JP2007030799A - Vehicular side impact detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular side impact detector capable of correctly detecting an impact applied to a side of a vehicle. <P>SOLUTION: A side airbag system 20 has pressure sensor units 23a-23d and an ECU 21, detects the impact at the time t2 based on the pressure P1 in a door at the time t1 based on the sensor signals output from the pressure sensor units 23a-23d and the pressure P2 in the door based on the sensor signal at the time t2 after the time t1, and transmits the control signals to airbag devices 25a-25d as control information. Since such information processing is performed exclusively by the ECU 21 capable of processing the input of the sensor signals to the output of the control signals within 10 msec, any microcomputer or the like capable of processing the operations, etc. of the sensor signals need not be provided on the pressure sensor units 23a-23d. The configuration of the pressure sensor unit 23a or the like can be simplified, the impact is correctly detected, and an increase in the product cost can be suppressed thereby. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle side collision detection device capable of detecting an impact applied to a side of a vehicle based on a pressure fluctuation in a vehicle door interior space.

  An example of a side collision detection device for a vehicle that can detect an impact applied to the side of the vehicle based on pressure fluctuations in the space inside the door of the vehicle is disclosed in Patent Document 1, for example. In this disclosed technique, when the door is strongly closed, an impact pressure increase similar to that at the time of a side collision can occur, and thus by performing predetermined signal processing based on pressure information from the air pressure sensor, It is possible to prevent a pressure increase due to a strong door closing or the like from being erroneously determined as a pressure increase due to a side collision. Specifically, in the case of a pressure increase at the time of non-collision due to strong closing of the door, attention is paid to the fact that the internal pressure of the door temporarily becomes negative before the pressure increase, and this negative pressure generation is controlled by an electronic control (ECU). By detecting the unit and performing predetermined signal processing, it is possible to distinguish between a pressure increase due to a strong door closing or the like and a pressure increase due to a side collision.

  By the way, in recent years, when such a side collision detection device for a vehicle is applied to a side airbag device, a side airbag is also applied to a rear seat in addition to a driver seat and a passenger seat at the time of a side collision of the vehicle. There is a demand that can be developed. For this reason, for example, as shown in FIG. 7, a plurality of pressure sensor units 123 a to 123 d and airbag devices 125 a to 125 d may be connected to the ECU 121 that controls the entire side airbag system 120. In the case of such a configuration, if the ECU 121 is caused to perform predetermined signal processing related to the negative pressure generation of the pressure sensor units 123a to 123d, the processing load on the ECU 121 increases. In many cases, the sensor ECU provided in the system performs the predetermined signal processing. Note that the ECU 121 includes a storage unit 121b and a communication I / F unit 121c that are connected via a system bus with the control unit 121a as a center.

  For example, when the fluctuation of the pressure detected by the pressure detection unit 123a1 constituting the pressure sensor unit 123a is detected based on the atmospheric pressure around the vehicle, the reference atmospheric pressure and the pressure detection unit 123a1 detect it. A function (computation block shown in FIG. 7) for comparing and calculating the measured pressure, a function for storing atmospheric pressure data in a semiconductor memory device (hereinafter referred to as “memory”) (memory block shown in FIG. 7), and pressure detection A function (filter block shown in FIG. 7) for removing electrical and mechanical noise that can be included in the pressure signal output from the unit 123a1 is also required for the pressure sensor unit 123a.

That is, in such a pressure sensor unit 123a, in addition to the pressure detection unit 123a1, a sensor ECU 123a3 having a control unit, a storage unit, an input / output interface unit, and the like is provided. Signal processing is enabled to reduce the processing load on the ECU 121 of the side airbag system 120. 7 is a signal amplifying unit capable of amplifying the pressure signal output from the pressure detecting unit 123a1. The pressure sensor units 123b, 123c, and 123d are configured in the same manner as the pressure sensor unit 123a.
JP-A-8-324379

