JPH0382647A - Strap detecting device for air bag - Google Patents

Abstract

PURPOSE:To surely detect defective biting by providing a detecting sensor below the position where the folded section of the middle portion of a strap is properly arranged in a strap detecting device detecting the defective biting of the strap arranged inside when an air bag is folded. CONSTITUTION:A strap 4 for restricting the shape of an air bag 1 when it is deployed is connected to the gas inflow port periphery on its inner periphery and the opposite portion of a gas inflow port in the air bag 1 of the protective safety device of a vehicle, and its middle portion in the longitudinal direction is folded. A proximity switch 11 is buried at the position (proper arrangement position) where the folded section 4a of the middle portion in the longitudinal direction of the unbitten strap 4 is located in a working bed 9 of the strap detecting device of the air bag 1. A detecting jig 12 with a pressing rod 27 is removably fitted to a folding jig above the proximity switch 11. The distance between the proximity switch 11 and the detecting jig 12 is detected to judge defective biting.

Description

[Detailed Description of the Invention] <Industrial Application Field> This invention solves the problem of a strap being caught inside when folding an airbag that is attached to a steering wheel of an automobile and expands at a predetermined time. The present invention relates to an airbag strap detection device.

<Prior Art> In a conventional airbag, as shown in FIG. In order to regulate the shape when opened, it is known that a plurality of straps 4 are arranged to be connected to the periphery of the gas inlet 2 on the inner circumferential surface of the airbag l and to the opposing portion 3 of the gas inlet 2. (Refer to Utility Model Application No. 61-85549). Note that 7 is a retainer that connects the airbag 1 to the inflator 5 by fixing the peripheral edge of the gas inlet 2 of the airbag 1 to the flange 6 of the inflator 5 with a nut 8, and 7a is a retainer that is integrally attached to the retainer 7. The gas inlet 2 of the airbag 1 is formed in
This is a bolt that passes through the periphery and the flange portion 6 of the inflator 5 and is fastened with a nut 8.

Then, an airbag 1 with a strap 4 inside this
When folding the steering wheel so that it can be accommodated in a predetermined steering wheel pad, the following procedure is performed.

First, the retainer 7 is disposed around the periphery of the gas inlet 2, and the longitudinal intermediate portion of each strap 4 is folded so as to extend radially outward from the gas inlet 2, as shown in FIG. , the airbag 1 is set on a workbench 9 in a state in which the gas inlet 2 is disposed on the lower side and is expanded into a flat shape. In addition, the workbench 9 is formed with a fitting hole 9a into which the bolt 7a of the retainer 7 is fitted so as to fix the peripheral edge of the gas inlet 2 of the airbag 1.

If each strap 4 is caught between the retainer 7 and the periphery of the gas inlet 2, the airbag 1
Since the straps 4 do not expand to the desired shape, visually check whether each strap 4 is caught. This check shows that if the strap 4 is bitten, the bent portion 4a at the intermediate portion in the longitudinal direction of the strap shortens the distance from the gas inlet 2 and is placed closer to the gas inlet 2 than the predetermined placement position. For,
A check was made to ensure that the portion at the predetermined placement position was thinner due to the fact that the bent portion 4a was not placed.

After checking, a folding jig (not shown) is placed at a predetermined position on the airbag 1, and the airbag 1 is folded.

Note that when folding the airbag 1, as shown in FIG. 9, it is first folded into a long and narrow rectangular shape when viewed from above, and then folded from both sides as shown in FIG.

<Problems to be Solved by the Invention> However, in the past, the binding of the strap 4 was visually checked, which was time consuming and lacked stability. To provide an airbag strap detection device which solves the problem and can accurately and easily check the failure of strap biting when folding an airbag without relying on human visual observation. is the goal.

Means for Solving the Problems> The airbag strap detection device according to the present invention has an assembly member disposed around the gas inlet on the inner circumferential surface of the airbag, and a gas flow on the inner circumferential surface of the airbag. A longitudinally intermediate portion of a strap for controlling the shape of the airbag when it is expanded, which is connected to the inlet periphery and a portion facing the gas inlet, is folded so as to extend radially outward from the gas inlet, and When the airbag is set on a workbench in a state in which the gas inlet is placed on the lower side and deployed flatly, and then a folding jig is placed on the airbag to fold the airbag, the straps are folded. An airbag strap detection device for detecting a defective biting by the assembly member, the airbag strap detection device being arranged on the upper surface of the workbench below a position where a bent part of an intermediate portion of the strap is properly arranged. a detection sensor that is removably attached to the folding jig, a detection jig that is disposed above the detection sensor and that presses the airbag at a lower end; a control opening that detects the distance between the detection sensor and the lower end of the pressing rod based on the detection sensor and displays a predetermined display when the distance is within a predetermined range or outside the predetermined range, respectively. Special <Operations and Effects of the Invention> In the strap detection device according to the present invention, the airbag is set on the workbench, the folding jig is placed on the airbag, and then the detection jig is attached to the folding jig. .

