JP2001114068A - Seat belt pretensioner mechanism and seat belt pretension method - Google Patents

Abstract

(57) [Summary] Seat belt pretensioner mechanism 27
A primary gas comprising a pump 66, an accumulator 68 for storing the compressed air produced by the pump 66, and first and second solenoid valves 71, 72 for supplying / stopping the compressed air stored in the accumulator 68 to the cylinder 34. A supply system 61;
A secondary gas supply system 62 for supplying high-pressure gas generated by the ignition of the inflator 77 to the cylinder 34, and a primary gas supply system 61 based on the vehicle speed, the stepping speed of the brake pedal, and the stepping amount of the brake pedal. And a main control unit 55 for operating the secondary gas supply system 62 if necessary. [Effect] The seat belt can be tensioned at an earlier timing before the collision. In addition, it is possible to determine braking for avoiding collision.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seatbelt pretensioner mechanism and a seatbelt pretensioning method suitable for enhancing restraint performance of an occupant.

[0002]

2. Description of the Related Art As a device for improving the occupant restraint performance of a seat belt at the time of a vehicle collision, for example, Japanese Utility Model Application
The one described in -7094, "Emergency Locking Retractor" is known.

As shown in FIG. 2 of the above publication, the control circuit 27 controls the rotation of the motor 9 based on output signals from a brake switch 16 and a vehicle speed sensor 17 as shown in FIG. As shown in the figure, the end of the belt 3 is wound around the winding shaft 2, and the winding shaft 2 is rotated by a motor 9, so that the belt 3 is wound at the time of a brake operation before a vehicle collision and the belt 3 is provided to an occupant. An ELR (emergency locking retractor) to be attached is described.

[0004]

In the above technique, the belt 3 is wound up by the motor 9, so that the brake switch 1
It becomes difficult to instantaneously wind up the belt in a very short time from the generation of the output signal at 6 to the collision.

[0005] When the vehicle speed is equal to or higher than a predetermined value, the belt 3 is tightened every time the brake is depressed even during normal running other than the running immediately before the collision, so that the belt 3 is intimately attached to the occupant, causing discomfort. There is an inconvenience.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a seat belt pre-load device capable of instantaneously winding up a seat belt and restraining an occupant only during a brake operation aimed at avoiding a collision and immediately after a vehicle collision. It is to provide a tensioner mechanism.

[0007]

In order to achieve the above object, a first aspect of the present invention is to supply compressed air or high-pressure combustion gas to a cylinder immediately before and immediately after a vehicle collision to move the piston at a high speed. Thus, in the seat belt pretensioner mechanism for tensioning the seatbelt, the seatbelt pretensioner mechanism includes a pump, an accumulator for storing compressed air produced by the pump, and supplying / compressing the compressed air stored by the accumulator to the cylinder.
A primary gas supply system including a solenoid valve that stops, a secondary gas supply system that supplies high-pressure gas generated by inflator ignition to the cylinder, and a vehicle speed, a brake pedal depression speed, and a brake pedal depression amount. And a control unit for activating the primary gas supply system and, if necessary, for activating the secondary gas supply system.

The control unit determines from the vehicle speed, the stepping speed of the brake pedal and the stepping amount of the brake pedal whether or not the braking is aimed at collision avoidance. , A pump, an accumulator for storing the compressed air produced by the pump, and a primary gas supply system comprising a solenoid valve for supplying / stopping the compressed air stored in the accumulator to the cylinder, and then, if necessary, to ignite the inflator The secondary gas supply system that supplies the high-pressure gas generated in the above to the cylinder is operated.

As a result, in the primary gas supply system, since the compressed air is used as the driving source of the piston, the seat belt can be tensioned at an earlier timing before the collision, and the occupant restraint performance can be improved. it can. Also,
It is possible to determine braking aimed at collision avoidance based on the vehicle speed, brake pedal depression speed, and brake pedal depression amount, and prevent the seat belt from being tensioned during braking during normal driving other than collision avoidance. it can.

If the control unit determines that the collision has been avoided after activating the primary gas supply system, the control unit does not operate the secondary gas supply system and operates the compressed air in the cylinder. Is released to the atmosphere to return the piston to its original position, and a control function of repeatedly operating the primary gas supply system is provided.

