JP5268807B2 - Vehicle seat belt device - Google Patents

Description

  The present invention relates to a vehicle seat belt device for restraining an occupant seated in a vehicle by webbing.

  In recent years, as a seat belt device, a webbing that has been retracted by a motor as required to obtain appropriate occupant restraint according to the vehicle state has been developed (for example, see Patent Document 1).

By the way, when traveling on a continuous curved road or a slippery road surface, the upper body of the occupant seated on the seat may be swung back and forth, and left and right. It is rare.
On the other hand, sensors that detect the unstable behavior of the vehicle are connected to the controller of the above-described seat belt device, and when the unstable behavior of the vehicle is detected, the motor is controlled by the controller, so that the occupant is webbed. It is being considered to restrain the upper body.

JP 2007-45182 A

  However, the above-described seat belt device has a basic configuration in which the controller determines the signal and controls the motor when a signal is input to the control unit from sensors that detect the unstable behavior of the vehicle. If a failure occurs in the sensors or the like after the occupant restraint control is started, there is a concern that the occupant restraint by the motor is continued more than necessary and the comfort of the occupant is impaired.

  Accordingly, the present invention is intended to provide a vehicle seat belt device capable of improving passenger comfort by preventing the passenger from being restrained by the motor more than necessary.

The invention according to claim 1, which solves the above problem, is a belt reel (for example, a belt reel 12 in an embodiment described later) around which a webbing is wound, and a motor (for example, a later described motor) that rotationally drives the belt reel. When the motor 10) in the embodiment is driven in the forward rotation direction, which is the direction in which the motor pulls in the webbing, the motor and the belt reel are maintained in a connected state, and then the motor is driven in the reverse rotation direction, A clutch (for example, a clutch 20 in an embodiment described later) that disconnects the motor and the belt reel, and vehicle state detection means (for example, a longitudinal acceleration sensor 30 in an embodiment described later, lateral) the acceleration sensor 31, a yaw rate sensor 32), in response to the detected vehicle condition by the vehicle state detecting means, Set the winding target position of the serial webbing, said current control means for the motor is rotated in the forward direction at a predetermined energization amount (e.g., current control means 35 in the embodiment) and detection of the vehicle state detecting means Based on the result, it is determined whether or not occupant restraint by webbing is necessary, and a restraint necessity determining unit (for example, restraint necessity determining unit 34 in an embodiment described later) for outputting the determination signal, and the restraint necessity determining unit. Energization stopping means for stopping energization for driving the motor in the forward rotation direction when the output of the determination signal requiring restriction by the operation continues for a set time or longer (for example, energization stopping means 36 in an embodiment described later); , Provided.
As a result, while the vehicle is running, the vehicle state is detected by the vehicle state detection means, and based on the detection result, the restraint necessity determination means determines whether the passenger is required to be restrained by webbing.
If the output of the determination signal that requires occupant restraint continues for a set time after the restraint necessity determination means first outputs the determination signal that requires occupant restraint, the energization stop means Stop energization of the motor, thereby stopping occupant restraint by webbing.

  According to a second aspect of the present invention, in the vehicle seat belt device according to the first aspect, the energization stop means outputs an abnormality determination signal when energization of the motor is stopped. It is characterized by.

  According to the first aspect of the present invention, the energization of the motor is forcibly stopped when the output of the determination signal requiring occupant restraint is continued for a set time that cannot be normal. The occupant restraint by the motor is not continued more than necessary, and the occupant is not discomforted by the unnecessary restraint.

  According to the second aspect of the present invention, the abnormality determination signal is output when the energization stopping unit stops energization of the motor, so that it is possible to quickly detect abnormality of the sensors.