Then, the pressing rod of the detection jig presses the airbag above the detection sensor on the workbench, and the control section detects the distance between the detection sensor and the lower end of the pressing rod.

At this time, the detection sensor and the lower end of the pressing rod are arranged at positions where the bent portion at the middle portion of the strap is properly arranged without being caught in the strap. Therefore, if the bent part of the strap is placed at the appropriate position, the distance between the detection sensor and the lower end of the pressing rod will be longer by the bent part, and if it is within the allowable range. , the control section displays OK by lighting a blue lamp or sounding a small buzzer, for example. Additionally, if the strap is caught between the assembly member and the periphery of the gas inlet of the airbag, the bent part of the strap will shift from its proper placement position to the gas inlet side, causing the detection sensor and pressure Since the distance from the lower end of the rod is shortened due to the absence of the bending part and is outside of the above-mentioned allowable range, the control unit may, for example, turn on a red lamp or use a large buzzer. NG (No GOOD) will be displayed, such as by making a sound.

If the control unit displays OK, the detection jig may be removed from the folding jig and the airbag may be folded using the folding jig. If the control unit displays NG, remove the detection jig from the folding jig, remove the folding jig from the airbag, remove the airbag from the workbench, and tighten the internal strap. cure congestion,
After that, all you have to do is set the airbag on the workbench again and "detect" the proper position of the bent part of the strap.

As described above, the strap detection device according to the present invention has the following features:
After setting the airbag on the workbench used for folding the airbag and placing the folding jig on the airbag, you can detect a strap that is not caught properly by simply attaching the detection jig to the folding jig. Embodiment An embodiment of the present invention will be described below with reference to the drawings.

Note that the same members as those in the prior art are given the same reference numerals and their explanations will be omitted.

As shown in FIG. 6, the strap detection device M of the embodiment includes a proximity switch 11 as a detection sensor arranged on a workbench 9, and a detection jig 12 detachably attached to a plate-shaped folding jig 10. and a control unit 13 disposed on the side of the workbench 9.

The proximity switch 11 is configured so that when the airbag 1 without the strap 4 is set on the workbench 9 as shown in FIGS. They are buried in four locations on the top surface of the workbench 9 at the placement positions (appropriate placement positions). Each of these proximity switches 11 is electrically connected to the control P4m13.The detection jig 12 is connected to the base 2 as shown in FIGS. 3 and 4.
1 and mounting plates 25 fixed to both ends of the base 21.

The base 21 holds a movable plate 24 that can move up and down, and the lower surface of the movable plate 24 has two positioning pins 24 that are respectively fitted into positioning holes 10a drilled in the folding jig 1o.
A is provided protrudingly. Further, the movable plate 24 is urged to be separated from the base 21 with the interposition of two compression coil springs 23, and is connected to the base 21 in such a way that it cannot be removed and is movable up and down. The separation distance from the base 21 is regulated by two guide rods 22 fixed to the base 21 .

Note that 21a fits the positioning pin 24a of the movable plate 24 into the positioning hole 10a of the folding jig 10, and
When detecting the placement position of the strap 4 by holding down the detection jig 12, a base 21 is provided that abuts against the airbag 1 to prevent a pressing rod 27, which will be described later, from sinking too much into the airbag 1.
This is a stopper that protrudes from the top. Further, 21b is a handle that holds the detection jig 12 during detection.

Each mounting plate 25 has a positioning pin 24a in the positioning hole 1.
0a and press the detection jig 12, the workbench 9
so that they are respectively arranged above the proximity switches 11 of
Two metal pressing rods 27 are provided.

As shown in FIG. 6, the two pressing rods 27 on each mounting plate 25 are such that one pressing rod 27A detects the placement position of the strap 4 on the right side of the airbag 1, and the other pressing rod 27B detects the placement position of the strap 4 on the right side of the airbag 1. is for detecting the placement position of the strap 4 on the left side of the airbag 1.

These pressing rods 27 have a large diameter part 27a at the lower end, a large diameter part 27b provided at the upper end through which the mounting plate 25 is inserted,
A compression coil spring 26 is interposed between the large diameter portion 27a and the mounting plate 25, and is constantly biased downward (see FIG. 3).

In the case of the embodiment, each mounting plate 25 has a pressing rod 2 corresponding to the length of the strap 4 of each type of airbag 1.
The hole through which the pressing rod 27 is inserted allows the pressing rod 27 to be moved in the radial direction around the gas inlet 2 of the airbag 1 when the strap 4 is detected. , about 4 in the longitudinal direction of the base 21
The elongated holes 25a and 25b extend in the direction of 5 degrees.

The control unit 13 inputs an electrical signal from each proximity switch 11 according to the distance from the lower end of the pressing rod 27, compares the electrical signal with a predetermined value, and determines whether the electrical signal is within an acceptable range (OK range) or acceptable. A predetermined electrical signal is output to the display section 31 depending on whether the signal is outside the range (NG range). The display unit 31 includes a blue lamp 32 that displays an OK range and a buzzer 33 that makes a small sound, and a red lamp 34 that displays an NG range and a buzzer 35 that makes a loud sound.

In the case of the embodiment, the control unit 13 is always in a conductive state with each proximity switch 11, and when the pressing rod 27 is pushed down, both of the lower ends of the pressing rod 27 are in the measurement capability range (first range) of the proximity switch 11.・Approximately 1 second after entering the range (combined OK range and NG range in Figure 2), compare the electrical signals from each proximity switch 11 with a predetermined value, and if any one of them is in the NG range outputs an electric signal that lights up the red lamp 34 on the display section 31 and activates the buzzer 35 for a predetermined period of time, and when both are within the OK range, lights up the blue lamp 32 on the display section 31 and outputs an electric signal that turns on the buzzer 35. Buzzer 3
3 is configured to output an electric signal for a predetermined period of time.

Next, the operation of folding the airbag 1 using the device M of the embodiment will be explained.

First, the retainer 7 is placed around the periphery of the gas inlet 2, and the intermediate portions of the four straps 4 in the longitudinal direction are folded so as to extend outward in the radial direction from the gas inlet 2.
As shown in FIG. 5, the airbag 1 is set on the workbench 9 in a state in which it is expanded into a flat plate with the gas inlet 2 located on the lower side. The bolts 7a of the retainer 7 passing through the circumference of the gas inlet 2 of the airbag 1 are fitted into the matching holes 9a for positioning. In addition, in the case of the embodiment, a suction means (not shown) is disposed on the workbench 9, and after the airbag 1 is set on the workbench 9, a suction means is provided to make the airbag 1 into a flat shape so that it can be easily folded. It is configured such that the air inside the airbag 1 can be sucked through the gas inlet 2 using a means.

After the air inside the airbag 1 is sucked using a suction means (not shown), the plate-shaped folding jig 10 is placed on the airbag 1 at a predetermined position. The positioning pin 24 is inserted into the positioning hole 10a of
a are fitted, and the detection jig 12 is placed on one of the folding jig 10 and pushed down. At that time, as shown in FIGS. 1 and 2, the lower ends of the two pressing rods 27 are both connected to the proximity switch 1.
A predetermined proximity switch 1 indicates that it has entered the measurement capability range of 1.
1, the control unit 13 compares the electric signals manually input from each nearby switch 11 with a predetermined value one second later, and if any one of them is within the NG range, it lights a red lamp 34 on the display unit 31. An electric signal for lighting and activating the buzzer 35 is output for a predetermined period of time. Moreover, when both are within the OK range, the control section 13 outputs an electric signal for lighting the blue lamp 32 of the display section 31 and operating the buzzer 33 for a predetermined period of time.

If the display unit 31 shows an NG indication, remove the detection jig 12 from the folding jig 10, remove the folding jig 10 from the airbag 1, and then remove the airbag 1 from the workbench 9 to remove the inside. After the strap 4 is fixed, the airbag 1 is set on the workbench 9 again, and the proper position of the bent portion 4a of the strap 4 is detected as described above.

Further, when the display section 31 displays an OK message, the detection jig 12 is transferred to the folding jig 10 on the left side and pushed down. Then, as mentioned above, the control unit 1 to which the predetermined electrical signal is input
3 compares the electric signal input from each proximity switch 11 with a predetermined value one second later, and outputs the predetermined electric signal to the display section 31 for a predetermined period of time.

If the display unit 31 shows NG, remove the airbag 1 from the workbench 9, fix the jamming of the strap 4, set it on the workbench 9 again, and set the right folding jig 1.
The detection jig 12 is placed at 0, and the detection work is restarted from the beginning.

Also, at this time, if the display unit 31 displays OK,
Since the straps 4 are not caught in this airbag 1, the detection jig 12 is removed from the folding jig 10, and the airbag 1 is started to be folded using the folding jig 10.

