JP5531051B2 - Seat belt retractor - Google Patents

Description

  The present invention relates to a seat belt retractor installed in a vehicle.

  BACKGROUND ART A seat belt device provided in a vehicle seat is a device that restrains an occupant's rapid movement due to an acceleration generated at the time of a vehicle collision and thereby makes the occupant's body safe. This seat belt device generally includes a seat belt, a seat belt retractor, a buckle device, and the like.

  The retractor winds a seat belt around a winding member (spool) and pulls it in by a spring force, and normally accommodates the seat belt in the retracted state. When the occupant wears a seat belt, the seat belt accommodated is pulled out by pulling the tongue plate provided at one end opposite to the seat belt winding side, and this is engaged with the buckle device provided beside the seat. So, put on your seat belt.

  The retractor configured as described above locks the pull-out of the seat belt from the take-up member at the time of a collision in which an impact is applied, and restrains the body of the occupant moving rapidly forward by the locked seat belt. Here, a pretensioner and a lock mechanism are usually provided in order to restrain the occupant's body more strongly, particularly at the time of collision prediction or sudden deceleration.

  The pretensioner removes the slack of the seat belt when the collision is predicted or the acceleration sensor detects that the vehicle is suddenly decelerated, and the restraint force by the seat belt is improved. The locking mechanism includes a locking member (locking base) that rotates together with the spool. And according to the detection signal of the acceleration sensor, the locking member (pawl) provided on the locking base is locked to the internal teeth (ratchet teeth) provided on the fixed side member (retractor frame etc.) of the vehicle, The rotation of the locking base and the spool in the pull-out direction is restricted (see, for example, Patent Document 1).

JP 2006-142984 A

  However, in the conventional seat belt retractor, the pretensioner operates more than necessary to restrain the occupant, which may cause discomfort.

  The present invention has been made in view of such circumstances, and an object of the present invention is to prevent passenger discomfort while ensuring safety by not operating a pretensioner according to the situation. To provide a belt retractor.

A seat belt retractor according to the present invention includes a detection unit that detects a seat belt retracting amount, a reception unit that receives collision prediction information output from the outside, and the reception unit in a seat belt retractor installed in a vehicle. If the collision prediction information is received by the detection unit, and the winding amount detected by the detection unit is determined not to fall within a predetermined range, the winding unit that winds up the seat belt and the reception unit And a prohibiting unit that prohibits winding of the seat belt by the winding unit when it is determined that the information is received and the winding amount detected by the detection unit is within a predetermined range. It is characterized by.

  The seat belt retractor according to the present invention includes a determining unit that determines the predetermined range based on a winding amount detected by the detection unit within a predetermined time after the seat belt is mounted.

  In the present invention, the detection unit detects the winding amount of the seat belt. The receiving unit receives collision prediction information output from the outside. Further, the winding unit winds up the seat belt when the receiving unit receives the collision prediction information. Here, when the winding amount detected by the detection unit is within a predetermined range, the prohibiting unit prohibits the winding of the seat belt by the winding unit.

  In the present invention, the determining means determines the predetermined range in the prohibiting means based on the winding amount detected from the detection unit within a predetermined time after the seat belt is mounted. The prohibiting unit prohibits the winding of the seat belt by the winding unit when the winding amount detected by the detecting unit is within the predetermined range determined by the determining unit.

  In the present invention, the receiving unit receives position information related to the position of the sheet. The determination unit determines whether or not the position information received by the receiving unit exceeds the sheet reference range stored in the storage unit. If it is determined that the sheet reference range is exceeded, the canceling unit cancels the winding prohibition by the prohibiting unit.

  In the present invention, when the winding amount detected by the detection unit is within a predetermined range, the prohibiting unit prohibits the winding of the seat belt by the winding unit. As a result, when the seat belt is present at an appropriate position, unnecessary winding can be omitted, and occupant discomfort can be reduced.

  In the present invention, the determining means determines the predetermined range in the prohibiting means based on the winding amount detected from the detection unit within a predetermined time after the seat belt is mounted. The prohibiting unit prohibits the winding of the seat belt by the winding unit when the winding amount detected by the detecting unit is within the predetermined range determined by the determining unit. Accordingly, since the prohibition of winding is executed according to the physique of the occupant, safety can be further improved.

  In the present invention, the determination unit determines whether or not the position information received by the reception unit exceeds the sheet reference range stored in the storage unit. If it is determined that the sheet reference range is exceeded, the canceling unit cancels the winding prohibition by the prohibiting unit. As a result, when the possibility of a secondary collision with the handle or the glass is high, the present invention has an excellent effect such that the winding prohibition can be canceled and the safety can be further improved.

It is a typical perspective view which shows the outline | summary of a seatbelt apparatus. It is a schematic diagram which shows the structure of a seatbelt retractor. It is a block diagram which shows the hardware constitutions of a control apparatus. It is a flowchart which shows the procedure of a reference | standard range determination process. It is a flowchart which shows the procedure of a reference | standard range determination process. It is a flowchart which shows the procedure of a winding process. It is explanatory drawing which shows the record layout of a coefficient table. 6 is a block diagram illustrating a hardware configuration of a control device according to Embodiment 2. FIG. It is explanatory drawing which shows the record layout of a sheet | seat reference | standard range file. It is a flowchart which shows the procedure of a cancellation | release process. It is a flowchart which shows the procedure of a cancellation | release process. 10 is a flowchart illustrating a procedure of reference range determination processing according to the second embodiment. 10 is a flowchart illustrating a procedure of reference range determination processing according to the second embodiment.

Embodiment 1
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic perspective view showing an outline of a seat belt device. The seat belt device 10 includes a seat belt (hereinafter referred to as a belt) 13 that restrains the body of the occupant 11 to the seat 12. The belt 13 includes a belt portion 13 a that restrains the upper body of the occupant 11 and a belt portion 13 b that restrains the waist of the occupant 11. One end of the belt portion 13b is fixed to the vehicle body portion at the lower part of the passenger compartment by an anchor plate 14. The belt portion 13 a is folded back by a through anchor 15 provided at a location near the shoulder of the occupant 11, and an end portion thereof is connected to a belt reel of the seat belt retractor 16. A tongue plate 17 is attached to the other common end of the belt 13. The tongue plate 17 is detachable from a buckle 18 fixed to the lower edge of the seat 12.

  FIG. 2 is a schematic diagram showing the configuration of the seat belt retractor. The seat belt retractor 16 includes a belt reel (spindle) 22 that is rotatably provided in the housing 21, and a motor 23 (winding unit) that rotationally drives the belt reel 22. The belt reel 22 is coupled to the end of the belt portion 13 a of the belt 13, and the belt portion 13 a is wound around the belt reel 22. The shaft 22 a of the belt reel 22 is connected to the drive shaft 23 a of the motor 23 via a power transmission mechanism (gear mechanism) 24. The belt reel 22 is rotationally driven by a motor 23 via a power transmission mechanism 24.

  When the motor 23 rotates in the forward direction, the belt 13 (belt portion 13a) is drawn and wound on the belt reel 22. When the motor 23 reverses, the belt reel 22 rotates to send out the belt 13 (belt portion 13a). By pulling the belt 13 by the rotation of the belt reel 22, the belt tension is increased and the restraint of the occupant 11 is increased. By feeding the belt 13 by the rotation of the belt reel 22, the belt tension is lowered and the restraint of the occupant 11 is eased. In this way, the holding control of the position and posture of the occupant 11 in the seat 12 is performed. In the present embodiment, an example in which the belt 13 is wound by the motor 23 at the time of collision prediction will be described, but the present invention is not limited to this. For example, the structure which winds up the belt 13 using the gunpowder which is not illustrated, or the combined use of the motor 23 and winding using the gunpowder may be used.

  A detection unit (hereinafter referred to as a sensor) 25 for detecting the winding amount of the belt 13 is attached to the inner wall of the housing 21. The winding amount may be detected by an angle sensor or the like that detects the rotation amount of the shaft 22a. The sensor 25 includes a sensor body 252 and an advance / retreat bar 251. One surface of the sensor body 252 is fixed to the inner wall of the housing 21 with screws or an adhesive. On the other surface side of the sensor main body 252, an advance / retreat rod 251 that advances and retreats in a direction intersecting the shaft 22 a of the belt reel 22 protrudes. The tip of the advance / retreat rod 251 is in contact with one surface of the belt 13. In accordance with the amount of winding of the belt 13, the advance / retreat rod 251 that contacts the one surface of the belt 13 at the tip moves forward and backward in the direction intersecting the shaft 22 a.

  That is, when the belt 13 is wound around the belt reel 22, the diameter of the belt 13 that is wound around the belt reel 22 is increased in cross-sectional view, so that the advance / retreat rod 251 enters the sensor body 252. On the other hand, as the belt 13 is pulled out, the diameter of the belt 13 wound around the belt reel 22 decreases in cross-sectional view, so that the advance / retreat rod 251 extends from the sensor body 252 toward the belt reel 22. The sensor body 252 outputs the advance / retreat position of the advance / retreat rod 251 to the control device 3 as the amount of winding of the belt 13. The control device 3 controls the motor 23 according to the winding amount output from the sensor 25.

  FIG. 3 is a block diagram illustrating a hardware configuration of the control device 3. The control device 3 includes a CPU (Central Processing Unit) 31, a RAM (Random Access Memory) 32, a CAN (Controller Area Network) communication unit 36, a clock unit 38, a motor drive control unit 231, a storage unit 35, and the like as control units. Including. The CPU 31 is connected to the hardware units of the control device 3 via the bus 37 and controls them, and executes various software functions according to the control program 35P stored in the storage unit 35. The storage unit 35 stores the above-described control program 35P, the reference range storage unit 351, the mounting range storage unit 352, the coefficient table 353, and the like.

  The CAN communication unit 36 as a receiving unit transmits / receives information to / from the distance sensor 42, the warning light 50, the load sensor 51, the vehicle speed sensor 41, the collision prediction unit 40, and the like according to the CAN protocol. In this embodiment, an example using CAN is described, but information may be transmitted and received by other protocols. The clock unit 38 outputs date / time information to the CPU 31. The motor drive control unit 231 controls forward rotation (winding of the belt 13) and reverse rotation (drawing of the belt 13) of the motor 23 according to an instruction from the CPU 31.

  The load sensor 51 is provided on the lower surface of the seat 12 and outputs an ON signal to the CAN communication unit 36 when a load based on the seating of the occupant 11 is detected. The mounting range storage unit 352 stores a winding amount range (hereinafter referred to as a mounting range) that is referred to when determining whether or not the occupant 11 is wearing the belt 13. For example, the mounting range storage unit 352 stores A1 or more and A2 or less. The sensor 25 detects the winding amount and outputs it to the CPU 31. In the above example, when the belt 13 is completely wound on the belt reel 22, the winding amount A <b> 3 that is an initial value is output to the CPU 31. Note that A3> A2> A1. When the occupant 11 pulls out the belt 13, the winding amount of A1 or more and A2 or less is output from the sensor 25, and the ON signal is output from the load sensor 51, the CPU 31 determines that the mounting of the belt 13 is completed, A light extinction signal is output to the warning lamp 50 via the CAN communication unit 36. In response to this, the warning light 50 is turned off. On the other hand, when an ON signal is output from the load sensor 51 and a winding amount of A1 to A2 is not output from the sensor 25, a lighting signal is output to the warning lamp 50. In response to this, the warning lamp 50 is lit to urge the user to wear the seat belt.

  The reference range storage unit 351 stores a range of the winding amount for the occupant 11 calculated by the CPU 31. After determining that the belt 13 is attached, the CPU 31 refers to the date and time information output from the clock unit 38 and calculates the average value of the winding amount output from the sensor 25 within a predetermined time (for example, within 5 seconds). . The CPU 31 stores a winding amount of ± 5% of the calculated average value in the reference range storage unit 351 as an upper limit value and a lower limit value of the reference range. For example, the upper limit is a2, the lower limit is a1, and the reference range is a1 or more and a2 or less. Note that A1 ≦ a1 <a2 ≦ A2. The reference range setting example of ± 5% is merely an example, and an appropriate value may be adopted according to the vehicle body strength and the like. Further, the predetermined time is stored in advance in the storage unit 35 and is appropriately read according to an instruction from the CPU 31.

  The distance sensor 42 is, for example, a millimeter wave radar, an ultrasonic sensor, or a plurality of CCD (charge-coupled device) cameras, and is mounted in front of the vehicle. The distance sensor 42 calculates a distance to an obstacle existing ahead, and outputs the distance to the collision prediction unit 40 and the like. In addition, although the distance sensor 42 demonstrates the example which detects the distance to the obstruction which exists ahead, you may detect the distance to the obstruction which exists sideways or back.

  The vehicle speed sensor 41 detects the vehicle speed and outputs the detected vehicle speed to the collision prediction unit 40 and the like. The collision prediction unit 40 that predicts a vehicle collision outputs collision prediction information to the control device 3 via the CAN communication unit 36 based on the distance output from the distance sensor 42 and the vehicle speed output from the vehicle speed sensor 41. To do. As a collision prediction method, for example, the relative speed is calculated from the temporal change in the distance output from the distance sensor 42. The collision prediction unit 40 calculates the time until the collision based on the calculated relative speed and the distance to the obstacle. When the calculated time is equal to or less than the predetermined time stored in advance, the collision prediction unit 40 outputs collision prediction information indicating that the possibility of collision is high to the control device 3 via the CAN communication unit 36.

  When the collision prediction information is output from the collision prediction unit 40, the CPU 31 outputs a forward rotation command (hereinafter referred to as a winding command) of the belt 13 to the motor drive control unit 231. When receiving the winding command, the motor drive control unit 231 drives the motor 23 in the direction in which the belt 13 is wound by a predetermined amount. On the other hand, when the winding amount output from the sensor 25 is within the reference range stored in the reference range storage unit 351, the CPU 31 performs processing for prohibiting the output of the winding command described above. Although the winding of the belt 13 is prohibited, the lock mechanism is activated and the occupant 11 is restrained by the belt 13. In recent years, the interior space has high rigidity due to the presence of a highly rigid frame. Therefore, when sufficient space is secured between the occupant 11 and the steering wheel or dashboard, forcible winding is prohibited because the possibility of a secondary collision is low.

  Software processing according to the present embodiment in the above hardware configuration will be described using a flowchart. 4 and 5 are flowcharts showing the procedure of the reference range determination process. The CPU 31 determines whether or not an on signal is output from the load sensor 51 (step S41). When the CPU 31 determines that the ON signal is not output (NO in step S41), the above process is repeated. On the other hand, if the CPU 31 determines that the ON signal is output from the load sensor 51 (YES in step S41), the CPU 31 outputs a lighting signal to the warning lamp 50 via the CAN communication unit 36 (step S42). The CPU 31 reads the mounting range stored in advance in the mounting range storage unit 352 (step S43).

  The CPU 31 refers to the winding amount output from the sensor 25, and determines whether or not the winding amount output from the sensor is within the read mounting range (step S44). If the CPU 31 determines that it is not within the mounting range (NO in step S44), it determines that the belt 13 is not yet mounted, and repeats the process of step S44 again. On the other hand, when the CPU 31 determines that the winding amount is within the mounting range (YES in step S44), the CPU 31 determines that the belt 13 is mounted and outputs a turn-off signal to the warning lamp 50 (step S45). This eliminates the need to provide a buckle switch in the buckle 18 for detecting the connection with the tongue plate 17.

  Subsequently, the CPU 31 refers to the date and time information output from the clock unit 38 after the belt 13 is mounted, and determines whether or not a predetermined time stored in the storage unit 35 has elapsed (step S46). If the CPU 31 determines that the predetermined time has not elapsed (NO in step S46), it repeatedly executes the process of step S46. On the other hand, if the CPU 31 determines that the predetermined time has elapsed (YES in step S46), the winding amount output from the sensor 25 is stored in the RAM 32 for a predetermined time (step S47). For example, sampling may be performed every 1/10 seconds, and the winding amount for 5 seconds may be sequentially stored in the RAM 32. The CPU 31 calculates the average value of the winding amount by dividing the total value of the winding amount stored in the RAM 32 by the sampling number (step S48).

  The CPU 31 calculates the variance value by dividing the sum of the squares of the difference between the calculated average value and the winding amount at each time stored in the RAM 32 by the sampling number (step S49). The CPU 31 reads a threshold value stored in advance from the storage unit 35 (step S51). The CPU 31 determines whether or not the calculated variance value is equal to or less than a threshold value (step S52). If the CPU 31 determines that the variance value is not less than or equal to the threshold value (NO in step S52), it determines that the position of the seat 12 is being adjusted or the occupant 11 is not sitting properly on the seat 12, and the information in the RAM 32 is erased. (Step S53). Thereafter, the CPU 31 returns the process to step S47 again.

  When the CPU 31 determines that the variance value is equal to or less than the threshold value (YES in step S52), the CPU 31 determines that the occupant 11 is seated at the correct driving position on the seat 12, and calculates the reference range based on the average value calculated in step S48. (Step S54). Specifically, the CPU 31 reads the lower limit coefficient (for example, 0.95) and the upper limit coefficient (for example, 1.05) from the storage unit 35, and calculates the reference range by multiplying these coefficients by the average value. The CPU 31 stores the calculated reference range in the reference range storage unit 351 (step S55).

  The CPU 31 refers to the winding amount output from the sensor 25, and determines whether or not the winding amount output from the sensor is within the read mounting range (step S56). If the CPU 31 determines that the belt is within the mounting range (YES in step S56), the CPU 31 determines that the belt 13 is mounted and repeats the process of step S56 again. On the other hand, if the CPU 31 determines that the winding amount is not within the attachment range (NO in step S56), it determines that the belt 13 has been removed, and outputs a turn-off signal to the warning lamp 50 (step S57). The CPU 31 erases the stored contents of the reference range storage unit 351 (step S58).