  However, according to the side collision detection device for a vehicle applied to the side airbag system 120 as shown in FIG. 7, the pressure in the door space also varies depending on the atmospheric pressure. In order to measure the atmospheric pressure with high accuracy, it is necessary to correct the atmospheric pressure data corresponding to the altitude of the road or the like on which the vehicle is traveling with respect to the atmospheric pressure data serving as a reference. Therefore, if the signal processing described above is made possible for each of the pressure sensor units 123a to 123d, a memory device or the like that holds reference atmospheric pressure data, an arithmetic device that appropriately corrects, or the like is required. In addition to increasing the circuit size of the semiconductor chip that constitutes the ECU 123a3, the pressure sensor unit 123a and the like are increased in size, and the product cost is increased.

  Further, when the atmospheric pressure data is not held in such a memory device, the pressure information output from the pressure detection unit 123a1 is leveled over several seconds by separately providing a filter circuit having a relatively large time constant. It is possible to adopt a configuration in which the converted data is generated as atmospheric pressure data serving as a reference before the collision. However, in order to secure such a large time constant such as several seconds, it is necessary to configure a filter circuit with a capacitor having a large electrostatic capacity. Therefore, even if such a configuration is adopted, the pressure sensor unit 123a and the like itself In addition to the increase in size, there is a problem that the product cost increases.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a vehicle side collision detection device that can accurately detect an impact applied to the side of the vehicle. is there. Another object of the present invention is to provide a vehicle side collision detection device capable of suppressing an increase in product cost.

  In order to achieve the above object, in the vehicle side collision detection device according to claim 1 of the claims, the vehicle [10] is applied to the side of the vehicle [10] based on the pressure fluctuation in the door inner space. A vehicle side collision detection device capable of detecting an impact, the pressure detection means [23a] capable of detecting the pressure in the door inner space of one door [12a] and outputting pressure information, and the vehicle [10] The pressure information output from the pressure detection means [23a] can be acquired via the information transmission medium [27a] provided in the base, and based on the pressure information from the pressure detection means [23a] An information processing hand capable of detecting an impact at the time t2 based on the door internal pressure P1 at the time t1 and the door internal pressure P2 based on the pressure information at the time t2 after the time t1 and outputting it as detection information A [21], wherein the pressure the processable information processing means within 10 ms until the output of the detection information [21] from the input information, and technical features in that it comprises. The numbers in [] can correspond to the symbols described in the [Best Mode for Carrying Out the Invention] column (the same applies hereinafter).

  The side collision detection device for a vehicle according to claim 2 described in claim 2 is the vehicle side collision detection device according to claim 1, wherein the door of another door [12b] is different from the one door [12a]. Other pressure detection means [23b] capable of detecting the pressure of the inner space and outputting it as other pressure information is provided, and the other based on the other pressure information output from the other pressure detection means [23b] at the time t2. By replacing the door internal pressure P2 ′ with the door internal pressure P1 at the time t1, the information processing means [21] allows the other door internal pressure P2 ′ at the time t2 and the door internal pressure P2 at the time t2. A technical feature is that an impact at the time t2 can be detected based on the pressure P2 and output as a detection signal.

  The side collision detection device for a vehicle according to claim 3 according to claim 3 is the vehicle side collision detection device according to claim 1 or 2, wherein acceleration in a lateral direction of the vehicle [10] is detected to detect acceleration information. The information processing means [21] adds the acceleration information output from the acceleration detection means [24a] at the time t2 and outputs the vehicle [10] ], It is possible to detect the impact at the time t2 including the acceleration in the lateral direction and output it as a detection signal.

