JPS5811338B2 - air bag device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides electrical front sensors, mechanical sensors,
Notify and warn the driver of the status of the pressure detection device, etc.
The present invention also relates to an airbag device that records these operating states.

More specifically, in an airbag device that includes an electric activation device that activates the airbag in the event of a vehicle collision, a sensor such as a mechanical sensor, a pressure detection device, etc., the pseudo activation of the sensor and the time lapse are detected. The present invention relates to an airbag device that reports and warns occupants of the resulting pressure drop in a gas generator, sensor failure, etc., and records the information.

As is already known, a vehicle's airbag system detects the impact of a car collision, and if the impact exceeds a set value, it activates a gas generator, thereby inflating the stored airbag. , reduce the impact on passengers,
This improves vehicle safety.

Such an airbag device includes an airbag, a gas generator, a starting means, an impact detecting means, and the like.

The impact detection means in such airbag devices mainly consists of an electric front sensor attached to the front end of the vehicle, a mechanical sensor inside the vehicle, etc., and is mainly operated using the vehicle battery. In an electric circuit wired inside the vehicle, the sensor detects a sudden impact during a collision, and performs a switching action to activate the activation means and activate the airbag device.

However, since the above-mentioned sensor has a mechanical structure, its set state may become incomplete as it ages. It is necessary to be aware of this abnormal state and to make it the best possible state.

Furthermore, it is necessary to notify the occupants of failures such as short circuits and disconnections in the electrical circuits from the viewpoint of safety in order to ensure reliable operation of the airbag device.

Furthermore, the gas pressure of the gas generator must always satisfy the set value in order for the airbag to fully inflate, so if the gas pressure becomes low due to natural gas leakage, etc. Also inform the crew.

In particular, it is extremely important to alert the occupants by informing them of the status of sensors, gas pressure, and wiring circuits, and at the same time to keep records of the above conditions after a collision occurs and use this later to improve the safety of the airbag system. That's true.

The inventor of the present invention has devised the present invention in order to further improve safety in view of the necessity required for the operation control device of the above-mentioned airbag device.

The object of the present invention is to detect an abnormal condition from each part of an electric front sensor, a mechanical sensor, a pressure detection device, a starting device, and an electric wiring circuit, notify the occupant of the abnormal condition, and simultaneously record this condition. To provide an airbag device capable of

Therefore, an object of the present invention is to enable the airbag system to operate safely and completely at all times by allowing the occupant to confirm the above-mentioned abnormal condition and replace the gas generator, repair the sensor, etc. To provide an airbag device in which an operating device of the device can be kept optimal.

Another object of the present invention is to use a memory element such as a core memory to record the above-mentioned abnormal conditions.
To provide an airbag device that allows checking the cause of activation or failure of a nib bag device after a collision occurs.

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

This will reveal further objects and advantages of the invention.

Fig. 1 is a schematic explanatory diagram of an airbag device in which the present invention is implemented, Fig. 2 is an explanatory diagram of the front part of a vehicle showing the layout of an embodiment in which the airbag device is provided on the driver's seat side, and Fig. 3 is an explanatory diagram of the front of the vehicle. Figure 4 is a vertical cross-sectional view of the electric front sensor, Figure 4 is a vertical cross-sectional view of the solenoid operated by the electric front sensor, Figure 6 is a diagram showing the pressure detection means, and Figure 5 is a vertical cross-sectional view of the mechanical sensor. be.

First, an outline of an airbag device to which the present invention is applied will be explained with reference to FIGS. 1 and 2. A is a vehicle, and an electric front sensor B is mounted on the body side of a mounting base 2 of a bumper 1 at the front of the vehicle. The installed high-speed solenoid C, which is activated when sensor B detects an impact of a predetermined value or more, is energized, and the connected mechanical valve opening device is opened. An inert gas, mainly nitrogen gas or argon gas, is regulated to a required pressure history and is supplied through the steering column G to the bag I attached to the bundle H, which is then inflated.

The mechanical valve opening device is also activated by a mechanical sensor J and a starting means attached thereto, and operates independently of B, C, and J, respectively, in the event that the electric front sensor B breaks down. This compensation causes the valve opening device to open, thus providing dual detection and activation means.

