JP2007245814A - Seat belt control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seat belt control device capable of operating a pretensioner mechanism if a collision even with an obstacle in an area outside a detection area is predicted, and reducing the sense of incongruity on an occupant by the operation of the pretensioner mechanism. <P>SOLUTION: A PCS/ACC controller 8 operates a first pretensioner mechanism 2c when a collision of a vehicle V with an obstacle detected by an obstacle detection sensor 4 is predicted, and a predetermined tension is given to a webbing 2a. The obstacle moving from the detection area A into an estimated area B provided adjacent to the outer side of the detection area A is estimated by an obstacle estimation unit 84. When the collision of the estimated obstacle with the vehicle V is predicted, the first pretensioner mechanism 2c is operated to give the second tension smaller than the first tension to the webbing 2a. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention includes a seat belt that includes a pretensioner mechanism that applies a predetermined tension to the webbing, and operates the pretensioner mechanism when a collision of the host vehicle is predicted to restrain the occupant with the predetermined tension. The present invention relates to a control device.

  Conventionally, a seat belt control that includes a pretensioner mechanism that applies a predetermined tension to the webbing and operates the pretensioner mechanism when a collision of the host vehicle is predicted to restrain the occupant with the predetermined tension. The device is known.

  For example, in the seatbelt control device disclosed in Patent Document 1, a millimeter wave radar is provided at a substantially central portion in the vehicle width direction of the front end of the host vehicle, and emits millimeter waves toward the front of the host vehicle from the millimeter wave radar. Thus, an obstacle existing in front of the host vehicle is detected. When the seat belt control device predicts a collision between the obstacle detected by the millimeter wave radar and the host vehicle, the seat belt control device operates the pretensioner mechanism to notify the occupant that there is a risk of collision with the obstacle. In addition to warning, the occupant is restrained in advance in preparation for a collision.

The millimeter-wave radar has a detection area having a radial shape that spreads around the millimeter-wave radar, and detects an obstacle present in the detection area.
JP 2004-136785 A

  By the way, the seatbelt control device according to Patent Document 1 predicts a collision only with respect to the obstacle in the detection area, operates the pretensioner mechanism, and the obstacle existing outside the detection area. Not considered.

  However, even if an obstacle exists outside the detection area, the possibility of collision with the host vehicle is not zero. For example, when the detection area has a radial shape like the millimeter wave radar, the area outside the detection area does not detect an obstacle even in the area immediately in front of the host vehicle. Such an area is located closer to the end of the vehicle width direction with respect to the own vehicle, so even if there is an obstacle, it is unlikely to collide with the vehicle, but since it is an area immediately in front of the own vehicle, There is some chance of collision between the obstacle and the vehicle. That is, it is necessary to prepare for the collision by operating the pretensioner mechanism by predicting the collision even for an obstacle outside the detection area of the millimeter wave radar.

  On the other hand, obstacles that exist outside the detection area are not as likely to collide with the host vehicle as obstacles that exist within the detection area. In addition, there is a high possibility that the obstacle moving relatively from the detection area to the outer area is an obstacle that has already been recognized by the driver and is about to avoid a collision. In other words, obstacles outside the detection area are not as likely to collide as obstacles in the detection area.Therefore, if the pretensioner mechanism was activated in the same way as the obstacles in the detection area, the pretensioner mechanism There is a risk of causing the passenger to feel uncomfortable due to excessive operation.

  As described above, it is necessary to operate the pretensioner mechanism by predicting a collision even with respect to an obstacle outside the detection area. On the other hand, if the pretensioner mechanism is excessively operated, there is a problem in that an occupant feels uncomfortable.

  The present invention has been made in view of such a point, and an object of the present invention is to operate a pretensioner mechanism when a collision is predicted even for an obstacle existing outside the detection area. At the same time, it is intended to reduce a sense of discomfort to the passenger due to the operation of the pretensioner mechanism.

  The present invention provides a predetermined estimation area adjacent to the outside of the detection area where the obstacle detection means can detect the obstacle, and when a collision with the obstacle estimated in the estimation area is predicted, The tension applied to the webbing is set to be smaller than when a collision with an obstacle detected in the detection area is predicted, and the pretensioner mechanism is operated.