  In the first aspect of the invention, the pressure detection means [23a] and the information processing means [21] are provided, and the door internal pressure P1 at time t1 based on the pressure information output from the pressure detection means [23a], and the time t1 The impact at the time t2 is detected based on the pressure P2 in the door based on the pressure information at the later time t2, and the process from the input of the pressure information to the output of the detected information is processed within 10 milliseconds as the detected information. It is possible. Thereby, in the information processing means [21], for example, the fluctuation amount of the door internal pressure P2 at the time t2 can be detected on the basis of the door internal pressure P1 at the time t1 before the time t2. Information processing based on accurate pressure information is performed not by the pressure detection means [23a] but by the information processing means [21] capable of processing within 10 milliseconds from the input of the pressure information to the output of the detection information. There is no need to provide the pressure detection means [23a] with information processing means capable of processing information and the like. For this reason, while the structure of the pressure detection means [23a] can be simplified, the information processing based on the pressure information can be entrusted to the information processing means [21], so that the impact applied to the side of the vehicle [10] is reduced. It is possible to accurately detect and suppress an increase in product cost. Further, the pressure detecting means [23a] can be reduced in size.

  In the invention of claim 2, another pressure detection means [23b] capable of detecting the pressure in the door internal space of another door [12b] different from the one door [12a] and outputting as other pressure information, By replacing the other door pressure P2 ′ based on the other pressure information output at time t2 from the other pressure detection means [23b] with the door pressure P1 at time t1, the information processing means [21] Based on the other door pressure P2 ′ at time t2 and the door pressure P2 at time t2, the impact at time t2 can be detected and output as a detection signal. Thereby, for example, the fluctuation amount of the door internal pressure P2 at the time t2 can be detected on the basis of the other door internal pressure P2 ′ based on the other pressure information, so that the information processing means [21] It is not necessary to acquire the door internal pressure P1 at time t1 prior to time t2 or to store information regarding the acquired door internal pressure P1. For this reason, since the configuration of the information processing means [21] can be simplified in addition to the configuration of the pressure detection means [23a], the impact applied to the side of the vehicle [10] can be accurately detected and the product cost can be increased. Can be further suppressed.

  The invention according to claim 3 further includes acceleration detecting means [24a] capable of detecting lateral acceleration of the vehicle [10] and outputting it as acceleration information, and the information processing means [21] includes the acceleration detecting means [24a]. The acceleration information output at time t2 is added, and the impact at the time t2 including the lateral acceleration of the vehicle [10] based on the acceleration information can be detected and output as a detection signal. Thereby, not only the pressure information output from the pressure detection means [23a] and other pressure detection means [23b] but also the acceleration in the lateral direction of the vehicle [10] based on the acceleration information is included at the time t2. Since the impact can be detected, the impact applied to the side of the vehicle [10] can be detected more accurately. In addition, since the configuration of the pressure detection means [23a] and the acceleration detection means [24a] can be simplified as compared with the same scale, an increase in product cost can be suppressed.

  Hereinafter, an embodiment in which a vehicle side collision detection apparatus of the present invention is applied to a vehicle side airbag system will be described with reference to FIGS. 1A is a block diagram showing an example of a system configuration of a side airbag system 20 to which the vehicle side collision detection device of the present invention is applied, and FIG. 1B is a diagram showing how the pressure sensor unit 23a is attached. Explanatory drawing of the door 12a of the front right seat 17 which shows a position is each shown. FIG. 2 is a block diagram showing a configuration example of the side airbag system 20 according to the present embodiment, and FIGS. 3 and 4 are flowcharts showing control examples of the side airbag system. It is shown. 5 and 6 are a block diagram showing a side airbag system 20 ', which is another configuration example of the side airbag system 20, and a flowchart showing an example of control thereof.

First, the configuration of the side airbag system 20 will be described with reference to FIGS. 1 and 2.
As shown in FIG. 1A, the side airbag system 20 of the vehicle 10 mainly includes an ECU 21, pressure sensor units 23a, 23b, 23c, and 23d (hereinafter “pressure sensor units 23a to 23d”), an airbag device. 25a, 25b, 25c, 25d (hereinafter referred to as “airbag devices 25a to 25d”).

  As shown in FIG. 2, the ECU 21 is provided, for example, in the engine room of the vehicle 10, and includes a control unit 21a, a storage unit 21b, a communication I / F unit 21c, and the like. The ECU 21 has a function of detecting an impact applied to the side of the vehicle 10 based on pressure information obtained from the pressure sensor units 23a to 23d and sending control information to the airbag devices 25a to 25d. Therefore, a sensor signal (pressure information) is acquired from the pressure sensor units 23a to 23d connected to the in-vehicle LAN 27 via the communication I / F unit 21c, or the airbag devices 25a to 25d connected to the control line 28 are connected. A control signal (control information) can be transmitted. The control unit 21a can correspond to a microcomputer (CPU), the storage unit 21b can correspond to a semiconductor memory device (ROM, RAM), and the communication I / F unit 21c can correspond to a communication control unit (CCU).

  It should be noted that predetermined signal processing relating to the generation of negative pressure that can be individually performed by the conventional pressure sensor units 123a to 123d described in the section of “Background Art”, and an arithmetic block, a storage block, a filter block, and the like shown in FIG. In the present embodiment, each signal processing that can be performed is configured such that all signals can be processed by the ECU 21, and the ECU 21 receives an air bag device 25a from input of sensor signals from the pressure sensor units 23a to 23d, as will be described later. It has the information processing capability that can process the output of the control signal to ˜25d within 10 milliseconds.

  The pressure sensor units 23a to 23d are a pressure detection unit that is a semiconductor pressure sensor element such as a piezo type or a capacitance type that can detect the atmospheric pressure in the surrounding space, and a signal amplification that can amplify a sensor signal output from the pressure detection unit. For example, in the case of the pressure sensor unit 23a, the pressure sensor unit 23a1 includes a pressure detection unit 23a1 and a signal amplification unit 23a2.

  These pressure sensor units 23a to 23d are respectively provided in the door interior space of the side door of the vehicle 10 as shown in FIG. 1 (A). For example, as shown in FIG. The sensor unit 23a is mounted in the door 12a so as to be positioned at the approximate center of the door inner space formed by the door outer panel 11a and the door inner panel 11b constituting the door 12a of the front right seat 17. Similarly, the pressure sensor unit 23b is provided on the door 12b of the front left seat 18, the pressure sensor unit 23c is provided on the door 12c of the rear seat 19, and the pressure sensor unit 23d is provided on the door 12d of the rear seat 19. Each of the pressure sensor units 23a to 23d is configured to be able to perform data communication with the ECU 21 via the in-vehicle LAN 27.

  Note that these pressure sensor units 23a to 23d do not include a microcomputer, a microprocessor, or a digital signal processor that can process pressure information based on the sensor signals output from the pressure detection units 23a1 to 23d1. Regarding signal processing of signals, there is a feature in hardware configuration in that it only includes signal amplification units 23a2 to 23d2 that can perform signal amplification (current amplification, voltage amplification). Accordingly, the configuration of the pressure sensor units 23a to 23d can be simplified, and the size of the physique can be reduced and the cost of parts can be reduced.

  As shown in FIG. 1 (A), the air bag devices 25a to 25d are provided on the inner door sides of the front right seat 17, the front left seat 18, and the rear seat 19, respectively, by deploying the air bag. The vehicle 10 has a function of protecting passengers in the passenger compartment from an impact from the side of the vehicle 10. Specifically, as shown in FIG. 2, the air bag devices 25 a to 25 d are instantly triggered by the ignition device (not shown) that can be electrically connected to the ECU 21 via the control line 28, and the ignition by this ignition device. An inflator (not shown) capable of generating an inflation medium gas, an unillustrated airbag (not shown) that can be instantaneously deployed by the inflation medium gas, and the like.

  Next, a control example of the side airbag system 20 will be described with reference to FIGS. 3 and 4. FIG. 3 (A) shows a flowchart showing the flow of reference pressure data acquisition processing by the side airbag system 20, and FIG. 3 (B) shows the flow of impact detection processing by the side airbag system 20. A flowchart is shown. FIG. 4 shows a flowchart according to a modified example of the impact detection process. A program capable of executing a reference pressure data acquisition process, an impact detection process, and the like is stored in advance in the storage unit 21b (PROM or EEPROM) of the ECU 21, and the control unit 21a of the ECU 21 reads the program. These processes can be executed.

  First, the flow of the reference pressure data acquisition process shown in FIG. In this process, as will be described later, reference pressure data used for a predetermined calculation is acquired and stored as the door internal pressure P1 (atmospheric pressure) at time t1. Therefore, the process is started, for example, by a timer interrupt every predetermined time (for example, 5 milliseconds). Further, the impact detection process shown in FIG. 3B and the process may be alternately performed every predetermined time (for example, 5 milliseconds). As a result, the latest reference pressure (atmospheric pressure) data can be held.

  In step S101, a process of acquiring sensor signals (pressure information) from the pressure sensor units 23a to 23d is performed, and pressure information based on the acquired sensor signals is converted to the pressure sensor units 23a to 23d in step S103. Is stored in the storage unit 21b (RAM) of the ECU 21 as the corresponding reference pressure data (door pressure P1 at time t1). These reference pressure data correspond to atmospheric pressure data, and pressure information based on the reference pressure data is hereinafter simply referred to as “door pressure P1”.

  Thus, the door internal pressure P1 acquired by the reference pressure data acquisition process is used for the impact detection process shown in FIG. This impact detection process is also started by a timer interrupt every predetermined time (for example, 5 milliseconds), similar to the reference pressure data acquisition process, and every reference pressure data acquisition process and every predetermined time (for example, 5 milliseconds). You may process alternately.

  As shown in FIG. 3 (B), in the impact detection process, first, in step S201, a process of acquiring each sensor signal (pressure information) from each of the pressure sensor units 23a to 23d is performed. The pressure information based on these acquired sensor signals becomes the door pressure P2 at time t2, and is used for the subsequent ΔV calculation process in step S203.

  In step S203, the process which reads the door internal pressure P1 memorize | stored in the memory | storage part 21b (RAM) of ECU21 corresponding to each pressure sensor unit 23a-23d from the said memory | storage part 21b is performed. Then, after this step S203, the door internal pressure P1 (at time t1) for each of the pressure sensor units 23a to 23d read out, and the inside of the door for each of the pressure sensor units 23a to 23d acquired in step S201. A process of calculating ΔV based on the pressure P2 (at time t2 after time t1) is performed in step S205.

  ΔV calculated in step S205 is a volume change amount given by ΔV = V (P2−P1) / P1, and is obtained corresponding to each of the pressure sensor units 23a to 23d. That is, in this calculation formula, attention is paid to the fact that the volume of the door 12a and the like is reduced due to the impact caused by the collision from the side surface direction of the vehicle 10, and the volume change amount ΔV is calculated as the door pressure P1 at t1 before the collision. And the door internal pressure P2 at t2 after the collision. V is an initial volume in the door, that is, a volume in the door when there is no side collision, and is set to a predetermined value in advance.

  In step S207, it is determined whether the volume change amount ΔV calculated in step S205 has changed beyond a predetermined amount Vo. That is, in step S207, if the volume change amount ΔV exceeds the predetermined amount Vo (S207; Yes), it is determined (detected) that a side collision has occurred, and the process proceeds to step S209. If it does not exceed Vo (S207; No), it is determined that no side collision has occurred, and the impact detection process is terminated.

  When a side collision is detected in step S207 (S207; Yes), a process of sending a control signal (control information) to the corresponding airbag device in order to deploy the airbag device corresponding to the corresponding door in step S209. Done. For example, if a side collision is detected in step S207 based on the sensor signal from the pressure sensor unit 23a, a control signal that can deploy the airbag device 25a corresponding to the door 12a is sent to the airbag device 25a. Send to ignition device. Similarly, an air bag device 25b is used for a sensor signal from the pressure sensor unit 23a, an air bag device 25c is used for a sensor signal from the pressure sensor unit 23c, and an air sensor is used for a sensor signal from the pressure sensor unit 23d. A control signal is sent to each of the back devices 25d.

  Note that the impact detection process is based on the information processing capability of the ECU 21, and from the acquisition process of the pressure P2 in the door of the pressure sensor unit 23a and the like in step S201, the control signal (control information) of the airbag device 25a and the like is output in step S209 Since the process can be performed within 10 milliseconds or less (within), the above-described processes (S101, S103, S201, S203, S205, and S207) are not performed by the pressure sensor units 23a to 23d. . Thereby, since it is not necessary to have a microcomputer etc. in the pressure sensor units 23a-23d, the structure is simplified, the size of the physique is reduced, and the part cost is reduced.

  As described above, the side airbag system 20 according to the present embodiment includes the pressure sensor units 23a to 23d and the ECU 21, and the door at time t1 based on the sensor signals (pressure information) output from the pressure sensor units 23a to 23d. An impact at the time t2 is detected based on the internal pressure P1 and the door internal pressure P2 based on the sensor signal (pressure information) at time t2 after this time t1 (S207), and the control information (detection information) is detected. ) As a control signal to the airbag devices 25a to 25d. In addition, the process from the input of the sensor signal (pressure information) to the output of the control signal (control information, detection information) can be processed within 10 milliseconds.

  Thereby, the ECU 21 can detect the fluctuation amount of the door internal pressure P2 at the time t2 on the basis of the door internal pressure P1 at the time t1 before the time t2, for example. Information processing based on (information) is not performed by the pressure sensor units 23a to 23d, but exclusively by the ECU 21 capable of processing from input of sensor signals (pressure information) to output of control signals (control information, detection information) within 10 milliseconds By doing so, it is not necessary to provide the pressure sensor units 23a to 23d with a microcomputer or the like (information processing means) capable of processing the calculation of sensor signals (pressure information). For this reason, while the configuration of the pressure sensor units 23a to 23d can be simplified, the information processing based on the sensor signal (pressure information) can be entrusted to the ECU 21, so that the impact applied to the side of the vehicle 10 can be accurately detected. In addition, an increase in product cost can be suppressed. Further, the pressure sensor units 23a to 23d can be reduced in size.

  Next, a modified example of the impact detection process described above will be described with reference to FIG. In the modified example shown in FIG. 4, by replacing the other door internal pressure P2 ′ based on the sensor signal of the other door 12b and the like output at time t2, with the door internal pressure P1 at time t1, As described above, the impact at the time t2 can be detected based on the door internal pressure P2 ′ and the door internal pressure P2 at the time t2, and can be output as a control signal (detection signal) for the airbag device 25a and the like. This is different from the impact detection process shown in FIG. For this reason, substantially the same processing steps as those in the impact detection processing shown in FIG. 3B are denoted by the same reference numerals, and description thereof is omitted here.

  As shown in FIG. 4, in the modified example of the impact detection process, after the door internal pressure P2 is acquired in step S201, before or simultaneously with the reference pressure data acquisition process shown in FIG. When a door different from the door from which the pressure P2 is acquired, for example, the door internal pressure P2 is acquired from the door 12a, the door internal pressure P2 ′ of the other door 12b (or the door 12c or the door 12d) is used as the reference pressure data. As step S303. In the case of the door 12b, the door internal pressure P2 'is acquired based on the sensor signal from the pressure sensor unit 23b as in step S201.

  Thereby, since the fluctuation amount of the door internal pressure P2 at the time t2 can be detected based on the door internal pressure P2 ′, the ECU 21 acquires the door internal pressure P1 at the time t1 before the time t2. Or storing the acquired information on the door internal pressure P1. For this reason, since the structure of ECU21 can also be simplified, the impact added to the side of the said vehicle 10 can be detected correctly, and the raise of product cost can be suppressed further.

  In the flowchart shown in FIG. 4, for the convenience of the notation of the flowchart, the acquisition of the door internal pressure P2 ′ in step S303 is expressed after the acquisition of the door internal pressure P2 in step S201. The acquisition of the door internal pressure P2 ′ in step S303 may be before the acquisition of the door internal pressure P2 in step S201, or may be performed simultaneously if possible in the system configuration.

  Further, the door internal pressure P2 'obtained in step S303 may be obtained for a plurality of doors, for example, the doors 12b, 12c, and 12d, and the average value thereof may be used as the door internal pressure P2'. As a result, the door internal pressure P2 ′ acquired as the reference pressure data becomes data based on the door internal pressure obtained from the plurality of pressure sensor units. Therefore, compared to the case where the data is obtained from one pressure sensor unit, Measurement accuracy can be improved.

Subsequently, as another configuration example of the side airbag system 20 described above, a configuration and the like of the side airbag system 20 ′ will be described with reference to FIGS.
As shown in FIG. 5, the side airbag system 20 ′ described here includes G sensor units 24 a and 24 b in addition to the pressure sensor units 23 a to 23 d and is detected by these G sensor units 24 a and the like. The impact at time t2 can be detected including the acceleration information based on the lateral acceleration of the vehicle 10. For this reason, about the structure etc. which are substantially the same as the side airbag system 20 mentioned above, the same code | symbol shall be attached | subjected in FIG. 5 and FIG. 6, and those description is abbreviate | omitted.

  As shown in FIG. 5, the G sensor units 24a and 24b are acceleration detection units 24a1 that are piezo-type and capacitive-type semiconductor acceleration sensor elements capable of detecting acceleration applied in the lateral direction (width direction) of the vehicle 10. 24b1 and signal amplifiers 24a2 and 24b2 capable of amplifying sensor signals output from the acceleration detectors 24a1 and 24b1. These G sensor units 24a and 24b are front and rear side doors of the vehicle 10 (for example, the doors 12a and 12c shown in FIG. 1A if the G sensor unit 24a is used, and the doors if the G sensor unit 24a is used. 12b and the door 12d) are attached to a center pillar, and are configured to be able to communicate data with the ECU 21 via the in-vehicle LAN 27, respectively.

  As a result, the ECU 21 can acquire sensor signals (acceleration information) output at time t2 from the G sensor units 24a and 24b. For example, the sensor signals output from the pressure sensor units 23a to 23d Detecting the impact at the time t2 including the lateral acceleration of the vehicle 10 based not only on the pressure information based on it but also on acceleration information based on sensor signals output from the G sensor units 24a, 24b. Can do. Specifically, the flow of the collision detection process is shown in FIG. 6, and the outline of the collision detection process will now be described with reference to FIG.

  As shown in FIG. 6, in the collision detection process related to the side airbag system 20 ′, each pressure sensor unit 23 a-is executed in step S <b> 201 in the same manner as the collision detection process of the side airbag system 20 described with reference to FIG. 4. After performing the process of acquiring the door internal pressure P2 based on the sensor signal output from 23d, the process of acquiring the door internal pressure P2 ′ of another door at time t2 is performed in step S303. Then, after calculating the volume change amount ΔV in step S205, it is determined whether or not a side collision has occurred in step S207.

  If it is determined in step S207 that a side collision has been detected (S207; Yes), in step S401, the door side G sensor unit 24a provided with the pressure sensor unit 23a or the like that outputs a sensor signal related to the collision is provided. (Or G sensor unit 24b) obtains acceleration information based on the sensor signal, that is, acceleration G, and further determines whether or not the obtained acceleration G exceeds a predetermined value Go in step S403. Processing is performed. If the acceleration G exceeds the predetermined value Go (S403; Yes), a control signal is sent to the corresponding airbag device 25a or the like in step S209, and if it does not exceed (S403; No). ) Ends the collision detection process without sending a control signal to the airbag device 25a or the like.

  That is, even if it is determined in step S207 that a side collision has occurred, a control signal is not immediately sent to the corresponding airbag device 25a or the like as in the collision detection process shown in FIG. FIG. 3 (B), FIG. 4; S209), determination of whether or not an impact due to a collision has occurred on the side surface of the vehicle 10 based on the acceleration G (acceleration information) based on the sensor signal from the corresponding G sensor unit 24a or the like. Therefore, the impact applied to the side of the vehicle 10 can be detected more accurately than when the impact is detected based only on the sensor signals from the pressure sensor units 23a to 23d.

  Note that the process of acquiring the acceleration G in step S401 is configured to be performed before the process of determining ΔV> Vo in step S207 (for example, between steps S201 and S303 or between steps S303 and S205). May be. Accordingly, the acceleration G magnitude determination process in step S403 can be performed immediately after the determination process in step S207, so that the processing speed can be improved.

FIG. 1 (A) is a configuration diagram showing a system configuration example of a side airbag system to which the vehicle side collision detection device of the present invention is applied, and FIG. 1 (B) is a front right side showing a mounting position of the pressure sensor unit. It is explanatory drawing of the door of a seat. It is a block diagram which shows the structural example of the side airbag system which concerns on this embodiment. FIG. 3A is a flowchart showing a control example of the side airbag system, FIG. 3A shows a flow of reference pressure data acquisition processing, and FIG. 3B shows a flow of impact detection processing. It is a flowchart which shows the other example of control of this side airbag system, and shows the flow of the impact detection process by a modification. It is a block diagram which shows the other structural example of this side airbag system. FIG. 6 is a flowchart showing a control example of the side airbag system shown in FIG. 5 and shows a flow of impact detection processing. It is a block diagram which shows the structural example of the side airbag system corresponded to the example of application of the conventional side collision detection apparatus for vehicles.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Vehicle 11a ... Door outer panel 11b ... Door inner panel 12a ... Door (one door)
12b, 12c, 12d ... Doors (other doors)
17 ... Front right seat 18 ... Front left seat 19 ... Back seat 20, 20 '... Side airbag system (side collision detection device for vehicle)
21 ... ECU (information processing means)
21a ... Control unit 21b ... Storage unit 21c ... Communication I / F unit 23a ... Pressure sensor unit (pressure detection means)
23b, 23c, 23d ... Pressure sensor unit (other pressure detection means)
23a1, 23b1, 23c1, 23d1 ... Pressure detection unit 23a2, 23b2, 23c2, 23d2 ... Signal amplification unit 24a, 24b ... G sensor unit (acceleration detection means)
24a1, 24b1 ... Acceleration detection unit 24a2, 24b2 ... Signal amplification unit 25a, 25b, 25c, 25d ... Airbag device 27 ... In-vehicle LAN (information transmission medium)
28 ... Control line

Claims (3)

A vehicle side collision detection device capable of detecting an impact applied to a side of the vehicle based on pressure fluctuations in a vehicle door inner space,
Pressure detection means capable of detecting pressure in the door space of one door and outputting pressure information;
The pressure in the door at time t1 based on the pressure information from the pressure detection means is configured to be able to acquire the pressure information output from the pressure detection means via an information transmission medium provided in the vehicle. Information processing means capable of detecting an impact at the time t2 based on P1 and the pressure P2 in the door based on the pressure information at the time t2 after the time t1, and outputting the detected information as detection information. Information processing means capable of processing within 10 milliseconds from the input to the output of the detection information;
A vehicle side collision detection apparatus comprising:   Other pressure detection means capable of detecting the pressure in the door internal space of another door different from the one door and outputting as other pressure information is provided, and the other pressure output from the other pressure detection means at the time t2 By replacing the other door internal pressure P2 ′ based on the pressure information at the time t1 with the door internal pressure P1 at the time t1, the information processing means can detect the other door internal pressure P2 ′ at the time t2 and the time t2. 2. The side collision detection device for a vehicle according to claim 1, wherein the impact at the time t2 can be detected based on the door internal pressure P2 and output as a detection signal.   Acceleration detecting means capable of detecting lateral acceleration of the vehicle and outputting it as acceleration information is provided, and the information processing means adds the acceleration information output from the acceleration detecting means at the time t2, and based on this 3. The side collision detection apparatus for a vehicle according to claim 1, wherein an impact at time t2 including the acceleration in a lateral direction of the vehicle can be detected and output as a detection signal.

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