The electric front sensor B, the high-speed solenoid C1, the mechanical valve opening device, and the mechanical sensor J are connected to the fault display device L1 and the recording device M via the fault diagnosis device K, and these pieces of information are stored by the fault diagnosis device K. If a malfunction or incorrect operation based on this is detected, a warning is given to the occupants via the display device, and if the warning is ignored and the vehicle continues to be used,
and recording device M if a collision occurs after the gas pressure has decreased.
Which one is recorded in ?

In FIG. 3, reference numeral 3 denotes a housing for an electric front sensor, which is attached to the front of the vehicle via bolts 4 and a bracket 4a, and a piston-shaped weight 6 is slidably fitted into an internal cylinder 5. The weight 6 is made of nickel silver or the like, and its outer periphery is insulated with a coating 6a of Teflon or the like to ensure sliding within the cylinder 5.

The weight 6 is pressed by the preset spring 7 against the bottom cover 5a side of the cylinder 5, which is the left end in the figure, and the weight 6 is normally in contact with seating detection contacts 8a and 8b provided on the bottom cover 5a at the left end in the figure at the rear end. , detects that the user is seated.

On the other hand, the weight 6 has an axial hole 6b with a female tapered portion 6c at the front, and the periphery of the hole 6b is plated with a conductive metal to form a contact portion.

On the other hand, a guide element 9 is provided at the front part (right side in the figure), and the base of the guide element 9 is supported by a holder 9a, and the guide element 9 and the holder 9a are formed of an insulator.

The outer periphery of the guide element 9 is provided with a claw-shaped contact 10 split radially in the circumferential direction, and the base of this contact 10 has a ridge end attached to a filler 9b interposed between the holder 9a and the base of the guide element 9. These are connected to the supported cord 10a.
It is connected to a high speed solenoid C, which will be described in detail later, via a.

Further, the seating detection contacts 8a and 8b are connected to a fault diagnosis device K via a cord 9.

Furthermore, an insulating holder 11 and a filler material 12 such as urethane are interposed between the cylinder 5 and the housing 3.

The figure shows the time of collision detection, the weight 6 in the cylinder 5 moves forward against the spring 7, and the contact point 10 and the taper hole 6b
abutting and conducting between the contacts 10, which causes a signal to be transmitted to the solenoid C via the cord 10a, activating the mechanical valve opening device.

In the solenoid C that starts the opening and closing of the high-pressure gas generation container F shown in FIG.
A core 34 is internally fixed inside the sleeve 33a of No. 3, and the coil 32 is connected to the contact 10 of the front sensor B described above via a lead wire 35.

A space 36a is provided at the front end of the core 34 via a spacer 36, and a ring-shaped cylinder member 37 made of a magnetic material is provided at the front end of the space 36a, and a movable disc 38 made of a magnetic material slides into the cylinder hole 37a of this. It is fitted so that it can move freely.

The rod 38a of the movable disk 38 is connected to the front wall 31a of the case 31.
Projects outward and is associated with the valve opening device.

The back surface of the main body 36c connected to the base of the rod 38a of the movable disc 38 is removed in a conical shape to form a recess 38b,
The weight of the disk 38 has been reduced and the movement of the core 34 during energized suction has been made faster.

The edge-like edge of the movable disk 38 in the rod direction is normally attracted to a position separated from the core 34 by a magnet 40 via a non-magnetic spacer washer 39, and is connected to a valve opening device.

When the contact 10 is made conductive by the collision detection by the sensor B, the coil 32 is energized and excited, and this causes the disc 38 to be attracted to the end surface 34a of the core 34, and the rod 38a to move to the right.
Release the valve opening device and open the high pressure gas container F.

FIG. 5 shows a mechanical sensor J, in which the main body 80 is a cylinder 8.
1, the axis of the cylinder 81 is arranged horizontally, and a piston-shaped weight 82 is slidably fitted inside.

The outer periphery of the intermediate portion of the weight 82 is provided with an axially long groove 83, and a spring 84 is provided between the front surface of the weight 82 and the front wall 81a of the cylinder 81 to press it rearward.
is compressed, and the rear end of the weight 82 is normally connected to the cylinder 8.
1, the contact 85 is closed, and this information is transmitted to the fault diagnosis circuit K, display L, and recording device M.

At the bottom of the main body 80, there is a cavity 8 that communicates with a part of the cylinder 81.
0a is provided, and a detection orbit arm 86 is pivotally mounted within this space 80a with a pin 87.

