JPH1035408A - Side air bag controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accomplish compactification of a structure and improvement of control precision in a side air bag controller controlling an action of a side air bag. SOLUTION: In each of a left center pillar and a right center pillar, an ECU controlling an action of a side air bag device is arranged respectively. A substrate of an ECU 14 is formed into two-layer structure consisting of a first substrate 112 arranged on a vehicle width directional outside and a second substrate 114 arranged on the vehicle width directional inside. Both of an electric acceleration sensor 74 and a mechanical acceleration sensor 62, which detect acceleration working on the vehicle, are mounted on the first substrate 112. If acceleration higher than the predetermined value is detected in both of the electric acceleration sensor 74 and the mechanical acceleration sensor 62, a side air bag is expanded by means of a control circuit which is formed of the first substrate 112 and the second substrate 114.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a side airbag control device, and more particularly to a side airbag control device suitable for controlling the operation of a side airbag mounted on a vehicle.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Utility Model Laid-Open Publication No. 1-17995.
No. 7, and Japanese Utility Model Application Laid-Open No. 6-1035 discloses a side airbag. The side airbag is a safety device provided to absorb energy input from the side of the vehicle. The side airbag is housed at the side of a seat or the like, and when energy exceeding a predetermined value is input to the vehicle from the side, the side airbag expands to absorb the energy.

[0003] Energy input from the side of the vehicle reaches the vehicle interior in a shorter time than energy input from the front of the vehicle. Therefore, the side airbag system is required to have higher responsiveness than an airbag for absorbing energy input from the front of the vehicle (hereinafter, this airbag is referred to as a front airbag). In order to ensure high responsiveness in the airbag system, it is effective to detect the magnitude of the input energy in the vicinity of the part where the energy is input.

The above-described conventional side airbag system is an electric type that detects acceleration in a vehicle width direction inside a closed section of a rocker or center pillar on the right side of the vehicle and inside a closed section of a rocker or center pillar on the left side of the vehicle. Acceleration sensor. As described above, when the acceleration sensors are disposed on the left and right side surfaces of the vehicle, the magnitude of the energy input from the right side of the vehicle and the magnitude of the energy input from the left side of the vehicle are improved. It is possible to detect with high accuracy under the responsiveness. Therefore,
According to the above-described conventional side airbag system, the side airbag can be operated with high responsiveness.

[0005]

The signal output from the acceleration sensor is generally a weak signal that is easily affected by noise. For this reason, it is desirable that the acceleration sensor and the control circuit that processes the signal of the acceleration sensor are close to each other. Therefore, when the acceleration sensors are disposed on each of the left and right sides of the vehicle, the control circuit for the right side airbag and the control circuit for the left side airbag are separately configured,
It is desirable to arrange them inside the locker or center pillar on the right side of the vehicle and inside the locker or center pillar on the left side of the vehicle, respectively.

The output signal of the electric acceleration sensor may be affected by noise. For this reason, in the case where the acceleration acting on the vehicle is detected only by the electric acceleration sensor as in the conventional system described above, when noise is superimposed on the output signal of the acceleration sensor, the magnitude of the acceleration is erroneously detected. May be Therefore, in order to prevent malfunction of the side airbag, it is desirable to use both an electric acceleration sensor and a mechanical acceleration sensor.

In order to satisfy the above two requirements, control devices for controlling the operation of the left and right side airbags are separately provided, and each control device includes an electric acceleration sensor and a mechanical acceleration sensor. , Control circuit and built-in,
In addition, it is necessary to arrange these control circuits in a closed section such as a locker or a center pillar on the right side of the vehicle and in a closed section such as a locker or a center pillar on the left side of the vehicle.

However, a large space cannot be secured inside the closed section of the locker or the center pillar. Therefore, in order to store the above-described control device (that is, a control device having an electric acceleration sensor, a mechanical acceleration sensor, and a control circuit having a built-in control circuit) in such a space, the control device must be appropriately miniaturized. Need to be applied.

Further, when the acceleration acting on the vehicle is detected by both the electric acceleration sensor and the mechanical acceleration sensor, the acceleration having substantially the same phase acts on both acceleration sensors. That is, it is necessary to consider that the energy input to the vehicle reaches both the acceleration sensors following substantially the same transmission path.

The present invention has been made in view of the above points, and has a small physique, and an electric acceleration sensor and a mechanical acceleration sensor substantially reduce the acceleration acting on a vehicle. An object of the present invention is to provide a side airbag control device that performs detection in the same phase and under excellent responsiveness.