  FIG. 6 is a flowchart showing the procedure of the winding process. CPU31 receives the vehicle speed output from the vehicle speed sensor 41 (step S61). Information input to the control device 3 is received by the CAN communication unit 36, and the CAN communication unit 36 outputs the received information to the CPU 31. The CPU 31 may change the reference range according to the speed based on a coefficient table described below.

  FIG. 7 is an explanatory diagram showing a record layout of the coefficient table 353. The coefficient table 353 includes a speed field, a lower limit coefficient field, and an upper limit coefficient field. A speed range is stored in the speed field. The lower limit coefficient field stores a lower limit coefficient to be multiplied by the average value in association with the speed range. The upper limit coefficient field stores an upper limit coefficient to be multiplied by the average value in association with the speed range. The lower limit coefficient field is stored so that the lower limit coefficient increases as the speed increases. On the other hand, the upper limit coefficient field is stored such that the upper limit coefficient decreases as the speed increases. This is because when the speed increases, the reference range is narrowed and safety is given priority over comfort.

  In the same velocity body, the lower limit coefficient and the upper limit coefficient are set such that the difference (or absolute value) between the reference coefficient 1 and the lower limit coefficient is smaller than the difference (or absolute value) between the upper limit coefficient and the reference coefficient 1. Is remembered. This is because when the winding amount is small, in other words, when the winding is insufficient, it is necessary to secure the safety by narrowing the reference range. For example, when the speed is less than 30 km and the speed is low, the lower limit coefficient is stored as 0.93 (93%), and the upper limit coefficient is stored as 1.10 (110%). In this case, it can be understood that the lower limit coefficient side is set to have a smaller difference from the numerical value 1 than the upper limit coefficient. When the speed is 80 km or more, such as when driving on a highway, the lower limit coefficient is 0.97 (97%) and the upper limit coefficient is 1.07 (107%) in order to narrow this reference range and more precisely control the lower limit side. Is remembered. Even in this case, the difference from the numerical value 1 on the lower limit coefficient side is set smaller than the upper limit coefficient.

  CPU31 reads the coefficient corresponding to the vehicle speed received by step S61 from the coefficient table 353 (step S62). The CPU 31 calculates the reference range by multiplying the average value calculated in step S48 by the read coefficient (lower limit coefficient and upper limit coefficient) (step S63). The CPU 31 stores the calculated reference range in the reference range storage unit 351 (step S64). Of course, as shown in FIGS. 4 and 5, the reference range may be constant regardless of the speed. In addition, the layout of data stored in the coefficient table 353, the reference range storage unit 351, the mounting range storage unit 352, and the like is merely an example, and an appropriate data holding method may be employed depending on the design.

  CPU31 judges whether collision prediction information was received from collision prediction part 40 (Step S65). When CPU 31 has not received the collision prediction information (NO in step S65), the process returns to step S61. On the other hand, when the CPU 31 determines that the collision prediction information has been received (YES in step S65), the CPU 31 reads the reference range stored in the reference range storage unit 351 (step S66). The CPU 31 determines whether or not the winding amount output from the sensor 25 is within the reference range (step S67).

  If the CPU 31 determines that it is not within the reference range (NO in step S67), it outputs a winding command to the motor drive controller 231 to execute the pretensioner (step S68). When the motor drive control unit 231 receives a winding command, the motor driving control unit 231 performs control for winding the motor 23 in a winding direction of the belt 13 by a predetermined amount. On the other hand, if the CPU 31 determines that it is within the reference range (YES in step S67), it outputs a winding command prohibition command to the motor drive control unit 231 to deactivate the pretensioner (step S69). In this case, the motor drive control unit 231 does not drive the motor 23 even if the collision prediction information is received from the collision prediction unit 40. As a result, when the collision is predicted and the occupant 11 is seated due to falling asleep or an unnatural posture, the occupant can be restrained by winding the belt 13. On the other hand, when the take-up amount falls within the reference range and is correctly seated, the operation of the pretensioner can be prohibited and occupant discomfort can be prevented.

Embodiment 2
The second embodiment relates to a process for canceling the winding prohibition according to the position of the sheet 12. FIG. 8 is a block diagram illustrating a hardware configuration of the control device 3 according to the second embodiment. In addition to the configuration of the first embodiment, a sheet reference range file 354, an electric seat control unit 52, and an input unit 33 are provided. The input unit 33 configured by a plurality of operation buttons and the like is used for selecting an installation location of the seat belt retractor 16. The installation locations are a driver's seat, a passenger seat, a rear seat behind the driver seat, a rear seat behind the passenger seat, and the like. When the seat belt retractor 16 is attached, an installation location is input from the input unit 33. The information on the input installation location is output to the CPU 31, and the installation location is stored in the storage unit 35. In the present embodiment, a mode in which the installation location can be selected by the input unit 33 will be described, but the present invention is not limited to this. Of course, the seat belt retractor 16 may be manufactured in advance so as to be attached to a specific position, such as for the driver's seat or the passenger's seat.