After the collision is avoided by braking,
The primary gas supply system is repeatedly operated, and the cost for replacement is reduced as compared with, for example, replacing a gas supply system of a type used up once.

In a preferred embodiment of the present invention, the step of determining whether or not the stepping speed, the stepping amount and the vehicle speed of the brake pedal have exceeded respective threshold values when the brake pedal is stepped down; When the vehicle speeds exceed the respective threshold values, the braking is determined as braking for avoiding a collision, and the compressed air stored in the accumulator is sent to the cylinder driving the seat belt retractor to thereby reduce the seat. A step of retracting the belt to instantly restrain the occupant; a step of determining whether the vehicle body acceleration exceeds a threshold value; and a step of determining that the vehicle has collided with the inflator when the vehicle body acceleration exceeds the threshold value. In addition to the seat belt retraction described above, the high-pressure combustion gas generated by ignition and sent into the cylinder is used for further A step of further restrain the occupant by performing a retraction of safety belt, that consist, characterized in that to restrain the occupant in two stages in the immediately collides with the collision immediately before.

By restraining the occupant not only immediately after the collision but also immediately before the collision, the occupant is restrained at an earlier timing and the occupant is restrained in two stages, thereby improving the performance of restraining the occupant during the collision.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings should be viewed in the direction of reference numerals. FIG. 1 is a perspective view showing a seat belt provided with a seat belt pretensioner mechanism according to the present invention,
The seat belt 10 has an emergency lock type winding device (ELR) 13 with a seat belt pretensioner (hereinafter, referred to as “ELR 13 with a pretensioner”) as a seat belt winding device attached below the center pillar 12 of the vehicle body 11. The upper attachment 15 is attached to the roof side rail 14, the tongue 17 is movably attached in the middle of the webbing 16 extending from the ELR 13 with the print tensioner, the lower attachment 18 is attached to the tip of the webbing 16, and the lower attachment 18 is attached. Installed below the center pillar 12,
A buckle 22 is attached to a floor panel 19 of the vehicle body 11 via a floor fixture 21.
7 is an occupant restraining device that restrains an occupant seated on the seat 24 by connecting the seats 7. Reference numerals 16a and 16b denote a waist belt constituting the webbing 16 and a shoulder belt continuous with the waist belt.

FIG. 2 is a perspective view of an ELR with a pretensioner provided with a seat belt pretensioner mechanism according to the present invention. An ELR 13 with a print tensioner includes an ELR section 26 and a seat belt pretensioner attached to the ELR section 26. And a mechanism 27.

The ELR section 26 is provided with an impact sensing device for locking the pulling out of the webbing 16 due to the inertial force acting on the occupant at the time of a vehicle collision or sudden braking, and can normally pull out the webbing 16 freely. .

The seat belt pretensioner mechanism 27
Compressed air or high-pressure gas is generated, and the webbing 16 is drawn into the ELR section 26 by using the compressed air or high-pressure gas as a driving source. This is a device for improving the restraint performance of the occupant during braking, and comprises an operating unit 30 attached to the side of the ELR unit 26, a detection / control unit described later, and a gas supply unit.

FIGS. 3A and 3B are cross-sectional views of an ELR with a pretensioner provided with a seat belt pretensioner mechanism according to the present invention. FIG. 3A is a cross-sectional view taken along line aa of FIG. FIG. 3B is a sectional view taken along line bb of FIG. 2. 2A, the ELR unit 26 includes a winding shaft 31 for winding the webbing 16. Reference numeral 32 denotes a fixing member for fixing the end of the webbing 16 to the winding shaft 31. The winding shaft 31 is a member that constantly applies a winding force in a direction in which the webbing 16 is wound.

In FIG. 2B, the operating section 30 comprises a gas supply pipe 33 through which compressed air or high-pressure gas passes, a cylinder 34 connected to the gas supply pipe 33, and a piston 35 movably accommodated in the cylinder 34. And this piston 35
, A pinion 37 that meshes with the rack 36, and a rotating shaft 38 that rotates integrally with the pinion 37 and is connected to the winding shaft 31 (see (a)) via a plurality of gears. And a case 41 for accommodating these pinions 37, a plurality of gears and a rotating shaft 38, and a piston 35 and a case 41 for pushing back the piston 35 and the rack 36 moved by the compressed air or high-pressure gas blown into the cylinder 34. And a return spring 42 interposed therebetween. Reference numeral 43 denotes an O-ring.

FIG. 4 is a structural view of the seat belt pretensioner mechanism according to the present invention. The seat belt pretensioner mechanism 27 detects the vehicle speed, the vehicle body acceleration, and the state of the brake pedal to operate the operating section 30. The detection / control unit 50 controls the supply of compressed air or high-pressure gas, and the gas supply unit 60 supplies compressed air or high-pressure gas based on information from the detection / control unit 50.

The detection / control unit 50 includes a brake pedal depression speed sensor 5 for detecting the depression speed of the brake pedal.
1, a brake pedal depression amount sensor 52 for detecting the depression amount of the brake pedal, a vehicle speed sensor 53 for detecting the vehicle speed, and a vehicle acceleration sensor 54 for detecting the acceleration of the vehicle body
And the pedal speed signal PV from the brake pedal depression speed sensor 51, the pedal depression amount signal PA from the brake pedal depression amount sensor 52, the vehicle speed signal VS from the vehicle speed sensor 53, and the acceleration signal AS from the vehicle body acceleration sensor 54.
And a main control unit 55 as a control unit for controlling the supply of compressed air or high-pressure gas to the cylinder 34 based on the above.

A brake pedal depression speed sensor 51, a brake pedal depression amount sensor 52, and a vehicle speed sensor 53
Is a sensor for determining whether or not the depression of the brake pedal by the occupant has been performed to avoid a collision. When all of the vehicle speed, the stepping speed of the brake pedal, and the stepping amount of the brake pedal exceed predetermined values, the control unit 55 determines that braking for avoiding a collision has been performed.

For example, (a) when the brake pedal depressing speed and the brake pedal depressing amount exceed a predetermined value, at a low speed when the vehicle speed is equal to or lower than a predetermined value, and (b) when the vehicle speed exceeds a predetermined value. At the time of braking during normal running in which the brake pedal depression speed and the brake pedal depression amount are equal to or less than predetermined values, it is not determined that the braking is to avoid a collision.

The gas supply unit 60 includes a primary gas supply system 61
And a secondary gas supply system 62. The primary gas supply system 61 generates compressed air and supplies it to the cylinder 34.
The secondary gas supply system 62 generates a high-pressure gas and
4 is a system to supply.

The primary gas supply system 61 includes a pump 66 driven by a motor 65 and a check valve 67 from the pump 66.
And a first solenoid valve 71 which selectively opens and closes the compressed air from the accumulator 68 by opening / closing according to a control signal CS1 from the main control unit 55.
And the control signal C from the main control unit 55
A second solenoid valve 72 for selectively passing compressed air from the first solenoid valve 71 side to the cylinder 34 side and releasing compressed air supplied to the cylinder 34 to the atmosphere in S2; The first connecting to the gas supply passage 33 from the outlet of the valve 72
It comprises a gas flow path 73, a pressure sensor 74 for detecting the pressure in the accumulator 71, and a sub-control unit 75 for controlling the operation of a pump 66 via a motor 65 by pressure signals PH and PL from the pressure sensor 74. . Here, the main control unit 55 sends a control signal CS2 to the second solenoid valve 72 based on the pressure signal PL from the pressure sensor 74, and controls the operation of the second solenoid valve 72.

The secondary gas supply system 62 includes an inflator 77 for generating high-pressure combustion gas by igniting an explosive.
And a second gas passage 78 for guiding the high-pressure gas generated by the inflator 77 to the gas supply pipe 33.

The operation of the seat belt pretensioner mechanism 27 described above will now be described. FIG. 5 is an operation diagram illustrating the operation of the seatbelt pretensioner mechanism according to the present invention from immediately before the vehicle collision to the time of the vehicle collision. Immediately before the vehicle collision, the main control unit 55 sends the vehicle speed signal VS sent from the vehicle speed sensor 53 at the time of braking performed to avoid the collision, and the pedal sent from the brake pedal depression speed sensor 51 by the braking. It is determined whether each of the depression speed signal PV and the pedal depression amount signal PA sent from the brake pedal depression amount sensor 52 satisfies a braking condition for avoiding a collision.