Note that both the lower ends of the pressing rods 27 are connected to the proximity switch 1
1, and when the lower end of any one of the pressing rods 27 is not within the measuring capability range when comparing the electric signal approximately 1 second later with a predetermined value. , no discrimination is made and the display section 31 does not display anything. Therefore, in that case, the settings are made again in the same way as in the case of NG display.

When folding the airbag 1, in addition to the folding jig 10, a predetermined number of horizontal folding bars 41 are provided at the base of each folding jig 10 and used by sequentially folding them down from the inside. This is done by using a predetermined number of vertical folding bars 42 which are arranged on the front side of the stand 9 and are used by sequentially folding them down from the inside. By the way, to explain the work, after making the first crease using the folding jig 10, each horizontal folding bar 41 is sequentially folded down from the inside, and the folded horizontal folding bar 41 is used as a guide as shown in FIG. Fold the airbag 1 horizontally as shown in . After that, each vertical folding bar 42 is sequentially folded down by an inner force 16, and the first vertical folding bar 42 is used as a guide.
Fold the airbag 1 vertically as shown in Figure 0. after that,
Remove the vertical folding bars 41, 42 and folding jig 10 from the airbag 1 of each machine, remove the airbag 1 from the workbench 9,
A predetermined inflator 5 may be attached to the airbag 1.

Therefore, the strap detection device M of the embodiment is set on the workbench 9 used when folding the airbag, and after placing the folding jig 10 on the airbag 1,
By simply attaching the strap 2 to the folding jig 1o, it is possible to detect a bad biting of the strap 4, and it is possible to check for a biting defect more accurately and easily compared to the conventional visual inspection method.

In addition, in the strap detection device M of the embodiment, the detection jig 1
Each of the pressing rods 27 of 2 is connected to each elongated hole 25a of the mounting plate 25.
It is held movably within 5b so that its position can be changed, and even if the length of the strap 4 changes due to different types of airbags 1, it can be easily handled. .

In the device M of the embodiment, the detection device 12 is shown to be used by being transferred to each folding jig 10, but the detection device 12 is approximately cross-shaped when viewed from above, and the four cross-shaped A configuration may also be adopted in which a pressing rod 27 is disposed at each tip of each strap so that the proper placement position of the bent portion 4a of each strap 4 can be detected by using it - times.

[Brief explanation of drawings]

FIG. 1 is a partial cross-sectional view showing a strap detecting device according to an embodiment of the present invention, in which the bent portion of the strap is placed at an appropriate position. FIG. FIG. 3 is a front view showing the detection jig of the same embodiment. FIG. 4 is a plan view showing the detection jig of the same embodiment. Figure 5 is a plan view showing the airbag set on the workbench of the same embodiment, and Figure 6 is a plan view showing the detection jig placed on the folding jig of the same embodiment. Plan view, Figure 7 is a cross-sectional view showing the airbag in an expanded state, Figure 8 is a cross-sectional view showing the airbag set on a workbench, and Figure 9 is a cross-sectional view showing the airbag when it is folded horizontally. FIG. 10 is a plan view and a front view showing the airbag in a vertically folded state. DESCRIPTION OF SYMBOLS 1...Airbag, 2...Gas inlet, 3...Opposing part, 4...Strap, 4a...Bending point, 7...(Assembly member) retainer, 9... - Workbench, 10... Folding jig, 11... (Detection sensor) proximity switch, 12... Detection jig, 13... Control unit, 27... Pressing rod, 31... Display Part, M... Strap detection device. Patent application Toyota Gokai Co., Ltd. Figure 7

Claims (1)

[Claims] An assembly member is disposed around the gas inlet on the inner peripheral surface of the airbag, and is connected to the peripheral edge of the gas inlet on the inner peripheral surface of the airbag and a portion facing the gas inlet. A longitudinally intermediate portion of the strap for regulating the shape when the airbag is expanded is folded so as to extend radially outward from the gas inlet, and the gas inlet is placed on the lower side and unfolded into a flat shape. When the airbag is set on a workbench in the state of The strap detection device includes a detection sensor disposed on the upper surface of the workbench below a position where the folded portion of the intermediate portion of the strap is properly arranged, and a detection sensor detachably attached to the folding jig. a detection jig equipped with a pressing rod attached above the detection sensor and pressing the airbag at a lower end; and detecting a distance between the detection sensor and the lower end of the pressing rod based on a signal from the detection sensor. What is claimed is: 1. An airbag strap detection device comprising: a control section that displays a predetermined display when the strap is within a predetermined range and when the strap is outside the predetermined range;