JP2001334908A - Vehicular occupant protection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicular occupant protection system capable of preventing malfunction of an occupant protection mechanism to any failure if the failure is only one. SOLUTION: A squib module is provided with ignition switches 38 and 39 connected to a squib 39a in series. A communication control circuit 36 determines collision based on acceleration data transmitted from an ECU through a serial communication control bus and turns on the ignition switch 38 when the collision is determined. An acceleration level determination circuit 37 determines the collision based on the acceleration data from a G sensor module on the serial communication bus and turns on the ignition switch 39 when the collision is determined. The squib 39a is ignited only when both of the ignition switches 38 and 39 are turned on. Thus, the ignition of the squib 39a is prevented when only one of the ignition switches 38 or 39 is turned on and thereby the malfunction of the occupant protection system is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle occupant protection system.

2. Description of the Related Art Conventionally, as an occupant protection system for a vehicle, there is an air bag system as disclosed in Japanese Patent Application Laid-Open No. 10-154992. This airbag system is
An electronic control unit and a plurality of ignition circuits are connected to the same serial communication bus.

According to the above airbag system, the electronic control unit controls each ignition circuit using software via the same serial communication bus based on the detection output of the acceleration sensor. are doing. Therefore, even if the number of ignition circuits increases in the future, the electronic control device needs to be changed only by changing the software. However, for example, when the acceleration sensor erroneously detects and outputs a collision of the vehicle, the erroneous detection output is given to each ignition circuit by the same serial communication bus. Therefore, the ignition circuit may cause the airbag to malfunction. In addition, in the airbag system, if the electronic control unit has only one collision determination function, the airbag system can be similarly operated even when the collision determination function erroneously determines that the vehicle is in collision. May malfunction. In order to address the above, the present invention prevents a malfunction of the occupant protection mechanism in the vehicle occupant protection system, no matter what kind of fault occurs, if the fault is only one place. The purpose is to:

In order to solve the above-mentioned problems, a vehicle occupant protection system according to the first aspect of the present invention includes a plurality of occupant protection mechanisms, a plurality of accelerations mounted at different positions of a vehicle. Sensor module (20 to 20c), multiple squib modules (30 to 30g)
And an electronic control unit (10), and a serial communication bus (40) connecting each acceleration sensor module, each squib module, and the electronic control unit. In the vehicle occupant protection system, the plurality of acceleration sensor modules each include an acceleration sensor (21) for detecting the acceleration of the vehicle at different positions of the vehicle, and a detected acceleration of the acceleration sensor for a corresponding squib module. Transmission means (2) for transmitting acceleration data to the serial communication bus
3, 218). The electronic control unit determines whether there is a collision of the vehicle based on the acceleration data for the corresponding squib module on the serial communication bus, and transmits the determination result to the serial communication bus as the determination data for the corresponding squib module. Means (15, 16, 116). Further, each of the plurality of squib modules includes a squib (39a) driven when a corresponding occupant protection mechanism of the plurality of occupant protection mechanisms is operated, and a squib (39a) connected to the squib in series and turned on only when both are turned on. Both ignition switches (38, 39) for driving the squib and collision determination means (37) for judging the presence or absence of a vehicle collision based on acceleration data for the corresponding squib module on the serial communication bus and turning on one of the two ignition switches. ). The other ignition switch is turned on when the corresponding squib module determination data on the serial communication bus indicates a collision of the vehicle. As described above, since the squib is driven only when both ignition switches are turned on for each squib module, the squib is not driven when only one of the ignition switches is turned on. In other words, even if only one of the ignition switches is accidentally turned on due to a fault in the system,
Since the squib is not driven, malfunction of the occupant protection mechanism can be reliably prevented. In the invention according to claim 2,
The electronic control device according to the first aspect of the present invention includes an ignition command transmission unit (128) for transmitting an ignition command for a corresponding squib module to any of the plurality of squib modules to a serial communication bus, Receiving the ignition command for the corresponding squib module on the serial communication bus, and determining whether there is a collision of the vehicle based on the determination data for the corresponding squib module on the serial communication bus, and determining that there is a collision. It is characterized by including other collision determination means (321 to 324) for turning on the other ignition switch. As described above, the other collision determination means of the squib module determines the presence / absence of a collision based on the ignition command of the electronic control unit. A similar effect can be achieved. According to a third aspect of the present invention, in the vehicle occupant protection system according to the first or second aspect, the collision determination means of the electronic control unit transmits the corresponding squib module determination data to the corresponding squib module acceleration. The data is transmitted to the serial communication bus in a signal form different from data. Thereby, the collision determination means of each squib module can correctly determine the corresponding squib module determination data without mistaken for the corresponding squib module acceleration data. As a result, the operation and effect of the invention described in claim 1 or 2 can be more accurately achieved. According to the fourth aspect of the present invention, in the vehicle occupant protection system according to the third aspect, the signal form of the corresponding squib module determination data has a voltage amplitude different from that of the corresponding squib module acceleration data. It is characterized by being. Thereby, the function and effect of the invention described in claim 3 can be further improved. In the invention according to claim 5,
In the invention according to any one of claims 1 to 4,
The collision determination means of the electronic control unit is characterized in that the determination includes the type of collision of the vehicle. Thus, the determination by the collision determination means of the electronic control unit is performed in consideration of the type of collision, so that the function and effect of the invention according to any one of claims 2 to 4 can be achieved. In addition, the occupant protection mechanism can be operated in a state that matches the collision site of the vehicle and the state of acceleration. According to the invention described in claim 6, in the invention described in any one of claims 2 to 4, one of the two collision determination means of the plurality of squib modules includes a collision form of the vehicle. It is characterized by determining. Thus, one of the two collision determination means of each squib module is determined in consideration of the type of collision, so that the operation and effect of the invention according to any one of claims 2 to 4 can be achieved. Needless to say, the occupant protection mechanism can be operated in a state that matches the collision site of the vehicle and the state of acceleration. According to a seventh aspect of the present invention, in the vehicle occupant protection system according to any one of the second to fourth aspects, the electronic control unit may control each of the plurality of squib modules immediately after the start of the operation. One of the collision judging means includes an information transmitting means (104) for transmitting information for judging including the type of collision of the vehicle to the serial communication bus, and one of each of the collision judging means of the plurality of squib modules is The determination is made based on the information on the serial communication bus, including the type of collision of the vehicle. According to this, not only the same operation and effect as the invention described in claim 6 can be achieved, but also the information is transmitted to the serial communication bus by the information transmission means of the electronic control device. Even if the numbers of the squib modules and the acceleration sensor modules are changed, it is only necessary to change the information in the information transmitting means of the electronic control unit, and it is possible to easily and flexibly respond to the change of the system. In addition,
The reference numerals in parentheses of the above means indicate the correspondence with specific means described in the embodiments described later.

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
This will be described below. 1 and 2 show a passenger car according to the present invention.
1 illustrates one embodiment of an airbag system. This d
The baggage system includes an electronic control unit 10 (hereinafter referred to as E
CU10) and N acceleration sensor modules
(Hereinafter referred to as G sensor module) and M squibs
Module, ECU 10, each G sensor module and
Serial communication bus 4 connected between each squib module
0. In the present embodiment, N = 4 and four
G sensor module 20 to G sensor module
20c is employed. Also, when M = 8, eight scans are performed.
Squib modules 30 to 30 g
Has been adopted. Note that N = 1 to N = 4, respectively.
G sensor module 20 to G sensor module 2
0c. Also, M = 1 to M = 8, respectively.
Squib module 30 to squib module 30g
Corresponding to In addition, each squib module 30 to squib
The module 30g is provided at each position of the vehicle to be described later.
To operate each airbag mechanism separately.
is there. Each airbag mechanism is activated by its operation.
Deploy the airbag. The serial communication bus 40
It is composed of a ground line 41 and a power signal line 42.
Have been. The ground line 41 is connected to the ECU 10 and the G sensor model.
Joules 20 to 20c and squib modules 30 to
The ground terminal of each component of 30 g is grounded. Power signal line
The power supply 42 (not shown) in the ECU 10
G sensor modules 20 to 20c and each squib module
To 30 g to 30 g. In addition, the power signal
The in 42 is normally at the voltage a (V), and during communication,
The voltage is changed according to the digital signal (see FIG. 4).
The voltage range depends on the type of information, such as a diagnostic signal.
Is the voltage range A (ab) (V), and the acceleration data
Data and the like are in the voltage range B (ac) (V),
The fire command is in the voltage range C (ad) (V).
You. The ECU 10 controls the floor below the front wall of the passenger compartment of the passenger car.
It is provided at the center of the left and right sides of the surface (see FIG. 1). This EC
U10 is a driver receiver 11 as shown in FIG.
To 13, a data conversion circuit 14, and a communication control circuit 15
And a collision determination circuit 16. Each dora
The receivers 11 to 13 are connected to the power signal line 42 and
Interface circuit connected to the
Serves as a road. In addition, each driver receiver 1
Reference numerals 1 to 13 denote a power supply (not shown) and each component in the ECU 10.
Between the element and the G sensor modules 20 to 20c.
The power is supplied through the power signal line 42. Driverless
The signal in the voltage range A shown in FIG.
Signal, etc.) with the data conversion circuit 14 and the power supply signal line 42
Send and receive between The driver receiver 12 is shown in FIG.
Data conversion of signals (acceleration data, etc.) in the indicated voltage range B
Data is transmitted and received between the circuit 14 and the power signal line 42. Ma
The driver receiver 13 has a voltage range C shown in FIG.
Signal (ignition command, etc.) to the data conversion circuit 14 and the power supply
Transmission and reception are performed with the signal line 42. Data conversion circuit 1
4 is a communication control circuit 15 and each driver receiver 11 to
13 and the data conversion circuit 14
As for reception, each of the driver receivers 11 to 13
Communication control circuit by properly converting the sign of output data from
15 and bit error of the output data
Inspection is also performed. Further, the data conversion circuit 14
For communication, the address of the output from the communication control circuit 15
Message with a check bit added based on the command
To generate any one of the driver receivers 11 to 13
Output to The communication control circuit 15 includes the data conversion circuit 14
The communication is connected between the
The control circuit 15 is connected to the power signal line 42
Data change is performed for each of the G sensor modules 20 to 20c.
Through the conversion circuit 14 and each of the driver receivers 11 to 13
Acceleration data request, self-diagnosis request and ignition command
To the power signal line 42. And each of the above requests
If a response is received through the power signal line 42 to the
The communication control circuit 15 includes the driver receivers 11 to 13
And the response is received through the data conversion circuit 14,
Controls the overall communication of the airbag system. Also,
The communication control circuit 15 receives an input via the data conversion circuit 14.
Is output to the collision determination circuit 16, and the
Data indicating that there is a collision of the vehicle from the determination circuit 16;
Receiving the collision type information, generating an ignition command,
The data is output to the data conversion circuit 14. The communication control circuit 15 is mainly
A microcomputer is used as an element
12 to 15 with a microcomputer
Execute the program according to the flowchart shown
The above processing in the control circuit 15 is performed. In addition,
Each G sensor module is stored in the memory of the micro computer.
20-30c and each squib module 30-30
Each physical address, logical address, and expansion attribute that specifies g
And state information are stored in advance (see FIGS. 5 and 10).
See). The collision determination circuit 16 is a microcomputer.
The collision determination circuit 16 is connected to the power signal line 4
2, via the driver receiver 12 and the communication control circuit 15
At least two of the G sensor modules 20 to 20c
From the digital acceleration data sent from the
Based on the data, it is determined whether there is a collision of the car,
When judging a collision, the type of collision
The determination is made based on the data shown in FIGS.
The communication control circuit 15, the data conversion circuit 14, and the driver.
To the power signal line 42 through the receiver 13.
You. In the present embodiment, each development attribute in FIG.
Data shows the position of each squib module with respect to the car.
It is set in consideration of the acceleration characteristic according to the position. Both G
The sensor modules 20 and 20a are as shown in FIG.
Right and left inside the front bonnet of the car.
Each is fitted. Both G sensor modules 20b,
20c are mounted on the left and right of the floor of the passenger compartment of the passenger car, respectively.
Is being worn. Each G sensor module 20 to 20c
Are acceleration sensors 21 as shown in FIG.
(Hereinafter, referred to as a G sensor 21) and an AD converter 22.
, A communication control circuit 23, a data conversion circuit 24,
And receiver receivers 25 and 26.
The sensor modules 20 to 20c have the G sensor 21
The detected acceleration of A / D conversion is performed in response to a request from the ECU 10.
The digital signal is converted by the converter 22 and the communication control circuit 23
Data conversion circuit 24 and both driver receivers 25 and 26
A message is sent to the power signal line 42 through either of them.
To send. However, all the G sensor modules 20 to
When 20c transmits simultaneously, transmission is performed on the power signal line 42.
Since the communication signals collide, each G sensor module 20 through
20c started transmitting at different timing
I have. Here, each of the G sensor modules 20 to 20c
The G sensor 21 is provided for each G sensor module for the car.
The accelerations that occur at the positions where
Detected. The AD converter 22 detects the G sensor 21
Converts acceleration into digital data as acceleration digital data
Output to the communication control circuit 23. The communication control circuit 23
It operates according to the request of CU10.
The control circuit 23 basically transmits acceleration digital data.
Issue a self-diagnosis and send the result.
And do. This communication control circuit 23 includes main constituent elements
And equipped with a microcomputer, this microphone
The computer sends each of the above transmissions in the communication control circuit 23.
The timing control and the respective transmissions are shown in FIGS.
Execute the program according to the flowchart shown in
Do with. The memory of the microcomputer (see FIG. 7)
7), the physical addresses shown in FIG.
It is stored in advance. Note that this memory has
Address used only in the G sensor module
Is provided. Data change
The conversion circuit 24 is substantially the same as the data conversion circuit 14 of FIG.
The same processing is performed. Both driver receivers 25 and 26 are also
3 performs substantially the same processing as that of the driver receiver. What
Since the ignition command is not sent and received, the driver
No driver receiver corresponding to the sheaver 13 is required.
The squib modules 30 to 30g are as shown in FIG.
And each driver receiver 31 to 33 and both data conversion
Circuits 34 and 35, a communication control circuit 36, an acceleration level
A determination circuit 37, both normally open ignition switches 38 and 39,
And a squib 39a. Each driver receiver 31
33 are the driver receivers 11 to 13 of FIG.
Each is the same. Both data conversion circuits 34 and 35 are
3 is the same as the data conversion circuit 14 of FIG.
The circuit 34 includes a communication control circuit 36 and each driver receiver 3
1, 32, 33, and a data conversion circuit 35
Are the acceleration level determination circuit 37 and the driver receiver 33
Is connected between. The communication control circuit 36 includes an ECU
Driver receiver 32 and data conversion circuit 3 from 10
The ignition switch 38 is turned off in response to the ignition command via
Function and self-diagnosis in response to the self-diagnosis command.
It has a function to send out the diagnosis result. Communication control circuit
36 is a micro computer as its main constituent element.
Data with this microcomputer.
Therefore, according to the flowcharts shown in FIGS.
The communication control circuit 36 executes the program, and
The control of the output timing and the transmission are performed. Also communication
Memory of microcomputer memory of control circuit 36
In the area, a physical address as shown in FIG. 9 is stored in advance.
Have been. Further, the memory includes the squib module.
Logical addresses and airbags used only in
Another memory area for storing the open attribute (see FIG. 10)
Is secured. Note that, in FIG.
"1" indicates that the airbag is not deployed.
Represent. The acceleration level determination circuit 37 is a data conversion circuit 3
5 only receives the acceleration digital data and
When the value exceeds the predetermined acceleration level, the ignition switch 3
Turn 9 on. With the communication control circuit 36 thus configured,
In order to drive the squib 39a, both ignition switches 3
8 and 39 are both turned on. Also, the ignition switch 38
It is turned on in response to an ignition command from the ECU 10 and
The switch 39 controls the acceleration flowing through the power signal line 42.
Digital data is read by the acceleration level determination circuit 37.
Turns on when the detected acceleration exceeds a predetermined acceleration level.
Thus, the drive of the squib 39a is divided into two independent systems.
Therefore, if one system fails and the
Even if the fire switch is turned on, the squib 39a
Will not be ignited. The squib module 30
Actuates the passenger airbag mechanism of the passenger car,
Squib module 30a Airbag for driver's seat of the passenger car
Activate the squib mechanism and make each squib module 30b, 30d
Is the side airbag mechanism for the front and rear seats on the left side of the car.
Each is operated, and each squib module 30c, 30e
Are the airbag mechanisms for the front and rear seats on the right side of the passenger car.
The squib module 30f is moved to the left of the passenger car.
Activate the side curtain airbag mechanism and
30g of joule is the right curtain airbag of the car
Activate the mechanism. Next, the communication route in the present embodiment is described.
Will be described. This communication rule is master / thread
Be used. The airbag system is one master
And a plurality of slaves, and the slave is a master.
Will not work unless requested by Therefore, slave
Each other does not communicate on their own, but each slave
Even if there is no request from the master
Monitor all the above signals. The request from the master is specified
Slaves can be specified and requested without specifying slaves
Can be transmitted. In this airbag system, the master
Each slave is an ECU 10 and each G sensor module
20-30c and each squib module 30-30
g. In the airbag system, the master
-Three types of addresses to identify each slave,
That is, the physical address, logical address, and
You. The physical address is assigned to each of the G sensor modules 20 to 2
0c, each squib module 30 to 30g, etc.
Address given when the unit is manufactured at the parts factory
Logical address when starting up the airbag system.
Used to set. Each physical address is
Everything is different from each other. In addition, each physical address
Are standardized according to the module type and mounting position.
Is desirable. The logical address is
Used to identify the slave during normal mode of the system.
Address. Identification only within the airbag system
In general, the amount of information is greater than the physical address
Is less. Do not use physical addresses in normal mode.
The purpose is to improve communication efficiency. Deployment attributes
Is a squib module that can deploy each airbag
This deployment attribute is set for any passenger car.
Information that specifies whether to deploy in the event of such a collision
Then, depending on the type of collision, one ignition command
The purpose is to ignite multiple squibs (see FIG. 10).
See). In addition, each of the collision modes 1 to P is a collision site of a passenger car.
Large acceleration according to (position of each squib module)
Small, transmission speed and airbag (for each squib module
The degree of deployment of each airbag mechanism)
Identify. Communication control circuit 1 of ECU 10 as master
5 includes individual squib modules and each collision mode 1 in advance.
The expansion attribute (see FIG. 10) representing the relationship with
The data is stored in advance as set data. And master
The device transfers its information to the slave during the initial operation.
Accordingly, the slave, which is a squib module,
The information is stored, and this stored information is
Check with the collision type information sent with the fire command,
It is determined whether to drive the squib. Physical address
For example, to avoid a match with
Bit is set to 1 and the first bit of the expansion attribute is set to 0. Next
Next, the message format in the present embodiment is described.
Will be explained. Messe sent out by one transmission basically
Page consists of an address, data area, and check bits.
However, the details are the communication from master to slave and
Slightly different from communication from slave to master (Fig. 11
reference). From master to slave as shown in Figure 11
The message of destination address, data area and inspection
It is composed of Destination address send message
This is the previous logical address. Also, broadcast communication
Can specify all slaves. Day
The data area has a command at the beginning and data following it. Inspection
The check bit indicates that a bit error has occurred on the power supply signal line 42.
Redundant error detection to detect malfunction and prevent malfunction.
It is. The message from the slave to the master is
It consists of a source address, data and check bits.
Data includes acceleration digital data and self-diagnosis results.
Depends on star request. The real configuration configured as above
The operation of the embodiment is performed in the initial mode, the normal mode, and the ignition mode.
Will be explained separately. (1) Initial mode FIG. 12, FIG. 13, FIG. 16, FIG. 19, FIG.
Based on the ECU 10, the G sensor modules 20 to 2
0c and initial operation of each squib module 30 to 30g
Will be described. First, Master
The communication control circuit 15 of the ECU 10 as shown in FIG.
In step 100, n = 1 is initialized, and
Message n1 (see FIG. 23)
And power supply signal line 42 through driver receiver 11
To send to. The message n1 is as shown in FIG.
To the logical address, physical address, and data conversion circuit.
It consists of added check bits. Be each slave
The communication control circuit 23 of each G sensor module
The computer performs step 200 in FIG.
Is determined to be YES based on the message n1.
Receiving the message in step 201,
The physical address included in the message and your physical address
Match with If they match, the communication control circuit 23
In step 202, the cross computer
The logical address of the page to the memory area, and
At 203, it is confirmed that the logical address setting has been normally performed.
A message n1 '(FIG. 23, FIG.
24) and a data conversion circuit 24 and a driver receiver.
25 to the power signal line 42. Do not match
If so, ignore it. My communication control circuit 15
The cross computer determines, based on the transmission message n1 ′,
Message in step 102
Page n1 'has been received and the address
After confirming that the slave is
Step (squib module), go to step 103
To make a determination of YES, and
The message n2 (see FIGS. 23 and 24) is transferred to step 104.
In the same manner as described above. In addition,
The message n1 and the message n2 are respectively
These are for setting a logical address and for setting a development attribute. Sleigh
The communication control circuit 36 of each squib module as a
As in the processing of steps 200 to 203,
After the processing of Steps 300 to 305, go to Step 306.
Then, the expansion attribute included in the message n2 is stored in the memory.
And store the message n2 '(= message n1')
At step 307, the power supply signal line 42 is
Send. Message n2 is also received by other slaves
But the expansion attribute does not match any physical address
Is ignored. Next, the communication control circuit 15 of the ECU 10
Of the microcomputer in step 105 of FIG.
Then, upon receipt of the message message n2 ', YE
S, and at step 107, n = n + 1 = 2.
New, then, to the remaining slaves until n> N + M
Accordingly, the above initial procedure processing is repeated. All slaves
And a determination of YES is made in step 108.
Then, in step 109, the slave whose status information is 1
It is determined whether there is. This determination is NO in step 105
Is set to 1 in step 106.
It is based on what is being done. YE in step 109
If the determination is S, the airbag is
Warning that the system configuration of the
You. Thus, the initial mode ends. (2) Normal mode Next, refer to FIG. 14, FIG. 15, FIG. 17, FIG.
The ECU 10, each G sensor module 20 to 2
0c and normal operation of each squib module 30 to 30g
Will be described. FIG. 25 shows the normal mode.
Communication control circuit 15 of the ECU 10 in the
The transmission timing of the communication control circuit 23 of the sensor module.
Show. The communication control circuit 15 of the master
In step 111 of FIG.
After setting 1 and the flag f = 0, go to step 112
Reset the timer to start its timing,
At step 113, the acceleration data is
Data request command to the power signal line 42. What
Here, f = 0 indicates that the self-diagnosis signal is not transmitted.
The communication control circuit 15 uses the microcomputer.
In step 114, the power
Speed data is received, and at step 115
The end of the speed data reception is determined. This step 1
If the determination at 15 is NO, step 11
The determination in step 115 is YES in step 115
Is repeated until. Then, communication from the collision determination circuit 16 is performed.
Step 11 determines whether an ignition instruction has been issued to the control circuit 15.
6 is determined. Step 116 because there is no ignition instruction
If the determination in step (1) is NO, step 117 (FIG.
Is determined to be YES based on f = 0, and
In step 118, the self-diagnosis command is sent to the slave corresponding to n.
Is transmitted through the power signal line 42, and
At 19, f = 1 is set. Timing of the above timer
When the time has passed T0 seconds, the determination in step 120 is YE
S, and the processing after step 112 is similarly repeated.
It is. Thereafter, in step 117, based on f = 1,
If NO is determined, the
Receiving the self-diagnosis result of the slave corresponding to n
You. If there is an abnormality in the self-diagnosis result, step 122
Is YES, and at step 123,
Notification display (for example, lighting of a warning lamp). In addition, this
Warning lamps are
It is provided in the area where it can reach. On the other hand, in step 122
If the determination is no, at step 124, f = 0
Is set in step 125, and if n = M + N
It is determined whether or not. If not n = M + N, step 1
The determination at 25 is NO, and n = n + 1 at step 126.
Is updated. This processing is performed in step 125 with YE
This is repeated until the determination of S is made. Note that the
If a determination of YES is made in step 125, the step
At 127, n = 1 is set. Also the ignition finger
Is determined, the determination in step 116 is YES.
The ignition command is broadcast at step 128.
Transmitted to the power signal line 42 by the
At step 29, the flag f = 0 is set. G sensor module
The communication control circuit 23 of the
In step 204 of FIG.
D, last flag d1 and acceleration data sending flag e
In step 205, the power supply signal is set.
Receives signal on line 42 (signal other than ignition command)
I do. Next, since d = 0, step 206
Is NO, the received signal in step 205
, The logical address of the message = n or the broadcast key
If there is a signal of the multicast communication, in step 207, Y
ES is determined. Note that d1 = 1 means that the slave is its own
Is the last, and e = 1 indicates that the own slave is
Indicates that acceleration data has been sent. Then figure
In step 208 of FIG.
If there is no acceleration data request command in the
Is determined, and in step 209, the
If there is a self-diagnosis command in the signal, it is determined as YES.
You. Then, in step 210, self-diagnosis starts.
In step 211, d = 1 is set, and
In step 212, NO is determined based on e = 0.
On the other hand, if e = 1 at this stage, the process proceeds to step 212.
Is YES, and in step 213, d
1 = 1 is set. On the other hand, step 208
And the acceleration signal is requested for the received signal in step 205.
If there is a command, it is determined as YES, and step 214 is executed.
In, the acceleration data is sampled. Naturally
After the current G sensor module is
Submodule 20), since n = 1,
The determination in step 215 is YES. On the other hand,
If the determination in step 215 is NO, the step
In step 216, the signal on the power signal line 42 is transmitted.
The communication control circuit 23 controls the microcomputer.
Received. At this stage the logical address of the message =
If not n-1, the determination in step 217 is NO.
And the processing passing through steps 215, 216, and 217
Is repeated until the logical address of the message becomes n-1.
returned. Here, the determination of YES in step 217
Means n corresponding to the current G sensor module
Means After the processing of step 217, step 214
The acceleration data sampled by the
The signal is transmitted to the signal line 42. Then, step 219
Then, at step 220, d = 1 and
Then, it is determined whether or not d1 = 1. Where d = 1 and d
If 1 = 1, the determination in step 220 is YES
In step 221, the self in step 210
The diagnosis result is transmitted to the microcomputer by the communication control circuit 23.
The data is transmitted to the power signal line 42 by the computer. That
Thereafter, in step 222, d = 0 is set.
If the determination in step 220 is NO,
Steps 221 and 222 are skipped. Above
Is determined NO in step 206 as in
If the determination in step 207 is NO, step
In 223, which of logical addresses 1 to n is logical
As the address a, the microcomputer of the communication control circuit 23
Is stored in the memory of the data, and in step 224, e =
Set to 0. Also, as described above, step 205
Is performed, the determination in step 206 becomes YES.
If not, step 225 discusses the message.
It is determined whether the physical address = a. Where the logical ad
If it is less a, the determination in step 225 is YES
In step 226, the communication control circuit 23
The self-diagnosis result by the microcomputer.
The signal is transmitted to the source signal line 42. Then, step 227
Is set to d = 0. Figure 2 shows the normal mode
In summary, the ECU that is the master
10 is broadcast by the communication control circuit 15.
When an acceleration request command is sent by
The module receives the transmission command and receives the acceleration data sample.
Acceleration with sampling and logical address sampling
Transmit as degree data (digital data). Master
After receiving all acceleration data,
Send a self-diagnosis command to a specific slave with no response
I do. The specified slave performs self-diagnosis and
It enters the state of waiting for the transmission of the diagnosis result. Master in parallel with this
Is again requesting acceleration data by broadcast communication.
Send a command. G sensor module is also the same
Transmit acceleration data sampled in logical address order
I do. The slave requested for self-diagnosis is the last G sensor
Send the self-diagnosis result after the module sends. Ma
Star requests acceleration data by broadcast communication
Command and send the acceleration data request command again.
One cycle (see FIG. 25) until the communication
Or the time interval between each slave transmission and the next transmission
Is called a frame. One cycle is a G sensor
Since there are N modules, it is composed of N + 2 frames.
Is done. Set acceleration data request command to frame 0
Then, the self-diagnosis request and the transmission of the result are performed in frame N + 1.
Will do. Time interval of one cycle is fixed to T0 seconds
I do. T0 is determined by the required frequency bandwidth of acceleration.
You. (3) Ignition mode Next, from the collision detection of the passenger car to the ignition of the squib
21, 22, and 26 as an operation in the ignition mode
This will be described with reference to FIG. Communication control circuit of squib module
Reference numeral 36 denotes the microcomputer shown in FIG.
In step 308, the self-diagnosis flag is set to d = 0.
You. Next, in step 309, the power signal line
The signal on 42 is transmitted to the microcomputer by the communication control circuit 36.
Received by the computer. At this stage, d = 0
Therefore, the determination of NO is not made in step 310.
In step 311, the power supply signal line 42
Check if the logical address of the message in the signal is m or not.
Signal on signal line 42
If it is included, it is determined as YES. After that, step 312
, The signal voltage in the signal on the power supply signal line 42 is
It is determined whether or not it is at the ignition level. Here,
If the signal voltage is not at the ignition level,
The self-diagnosis command is included in the signal on the power supply signal line 42.
It is determined whether or not there is. Then, to step 313
If the determination is YES in step 314,
The microcomputer of the communication control circuit 36 performs a self-diagnosis.
Start disconnection. Then, at step 315, d = 1
Is set. NO at step 310 as described above
If the determination in step 311 is NO after the determination of
At step 316, any one of the logical addresses 1 to n
Is the micro address of the communication control circuit 36 as the logical address a.
Stored in computer memory. Also, as described above
After performing the processing of step 309 in
If the determination is YES, the process proceeds to step 317.
It is determined whether the logical address of the message = a
You. Here, when the determination in step 317 is YES
In step 318, a signal is
Is determined, and if not, in step 318
Is NO, and in step 319, the communication
The control circuit 36 performs self-diagnosis by the microcomputer.
The result is transmitted to the power signal line 42. Note that step
After the process of 319, in step 320, d = 0 is set.
Is Also, as described above, YES in step 311
Is determined, the determination in step 312 is
If YES, in step 321 the power supply
Whether there is an ignition command in the signal on the signal line 42
Is determined. Here, the presence of the ignition command
If the determination in step 321 is YES, step 322
In the example shown in FIG.
The type of collision during the message is determined by the microcontroller of the communication control circuit 36.
It is matched against the deployment attributes in the computer's memory. on the other hand,
If the determination in step 321 is NO, step
To the processing of step 309 without performing the processing of step 322.
Return. As a result of the comparison in step 322, the collision type
It is checked whether the airbag is in the collision mode to deploy.
323. And in step 324
The ignition switch 38 is controlled by the communication control circuit 36 to
It is turned on by the micro computer. Meanwhile, the communication system
The acceleration level determination circuit 37 of the control circuit 36
To the driver receiver 33 and the data conversion circuit 3
When acceleration data is input through 5, the acceleration level
The determination circuit 37 determines that the level of the acceleration data is
It is determined whether the acceleration level is equal to the acceleration level indicating the collision.
If this determination is a match, the ignition switch
The switch 39 is turned on by the acceleration level determination circuit 37.
As described above, both ignition switches 38 and 39 are turned on.
And the squib 39a is ignited and the corresponding airbag mechanism is
Deploy the airbag. The ignition mode is based on FIG.
In summary, the master collision determination circuit 16
Acceleration data sent from each G sensor module
Analysis to determine the presence or absence of a collision with the passenger car.
In the case of
Output to the communication control circuit 15 at the timing. Communication control times
Road 15 is controlled by the microcomputer
Even if data representing the morphology is received, basic cycles and
Receiving acceleration data without changing the frame
The ignition command is transmitted at frame N + 1.
Do. Here, the message containing the ignition command is a collision type
This message is received because it also contains
The communication control circuit 36 of the squib module
The computer controls the signal voltage to the ignition level (voltage range).
Box C) to determine whether the command is an ignition command
If the command is an ignition command, the collision type and the
Compare with the expansion attribute in the memory of the micro computer,
When the collision type is to be deployed, the ignition switch 38 is turned off.
On. In addition, the acceleration level judgment of the squib module
The path 37 drives acceleration data on the power signal line 42.
Read through the receiver receiver 33 and the data conversion circuit 35
The level of this acceleration data indicates that the collision of the car
If it exceeds the predetermined level indicating
Turn on. In this way, both ignition switches 38, 39
When both are turned on, the squib 39a is ignited. This
In this embodiment, in the airbag system,
Even if such a single failure occurs, the airbag system
In any of the squibs, misfires are reliably prevented and
This can prevent malfunction of the bag mechanism. Also,
Each collision type corresponding to each squib module as described above
Airbag deployment state of airbag mechanism based on 1 to P
Is controlled, so that each squib module for the car is controlled.
Of the bag mechanism according to the acceleration generated at the
The deployment state of the airbag can be secured. Note that the actual
The airbag system described in the embodiment is a mechanical
Required minimum configuration when not using
However, with such a configuration,
The effect of the state can be achieved. In addition, the present invention
For implementation, this is not limited to airbag systems.
An occupant protection system such as a belt tensioner for a seat of the passenger car.
The present invention may be applied to a stem. In addition, implementation of the present invention
In the case of collision of 30 to 30 g of each squib module,
The setting circuit 36 may be omitted. Also, in implementing the present invention,
Alternatively, the collision determination circuit 16 of the ECU 10 may be abolished.
No. In implementing the present invention, the G sensor module
The number of tools and squib modules are described in the above embodiment.
The number does not need to be limited, and may be changed as appropriate.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing an embodiment in which an airbag system according to the present invention is provided in a passenger car.

FIG. 2 is a block diagram of the airbag system.

FIG. 3 is a detailed block diagram showing a configuration of an ECU 10 of FIG.

FIG. 4 is a waveform diagram of each of voltage ranges A to C.

FIG. 5 is a diagram showing a physical address, a logical address, a development attribute, and status information corresponding to each slave stored in a memory of a microcomputer of a communication control circuit of the ECU 10 in advance.

FIG. 6 is a detailed block diagram showing a configuration of each G sensor module.

FIG. 7 is a diagram illustrating physical addresses and logical addresses stored in a memory of a microcomputer of a communication control circuit of each G sensor module.

FIG. 8 is a detailed block diagram showing a configuration of each squib module.

FIG. 9 is a diagram showing a physical address, a logical address, and a development attribute stored in a memory of a microcomputer of a communication control circuit of each squib module.

FIG. 10 is a diagram showing a format of the development attribute by a relationship between each squib module and each of collision modes 1 to P.

FIG. 11 is a diagram showing a configuration of a message from a master to a slave and a message from a slave to a master.

FIG. 12 is a part of a flowchart showing the operation of the microcomputer of the communication control circuit of the ECU 10.

FIG. 13 is a part of a flowchart showing the operation of the microcomputer of the communication control circuit of the ECU 10.

FIG. 14 is a part of a flowchart showing the operation of the microcomputer of the communication control circuit of the ECU 10.

FIG. 15 is a part of a flowchart showing the operation of the microcomputer of the communication control circuit of the ECU 10.

FIG. 16 is a part of a flowchart showing the operation of the microcomputer of the communication control circuit of each G sensor module.

FIG. 17 is a part of a flowchart showing the operation of the microcomputer of the communication control circuit of each G sensor module.

FIG. 18 is a part of a flowchart showing the operation of the microcomputer of the communication control circuit of each G sensor module.

FIG. 19 is a part of a flowchart showing the operation of the microcomputer of the communication control circuit of each squib module.

FIG. 20 is a part of a flowchart showing the operation of the microcomputer of the communication control circuit of each squib module.

FIG. 21 is a part of a flowchart showing the operation of the microcomputer of the communication control circuit of each squib module.

FIG. 22 is a part of a flowchart showing the operation of the microcomputer of the communication control circuit of each squib module.

FIG. 23 is a timing chart showing the exchange of messages between the master and the slave in the slave corresponding to the logical address n.

FIG. 24 is a diagram showing the structure of messages n1, n2, n1 ′, and n2 ′.

FIG. 25 is a timing chart showing exchange of data for each frame between the ECU 10 and each G sensor module in the normal mode.

FIG. 26 is a timing chart showing exchange of data for each frame between the ECU 10 and each G sensor module in the ignition mode.

[Explanation of symbols]

10: ECU, 15, 23, 36: communication control circuit, 16
... Collision determination circuit, 20 to 20c G sensor module, 21 acceleration sensor, 30 to 30g Squib module, 37 acceleration level determination circuit, 38, 39 ignition switch, 39a squib, 40 serial communication bus.

Continued on the front page (72) Inventor Fumio Asakura 14 Iwatani, Shimowasumi-cho, Nishio-shi, Aichi Prefecture Inside Japan Automotive Parts Research Institute (72) Inventor Akira Kondo 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture DENSO Corporation F-term (reference) 3D054 EE42 FF16

Claims (7)

[Claims] A plurality of occupant protection mechanisms, a plurality of acceleration sensor modules (20 to 20c), a plurality of squib modules (30 to 30g), and an electronic control unit (10) mounted at different positions of the vehicle. And a serial communication bus (40) connecting the acceleration sensor modules, the squib modules, and the electronic control unit, wherein the plurality of acceleration sensor modules are: An acceleration sensor (21) for detecting the acceleration of the vehicle at different positions of the vehicle, and transmission means (23, 218) for transmitting the detected acceleration of the acceleration sensor to the serial communication bus as corresponding squib module acceleration data. Wherein the electronic control unit includes a module for the corresponding squib module on the serial communication bus. Collision determination means (15, 16, 116) for determining the presence or absence of a vehicle collision based on the degree data, and transmitting the determination result as the corresponding squib module determination data to the serial communication bus. Each of the modules is a squib (39a) that is driven when a corresponding occupant protection mechanism of the plurality of occupant protection mechanisms is operated, and is connected in series with the squib and drives the squib only when both are turned on. Two ignition switches (38, 39); collision determination means (37) for determining the presence or absence of a vehicle collision based on the acceleration data for the corresponding squib module on the serial communication bus and turning on one of the two ignition switches; The other ignition switch of the two ignition switches, the corresponding squib module determination data on the serial communication bus A vehicle occupant protection system which is turned on when the vehicle indicates a vehicle collision. 2. The electronic control unit further comprises: ignition command transmission means (128) for transmitting a corresponding squib module ignition command to any one of the plurality of squib modules to the serial communication bus. Receiving the ignition command for the corresponding squib module on the serial communication bus, and determining the presence or absence of a vehicle collision based on the determination data for the corresponding squib module on the serial communication bus. 2. The vehicle occupant protection system according to claim 1, further comprising another collision determination unit (321 to 324) that turns on the other ignition switch when the presence of the vehicle is determined. 3. The electronic control unit according to claim 2, wherein the collision determination means transmits the corresponding squib module determination data to the serial communication bus in a signal form different from the corresponding squib module acceleration data. Claim 1
Or the vehicle occupant protection system according to 2. 4. The signal form of the corresponding squib module determination data has a voltage amplitude different from that of the corresponding squib module acceleration data.
3. The vehicle occupant protection system according to claim 1. 5. The vehicle occupant protection system according to claim 1, wherein the collision determination means of the electronic control unit determines the vehicle including a collision type of the vehicle. 6. The vehicle according to claim 2, wherein one of the two collision determination units of the plurality of squib modules determines the collision type including a collision type of the vehicle. Occupant protection system. 7. The serial communication device according to claim 6, wherein immediately after the electronic control device starts operating, the serial communication transmits information to be used by one of the two collision determination units of the plurality of squib modules to determine a collision condition of the vehicle. Information transmitting means (1
04), wherein one of the collision determining means of each of the plurality of squib modules makes a determination including a collision type of the vehicle based on the information on the serial communication bus. 5. The vehicle occupant protection system according to any one of claims 4 to 4.