JP2009173190A - Seat belt apparatus of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seat belt apparatus of a vehicle capable of minimizing forward displacement of an occupant after rebound in a rear collision, and reducing second collision in a car interior. <P>SOLUTION: The seat belt apparatus 20 of the vehicle 11 comprises: a belt reel 31 for winding a belt 21; an actuator 32 for reeling the belt by rotary drive of the belt reel; and a control device 40 for controlling reeling operation of the belt by the actuator based on a detection signal related to a rear collision state generated in the vehicle, and further comprises a load detection part 51 for detecting a load applied on a seat back 12b of a seat which is equipped with the belt. The control device includes a rear collision belt control part 402 for actuating the actuator when the load detected by the load detection part becomes not less than a predetermined value. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle seat belt device, and more particularly, to a vehicle seat belt device suitable for suppressing forward movement due to rebound by tightening a seat belt at a timing when an occupant moves rearward in a rear collision.

  Conventionally, a seat belt pretensioner device has been put into practical use as a seat belt tightening device in a vehicle seat belt device, and is widely installed in commercial vehicles. The seat belt tightening device includes a collision detection device and a control unit that tightens the seat belt based on a detection signal output from the collision detection device. The seat belt tightening device limits the forward movement of the occupant sitting on the seat and reduces the forward movement amount by removing the slack of the seat belt at the time of the collision.

In the above-described seat belt tightening device, in the case of a rear collision among the collisions, the occupant's rear head and back are restrained or brought close to the seat back immediately before the rear collision or simultaneously with the occurrence of the rear collision. An apparatus for alleviating overextension (backward bending) of parts has been proposed (Patent Documents 1, 2, etc.). These devices include a device for predicting a rear collision or a device for detecting a rear collision, a pretensioner device, and a control device for controlling the operation of the pretensioner device based on the prediction signal or the detection signal. Restrain the movement. The configuration of the conventional apparatus is controlled to operate immediately when a rear collision is predicted or detected, tension is applied to the seat belt to restrain the occupant to the seat back of the seat, and the head to the rear in the passenger compartment. Reduce exercise.
Japanese Patent No. 3721451 Japanese Patent No. 3837909

  In the case of a rear collision, particularly in the case of a rear collision, the occupant moves backward in the passenger compartment due to the acceleration at the time of the collision and is pressed against the seat back of the seat, and then rebounds due to the elasticity of the seat back and moves forward. To do. For this reason, in the second half of the rear collision, there is a possibility that a vehicle interior secondary collision will occur due to rebound. Especially for small passengers or passengers with a physique different from the standard body type, for example, passengers whose chest and abdomen are larger than the average, the distance from the front panel and the steering wheel is already relatively close when seated during normal driving. Therefore, the possibility of contact by rebound is great.

  In consideration of the above-mentioned conventional device, the pretensioner device is operated immediately after the prediction or detection of the rear collision so that the belt tightening control is completed, so that the occupant moves backward after the operation, and as a result, the seat belt There will be slack between the passenger and the passenger. In this regard, the conventional apparatus does not consider at all. Accordingly, it is not possible to expect an effect of sufficiently suppressing the forward movement of the occupant due to the subsequent rebound.

  In addition, the device disclosed in Patent Document 1 described above reduces the belt winding force, that is, the seat belt load, in order to reduce the excessive bending (forward bending) of the neck due to rebound in a state where the occupant is restrained. As a result, the forward movement is further increased.

  In view of the above problems, an object of the present invention is to provide a vehicle seat belt device capable of minimizing the forward movement of an occupant after rebound in a rear collision and reducing a secondary collision in a passenger compartment. It is in.

  In order to achieve the above object, a vehicle seat belt apparatus according to the present invention is configured as follows.

  A seat belt device for a first vehicle (corresponding to claim 1) includes a belt reel around which a belt is wound, an actuator that winds the belt by rotationally driving the belt reel, and a rear collision state that occurs in the vehicle. Control means for controlling the winding operation of the belt by the actuator based on the detection signal, and further comprising load detection means for detecting a load applied to the seat back of the seat equipped with the belt, and the control means Is configured to include a rear collision belt control unit that activates the actuator when the load detected by the load detection unit exceeds a predetermined value.

  In the above-described vehicle seat belt device, for example, when a rear collision such as a rear-end collision occurs in a traveling or stopped vehicle, an occupant sitting on the seat moves rearward by inertial motion based on the load information detected by the load detection means. The belt is tightened at the position moved most backwards. As a result, it is possible to tighten the belt at an optimal timing at the time of a rear collision, to minimize the forward movement of the occupant after rebounding in the rear collision, and to reduce the secondary collision in the vehicle interior.

  The seat belt device of the second vehicle (corresponding to claim 2) is preferably configured such that the load detection means is a load detection means provided inside the seat back.

  A seatbelt device for a third vehicle (corresponding to claim 3) is configured as described above. Preferably, the load detecting means includes a seat lower load detecting means and a vehicle body acceleration detecting means provided at a portion where the seat is attached. The load is calculated from a calculation using the acceleration detection value output from the vehicle body acceleration detection means and the load detection value output from the underseat load detection means.

  In the fourth vehicle seat belt apparatus (corresponding to claim 4), the rear collision belt control means preferably includes load differential value calculation means for calculating a differential value of the load, and the load is detected. The actuator is operated based on the detection signal of the means and the calculated value of the load differential value calculation means.

  In the fifth vehicle seat belt apparatus (corresponding to claim 5), preferably, the rear collision belt control means has a load exceeding a predetermined value and a load differential value is less than a predetermined value. The actuator is sometimes operated.

  A sixth vehicle seat belt device (corresponding to claim 6) detects a belt reel around which a belt is wound, an actuator that winds the belt by rotating the belt reel, and a rear collision of the vehicle. A load for detecting a load applied to the seat back of the seat equipped with the belt, further comprising: a rear collision detection means; and a control means for controlling the winding operation of the belt by the actuator based on a detection signal from the rear collision detection means. The control unit includes a detection unit, and the control unit includes a rear collision belt control unit that operates the actuator when a load detected by the load detection unit exceeds a predetermined value when the rear collision detection unit detects a rear collision. It is comprised so that it may contain.

  In a seventh vehicle seat belt apparatus (corresponding to claim 7), in the above-mentioned configuration, the rear collision belt control means preferably includes load differential value calculation means for calculating a differential value of the load, and detects the load. The actuator is operated based on the detection signal of the means and the calculated value of the load differential value calculation means.

  In the above configuration, the eighth vehicle seat belt device (corresponding to claim 8) is preferably configured such that the rear collision belt control means has a load exceeding a predetermined value and a load differential value falling below a predetermined value. The actuator is sometimes operated.

  A seatbelt device for a ninth vehicle (corresponding to claim 9) is preferably provided with a rear collision prediction means for detecting the possibility of a rear collision of the vehicle in each of the above-mentioned configurations, and the actuator has an explosive thrust. The first actuator that winds the belt using a belt and the second actuator that reversibly winds the belt using the driving force of the motor. Based on the detection signal output from the rear collision prediction means, the second actuator is driven to control the belt to the driving state in the preliminary restrained state, and the rear collision is detected by the rear collision detection means. Sometimes, the drive state is switched to a state in which the output of the second actuator is increased, and the first actuator is driven when the load exceeds a predetermined value. And having a first control means for controlling to.

According to the present invention, in a seat belt device of a vehicle, for example, when a rear collision such as a rear-end collision occurs in a traveling vehicle, the seat belt device sits on a seat based on a load detection function of a load detection unit provided in the seat back When the occupant moved backward by inertial motion and performed the belt tightening operation accurately at the position moved most backward, the belt tightening was performed at the optimal timing in the case of a rear collision, especially when rebound might occur Therefore, the belt restraining the occupant is not slackened, and the forward movement of the occupant after the rebound in the rear collision is suppressed to the minimum, and the secondary collision in the vehicle interior can be reduced.
In particular, it is possible to expect an effect on an occupant having a physique different from a standard physique, for example, a chest and abdomen protruding larger than the average.
Even if the seatbelt load is reduced to allow the occupant to move forward and reduce the forward bending of the neck due to rebound, the occupant must load the belt load from the state where he / she has moved most backward. Since it moves forward while receiving it, more rebound energy can be absorbed, the amount of occupant movement is reduced, and the possibility of a secondary collision in the passenger compartment can be reduced.