  Specifically, in the first invention, a predetermined tension is applied to an obstacle detection unit that detects an obstacle existing in a predetermined detection area in front of the host vehicle and a webbing that restrains an occupant seated on the seat. A pretensioner mechanism; and a collision prediction unit that activates the pretensioner mechanism to apply a predetermined first tension to the webbing when a collision between the obstacle detected by the obstacle detection unit and the host vehicle is predicted. The seat belt control device provided is an object. Then, by moving relative to the host vehicle, an obstacle that has entered the estimation area provided adjacent to the outside of the detection area from the detection area is detected in the detection area. The vehicle is further provided with obstacle estimation means for estimating based on the information at the time, and the collision prediction means has detected a collision between the obstacle estimated by the obstacle estimation means and the host vehicle within the detection area. It is predicted based on the time information, and when the collision is predicted, the pretensioner mechanism is operated to apply a second tension smaller than the first tension to the webbing.

  In the case of the above configuration, the obstacle in the detection area is detected by the obstacle detection means, and when a collision with the obstacle is predicted by the collision prediction means, the pretensioner mechanism is activated, It is restrained by webbing with a predetermined first tension. As a result, the occupant can be restrained in advance in preparation for a collision, and a sensation alarm can also be performed.

  Further, in the above configuration, the estimation area is provided adjacent to the outside of the detection area, and obstacles entering the estimation area from the detection area by moving relative to the host vehicle are The obstacle estimation means estimates based on information when detected in the detection area. Then, when the collision with the estimated obstacle is predicted by the collision prediction means, the pretensioner mechanism is operated, and the occupant is restrained by webbing with a predetermined second tension. As a result, even if the obstacle exists outside the detection area, the obstacle can be restrained in advance in preparation for a collision by operating the pretensioner mechanism. A bodily sensation alarm can also be performed. At this time, the tension applied to the webbing is set to a second tension smaller than the first tension when the pretensioner mechanism is operated with respect to the obstacle in the detection area, thereby preparing for a collision. The restraining force of the occupant can be reduced, and the uncomfortable feeling to the occupant can be reduced.

  In a second aspect based on the first aspect, the obstacle detection means is a millimeter wave radar.

  In a third aspect based on the second aspect, the millimeter wave radar is disposed at a front end of the host vehicle and is configured to radiate millimeter waves radially toward the front of the host vehicle. , At least a portion on the front side in the irradiation direction of the millimeter wave has a radial shape corresponding to the millimeter wave irradiated radially, and the estimation region is a portion on the front side in the irradiation direction of the millimeter wave in the detection region. It is assumed that it is provided adjacent to the outside in the vehicle width direction.

  When having a detection area having a radial shape corresponding to the radially irradiated millimeter wave as in the above-described configuration, the vehicle width direction of the radiation area in the front side of the radial direction of the detection area of the detection area The area adjacent to the outside is located closer to the end in the vehicle width direction than the position where the millimeter wave radar is disposed with respect to the own vehicle, and obstacles existing in such an area are about to avoid collision by the driver's operation. There is a high possibility that it is an obstacle. However, the possibility of a collision is not zero. Therefore, even if the obstacle is outside the detection area, it is possible to prepare for an emergency collision by operating the pretensioner mechanism by predicting the collision with respect to the obstacle in the estimation area.

  However, the possibility that the obstacle in the estimation area will collide is not zero, but the possibility of collision as described above is low. Therefore, when operating the pretensioner mechanism for the obstacle in the estimation region, by operating the pretensioner mechanism with a second tension smaller than that for operating the pretensioner mechanism for the obstacle in the detection region. , The feeling of strangeness given to the occupant can be reduced.

  According to a fourth invention, in any one of the first to third inventions, the estimation region has an end on the outer side in the vehicle width direction defined by the vehicle width of the host vehicle, and is greater than the vehicle width of the host vehicle. Assume that it is an inner area.

  Since obstacles existing outside the vehicle width of the host vehicle are unlikely to collide with the host vehicle, in the case of the above configuration, the outer end of the estimation area in the vehicle width direction is defined by the vehicle width of the host vehicle. By setting the estimated area to be an area inside the vehicle width of the host vehicle, obstacles that have almost no possibility of colliding with the host vehicle are excluded from the target to operate the pretensioner mechanism. The operation frequency of the vehicle can be suppressed and a sense of discomfort to the occupant can be reduced.

  According to a fifth invention, in any one of the first to fourth inventions, a collision between the obstacle detected by the obstacle detection means or the obstacle estimated by the obstacle estimation means and the host vehicle is avoided. A collision avoidance detecting means for detecting that the collision has been detected, and when the collision avoidance is detected by the collision avoidance detecting means after operating the pretensioner mechanism, the collision prediction means The operation shall be released.

  In the case of the above configuration, when the collision avoidance detection unit detects the avoidance of the collision between the obstacle and the host vehicle, the operation of the pretensioner mechanism is released by releasing the operation of the pretensioner mechanism. By making it as short as possible, it is possible to reduce a sense of discomfort to the passenger.