The arm 86 includes an arm portion 86a that engages with the groove 83 of the weight 82, a weight portion 86b that biases the weight 82 to the normal position in normal times, and an engagement arm portion 86c that is related to the valve opening device.

FIG. 5 shows a normal state, in which the arm portion 86a is abutted against and supported by the left shoulder 83a of the groove 83, and rotation in the counterclockwise direction in the figure is restricted.

At the time of a collision, if the impact is greater than the level that causes damage to the occupant, the weight 82 slides forward against the spring 84 due to the impact load.

The preload of the spring 84 is determined based on the load at the time of collision.

As the weight 82 moves forward, the arm portion 86b moves toward the right shoulder 8 of the groove 83.
3b, thereby causing the arm 86 to rotate counterclockwise in the figure, releasing the engagement of the engagement arm portion 86b that restrains the valve opening device, opening and closing it, and activating the airbag.

FIG. 6 shows a valve opening device, and 60 is a housing for the valve opening device, and above the housing in the figure (in front of the vehicle body), two gas container bodies 40 described above are arranged in parallel 40A.

40B, and therefore the support portion comprises two pieces 42A, 42B.

Rods 45A and 45B that support the sealing plate 43 and guide plate 44 of each main body and close the openings protrude from the chamber 61 in the housing 60, and FIG. 6 shows the timing state in the valve open state.

The solenoid C1 mechanical sensor J described above is integrated into the housing.

The ends of each rod 45A, 45B are engaged and supported on one end of each of pieces 62, 63, and the bottom of this end of piece 62, 63 engages pieces 64, 65 at an offset position, and piece 64 , 65 are engaged with and supported by the wall 61a of the chamber 61.

Opposite ends of the pieces 62, 63 are ramped and supported below by one end of the intermediate piece 66, one end of the piece 66 is also supported in engagement with the wall 61a by an offset piece 67, which further supports the piece 66. The other end is final piece 6
A piece 69 is offset and supported by one end of the sensor piece 8, and this piece 69 engages with the same end of a sensor piece 70 whose one end is supported by the wall 61a.

Each of the above-mentioned engagements is merely a contact engagement and can be disassembled by disengaging the sensor piece 70 by the solenoid C1 mechanical sensor J.

A part of the combined load of the pieces acts on the sensor piece 70 as a force in the counterclockwise direction in the figure, and this is applied to the sensor piece 70 by the spring 7.
Bimetal 71 supported by adjustment screw 72 with 2a inside
The contact 73 is opened by the upward movement of the bimetal 71 due to the decrease in gas pressure, which takes out a signal and sends it to the fault diagnosis device K, display L, and recording device M, warning that the gas pressure is below the specified value. do.

In FIG. 7, thick lines indicate the electric actuating circuit shown in solid lines in FIG. 1, and thin lines indicate the fault diagnosis circuit shown in broken lines.

In the figure, the upper and lower B and B are diagrams of the left and right electric front sensors installed at the front end of the vehicle.
are weights, which are in contact with the seating detection contacts 8a and 8b, respectively, and are in a normal state.

At the time of collision, weight 6.6 slides to the left and contacts 10, 10
short circuit.

The contacts 8b and 8b are connected to terminals 102 and 105 of a fault diagnosis module 106, that is, a fault diagnosis device, and a constant voltage is applied to these terminals 102 and 105 from a battery 107.

C indicates a solenoid, and the normal solenoid C includes a battery 107, a switch S1, a diode D1. D2, resistance R
A minute current is flowing through R1 and R2, but the solenoid C does not operate normally with this minute current.

The input and output terminals of the solenoid C are connected to terminals 100 and 101 of the module 106 by lead wires, respectively.

In this case as well, a constant voltage is applied to the terminals 100 and 101.

71 schematically shows a bimetallic switch section of a means for detecting a pressure drop in a high-pressure gas container.

Contact 73 is opened when the gas pressure decreases.

J is a mechanical sensor, and since the weight 82 is in the normal position, the contact 85 is closed.

One end of these 71°J is the terminal 103 of the module 106.
, 104, respectively, and the bent ends are grounded, so the terminals 103 and 104 are normally held at zero potential.