  FIG. 9 is an explanatory diagram showing a record layout of the sheet reference range file 354. The seat reference range file 354 includes an installation location field, a front and rear reference range field, and an inclination reference range field. The sheet reference range file 354 stores a sheet reference range (front and rear reference range and inclination reference range) in association with the installation location. Information regarding the installation location of the seat 12 is stored in the installation location field. In this example, a driver seat, a passenger seat, and a rear seat are stored as installation locations. In the front / rear reference range field, the front / rear reference range of the seat 12 is stored in association with the installation location. Similarly, an inclination reference range is stored in the inclination reference range field in association with the installation location.

  The electric seat controller 52 electrically changes and controls the position of the seat 12, that is, the front and rear positions of the seating surface and the inclination angle of the backrest. The electric seat control unit 52 includes a front / rear adjustment unit 521 for adjusting the front / rear position of the seat surface, and an inclination angle adjustment unit 522 for adjusting the inclination angle of the backrest. The front-rear adjustment unit 521 and the inclination angle adjustment unit 522 are provided, for example, on the side surface of the seat surface of the seat 12 or the door side surface. The front / rear position and the tilt angle input from the front / rear adjustment unit 521 are output to the CPU 31 via the CAN communication unit 36.

  In the example of FIG. 9, when the installation location is the driver's seat, x1 or more is stored as the front-rear reference range. Note that an upper limit may be provided and x1 or more and x1 'or less. In the present embodiment, the front-rear reference range has a position where the seat surface of the seat 12 is closest to the windshield (not shown) side as the origin. When the installation location is the passenger seat, x2 or more is stored as the front-rear reference range. These x1 or more and x2 or more may be set in a range in which a secondary collision can be prevented even at the time of a collision. For example, when the front-rear reference position on the driver's seat side is smaller than x1 (from the front), the front-rear reference range is exceeded, so the winding prohibition command is canceled. When the installation location is the rear seat, x3 or less is stored as the front-rear reference range. In the rear seat, a front / rear reference range x3 or less in which the occupant can avoid a secondary collision on the back surface of the front seat 12 or the front seat 12 is stored. For example, when the front / rear reference position on the driver's seat side is larger than x3 (from the rear), the front / rear reference range is exceeded, and therefore the winding prohibition command is canceled.

  The inclination reference range has the origin of the angle of the backrest when the backrest of the seat 12 is inclined most toward the windshield. When the installation location is the driver's seat, y1 or more is stored as the tilt reference range. When the installation location is the passenger seat, y2 or more is stored as the tilt reference range. These y1 and y2 may be set at positions where secondary collisions can be prevented even during a collision. When the installation location is the rear seat, y3 or less is stored as the tilt reference range. In the rear seat, an inclination reference range y3 or less in which the occupant can avoid a secondary collision on the back of the front seat 12 or the passenger seat 12 is stored. In the present embodiment, as the seat reference range, two front and rear reference ranges and an inclination reference range will be described as examples, but either one may be used.

  10 and 11 are flowcharts showing the procedure of the release process. CPU31 receives the information of an installation place from the input part 33 (step S101). The CPU 31 stores the received installation location information in the storage unit 35 (step S102). The CPU 31 receives the front / rear position input from the front / rear adjustment unit 521 and the tilt position input from the tilt angle adjustment unit 522 (step S103). CPU31 performs the process of step S61-S66 described in FIG. 6 of Embodiment 1, and judges whether the winding amount output from the sensor 25 is less than a reference range (step S104).

  If the CPU 31 determines that it is not within the reference range (NO in step S104), it outputs a winding command to the motor drive controller 231 to execute the pretensioner (step S105). When the motor drive control unit 231 receives a winding command, the motor driving control unit 231 performs control for winding the motor 23 in a winding direction of the belt 13 by a predetermined amount. On the other hand, when the CPU 31 determines that it is within the reference range (YES in step S104), it refers to the storage unit 35 and determines whether or not the installation location is the rear seat (step S106). This processing is omitted when the installation location is determined from the beginning. When the CPU 31 determines that the installation location is not the rear seat (NO in step S106), the CPU 31 determines whether or not the installation location is a driver seat (step S107).