  According to the present invention, when the collision between the obstacle detected in the detection area and the host vehicle is predicted, the pretensioner mechanism is operated so as to apply the first tension to the webbing, thereby preparing for the collision. Thus, the passenger can be restrained in advance and a sensation warning can be performed. In addition, when an obstacle entering the estimated area adjacent to the outside of the detection area is estimated and a collision between the estimated obstacle and the host vehicle is predicted By operating the pretensioner mechanism so that the second tension smaller than the first tension is applied to the webbing, the occupant is restrained and an unpleasant feeling given to the occupant is reduced in case of a collision. can do.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a vehicle V equipped with a seat belt control device according to an embodiment of the present invention. The vehicle V includes a seat belt device 2 (shown only on the driver's seat side) provided in a driver's seat and a passenger seat, and four brake devices 3 (shown only on the left front side). Only the left front side is shown), an obstacle detection sensor 4 for detecting an obstacle in front of the vehicle, a meter unit 11 and an alarm buzzer 12 provided on the instrument panel 10, and a control unit 5 for controlling them. Yes. The vehicle V controls the vehicle speed so as to automatically travel, and detects or estimates an obstacle ahead of the vehicle, and the seat belt device 2 and the brake device 3 based on the detection and estimation results. PCS (Pre-Crash Safety System) control that operates is performed.

  The seat belt device 2 includes a webbing 2a for restraining an occupant seated in each seat, a retractor 2b provided on a center pillar (not shown) and having a guide drum (not shown) for winding the webbing 2a, and a webbing 2a. And a seat belt pretensioner 20 for applying a predetermined tension. The retractor 2b has a winding amount detection sensor (not shown) that detects the winding amount of the webbing 2a. The seat belt pretensioner 20 is provided integrally with the rear surface of the retractor 2b, and a first pretensioner mechanism 2c that winds the webbing 2a and applies a predetermined first tension to the webbing 2a that is larger than normal. And a second pretensioner mechanism 2d that is integrally provided on the front surface of the retractor 2b, winds the webbing 2a, and applies a predetermined third tension larger than the first tension to the webbing 2a. The first pretensioner mechanism 2c includes an electric motor (not shown), and winds and pulls out the webbing 2a by driving the electric motor. On the other hand, the second pretensioner mechanism 2d includes an inflator (not shown), and the webbing 2a is wound up at a speed higher than the winding speed of the first pretensioner mechanism 2c by operating the inflator.

  The brake device 3 is a hydraulic brake having a disc rotor 3a, a caliper 3b, and a brake assist mechanism 31 including valves such as a pressurizing valve (not shown) and a pressure reducing valve (not shown). The brake device 3 is actuated by the hydraulic pressure of a master cylinder (not shown) generated through a booster (not shown) by depressing a pedal (not shown), and a braking force is applied to the wheels W.

  The brake assist mechanism 31 includes valves such as a pressure valve and a pressure reducing valve, and brakes based on a detection signal from a brake pressure sensor 32 that includes a hydraulic pressure sensor that detects the hydraulic pressure of the master cylinder. By calculating the pedal depression amount and the depression speed, it is detected that the brake pedal has been depressed in an emergency, and when it is detected that the brake pedal has been depressed in an emergency, each valve is controlled and supplied to the brake device 3 A predetermined large braking force is generated by controlling the hydraulic pressure.

  The obstacle detection sensor 4 is mounted at a substantially center in the vehicle width direction at the front end of the vehicle V so that the radar shaft faces the front front of the vehicle V, and radiates millimeter waves radially within a predetermined angle range in front. In addition, this is a scan-type millimeter wave radar that detects the distance, angle, relative speed, and relative moving direction to the obstacle based on the reflected wave from the obstacle present in front of the vehicle V. More specifically, as shown in FIG. 2, the obstacle detection sensor 4 has a detection area A having a radial shape corresponding to the millimeter wave irradiated radially, and detects an obstacle present in the detection area A. can do. The obstacle detection sensor is not limited to the millimeter wave radar, and a radar such as a laser radar or an ultrasonic radar can also be employed.

  As shown in FIG. 3, the control unit 5 includes a PCM (PowerTrain Control Module) 6 that controls the power train of the vehicle V, and a braking force that suppresses the skidding of the vehicle V and maintains the running stability of the vehicle V. And the DSC (Dynamic Stability Control) controller 7 for controlling the engine output and the PCS control, the vehicle control of the vehicle V, specifically, the vehicle speed of the vehicle V is controlled to drive the vehicle V at a constant speed, or to the preceding vehicle. A PCS / ACC controller 8 that performs ACC (Adaptive Cruse Control) control, and a pretensioner controller 9 that receives the control signal from the PCS / ACC controller 8 and controls the seat belt device 2. Communication is established via a CAN (Control Area Network) built in the vehicle V.

