JP4416276B2 - Seat belt device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a seatbelt device that restrains an occupant to a seat by a webbing (belt) and protects the occupant in the event of a vehicle collision or the like, and in particular, to improve the occupant restraint of the seatbelt device and the comfort of the webbing. The present invention relates to a seat belt device.
[0002]
[Prior art]
An example of a conventional seat belt device is No. 2-7094. In this seat belt device, when the brake is stepped on at a low speed, or when the accelerator is closed at a high speed, the webbing is wound by the motor to restrain the occupant.
[0003]
[Problems to be solved by the invention]
However, in the above-configured seat belt device, the webbing is wound up when the brake is depressed at a predetermined speed or more, or the accelerator is closed, but the passenger is restrained regardless of whether it is actually necessary. Can be caused.
[0004]
Therefore, an object of the present invention is to provide a seat belt device that reduces the uncomfortable feeling caused by the occupant's winding when detecting the braking of the host vehicle and winding the webbing.
[0005]
In addition, the present invention provides a seat belt device that does not wind up the webbing to the extent that the occupant is tightened when it is not necessary, winds the webbing to the extent that it does not give a feeling of pressure, and winds the occupant when necessary. The purpose is to do.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a seat belt device of the present invention is a seat belt device that restrains a vehicle occupant to a seat by webbing, and a webbing take-up device that winds up the webbing and a webbing that is pulled out from the webbing take-up device Detecting means for detecting a vehicle and outputting a braking detection signal, and a deceleration detecting means for detecting a deceleration of the vehicle and outputting a deceleration signal And a feed amount detecting means (encoder) for detecting the webbing feed amount, and a control for controlling winding of the webbing based on at least a mounting signal, a braking detection signal, a deceleration signal, and a webbing feed amount (encoder output). And the controller is configured to feed the origin by which the webbing winding stops in response to the webbing attachment signal. A first process in which the webbing take-up means winds up to the origin position), and a second stage in which the webbing is fed out from the origin feed amount (origin position) by a predetermined amount to set the initial feed amount (initial position) to ease the occupant's restraint. , A third step of winding the webbing to the first feed amount (first position) according to the braking signal, and a first feed amount (first position) according to the deceleration signal And a fourth process of winding up to a second feed amount (second position) that is smaller than and larger than the origin feed amount.
[0007]
Preferably, the first extension amount is set to a position that is between the initial extension amount and the origin position and does not give a sense of pressure to the occupant. The second extension amount exists between the first extension amount and the origin extension amount, and is a binding force that does not change the driving posture of the driver, thereby enabling a collision avoidance operation.
[0008]
The brake detection means detects that the brake pedal has been depressed and determines that the brake is being applied. The deceleration detection means detects an acceleration sensor provided in the vehicle, and generates an output when the deceleration exceeds a predetermined value.
[0009]
The winding device has a configuration in which the rotation of the motor rotates the reel around which the webbing is wound, and enables the winding and feeding of the webbing by rotating the reel forward and backward.
[0010]
The control unit controls the winding of the webbing in multiple (plural) stages between the initial webbing feed amount and the origin position, thereby ensuring both safety by occupant restraint and avoidance operation by relaxation of restraint. .
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a vehicle seat belt device. The seat belt system includes an electric winder 100 that winds one end of a webbing 302 that restrains an occupant to a seat 301 with an electric motor, a through anchor 303 that folds the webbing 302 in the vicinity of the shoulder of the occupant, and a webbing 302. A tongue plate 305 that engages with a buckle 304 disposed on the waist, an anchor plate 306 that fixes the other end of the webbing 302 to the vehicle body, a buckle switch 307 that is built into the buckle 304 and detects webbing attachment, and is not shown. The brake pedal switch 401 that detects the depression of the brake pedal, the acceleration sensor 402 that detects the acceleration (and deceleration) of the vehicle, and the control unit 200 that controls the motor 110 of the winding device 100 are configured.