  If the CPU 31 determines that the installation location is the driver's seat (YES in step S107), the CPU 31 reads the front / rear reference range and the tilt reference range corresponding to the driver's seat with reference to the seat reference range file 354 (step S108). On the other hand, if the CPU 31 determines that the installation location is not the driver's seat (NO in step S107), the CPU 31 determines that the installation location is the passenger seat, refers to the seat reference range file 354, and the front and rear reference ranges corresponding to the passenger seat and The inclination reference range is read (step S109). After the processing of steps S108 and S109, the CPU 31 determines whether or not the front and rear position received in step S103 exceeds the read front and rear reference range, or whether or not the received tilt position exceeds the read tilt reference range. (Step S1010).

  If the CPU 31 determines that the front / rear reference range or the tilt reference range is not exceeded (NO in step S1010), the possibility of a secondary collision is low, and the motor drive control unit 231 is instructed to deactivate the pretensioner. A winding command prohibition command is output (step S1011). Thereby, unnecessary winding is prevented when the winding amount is within the reference range. On the other hand, when CPU 31 determines that it exceeds the front-rear reference range or exceeds the tilt reference range (in this example, on the driver's seat side, it is smaller than x1 or smaller than y1) (YES in step S1010) Since there is a risk of secondary collision, the prohibition of the winding command is canceled and the winding command is output to the motor drive control unit 231 to execute the pretensioner (step S1012). When the motor drive control unit 231 receives a winding command, the motor driving control unit 231 performs control for winding the motor 23 in a winding direction of the belt 13 by a predetermined amount. As a result, in the driver's seat or passenger's seat, even if the winding amount is within the reference range, the distance between the subject of the secondary collision such as the steering wheel, dashboard or windshield and the occupant cannot be secured sufficiently The safety can be further improved by releasing the operation prohibition of the pretensioner and operating the pretensioner.

  If it is determined in step S106 that the installation location is the rear seat (YES in step S106), the front / rear reference range and the tilt reference range corresponding to the rear seat are read (step S110). The CPU 31 determines whether or not the front and rear position received in step S103 exceeds the read front and rear reference range, or whether or not the received tilt position exceeds the read tilt reference range (step S111). The front-rear position and the tilt position received in step S103 are the front-rear position and the tilt position of the driver seat when the determination in step S111 is the rear seat behind the driver seat. Further, the front-rear position and the tilt position received in step S103 are the front-rear position and the tilt position of the passenger seat when the determination in step S111 is the rear seat behind the passenger seat. That is, the front / rear position and the inclined position of the front driver's seat or front passenger seat installed in front of the rear seat to be determined.

  When the CPU 31 determines that the front / rear reference range or the tilt reference range is not exceeded (NO in step S111), the CPU 31 outputs a winding command prohibition command to the motor drive control unit 231 to deactivate the pretensioner ( Step S112). Thereby, unnecessary winding is prevented when the winding amount is within the reference range. On the other hand, when the CPU 31 determines that it exceeds the front / rear reference range or exceeds the tilt reference range (in this example, the rear seat is larger than x3 or larger than y3) (YES in step S111), In order to execute the pretensioner, the prohibition of the winding command is canceled and the winding command is output to the motor drive control unit 231 (step S113). When the motor drive control unit 231 receives a winding command, the motor driving control unit 231 performs control for winding the motor 23 in a winding direction of the belt 13 by a predetermined amount. As a result, even if the winding amount is within the reference range, if the seat 12 on the driver's seat or passenger's side is moving backward, or if the inclination angle is large, the seat on the driver's seat or passenger's side 12 When the distance between the rear surface and the occupant cannot be sufficiently secured, the safety can be further improved by releasing the operation prohibition of the pretensioner and operating it.

  Further, as described below, the reference range may be changed according to the front-rear position or the tilt position of the seat 12. The storage unit 35 stores auxiliary coefficients for correcting the lower limit coefficient and the upper limit coefficient shown in FIG. For example, as the auxiliary coefficient, a lower limit auxiliary coefficient larger than 1 (for example, 1.02) for increasing the lower limit coefficient is stored, and an upper limit auxiliary coefficient (for example, 0.99) for decreasing the upper limit coefficient is stored. The

  12 and 13 are flowcharts showing the procedure of the reference range determination process according to the second embodiment. CPU31 receives the vehicle speed output from the vehicle speed sensor 41 (step S121). CPU31 reads the coefficient corresponding to the vehicle speed received by step S121 from the coefficient table 353 (step S122). The CPU 31 receives the front / rear position input from the front / rear adjustment unit 521 and the tilt position input from the tilt angle adjustment unit 522 (step S123). The CPU 31 refers to the storage unit 35 and determines whether or not the installation location is the rear seat (step S124). If the CPU 31 determines that the installation location is not the rear seat (NO in step S124), the CPU 31 determines whether or not the installation location is a driver seat (step S125).