1 is a schematic configuration diagram of a seat belt device according to an embodiment of the present invention. It is a schematic block diagram of the retractor and controller of the seatbelt apparatus of one Embodiment of this invention. It is a schematic block diagram of the retractor of the seatbelt apparatus of one Embodiment of this invention. It is a flowchart which shows the flow of control of the seatbelt apparatus of one Embodiment of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows an overall schematic configuration of a seat belt device 1 according to the present invention. In FIG. 1, reference numeral 2 denotes a seat on which an occupant 3 is seated. The seat belt device 1 of this embodiment is a so-called three-point seat belt device, and a webbing 5 is drawn upward from a retractor 4 attached to a center pillar (not shown), and the webbing 5 is supported on the upper side of the center pillar. The tip of the webbing 5 is fixed to the vehicle body floor via an outer anchor 7 near the outside of the passenger compartment of the seat 2. A tongue plate 8 is inserted between the through anchor 6 and the outer anchor 7 of the webbing 5, and the tongue plate 8 can be attached to and detached from the buckle 9 fixed to the vehicle body floor of the seat 2 on the inner side of the vehicle body. It has become.
The webbing 5 is wound around the retractor 4 in the initial state, and the occupant 3 pulls it out by hand to fix the tongue plate 8 to the buckle 9, thereby restraining the chest and abdomen mainly of the occupant 3 with respect to the seat 2. To do. Further, the seat belt device 1 automatically performs the winding adjustment of the webbing 5 by the electric motor 10 when the behavior of the vehicle becomes unstable.

  As shown in FIG. 2, the retractor 4 has a webbing 5 wound around a belt reel 12 rotatably supported by a casing (not shown), and a shaft of the belt reel 12 projects from one end side of the casing. . The belt reel 12 is connected to the rotating shaft 10 a of the motor 10 via a power transmission mechanism 13 so as to be interlocked. The power transmission mechanism 13 decelerates the rotation of the motor 10 and transmits it to the belt reel 12. Further, the retractor 4 is provided with a winding spring (not shown) that urges the belt reel 12 in the webbing winding direction. When the belt reel 12 and the motor 10 are separated by a clutch 20 described later, the retractor 4 Tension acts on the webbing 5.

Further, the retractor 4 is provided with a rotation sensor 11 (position detection means) for detecting the rotation position of the belt reel 12. The rotation sensor 11 includes, for example, a magnetic disk in which different magnetic poles are alternately magnetized along the circumferential direction and rotates integrally with the belt reel 12, and a pair disposed in the vicinity of the outer peripheral edge of the magnetic disk. And a sensor circuit for processing a detection signal of the Hall element, and a pulse signal processed by the sensor circuit is output to the controller 21.
In this case, the pulse signal input from the sensor circuit to the controller 21 according to the rotation of the belt reel 12 is used to detect the rotation amount, rotation speed, rotation direction, and the like of the belt reel 12. That is, the controller 21 detects the amount of rotation of the belt reel 12 (the amount of winding / drawing of the webbing 5) by counting the pulse signal, and calculates the change rate (frequency) of the pulse signal to calculate the belt reel. 12 is obtained, and the rotation direction of the belt reel 12 is detected by comparing the rising edges of the waveforms of both pulse signals.

FIG. 3 shows a specific configuration of the power transmission mechanism 13.
In the power transmission mechanism 13, a sun gear 14 is integrally coupled to an external tooth 15 for driving input, and a carrier 17 that supports a plurality of planetary gears 16 is coupled to the shaft of the belt reel 12. A plurality of ratchet teeth (not shown) are formed on the outer peripheral side of the ring gear 18 meshed with the planetary gear 16, and these ratchet teeth constitute a part of the clutch 20. The clutch 20 appropriately disconnects the power transmission system between the motor 10 and the belt reel 12 by controlling the driving force of the motor 10 by the controller 21.

  The motor-side power transmission system 22 of the power transmission mechanism 13 is capable of rotating coaxially and integrally with the first connect gear 23 having a small diameter that is always meshed with the external teeth 15 that are integral with the sun gear 14. A large-diameter second connect gear 24, and first and second idler gears 26 that are between the second connect gear 24 and the motor gear 25 (integrated with the rotary shaft 10a of the motor 10) and are always meshed so as to be able to transmit power. 27. The driving force in the forward direction of the motor 10 is transmitted to the second and first connect gears 24 and 23 through the gears 25, 27 and 26, and further transmitted to the sun gear 14 through the external teeth 15, and then to the planetary gear 16. It is transmitted to the belt reel 12 through the carrier 17. The driving force in the forward rotation direction of the motor 10 rotates the belt reel 12 in the direction in which the webbing 5 is pulled. However, the driving force transmitted from the sun gear 14 to the planetary gear 16 is all transmitted to the carrier 17 side as described above when the ring gear 18 is fixed. However, when the ring gear 14 is free to rotate, the planetary gear is transmitted. The ring gear 18 is idled by 16 rotations. The clutch 20 controls the locking and unlocking of the rotation of the ring gear 14 to turn on / off the transmission of the motor driving force to the belt reel 12 (carrier 17).

  The clutch 20 includes the ratchet teeth provided on the outer periphery of the ring gear 18 and a pawl (not shown) that is rotatably supported by a casing (not shown) and whose front end portion can mesh with the ratchet teeth. The meshing with the ratchet teeth is triggered by the rotation in the forward rotation direction of 10, and the meshing with the ratchet teeth is released by the rotation in the reverse rotation direction of the motor 10. Therefore, once the motor 10 is driven in the forward direction, the clutch 20 locks the ring gear 18 to maintain the motor 10 and the belt reel 12 in the connected state, and then when the motor 10 is driven in the reverse direction. Then, the lock of the ring gear 18 is released, and the motor 10 and the belt reel 12 are cut off.

Incidentally, on the input side of the controller 21, in addition to the rotation sensor 11, as shown in FIG. 2, a longitudinal acceleration sensor 30 for detecting the longitudinal acceleration of the vehicle, and a lateral acceleration sensor for detecting the lateral acceleration of the vehicle. 31, a yaw rate sensor 32 that detects angular acceleration in the yaw direction of the vehicle, a current sensor 40 that detects current supplied to the motor 10, and the like are connected. Further, the controller 21 transmits and receives signals to and from other system controllers such as a VSA (Vehicle Stability Assist) system 33 through an in-vehicle communication network.
In this embodiment, the longitudinal acceleration sensor 30, the lateral acceleration sensor 31, the yaw rate sensor 32, the communication unit with the VSA system 33, and the like constitute vehicle state detection means for detecting the state of the vehicle.

  Further, the controller 21 determines whether or not the occupant is restrained by the motor 10 based on input signals from the lateral acceleration sensor 31, the yaw rate sensor 32, and the like, and a restraint necessity determining unit 34 that outputs the determination signal, and the vehicle. The current control means 35 for controlling the amount of current to be supplied to the motor 10 in accordance with the state and the determination signal requiring restriction by the restriction necessity determination means 34 are output continuously for a set time or longer. Power supply stopping means 36 for stopping power supply. A warning lamp 41 (abnormality notification means) is connected to the output side of the controller 21. The energization stopping means 36 outputs an abnormality determination signal when the energization of the motor 10 is stopped, and the warning lamp 41 is turned on in response to the abnormality determination signal.

  The controller 21 receives a vehicle state signal input from the lateral acceleration sensor 31, the yaw rate sensor 32, or the like. When occupant restraint by the webbing 5 is necessary, the current control means 35 causes the motor 10 to respond to the vehicle state at that time. The amount of current supplied to the belt reel 12 is controlled. For example, the rotation amount of the belt reel 12 is fed back to the target position while the rotation sensor 11 feeds back the rotation position of the belt reel 12. Increase or decrease the current.

Hereinafter, an example of the control by the controller 21 of the seat belt apparatus 1 will be described with reference to the flowchart of FIG. The control in this example assumes, for example, a situation where the vehicle travels on a continuous curved road or a slippery road surface.
First, in step S101, if there is occupant individual information or preset information, it is read, and in step S102, the slack of the webbing 5 is removed by winding the motor 10. In step S103, it is determined whether the webbing 5 is in close contact with the occupant and the slack has been removed. If no, the process returns to step S102, and the winding operation by the motor 10 is continued until Yes.
If Yes in step S103, the process proceeds to the next step S104, and the rotational position of the belt reel 12 at this time is stored as the winding reference position.