  DESCRIPTION OF EMBODIMENTS Preferred embodiments (examples) of the present invention will be described below with reference to the accompanying drawings.

  A first embodiment of a vehicle seat belt apparatus according to the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 shows a schematic overall view of a vehicle as viewed from the side and a configuration of a control device, and FIG.

  The vehicle 11 is a traveling automobile, for example, and shows a state in which an occupant (driver) 13 sits on a driver seat (seat) 12 and is driving the traveling vehicle 11. 11A is a front part of the vehicle body, 11B is a rear part of the vehicle body, 14 is a wheel, and 15 is a steering handle. The seat 12 includes a stool portion 12a on which an occupant 13 sits and a seat back 12b that leans back. A seat belt device 20 is mounted on the driver seat 12. The seat belt device 20 includes a belt (seat belt or webbing) 21 that restrains the body of the occupant 13 to the seat 12. The belt 21 includes a belt portion 21 a that restrains the upper body of the occupant 13 and a belt portion (not shown) that restrains the waist of the occupant 13. One end of the lower side of the belt 21 is fixed to a vehicle body portion at the lower part of the passenger compartment of the vehicle 11 by an anchor plate 22. The upper end portion of the belt portion 21 a is folded back by a through anchor 23 provided near the shoulder of the occupant 13, and the end portion is connected to the belt tightening device 30. The belt tightening device 30 includes a belt reel 31 that is connected to the end of the belt portion 21a and wound thereon, and an actuator 32 that winds the belt 21 by rotationally driving the belt reel 31.

  The actuator 32 of the belt tightening device 30 has the same function as a general pretensioner device. As the actuator 32 of the belt tightening device 30, for example, an explosive device that operates with an explosive thrust, or a response speed smaller than that of the explosive thrust, but a reversible (forward or reverse) winding operation can be performed. An electric motor or the like is used. The actuator 32 can be configured using either one or both of an explosive device and an electric motor.

  The control device 40 is a device that controls the operation of the actuator 32 of the belt tightening device 30. An object of control by the control device 40 is an actuator 32, and the actuator 32 is located on the output side of the control device 40. The control of the belt tightening device 30 by the control device 40 is output from the detection signal output from the load detection unit 51 that detects the load applied to the seat back 12b of the seat 12 and the collision detection unit 52 disposed in the vehicle rear portion 11B. Detection signal.

  The load detection unit 51 is embedded in the seat back 12b. The load detection unit 51 includes a strain gauge type load meter and an amplification circuit. The load detection unit 51 receives a pressing pressure by the backrest action of the occupant 13 and detects the load. In the present embodiment, when a rear collision occurs in the vehicle 11, the occupant 13 sitting on the seat 12 moves backward by an inertial action and presses the seat back 12b. The output signal of the load detection unit 51 is input to the input unit 401 of the control device 40.

  Moreover, the collision detection part 52 is arrange | positioned, for example in center parts, such as a bumper part of a vehicle rear surface part. The collision detection unit 52 installed in the vehicle rear portion 11B is a sensor for detecting a rear collision (or rear collision), and an arbitrary detection mechanism can be provided. The “rear collision” is, for example, a rear-end collision by another vehicle from behind the vehicle 11, and is simply referred to as “rear collision” in the following description. A detection signal output from the collision detection unit 52 is input to the input unit 401 of the control device 40.

  The control device 40 that controls the operation of the actuator 32 of the belt tightening device 30 is configured to include a belt tightening control unit 402. The belt tightening control unit 402 generates and outputs a control command signal based on the detection signal output from the load detection unit 51 and the detection signal output from the collision detection unit 52. A drive signal based on this control command signal is supplied to the actuator 32 via the output unit 403.

  The control device 40 includes an electric circuit portion and a computer portion in actual production. An input / output unit is provided with an I / O circuit. A belt tightening control unit 402 that generates a control command signal based on an input signal is an arithmetic processing unit that executes a program for controlling belt tightening at the time of a rear collision, as will be described later. This arithmetic processing unit is a computer (CPU Etc.). In order to generate a drive signal based on a control command signal output from the belt tightening control unit 402, a power supply circuit, an amplifier circuit, and the like are provided.

  In FIG. 1, for convenience of explanation, the control device 40 is taken out from the outside of the vehicle 11 and illustrated, but actually, it is installed as an electronic control unit at an appropriate location on the vehicle 11.

  When the collision detection unit 52 detects a rear collision, the belt tightening control unit 402 of the control device 40 detects that the load detected by the load detection unit 52 is greater than or equal to a predetermined value (an arbitrary reference value set in advance). It functions to actuate the actuator 32 of the belt tightening device 30. The belt tightening control unit 402 for the vehicle seat belt device 20 according to the present embodiment functions as belt tightening control means (rear collision belt tightening control means) when a rear collision occurs in the vehicle 11. .

  FIG. 2 shows the content of the control calculation processing by the belt tightening control unit 402. In the first step S 11, a load detection signal (load detection value) output from the load detection unit 51 and a rear collision detection signal output from the collision detection unit 52 are input. Next, it is determined whether or not a rear collision has been detected based on the rear collision detection signal (step S12). Next, when YES is determined in the determination step S12, it is determined whether or not the load detection value obtained by the load detection signal is equal to or greater than a predetermined value (F1) (step S13). This “predetermined value (F1)” is preferably a load value detected by the load detection unit 51 based on the pressure when the occupant 13 sitting on the seat 12 moves backward due to a rear collision and moves to the rearmost position. Is set to When the determination in step S13 is YES, a control command signal for operating the actuator 32 is output (step S14).

  According to the configuration of the first embodiment, the belt 21 is tightened in a state in which the occupant 13 moves backward in the passenger compartment and is pressed against the seat back 12b of the seat 12 in the case of a rear collision in the vehicle 11. The belt 21 that restrains the occupant 13 does not sag at the time when the rebound may occur, suppresses the forward movement of the occupant 13 after the rebound, and reduces the secondary collision in the vehicle interior. Can do. Further, even if the seat belt load is reduced to allow the occupant 13 to move forward and the forward bending of the neck due to rebound is reduced, the occupant 13 moves from the state in which the occupant 13 has moved most backward in the passenger compartment. Since the vehicle moves forward while receiving the load caused by the above, more rebound energy can be absorbed, the occupant movement amount can be reduced, and the possibility of a secondary collision in the passenger compartment can be reduced.

  Next, a second embodiment as a modification of the first embodiment will be described with reference to FIG. In the second embodiment, the collision detection unit 52 is omitted, and instead, the belt tightening control is performed based only on the detection signal output from the load detection unit 51. Compared to the first embodiment, the configuration according to the second embodiment is a simplified configuration. Furthermore, the overall apparatus configuration in the second embodiment is the same as that shown in FIG.

  In the control calculation process by the belt tightening control unit 402 according to the second embodiment, a load detection signal (load detection value) output from the load detection unit 51 is input in the first step S21. Next, it is determined whether or not the load detection value obtained from the load detection signal is equal to or greater than a predetermined value (F2) (step S22). This “predetermined value (F2)” is preferably a load value detected by the load detection unit 51 based on a pressure when the occupant 13 sitting in the seat 12 moves backward and moves backward enough to be judged as a rear collision. It is set to be. When YES is determined in the determination step S22, a control command signal for operating the actuator 32 is output (step S23).

  Note that the determination criterion in the determination step S22 may be configured to determine whether or not the integrated value of the load detection value obtained from the load detection signal is equal to or greater than a predetermined value (F3). In this case, an integration processing step (step S24 temporarily shown by a broken line in FIG. 3) for calculating an integral value of the load detection value is provided between the processing step S21 and the determination step S22. The predetermined value (F3) is also set as appropriate according to the integrated value of the load detection value.

  Next, a third embodiment as a modification of the first embodiment will be described with reference to FIG. Even in the third embodiment, the collision detection unit 52 is omitted, and instead, belt tightening control is performed based only on the detection signal output from the load detection unit 51. The overall apparatus configuration in the third embodiment is the same as that shown in FIG.

  In the control calculation process by the belt tightening control unit 402 according to the third embodiment, a load detection signal (load detection value) output from the load detection unit 51 is input in the first step S31. Next, a differential processing step S32 is provided for calculating a differential value of the load detection value (the acting speed of the load). Thereafter, it is determined whether or not the load detection value obtained from the load detection signal is equal to or greater than a predetermined value (F1) (step S33). Thereafter, when YES is determined in the determination step S33, it is determined whether or not the differential value of the load detection value, that is, the load acting speed is equal to or less than a predetermined value as a reference (step S34). When YES is determined in the determination step S34, a control command signal for operating the actuator 32 is output (step S35). A belt tightening control command signal is generated and output only when the load detection value is equal to or greater than the predetermined value and the differential value of the load detection value is equal to or less than the predetermined value. When the differential value of the load detection value is equal to or less than a predetermined value, it is determined that the load is maximum (or maximum). In addition, as a reference for determining that the load is maximum (or maximum), a point in time at which the differential value (time differential value) of the load changes from positive to negative can be used. According to such a control process, even when the receiving pad of the seat back 12b does not bottom out, it is possible to estimate the state in which the occupant has moved to the end.

  In the third embodiment, basically, a configuration is employed in which the actuator is operated based on the load detection signal output from the load detection unit 51 and the load differential value by the load differential value calculation means.

  In the first to third embodiments, the load detection unit 51 provided in the seat back 12b is provided, for example, in a rotation support part of the reclining mechanism of the seat 12, an attachment part below the seat 12, or the like. be able to. Further, instead of the load detection unit 51, an occupant weight detection sensor used for a smart airbag can be diverted.

  A fourth embodiment of a vehicle seat belt apparatus according to the present invention will be described with reference to FIGS. FIG. 5 shows a schematic overall view of the vehicle viewed from the side and the configuration of the control device, and FIG. 6 shows the flow of control executed by the control device. In the configuration of the fourth embodiment, a load detection unit (occupant weight detection unit) 71 provided in an attachment portion below the seat 12 is used instead of the load detection unit 51, and the vehicle 11 is used instead of the collision detection unit 52. A vehicle body acceleration detection unit 72 provided on the front side of the vehicle is used.

  The load (load detection signal SIG11) detected by the load detection unit 71 is a combination of the inertial force generated by the mass of the seat 12 and the load by which the occupant 13 presses the seat back 12b. The vehicle body acceleration detection unit 72 detects acceleration due to a collision in the front-rear direction of the vehicle 11 and outputs an acceleration detection signal SIG12. The longitudinal collision of the vehicle 11 includes the aforementioned rear collision.

  Other configurations are the same as those described with reference to FIG. 1. In FIG. 5, the same elements as those described with reference to FIG. In the belt tightening control unit 402 in the vehicle seat belt device according to the fourth embodiment, a control process as shown in FIG. 6 is executed.

  With reference to FIG. 6, the content of the control arithmetic processing by the belt tightening control unit 402 according to the present embodiment will be described. In the first step S41, a load detection signal SIG11 output from the load detection unit 71 and an acceleration detection signal SIG12 output from the vehicle body acceleration detection unit 72 are input. As described above, the load detection signal SIG11 obtained by the load detection unit 71 according to the present embodiment is a combination of the inertia force generated by the mass of the seat 12 and the load by which the occupant 13 presses the seat back 12b. Therefore, only the load with which the occupant 13 presses the seat back 12b is obtained by the calculation in the next step S42.

  In the calculation of step S42, first, the acceleration (value of the acceleration detection signal SIG12) detected by the vehicle body acceleration detection unit 72 is multiplied by the mass of the seat back 12b, which may occur while the vehicle is running. The inertia force of the seat back 12b is estimated. Next, the estimated inertia force of the seat back 12b is subtracted from the load detection value (the value of the load detection signal SIG11) detected by the load detection unit 71. Thereby, only the load that the occupant 13 presses the seat back 12b, that is, the pressing load value is calculated. This pressing load value corresponds to the load detection value detected by the load detection unit 51 in the first embodiment. Therefore, in the case of the present embodiment, as described in the first embodiment, the pressing load value can be obtained without providing the load detection unit 51 in the seat back 12b.

  Thereafter, as in step S22 in the second embodiment described with reference to FIG. 3, it is determined whether or not the obtained pressing load detection value is equal to or greater than a predetermined value (step S43), and in determination step S43. If YES, a control command signal for operating the actuator 32 is output (step S44). The predetermined value here is a predetermined value corresponding to the case where the occupant 13 sitting on the seat 12 moves backward due to a rear collision and moves to the rearmost position.

