JP2008044465A - Vehicle seat belt device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle seat belt device capable of maintaining occupant holding control by preventing functional deterioration in the occupant holding control by a seat belt even if fault occurs in a state detecting system assessing the driving amount of a motor executing the pulling-in/sending-out of the belt. <P>SOLUTION: This vehicle seat belt device 10 is provided with an electric type pretensioner composed of a belt reel 22 winding the belt 13 and the motor 23 driving this belt reel and pulling in the belt. The seat belt device is provided with a winding position detecting part 25, a motor current sensor 29, and a control device 26 (63) controlling the drive of the motor by controlling a current-carrying amount to the motor. The control device is provided with a first control mode controlling the current-carrying amount based on the detection value of the winding position detecting part, and a second control mode controlling the current-carrying amount based on the detection value of the motor current sensor. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle seat belt device, and more particularly to a vehicle seat belt device that maintains its function by providing an alternative means when a device state detection system fails.

  With regard to seat belt devices equipped to protect occupants in vehicle seats, in recent years, a technology that suppresses posture changes by restraining occupants with belts in an emergency or when running conditions are unstable has been put into practical use. Has been.

As a prior art disclosing a seat belt device, there is a system described in Patent Document 1 below. Patent Document 1 discloses an occupant restraint protection system that performs control in consideration of the situation of the host vehicle, and more efficiently performs restraint protection for the occupant.
JP 2004-291967 A

  According to a vehicle seat belt device, a motor drive amount is controlled by controlling an energization amount to a motor that normally performs a rotation operation of a retractor that pulls in and out a belt, and a predetermined posture with respect to an occupant is determined. Give hold restraint. For this reason, in the vehicle seat belt device, a motor current sensor that detects the amount of power supplied from the power source to the motor is provided, and the motor current amount detected by the motor current sensor is provided to a control device that executes motor drive amount control. Is done.

  When the motor current sensor fails in the above, the detected value of the motor energization amount becomes inaccurate, and the evaluation of the motor drive amount becomes inaccurate. When the motor drive amount is underestimated, the motor energization amount becomes larger and excessively restricts the occupant. When the motor drive amount is overestimated, the occupant's restraining force is insufficient. .

  In view of the above problems, an object of the present invention is to provide an occupant holding control by a seat belt even if a failure occurs in a state detection system that evaluates a motor driving amount with respect to a driving control of a motor that causes a belt reel to be pulled in and out. It is an object of the present invention to provide a seat belt device for a vehicle that can prevent a decrease in the function of the vehicle and maintain occupant holding control.

  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 an electric pretensioner including a belt reel that winds the belt, and a motor that drives the belt reel to retract the belt. A winding position detecting means for detecting the winding position of the belt reel, a motor current detecting means for detecting the energization amount to the motor, and a control means for controlling the driving of the motor by controlling the energization amount to the motor. . The control means includes a first control mode (rotation angle control) for controlling the energization amount based on the detection value of the winding position detection means, and a second control for controlling the energization amount based on the detection value of the motor current detection means. A control mode (current control) is provided.

  In the above-described vehicle seat belt device, the state detection system for evaluating the motor drive amount with respect to the drive control of the motor that causes the belt reel to pull in / send out the belt includes two winding position detection means and motor current detection means. A system is provided so that even if one of the state detection systems fails, the remaining state detection system can be used. The control means has, as the motor control mode, a first control mode using the winding position detection means and a second control mode using the motor current detection means, and either one or both depending on the situation. The control mode is used. Since an alternative control means is provided for the state detection system, even if a failure occurs in any of the state detection systems, the remaining state detection system is used to prevent a decrease in the function of occupant holding control by the seat belt, It is possible to maintain occupant holding control.

  The seatbelt device for the second vehicle (corresponding to claim 2) preferably includes a first failure detection means for detecting a failure of the winding position detection means in the above configuration, and the first failure detection means. When the failure of the winding position detecting means is detected, the first control mode is invalidated.

  The seatbelt apparatus for a third vehicle (corresponding to claim 3) preferably includes a second failure detection means for detecting a failure of the motor current detection means in the above configuration, wherein the second failure detection means is The second control mode is invalidated when a failure of the motor current detecting means is detected.

  According to the present invention, the state detection system for evaluating the motor drive amount is used as the winding position detection means and the motor current detection for the drive control of the motor that causes the belt reel to retract and send the belt in the seat belt device of the vehicle. The control means has a first control mode using the winding position detection means and a second control mode using the motor current detection means, and an alternative control means is provided for the state detection system. As a result, even if a failure occurs in one of the state detection systems, the remaining state detection system can be used to prevent a reduction in the function of the occupant holding control by the seat belt, and maintain the occupant holding control. be able to.

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

  FIG. 1 shows, as an example, a state in which a seat belt device is installed in a driver's seat, FIG. 2 shows a configuration of a retractor for a seat belt, and FIG. 3 shows an overall configuration of a control system for a vehicle seat belt device.

  In FIG. 1, a seat belt device 10 includes a belt (webbing) 13 that restrains the body of an occupant 11 to a 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 near a shoulder of the occupant 11, and an end portion thereof is connected to a belt reel of the retractor 16. A tongue plate 17 is attached to the other common end of the belt 13. The tongue plate 17 is detachably attached to a buckle 18 fixed to the lower edge of the seat 12. The buckle 18 is provided with a buckle switch 19 that detects the connection of the tongue plate 17.

  FIG. 2 shows a main configuration of the seat belt retractor 16. The retractor 16 includes a belt reel (spindle) 22 that is rotatably provided in the housing 21 and a motor 23 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. The retractor 16 includes a winding position detector 25 connected to the shaft 22a of the belt reel 22.

  When the motor 23 rotates forward in the above, 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 position and posture holding control of the occupant 11 in the seat 12 is performed.

  The winding position detection unit 25 is preferably configured using a rotation angle sensor. For example, a magnetic sensor formed by combining a magnetic disk and two Hall ICs is used as the rotation angle sensor. The minimum resolution angle of the rotation angle sensor is, for example, 4 °, and is about 1.3 to 1.6 mm when converted into the belt length. As the winding position detection unit 25, a belt length sensor can be used instead of the rotation angle sensor.

  According to the winding position detection unit 25, it is possible to detect the belt winding position by the belt reel 22 by detecting the rotation angle of the belt reel 22 with a built-in rotation angle sensor. A detection signal output from the winding position detection unit 25 is input to the control device 26. The rotation operation of the belt reel 22 in the retractor 16 is controlled by the control device 26. The control device 26 controls the belt winding operation by the retractor 16 by controlling the energization amount of the drive current I1 supplied from the power source 27 to the motor 23 to a predetermined value by the energization amount adjustment unit 28. The retractor 16 controlled by the control device 26 is configured as an electric pretensioner for maintaining the position and posture of the occupant 11.

  In addition, a motor current sensor 29 is arranged in an energization route for supplying current to the motor 23 from the power supply 27 via the energization amount adjusting unit 28. The motor energization amount I 1 detected by the motor current sensor 29 is input to the control device 26. The control device 26 determines whether or not the motor energization amount is a predetermined value based on the detection signal of the motor energization amount I1 supplied from the motor current sensor 29.

  In the above configuration, the control device 26 controls the operation of the motor 23 in the first control mode for controlling the energization amount to the motor 23 based on the detection value of the winding position detection unit 25, and the motor current sensor 29. A second control mode for controlling the energization amount to the motor 23 based on the detected value is provided. This point will be described in detail later.

  The seat belt device 10 and the retractor 16 included therein are devices on the driver's seat side, but the same seat belt device and retractor are also provided on the passenger seat side. In the following, the “R side” is the driver seat side, and the “L side” is the passenger seat side.

  With reference to the block diagram of FIG. 3, the control system of the seat belt device 10 and the like will be described from the viewpoint of hardware.

  In FIG. 3, the control device 26 described above is composed of a CPU. A block 30 including the control device 26 represents an electric pretensioner unit for holding the position / posture of the occupant 11 by a seat belt. The block 30 includes a power source 31, an in-vehicle network (CAN) communication unit 32, a rotation angle interface (rotation angle I / F) unit 33, and a communication unit 34 on the input side of the control device (CPU) 26, and on the output side thereof. An R-side motor drive control unit 35, an L-side motor drive control unit 36, and a recording unit 37 are provided. The recording unit 37 is a memory that stores data and a control program.

  Further, on the input side of the block 30, a block showing the above retractor 16 is provided as an example of a seat belt retractor. The retractor 16 includes a rotation angle interface (rotation angle I / F) unit 41 for transmitting a detection signal output from the winding position detection unit 25 described above to the control device 26. The rotation angle interface unit 41 is connected to the rotation angle interface unit 33 in the block 30 and sends a detection signal to the rotation angle interface unit 33. The retractor 16 is provided for each of the driver's seat side and the passenger seat side.

  On the input side of the block 30, for example, an ACC (Adaptive Cruise Control) unit (control unit such as an obstacle detection device) 42, a VSA (Vehicle Stability Assist) unit (vehicle behavior stabilization control unit) 43, FI / AT A (Fuel Injection / Automatic Transmission) unit 44, an SRS (Supplement Restraint System) unit (auxiliary restraint device unit) 45, and the like are provided. These input side elements include a vehicle running state detection unit such as a vehicle speed sensor. The ACC unit 42, the VSA unit 43, the FI / AT unit 44, and the like supply their output signals to the in-vehicle network communication unit 32 through the in-vehicle network 46. The SRS unit 45 includes an SRS control unit 45a that receives signals from the R-side buckle 47R and the L-side buckle 47L, and a communication unit 45b. Here, the R-side buckle 47R corresponds to the buckle 17 on the driver's seat side, and the L-side buckle 47L is a buckle of a seat belt device equipped on the passenger seat side. Each signal output from the R side buckle 47R and the L side buckle 47L is a detection signal of a built-in buckle switch. When receiving a signal from the R side buckle 47R or the L side buckle 47L, the SRS control unit 45a transmits the signal to the communication unit 32 of the block 30 via the communication unit 45b. Further, the SRS unit 45 supplies a warning signal to the warning lamp 48 when the seat belt is not normally used when the vehicle is traveling.

  An R-side motor 51 and an L-side motor 52 are provided on the output side of the block 30. The R-side motor 51 is a driving motor for the seat belt device 10 on the driver's seat side, and is disposed corresponding to the R-side motor drive control unit 35. The R-side motor 51 corresponds to the motor 23 described above. The R-side motor drive control unit 35 controls the energization amount from the power source (+ V) 27 based on a control command signal from the control device 26 and supplies a drive current to the R-side motor 51. The R-side motor drive control unit 35 includes the energization amount adjustment unit 28 as described with reference to FIG. The block 53 is a grounding part.

  The L-side motor 52 is a driving motor for the seat belt device 10 in the passenger seat, and is disposed corresponding to the L-side motor drive control unit 36. The L-side motor drive control unit 36 controls the energization amount from the power source (+ V) 54 based on a control command signal from the control device 26 and supplies a drive current to the L-side motor 52. The block 55 is a grounding part. The grounding portions 53 and 55 are grounding terminals that form part of the vehicle body.

  In the above description, the motor current sensor 29 is disposed in the motor current supply path of the R-side motor 51, and the detection signal is supplied to the control device 26 via the R-side motor drive control unit 35. Similarly, a motor current sensor 29 is arranged for the L-side motor 52, and the detection signal is supplied to the control device 26 via the L-side motor drive control unit 36.

  In the above configuration, the control device 26 uses the control program stored in the recording unit 37 to control the energization amount to the motor 23 based on the detection value of the winding position detection unit 25 as described above. The mode and the second control mode for controlling the energization amount to the motor 23 based on the detection value of the motor current sensor 29 are performed. The first control mode and the second control mode are preferably implemented selectively.

  The first control mode uses the winding position detection unit 25 and is a rotation angle control mode using the rotation angle of the belt reel 22. The second control mode uses the motor current sensor 29 and is a current control mode using the motor energization amount.

  In the first control mode (rotation angle control), as described above, the rotation angle of the belt reel 22 is set to the target rotation angle based on the winding position (rotation angle) detected by the winding position detection unit 25. The motor energization amount is controlled so that The first control mode is control for the purpose of ensuring the position of the belt with respect to the occupant 11.

  In the second control mode (current control), the motor 23 is energized so that a predetermined belt tension is generated in the rotating state of the belt reel 22 based on the motor energization amount detected from the motor current sensor 29. The amount is controlled to be the target current value. The second control mode is control for the purpose of securing a binding force acting on the occupant 11.

  FIG. 4 is a functional block diagram conceptually showing the basic configuration of the control system of the seatbelt device 10 according to the present embodiment. This control system includes a winding position detection unit 25, a motor current sensor 29, a vehicle travel state detection unit 61, a vehicle travel state determination unit 62, a seat belt device control unit 63, and a belt drive unit 64. It is composed of

  The vehicle running state detection unit 61 includes a plurality of various sensors such as a vehicle body longitudinal acceleration sensor, a vehicle body lateral direction (lateral direction) acceleration sensor, a vehicle speed sensor, a steering angle sensor, a wheel speed sensor, a roll angle sensor, and a turning direction sensor. At least one of them is used.

  The vehicle travel state determination unit 62 is realized by the arithmetic processing function of the control device (CPU) 26 described above, and compares the detection signal supplied from the vehicle travel state detection unit 61 with a reference value prepared in advance. Judgment processing about the running state of the car is performed.

  The seat belt device control unit 63 includes the arithmetic processing function of the control device (CPU) 26 described above, and an R side motor drive control unit 35 and an L side motor drive control unit 36. The belt driving unit 64 is the retractor 16 described above, and more specifically, the R side motor 51 and the L side motor 52 described above.

  Next, referring to the flowchart shown in FIG. 5, an example of operation control of the seat belt device 10 performed by the seat belt device controller 64 based on the configuration of the control system shown in FIGS. 2 to 4. explain. The flowchart of FIG. 5 shows the flow of control operation after the occupant 11 is seated on the seat 12, the belt 13 is attached to his / her body, the tongue plate 17 is connected to the buckle 18, and the buckle switch 19 is turned on. . In this example, an example of the R-side motor 51 will be described.

  When the occupant 11 sits on the seat 12, the belt 13 is wound around the body, and the tongue plate 17 is coupled to the buckle 18 (R side buckle 47R), the belt 13 is attached to the occupant 11 body. At this time, the buckle switch 19 is turned on (step S11).

  In the seat belt device 10 in which the belt is mounted on the body of the occupant 11, personal information and setting information of the occupant 11 are acquired as basic operations. It is assumed that occupant information and setting information are prepared in advance and held in the recording unit 37 shown in FIG. Crew information includes gender information, physique information, and the like. The setting information is information set as a preference according to the intention of the occupant 11.

  Next, based on the acquired occupant information and setting information, the R-side motor 51 is operated, the belt winding operation by the belt reel 22 is performed, and the adjustment is performed until the fitted state of the seat belt is good.

  On the premise of the above basic operation, the characteristic operation of the present invention is carried out as shown in FIG.

  The occupant 11 who has boarded the seat 12 is controlled to maintain its position and posture by the seat belt device 10. As described above, the belt winding operation for the holding control is preferably selected according to the first control mode (rotation angle control) or the second control mode (current control). Has been done.

  Therefore, in the first step S11, it is determined whether the rotation angle control (first control mode) or the current control (second control mode). If it is rotation angle control, the process proceeds to step S12, and if it is current control, the process proceeds to step S13.

  In step S12, it is determined whether or not the winding position detection unit 25 is abnormal. If NO (normal) in step S12, the rotation angle control is continued in step S15, and if YES (abnormal), the current control is switched to step S14.

  In step S13, it is determined whether or not the motor current sensor 29 is abnormal. If NO (normal) in step S13, current control is continued in step S17, and if YES (abnormal), the control is switched to rotation angle control in step S16.

  After any of the above steps S14 to S17 is executed, the above processing procedure is repeated.

  Note that the vehicle travel state detection unit 61 and the vehicle travel state determination unit 62 shown in FIG. 4 detect and determine when an emergency operation or unstable behavior occurs in the traveling vehicle. The seat belt device control unit 63 preferably selects rotation angle control or current control in accordance with emergency operation or behavioral instability. Since the urgency is low when the behavior is unstable, the rotation angle control is selected. Normally, the operation control of the seat belt device 10 is executed in the first control mode, that is, the rotation angle control. Therefore, according to the control flow shown in FIG. 5, the procedure of step S11, step S12, step S14 or step S15 becomes the main flow of control.

  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 present invention provides a state detection system for evaluating a motor drive amount for drive control of a motor for pulling in / out of a belt, and includes two systems of a winding position detection means and a motor current detection means, and any one of the state detection systems This is used to maintain occupant retention control even if a failure occurs.

It is a side view which shows the mounting state of the seatbelt apparatus in a vehicle. It is a figure which shows the principal part structure of the retractor of the seatbelt apparatus which concerns on embodiment of this invention. 1 is a block diagram illustrating an overall configuration of a control system for a seat belt device according to the present embodiment. It is a block diagram which shows the principal part structure of the control system of the seatbelt apparatus which concerns on this embodiment. It is a flowchart which shows the basic operation control of the seatbelt apparatus which concerns on this embodiment.

Explanation of symbols

10 Seat belt device 11 Crew 12 Seat
13 Belt 16 Retractor
22 Belt reel 23 Motor 25 Winding position detector 26 Controller (CPU)
28 energization amount adjustment unit 29 motor current sensor 61 vehicle running state detection unit 62 vehicle running state determination unit 63 seat belt device control unit

Claims (3)

In a vehicle seat belt apparatus including an electric pretensioner including a belt reel that winds up a belt and a motor that drives the belt reel and pulls in the belt.
Winding position detection means for detecting the winding position of the belt reel;
Motor current detection means for detecting an energization amount to the motor;
Control means for controlling the drive amount of the motor by controlling an energization amount to the motor,
The control means controls a first control mode for controlling the energization amount based on a detection value of the winding position detection means, and a second control mode for controlling the energization amount based on a detection value of the motor current detection means. A vehicle seat belt device comprising a control mode.   First failure detection means for detecting a failure of the winding position detection means is provided, and when the first failure detection means detects a failure of the winding position detection means, the first control mode is disabled. The vehicle seat belt device according to claim 1.   A second failure detection means for detecting a failure of the motor current detection means, and the second control mode is invalidated when the second failure detection means detects a failure of the motor current detection means; The vehicle seat belt device according to claim 1.

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