When each of the signals VS, PV, PA satisfies the braking condition for avoiding a collision, the main control unit 55 sends a control signal CS1 to the first solenoid valve 71, and the first solenoid valve 71 Is switched from the closed state to the open state. Then, the compressed air stored in the accumulator 68 is supplied from the first electromagnetic valve 71 and the second electromagnetic valve 72 in the open state to the first gas flow path 7 as indicated by a white arrow.
3 and into the cylinder 34 of the operating section 30.

In the event of a vehicle collision immediately after braking for avoiding a collision, the vehicle body acceleration sensor 54 detects a sudden change in vehicle body acceleration and
5 to the vehicle body acceleration signal AS. As a result, the main control unit 55 sends the firing signal BS to the inflator 77. The inflator 77 is provided with the ignition signal BS.
As a result, the explosive is ignited and rapidly burns to generate high-pressure gas, which is sent into the cylinder 34 of the operating unit 30 as indicated by the black arrow.

That is, the primary gas supply system 61 is operated,
Next, the secondary gas supply system 62 is operated. As a result,
The piston 35 and the rack 36 in the cylinder 34 move downward, the pinion 37 rotates, and the winding shaft 31 shown in FIG. 3A rotates to wind the webbing 16.

In addition, separately from the above, when a collision occurs without stepping on the brake pedal, the main control unit 55 outputs a vehicle acceleration signal AS sent from the vehicle acceleration sensor 54 which detects a sudden change in vehicle acceleration. Based on this, both the primary gas supply system 61 and the secondary gas supply system 62 are operated almost simultaneously, and the piston 35 and the rack 3
With the downward movement of the webbing 6, the winding shaft 31
Wind up 6.

FIG. 6 is an operation diagram for explaining the operation of the seat belt pretensioner mechanism according to the present invention at the time of collision avoidance. After the braking for avoiding the collision described with reference to FIG.
4, that is, when the collision is avoided, the main control unit 55 determines that the vehicle body acceleration signal AS suddenly increases within a predetermined time after the braking, for example, within a predetermined time from when the foot is released from the brake pedal. To determine if it has changed.

When the vehicle acceleration signal AS does not change rapidly within a predetermined time, the main control unit 55 determines that collision has been avoided and activates the primary gas supply system 61. Without operating the secondary gas supply system 62, first, the control signal CS1 is sent to the first solenoid valve 71 to close the first solenoid valve 71, and then the control signal CS2 is sent to the second solenoid valve 72. Then, the second solenoid valve 72 is switched from the open state to the atmosphere open state, and the compressed air in the cylinder 34 is released to the atmosphere.

Accordingly, the pressure in the cylinder 34 decreases,
The piston 34 and the rack 36 are provided with a return spring 42.
3A, the pinion 37 rotates clockwise, and the winding shaft 31 shown in FIG.
Pull out 6.

FIG. 7 is an operation diagram for explaining the operation of the seat belt pretensioner mechanism according to the present invention when the accumulator is pressed. Each time the compressed air stored in the accumulator 68 is released, the pressure in the accumulator 68 decreases. When the pressure falls below a predetermined lower pressure limit, the pressure sensor 74 outputs a pressure signal PL to the main control unit 55. Send to sub-control unit 75.

Thus, the main control unit 55 switches the second solenoid valve 72 from the open-to-atmosphere state to the open state, and the sub-control unit 75 sends the motor drive signal DS to the motor 65. As a result, the motor 65 operates to drive the pump 66, and the pump 66
To start accumulating pressure in the accumulator 68 via.

When the pressure in the accumulator 68 reaches a predetermined upper pressure limit, the pressure sensor 74 sends a pressure signal PH to the sub-control unit 75. Thereby, the sub control unit 75 sends the motor stop signal SS to the motor 65. As a result, the motor 65 stops, the pump 66 stops, and the accumulation of pressure in the accumulator 68 ends.