  The PCM 6 receives a detection signal from an accelerator opening sensor 61 that detects an accelerator opening when an occupant (driver) of the vehicle V depresses an accelerator pedal and an instruction signal from the PCS / ACC controller 8. Based on the detection signal or the instruction signal, a control signal is output to the throttle 62 to accelerate and decelerate the vehicle V. Further, the PCM 6 receives operation signals from the ACC operation switch 63 for performing ACC control, and these operation signals are output to the PCS / ACC controller 8 via CAN.

  The ACC operation switch 63 is provided on the steering wheel 13 and includes a plurality of switches for performing ACC control. For example, when an ACC main switch that executes and stops ACC control, a set switch that sets a set speed for constant speed control, a coast switch that decelerates the set speed, a cancel switch that interrupts ACC control, and when ACC control is interrupted It consists of a resume switch for restarting ACC control again, an accelerator switch for increasing the set speed, a target inter-vehicle distance setting switch for setting the target inter-vehicle distance with the preceding vehicle in the follow-up control, and the like.

  The DSC controller 7 includes a brake pedal switch 71 that detects that the brake pedal has been operated, a steering angle sensor that detects a steering angle of the steering wheel 13, a yaw rate sensor, a lateral acceleration sensor, a throttle opening sensor, not shown. An output signal from a wheel speed sensor or the like is input, and a control signal is output to the PCM 6 based on information obtained from the signal to control the engine output, and a control signal is output to the brake device 3 to perform braking. The assist mechanism 31 is operated to control the braking force to each wheel W. Thus, the skidding of the wheel W is suppressed and the traveling state is stabilized.

  The PCS / ACC controller 8 receives the signal from the PCS on / off switch 81, the operation signal from the ACC operation switch 63 via the PCM 6, the detection signal from the vehicle speed sensor 82 and the obstacle detection sensor 4, and the ACC Control and PCS control are performed.

  The PCS / ACC controller 8 executes ACC control when receiving an operation signal (signal indicating that ACC control is executed) from the ACC main switch of the ACC operation switch 63, and there is a preceding vehicle in the ACC control. When not, constant speed control is performed to drive the vehicle V at a constant target speed, and tracking control is performed to follow the vehicle V while maintaining a constant target inter-vehicle distance with respect to the preceding vehicle when there is a preceding vehicle. Do.

  In the constant speed control, the PCS / ACC controller 8 controls the PCM 6 so that the vehicle speed of the vehicle V becomes the target vehicle speed set by the occupant based on the operation signal from the ACC operation switch 63 and the detection signal from the vehicle speed sensor 82. An acceleration / deceleration instruction signal is output to control the throttle 62, and a deceleration instruction signal is output to the DSC controller 7 to control the brake device 3 to drive the vehicle V at the target vehicle speed.

  In the follow-up control, the PCS / ACC controller 8 determines the distance between the vehicle V and the preceding vehicle based on the operation signal from the ACC operation switch 63, the detection signal from the vehicle speed sensor 82, and the detection signal from the obstacle detection sensor 4. The brake device 3 is controlled by outputting an acceleration / deceleration instruction signal to the PCM 6 and controlling the throttle 62 and outputting a deceleration instruction signal to the DSC controller 7 so that the distance becomes the target inter-vehicle distance set by the occupant. Thus, the vehicle V is allowed to follow the vehicle while maintaining the target inter-vehicle distance from the preceding vehicle.

  The constant speed control can be performed only when there is no preceding vehicle in front of the vehicle V. When there is a preceding vehicle, the control is automatically switched to the follow-up control.

  Further, the PCS / ACC controller 8 executes PCS control by receiving an ON signal from the PCS ON / OFF switch 81. The PCS / ACC controller 8 includes an obstacle detection unit 83 that detects an obstacle present in the detection area A based on a detection signal of the obstacle detection sensor 4, and an estimation area adjacent to the outside of the detection area A. B (see FIG. 2), an obstacle estimation unit 84 for estimating obstacles existing in the vehicle, a collision between the obstacle V detected by the obstacle detection unit 83 and the vehicle V, and the obstacle estimation unit 84 A collision prediction unit 85 for predicting a collision between the obstacle and the vehicle V, an operation control unit 86 for operating the pretensioner mechanism 2c and the brake device 3 when a collision is predicted by the collision prediction unit 85, A collision avoidance detection unit 87 that detects that the collision between the obstacle predicted by the collision prediction unit 85 and the vehicle V is avoided is provided. This PCS / ACC controller 8 constitutes a collision prediction means.

  The obstacle detection unit 83 is configured to detect an obstacle in a predetermined detection area A in front of the vehicle V shown in FIG. 2 based on a detection signal of the obstacle detection sensor 4. The detection area A is not limited to the shape shown in FIG. 2, and any shape can be adopted. For example, the region outside the vehicle width of the vehicle V is unlikely to travel, and the possibility of collision with an obstacle present in this region is low. May be defined by a width substantially the same as the vehicle width of the vehicle V, and an obstacle existing in a region within the vehicle width of the vehicle V may be detected. Also, the collision time can be easily avoided so that the vehicle V reaches the front end of the detection area A so that unnecessary PCS control is not performed when the distance from the obstacle is wide enough to avoid the collision easily. It may be defined by a distance that can be a predetermined time, and may be configured to detect an obstacle present in an area within this distance. The obstacle detection unit 83 and the obstacle detection sensor 4 constitute an obstacle detection unit.

  As shown in FIG. 2, the obstacle estimation unit 84 is located in front of the vehicle V and is located on both outer sides in the vehicle width direction of the detection area A having a radial shape, and the end on the vehicle width direction outer side is the vehicle. An obstacle that has predetermined estimated areas B and B defined by a vehicle width of V, and has entered the estimated areas B and B from the detection area A by moving relative to the vehicle V Estimate things. Specifically, based on the detection signal from the obstacle detection sensor 4 when detected in the detection area A, the relative speed and the relative movement direction when moving from the detection area A to the estimation area B are calculated. The position in the estimation area B is estimated from the relative speed and the relative movement direction. That is, the obstacle detection sensor 4 detects an obstacle in the detection area A every control cycle, and the obstacle moving in the detection area A by moving relative to the vehicle V is detected every control cycle. Are detected at different positions in the detection area A. The relative speed and relative movement direction of the obstacle can be calculated from the position information of the detected obstacle. Then, the relative speed and the relative movement direction of the obstacle when leaving the detection area A are calculated based on the detection signal at the last detection in the detection area A and the detection signal one cycle before. Based on the relative speed and relative movement direction when the obstacle leaves the detection area A, and the elapsed time since the detection area A is left, the obstacle exists in the estimation areas B and B. It is estimated whether it exists or where it exists if it exists. That is, it is possible to estimate whether or not an obstacle moving from the detection area A exists in the estimation areas B and B. When the driver changes the vehicle speed, the relative speed is corrected based on a detection signal from a vehicle speed sensor or the like, or the relative movement direction is determined based on a state quantity indicating the turning state of the vehicle V such as a yaw rate. The accuracy of estimation can be improved by correcting. This obstacle estimation part 84 comprises an obstacle estimation means.

  The collision predicting unit 85 first travels the vehicle V if the vehicle V and the obstacle continue to move relatively from the relative speed and the relative movement direction of the obstacle based on the detection signal from the obstacle detection sensor 4. It is determined whether there is a possibility of collision on the road. Next, the time until the vehicle V collides with the obstacle that may collide is calculated, and it is predicted that the vehicle V and the obstacle collide when the time until the collision is within a predetermined time. To do. The obstacle estimated in the estimation area B by the obstacle estimation unit 84 is determined from the relative speed and the relative movement direction when the relative movement from the detection area A to the estimation area B is performed.

  When the collision prediction unit 85 predicts a collision with an obstacle, the operation control unit 86 outputs an operation signal to the pretensioner controller 9 to operate the first pretensioner mechanism 2c, and the DSC controller 7 A deceleration instruction signal is outputted to actuate the brake assist mechanism 31 to actuate the brake device 3 so as to decelerate the vehicle V at a predetermined first deceleration. In addition, the driver is notified that the possibility of a collision is high by controlling the meter unit 11 and the alarm buzzer 12. In this way, a sensation warning is given to the occupant, the occupant is restrained in advance, and the vehicle speed is reduced. Furthermore, when the operation control unit 86 receives a collision detection signal from the collision detection sensor 88, the operation control unit 86 outputs an operation signal to the pretensioner controller 9 to operate the second pretensioner mechanism 2d and to the DSC controller 7 a deceleration instruction signal. And the brake assist mechanism 31 is operated to operate the brake device 3 so as to decelerate the vehicle V at a second deceleration greater than the first deceleration. Thus, the impact force on the occupant at the time of collision is reduced as much as possible.

  The collision avoidance detection unit 87 is configured so that the collision detection signal is not input from the collision detection sensor 88 even if the time until the vehicle V collides with an obstacle calculated by the collision prediction unit 85 has elapsed. V determines that a collision with an obstacle has been avoided.

  The pretensioner controller 9 operates the first pretensioner mechanism 2 c and the second pretensioner mechanism 2 d of the seat belt device 2 based on the operation signal from the PCS / ACC controller 8. The collision avoidance detection unit 87 constitutes a collision avoidance detection unit.

  Specifically, when operating the first pretensioner mechanism 2c, the first pretensioner mechanism 2c is operated by controlling the current supplied from the power source 96 and energizing the electric motor of the first pretensioner mechanism 2c, The webbing 2a is wound with a predetermined tension. When the second pretensioner mechanism 2d is operated, the starter is output to the inflator of the second pretensioner mechanism 2d to activate the inflator and wind the webbing 2a with a tension greater than that of the first pretensioner mechanism 2c. Let me take it.

  Hereinafter, the operation control of the seat belt device by the PCS / ACC controller 8 will be described with reference to the flowchart of FIG.

  This flow starts when the PCS on / off switch 81 is turned on.

  First, in step S <b> 1, the obstacle detection unit 83 determines whether an obstacle is detected in the detection area A based on a detection signal from the obstacle detection sensor 4. When an obstacle is detected (YES), the process proceeds to step S2, while when an obstacle is not detected (NO), the process returns to step S1 and repeats step S1.

  In step S2, the collision prediction unit 85 determines whether or not there is a possibility of collision between the obstacle detected in the detection area A and the vehicle V, and the time until the collision is a predetermined first time. It is determined whether it is within T1. When there is a possibility of collision and the time until the collision is within the first time T1 (YES), the process proceeds to step S3. On the other hand, when at least one of the conditions is not satisfied (NO), the process proceeds to step S8.

  In step S3, an alarm is given. Specifically, the operation control unit 86 causes the brake device 3 to intermittently generate a predetermined deceleration. By doing so, it is possible to alert the occupant that the vehicle V may collide with an obstacle ahead. Furthermore, a sign indicating that the possibility of a collision is high is blinked on the meter unit 11 and a buzzer sound indicating that the possibility of a collision is high is sounded on the alarm buzzer 12.

  Thereafter, a collision is predicted in step S4. Specifically, it is determined whether or not the time until the collision is within a predetermined second time T2 shorter than the first time T1. When the time until the collision is within the second time T2 (YES), the process proceeds to step S5, while when the time until the collision is longer than the second time T2 (NO), the process proceeds to step S8. The second time T2 is a time when it is difficult to avoid a collision and the possibility of a collision is high.

  In step S5, the operation control unit 86 operates the first pretensioner mechanism 2c so as to apply a predetermined first tension to the webbing 2a. Further, the operation control unit 86 operates the brake device 3 to generate a predetermined first deceleration to decelerate the vehicle V. Thus, the vehicle V can be decelerated to avoid a collision with an obstacle, and the occupant can be restrained in advance by applying the first tension to the webbing 2a to reduce the impact force when the vehicle collides. Also, restraining the occupant in this way also becomes a sensation alarm.

  Thereafter, in step S6, it is determined whether a release condition for the first pretensioner mechanism 2c is satisfied. Here, the release condition is that the vehicle V has passed while avoiding a collision with an obstacle, and the collision detection signal from the collision detection sensor 88 even if the second time T2 has elapsed after the determination in step S4. It is determined that the collision with the obstacle is avoided when there is no input. When the release condition is satisfied (YES), the process proceeds to step S7. When the release condition is not satisfied (NO), the process returns to step S5 and steps S5 and S6 are repeated. If a collision occurs, the PCS control is terminated at that time. The release condition is not limited to the fact that no collision detection signal is input from the collision detection sensor 88, and any condition can be adopted as long as it can be determined that the first pretensioner mechanism 2c is not required to operate. Can do. For example, it may be a condition that a predetermined time that will surely pass if a collision is avoided passes.

  In step S7, the electric motor of the first pretensioner mechanism 2c is reversely rotated so that the normal tension acts on the webbing 2a to release the operation of the first pretensioner mechanism 2c. Then, it returns to step S1 and repeats from the detection of an obstacle again.

  On the other hand, it is determined that there is no possibility of collision with the obstacle detected in step S2 and / or the time until the collision is longer than the first time T1 (NO), or the time until the collision is the first time in step S4. In step S8, which has been determined to be longer (NO) than 2 hours T2, the obstacle detection unit 83 continues the obstacle in the detection area A based on the detection signal from the obstacle detection sensor 4. It is determined whether it is detected. Here, when NO is determined in step S2 or step S4, the obstacle is detected in the detection area A but the collision is not predicted, and when it is continuously detected. If (YES), the process returns to step S1 to repeat the above flow, while if not continuously detected (NO), the process proceeds to step S9.

  In step S9, the obstacle estimation unit 84 determines whether an obstacle existing in the estimation area B is estimated. When an obstacle is estimated in the estimated area B (YES), the process proceeds to step S10. On the other hand, when an obstacle is not estimated in the estimated area B (NO), the process returns to step S1 and the process proceeds to step S10. Repeat the flow.

  When the obstacle that has moved relative to the detection area A is estimated in the estimation area B, the collision prediction unit 85 determines that the obstacle V and the vehicle V are estimated in the estimation area B in step S10. It is determined whether or not there is a possibility of a collision, and it is determined whether or not the time until the collision is within a predetermined first time T1. When there is a possibility of collision and the time until the collision is within the first time T1 (YES), the process proceeds to step S11, and when at least one of the conditions is not satisfied (NO), the process proceeds to step S16.

  The contents of steps S11 to S15 are the same as the contents of steps S3 to S7 when an obstacle is detected in the detection area A, except for step S13.

  Step S13 is a step in which an alarm is issued in step S11 and the first pretensioner mechanism 2c is operated after a collision is predicted in step S12. Unlike the step S5, which is a similar step, the operation control unit 86 includes The first pretensioner mechanism 2c is operated so that a predetermined second tension smaller than the first tension is applied to the webbing 2a. Further, the operation control unit 86 operates the brake device 3 to generate a predetermined second deceleration smaller than the first deceleration to decelerate the vehicle V. In this way, the vehicle V can be decelerated to avoid a collision with an obstacle, and the occupant can be restrained in advance by applying tension to the webbing 2a to reduce the impact force when the vehicle collides. Same as step S5. However, the tension applied to the webbing 2a and the deceleration generated in the brake device 3 are set smaller than those in step S5. By doing so, a sense of incongruity to the occupant when the first pretensioner mechanism 2c and the brake device 3 are actuated on the obstacles in the estimation regions B and B is reduced.

  On the other hand, it is determined that there is no possibility of collision with the obstacle detected in step S10 and / or the time until the collision is longer than the first time T1 (NO), or the time until the collision is the first time in step S12. In step S16, which has been determined to be longer (NO) than 2 hours T2, the collision avoidance detection unit 87 avoids the collision of the vehicle V with the obstacle estimated in the estimation region B. It is determined whether or not it has passed. Specifically, the vehicle V avoids a collision with an obstacle when there is no input of a collision detection signal from the collision detection sensor 88 even if the time until the collision calculated in step S10 or S12 elapses. It is determined that it has passed. When it is determined that the collision has been avoided (YES), the process returns to step S1 and the above-described flow is repeated. On the other hand, when it is not determined that the collision is avoided (NO), the process returns to step S10 to confirm again the possibility of the collision.

  Thus, while the PCS on / off switch 81 is on, the PCS control is repeated according to the above flow unless it collides with an obstacle. When the PCS on / off switch is turned off 81, the PCS control is stopped.

  When the vehicle V collides with an obstacle, the second pretensioner mechanism 2d is operated and the brake device 3 is operated so as to generate a third deceleration larger than the first deceleration. By doing so, the impact force on the occupant at the time of the collision can be reduced as much as possible.

  Therefore, according to the above-described embodiment, when an obstacle is detected in the detection area A and a collision with the obstacle is predicted, the first pretensioner mechanism 2c is configured to apply the first tension to the webbing 2a. By actuating the occupant, it is possible to restrain the occupant in advance in preparation for a collision with an obstacle and to provide a sensation alarm.

  Further, even if the obstacle is estimated within the estimation area B even outside the detection area A, and the collision with the estimated obstacle is predicted, the first tension is applied so as to apply the second tension to the webbing 2a. By operating the pretensioner mechanism 2c, although it is unlikely to collide with the obstacle, it is possible to restrain an occupant in advance and to be able to give a sensation alarm in case of a collision.

  Further, when the pretensioner mechanism 2c is operated with respect to the obstacle in the estimation region B, a second tension smaller than the first tension when the pretensioner mechanism 2c is operated with respect to the obstacle in the detection region A is applied. By giving to the webbing 2a, when the pretensioner mechanism 2c is operated with respect to the obstacle in the estimation area B that is less likely to collide with the obstacle in the detection area A, the uncomfortable feeling given to the occupant is reduced. Can do.

  Further, as shown in FIG. 2, the detection area A is set as an area radially extending from the obstacle detection sensor 4, and the estimation areas B and B are disposed on both outer sides in the vehicle width direction of the radial shape portion of the detection area A. By setting the areas adjacent to each other and inside the vehicle width of the vehicle V, these estimation areas B and B are set in areas just in front of the vehicle V but close to the end in the vehicle width direction. become. Therefore, there is a high possibility that an obstacle moving from the detection area A to the estimation area B is an obstacle that is about to be avoided by the driver's control, and such an obstacle can collide. It is an obstacle that has a low possibility but a non-zero possibility. Therefore, by predicting the collision and operating the first pretensioner mechanism 2c against the obstacle moving from the detection area A into the estimation area B set as described above, the outside of the detection area A is detected. Even an obstacle can be prepared for an emergency collision. However, since collision is highly likely to be avoided, the tension applied to the webbing 2a is smaller than the first tension when the first pretensioner mechanism 2c is operated on the obstacle in the estimation region B as described above. By setting the second tension, the uncomfortable feeling given to the occupant can be reduced.

  As described above, the present invention includes a pretensioner mechanism that applies a predetermined tension to the webbing, and activates the pretensioner mechanism when a vehicle collision is predicted to restrain the occupant with the predetermined tension. This is useful for the seat belt apparatus configured as described above, and is particularly useful for a seat belt apparatus for operating a pretensioner mechanism by predicting a collision even with an obstacle outside the detection region.

1 is a schematic side view showing a vehicle equipped with a seat belt device according to an embodiment of the present invention. It is an image figure which shows the detection area and estimation area | region of an obstruction detection sensor. It is a block diagram which shows the control system of a seatbelt apparatus. It is a flowchart of the operation control of a seatbelt apparatus.

Explanation of symbols

A Detection area B Estimation area V Vehicle (own vehicle)
2 Seat belt device 2a Webbing 2c First pretensioner mechanism (pretensioner mechanism)
4 Obstacle detection sensor (obstacle detection means)
8 PCS / ACC controller (collision prediction means)
83 Obstacle detection unit (obstacle detection means)
84 Obstacle estimation unit (obstacle estimation means)
87 Collision avoidance detection unit (collision avoidance detection means)

Claims (5)

Obstacle detection means for detecting an obstacle present in a predetermined detection area ahead of the host vehicle, a pretensioner mechanism for applying a predetermined tension to a webbing for restraining an occupant seated on the seat, and the obstacle detection means A seatbelt control device comprising: a collision prediction unit that activates the pretensioner mechanism to apply a predetermined first tension to the webbing when a collision between a detected obstacle and the host vehicle is predicted.
When an obstacle that has entered the estimation area provided adjacent to the outside of the detection area from the detection area is detected in the detection area by moving relative to the host vehicle It further comprises an obstacle estimation means for estimating based on the information of
The collision prediction means predicts a collision between the obstacle estimated by the obstacle estimation means and the host vehicle based on information when it is detected in the detection area, and when the collision is predicted, A seat belt control device, wherein a pretensioner mechanism is operated to apply a second tension smaller than the first tension to the webbing. In the seatbelt control device according to claim 1,
The obstacle detection means is a millimeter-wave radar, and a seat belt control device. In the seat belt control device according to claim 2,
The millimeter wave radar is disposed at the front end of the host vehicle, and is configured to radiate millimeter waves radially toward the front of the host vehicle.
The detection region has a radial shape corresponding to the millimeter wave that is irradiated radially, at least on the front side of the irradiation direction of the millimeter wave,
The seat belt control device according to claim 1, wherein the estimation area is provided adjacent to an outer side in a vehicle width direction of a portion of the detection area on the front side in the millimeter wave irradiation direction. In the seatbelt control device according to any one of claims 1 to 3,
The seat belt control device according to claim 1, wherein the estimated area is an area inside the vehicle width of the host vehicle, the end of the vehicle width direction outer side being defined by the vehicle width of the host vehicle. In the seatbelt control device according to any one of claims 1 to 4,
A collision avoidance detecting means for detecting that the obstacle detected by the obstacle detecting means or the obstacle estimated by the obstacle estimating means and the collision between the host vehicle and the vehicle is avoided;
The collision prediction unit releases the operation of the pretensioner mechanism when the collision avoidance is detected by the collision avoidance detection unit after the pretensioner mechanism is operated.

Images