[0012]
FIG. 2 is an explanatory diagram schematically illustrating the configuration of the electric winding device 100. In the figure, an electric winding device 100 includes a frame 101. The frame 101 is provided with a reel 103 around which the webbing 302 is wound, and a reel shaft 103a that is coupled at the left end side of the reel 103 and serves as a central axis of reel rotation. The reel shaft 103a may be a torsion shaft for the purpose of energy absorption (EA). A seat belt locking mechanism 102 that locks the drawer of the webbing 302 is provided at the right end of the reel shaft 103a. The seat belt lock mechanism 102 includes an operation of locking the belt drawer when a predetermined deceleration acts on the vehicle, and an operation of locking the drawer of the webbing 302 when the webbing 302 is pulled out at a predetermined acceleration. Yes. The lock mechanism 102 is further provided with an electromagnetic actuator 112 (described later) for forcibly operating the lock mechanism 102 in response to a command signal. The operation of the electromagnetic actuator 112 is controlled by the output of the control unit 200 described later. The seat belt lock mechanism 102 is configured so that the webbing 302 can be taken up by the electric motor 110 even when the webbing 302 is in a locked-out state.
[0013]
The pretensioner 104 is operated by the output of a collision detector (not shown), rotates the reel shaft 103a in the seat belt winding direction, forcibly winds the seat belt, and restrains the occupant to the seat. The pretensioner 104 is, for example, an explosive pretensioner, and includes a gas generator, a cylinder that seals gas generated from the gas generator, a piston that moves in the cylinder by gas pressure, and movement of the piston via a clutch mechanism. And a transmission mechanism that converts the rotational movement of the reel shaft 103a.
[0014]
The reel 103 is rotationally driven by a motor 110 through power transmission means. The power transmission means includes, for example, a pulley 105 fixed to the reel shaft 103a, a pulley 106 fixed to the shaft of the electric motor 110, a power transmission belt 107 disposed between both pulleys, and the like. The motor 110 is, for example, a DC motor, and is driven and controlled by a level signal or a PWM signal. The motor 110 is fixed to the frame 101 at at least two points, and operates according to the output of the control unit 200. The motor 110 is provided with an encoder 111, which detects the rotation of the rotation shaft of the motor 110 and transmits signals φ 1 and φ 2 indicating the rotation direction and the rotation number (rotation angle amount) to the control unit 200.
[0015]
FIG. 3 is a block diagram showing a part related to the present invention in the control system of the seat belt apparatus. As described above, the buckle switch 307 is built in the buckle 304, detects whether or not the webbing 302 is attached, and supplies a signal corresponding to the presence or absence of the attachment to the control unit 200. The brake pedal switch 401 detects the depression of the brake pedal by an occupant and outputs a braking signal to the control unit 200. The acceleration sensor 402 detects the deceleration of the host vehicle and supplies a deceleration signal to the control unit 200.
[0016]
The control unit 200 includes, for example, a microcontroller and includes a CPU that executes a control program, a RAM that stores processing data, a ROM that stores programs, a built-in timer, a counter, and an A / D converter. Input / output interface etc. The control unit 200 performs processing (reading, etc.) of the supplied signal by a DMA operation of the input / output interface or by an interrupt processing of a CPU described later.
[0017]
The drive circuit 210 drives the motor 110 by power amplification of the level signal (or PWM signal) supplied from the control unit 200. For example, the encoder 111 and a magnetized disk in which N-pole and S-pole magnetic markers are alternately formed on the outer circumference provided on the rotating shaft of the motor 110 and an output that is shifted from each other by a quarter cycle are arranged. The two hall sensors detect the rotation of the rotating shaft of the motor 110 to generate two-phase pulse trains φ 1 and φ 2, and transmit information on the rotation direction and the rotation amount (rotation angle) to the control unit 200. Since the rotation shaft of the motor 110 is interlocked with the reel 103, the rotation angle corresponds to the webbing winding amount and the drawing amount. The pulse trains φ 1 and φ 2 are digitized by an up / down counter in the input / output interface of the control unit 200. The value of the up / down counter increases corresponding to the withdrawal of the webbing 302 and decreases corresponding to the winding. Therefore, if counting is started from a state where the webbing 302 is completely stored in the winding device 100, the encoder output represents the amount of webbing 302 drawn (see FIG. 9 described later).
[0018]
FIG. 4 is a flowchart schematically showing a main routine of the control unit 200. First, when power is supplied, initialization processing is performed (S10). This includes resetting each flag of the flag register (or RAM flag area) and setting a predetermined value. Next, the timer interrupt operation of the CPU is validated, and a program for monitoring the input to the control unit 200 is executed every predetermined time (S20).