In step S105, whether or not the vehicle state has changed from a prescribed state beyond an allowable amount, for example, whether or not the detected values of the lateral acceleration sensor 31, the yaw rate sensor 32, etc. have exceeded a prescribed value, It is determined whether an operation signal is transmitted from 33 or the like. If yes, the process proceeds to step S106. If no, the process waits.
In step S106, the rotation target position X1 of the belt reel 12 (the winding target position of the webbing 12) is set according to the current vehicle state and the like, and the timer for managing the current control time is reset and continued. In step S107, the motor 10 is rotated in the forward rotation direction with a preset initial current amount.
In step S108, it is determined whether or not the current position X of the belt reel 12 is not equal to the target position X1. If Yes, the process proceeds to step S109. If No, the process proceeds to step S113.
In step S109, it is determined whether or not the deviation width (deviation) between the current position X and the target position X1 is greater than or equal to a set value. If yes, the process proceeds to step S110. If no, the process proceeds to step S113. Proceed to
In step S110, it is determined whether or not the current position X is smaller than the target position X1, and if yes, the process proceeds to step S111 to increase the energization amount to the motor 10, and if no, step It progresses to S112 and the energization amount with respect to the motor 10 is decreased. After these steps S111 and S112, the process proceeds to step S113.
In step S113, it is determined whether the vehicle state is stable based on input signals from the lateral acceleration sensor 31, the yaw rate sensor 32, and the like. If yes, the process ends. Proceed to S114.

In step S114, it is determined whether or not the set time has elapsed since it was first determined that the vehicle state has changed from the prescribed state beyond the allowable amount (steps S105 and S106). Advances to step S115, and in the case of No, the process returns to step S108 again to continue the increase / decrease control of the energization current of the motor 10. The set time used in step S114 is set to a long time that cannot be normal passenger restraint.
When the set time has passed and the process proceeds to step S115, the energization of the motor 10 is stopped, the restraint control by the webbing 12 is forcibly terminated, and the warning lamp 41 is lit to cause a failure in the sensors on the input side. Inform the crew that this occurred.
Note that the processing of steps S114 and S115 corresponds to the function of the power supply stopping means 36.

  As described above, in the seatbelt device 1, the energization stop unit 36 stops energization of the motor 10 when the determination signal that requires constraint is continuously output from the constraint necessity determination unit 34 for a set time or longer. Since the restraint control is forcibly terminated, the webbing 5 does not continue to restrain the occupant more than necessary even in a situation where some kind of failure occurs in the sensors and the original restraint control cannot be performed. Unnecessary restraint by 5 does not give a passenger discomfort.

  Further, in the seat belt device 1, when the energization stop means 36 stops energization to the motor 10 and ends the restraint control, the warning lamp 41 is turned on because there is an abnormality in the sensors and the like. It is possible to promptly notify the occupant of a malfunction.

  In addition, this invention is not limited to said embodiment, A various design change is possible in the range which does not deviate from the summary. For example, in the above embodiment, when the energization stopping unit 36 stops energizing the motor 10, an abnormality determination signal is output to the warning lamp 41. However, the abnormality determination signal may be other VSA or the like. You may make it transmit to the system of.

DESCRIPTION OF SYMBOLS 1 ... Seat belt apparatus 10 ... Motor 12 ... Belt reel 30 ... Longitudinal acceleration sensor (vehicle state detection means)
31 ... Lateral acceleration sensor (vehicle state detection means)
32 ... Yaw rate sensor (vehicle state detection means)
33 ... VSA system (vehicle state detection means)
34 ... Restriction necessity determination means 35 ... Current control means 36 ... Energization stop means

Claims (2)

A belt reel around which webbing is wound;
A motor for rotationally driving the belt reel;
When the motor is driven in the forward rotation direction, which is the direction in which the webbing is pulled, the motor and the belt reel are maintained in a connected state, and then when the motor is driven in the reverse rotation direction, the motor and the belt reel are connected. A clutch to be disengaged,
Vehicle state detection means for detecting the state of the vehicle;
Current control means for setting the winding target position of the webbing according to the vehicle state detected by the vehicle state detection means, and for rotating the motor in the normal rotation direction by a predetermined energization amount ;
Determining whether or not occupant restraint is required by the webbing based on the detection result of the vehicle state detecting means, and outputting a determination signal for the restraint necessity determination means;
Energization stopping means for stopping energization for driving the motor in the forward rotation direction when output of a determination signal requiring restriction by the restriction necessity determination means continues for a set time or longer. A vehicle seat belt device.   2. The vehicle seat belt device according to claim 1, wherein the energization stopping unit outputs an abnormality determination signal when the energization of the motor is stopped.

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