C1 is a capacitor that secures the power to operate solenoid C when the power circuit is disconnected in the event of a collision, and Dl prevents the electricity in the capacitor C1 from flowing back in the event of a short circuit in the battery 107, headlights, etc. in the event of a collision. A diode, D2. R3 prevents a large current from flowing into capacitor C1 when the power is turned on.

Terminals 108 to 113 of the module 106 are connected to various parts of the wiring circuit and are used to detect failures such as disconnection shoots, and a constant voltage is applied to them except for the terminal 110 which is grounded and has zero potential.

Moreover, a failure warning lamp 116 is installed between the terminals 114 and 115.
That is, the above-mentioned indicator is provided.

Failures in various parts of the electrical operating circuit shown in FIG. 7 are handled by module 106 via fault diagnostic circuit wiring.

Details of module 106 are discussed below.

FIG. 8 shows the circuit configuration inside the module 106.

The configuration and operation of this fault diagnosis module circuit will be explained.

The NAND circuit 1170 input has the already mentioned 100°101
．． Terminals 108, 109, 111, and 112 are connected.

Normally, a high voltage (Level) is applied to these terminals, so the transistor Tr1 is not made conductive through the NOR circuit 118 and the NAND circuit 119, and the terminal 114
, 115 does not light up either.

Even if one of the inputs of the NAND circuit 117 has a low voltage (
0 level), the NAND circuit outputs a level, which turns on the transistor TR1, and current flows from the power supply Vcc to light up the failure warning lamp 116, and the memory element 120 stores the warning lighting time of the lamp 116. do.

The input becomes 0 level at terminals 100, 101゜108
．． This occurs when a part of the electric operating circuit connected to the terminals 109, 111, and 112 is short-circuited or the power supply voltage drops.

The input of the NAND circuit 121 is connected to the electric front sensor B, the seating detection contact 8b of B, via the terminals 102 and 105.
Connected to 8b.

Normally, the weight 6.6 is set at the position shown in FIG. 7 by the preset spring 7, so the contact point 8
A and 8b are conductive, and 102 and 105 are in a level.

In this state, the output of the NAND circuit 121, the NO
The transistor Trl is not turned on via the R circuit 118 and the NAND circuit 119 to maintain a normal state.

Weight 6.6 causes spring 1 to stop due to the sudden stop of the vehicle, etc.
When the terminal 8at8b is turned off for a certain period of time by moving to the left in the figure against this, the input of the NAND circuit 121 becomes O level.

At this time, the transistor R is passed through the same circuit as above.
r1 is turned on, and the warning lamp 116 and lighting time storage element 120 are activated.

The terminal 110 is normally grounded and maintains the 0 level and maintains a normal state, but when the ground wire is disconnected and the potential increases, the transistor Tr1 is turned on via the NOR circuit 122 and the NAND circuit 119, and a warning is emitted from the lamp 116. , this is recorded by 120.

In the differential amplifier 123, one input 123a is connected to the power supply Vcc and takes the level, and the other input 123b
is grounded via the pressure detection means 71 and is at 0 level under normal conditions, so the output is level, and therefore NA
The transistor Tr1 is maintained in the off state via the ND circuit 119, and no warning is displayed.

When the pressure in the high-pressure gas container decreases and the contact 73 turns off, the input 123a of the differential amplifier 123 changes from 0 level to level, and in order to make the output of the differential amplifier 123 go to 0 level, Transistor T
r1 is turned on, a warning is issued by lamp 116, and this is recorded by 120.

In addition, the terminal 104 connected to the ground via the contact 85 of the mechanical sensor J maintains the 0 level in normal times, and if the weight 82 turns off the contact 85 due to a sudden stop of the vehicle, it becomes a level and the above-mentioned Similarly, the warning and warning recording operations are performed via the differential amplifier 123, the NAND circuit 119, and the transistor Tr1.

Electric front sensor B and mechanical sensor J mentioned above
The warning caused by the movement of the weight 6.82 occurs suddenly while driving the vehicle and is activated for a certain period of time, making it easy for the driver to confirm.

However, the springs 7.84 that elastically support the respective weights 6.82 have weakened over time, and warnings due to minute movements of the weights 6.82 that may occur due to this are short-lived and intermittent, making it difficult for the driver to It is also difficult to confirm.

For this purpose, the following circuit is provided.

The terminals 102 and 105 are connected to the input 12 of the differential amplifier 124 via the NAND circuit 121, and the terminal 104 is connected directly to the input 12 of the differential amplifier 124, respectively.
4b.