  According to the configuration of the fourth embodiment, as in the case of the first embodiment, a state in which the occupant 13 moves rearward in the vehicle interior and is pressed against the seat back 12b of the seat 12 in the rear impact of the vehicle 11. Since the belt 21 is tightened, the belt 21 that restrains the occupant 13 does not become slack at the time when the rebound may occur, and the forward movement of the occupant 13 after the rebound is suppressed, Secondary collision can be reduced. Further, even if the seat belt load is reduced to allow the occupant 13 to move forward and the forward bending of the neck due to rebound is reduced, the occupant 13 moves from the state in which the occupant 13 has moved most backward in the passenger compartment. Since the vehicle moves forward while receiving the load caused by the above, more rebound energy can be absorbed, the occupant movement amount can be reduced, and the possibility of a secondary collision in the passenger compartment can be reduced.

  Next, a fifth embodiment as a modification of the above-described fourth embodiment will be described with reference to FIG. In the fifth embodiment, steps S51 and S52 are added to steps S41 to S44 in the flowchart shown in FIG. Step S51 is provided between Step S42 and Step S43, and Step S52 is provided between Step S43 and Step S44. Steps S41 to S44 are as described above, and a detailed description thereof is omitted here. The overall apparatus configuration in the fifth embodiment is the same as that shown in FIG.

  According to the method of controlling the seat belt device for a vehicle according to the fifth embodiment, the differential value is calculated in the next added step S51 for the pressing load value calculated in step S42. Further, the added determination step S52 determines whether or not the differential value of the pressing load value is equal to or larger than a predetermined value when YES is determined in the determination step S43 in the preceding stage. When the determination in step S52 is YES, a control command signal for operating the actuator 32 is output (step S44).

  In the control method of the fifth embodiment, a belt tightening control command signal is generated and output only when the detected pressure load value is equal to or larger than a predetermined value and the differential value of the pressure load value is equal to or smaller than the predetermined value. To do. When the differential value of the pressing load value is equal to or less than a predetermined value, it is determined that the load is maximum (or maximum). In addition, as a reference for determining that the load is maximum (or maximum), a point in time at which the differential value (time differential value) of the pressing load value changes from positive to negative can be used. According to such a control process, even when the receiving pad of the seat back 12b does not bottom out, it is possible to estimate the state in which the occupant has moved to the end.

  The vehicle seat belt device according to the fifth embodiment can achieve the same effects as those of the above-described embodiment.

  Next, a sixth embodiment of the vehicle seat belt apparatus according to the present invention will be described with reference to FIGS. This embodiment is a modification of the first embodiment. FIG. 8 is a view similar to FIG. 1 and shows a schematic overall view of the vehicle and the configuration of the control device as seen from the side. In FIG. 8, elements substantially the same as those described in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. FIG. 9 is a flowchart showing the control contents. The characteristic components according to the sixth embodiment can be combined with the characteristic components of the second to fifth embodiments.

  In the vehicle seat belt device according to the sixth embodiment, a rear collision prediction device 81 that detects the possibility of a rear collision of the vehicle 11 is provided in the rear portion 11B of the vehicle 11. As the rear collision prediction device 81, the detection function unit is a radar device, a camera device, or the like. In order to predict the rear collision, a calculation process by the control device 40, that is, a computer is required. When the rear collision prediction device 81 predicts the possibility of a collision with a rear vehicle or the like, a control command signal is generated. The belt tightening device 30 includes a first actuator 321 and a second actuator 322. The first actuator 322 is an explosive device that winds the belt 21 using thrust, and the second actuator 321 is an electric motor that reversibly winds the belt 21. The second actuator 321 includes a clutch mechanism and the like. In the belt tightening control by the second actuator 321, the tightening force is preferably set to a load that does not affect the driving operation.

  In addition, the control device 40 includes a first belt tightening control unit 402A and a second belt tightening control unit 402B. The first belt tightening control unit 402A corresponds to the belt tightening control unit 402 described in the first embodiment. Therefore, the configuration and operation of the input unit 401, the first belt tightening control unit 402A, and the output unit 403 are the same as those in the first embodiment. In this case, the input signal is a detection signal from the load detection unit 51 and the collision detection unit 52, and the control target is the first actuator 321. An input unit 411 and an output unit 412 are also provided for the second belt tightening control unit 404B. The second belt tightening control unit 402B receives the prediction detection signal output from the rear collision prediction device 81, drives the second actuator 322 based on the prediction detection signal, and controls belt tightening.

  A control processing flow based on the first belt tightening control 402A and the second belt tightening control unit 402B will be described with reference to FIG. The contents of control by the first belt tightening control 402A are basically the same as those in the first embodiment, and FIG. 9 shows steps S11, S12, S13, and S14 as in FIG. .

  According to the belt control at the time of a rear collision by the vehicle seat belt device according to the sixth embodiment, the control by the second belt tightening control unit 402B is executed in the initial stage. First, the second actuator 322 is driven by the control operation of the second belt tightening control unit 402B based on the detection signal related to the prediction output from the rear collision prediction device 81, so that the belt 21 is brought into a driving state in a preliminary restrained state. To do. That is, a signal output from the rear collision prediction device 81 is input (step S61). Next, in a determination step S62, it is determined whether or not there is a prediction detection signal in the output signal. If NO, the process returns to step S61, and if YES, the next step S63 is executed. In step S63, the operation of the actuator 322 such as an electric motor is controlled based on the read prediction detection signal, and the belt winding amount is adjusted. In this belt tightening control, it is desirable that the tightening force does not affect the driving operation. Thus, the second belt tightening control unit 402B forms a drive mode in a preliminary restrained state.

  Next, in the preliminary restrained state, the belt winding amount is read by the rotation detecting means attached to the rotating shaft or the like of the belt reel (step S64), and the belt winding amount is managed and controlled (step S65). . As the content of management / control of the belt winding amount, for example, the belt winding amount in the preliminary restrained state is controlled to always exceed a certain fixed amount. The reason for this is to ensure the necessary stroke and operation time when the first actuator 321 is operated in the next stage. If the belt winding amount is small and the slack amount is too large, belt slack may occur even if the actuator 321 of the adjusted belt winding amount is operated. Therefore, adjust the belt winding amount appropriately. Keep it.

  Thereafter, the control for belt tightening based on the first belt tightening control unit 402A based on the detection of the rear collision by the collision detection unit 52, that is, the above-described steps S11, S12, S13, and S14 are executed. At this time, when a rear collision is detected, the output of the second actuator 322 is increased and adjusted appropriately in step S65. If NO in the determination step S12, the process returns to the first step S61. Based on step S14, the belt 21 is wound by the thrust of the first actuator 321.

  According to the belt control at the time of rear collision by the seat belt device of the vehicle according to the sixth embodiment, first, based on the detection signal related to the prediction output from the rear collision prediction device 81, the second belt tightening control unit 402B The second actuator 322 is driven by the control operation so that the belt 21 is driven in the preliminary restrained state as described above. In this belt tightening control, it is desirable that the tightening force does not affect the driving operation. Thereafter, when the rear collision is detected by the load detection unit 51 and the collision detection unit 52, the belt 21 is wound by the first belt tightening control unit 402B by the thrust of the first actuator 321.

  In the sixth embodiment, when a gunpowder device is used for the first actuator 321, the first actuator 321 is provided independently of the second actuator 322. In addition, when using an electric motor for the 1st actuator 321, the output state shall be changed appropriately and changed similarly to the case of the explosive device.

  The vehicle seat belt device according to the present invention can be arbitrarily configured as necessary by appropriately combining the characteristic configurations of the first to sixth embodiments.

  The configurations, shapes, sizes, and arrangement relationships described in the above embodiments are merely schematically shown to the extent that the present invention can be understood and implemented. Therefore, the present invention is not limited to the described embodiments, and can be variously modified without departing from the scope of the technical idea shown in the claims.