[0019]
FIG. 5 shows an example of input monitoring by interrupt processing (S20). First, the output of the buckle switch 307 is read (S202), and it is determined whether or not the webbing 302 is attached (S204). If it is mounted (S204; Yes), the webbing mounting flag in the flag register is set (flag on) (S206). When it is not worn (S204; No), the webbing wearing flag is reset (flag off) (S208). Next, the output of the brake pedal switch 401 is read (S210), and it is determined whether braking has been performed (S212). When braking is performed (S212; Yes), a braking flag is set (S214). When braking is not performed (S212; No), the brake flag is reset (S216). Next, the output of the acceleration sensor is read (S218), and this output indicates the deceleration, and for example, it is determined whether or not it exceeds a predetermined value corresponding to the impact of the collision (S220). When the predetermined value is exceeded (S220; Yes), a deceleration excess flag is set (S222). When the predetermined value is not exceeded (S220; No), the deceleration excess flag is reset (S224). Thereafter, the timer interrupt process is finished, and the process returns to the process immediately before the interrupt process. This interrupt process is repeated at a predetermined cycle.
[0020]
The control unit 200 monitors the use state of the webbing 302 in the main routine. If applicable, the pre-mounting control process (S30), the storage control process (S40), the mounting origin setting process (S50), and the initial stage Position setting processing (S60),..., Braking control processing (S70), and the like are appropriately performed.
[0021]
In the pre-mounting control (S30), in order to make it easy for the occupant to mount the webbing 302, for example, the motor 110 generates a weak force that does not rotate in the webbing pull-out direction so that the occupant does not need a force to pull out the webbing. . The storage control (S40) performs winding of the webbing 302 whose webbing is released.
[0022]
As shown in FIG. 6, the origin setting process (S50) at the time of wearing is a process of determining the webbing pull-out amount in a state where the passenger is restrained to the seat when the passenger wears the webbing. As shown in FIG. 9, when the occupant pulls out the webbing 302 and engages the buckle 304 and the tongue plate 305 to mount the webbing, the buckle switch 307 detects the webbing mounting and sets the webbing mounting flag ( S206). When the control unit 200 detects that the webbing attachment flag is set in the main routine (S502; Yes), it rotates the motor 110 in the winding direction to wind up the webbing 302 (S504). The winding force is, for example, a retraction force of 30 to 60 N at the winding device outlet. The control unit 200 monitors the encoder output to determine whether or not the webbing 302 is no longer wound (S506). When the encoder output decreases (S506; No), the winding is continued until the winding is stopped (S504). When the encoder output is stopped (S506; Yes), the occupant is restrained by the seat by winding the webbing 302. The webbing drawing position (drawing amount) is stored in the register (or RAM) as the origin position. A mounting origin setting flag indicating that the origin position has been set is set (S508). The winding of the motor 110 is stopped (S510). This attachment origin flag is reset when the webbing attachment is released. Thereafter, the process returns to the original process.
[0023]
Next, as shown in FIG. 7, when it is determined that the mounting origin setting flag has been set in the main routine (S602; Yes), an initial position setting process for giving moderate slack to the webbing 302 is performed. The control unit 200 rotates the motor 110 in the pull-out direction of the webbing 302 to loosen the webbing 302 from the wound state (S604). The control unit 200 monitors the encoder output (S606), and when it is pulled out from the mounting origin position by a predetermined amount, for example, about 20 to 50 mm in webbing length (S606; Yes), the encoder output at that time is the initial position. Is stored in a register (or RAM). An initial position maintenance flag indicating that the webbing should be maintained at the initial position is set (S608). The controller 200 stops the motor 110 and stops the webbing withdrawal (S610). Thereafter, the process is returned to the main routine. Although not shown, when the motor 110 is stopped, the webbing can be pulled out except in an emergency. For this reason, the pull-out amount of the webbing 302 is changed due to a change in the posture of the occupant. At this time, if the initial position maintaining flag is set, webbing withdrawal / winding control is performed so as to maintain the webbing withdrawal amount at the initial position.
[0024]
In the main routine, when the driver depresses the brake pedal 401, webbing braking control is performed under a predetermined condition (S70).
[0025]
First, the webbing wearing of the occupant is determined by setting the webbing wearing flag (S702). If the flag is not set, the processing of this routine is not necessary (S702; No), and the webbing winding is performed in the above-described storage processing (S40).
[0026]
When the webbing is attached (S702; Yes) and it is determined that the brake is operated by the brake flag set (S704; Yes), the initial position maintenance flag is reset, and the webbing position can be changed from the initial position ( S706). Next, as shown in FIG. 9, the control unit 200 winds and drives the motor 110 to wind up the webbing 302 to the first position, and as much excess slack as possible without giving the passenger a feeling of pressure. The removed state is set (S708). When the brake flag is not set (S704; No), the winding (S706, S708) is not performed.
[0027]
Next, the control unit 200 determines whether or not a flag is set equal to or greater than a predetermined deceleration value corresponding to the occurrence of an impact such as a collision (S710). If the flag is set (S710; Yes), the initial position maintenance flag is reset, and the webbing 302 can be tightened (S712). The control unit 200 winds and drives the motor 110 to wind the webbing 302 to the second position. This winding up maximizes the output of the motor to remove slack and firmly restrain the occupant to the seat. This winding is continuously performed for a predetermined time even if the deceleration becomes a predetermined value or less (S714). If the flag is not set beyond the predetermined deceleration value (S710; No), the winding process (S712, S714) is not performed.
[0028]
As shown in FIG. 9, the first position of the webbing pull-out amount described above is between the initial position and the origin position, and is set to a position that does not give the passenger a feeling of pressure. The second position is set between the first position and the origin position, and is set in a range in which the collision avoidance operation can be performed while the driver is restrained.
[0029]
Next, it is determined whether both the braking flag and the deceleration predetermined value or more flag are reset (S716). When both flags are reset and the webbing winding time to the second position of the webbing has elapsed (S716; Yes), the initial position maintenance flag is set. As a result, the webbing drawer position is returned to the slack initial position (S718). When both the braking flag and the deceleration predetermined value or more flag are not reset ( S716 ; No), this routine is terminated and the process returns to the main routine.
[0030]
In this way, the webbing retract control of the seat belt device is performed by repeatedly executing the main routine.
[0031]
【The invention's effect】
As described above, according to the seat belt device of the present invention, when it is not necessary, the webbing is not wound up to the extent that the occupant is tightened. Since it is tightened, the occupant restraint can be improved in the event of an emergency such as a collision, and a comfortable wearing state without a sense of incongruity can be maintained in non-emergencies (non-collisions).
[Brief description of the drawings]
FIG. 1 is an explanatory diagram illustrating a configuration of a seat belt device.
FIG. 2 is an explanatory view illustrating a configuration example of a webbing take-up device.
FIG. 3 is a block diagram illustrating a control system of the seat belt device.
FIG. 4 is a flowchart illustrating an example of overall control of the seat belt device.
FIG. 5 is a flowchart for explaining input monitoring by timer interrupt processing;
FIG. 6 is a flowchart for explaining origin position setting when a webbing is mounted.
FIG. 7 is a flowchart for explaining an initial position setting for webbing attachment;
FIG. 8 is a flowchart illustrating webbing control at the time of brake operation.
FIG. 9 is a graph for explaining a webbing withdrawal / winding control profile in the webbing winding control according to the present invention;
[Explanation of symbols]
100 Webbing retractor 200 Control unit 307 Buckle switch 401 Brake pedal switch 402 Acceleration sensor

Claims (3)

A seat belt device for restraining a vehicle occupant to a seat by webbing,
A webbing take-up device for taking up the webbing;
Webbing wearing detection means for detecting the wearing of the webbing drawn from the webbing take-up device and outputting a wearing signal;
Braking detection means for detecting braking of the vehicle and outputting a braking detection signal;
Deceleration detection means for detecting deceleration of the vehicle and outputting a deceleration signal;
A feed amount detecting means for detecting a feed amount of the webbing;
A control unit that controls winding of the webbing based on at least the mounting signal, the braking detection signal, the deceleration signal, and the webbing feed amount;
The controller is
First monitoring the input of the mounting signal, the braking detection signal, and the deceleration signal, and causing the webbing take-up means to take up the webbing up to an origin feed amount at which winding is stopped according to the webbing mounting signal. Process,
A second step of setting the webbing by a predetermined amount from the origin feed amount and setting the initial feed amount by relaxing the occupant's restraint;
A third step of causing the webbing take-up means to take up the webbing to a first payout amount in response to the braking signal to reduce slack;
When the braking signal is detected and the deceleration signal exceeds a predetermined value, the webbing is a second feeding amount smaller than the first feeding amount and larger than the origin feeding amount , and the occupant A fourth step of causing the webbing take-up means to wind up to the extent that the collision avoidance operation can be performed while being restrained .
Performing the seat belt device. The seat belt device according to claim 1, wherein the predetermined value of the deceleration signal corresponds to an impact of a collision. Furthermore, the seatbelt apparatus of Claim 1 or 2 provided with the pretensioner which act | operates by the output of a collision detector and forcibly winds up the webbing .

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