The other input 124a is maintained at a level by the power supply Vcc.

Electric sensor B, mechanical sensor J weight 6.8
2 maintains its normal position, the input 124b is at the 0 level, so the output of the differential amplifier 124 becomes a level, and no warning is displayed at this time.

When either the electric front sensor B or the mechanical sensor J momentarily changes the input 124b to level due to the above-mentioned cause, the monostable multivibrator 125 is activated and the
It becomes a level for a certain period of time.

During a certain period of time when the monostable multivibrator 125 takes the level, the self-propelled multivibrator 126 operates, and as a result of the operation of this 126, a blinking warning is issued by the lamp 116 via the NOR circuit 122 and the NAND circuit 119. Record this.

Airbag I deploys at the moment of collision, so
It is necessary to record the actual operation of the electric sensor B and the valve opening device 1, and the circuit of FIG. 7 also performs this recording.

127 is a core memory which can be magnetized by a line drawn out from the terminal 100, and this line is further grounded via a transistor Tr2 that performs a switching action.

The input 128a of the AND circuit 128 is the terminal 101, NOT
Since the circuit 129 is connected to the solenoid terminal via the monostable multivibrator 130, it is at a level under normal conditions, and becomes 0 level for a certain period of time only when the monostable multivibrator 130 is activated.

The above operation of the monostable multivibrator 130 is performed by instantaneous operation of the solenoid C at the time of a collision.

On the other hand, the input 128b of the AND circuit 128 is connected to the differential amplifier 1
31, its level is determined by the operation of the pressure sensing means 71, and the normal input 128b takes the 0 level.

Therefore, the output of the AND circuit 128 is at 0 level, the transistor Tr2 is not conductive, and the core memory 127 is not magnetized.

One input terminal 131a of the differential amplifier 131 is always connected to the power supply V
A constant voltage obtained by dividing Vcc is applied by cc,
The + input terminal 131b normally takes a zero level of zero potential.

Therefore, the output of the differential amplifier 131 is normally at 0 level,
When the pressure detection means 71 operates and 131b becomes a level, the output becomes a level and changes the state of the input 128b.

From the above, after the solenoid C operates, the valve opens and gas expands, and the airbag deploys to the pressure detection means 71.
Normal operation (12
8a is at O level and 128b is at level), the transistor Tr2 is not turned on and the data is not recorded in the core memory 127.

Conversely, before the solenoid C operates, a drop in gas pressure due to gas leakage in the high-pressure gas container is detected, or the valve opens due to the operation of the mechanical sensor J, causing the airbag ■ to deploy and the gas pressure to drop. Abnormal operation of detecting (128a)
128b), the transistor Tr2 is turned on, the core memory 127 is magnetized, and this abnormal operation is recorded.

The magnetizing current of the core memory 127 at this time is a minute current flowing through the solenoid C under normal conditions.

This record in the core memory 127 will remain even after the collision.

In case of normal operation as above, monostable multivibrator 13
0 becomes a write level after a certain period of time, but at this time the fuse 132 is blown by the operating current of the solenoid C and the charge of the capacitor C1 is also discharged, so the terminal 100 becomes zero potential and the magnetizing current in the core memory 127 is Since it does not occur, it is not recorded.

The operating power supply Vcc is the battery 10 connected to the terminal 113.
7 through a resistor, diode, and capacitor,
Use a slightly smaller voltage value.

FIG. 9 shows the configuration of the circuit inside the module shown in FIG.
This is another embodiment in which a record is left in the core memory 127 when the solenoid C operates to safely deploy the airbag.

In this case, the monostable multivibrator 130 is provided between the input 128b of the AND circuit 128 and the output of the differential amplifier 131.

This is assumed to be 130'.

When the gas pressure in the gas container F decreases and the output of the differential amplifier 131 reaches the level, the monostable multivibrator 130' operates to maintain the zero level for a certain period of time.

Therefore, in the case of normal operation (128a is a lebel and 128b is a lebel) after the solenoid C is activated, the valve is opened, gas expands, and the airbag is deployed, and the pressure detection means 71 detects a decrease in pressure and is activated. The AND circuit 128 outputs the rubel and records it in the core memory 127.