  The vehicle seat belt device according to the present invention is used to optimally tighten a belt in the case of a rear collision in a passenger car or the like and prevent secondary collision due to rebound.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a first embodiment of a vehicle seat belt device according to the present invention, and is a diagram showing a schematic overall view of a vehicle and an internal configuration of a control device as viewed from the side. It is a flowchart which shows the control content in 1st Embodiment. It is a flowchart which shows the control content in 2nd Embodiment which is a modification of 1st Embodiment. It is a flowchart which shows the control content in 3rd Embodiment which is a modification of 1st Embodiment. FIG. 8 shows a fourth embodiment of a seat belt device for a vehicle according to the present invention, and is a diagram showing a schematic overall view of the vehicle as viewed from the side and an internal configuration of a control device. It is a flowchart which shows the control content in 4th Embodiment. It is a flowchart which shows the control content in 5th Embodiment which is a modification of 4th Embodiment. FIG. 10 shows a sixth embodiment of a seat belt device for a vehicle according to the present invention, and is a diagram showing a schematic overall view of a vehicle and an internal configuration of a control device viewed from a side surface. It is a flowchart which shows the control content in 6th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Vehicle 12 Seat 13 Crew 20 Seat belt device 21 Belt 30 Belt tightening device 31 Belt reel 32 Actuator 40 Control device 51 Load detection unit 52 Collision detection unit 71 Load detection unit 72 Car body acceleration detection unit 81 Rear collision prediction device 402 Belt tightening control 402A First belt tightening control unit 402B Second belt tightening control unit

Claims (9)

A belt reel wound with a belt; an actuator that winds the belt by rotationally driving the belt reel; and the winding of the belt by the actuator based on a detection signal related to a rear collision state generated in a vehicle. In a vehicle seat belt device comprising control means for controlling the operation,
A load detecting means for detecting a load applied to a seat back of a seat equipped with the belt;
The vehicle seat belt device according to claim 1, wherein the control means includes a rear collision belt control means for operating the actuator when the load detected by the load detection means exceeds a predetermined value.   2. The vehicle seat belt device according to claim 1, wherein the load detection means is load detection means provided inside the seat back.   The load detection means includes a lower seat load detection means and a vehicle body acceleration detection means provided at a portion where a seat is attached, and the load includes an acceleration detection value output from the vehicle body acceleration detection means and the lower seat load detection. 2. The vehicle seat belt device according to claim 1, wherein the vehicle seat belt device is calculated from a calculation using a load detection value output from the means.   The belt control means at the time of a rear collision includes a load differential value calculating means for calculating a differential value of the load, and operates the actuator based on a detection signal of the load detecting means and a calculated value of the load differential value calculating means. The vehicle seat belt device according to any one of claims 1 to 3.   The belt control means at the time of a rear collision operates the actuator when the load exceeds a predetermined value and the load differential value falls below a predetermined value. A vehicle seat belt device according to claim 1. A belt reel around which a belt is wound, an actuator that winds the belt by rotating the belt reel, a rear collision detection unit that detects a rear collision of the vehicle, and a detection signal from the rear collision detection unit A seat belt device for a vehicle, comprising: control means for controlling the winding operation of the belt by the actuator based on:
A load detecting means for detecting a load applied to a seat back of a seat equipped with the belt;
The control means includes a belt control means at the time of rear collision that operates the actuator when the load detected by the load detection means exceeds a predetermined value when the rear collision detection means detects the rear collision. A vehicle seat belt apparatus comprising:   The belt control means at the time of a rear collision includes a load differential value calculating means for calculating a differential value of the load, and operates the actuator based on a detection signal of the load detecting means and a calculated value of the load differential value calculating means. The vehicle seat belt device according to claim 6.   The vehicle seat according to claim 6 or 7, wherein the rear collision belt control means operates the actuator when the load exceeds a predetermined value and the load differential value falls below a predetermined value. Belt device. The vehicle further comprises rear collision prediction means for detecting the possibility of a rear collision of the vehicle,
The actuator comprises a first actuator that winds the belt using a propellant of explosives, and a second actuator that reversibly winds the belt using a driving force of a motor,
The rear collision belt tightening control means drives the second actuator based on a detection signal output from the rear collision prediction means, and controls the belt in a preliminarily restrained driving mode. And when the rear collision detection means detects a rear collision, the driving state is switched to a state in which the output of the second actuator is increased, and when the load becomes a predetermined value or more, the first The vehicle seat belt device according to any one of claims 1 to 8, further comprising first control means for controlling the actuator so as to drive the actuator.

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