  When the CPU 31 determines that the installation location is the driver's seat (YES in step S125), the CPU 31 reads the front / rear reference range and the tilt reference range corresponding to the driver's seat with reference to the seat reference range file 354 (step S126). On the other hand, if the CPU 31 determines that the installation location is not the driver's seat (NO in step S125), the CPU 31 determines that the installation location is the front passenger seat, refers to the seat reference range file 354, and the front / rear reference range corresponding to the front passenger seat and The inclination reference range is read (step S127). After the processes of steps S126 and S127, the CPU 31 determines whether or not the front and rear position received in step S123 exceeds the read front and rear reference range, or whether or not the received tilt position exceeds the read tilt reference range. Judgment is made (step S128).

  When the CPU 31 determines that it does not exceed the front / rear reference range or the tilt reference range (NO in step S128), the CPU 31 calculates the reference range by multiplying the average value calculated in step S48 by the coefficient read in step S122 (step S132). ). On the other hand, if the CPU 31 determines that it exceeds the front / rear reference range or exceeds the tilt reference range (YES in step S128), the auxiliary coefficient is read from the storage unit 35, and the average value calculated in step S48 is read in step S122. A reference range is calculated by multiplying the coefficient and the auxiliary coefficient (step S133).

  If it is determined in step S124 that the installation location is the rear seat (YES in step S124), the front / rear reference range and the tilt reference range corresponding to the rear seat are read (step S129). The CPU 31 determines whether or not the front / rear position received in step S123 exceeds the read front / rear reference range, or whether the accepted tilt position exceeds the read tilt reference range (step S131). The front-rear position and the tilt position received in step S123 are the front-rear position and the tilt position of the driver seat when the determination in step S131 is the rear seat behind the driver seat. Further, the front-rear position and the tilt position received in step S123 are the front-rear position and the tilt position of the passenger seat when the determination in step S131 is the rear seat behind the passenger seat.

  When the CPU 31 determines that it does not exceed the front / rear reference range or the tilt reference range (NO in step S131), the CPU 31 calculates the reference range by multiplying the average value calculated in step S48 by the coefficient read in step S122 (step S132). ). On the other hand, if the CPU 31 determines that it exceeds the front / rear reference range or exceeds the tilt reference range (YES in step S131), the auxiliary coefficient is read from the storage unit 35, and the average value calculated in step S48 is read in step S122. A reference range is calculated by multiplying the coefficient and the auxiliary coefficient (step S133).

  Finally, the CPU 31 stores the calculated reference range in the reference range storage unit (step S134). Since the subsequent steps are the same as those in step S65 and subsequent steps shown in the first embodiment, detailed description thereof is omitted. Thereby, when the seat position is close to the target of the secondary collision, it is possible to reduce the range in which the winding prohibition control is performed, and it is possible to further improve the safety.

  The second embodiment is configured as described above, and the other configurations and operations are the same as those of the first embodiment. Therefore, corresponding parts are denoted by the same reference numerals, and detailed description thereof is omitted.

DESCRIPTION OF SYMBOLS 10 Seat belt apparatus 12 Seat 13 Belt 14 Anchor plate 18 Buckle 16 Seat belt retractor 22 Belt reel 21 Housing 23 Motor 22a Shaft 23a Drive shaft 25 Sensor 40 Collision prediction part 41 Vehicle speed sensor 42 Distance sensor 50 Warning light 51 Load sensor 52 Electric seat Control unit 521 Front / rear adjustment unit 522 Inclination angle adjustment unit 3 Control device 31 CPU
32 RAM
33 Input unit 36 CAN communication unit 38 Clock unit 231 Motor drive control unit 35 Storage unit 35P Control program 351 Reference range storage unit 352 Attachment range storage unit 353 Coefficient table 354 Sheet reference range file

Claims (2)

In the seat belt retractor installed in the vehicle,
A detection unit for detecting the amount of winding of the seat belt;
A receiving unit that receives collision prediction information output from the outside;
A winding unit that winds up the seat belt when it is determined that the collision prediction information has been received by the receiving unit , and the winding amount detected by the detection unit is not within a predetermined range ;
When it is determined that the collision prediction information has been received by the receiving unit and the winding amount detected by the detecting unit is within a predetermined range, the seat belt is prohibited from being wound by the winding unit. A seat belt retractor comprising: a prohibiting means. The seat belt retractor according to claim 1, further comprising: a determining unit that determines the predetermined range based on a winding amount detected by the detection unit within a predetermined time after the seat belt is mounted.

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