[0011]

The above object is achieved by the present invention.
A side airbag control device disposed inside a structural member on a side surface of a vehicle, wherein a first substrate disposed outside in a vehicle width direction is electrically connected to the first substrate. And a second substrate disposed on the inner side in the vehicle width direction, and an electric acceleration sensor disposed on the first substrate,
A mechanical acceleration sensor disposed on the first substrate; and accelerations formed on the first substrate and the second substrate, the acceleration exceeding a predetermined value in both the electric acceleration sensor and the mechanical acceleration sensor. And a control circuit for expanding the side airbag when it is detected.

In the present invention, the components required for the side airbag control device are mounted separately on a first substrate and a second substrate. Therefore, downsizing of the side airbag control device is realized. The side airbag control device includes both an electric acceleration sensor and a mechanical acceleration sensor. Therefore, malfunction of the side airbag caused by electric noise is prevented. In addition, the side airbag control device includes a control circuit in addition to the electric acceleration sensor and the mechanical acceleration sensor. Further, the electric acceleration sensor and the mechanical acceleration sensor are both mounted on a first substrate disposed outside in the vehicle width direction. According to the above configuration,
The influence of the energy input from the side of the vehicle is transmitted directly and substantially in the same phase to the electric acceleration sensor and the mechanical acceleration sensor, and the output signal of the electric acceleration sensor becomes noise. It reaches the control circuit without significant influence. Therefore, high detection accuracy is realized for the input of energy from the side of the vehicle.

[0013]

FIG. 1 is a system configuration diagram of a side airbag system according to an embodiment of the present invention. The side airbag system of this embodiment includes a battery 10. As shown in FIG. 1, a battery 10 is connected to a right electronic control unit 14 via a junction box 12.
(Hereinafter, referred to as the right ECU 14).

The right ECU 14 is housed inside a center pillar 16 on the right side of the vehicle. The right ECU 14 includes a left electronic control unit 18 (hereinafter, a left ECU 18).
) Are connected. The left ECU 18 is housed inside a center pillar 20 on the left side of the vehicle.

[0015] The side airbag system of the present embodiment comprises:
A right side airbag module 22 is provided. The right side airbag module 22 includes the right front seat 2
4 is stored near the right lumbar support. The right side airbag module 22 includes a side airbag folded to a predetermined size, an inflator for supplying inflation gas to the side airbag, and a squib for igniting the inflator when a predetermined current is supplied. . The squib provided in the right side airbag module 22 is connected to the right ECU 14.

The side airbag system of this embodiment is
A left side airbag module 26 is provided. The left side airbag module 26 includes the left front seat 2
8 is stored near the left lumbar support. The left side airbag module 26 includes a side airbag folded to a predetermined size, an inflator that supplies inflation gas to the side airbag, and a squib that ignites the inflator when a predetermined current is supplied. . The squib provided in the left side airbag module 26 is connected to the left ECU 18.

FIG. 2 is a block diagram showing the electrical configuration of the side airbag system according to the present embodiment. As shown in FIG. 2, the right ECU 14 includes a Tc terminal 30. The right ECU 14 and the left ECU 18 have a function of detecting an abnormality that has occurred during operation. Further, the right ECU 14 has a function of storing a code corresponding to an abnormality detected by the right ECU 14 and the left ECU 18. When the Tc terminal 30 is grounded, the code stored in the right ECU 14 can be read.

The right ECU 14 has an SLa terminal 32. A warning lamp 34 is connected to the SLa terminal 32.
Is connected. The warning lamp 34 is supplied with electric power from the battery 10. Right ECU14
Indicates that the self-abnormality is detected and that the left ECU 2
When the abnormality signal is transmitted from the second, the warning lamp 34 is turned on to notify the driver of the abnormality of the system.

The right ECU 14 has an Acc terminal 36 and an IG terminal 38. The Acc terminal 36 is connected to a positive terminal of the battery 10 via a switch 42 which is a component of the IG switch 40. The IG terminal 38 is connected to the switch 4 which is a component of the IG switch 40.
4 is connected to the positive terminal of the battery 10.

The right ECU 14 has an FR + terminal 46 and an FR- terminal 48. FR + terminal 14 and F
The R-terminals 48 are connected to both ends of a squib 50 built in the right side airbag module, respectively.
Further, the right ECU 14 includes an E1 terminal 52 and an E2 terminal 54. E1 terminal 52 and E2 terminal 54
Are both body earthed.

The Acc terminals 36 and I of the right ECU 14
The G terminal 38 is connected to the booster circuit 56. The booster circuit 56 is a circuit that outputs a voltage of about 15 V when a battery voltage is supplied to its input terminal. The booster circuit 56 is provided to secure a voltage required for operating the system when the battery voltage drops. The output terminal of the booster circuit 56 is connected to the Vreg line 58.

The ignition circuit 60 is connected to the Vreg line 58. The ignition circuit 60 is constituted by an FET element. The Vreg line 58 is connected to the drain terminal of the ignition circuit 60. The source terminal of the ignition circuit 60 is connected to the squib 50 via the FR + terminal 46.

The right ECU 14 has a safing sensor 62 connected to the FR-terminal 48. The safing sensor 62 is a mechanical acceleration sensor. The safing sensor 62 is turned on when an acceleration exceeding a predetermined value acts on the right ECU 14 in a predetermined direction.

The safety sensor 62 includes a safety circuit 6
4 are connected. The safety circuit 64 is constituted by an FET element. The safing sensor 62 is connected to the drain terminal of the safety circuit 64. The source terminal of the safety circuit 64 is connected to the Gnd line 66. G
The nd line 66 is body-grounded via the E1 terminal 52 and the E2 terminal 54.

A backup capacitor 68 is connected to the Vreg line 58. The backup capacitor 68 stores electric charge until the inter-electrode voltage becomes Vreg while the drive voltage Vreg is being output from the booster circuit 56.
The electric charge stored in the backup capacitor 68 stops the power supply from the battery 10 to the right ECU 14,
Also, when the side airbag needs to be activated, it is discharged to the Vreg line 58.

The Vreg line 58 has a 5V power supply IC 70
Is connected. The 5V power supply IC 70
This is a constant voltage source that reduces the drive voltage Vreg output from the controller to 5 V and outputs it. The output voltage of the 5V power supply IC 70 is supplied to the microcomputer 72 and the electric acceleration sensor 74.
Is supplied to

A gate terminal of the ignition circuit 60 and a gate terminal of the safety circuit 64 are connected to the microcomputer 72. The microcomputer 72 includes:
An output signal of the electric acceleration sensor 74 is supplied.
The electric acceleration sensor 74 outputs a signal corresponding to the magnitude of the acceleration acting on the right ECU 14 (hereinafter, this signal is referred to as an acceleration signal). Microcomputer 72
Receives a signal from the electric acceleration sensor 74 and performs a predetermined calculation. When the calculation result exceeds a preset threshold value (predetermined value), the ignition circuit 60 and the safety circuit 6
4 is turned on.

The right ECU 14 is provided with the electric acceleration sensor 7.
4 and a safing sensor 62 are provided inside the center pillar 16 so as to detect acceleration in the vehicle width direction. Therefore, when large energy is input to the vehicle from the right side, both the ignition circuit 60 and the safety circuit 64 are turned on, and the safing sensor 62 is also turned on. When the ignition circuit 60, the safety circuit 64, and the safing sensor 62 are all turned on, the drive voltage Vreg is applied to both ends of the squib 50. When the drive voltage Vreg is applied to the squib 50, the inflator of the right side airbag module is ignited, and the right side airbag expands.

The right ECU 14 has an EEPOM 76 connected to the microcomputer 72. EEP
The ROM 76 is a nonvolatile memory capable of erasing stored contents by supplying an electric signal. The microcomputer 72 writes into the EEPROM 76 data to be stored even after the power supply to the microcomputer 72 is stopped, such as a code corresponding to an abnormality detected by the right ECU 14 or the left ECU 18.

The right ECU 14 has a Vreg terminal 78 connected to the Vreg line 58, a communication terminal 80 connected to the microcomputer 72, and a Gnd terminal 82 connected to the Gnd line 66. Right ECU1
4 is a Vreg terminal 78, a communication terminal 80, and
It is connected to the left ECU 18 via a Gnd terminal 82.

The left ECU 18 is connected to the right ECU 1
4 Vreg terminal 78, communication terminal 80 or Gnd terminal 8
2 is provided with a Vreg terminal 84, a communication terminal 86, and a Gnd terminal 86, which are connected to the terminal 2. The Vreg terminal 84
It is connected to the Vreg line 90.

The ignition circuit 92 is connected to the Vreg line 90. The ignition circuit 92 is constituted by an FET element. Vreg line 90 is connected to the drain terminal of ignition circuit 92. The source terminal of the ignition circuit 92 is connected to the FL + terminal 94. FL + terminal 94
Is connected to one end of a squib 96 incorporated in the left side airbag module 26. The other end of the squib 96 is connected to an FL-terminal 98 provided in the left ECU 18.
It is connected to the.

A safing sensor 100, which is a mechanical acceleration sensor, is connected to the FL-terminal 98. The safing sensor 100 is turned on when an acceleration exceeding a predetermined value acts on the left ECU 18 in a predetermined direction. The safety circuit 102 is connected to the safing sensor 100. The safety circuit 102 is constituted by an FET element. The safing sensor 100
It is connected to the drain terminal of the safety circuit 102. The source terminal of the safety circuit 102 is grounded to the Gnd line of the left ECU 18.

The Vreg line 90 has a 5V power supply IC 10
4 are connected. 5V power supply IC 104 is the right EC
Drive voltage Vre supplied from U14 to Vreg line 90
It is a constant voltage source that reduces g to 5V and outputs it. The output voltage of the 5V power supply IC 104 is
6 and the electric acceleration sensor 108.

The microcomputer 106 is connected to the gate terminal of the ignition circuit 92 and the gate terminal of the safety circuit 102. The microcomputer 106
Is supplied with an output signal of the electric acceleration sensor 108. The electric acceleration sensor 108 is connected to the left ECU 18
And outputs an acceleration signal corresponding to the magnitude of the acceleration acting on. The microcomputer 106 performs a predetermined operation in response to a signal from the electric acceleration sensor 108, and when the operation result exceeds a preset threshold value (predetermined value), the ignition circuit 92 and the safety circuit 102 Is turned on.

The left ECU 18 is provided with the electric acceleration sensor 1
08 and the safing sensor 100 are arranged inside the center pillar 20 so as to detect acceleration in the vehicle width direction. Therefore, when large energy is input to the vehicle from the left side, the ignition circuit 92 and the safety circuit 102
Are turned on, and the safing sensor 10
0 is also turned on. Ignition circuit 92, safety circuit 102,
When all the safing sensors 100 are turned on, the drive voltage Vreg is applied to both ends of the squib 96. When the drive voltage Vreg is applied to the squib 96, the inflator of the left side airbag module is ignited, and the left side airbag expands.

As described above, in the system of the present embodiment, the right side EC for controlling the operation of the left and right side airbags.
The U14 and the left ECU 18 each include a control circuit including electric acceleration sensors 74 and 108, safing sensors 62 and 100 as mechanical acceleration sensors, and microcomputers 72 and 106.
Further, as described above, the right ECU 14 and the left ECU 1
8 is stored in a small space inside the center pillars 16 and 20.

In this embodiment, the right ECU 14 and the left E
The point that the CU 18 is small enough to be accommodated inside the center pillars 16 and 20 and that the electric acceleration sensors 74 and 108 and the safing sensors 62 and 100 detect acceleration without time lag. Is characterized by the fact that Hereinafter, with reference to FIGS. 3 to 5, a characteristic portion of the present embodiment will be described.

FIG. 3 is a plan view of the substrate 110 after various elements, connectors and the like are mounted. The substrate 110 is
The ECU 14 is common to the right ECU 14 and the left ECU 18. In the following description, it is assumed that the board 110 shown in FIG.

The printed board 110 includes a first board 112,
A second substrate 114 and a wire harness 116 are provided. The first substrate 112 and the second substrate 114
It has an appropriate bending rigidity. On the other hand, the wire harness 116 has flexibility. First substrate 112 and second substrate
The board 114 is electrically connected by a wire harness section 116.

The first substrate 112 has screw holes 118 to 124
It has. The electric acceleration sensor 74 and the safing sensor 62 are both mounted on the first substrate 112. The second substrate 114 has screw holes 126 to 132. The microcomputer 72 is provided on the second substrate 114.
And the like are mounted.

FIG. 4 is an exploded view of the right ECU 14.
The right ECU 14 includes a board 110, a housing 134, and a cover 136. The substrate 110 is shown in FIG.
As shown in (1), the first substrate 112 and the second substrate 114 are mounted in a folded state so as to face each other. First
The board 112 is screwed to the housing 134 by screw screws 138 to 144 inserted into the screw holes 118 to 124. On the other hand, the second substrate 114 has the screw holes 12
Screw 146 inserted in 6,132
8, and screwed to the housing 134 by screw screws 154 and 156 inserted into the screw holes 150 and 152 of the cover 136 and the screw holes 128 and 130 of the second substrate 114.

The cover 136 is made up of the housing 13 by the screw screws 154 and 156 described above and the screw screws 162 and 164 inserted into the screw holes 158 and 160.
Screwed to 4. According to the above structure, the first substrate 112 on which the electric acceleration sensor 74 and the safing sensor 62 are mounted can be firmly fixed to the housing 134.

FIG. 5 is a sectional view of the right ECU 14.
As shown in FIG. 5, the right ECU 14 controls the center pillar 16 so that the first board 112 is located outside in the vehicle width direction, the second board 114 is located inside in the vehicle width direction, and the wire harness portion 116 is located above the vehicle. Is fixed to the outer panel 166.

The center pillar 16 is a part on which energy is directly applied when energy is input to the vehicle from the right side. When the right ECU 14 is housed inside the center pillar 16 in the posture shown in FIG. 5, the arrangement positions of the electric acceleration sensor 62 and the safing 74 are very close to the input point of the energy acting on the vehicle.
Therefore, when the right ECU 14 is mounted in the posture shown in FIG. 5, it becomes possible to detect the input of energy with extremely excellent responsiveness after the input of energy starts.

As in the present embodiment, both the electric acceleration sensor 62 and the safing sensor 74
12, the acceleration acting on the electric acceleration sensor 62 and the acceleration acting on the safing sensor 74 have the same acceleration with no phase difference. For this reason,
According to the system of the present embodiment, after the input of energy to the vehicle is started, the input of the energy is quickly and accurately detected by the electric acceleration sensor 62 and the safing sensor 74.
Can be detected by both.

In this embodiment, similarly to the first substrate 112, the second substrate 114 is screwed to the housing 134. On the first substrate 112, an electric acceleration sensor 62 and a safing sensor 74, which are easily affected by vibration, are mounted. Therefore, the first substrate 112
Need to be firmly fixed to the housing 134. On the other hand, on the second substrate 114, a structure that is easily affected by vibration is not mounted.

For this reason, the second substrate 114 does not necessarily need to be firmly fixed to the housing 134. Therefore,
The structure for fixing the second substrate 114 can be a simpler structure. If the structure for fixing the second substrate 114 is made simpler, the cost of the right ECU 14 can be further reduced.

In the above description, the right side E
The structure of the CU 14 and the effect obtained by adopting the structure are described.
The CU 18 has the same structure as the right ECU 14, and the same effect is obtained. Further, in the above embodiment, the right ECU 14 and the left ECU 18 are housed inside the center pillars 16 and 20, respectively. However, the present invention is not limited to this. It may be housed inside the left and right lockers or inside the left and right doors.

In the above embodiment, the center pillars 16 and 20 correspond to the "structural members on the side of the vehicle" according to the first aspect, and the safing sensors 62 and 100 correspond to the "mechanical acceleration" according to the first aspect. The "sensor" corresponds to the "control circuit" according to the first aspect of the present invention, wherein an electric circuit mainly constituted by the microcomputers 72 and 106 and configured inside the right ECU 14 or the left ECU 18 corresponds to the "control circuit".

[0051]

As described above, according to the present invention, a side airbag control device which is small in size, hardly affected by electric noise, and has high detection accuracy for energy input from the side of the vehicle is realized. can do.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a side airbag system according to an embodiment of the present invention.

FIG. 2 is a circuit diagram showing an electrical configuration of the side airbag system shown in FIG.

FIG. 3 is a development view of a board included in a right ECU used in the side airbag system shown in FIG. 1;

FIG. 4 is an exploded view of a right ECU used in the side airbag system shown in FIG.

FIG. 5 is a sectional view of a right ECU used in the side airbag system shown in FIG. 1;

[Explanation of symbols]

14 Right ECU 16,20 Center pillar 18 Left ECU 50,96 Squib 62,100 Safety sensor (mechanical acceleration sensor) 72,106 Microcomputer 74,108 Electric acceleration sensor 110 substrate 112 first substrate 114 second substrate 116 Wire harness part 134 Housing 136 Cover

Claims (1)

[Claims] 1. A side airbag control device disposed inside a structural member on a side surface of a vehicle, comprising: a first substrate disposed outside in a vehicle width direction; and a first substrate electrically connected to the first substrate. A second substrate disposed on the inner side in the vehicle width direction; an electric acceleration sensor disposed on the first substrate; a mechanical acceleration sensor disposed on the first substrate; A control circuit formed on the first substrate and the second substrate, for expanding the side airbag when acceleration exceeding a predetermined value is detected by both the electric acceleration sensor and the mechanical acceleration sensor; A side airbag control device, comprising: