JP4457311B2 - Vehicle occupant protection device - Google Patents

Description

  The present invention relates to a vehicle occupant protection device for protecting a vehicle occupant.

  An example of a vehicle occupant protection device that protects a vehicle occupant is an airbag device. When the vehicle collides, the airbag is deployed by the activation device to protect the occupant. Conventionally, as an activation device for an airbag device, for example, there is an activation control device for an occupant protection device disclosed in Japanese Patent Application Laid-Open No. 2003-54359. The activation control device includes a front sensor, a floor sensor, and an electronic control unit. The front sensor is disposed on the right front part and the left front side member of the vehicle. The floor sensor is disposed near the floor tunnel in the center of the vehicle. The front sensor and the floor sensor are sensors that detect deceleration in the vehicle front-rear direction at each location. The electronic control unit is a device that activates the airbag based on the deceleration detected by the front sensor and the floor sensor. In the electronic control unit, a determination map for determining whether to activate the airbag based on the deceleration is recorded. The determination map includes a high map, a low map, and a front map.

  When the floor deceleration detected by the floor sensor exceeds a threshold on the High map, the electronic control unit activates the airbag. Further, when the floor deceleration detected by the floor sensor exceeds the threshold on the Low map and the front deceleration detected by the front sensor exceeds the threshold on the front map, the airbag is activated. As a result, the airbag is deployed to protect the occupant.

By the way, since the front sensor is disposed in the front part of the vehicle, there is a possibility that the front sensor may be destroyed at the time of a vehicle collision. Moreover, the wire harness which connects a front sensor to an electronic control unit may also be disconnected. Therefore, even when the vehicle collides, the arrangement is devised so that the front sensor is not destroyed or the wire harness is not disconnected. However, it is impossible to completely prevent the front sensor from being broken or the wire harness from being disconnected in the event of a vehicle collision. Therefore, when the signal from the front sensor is interrupted, it is determined that the front sensor is broken or the wire harness is disconnected due to a vehicle collision, and the determination based on the front map is forcibly turned on. Thus, even if the front sensor is broken or the wire harness is disconnected in the event of a vehicle collision, the airbag can be activated based on the determination based on the low map and the front map.
JP 2003-54359 A

  However, the interruption of the signal from the front sensor does not occur only when the vehicle collides. It is also caused by a failure of the front sensor or a failure of the input circuit of the electronic control unit. For example, if the vehicle is flooded and exposed to an excessively wet condition exceeding the operation guarantee range, the front sensor and the input circuit of the electronic control unit may break down. Furthermore, there is a possibility that the floor deceleration detected by the floor sensor gradually changes due to leakage of moisture.

  If the input circuit of the front sensor or the electronic control unit breaks down and the signal is interrupted, the determination by the front map is forcibly turned on. At this time, if the floor deceleration detected by the floor sensor gradually changes and exceeds the threshold on the Low map, the airbag is activated even though the vehicle has not collided.

  This invention is made | formed in view of such a situation, and it starts based on the output signal of a 1st sensor, a 2nd sensor, and a 3rd sensor, and is at least any one of a 2nd sensor or a 3rd sensor. In a vehicle occupant protection device that can be activated even when the output signal of the vehicle is interrupted, a highly reliable vehicle occupant protection device that does not malfunction even if it is exposed to an excessively wet state exceeding the operation guarantee range is provided. For the purpose.

  Therefore, as a result of intensive research and trial and error to solve this problem, the present inventor does not activate the vehicle occupant protection device when both the output signals of the second sensor and the third sensor are interrupted. Thus, the present invention has been completed with the idea that malfunctions can be prevented even when exposed to excessive moisture.

  That is, the vehicle occupant protection device according to claim 1 is a protection device that protects a vehicle occupant, a first sensor that outputs a signal corresponding to the magnitude of an impact applied to the vehicle, and the first sensor When the magnitude of the impact based on the output signal is greater than or equal to a first predetermined threshold, the first control signal generating means for outputting the first control signal and the first sensor are disposed in front of the vehicle, and the impact applied to the vehicle A second sensor for outputting a signal corresponding to the magnitude, and a second control signal generating means for outputting a second control signal when the magnitude of the impact based on the output signal of the second sensor is equal to or greater than a second predetermined threshold; A third sensor disposed in front of the vehicle from the first sensor and outputting a signal corresponding to the magnitude of the impact applied to the vehicle; and a magnitude of the impact based on the output signal of the third sensor is a third predetermined value. When the threshold is exceeded, the third control signal is output. The third control signal generating means, the interruption of the output signal of the second sensor input to the second control signal generating means, or the output signal of the third sensor input to the third control signal generating means. When at least one of the interruptions is detected, fourth control signal generating means for outputting a fourth control signal, the first control signal is output, and the second control signal, the third control signal, or the second When any one of the four control signals is output, the vehicle occupant protection device includes an activation signal generation unit that outputs an activation signal for activating the protection device. The fourth control signal generation unit includes: When the interruption of the output signal of the second sensor and the interruption of the output signal of the third sensor are both detected, the output of the fourth control signal is stopped.

  The vehicle occupant protection device according to claim 2 is the vehicle occupant protection device according to claim 1, wherein the fourth control signal generating means further includes the interruption of the output signal of the second sensor and the third control signal. The output of the fourth control signal is stopped for a predetermined time when both interruptions of the output signal of the sensor are detected.

  The vehicle occupant protection device according to claim 3 is the vehicle occupant protection device according to claim 1 or 2, further comprising: a first control signal generating means for transmitting an output signal of the second sensor to the second control signal generating means. A communication circuit; and a second communication circuit for transmitting an output signal of the third sensor to the third control signal generating means. The first communication circuit and the second communication circuit are in the same IC package. It is configured.

  The vehicle occupant protection device according to claim 4 is the vehicle occupant protection device according to claim 1 or 2, further comprising a third communication circuit for transmitting an output signal of the second sensor, and the third sensor. The fourth communication circuit for transmitting the output signal of the second communication signal and the output signal of the third communication circuit to the second control signal generating means, or the output signal of the fourth communication circuit to the third control signal generating means. Each of the third communication circuit, the fourth communication circuit, and the fifth communication circuit is configured in the same IC package.

  The first to third sensors, the first to third predetermined threshold values, the first to fourth control signals, the first to fourth control signal generating means, and the first to fifth communications referred to in this specification. The circuit is introduced for convenience in order to distinguish the sensor, the predetermined threshold value, the control signal, the control signal generation means, and the communication circuit.

  According to the vehicle occupant protection device of the first aspect, malfunction can be prevented even if the vehicle is exposed to an excessively wet state exceeding the operation guarantee range. Thereby, the reliability of the vehicle occupant protection device can be improved. If the vehicle occupant protection device is exposed to an excessively wet state, not only the output signal of the second sensor but also the output signal of the third sensor is interrupted due to electric leakage. For this reason, when both the output signal of the second sensor and the output signal of the third sensor are detected, these interruptions are not caused by a vehicle collision but are caused by being exposed to an excessively wet condition. It can be determined that there is. At this time, since the output signals of the second sensor and the third sensor are interrupted, the second control signal and the third control signal are not output. Also, the fourth control signal is not output. Therefore, the output of the start signal can be stopped by stopping the output of the second control signal, the third control signal, and the fourth control signal, and the vehicle occupant protection device due to being exposed to an excessively wet state. Can be prevented from malfunctioning.

  According to the vehicle occupant protection device of the second aspect, it is possible to reliably prevent malfunction. If the vehicle occupant protection device is exposed to an excessively wet state, not only the output signal of the second sensor but also the output signal of the third sensor is interrupted due to electric leakage. However, there may be a case where an unstable operation is performed so that the interruption is temporarily eliminated even though the vehicle is flooded. For this reason, when both the output signal of the second sensor and the output signal of the third sensor are detected, the output of the fourth control signal is stopped for a predetermined time regardless of the state of the subsequent output signal. Can be reliably prevented.

  According to the vehicle occupant protection device of the third aspect, the malfunction can be prevented and the device can be miniaturized. By configuring the first communication circuit and the second communication circuit in the same IC package, the apparatus can be reduced in size. Furthermore, when exposed to an excessive water exposure condition, the first communication circuit and the second communication circuit both fail due to electric leakage because they are configured in the same IC package, and not only the output signal of the second sensor. The output signal of the third sensor is also interrupted. Therefore, it can be determined with certainty that it has been exposed to an excessively wet state. As a result, malfunction can be prevented and the apparatus can be miniaturized.

  According to the vehicle occupant protection device of the fourth aspect, it is possible to prevent malfunction and simplify the transmission path of the output signals of the second sensor and the third sensor. By transmitting the output signals of the second sensor and the third sensor to the second control signal generating unit and the third control signal generating unit via the fifth communication circuit, the signal transmission path can be simplified. Furthermore, when exposed to an excessive water exposure condition, the third IC circuit and the fourth communication circuit fail due to electric leakage because they are configured in the same IC package, and not only the output signal of the second sensor. The output signal of the third sensor is also interrupted. Even if the fifth communication circuit fails, the output signals of the second sensor and the third sensor are similarly interrupted. Therefore, it can be determined with certainty that it has been exposed to an excessively wet state. Thereby, while preventing malfunctioning, the transmission path of the output signal of a 2nd sensor and a 3rd sensor can be simplified.

  This embodiment shows an example in which the vehicle occupant protection device according to the present invention is applied to an airbag device that deploys an airbag to protect the occupant.

(First embodiment)
FIG. 1 is a block diagram of the airbag device in the first embodiment, FIG. 2 is a hardware configuration diagram of the airbag device, and FIGS. 3 to 7 are flowcharts relating to the operation of the airbag device. And it demonstrates concretely in order of a structure, operation | movement, and an effect with reference to FIGS.

  First, a specific configuration will be described with reference to FIGS. As shown in FIG. 1, the airbag device 1 (vehicle occupant protection device) is a device that determines a vehicle collision based on the acceleration of each part of the vehicle and activates the airbag to protect the vehicle occupant. The airbag device 1 includes a floor sensor 10 (first sensor), a main determination unit 11, a first front sensor 12 (second sensor), a second front sensor 13 (third sensor), and a safing determination unit. 14, an activation signal generation unit 15, and a protection device 16.

  The floor sensor 10 is a sensor that is arranged at a substantially central portion of the vehicle and detects acceleration in the vehicle front-rear direction that occurs when the vehicle collides. The floor sensor 10 outputs an analog signal corresponding to the magnitude of acceleration to the main determination unit 11.

  The main determination unit 11 is a block that determines the presence or absence of a vehicle collision based on the acceleration detected by the floor sensor 10 and outputs a signal corresponding to the determination result. The main determination unit 11 includes an A / D converter 110, a high-pass filter 111 (hereinafter referred to as HPF), a low-pass filter 112 (hereinafter referred to as LPF), a high-speed collision determination unit 113, a low-speed collision determination unit 114, And a collision-on signal generation unit 115. Here, as shown in FIG. 2, the A / D converter 110 is provided in the microcomputer 20. Further, the HPF 111, the LPF 112, the high-speed collision determination unit 113, the low-speed collision determination unit 114, and the collision on signal generation unit 115 are configured by the microcomputer 20 and a program. The high-speed collision determination unit 113 and the collision-on signal generation unit 115, and the low-speed collision determination unit 114 and the collision-on signal generation unit 115 respectively correspond to the first control signal generation unit in the present invention.

  Returning to FIG. As shown in FIG. 1, the A / D converter 110 is an element that converts an analog signal output from the floor sensor 10 into a digital signal. The A / D converter 110 converts the analog signal output from the floor sensor 10 into a digital signal and outputs the digital signal to the HPF 111 as acceleration data.

  The HPF 111 performs filtering processing on acceleration data output from the A / D converter 110. The HPF 111 performs zero point correction processing on the acceleration data to eliminate drift errors in the acceleration data, and outputs the acceleration data to the LPF 112.

  The LPF 112 performs filtering processing on acceleration data output from the HPF 111. The LPF 112 removes a high-frequency component of acceleration data and outputs it to the high-speed collision determination unit 113 and the low-speed collision determination unit 114 in order to extract a frequency component of, for example, 100 Hz or less used for collision determination.

The high-speed collision determination unit 113 is a block that determines whether or not the vehicle collision is a high-speed collision based on the acceleration data output from the LPF 112. The high-speed collision determination unit 113 integrates the acceleration data output from the LPF 112 with an integration width of 8 ms, for example. Further, the interval integral value of the acceleration data is compared with a preset high-speed collision threshold (first predetermined threshold), for example, a value corresponding to the interval integral value of acceleration 196 m / s ² . When the interval integral value of the acceleration data is equal to or higher than the high speed collision threshold, the high speed collision determination unit 113 determines that the vehicle collision is a high speed collision and outputs a high speed collision on signal to the collision on signal generation unit 115.

The low-speed collision determination unit 114 is a block that determines whether or not the vehicle collision is a low-speed collision based on the acceleration data output from the LPF 112. The low-speed collision determination unit 114 integrates the acceleration data output from the LPF 112 for an interval with an integration width of, for example, 32 ms. Further, the interval integral value of the acceleration data is compared with a preset low-speed collision threshold (first predetermined threshold), for example, a value corresponding to the interval integral value of acceleration 49 m / s ² . When the interval integral value of the acceleration data is equal to or higher than the low-speed collision threshold, the low-speed collision determination unit 114 determines that the vehicle collision is a low-speed collision and outputs a low-speed collision on signal to the collision signal generation unit 115.

  The collision on signal generation unit 115 determines whether the vehicle has collided at high speed or low speed based on the output signals of the high speed collision determination unit 113 and the low speed collision determination unit 114, and the collision on signal (first control signal). Is output to the activation signal generator 15. When the high-speed collision on signal or the low-speed collision on signal is output, the collision on signal generation unit 115 outputs the collision on signal to the activation signal generation unit 15 for a predetermined time.

  The safing determination unit 14 is a block that determines the presence or absence of a vehicle collision based on the acceleration detected by the first front sensor 12 and the second front sensor 13 and outputs a signal corresponding to the determination result. The safing determination unit 14 includes serial communication interfaces 140 and 141 (hereinafter referred to as serial communication I / F), high-pass filters 142 and 143 (hereinafter referred to as HPF), a first safing determination unit 144, and a second safe. A judging unit 145, a safing on signal generator 146, a communication disruption judging unit 147, 148, and a safing forced on signal generator 149. Here, as shown in FIG. 2, the serial communication I / F 140 includes a communication circuit 21, and the serial communication I / F 141 includes a communication circuit 22. The communication circuits 21 and 22 are packaged as an IC 23 in one package. Further, HPFs 142 and 143, first safing determination unit 144, second safing determination unit 145, safing on signal generation unit 146, communication disruption determination units 147 and 148, and safing forced on signal generation unit Reference numeral 149 includes a microcomputer 20 and a program. Note that the first safing determination unit 144 and the second safing determination unit 145 correspond to the second control signal generation unit and the third control signal generation unit in the present invention, respectively. Further, the communication interruption determination units 147 and 148 and the safing forced-on determination unit 149 correspond to the fourth control signal generation unit in the present invention. Further, the safing-on signal generation unit 146 and the activation signal generation unit 15 correspond to the activation signal generation unit in the present invention.

  Returning to FIG. As shown in FIG. 1, the 1st front sensor 12 and the 2nd front sensor 13 are sensors which are arrange | positioned at the vehicle right front part and the left front part, and detect the acceleration of the vehicle front-back direction which generate | occur | produces at the time of a vehicle collision. The first front sensor 12 and the second front sensor 13 serially transmit digital signals corresponding to the magnitude of acceleration to the serial communication I / Fs 140 and 141.

  The serial communication I / Fs 140 and 141 are circuits that convert digital signals transmitted serially from the first front sensor 12 and the second front sensor 13 into acceleration data. The serial communication I / Fs 140 and 141 receive digital signals transmitted serially from the first front sensor 12 and the second front sensor 13 and output them to the HPFs 142 and 143 as acceleration data.

  The HPFs 142 and 143 filter the acceleration data output from the serial communication I / Fs 140 and 141. The HPFs 142 and 143 perform zero point correction processing on the acceleration data in order to eliminate the drift error of the acceleration data, and output it to the first safing determination unit 144 and the second safing determination unit 145.

The first safing determination unit 144 and the second safing determination unit 145 are blocks that determine the presence or absence of a vehicle collision based on the acceleration data output from the HPFs 142 and 143. The first safing determination unit 144 and the second safing determination unit 145 integrate the acceleration data output from the HPFs 142 and 143, for example, with an integration width of 10 ms. Further, the interval integral value of the acceleration data corresponds to a preset first safing threshold (second predetermined threshold), second safing threshold (third predetermined threshold), for example, an interval integral value of acceleration 49 m / s ^2. Compare with the value you want. When the interval integral value of the acceleration data is greater than or equal to the first safing threshold and the second safing threshold, the first safing determination unit 144 and the second safing determination unit 145 determine that a vehicle collision has occurred. The first safing on signal (second control signal) and the second safing on signal (third control signal) are output to the safing on signal generator 146.

  The safing on signal generation unit 146 determines the presence or absence of a vehicle collision based on the output signals of the first safing determination unit 144 and the second safing determination unit 145, and sends the safing on signal to the activation signal generation unit 15. This is the output block. When the first safing on signal or the second safing on signal is output, the safing on signal generator 146 outputs the safing on signal to the activation signal generator 15 for a predetermined time.

  The communication interruption determination units 147 and 148 are blocks that determine whether or not digital signals serially transmitted from the first front sensor 12 and the second front sensor 13 to the serial communication I / Fs 140 and 141 are interrupted. The communication interruption determination unit 147, 148 determines that the serial communication has been interrupted when the state in which the digital signal is not normally received continues for a predetermined time (third predetermined time), for example, 5 ms or more, and the first communication interruption is turned on. The signal and the second communication interruption on signal are output to the safing forced on signal generation unit 149. Here, the state in which the digital signal cannot be normally received is a state in which there is no response even though transmission of the digital signal is requested, a state in which an unspecified digital signal is received, or a checksum or When an error detection function such as CRC is provided, this corresponds to a state where a checksum abnormality or CRC abnormality occurs.

  The safing forced on signal generation means 149 determines the presence or absence of communication disruption based on the output signals of the communication disruption determination units 147 and 148, and generates a safing forced on signal (fourth control signal) as the activation signal generation unit 15. Is a block to output to If both the first communication disruption on signal and the second communication disruption on signal are not output, the safing forced on signal generation unit 149 does not output the safing forced on signal. In contrast, when either the first communication disruption on signal or the second communication disruption on signal is output, the safing forced on signal generation unit 149 outputs the safing forced on signal for a predetermined time. However, when both the first communication disruption on signal and the second communication disruption on signal are output, the output of the safing forced on signal is stopped for a predetermined time.

  The activation signal generation unit 15 includes a collision on signal output from the collision on signal generation unit 115, a safing on signal output from the safing on signal generation unit 146, and a forced safing output from the safing forced on signal generation unit 149. This block outputs an activation signal for activating the protection device 16 based on the ON signal. The activation signal generation unit 15 outputs the activation signal to the protection device 16 when the collision on signal is output and either the safing on signal or the safing forced on signal is output. That is, when the collision on signal is output and the first safing on signal, the second safing on signal or the safing forced on signal is output, the start signal is output.

  The protection device 16 is a device that operates based on the activation signal output from the activation signal generation unit 15 and protects the vehicle occupant. Although not shown, the protection device 16 includes an airbag, a squib, and a squib drive circuit.

  Next, a specific operation of the airbag device 1 will be described. As shown in FIG. 3, the serial communication I / F 140 receives acceleration data transmitted from the first front sensor 12 (S100). The communication interruption detection unit 147 determines whether or not the acceleration data can be normally received (S101).

  In step S <b> 101, when the acceleration data can be normally received, the serial communication I / F 140 outputs the received acceleration data to the HPF 142 based on an instruction from the communication interruption detection unit 147. On the other hand, when the acceleration data is not normally received in step S101, the communication interruption detecting unit 147 determines whether or not the state where the acceleration data is not normally received continues for 5 ms or more (S102).

  In step S102, when the state where acceleration data cannot be normally received continues for 5 ms or longer, the communication interruption detection unit 147 determines that communication is interrupted, and outputs a first communication interruption ON signal ( S103). On the other hand, in step S102, when the state in which reception is not successful continues for less than 5 ms, the communication interruption detection unit 147 determines that there is a temporary abnormality in acceleration data and communication is not interrupted. . If it is determined that the communication is not interrupted, the serial communication I / F 140 outputs the last acceleration data that has been normally received to the HPF 142 (S104).

  The HPF 142 performs a filtering process on the acceleration data output from the serial communication I / F 140, and outputs the filtered data to the first safing determination unit 144 (S105). The first safing determination unit 144 performs interval integration on the filtered acceleration data (S106). Thereafter, the first safing determination unit 144 compares the interval integral value of the acceleration data of the first front sensor 12 with the first safing threshold (S107).

  In step S107, when the interval integral value of the acceleration data is greater than or equal to the first safing threshold value, the first safing determination unit 144 determines that the vehicle has collided and outputs a first safing on signal (S108). On the other hand, in step S107, when the interval integral value of the acceleration data is less than the first safing threshold, the first safing determination unit 144 determines that the vehicle has not collided. At this time, the first safing on signal is not output.

  Thereafter, the same process is performed on the acceleration data transmitted from the second front sensor 13 (S109 to S117).

  Subsequently, processing for the analog signal output from the floor sensor 10 is performed. As shown in FIG. 4, the A / D converter 110 receives an analog signal output from the floor sensor 10 (S118). Further, the input analog signal is converted into a digital signal and output as acceleration data to the HPF 111 (S119). The HPF 111 performs a filtering process on the acceleration data output from the A / D converter 噐 110 and outputs the filtered data to the LPF 112. The LPF 112 further performs a filtering process on the acceleration data output from the HPF 111 and outputs the filtered data to the high speed collision determination unit 113 and the low speed collision determination unit 114 (S120). The high-speed collision determination unit 113 performs interval integration on the filtered acceleration data (S121). Thereafter, the high-speed collision determination unit 113 compares the interval integral value of the acceleration data of the floor sensor 10 with the high-speed collision threshold (S122).

  In step S122, when the interval integral value of the acceleration data is equal to or higher than the high-speed collision threshold, the high-speed collision determination unit 113 determines that the vehicle collision is a high-speed collision, and outputs a high-speed collision on signal (S123). In contrast, in step S122, when the interval integral value of the acceleration data is less than the high speed collision threshold, the high speed collision determination unit 113 determines that the vehicle collision is not a high speed collision. At this time, the high-speed collision on signal is not output.

  The low-speed collision determination unit 114 performs interval integration on the filtered acceleration data (S124). The low speed collision determination unit 114 compares the interval integral value of the acceleration data of the floor sensor 10 with the low speed collision threshold (S125).

  In step S125, when the interval integral value of the acceleration data is equal to or higher than the low-speed collision threshold, the low-speed collision determination unit 114 determines that the vehicle collision is a low-speed collision and outputs a low-speed collision on signal (S126). On the other hand, when the interval integral value of the acceleration data is less than the low-speed collision threshold value in step S125, the low-speed collision determination unit 114 determines that the vehicle collision is not a low-speed collision. At this time, the low-speed collision on signal is not output.

  Subsequently, processing on the output signals of the first safing determination unit 144, the second safing determination unit 145, and the safing forced on signal generation unit 149 is performed. As shown in FIG. 5, the safing-on signal generation unit 146 determines whether or not the first safing-on signal is output (S127). Further, it is determined whether or not the second safing on signal is output (S128).

  In steps S127 and S128, when the first safing on signal is output or the second safing on signal is output, the safing on signal generation unit 146 outputs the safing on signal for a predetermined time. (S129). On the other hand, in steps S127 and S128, when neither the first safing on signal nor the second safing on signal is output, the safing on signal is not output. At this time, the safing forced on signal generator 149 determines whether safing forced on is prohibited (S130).

  In step S130, when safing forced on is prohibited, the safing forced on signal generator 149 does not output a safing forced on signal. On the other hand, when safing forced on is not prohibited in step S130, the safing forced on signal generation unit 149 determines whether or not the first communication disruption on signal is output (S131). Further, it is determined whether or not a second communication interruption on signal is output (S132, S133).

  In steps S131 to S133, when neither the first communication interruption on signal nor the second communication interruption on signal is output, the safing forced on signal generation unit 149 does not output the safing forced on signal. On the other hand, when either the first communication disruption on signal or the second communication disruption on signal is output in steps S131 to S133, the safing forced on signal generation unit 149 outputs a safing forced on signal to a predetermined value. The time is output (S134). However, when both the first communication interruption on signal and the second communication interruption on signal are output, the output of the safing forced on signal is stopped for a predetermined time (S135).

  Subsequently, processing on the output signals of the high-speed collision determination unit 113 and the low-speed collision determination unit 114 is performed. As shown in FIG. 6, the collision on signal generation unit 115 determines whether or not a high speed collision on signal is output (S136). Further, it is determined whether or not a low-speed collision on signal is output (S137).

  In steps S136 and S137, when either the high-speed collision on signal or the low-speed collision on signal is output, the collision on signal generation unit 115 outputs a collision on signal (S138). On the other hand, when both the high speed collision on signal and the low speed collision on signal are not output in steps S136 and S137, the collision on signal is not output.

  Subsequently, processing on the output signals of the safing on signal generation unit 146, the safing forced on signal generation unit 149, and the collision on signal generation unit 115 is performed. As illustrated in FIG. 7, the activation signal generation unit 15 determines whether or not a safing on signal is output (S139). Further, it is determined whether or not a safing forced on signal is output (S140).

  In steps S139 and S140, when either the safing on signal or the safing forced on signal is output, the activation signal generator 15 determines whether or not a collision on signal is output (S141). In step S141, when the collision-on signal is output, the activation signal generator 15 outputs the activation signal for a predetermined time (S142). On the other hand, in steps S139 and S140, when neither the safing on signal nor the safing forced on signal is output, the start signal is not output. In step S141, the start signal is not output even when the collision on signal is not output.

  Finally, specific effects will be described. According to the first embodiment, malfunction can be prevented even when exposed to an excessively wet state exceeding the operation guarantee range. Thereby, the reliability of the airbag apparatus 1 can be improved. When exposed to an excessively wet state, the airbag device 1 breaks not only the output signal of the first front sensor 12 but also the output signal of the second front sensor 13 due to electric leakage. Therefore, when both the interruption of the output signal of the first front sensor 12 and the interruption of the output signal of the second front sensor 13 are detected, these interruptions were not caused by a vehicle collision but were exposed to an excessively wet state. It can be determined that this is the case. At this time, since the output signals of the first front sensor 12 and the second front sensor 13 are interrupted, the first safing on signal and the second safing on signal are not output. Also, no safing forced on signal is output. For this reason, the output of the start signal can be stopped by stopping the output of the first safing on signal, the second safing on signal, and the safing forced on signal, which is caused by being exposed to an excessively wet state. The malfunction of the airbag apparatus 1 can be prevented.

  In addition, according to the first embodiment, when both the first communication interruption on signal and the second communication interruption on signal are output, the output of the safing forced on signal is stopped for a predetermined time, thereby reliably preventing malfunction. can do. When exposed to an excessively wet state, not only the output signal of the first front sensor 12 but also the output signal of the second front sensor 13 is interrupted due to electric leakage. However, there may be a case where an unstable operation is performed so that the interruption is temporarily eliminated even though the vehicle is flooded. Therefore, when both the first communication disruption on signal and the second communication disruption on signal are output, regardless of the state of the subsequent signals, the output of the safing forced on signal is stopped for a predetermined time, thereby ensuring a malfunction. Can be prevented.

  Furthermore, according to the first embodiment, it is possible to prevent malfunction and reduce the size of the apparatus. By configuring the serial communication I / Fs 140 and 141 as the communication circuits 21 and 22 in the same package of the IC 23, the airbag device 1 can be downsized. When exposed to an excessively wet state, the IC 23 is configured in the same package, so that both the communication circuits 21 and 22 fail due to electric leakage, and not only the output signal of the first front sensor 12 but also the second front sensor. 13 output signals are also interrupted. Therefore, it can be determined with certainty that it has been exposed to an excessively wet state. As a result, malfunction can be prevented and the apparatus can be miniaturized.

(Second Embodiment)
Next, the hardware block diagram of the airbag apparatus in 2nd Embodiment is shown in FIG. Since the block diagram and operation of the airbag apparatus in the second embodiment are exactly the same as those of the airbag apparatus in the first embodiment, a description thereof will be omitted. Here, only the configuration of the hardware, which is different from the airbag device in the first embodiment, will be described, and the description of the common portions other than the necessary portions will be omitted. In addition, the same code | symbol is attached | subjected and demonstrated to the element same as 1st Embodiment.

  As shown in FIG. 8, the serial communication I / F 140 includes communication circuits 24 and 26, and the serial communication I / F 141 includes communication circuits 25 and 26, respectively. The communication circuit 24 transmits the output signal of the first front sensor 12 to the communication circuit 26. The communication circuit 25 transmits the output signal of the second front sensor 13 to the communication circuit 26. The communication circuit 26 outputs the output signal of the communication circuit 24 to the HPF 142 configured in the microcomputer 20 or the output of the communication circuit 25 to the HPF 143 configured in the microcomputer 20 in accordance with a predetermined procedure. Each signal is selected and transmitted. The communication circuits 24-26 are packaged as an IC.

  Finally, specific effects will be described. According to the second embodiment, it is possible to prevent malfunction and simplify the transmission path of the output signals of the first front sensor 12 and the second front sensor 13. By transmitting the output signals of the first front sensor 12 and the second front sensor 13 to the microcomputer 20 via the communication circuit 26, the signal transmission path can be simplified. Furthermore, when exposed to excessive water, the IC 27 is configured in the same package. Therefore, the communication circuits 24 and 25 are broken due to electric leakage, and not only the output signal of the first front sensor 12 but also the second signal. The output signal of the front sensor 13 is also interrupted. Even if the communication circuit 26 breaks down, the output signals of the first front sensor 12 and the second front sensor 13 are similarly interrupted. Therefore, it can be determined with certainty that it has been exposed to an excessively wet state. Thereby, while preventing malfunctioning, the transmission path of the output signal of the 1st front sensor 12 and the 2nd front sensor 13 can be simplified.

  In the first and second embodiments, various threshold values are used and various signals are output when the threshold value is equal to or higher than the threshold value. However, the present invention is not limited to this. A signal may be output when the threshold value is exceeded. In the first and second embodiments, examples in which these threshold values are constant are given, but the present invention is not limited to this. You may make it change the value of a threshold value according to the change of a vehicle state, for example, vehicle speed.

The block diagram of the airbag apparatus in 1st Embodiment is shown. The block diagram of the hardware of the airbag apparatus in FIG. 1 is shown. The flowchart regarding operation | movement of the airbag apparatus in FIG. 1 is shown. The continuation of the flowchart in FIG. 3 is shown. The continuation of the flowchart in FIG. 4 is shown. The continuation of the flowchart in FIG. 5 is shown. The continuation of the flowchart in FIG. 6 is shown. The block diagram of the hardware of the airbag apparatus in 2nd Embodiment is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Airbag apparatus (occupant protection apparatus for vehicles), 10 ... Floor sensor (1st sensor), 11 ... Main determination part, 110 ... A / D converter, 111 ... HPF , 112... LPF, 113... High-speed collision determination unit, 114... Low-speed collision determination unit, 115... Collision on signal generation unit, 12. ... 2nd front sensor (3rd sensor), 14 ... Safing judgment part, 140, 141 ... Serial communication I / F, 142, 143 ... HPF, 144 ... 1st safing Determining unit, 145, second safing determining unit, 146, safing on signal generating unit, 147, 148 ... communication disruption determining unit, 149 ... safing forced on signal generating unit, ..Start signal generator 6 ... protector, 20 ... microcomputer, 21,22,24～26 ... communication circuit, 23, 27 ... IC

Claims (4)

A protection device for protecting a vehicle occupant, a first sensor that outputs a signal corresponding to the magnitude of impact applied to the vehicle, and a magnitude of impact based on the output signal of the first sensor is greater than or equal to a first predetermined threshold value A first control signal generating means for outputting a first control signal, a second sensor disposed in front of the vehicle from the first sensor and outputting a signal corresponding to the magnitude of an impact applied to the vehicle, A second control signal generating means for outputting a second control signal when the magnitude of the impact based on the output signal of the second sensor is equal to or greater than a second predetermined threshold; A third sensor that outputs a signal corresponding to the magnitude of the impact applied to the first sensor, and a third control that outputs a third control signal when the magnitude of the impact based on the output signal of the third sensor is greater than or equal to a third predetermined threshold. A signal generating means and the second control signal generator; When at least one of the interruption of the output signal of the second sensor input to the means and the interruption of the output signal of the third sensor input to the third control signal generation means is detected, the fourth control signal is A fourth control signal generating means for outputting, and when the first control signal is output and either the second control signal or the third control signal or the fourth control signal is output, the protection device In a vehicle occupant protection device comprising an activation signal generating means for outputting an activation signal for activating the vehicle,
The fourth control signal generating means stops the output of the fourth control signal when both the interruption of the output signal of the second sensor and the interruption of the output signal of the third sensor are detected. Occupant protection device.   The fourth control signal generating means stops the output of the fourth control signal for a predetermined time when both the output signal of the second sensor and the output signal of the third sensor are detected. The vehicle occupant protection device according to claim 1.   A first communication circuit that transmits an output signal of the second sensor to the second control signal generation unit; and a second communication circuit that transmits an output signal of the third sensor to the third control signal generation unit. The vehicle occupant protection apparatus according to claim 1, wherein the first communication circuit and the second communication circuit are configured in the same IC package.   A third communication circuit for transmitting an output signal of the second sensor, a fourth communication circuit for transmitting an output signal of the third sensor, and an output signal of the third communication circuit to the second control signal generating means; Or a fifth communication circuit that selectively transmits the output signal of the fourth communication circuit to the third control signal generation means, the third communication circuit, the fourth communication circuit, and the fifth The vehicle occupant protection device according to claim 1, wherein the communication circuit is configured in the same IC package.

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