As described above, by providing the return spring 42 and the second solenoid valve 72, the cylinder 34
The position of the piston 35 once moved is returned to the original position while the internal pressure is reduced.
And the provision of the pressure sensor 74, the accumulator 6
Since compressed air can always be stored in the primary gas supply system 8, after collision is avoided by braking, the primary gas supply system 6
1 can be operated repeatedly.

FIG. 8 is an explanatory diagram for explaining changes in the restraint state of the occupant by the seat belt pretensioner mechanism according to the present invention, together with the vehicle state. During normal traveling, the seat belt pretensioner mechanism does not operate, and the occupant is hardly restrained by the seat belt 10.

When braking for avoiding collision is performed, the primary gas supply system operates to draw the webbing 16 into the ELR section 26 as indicated by the white arrow, and the waist belt 1
The looseness of the shoulder belt 6a and the shoulder belt 16b is instantaneously removed and tightened to restrain the occupant. Thereafter, the ELR unit 26 is locked.

At the time of the collision following the braking operation, in addition to the retraction of the webbing 16 as indicated by the white arrow due to the operation of the primary gas supply system, the operation of the secondary gas supply system further increases the black arrow. Webbing 16 like
Is pulled in, and the occupant is further restrained.

FIG. 9 is a first flowchart illustrating the operation of the seat belt pretensioner mechanism according to the present invention, and FIG. 10 is a second flowchart illustrating the operation of the seat belt pretensioner mechanism according to the present invention. Represents a step number. (Refer to FIG. 4 for symbols) ST01: It is determined whether or not the brake pedal is depressed. If the brake pedal is not depressed (NO),
The process proceeds to ST12 shown in FIG. 10 via C2. If the brake pedal is depressed (YES), the process proceeds to ST02. ST02: It is determined whether the brake pedal depression speed detection value S2 detected by the brake pedal depression speed sensor 51 is larger than a predetermined brake pedal depression speed S1 as a threshold value. If S2> S1 is not satisfied (NO), ST01 is executed again. S2> S1 (YE
If S), proceed to ST03.

ST03: It is determined whether or not the brake pedal depression amount detection value L2 detected by the brake pedal depression amount sensor 52 is larger than a predetermined brake pedal depression amount L1 as a threshold value. Not L2> L1 (NO)
If so, ST01 is executed again. If L2> L1 (YES), the process proceeds to ST04.

ST04: It is determined whether or not the detected vehicle speed V2 detected by the vehicle speed sensor 53 is larger than a predetermined vehicle speed V1 as a threshold value. If V2> V1 is not satisfied (NO), ST01 is executed again. V2> V1 (YE
If S), proceed to ST05. ST05: The first and second solenoid valves 71 and 72 are opened and the first
The next gas supply system 61 is operated to tension the seat belt.

ST06: It is determined whether or not the detected vehicle body acceleration value α2 detected by the vehicle body acceleration sensor 54 is larger than a predetermined vehicle body acceleration value α1 as a threshold value. α2> α1
If not (NO), the process proceeds to ST07. If α2> α1 (YES), the process proceeds to ST11.

ST07: The first solenoid valve 71 is closed, then the second solenoid valve 72 is opened to the atmosphere, and the operation of the primary gas supply system 61 is released. Thereafter, the process proceeds to ST08. S
T08: The second electromagnetic valve 72 is closed, the pump 66 is driven by the motor 65, and the pressure is accumulated in the accumulator 68 again.

ST09: Pressure P in accumulator 68
AC has reached the upper pressure limit PUP, that is, PAC = PU
P is determined. If PAC is not PUP (NO), the process returns to ST08. If PAC = PUP (YES), the process proceeds to ST10.

ST10: The motor 65 and the pump 66 are stopped, the accumulation of pressure in the accumulator 68 is terminated, and the process returns to ST01 in FIG. 9 via C4. ST11: The inflator 77 is ignited to generate high-pressure gas, and the secondary gas supply system 62 is operated to tension the seat belt.