Conversely, before the solenoid C operates, the valve opens due to the operation of the mechanical sensor J, the airbag 1 deploys, and the gas pressure decreases.
8b is 0 level), it is not recorded in the core memory 127.

Furthermore, if a bistable multivibrator or the like is used instead of the monostable multivibrator 130', even in the case of natural leakage of high-pressure gas, when the pressure detection means 71 is activated, the input 128b changes from the level to 0 level, and this Since the 0 level is maintained, even if solenoid C is activated thereafter, it will not be recorded in core memory 127.

FIG. 10 shows a partial circuit of the circuit according to another embodiment, which records the back-and-forth relationship between the mechanical sensor J and the valve opening device.

The input 128b normally takes the 0 level, and when the valve opening device operates and the gas pressure decreases, it becomes a level.

The input 128a is connected to a monostable multivibrator 130'' and has a normal level, and becomes 0 level for a certain period of time only when the mechanical sensor J is activated.

Therefore, after the mechanical sensor J is activated, the valve opening device is activated by the mechanical sensor J, the airbag is deployed, and the pressure is reduced (128a is 0 level, 128b is the level), and the AND circuit 128 Since the output of is at 0 level and the transistor Tr2 is off, it is not recorded in the core memory 127.

On the other hand, before mechanical sensor J operates, solenoid C
The operation in which the valve opening device is activated first, the airbag is deployed, and the pressure is reduced due to the activation of the
28b is Lebel), the output of the AND circuit is Lebel, and the transistor Tr2 is turned on, so the core memory 12
7 is magnetized and recorded.

Here, the terminal 104 actually detects the start of movement of the mechanical sensor J, that is, the start of leftward movement of the weight 82 in FIG. 5, and does not detect the operation of the starting means C like the terminal 101.

Further, as in the case of the electric starting means, it goes without saying that the circuit can be constructed so as to record when the mechanical starting means operates before the valve opening device.

As is clear from the above description, according to the present invention, in order to ensure that the airbag device operates in the event of a vehicle collision, an electric front sensor and a mechanical Changes in the set state of electrical operating circuits and mechanical systems such as a type sensor, an electrical activation means for operating a valve opening device that inflates high-pressure gas, and a means for inflating an air bag and detecting the gas pressure in a high-pressure gas container. In addition to quickly reporting and warning the occupants, this information is recorded and the status of the airbag system can be checked at all times.

In particular, by keeping a record of the operating order of the electric starting means and the valve opening device or the operating order of the mechanical starting means and the valve opening device at the time of a collision using a memory element, it is possible to The activation sequence of the activation means can be clearly and reliably known after a collision, and this information can be used for subsequent research and research to further improve the reliable and safe operation of airbag devices, and to realize a simpler and cheaper circuit. I can do it,
This will greatly contribute to the widespread practical use of this type of safety device.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a systematic explanatory diagram of the system, FIG. 2 is a perspective explanatory diagram of the front of the vehicle, and FIG. 3 is an enlarged vertical sectional view of an electric sensor. Figure 4 is a vertical side view of the electric starting means, Figure 5 is a vertical side view of the mechanical sensor, Figure 6 is a cross-sectional plan view of the valve opening device, Figure 7 is the fault diagnosis circuit, and Figure 8 is the fault diagnosis. Internal Circuits of the Module FIGS. 9 and 10 are diagrams of another embodiment of the module circuit. In the drawings, A is a vehicle, B and C are electrical sensors and starting means, J and 86 are mechanical sensors and starting means, F, 19 and 40.
is a gas source, D, 60 to 68 are valve opening devices, K, 106 is a failure diagnosis device, L, 116 is a display device, M, 120, 12
7 is a recording device.

Claims (1)

[Claims] 1 It has both a mechanical sensor and an electric sensor for detecting a collision, and their activation device, and in the event of a collision, the detection operation of at least one of the above sensors operates the valve opening device, and high pressure gas is generated from the high pressure gas container. In an airbag system for a vehicle that inflates a bag, each detecting means detects each operating state of a gas pressure, a mechanical sensor, an electric sensor, and a starting device, and a diagnosis in which signals from the each detecting means are inputted. A diagnostic device comprising a circuit and a recording device, the diagnostic circuit having a circuit that can record on the recording device so that the activation order of the mechanical and electrical sensor systems at the time of a collision becomes clear. An airbag device featuring: