a reclining seat back to a basic posture suitable for anti-collision for protecting a seated occupant when a collision is predicted in a vehicle having a collision prediction function, and The present invention relates to a vehicle occupant protection control device.

  In general, in vehicles such as automobiles, in order to ensure the safety of passengers seated in the seat in the event of an emergency such as a collision, the vehicle structure and seat structure are taken into consideration, and protective devices such as airbags and seat belts are effectively operated. The structure to let you adopt is adopted. However, such safety measures are generally taken so as to function most effectively when the seat back has a preset basic posture suitable for anti-collision. Therefore, when the seat back is in a reclining posture that deviates from the basic posture at the time of collision prediction, it is important to return the seat back to the basic posture before the collision. Since the time from the occurrence of collision prediction to the collision is extremely short, the seat back must be returned to the basic posture in a short time. For this reason, a vehicle occupant protection system that returns the reclining posture to the basic posture at a higher speed than the normal posture changing speed in an emergency in which a collision is predicted has been proposed (see, for example, Patent Document 1).

Japanese Patent Laying-Open No. 2006-8026 (paragraph numbers 0010-0012, FIG. 3)

The configuration in which the seat back is returned from the reclining posture to the basic posture in an emergency is a great advantage for occupant protection in the event of a collision, and it is desirable to return to the basic posture as quickly as possible to prepare for an emergency such as a collision. For this reason, the motor is driven at full power to move the seat back at a high speed, and there is a possibility that a large impact may occur when the seat back is stopped in the basic posture. Further, when the seat back is stopped, a large forward inertial force acts on the seat occupant, so that the upper body of the seat occupant from the seat back, particularly the head, may be greatly separated from the headrest. From the viewpoint of protecting the seated person, it is required that the seated person is in close contact with the seat back in the basic position, and when the seat back returns to the basic position, the body of the seated person should not jump out of the seat back. There must be.
In view of the above situation, the object of the present invention is to reduce the impact when returning to the basic posture in spite of returning the seat back to the basic posture as soon as possible in order to prepare for an emergency such as a collision. It is an object of the present invention to provide a vehicle occupant protection system and a vehicle occupant protection control device in which the upper body of a seated person does not jump out of the seat back returned to the state.

  In order to solve the above-described problems, a vehicle occupant protection system according to the present invention is suitable for a collision prediction means for predicting a collision, a seat having a swingable seat back, and the posture of the seat back for collision. An actuator-driven reclining mechanism that changes between a basic posture and a reclining posture that swings from the basic posture to the flat posture direction; and a control means that controls the operation of the actuator of the reclining mechanism, and the collision prediction means When the collision prediction is output, the control means operates the actuator in a fast return mode so as to return the seat back to the quasi-basic posture before the basic posture at a high speed, and further from the quasi-basic posture to the basic posture. Operates in low-speed return mode, which is slower than the high-speed return mode, so that the posture can be returned with low impact. So, it is configured so as to stop in the basic position.

  According to this configuration, when the collision prediction is output, the actuator is driven at a high speed in the high-speed return mode, and the seat back is moved at a high speed until the quasi-basic attitude is almost close to the basic attitude. When the seat back reaches the quasi-basic position, the actuator is driven at a low speed in the low speed return mode, which is lower than the high speed return mode, and the seat back that has reached the basic position is stopped with a low impact. Accordingly, when the seat back is stopped in the basic posture, a large inertial force does not act on the seated person, so that the seated person can be maintained in contact with the seat back in the basic position. That is, in the present invention, it is not only intended to return the seat back to the basic posture in the shortest time, but it is important to keep the seated person in close contact with the seat back in the basic posture even at the expense of a slight delay time. As a result, an overall better occupant protection system for vehicles has been realized.

  In order to reduce the impact when the seat back stops in the basic posture and to reduce the inertial force acting on the seated person, it is advantageous to decelerate the seat back before the basic posture. For this reason, as one of the suitable forms of the vehicle occupant protection system according to the present invention, the actuator is subjected to deceleration control in the low-speed return mode. The application of deceleration control at a stage past the quasi-basic posture is particularly advantageous when a configuration in which the stop of the seat back in the basic posture is forcibly performed by a mechanical stopper is adopted. is there. The quick return movement of the seat back in an emergency has a considerably large kinetic energy, but the kinetic energy can be reduced as much as possible before contact with the stopper by this deceleration control.

  When a configuration in which the seat back is stopped in a basic posture by a mechanical stopper is adopted, the position control of the seat back in the reclining seat is not designed with high accuracy. Therefore, in general, it is difficult to control the speed of the seat back by feedback control while always detecting the position of the seat back. For this reason, as one preferred embodiment, it is proposed that the control means performs deceleration control of the actuator so that the speed becomes equal to or less than a predetermined speed including zero when the seatback is expected to reach the basic posture. Since the angle range between the basic posture and the quasi-basic posture is known in advance, a deceleration pattern can be set so as to be equal to or less than a predetermined speed including zero at the time when the basic posture is expected to be reached. Therefore, if this characteristic configuration is adopted, the seat back stops immediately before the basic posture without the assistance of the stopper or the small movement is performed by controlling the deceleration with this deceleration pattern when the quasi-basic posture is reached. Energy is applied to the stopper to stop at the basic posture. Accordingly, it is possible to avoid a situation in which the upper body of the seated person jumps out of the seat back when the seat back is stopped at the basic posture or almost the basic posture in order to prepare for an emergency such as a collision.

  Furthermore, the present invention also includes a vehicle occupant protection control device incorporated in the vehicle occupant protection system described above. In other words, the vehicle occupant protection control device according to the present invention drives and controls the actuator that swings the seat back of the vehicle seat, and the posture of the seat back is changed from the basic posture suitable for anti-collision and the flat posture from this basic posture. Control means for changing between the reclining posture swinging in the direction, and when the collision prediction signal is output from the collision prediction means for predicting a collision, the control means moves the seat back to the basic posture. The actuator is operated in a fast return mode so as to return to the near quasi-basic posture at a high speed, and in a low speed return mode that is slower than the fast return mode so as to return from the quasi-basic posture to the basic posture with a low impact. Operate and stop in the basic position. In the vehicle occupant protection control device having such a characteristic configuration, when the collision prediction signal is output, the control means drives the actuator at a high speed in the fast return mode, and the seat back has a quasi-basic attitude that is substantially close to the basic attitude. Move fast until When the seat back reaches the quasi-basic posture, the control means drives the actuator at a low speed in the low speed return mode, which is lower than the high speed return mode, and stops the seat back that has reached the basic posture with a low impact. Thereby, since a large inertia force does not act on the seat occupant when the seat back is stopped in the basic posture, the seat occupant can be maintained in contact with the seat back in the basic posture. In other words, the control of the vehicle occupant protection control device according to the present invention is not only intended to return the seat back to the basic posture in the shortest time, but is seated on the seat back in the basic posture at the expense of some delay time. By placing importance on keeping the person in close contact with each other, overall better occupant protection for vehicles is realized.

  Hereinafter, an embodiment in which a vehicle occupant protection system for a vehicle according to the present invention is applied to an automobile seat will be described with reference to the drawings. 1 and 2 are a side view and a perspective view showing a seat 1 of a vehicle occupant protection system according to the present embodiment, and FIG. 3 is a control block diagram of the vehicle occupant protection system for a vehicle according to the present embodiment. In the present embodiment, the seat 1 exemplifies a driver's seat on which the driver gets on, but is not limited thereto, and can be applied to a seat on the passenger seat side.

  As shown in FIGS. 1 and 2, the seat 1 according to the present embodiment includes a seat back 10, a seat cushion 11, and a headrest 12. The seat back 10 is supported by the seat cushion 11 via a predetermined fulcrum 13 so as to be swingable (turnable within a predetermined range), and the tilt angle of the seat back 10 with respect to the seat cushion 11 can be changed by the reclining mechanism 2. It is. The seat cushion 11 is attached to the floor surface of the vehicle through a seat slide mechanism 14 so as to be slidable in the front-rear direction. Further, a front vertical mechanism (not shown) is provided at the front portion of the seat cushion 11, and the amount of vertical protrusion of the front portion of the seating surface can be changed.

  The vehicle occupant protection system according to the present embodiment is a so-called pre-crash seat system that returns the seat cushion 2 to a posture position suitable for protecting a seated person in an emergency such as when a vehicle collision is predicted. In this application, the posture of the seat cushion 2 suitable for the seated person with respect to the collision is referred to as a basic posture, and the posture up to the prone posture is referred to as a reclining posture. Note that a posture slightly swung from the basic posture in the flat posture direction is particularly referred to as a quasi-basic posture. The collision prediction is output not only in a vehicle collision but also in an emergency situation such as a rollover or rollover.

The reclining mechanism 2 includes a reclining motor 20 as an actuator that operates in accordance with a drive signal from an occupant protection ECU 50 that is a vehicle occupant protection control device incorporating a control means, and a transmission mechanism (not shown). This transmission mechanism has a known structure, and changes the rotational force from the reclining motor 20 to a force that swings the seat back 10 around the fulcrum 13. As the seat back 10 swings as the reclining motor 20 rotates, the posture of the seat back 10 can be changed between the basic posture and the reclining posture.
The seat slide mechanism 14 can also slide the seat cushion 11 in the front-rear direction by a seat slide motor 14 a that operates according to a control signal from the occupant protection ECU 50.

  The reclining mechanism 2 is further provided with a reclining angle detection sensor 21 as posture detection means for detecting the swing angle of the seat back 10. The seat slide mechanism 14 is also provided with a slide position detection sensor 14b for detecting the slide position of the seat cushion 11 in the front-rear direction. For the reclining angle detection sensor 21 and the slide position detection sensor 14b, for example, an angle measuring device such as a potentiometer or a rotary encoder, or a length measuring device such as a linear potentiometer or a linear encoder can be used.

  Further, the seat 1 is provided with an operation switch unit 15 provided with various seat operation switches including a reclining operation switch 22 for setting the seat back 10 in an arbitrary posture through the reclining mechanism 2. An operation signal corresponding to the operation amount or operation time of each operation switch of the operation switch unit 15 is input to the occupant protection ECU 50.

  Furthermore, a collision prediction sensor 41 which is one of the components of the collision prediction means 4 is provided at an appropriate location of the vehicle. The collision prediction sensor 41 is configured using, for example, a millimeter wave radar or an image recognition device that detects an obstacle present around the vehicle. An output signal from the collision prediction sensor 41 is input to the driving situation ECU 40. In the driving situation ECU 40, information such as the distance to the obstacle and the relative speed is calculated based on the output signal from the collision prediction sensor 41, and the vehicle is operated under certain judgment conditions based on the information. The possibility of a collision is evaluated. When the collision prediction is evaluated, the collision prediction information is output from the driving situation ECU 40 to the occupant protection ECU 50.

  The driving situation ECU 40 is also used to ensure the stability of the vehicle by detecting the side slip of the front wheels and the rear wheels of the vehicle using sensors and controlling the brakes of the wheels and the output of the engine. Even when this vehicle stability control is required, it can be determined that there is a possibility of a vehicle collision, so that it is also possible to create collision prediction information. Accordingly, in the present embodiment, the collision prediction sensor 41, a group of sensors for vehicle stability control, and the driving situation ECU 40 that determines the possibility of a vehicle collision based on these sensor signals are included in the collision of the present invention. The prediction means 4 is configured.

  The occupant protection ECU 50 includes a power supply circuit 51 connected to a battery and an ignition switch, a collision prediction information input unit 52 connected to the driving situation ECU 60, a control unit 53, a motor drive circuit 54 connected to the reclining motor 20, A sensor input circuit 55 connected to the reclining angle detection sensor 21 and a switch signal input circuit 57 connected to the operation switch unit 15 are provided.

  The control unit 53 that functions as a core element of the control means of the present invention is substantially constituted by a microcomputer, and creates various functions by an installed program. The functions particularly relevant to the present invention include a seat back attitude calculation unit 531 that calculates the attitude of the seat back 10 based on sensor information from the sensor input circuit 55 and switch state information from the switch signal input circuit 57, and a motor drive circuit. 54 includes a motor control unit 532 that outputs a motor control signal and a motor drive mode determination unit 533 that determines a control mode for the reclining motor 20.

  The motor drive mode determined by the motor drive mode determination unit 533 is divided into a normal mode and an emergency mode, and this emergency mode includes a fast return mode and a low speed return mode. The normal mode is a mode that is selected when a collision prediction is not output from the collision prediction means 4. In this normal mode, the motor control unit 532 controls the reclining motor 20 at an appropriate speed based on an operation signal from the reclining operation switch 22 operated by a seated person, and sets the seat back 10 to a desired posture. The emergency mode is a mode selected when a collision prediction is output from the collision prediction means 4. In this emergency mode, in order to return the seat back 10 to the basic posture at high speed, the reclining motor 20 is operated at full power from the reclining posture to the semi-basic posture, and the seat back 10 is softened from the semi-basic posture to the basic posture. A low-speed return mode in which the reclining motor 20 is operated at a low speed for landing (slow rocking) is combined. In this embodiment, since the reclining motor 20 is duty controlled, the reclining motor 20 is driven at full duty in the fast recovery mode. In the low speed return mode, the reclining motor 20 is driven by deceleration control that continuously decreases the duty ratio.

  As described above, the vehicle occupant protection system according to the present embodiment includes the collision prediction means 4 for predicting the collision. When the collision prediction means 4 outputs the collision prediction, the reclining posture of the seat back 10 is first set at high speed. Move to quasi-basic position at high speed in return mode. Thereafter, the seat back 10 is returned to the basic posture suitable for the collision while decelerating in the low speed return mode, and the seated person is held by the seat back 10 to prepare for the collision.

  Next, an emergency posture change control routine for the seat back 10 in preparation for a collision will be described with reference to a schematic diagram showing a process of transition from the reclining posture to the basic posture of the seat back 10 in FIG. 4 and a flowchart in FIG. . This emergency posture change control routine includes a control process in which the reclining motor 20 is operated in the high speed return mode and the low speed return mode.

  When this emergency posture change control routine starts, initial setting is first performed (# 01). In the initial setting, each timer, each flag, and variable values are reset. A typical timer used here is a return timer that defines the drive time limit of the reclining motor 20 in the emergency mode. Even if the seat back 10 does not reach the basic posture, the reclining motor 20 is stopped as an abnormal state when the drive time limit has elapsed even if the seat back 10 does not reach the basic posture. Typical flags used here are a return flag and a deceleration flag. The return flag is in its ON state (for example, flag value = “1”), and indicates that the emergency posture changing operation of the seat back 10 is being executed in the fast return mode or the deceleration return mode. The deceleration flag indicates that the deceleration posture changing operation of the seat back 10 from the quasi-basic posture to the basic posture in the deceleration return mode is being executed in the ON state.

  When the initial setting is completed, first, a collision prediction is output from the driving situation ECU 40, and it is checked whether or not the collision prediction is confirmed by the occupant protection ECU 50 (# 02). When the collision prediction is not output (# 02 No branch), the state of the return flag is checked (# 03). If the value of the return flag is not “1” (No branch at # 03), the emergency posture changing operation is not executed at this time, and the process returns to step # 02. If the value of the return flag is “1” in step # 03 (# 03 Yes branch), the sudden collision prediction output is canceled during execution of the high-speed return operation of the seat back 10 in the emergency mode. Therefore, after performing additional processing as necessary, assuming that the rapid return control is canceled, for example, the emergency posture change control routine is restarted from the beginning, and the process returns to step # 01.

  If a collision prediction is output at step # 02 (# 02 Yes branch), the state of the return flag is checked (# 04). When the value of the return flag is “0” (# 04 Yes branch), is the current angle of the seat back 10 calculated by the seat back posture calculating unit 531 an area where the seat back 10 should be returned to the basic posture? It is checked (# 05). If the current angle of the seat back 10 is the angle of the basic posture, it is of course unnecessary to return the seat back 10 to the basic posture. Further, when the seat back 10 is in an extremely flat posture, and the high speed return from the posture to the basic posture may cause another problem such as entanglement of the seat belt, the seat back 10 is moved to the basic posture. Restoration is prohibited. Accordingly, when the current angle of the seat back 10 is in such a basic posture return prohibition region (# 05 Yes branch), the fast return control is not started and the process returns to step # 02.

  When the current angle of the seat back 10 is not within the basic posture return prohibition region (# 05 No branch), for example, in the reclining posture as shown in FIG. 4A, the reclining motor 20 in the fast return mode. To start high-speed return of the seat back 10 (# 06). Since the reclining motor 20 is configured to be duty-controlled, a full-duty drive signal is given from the motor drive circuit 54. Since the high-speed return operation of the seat back 10 has started, “1” is set in the return flag (# 07), the return timer is started (# 08), and the process returns to step # 02.

Since “1” is set in the return flag in step # 07, No branch is made in the status check of the return flag in step # 04. In this embodiment, the drive time limit T of the reclining motor 20 for the high speed return of the seat back 10 in the emergency mode is set. Therefore, the timer value of the return timer is compared with this drive limit time: T (# 09).

  When the timer value of the return timer does not exceed the drive limit time: T (# 09 No branch), the current angle of the seat back 10 calculated by the seat back attitude calculation unit 531 reaches the quasi-basic attitude of the seat back 10. Is checked (# 18). As long as the seat back 10 has not reached the quasi-basic position (# 10 No branch), the high speed movement of the seat back 10 in the fast return mode continues through the step # 02 Yes branch, the step 04 No branch, the # 09 No branch, and the # 10 No branch. Is done.

  When the current angle of the seat back 10 calculated by the seat back posture calculating unit 531 reaches the quasi-basic posture of the seat back 10, the movement of the seat back 10 is changed from the fast return mode to the low speed return mode. The posture of the seat back 10 at the time of switching from the high speed mode to the low speed return mode is illustrated in FIG. 4B. By the deceleration movement of the seat back 10 in the low speed return mode to be performed next (c) in FIG. ) Return to the basic posture illustrated in (1).

  If the quasi-basic posture of the seat back 10 has been reached, the Yes branch is made at step # 10 to check the state of the deceleration flag (# 11). If the value of the deceleration flag is not “1” (# 20 No branch), the deceleration movement of the seat back 10 in the low speed return mode has not yet started. Accordingly, the occupant protection ECU 50 starts the deceleration control of the reclining motor 20 by giving the reclining motor 20 a deceleration pattern in which the duty ratio continuously decreases for the deceleration movement (# 12). When deceleration control as the low-speed return mode is started, “1” is set to the deceleration flag (# 13), and the process returns to step # 02.

  When the deceleration control is started, the value of the deceleration flag becomes “1”. Therefore, No branch is made at step # 11, and the current angle of the seat back 10 calculated by the seat back attitude calculation unit 531 is It is checked whether the basic posture has been reached (# 15). When the seat back 10 has returned to the basic posture (# 15 Yes branch), the power supply to the reclining motor 20 is stopped (# 16), and the process returns to step # 01. If the seat back 10 has not returned to the basic posture (# 18 No branch), the process returns to step # 02 in order to continue the deceleration control as the low speed return mode.

  In addition, when the timer value of the return timer exceeds the drive limit time: T during the return operation of the seat back 10 in the emergency mode described above (# 09 Yes branch), a reclining motor is used to stop the return operation in the emergency mode. Power supply to 20 is stopped (# 16), and the process returns to step # 01, or emergency evacuation abnormality recovery processing is performed.

  As described above, the combination of the high-speed return operation in the high-speed return mode and the deceleration operation in the low-speed mode for soft landing to the reference posture makes it possible to return the seat back 10 to the basic posture as soon as possible. Thus, it is possible to realize a vehicle occupant protection system in which the upper body of the seated person does not jump out of the seat back that has returned to the basic posture.

[Another embodiment]
In the description of the above embodiment, the movement of the back seat 10 from the quasi-basic posture to the basic posture in the low speed return mode is performed by position control using the swing angle of the seat back 10 calculated by the seat back posture calculating unit 531. I was going. Instead, a threshold value C as a deceleration control prediction time required from the quasi-basic posture to the basic posture is set in advance, and the back seat 10 is moved from the quasi-basic posture to the basic posture for that time. You may carry out by time control. A flowchart of the emergency posture change control routine in this case is shown in FIG. Here, a deceleration timer for measuring the estimated deceleration control time required from the quasi-basic attitude to the basic attitude is employed. Accordingly, the flowchart of FIG. 6 is different from the flowchart of FIG. 5 in that step # 14 for starting the deceleration timer is added after step # 13. Further, the content of step # 15 is not a determination as to whether or not the back seat 10 has reached the basic posture, but a determination as to whether or not the value of the deceleration timer exceeds a threshold value C. As a result, the control in the low speed return mode ends after the time defined by the threshold value C has elapsed since the back seat 10 reached the quasi-basic posture.

  As an actuator for swinging the seat back 10, it is possible to use an electric cylinder and other driving devices in addition to the motor. The vehicle occupant protection system of the present invention can also be used as a preliminary operation of other occupant protection systems (for example, an air bag, a seat belt with a pretensioner, an active headrest, etc.).

The side view which shows an example of the reclining seat which is the control object of the passenger protection system for vehicles by this invention 1 is a perspective view of the seat according to FIG. The control block diagram in one embodiment of the vehicle occupant protection system by this invention The schematic diagram which shows the form which transfers to the basic position from the reclining attitude | position of the reclining seat which is the control object of the vehicle occupant protection system by this invention The flowchart which shows an example of the emergency posture change control routine used with the vehicle occupant protection system by this invention Flowchart sheet showing different examples of the emergency posture change control routine used in the vehicle occupant protection system according to the present invention

Explanation of symbols

1: Seat 2: Reclining mechanism 4: Collision prediction means 10: Seat back 20: Reclining motor (actuator)
21: Reclining angle detection sensor (attitude detection means)
40: Driving situation ECU
50: Occupant protection ECU (vehicle occupant protection control device)

Claims (4)

Collision predicting means for predicting a collision, a seat having a swingable seat back, a basic posture suitable for pairing with the posture of the seat back, and a reclining posture swinging from this basic posture in a flat posture direction An actuator-driven reclining mechanism that changes between, and a control means for controlling the operation of the actuator of the reclining mechanism,
When a collision prediction is output by the collision prediction unit, the control unit operates the actuator in a high-speed return mode so as to return the seat back to the quasi-basic position before the basic position at a high speed. A vehicle occupant protection system that is operated in a low-speed return mode that is slower than the high-speed return mode so as to return from the basic posture to the basic posture with a low impact, and is stopped in the basic posture.   The vehicle occupant protection system according to claim 1, wherein the actuator is subjected to deceleration control in the low-speed return mode. 3. The vehicle occupant protection system according to claim 2, wherein the control unit performs deceleration control of the actuator so that the speed becomes equal to or less than a predetermined speed including zero when the seatback is expected to reach the basic posture. The actuator that swings the seat back of the vehicle seat is driven and controlled, and the posture of the seat back is changed between a basic posture suitable for anti-collision and a reclining posture swinging from the basic posture to the flat posture direction. A vehicle occupant protection control device including a control means,
When a collision prediction signal is output from the collision prediction unit for predicting a collision, the control unit causes the actuator to return to the quasi-basic position before the basic position at a high speed return mode. A vehicle occupant protection control device that is operated, further operated in a low-speed return mode that is slower than the high-speed return mode so as to return from the quasi-basic posture to the basic posture with a low impact, and stopped in the basic posture.

Images