ST12: It is determined whether the detected vehicle body acceleration value α2 detected by the vehicle body acceleration sensor 54 is larger than a predetermined vehicle body acceleration value α1. If α2> α1 is not satisfied (NO), the process returns to ST01 of FIG. 9 via C3. α2> α1
If (YES), the process proceeds to ST13 and ST14. ST13: The inflator 77 is ignited, and the secondary gas supply system 62 is operated. ST14: The first and second solenoid valves 71 and 72 are opened, and the first
The next gas supply system 61 is operated.

As described with reference to FIGS. 4 to 8, the present invention supplies the compressed air or the high-pressure gas to the cylinder 34 immediately before a vehicle collision or the like to move the piston 35 at a high speed so that the seat can be moved. In the seat belt pretensioner mechanism 27 for tensioning the belt 10, the seat belt pretensioner mechanism 27 includes a pump 66 and an accumulator 6 for storing compressed air produced by the pump 66.
8. A primary gas supply system 61 comprising first and second solenoid valves 71 and 72 for supplying / stopping the compressed air stored in the accumulator 68 to the cylinder 34, and a high-pressure gas generated by the ignition of the inflator 77 to the cylinder The primary gas supply system 61 is operated first based on the vehicle speed, the stepping speed of the brake pedal, and the stepping amount of the brake pedal. And a main control unit 55 for operating the gas supply system 62.

As a result, since the compressed air is used as the driving source of the piston 35 in the primary gas supply system 61, the seat belt 10 can be tensioned at an earlier timing before the collision and the occupant restraint performance is improved. be able to.

Further, it is possible to determine the braking aimed at avoiding the collision from the vehicle speed, the stepping speed of the brake pedal and the stepping amount of the brake pedal, and the seat belt 10 is tensioned by the braking during the normal running other than the collision avoidance. Can be prevented.

[0053]

According to the present invention, the following effects are exhibited by the above configuration. The seat belt pretensioner mechanism of claim 1 is
A seat belt pretensioner mechanism is constituted by a primary gas supply system including a pump, an accumulator for storing compressed air produced by the pump, an electromagnetic valve for supplying / stopping the compressed air stored in the accumulator to the cylinder, and an inflator ignition. Based on the secondary gas supply system for supplying the generated high-pressure gas to the cylinder, the vehicle speed, the brake pedal depression speed, and the brake pedal depression amount, the primary gas supply system is operated, and if necessary, Next, the second
And a control unit that activates the secondary gas supply system.
Since compressed air is used as a driving source for the piston in the primary gas supply system, the seat belt can be tensioned at an earlier timing before the collision.

Further, it is possible to determine braking aimed at collision avoidance based on the vehicle speed, brake pedal depressing speed, and brake pedal depressing amount. Can be prevented. Further, after the collision is avoided, the compressed air can be stored again in the accumulator, and the primary gas supply system can be repeatedly operated.

In the seat belt pretensioner mechanism of the second aspect, when the control unit determines that collision has been avoided after activating the primary gas supply system, the control unit does not operate the secondary gas supply system. The piston has a control function of returning the piston to the original position by releasing the compressed air in the cylinder to the atmosphere, and repeatedly operating the primary gas supply system. The gas supply system can be repeatedly operated, and the replacement cost can be reduced as compared with, for example, replacing a gas supply system of a type used up once.

According to a third aspect of the present invention, there is provided a seat belt pretensioning method comprising: determining whether a stepping speed, a stepping amount, and a vehicle speed of a brake pedal exceed respective threshold values when the brake pedal is depressed; When the stepping speed, the stepping amount, and the vehicle speed respectively exceed the threshold values, the braking is determined to be the braking for collision avoidance, and the compression stored in the accumulator in the cylinder driving the seat belt winding means. A step of retracting the seatbelt by sending air to restrain the occupant instantaneously, a step of determining whether or not the vehicle body acceleration exceeds a threshold value, and a step in which the vehicle collides when the vehicle body acceleration exceeds the threshold value. The inflator is ignited, and the generated high-pressure combustion gas is sent into the cylinder to produce the above-described sheet. In addition to the retraction of the belt, further retraction of the seat belt is performed to further restrain the occupant, so that the occupant is restrained not only immediately after the collision but also immediately before the collision, and the occupant can be restrained from an earlier timing. Can be restrained and the occupant can be restrained in two stages, and the performance of restraining the occupant in the event of a collision can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a seat belt provided with a seat belt pretensioner mechanism according to the present invention.

FIG. 2 is a perspective view of an ELR with a pretensioner provided with a seat belt pretensioner mechanism according to the present invention.

FIG. 3 is a cross-sectional view of an ELR with a pretensioner provided with a seat belt pretensioner mechanism according to the present invention.

FIG. 4 is a configuration diagram of a seat belt pretensioner mechanism according to the present invention.

FIG. 5 is an operation diagram illustrating the operation of the seatbelt pretensioner mechanism according to the present invention from immediately before the vehicle collision to the time of the vehicle collision;

FIG. 6 is an operation diagram illustrating an operation of the seat belt pretensioner mechanism according to the present invention when collision is avoided.

FIG. 7 is an operation diagram illustrating the operation of the seat belt pretensioner mechanism according to the present invention when the accumulator is pressed.

FIG. 8 is an explanatory diagram illustrating a change in the restraint state of the occupant by the seat belt pretensioner mechanism according to the present invention, together with a vehicle state.

FIG. 9 is a first flowchart illustrating the operation of the seatbelt pretensioner mechanism according to the present invention.

FIG. 10 is a second flowchart illustrating the operation of the seat belt pretensioner mechanism according to the present invention.

[Explanation of symbols]

10: Seat belt, 13: Seat belt winding means (emergency lock type winding device with seat belt pretensioner), 27: Seat belt pretensioner mechanism, 34 ...
Cylinder, 35 piston, 55 control unit (main control unit), 61 primary gas supply system, 62
Secondary gas supply system, 66 pump, 68 accumulator, 71, 72 solenoid valve (first solenoid valve, second solenoid valve),
77: inflator, L1, S1, V1, α1: threshold value (predetermined value of brake pedal depression amount, predetermined value of brake pedal depression speed, predetermined vehicle speed, predetermined value of vehicle body acceleration), L
2: Brake pedal depression amount detection value, S2: Brake pedal depression speed detection value, V2: Vehicle speed detection value, α2: Body acceleration detection value.

Claims (3)

[Claims] 1. A seat belt pretensioner mechanism for supplying compressed air or high-pressure combustion gas to a cylinder immediately before and immediately after a vehicle collision and moving a piston at a high speed to tension a seat belt. The belt pretensioner mechanism includes a pump, an accumulator for storing compressed air produced by the pump, and a cylinder for supplying compressed air stored in the accumulator to the cylinder.
A primary gas supply system including a solenoid valve that stops, a secondary gas supply system that supplies the high-pressure combustion gas generated by inflator ignition to the cylinder, a vehicle speed, a brake pedal depression speed, and a brake pedal depression. A seat belt pretensioner mechanism comprising: a control unit that first activates the primary gas supply system and, if necessary, then activates the secondary gas supply system based on the amount. 2. When the control unit determines that collision has been avoided after activating the primary gas supply system, the control unit does not operate the secondary gas supply system and controls the compression in the cylinder. 2. The seat belt pretensioner mechanism according to claim 1, further comprising a control function of returning the piston to an original position by discharging air to the atmosphere and repeatedly operating a primary gas supply system. 3. A step of judging whether or not a stepping speed, a stepping amount and a vehicle speed of the brake pedal exceed respective threshold values when the brake pedal is depressed, wherein the stepping speed, the stepping amount and the vehicle speed of the brake pedal are respectively determined. When the threshold value is exceeded, the braking is determined as braking for avoiding collision, and the seat belt is retracted by sending the compressed air stored in the accumulator into the cylinder that drives the seat belt winding means. Instantaneously restraining the occupant, determining whether the vehicle acceleration exceeds the threshold, and determining that the vehicle has collided when the vehicle acceleration exceeds the threshold, igniting the inflator, By sending the generated high-pressure combustion gas into the cylinder, in addition to the seat belt retraction described above, a further seat belt is provided. A seat belt pretensioning method, wherein the occupant is restrained in two stages immediately before and immediately after the collision by retraction of the seat and further restraining the occupant.