JP2011196772A - Side collision sensor for vehicle, side collision detection system for vehicle, and occupant-restraint system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique effective for simplifying the structure of a side collision sensor for a vehicle, and enhancing its detection accuracy.SOLUTION: The side collision sensor includes a sensor housing; a detecting coil 130a which is housed in the sensor housing so as to extend in the front and rear directions of the vehicle, and into which an alternating current is caused to flow; a rotating shaft 141 which is housed in the sensor housing and extends side by side with the detecting coil 130a, in the front and rear directions of the vehicle; an inertial mass body 140 allowed to rotate around the rotating shaft 141 on a rotation plane which crosses the coil extension plane of the detecting coil 130a; a part to be detected which is conductive and is provided in the inertial mass body 140 so as to face the detecting coil 130a, and whose distance from the detecting coil 130a changes with the rotation of the inertial mass body 140; an output part for outputting information on the rotation, based on a change in the impedance of the detecting coil 130a generated by a change in the distance between the detecting coil 130a and the part to be detected, when the inertial mass body 140 rotates.

Description

  The present invention relates to a technique for detecting information related to a side collision of a vehicle.

Conventionally, various vehicle collision sensors that detect occurrence of a collision in the event of a vehicle accident are known. For example, Patent Document 1 below discloses a side collision sensor that detects a side collision of a vehicle using a detection sensor that combines a detection coil and a permanent magnet.
By the way, when designing this type of side collision sensor using a detection sensor including a detection coil, there is a technology that simplifies the structure without using a complicated mechanism or electronic component, and improves the detection accuracy of the sensor. It is desired.

JP-A-8-113108

  Therefore, the present invention has been made in view of the above problems, and in a vehicle side collision sensor that detects information related to a side collision of a vehicle using a detection coil, the structure is simplified and the detection accuracy is improved. It is an object to provide an effective technique for this.

  The present invention is configured to solve the above problems. The present invention is typically applicable to a technique for detecting information related to a side collision occurring in an automobile, but similarly to a technique for detecting information relating to a side collision occurring in a vehicle other than an automobile. The present invention can be applied. The “vehicle” herein includes various vehicles such as automobiles, aircraft, ships, trains, buses, and trucks.

  The vehicle side collision sensor according to the present invention is configured as a sensor that is activated by a side collision of the vehicle. The vehicle side collision sensor includes a sensor housing, a detection coil, a rotating shaft, an inertial mass body, a detected portion, and an output portion.

  The sensor housing is disposed in a partition area partitioned by a door outer panel and a door inner panel of the vehicle door. The sensor housing is typically installed in a long shape between the door front end portion and the door rear end portion of the vehicle door, and bends inwardly with the displacement of the door outer panel at the time of a vehicle side collision. Attached to a construction member (also referred to as “door beam” or “reinforcing member”). As a member other than the erection member, a sensor housing may be attached to a door frame or a door inner panel of a vehicle door.

  The detection coil is housed in the sensor housing so as to extend in the vehicle front-rear direction, and is configured as a coil through which an alternating current is passed. This detection coil is configured as a circular coil in which the winding is wound one or more times. The rotating shaft is accommodated in the sensor housing and extends in the vehicle front-rear direction in parallel with the detection coil.

  The inertia mass body is configured as a mass body that is allowed to rotate on a rotation plane that intersects the coil extension surface of the detection coil with the rotation axis as a center. The detected portion is provided on the inertial mass body so as to face the detection coil, and is configured as a conductive portion whose distance from the detection coil can be changed in accordance with the rotation operation of the inertial mass body. Typically, a conductor or a magnetic material including steel, copper, aluminum, ferrite, or the like is used as the detected portion. The detected portion may be constituted by all or part of the inertial mass body, or may be constituted by a member separate from the inertial mass body.

  The output unit functions to output information related to the rotation operation of the inertial mass body based on a change in impedance of the detection coil caused by a change in the distance between the detection coil and the detected portion during the rotation operation of the inertial mass body. The “information relating to the rotation operation of the inertial mass body” herein includes a rotation angle, a rotation angular velocity, a rotation angle acceleration, a rotation amount, and the like during the rotation operation of the inertial mass body. In this vehicle side collision sensor, the inertial mass body has a predetermined rotation plane (W) while maintaining the relative positional relationship between the rotation axis of the inertial mass body and the detection coil regardless of the side collision mode of the vehicle door. A rotational motion of the inertial mass body is detected by the detection coil.

  According to the above-described configuration of the vehicle side collision sensor, the configuration is mainly composed of the detection coil and the inertial mass body having the detected portion, so that the structure is simplified without excessively using complicated mechanisms or electronic components. It is effective to make it. In addition, this vehicle side collision sensor is a non-contact type using a detection coil, and has a characteristic such as being hardly affected by the surrounding environment because it is strong against shock and does not react to the shock. Since the detection sensor detects the detected portion of the inertial mass body that rotates on the orbit of the rotation plane, it is effective to improve the detection accuracy of the rotational operation mode of the inertial mass body.

  Further, according to the above configuration of the vehicle side collision sensor, even if the inertia mass body rattles in the direction along the extending direction of the rotating shaft, the detection coil is detected in the direction intersecting the extending direction of the rotating shaft. It is possible to prevent the detection accuracy of the detected portion by the detection coil from being lowered due to the fact that the distance between the inertial mass body and the inertial mass body is hardly affected.

  In a further embodiment of the vehicle side collision sensor according to the present invention, the detected portion is configured such that the extending width in the extending direction of the rotating shaft exceeds the coil diameter of the detecting coil, and the extending width of the detected portion. It is preferable that the detection coil is arranged inside. According to such a configuration, even if the inertia mass body rattles in the direction along the extending direction of the rotating shaft, it is possible to prevent the detected portion from coming off the detection area of the detection coil. Thus, it is effective to ensure the desired detection accuracy of the detected part by the detection coil.

  In a further embodiment of the vehicle side collision sensor according to the present invention, it is preferable that the detected portion is constituted by the outer peripheral surface of the inertia mass body. With regard to this configuration, a detected part separate from the inertial mass body may be attached to the outer peripheral surface of the inertial mass body, or the entire inertial mass body may be configured as the detected part. According to such a configuration, the structure of the vehicle side collision sensor can be further simplified.

In a further aspect of the vehicle side collision sensor according to the present invention, the inertial mass body elastically biases the inertial mass body so as to rotate when an acceleration exceeding a preset acceleration is applied to the sensor housing. It is preferable that the configuration includes a member. Typically, a coil spring, a leaf spring, or the like can be used as the elastic member. In the present invention, the acceleration sensor that detects the acceleration acting on the sensor housing may be a constituent requirement of the vehicle side collision sensor.
According to such a configuration, it is possible to prevent the vehicle side collision sensor from being activated by the elastic member when a minor side collision occurs in which the door outer panel of the vehicle door hardly displaces or deforms. It becomes.

In a further aspect of the vehicle side collision sensor according to the present invention, the sensor mass housing includes a single sensor module in which the inertia mass body and the detection sensor are integrally assembled and fixed to the sensor housing, and the sensor module is a vehicle door. It is preferable that it is the structure attached to a side member via an attachment bracket. As the “vehicle door side member” here, typically, the above-described installation member, a door frame of a vehicle door, a door inner panel, or the like is employed.
According to such a configuration, a single sensor module in which the inertia mass body and the detection sensor are integrally assembled can be attached to the vehicle door side member together with the sensor module. In contrast, it is possible to construct a highly versatile side collision sensor.

A vehicle side collision detection system according to the present invention is a system that detects information related to a side collision of a vehicle, and includes at least a vehicle side collision sensor and a determination unit that determines a side collision mode of a vehicle door. It is said. In particular, the determination unit is configured to determine the side collision mode of the vehicle door based on information output from the output unit of the vehicle side collision sensor. Typically, the side collision that has occurred by this determination unit is a collision that is highly necessary to immediately restrain the vehicle occupant, or a minor collision that is less necessary or unnecessary to restrain the vehicle occupant immediately. In addition, it is determined whether the generated side collision is a collision related to a road or roadside object, or a collision other than a collision related to a road or roadside object. The information on the side collision mode of the vehicle determined by the determination unit includes control of an occupant restraint device such as an airbag module or a seat belt device that operates to restrain the vehicle occupant in the case of a side crash of the vehicle, It is appropriately used for control of a notification device that performs display output and voice output to perform notification of a collision, and control of other control targets.
According to the vehicle side collision detection system having such a configuration, it is possible to appropriately determine the side collision mode of the vehicle door by the determination unit by using the detection information of the vehicle side collision sensor with high detection accuracy. Become.

The occupant restraint system according to the present invention includes at least the vehicle side collision detection system, the occupant restraint device, and the control device. The occupant restraint device is configured as a device that restrains the vehicle occupant during a side collision of the vehicle. As the “occupant restraint device” here, typically, an airbag device (airbag module) that restrains an occupant with an airbag that is deployed and inflated in the occupant restraint region, or a chest or abdomen of an occupant seated on a vehicle seat An occupant restraint device such as a seat belt device that restrains via a belt is included. In this case, when an airbag device is used as the occupant restraint device, an airbag device in which the airbag is accommodated in a seat, a pillar, an upper roof rail, or the like can be employed. The control device is configured as a device having at least a function of driving and controlling the occupant restraint device based on information determined by the determination unit of the vehicle side collision detection system, that is, a collision mode at the time of a side collision of the vehicle. Typically, a configuration in which a drive control signal is output to an airbag device or a seat belt device when the determination unit determines that the generated side collision is a collision that is highly necessary to immediately restrain the vehicle occupant. Can be adopted. The control device may be configured exclusively for controlling the occupant restraint device, or may be configured to serve as a means for driving and controlling the vehicle engine traveling system and the electrical system.
According to the occupant restraint system having such a configuration, the occupant restraint device is controlled using appropriate information determined by the determination unit of the vehicle side collision detection system. It is done.

Moreover, in the further form of the passenger | crew restraint system concerning this invention, it is further provided with the acceleration sensor which detects the information regarding the acceleration which acts on a vehicle, and a control apparatus is the information determined in the determination part of the side collision detection system, and It is preferable that the occupant restraint device be driven and controlled based on both of the information detected by the acceleration sensor. Typically, when the movement amount and movement speed of the pendulum member are relatively high and the acceleration acting on the vehicle exceeds a predetermined value, the generated side collision needs to immediately restrain the vehicle occupant. A configuration in which the occupant restraint device is driven and controlled for high collision can be used.
According to the occupant restraint system configured as described above, the occupant restraint device is driven and controlled under more appropriate conditions based on both the information determined by the determination unit of the side collision detection system and the information detected by the acceleration sensor. It becomes possible to do.

  As described above, according to the present invention, it is possible to simplify the structure and improve the detection accuracy in the vehicle side collision sensor that detects information related to the side collision of the vehicle using the detection coil.

1 is a diagram showing a schematic configuration of an occupant restraint system 100 of the present embodiment. It is a figure which shows the attachment position of the side collision sensor 130 in the said vehicle door in the side view of the vehicle door. It is a figure which shows the cross-section regarding the arrow AA of the vehicle door 10 in FIG. It is a disassembled perspective view of the side collision sensor 130 of this Embodiment. FIG. 5 is a perspective view of a detection coil 130a and an inertial mass body 140 in FIG. 6 is a plan view of a detection coil 130a and an inertial mass body 140 in FIG. In occupant restraint system 100 of the present embodiment, it is a diagram schematically showing a cross-sectional structure before a vehicle door 10 collides sideways with a colliding object 200. FIG. It is a figure which shows typically the cross-sectional structure at the time of the side collision with respect to the collision object 200 of the vehicle door 10 in FIG. It is a figure which shows typically the mode at the time of the action | operation of the side collision sensor 130 of this Embodiment. It is a figure which shows the characteristic of the shape of the inertial mass body 140 of this Embodiment.

  Hereinafter, an occupant restraint system 100 according to an embodiment of the “occupant restraint system” of the present invention will be described. The occupant restraint system 100 has a function of suitably restraining a vehicle occupant riding in the own vehicle when the own vehicle collides with another vehicle or a collision object other than the vehicle from the side. Specifically, an airbag module having an airbag that can be deployed and inflated to an occupant restraint region on the side of the occupant is employed as the restraining means.

  FIG. 1 is referred to regarding the schematic configuration of the occupant restraint system 100 of the present embodiment. The occupant restraint system 100 is typically a system mounted on an automobile (vehicle), and is roughly divided into an acceleration sensor 110, a side collision sensor 130, an ECU 150, and an airbag module 170 as shown in FIG. Is done. This occupant restraint system 100 can be applied as a system for restraining a vehicle occupant seated in a driver seat, a passenger seat, a rear seat, or the like. Although not specifically shown, the vehicle on which the occupant restraint system 100 is mounted includes, in addition to the occupant restraint system 100, a number of vehicle constituent members that constitute the vehicle, an engine, and an engine that is a system involved in traveling of the vehicle. The vehicle includes a traveling system, an electrical system that is a system related to electrical parts used in the vehicle, an engine traveling system, a drive control device that performs drive control of the electrical system, and the like.

  The acceleration sensor 110 is configured as an acceleration sensor that detects at least information related to acceleration in the Y-axis direction among the accelerations in the three-axis (X-axis, Y-axis, and Z-axis) directions acting on the vehicle. The acceleration information S10 detected by the acceleration sensor 110 is output to the CPU 152 constituting the ECU 150. Typically, the acceleration sensor 110 is preferably attached to the left and right B pillars of the vehicle. The acceleration sensor here corresponds to the “acceleration sensor” in the present invention.

  The side collision sensor 130 is configured as a detection sensor that operates in accordance with the displacement (also referred to as “deformation” or “movement”) of the door outer panel that occurs during a side collision of the vehicle. The side collision sensor 130 is typically attached to each of a door beam or a reinforcing member attached to the left and right vehicle doors. The side collision sensor 130 includes a detection coil 130a and an ASIC 130b as an IC chip (semiconductor) used for control and signal processing of the detection coil 130a. Based on the detection of a predetermined inertial mass body (also referred to as a “target”) by the detection coil 130a, the ASIC 130b outputs a detection information S20 indicating the rotational operation mode of the inertial mass body to the CPU 152, or the side collision sensor 130. It fulfills the function of performing fault diagnosis. If necessary, a configuration in which the functions of the ASIC 130b are collectively performed by the CPU 152 may be employed. The side collision sensor 130 here corresponds to the “vehicle side collision sensor” in the present invention.

  ECU 150 is configured as a control mechanism that performs drive control of at least airbag module 170, and includes at least CPU 152. The CPU 152 (ECU 150) detects the vehicle door based on the acceleration information S10 output from the acceleration sensor 110 and the detection information S20 of an inertial mass body (an inertial mass body 140 described later) output from the side collision sensor 130 (ASIC 130b). The side collision mode is determined, and the drive control signal S30 is output to the airbag module 170. Therefore, the CPU 152 is configured to determine the side collision mode of the vehicle door based on at least the operation mode of the inertial mass detected by the detection unit (a detection coil 130a described later) of the side collision sensor 130. The “determination unit” in FIG.

  The ECU 150 here is a control device that drives and controls the airbag module 170, and corresponds to the “control device” in the present invention. The ECU 150 may be configured as a control device that drives and controls only the airbag module 170, or in addition, as a part of a control unit as a drive control device that controls the engine running system and the electrical system of the vehicle. It may be configured. The system constituted by the ECU 150 and the side collision sensor 130 is a side collision detection system that detects information related to a side collision of the vehicle, and constitutes the “vehicle side collision detection system” in the present invention.

  The airbag module 170 includes at least a gas supply device 172 and an airbag 174. The airbag 174 is formed into a bag shape with a fabric, and is configured as a member that can be expanded and contracted. The gas supply device 172 includes an inflator as a gas generator for deployment and inflation gas, and a guide member that guides the deployment and inflation gas generated by the inflator into the airbag 174. The airbag 174 is configured to be deployed and inflated into the occupant restraint region by the supply of the deployment and inflation gas from the gas supply device 172 when the gas supply device 172 is operated based on the drive control signal S30 output from the ECU 150. Is done. Thereby, in the event of a vehicle accident, it is possible to control to restrain the vehicle occupant via the airbag 174 of the airbag module 170. The airbag module 170 here is configured as a device that restrains a vehicle occupant in the event of a side collision of the vehicle, and corresponds to the “occupant restraint device” and “control target” in the present invention.

  In this occupant restraint system 100, the occupant restraint device that is driven and controlled by the drive control signal e from the ECU 150 uses an occupant restraint device different from the airbag module 170 instead of or in addition to the airbag module 170. It is possible. As an occupant restraint device separate from the airbag module 170, typically, an occupant restraint device such as a seat belt device, or a notification device that performs display output or audio output to perform notification of a vehicle side collision or the like can be used. .

  2 and 3 are referred to regarding the configuration of the side collision sensor 130 and its peripheral parts. FIG. 2 is a view showing a mounting position of the side collision sensor 130 in the vehicle door 10 in a side view, and FIG. 3 shows an arrow A- of the vehicle door 10 in FIG. A cross-sectional structure with respect to line A is shown. In these drawings and drawings to be described later, the first direction indicated by the arrow FR indicates the front of the vehicle (the forward direction), the second direction indicated by the arrow UP indicates the vehicle upper direction, and the third direction indicated by the arrow IN. Indicates the inside of the vehicle (vehicle compartment direction).

  As shown in FIGS. 2 and 3, the vehicle door 10 for passenger entry / exit is connected to a vehicle body (also referred to as “vehicle body” or “vehicle body”) 17 via a door hinge 16. A door outer panel 11 forming an outer side wall and a door inner panel 12 forming an inner side wall of the vehicle are provided. The vehicle door 10 may be configured as a front seat door installed between the A pillar and the B pillar of the vehicle, or may be configured as a rear seat door installed between the B pillar and the C pillar. May be. In the partition region 13 partitioned by the door outer panel 11 and the door inner panel 12, a door beam 20 extending in the longitudinal direction in the vehicle longitudinal direction (also referred to as “first direction along the arrow FR”) is installed. ing. In the present embodiment, the side collision sensor 130 is configured to be attached to the door beam 20 via the attachment bracket 21. If necessary, the side collision sensor 130 may be attached to an attachment location other than the door beam 20, for example, an attachment location of the door inner panel 12 or the door frame. The vehicle door 10, the door outer panel 11, the door inner panel 12, the partition region 13, the door beam 20, and the mounting bracket 21 referred to here are “vehicle door”, “door outer panel”, “door inner panel”, “partition” in the present invention, respectively. It corresponds to “region”, “vehicle door side member” and “mounting bracket”.

  The door beam 20 is a cylindrical, rod-shaped or columnar member extending in the longitudinal direction in the vehicle front-rear direction along the first direction. One end of the door beam 20 is fixed to the vehicle main body 17 via the vehicle front side bracket 14, while the other end of the door beam 20 is fixed to the vehicle main body 17 via the vehicle rear side bracket 15. . That is, the door beam 20 is provided between the door front end (vehicle front side bracket 14) and the door rear end (vehicle rear side bracket 15) in the vehicle longitudinal direction with both ends corresponding to the brackets 14 and 15 as fixed ends. It is erected in a long shape. In such a configuration, the door beam 20 performs a bending operation toward the inside of the vehicle, that is, an operation of deforming into a bow shape in accordance with the displacement of the door outer panel 11 at the time of a side collision of the vehicle. One or more door beams 20 are installed in the vertical direction of the door along the second direction at a position close to the door outer panel 11 in the partition region 13 of the vehicle door 10.

  4 to 6 are referred to for a specific configuration of the side collision sensor 130. FIG. Here, FIG. 4 shows an exploded perspective view of the side collision sensor 130 of the present embodiment. 5 is a perspective view of the detection coil 130a and the inertial mass body 140 in FIG. 4, and FIG. 6 is a plan view of the detection coil 130a and the inertial mass body 140 in FIG. Yes.

  As shown in FIG. 4, the side collision sensor 130 of this embodiment includes a base member 132 that is fixed to the mounting bracket 21 via a bush 131. The base member 132 includes side walls 132a and 132a, a housing space 132b, mounting holes 132c and 132c, and a connector 133. The side wall portions 132a and 132a are a pair of left and right side wall portions facing each other in the base member 132, and define an accommodation space 132b for accommodating the coil holder 136 holding the detection coil 130a.

  Each side wall 132a is provided with a mounting hole 132c. The mounting hole 132c functions to support the inertial mass body 140 on the base member 132 via the shaft member 141 so as to be rotatable. Specifically, a shaft member 141 having an outer diameter slightly smaller than the inner diameter of the through hole 140a is passed through the through hole 140a of the inertia mass body 140, and both end portions of the shaft member 141 are attached to the mounting holes 132c and 132c. After the insertion, the clip 142 is engaged with the groove 141 a extending in the circumferential direction of the shaft member 141, whereby the inertia mass body 140 is supported by the base member 132. The connector 133 functions as a connection unit that connects the detection coil 130a to the ECU 150 described above.

  A sensor cover 135 is attached to the base member 132. The sensor cover 135 functions to cover the entire detection coil 130a and the inertial mass body 140 accommodated in the accommodation space 132b. The sensor cover 135 is disposed in the partition region 13 of the vehicle door 10 together with the base member 132, and constitutes a sensor housing that houses the detection coil 130a and the inertia mass body 140. Therefore, the sensor cover 135 and the base member 132 referred to here constitute a “sensor housing” in the present invention.

  In the present embodiment, a shield member 134 is provided on the inner surface of the sensor cover 135. The shield member 134 is preferably made of a metal that is not easily affected by a magnetic field, for example, iron. According to such a configuration, since the periphery of the detection coil 130a accommodated in the accommodation space 132b is covered with the shield member 134, the magnetic field existing outside the side collision sensor 130, specifically, mounted on the vehicle It is possible to obtain the effect of being resistant to magnetic field noise and being resistant to the influence of magnetic fields from components or magnetic fields existing outside.

  The inertial mass body 140 is configured as a mass portion (mass). As shown in FIGS. 5 and 6, the inertial mass body 140 is formed in the left-right direction (third direction) intersecting the vehicle front-rear direction (second direction). On the rotation plane A1 extending in the direction of the arrow), and rotating or swinging in a pendulum manner in the directions of the arrows 30 and 32 around the shaft member 141 extending in the vehicle front-rear direction in parallel with the detection coil 130a. Operation is allowed. The inertia mass body 140 is also referred to as a “pendulum member”, “swing member”, or “rotating member”. An outer peripheral surface 140b of the inertial mass body 140 is a facing surface provided on the inertial mass body 140 so as to face the detection coil 130a, and is a detection target (also referred to as a “target”) that is substantially detected by the detection coil 130a. ), Typically, a conductor or magnetic material including steel, aluminum, ferrite, or the like is used. The distance between the outer circumferential surface 140b and the detection coil 130a is variable as the inertial mass body 140 rotates, and in particular, as the inertial mass body 140 approaches the detection coil 130a, the outer circumferential surface 140b and the detection coil 130a. The distance between and is gradually reduced. Accordingly, the outer peripheral surface 140b corresponds to the “inertial mass body” in the present invention, and the outer peripheral surface 140b of the inertial mass body 140, that is, the inertial mass body 140 itself is used in the present invention. A “conductive portion to be detected” is configured.

  In addition, in order to further simplify the structure of the side collision sensor 130, the outer peripheral surface 140b of the inertial mass body 140 is formed of a conductor or a magnetic material as in the present embodiment, and the inertia including the outer peripheral surface 140b. The entire mass body 140 is preferably made of the same conductor or magnetic body as the outer peripheral surface 140b. In this case, the inertial mass body 140 and the outer peripheral surface 140b may have an integral structure or may have separate structures that can be separated from each other.

  The inertia mass body 140 is attached with a coil spring 143 (also referred to as “coil spring”) that elastically biases the inertia mass body in the direction of arrow 32. The coil spring 143 is configured as a spring member that is spirally wound around the shaft member 141. The coil spring 143 is inertial in a low acceleration state in which acceleration (for example, acceleration input in the direction of the arrow 34 in FIGS. 5 and 6) acting on the side collision sensor 130 at the time of a side collision of the vehicle door 10 is relatively low. While preventing the mass body 140 from rotating in the direction of the arrow 30 in the high acceleration state in which the acceleration exceeding the acceleration in the low acceleration state acts on the sensor housing (the base member 132 or the sensor cover 135) of the side collision sensor 130, It has a resilience that allows the inertial mass 140 to rotate in the direction of arrow 30. That is, the coil spring 143 is configured so that the inertial mass body 140 rotates only in the direction of the arrow 30 only when an acceleration exceeding a predetermined predetermined acceleration acts on the sensor housing of the side collision sensor 130. The spring 140 applies an elastic biasing force in the direction of arrow 32 to the body 140. According to this coil spring 143, it is possible to prevent the side collision sensor 130 from operating when a minor side collision occurs such that the door outer panel 11 of the vehicle door 10 hardly displaces or deforms at all. Become. The coil spring 143 here corresponds to an “elastic member” in the present invention.

  On the other hand, the detection coil 130a is disposed so as to extend in the vehicle front-rear direction on a coil extension plane A2 that intersects (typically orthogonal) the rotation plane A1 of the inertial mass body 140. The detection coil 130a is configured as a circular coil in which a winding is wound one or more times, and has a characteristic that impedance changes according to the state of an external magnetic field (detected magnetic field). The detection coil 130a is connected to an AC power supply device (not shown) included in the ASIC 130b, and an AC current (sine wave current) is energized by driving the AC power supply device, whereby the detection coil 130a is supplied with an AC current. Magnetic field is generated. This detection coil 130a is also referred to as a “conductive coil” through which an alternating current is conducted.

  By the way, when detecting this type of detection coil, there is a concern that rattling when the inertial mass body detected by the detection coil affects the detection accuracy of the inertial mass body. In the case of inertial mass body 140 according to the present embodiment, inertial mass body 140 in a direction in which the backlash of inertial mass body 140 in the direction along the extending direction of shaft member 141 intersects the extending direction of shaft member 141. It is assumed that it exceeds the backlash. Therefore, the present embodiment has the following two characteristic points regarding the relative positional relationship between the detection coil 130a and the inertial mass body 140.

  As a first feature point, the rotation plane A1 of the inertial mass body 140 and the coil extension plane A2 of the detection coil 130a intersect each other. According to such a configuration, even if rattling of the inertial mass body 140 occurs in a direction along the extending direction of the shaft member 141, the inertia of the detection coil 130 a and the inertia in the direction intersecting the extending direction of the shaft member 141. The distance from the mass body 140 is not easily affected, thereby preventing the detection accuracy of the detected portion (outer peripheral surface 140b) by the detection coil 130a from being lowered.

  As a second feature point, the extending width w1 of the inertial mass body 140 (outer peripheral surface 140b) in the extending direction of the shaft member 141 is configured to exceed the coil diameter (diameter) w2 of the detection coil 130a, and the inertial force. The entire detection coil 130a is arranged within the extending width w1 of the mass body 140 (outer peripheral surface 140b). According to such a configuration, even if rattling of the inertial mass body 140 in the direction along the extending direction of the shaft member 141 occurs, the outer peripheral surface 140b of the inertial mass body 140 is out of the detection region of the detection coil 130a. Therefore, it is effective to secure a desired detection accuracy of the detected portion (outer peripheral surface 140b) of the inertial mass body 140 by the detection coil 130a. In the present invention, it is sufficient to have at least the first feature point described above, and the object of the present invention can be achieved even if the second feature point is not included if necessary. Is possible.

  Regarding the operation of the passenger restraint system 100 configured as described above, FIGS. 7 to 9 are referred to. FIG. 7 schematically shows a cross-sectional structure of the passenger restraint system 100 according to the present embodiment before the vehicle door 10 collides with the colliding object 200 side-by-side, and FIG. 8 shows the vehicle in FIG. A cross-sectional structure at the time of a side collision with the collision object 200 of the door 10 is schematically shown. Further, FIG. 9 schematically shows a state at the time of operation of the side collision sensor 130 of the present embodiment.

  Now, the vehicle collides with the colliding object 200 and comes into contact with the side surface of the vehicle door, and the door outer panel 11 of the vehicle door 10 shown in FIG. 7 receives an impact from the side (upper side in FIG. 7). Let us consider a case where the vehicle is displaced inward (downward in FIG. 7), which is the direction of. This collision mode is typically referred to as a so-called “pole collision” in which the vehicle collides with a collision object 200 such as a utility pole.

  The door outer panel 11 shown in FIG. 7 starts to be crushed when the collision object 200 enters due to a side collision with the collision object 200, and is displaced from a two-dot chain line position as shown in FIG. 8, for example, to a solid line position. The door beam 20 pressed through the door outer panel 11 along with this displacement bends inward of the vehicle. When the side collision sensor 130 is displaced inward of the vehicle together with the door beam 20 in accordance with the bending operation of the door beam 20, or when an impact on the door outer panel 11 is applied to the side collision sensor 130, the side collision sensor 130. Is activated, and the detection information S20 in FIG. 1 is detected. On the other hand, the acceleration sensor 110 detects information (acceleration information S10 in FIG. 1) regarding acceleration in the Y-axis direction (the direction of arrow 34 in FIGS. 5 and 6) acting on the vehicle at the time of a side collision with the colliding object 200. .

  Regarding the operation of the side collision sensor 130, as shown in FIG. 9, the inertial mass body 140 (indicated by a two-dot chain line in the drawing) at the initial position P <b> 1 is applied by the acceleration in the direction of arrow 34 acting on the side collision sensor 130. ), A load in the direction opposite to the acceleration, that is, a load in the direction of the arrow 36 acts. At this time, when acceleration exceeding the specified value overcomes the elastic biasing force of the coil spring 143 described above and acts on the side collision sensor 130, the inertial mass body 140 is rotated from the initial position P1 with the shaft member 141 as the rotation center by the inertial force. For example, it rotates to the first operating position P2 indicated by the solid line in the drawing, and further to the second operating position P3. The first operating position P2 is a position where the inertial mass body 140 rotates from the initial position P1 so as to approach the detection coil 130a at an angle θ1 in the direction of the arrow 30. The second operating position P3 is a position where the inertial mass body 140 is rotated from the initial position P1 so as to approach the detection coil 130a in the direction of the arrow 30 at an angle θ2.

  During the rotating operation of the inertial mass body 140, a distance between the detection coil 130a and the outer peripheral surface 140b of the inertial mass body 140 disposed to face the detection coil 130a, for example, within a predetermined time of the inertial mass body 140 or a predetermined time Regarding the rotation operation within the rotation section, the average distance between the detection coil 130 and the outer peripheral surface 140b of the inertial mass body 140 gradually decreases. For example, the linear distance between the portion of the outer peripheral surface 140b of the inertial mass 140 that is closest to the detection coil 130a and the detection coil 130a is d1 in the inertial mass 140 at the initial position P1, and the inertia at the first operating position P2. In the mass body 140, d2 (<d1), and in the inertial mass body 140 in the second operating position P3, d3 (<d2). Due to this distance change during the rotation of the inertial mass body 140, an impedance change occurs in the detection coil 130a. Accordingly, by associating the impedance information of the detection coil 130a with the rotation angle of the inertial mass body 140 in advance, the rotation angle and rotation angular velocity of the inertial mass body 140 can be detected based on the detection information of the detection coil 130a. It becomes. The above-mentioned “average distance between the detection coil 130 and the outer peripheral surface 140b of the inertial mass body 140” typically has an area of the coil surface of the detection coil 130a as S, and the coil surface of the detection coil 130a is inertial mass. When the volume projected on the outer peripheral surface 140b of the body 140 is V, it can be defined as a value obtained by dividing the volume V by the area S, that is, V / S.

  Note that it is preferable to typically employ an impedance change rate as the impedance information of the detection coil 130a. In this case, the relationship between the impedance change rate of the detection coil 130a and the rotation angle of the inertial mass body 140 is stored in a database in advance, and the rotation of the inertial mass body 140 is performed based on the impedance change rate actually detected by the detection coil 130a. An angle can be calculated. In order to derive the rotation angle of the inertial mass body 140 by simpler logic, the relationship between the impedance change rate of the detection coil 130a and the rotation angle of the inertial mass body 140 is particularly a linear relationship (linear relationship). preferable.

  Therefore, as a result of intensive studies on the relationship, the present inventors have devised the shape of the outer peripheral surface 140b of the inertial mass body 140, thereby reducing the impedance change rate of the detection coil 130a and the rotation angle of the inertial mass body 140. It has been found that it is possible to obtain a linear relationship or a relationship that allows linear approximation. For example, in the first rotation period (also referred to as “initial rotation”) of the inertial mass body 140, the change in the average distance from the detection coil 130a becomes large, and in the second rotation period of the inertial mass body 140, A method for characterizing the shape of the outer peripheral surface 140b of the inertial mass body 140 is effective so that the change in the average distance between them is small. For the feature of the shape of the inertial mass 140 in this case, reference is made to FIG.

  As shown in FIG. 10, the outer peripheral surface 140 b of the inertial mass body 140 includes a first region 144 and a second region 145. The first region 144 is a portion of the outer peripheral surface 140b that faces the detection coil 130a before the inertial mass body 140 rotates. When this first region 144 is compared with an arc C having a predetermined radius R centered on the shaft member 141, for example, indicated by a two-dot chain line in FIG. 10, the first region 144 is separated from the shaft member 141. It can be defined as a region where the rate of change in the rotation direction of the distance is relatively large. On the other hand, the second region 145 is a portion of the outer peripheral surface 140b that faces the detection coil 130a in the later stage of rotation of the inertial mass body 140. The second region 145 can be defined as a region where the rate of change in the rotation direction of the distance from the shaft member 141 is smaller than that of the first region 144. Therefore, the change in the average distance between the detection coil 130 and the outer peripheral surface 140 b is larger in the first region 144 than in the second region 145. As a result, a linear relationship or a relationship capable of linear approximation is obtained between the impedance change rate of the detection coil 130a and the rotation angle of the inertial mass body 140. Note that the shape of the first region 144 and the second region 145 is not limited to the shape shown in FIG. 10 as long as the shape satisfies such a relationship, and various changes can be made as necessary. is there. For example, although not particularly illustrated, the shapes of the first region 144 and the second region 145 can be determined by a structure in which a concave portion such as a groove or a hole is provided on the outer peripheral surface 140b of the inertial mass body 140 itself.

  As detection information detected by the detection coil 130 a of the side collision sensor 130, the rotation angle of the inertial mass body 140 is output from the ASIC 130 b to the CPU 152 of the ECU 150 as rotation operation information of the inertial mass body 140. Accordingly, the ASIC 130b referred to here constitutes an “output unit” in the present invention. Then, the CPU 152 calculates the rotational angular velocity of the inertial mass body 140 and the movement amount and movement speed of the door beam 20 that moves integrally with the inertial mass body 140. In addition to the rotation angle, a rotation angular velocity, a rotation angular acceleration, a rotation amount, or the like can be used as the rotation operation information of the inertial mass body 140 output from the ASIC 130b.

  In addition, the CPU 152 determines whether or not the calculated movement amount and movement speed of the door beam 20 are in the “on region relating to the side collision sensor 130”. Here, the “on-region related to the side collision sensor 130” is defined as an area where it is determined that a side collision of a predetermined mode has occurred based on the detection result of the side collision sensor 130. Typically, regarding the correlation between the moving speed and the moving distance of the door beam 20, an area where both the moving speed and the moving distance satisfy the specified conditions is defined as an ON area related to the side collision sensor 130, and an area other than the above areas is defined. Can be defined as the off region for the side collision sensor 130.

  The on-region for the side collision sensor 130 is based on the correlation between the moving speed and the moving distance of the door beam 20, and an object having a force sufficient to deform the door beam 20 collides with the side, so that the door beam 20 is actually apparent. When the vehicle door 10 is crushed due to deformation, the collision speed of the object that deforms the vehicle door 10 is equal to or higher than a certain value and the deformation is progressing, or a large and heavy object deforms the vehicle door 10 more than a predetermined amount. Further, it is assumed that the deformation is progressing at a predetermined speed or more. On the other hand, in the off region related to the side collision sensor 130, when the moving speed of the door beam 20 is relatively large and the moving distance of the door beam 20 is relatively small, for example, the vehicle door collides other than on the road or roadside object, for example, It is assumed that the car is collided with a shopping basket with a caster, a ball, a bat, etc. and is reversibly displaced. The off-region includes, for example, the correlation between the moving speed and the moving distance of the door beam 20 when a low-weight object collides sideways at a high speed, and the moving speed and the moving distance of the door beam 20 when a high-weight object collides sideways at a low speed. Correlation with is included.

  On the other hand, based on the acceleration information output from the acceleration sensor 110 (the above-described acceleration information S10), the CPU 152 determines whether or not the acceleration output value is in the “on region related to the acceleration sensor 110”. Here, the “on region relating to the acceleration sensor 110” is defined as a region where it is determined that the acceleration output value of the acceleration sensor 110 has reached a predetermined threshold value. A region other than the ON region, that is, a region where the acceleration output value of the acceleration sensor 110 is determined to be lower than a predetermined threshold value is defined as an “off region related to the acceleration sensor 110”.

  Then, the CPU 152 (ECU 150) finally has the movement amount and movement speed of the door beam 20 calculated based on the detection result of the side collision sensor 130 in the “on region relating to the side collision sensor 130”, and the acceleration of the acceleration sensor 110. When it is determined that the output value is in the “on region related to the acceleration sensor 110”, that is, when two conditions are satisfied, an operation signal is output to the airbag module 170. As a result, the airbag 174 is expanded and inflated in the occupant restraint region by the gas supply from the gas supply device 172 of the airbag module 170, and the airbag 174 that has been expanded and inflated becomes the side of the vehicle occupant (head, neck, shoulder Occupant restraint while relaxing the impact force acting on the body, chest, abdomen, knees, lower limbs, etc.). In this case, the acceleration sensor 110 functions as a safing sensor for the side collision sensor 130.

  As described above, according to the occupant restraint system 100 of the present embodiment, the side collision mode at the time of the side collision of the vehicle door 10 (vehicle) is appropriately set using the side collision sensor 130 with a simplified structure. It becomes possible to judge. That is, the side collision sensor 130 according to the present embodiment is configured mainly with the detection coil 130a and the inertial mass body 140, so that it is not necessary to use a complicated mechanism or an electronic component excessively. Further, the side collision sensor 130 is a non-contact type using the detection coil 130a, and has a characteristic such as being hardly affected by the surrounding environment because it is strong against shock and does not react to the shock. Since the detection coil 130a detects the inertial mass body 140 that rotates on the orbit of the rotation plane (rotation plane A1 in FIG. 5), it is effective to improve the detection accuracy of the rotation operation mode of the inertial mass body 140. The

  Moreover, in the present embodiment, as described above, the rotation plane A1 of the inertial mass body 140 and the coil extension plane A2 of the detection coil 130a intersect, and the extension width w1 of the inertial mass body 140 is equal to the detection coil 130a. By adopting an arrangement structure in which the entire detection coil 130a is disposed within the extending width w1 of the inertial mass body 140, the inertial mass body extends in the direction along the extending direction of the shaft member 141. Even when 140 rattles occur, the desired detection accuracy of the detection coil 130a can be ensured.

  Moreover, in the passenger | crew restraint system 100 of this Embodiment, it generate | occur | produced in order to determine the side collision mode of a vehicle based on both the information detected by the side collision sensor 130, and the information detected by the acceleration sensor 110. It is possible to properly determine whether the side collision is highly necessary to immediately restrain the vehicle occupant or is a minor or unnecessary necessity to immediately restrain the vehicle occupant. This is effective in further improving the accuracy of determination of the side collision mode.

  In the side collision sensor 130 of the above-described embodiment, a single sensor module in which the detection coil 130a and the inertial mass body 140 are integrally assembled with the base member 132 is attached to the door beam via the mounting bracket 21 together with the sensor module. Since it can be attached to 20, it becomes possible to construct a highly versatile side collision sensor for vehicle doors of different vehicle types.

  Further, since the door beam 20 extends over a wide range of the vehicle door 10 with respect to the longitudinal direction of the vehicle, by attaching a side collision sensor 130 to the door beam 20, a side collision can be stabilized over a wide range of the vehicle door 10. It becomes possible to detect. For example, not only the so-called pole collision in which the vehicle collides with the colliding object 200 such as the electric pole as described above, but also the collision mode referred to as a so-called “barrier collision” in which the host vehicle collides with a wall or another vehicle. Even in this case, stable side collision detection can be performed.

  Further, according to the above-described embodiment, the airbag module 170 is controlled using highly accurate information detected by the side collision sensor 130, thereby ensuring the restraint of the vehicle occupant.

  Further, if the occupant restraint system 100 of the above-described embodiment is used, a vehicle that uses highly accurate information detected by the side collision sensor 130 for control of various control objects related to the vehicle including the airbag module 170 is provided. The Rukoto.

(Other embodiments)
In addition, this invention is not limited only to said embodiment, A various application and deformation | transformation can be considered. For example, each of the following embodiments to which the above embodiment is applied can be implemented.

  In the above embodiment, both the information detected by the acceleration sensor 110 and the information detected by the side collision sensor 130 are used to control the airbag module 170 that operates to restrain the vehicle occupant during a vehicle side collision. In the present invention, the information detected by the acceleration sensor 110 and the information detected by the side collision sensor 130 are both used to control an occupant restraint device such as a seat belt device or to notify a vehicle side collision. It can also be used to control a notification device that performs display output and audio output to perform the above. In the present invention, the airbag module 170 and other control objects are controlled based on at least information detected by the side collision sensor 130, for example, only information detected by the side collision sensor 130. Can do.

  Further, in the side collision sensor 130 of the above-described embodiment, a coil that applies an elastic urging force to the inertial mass body 140 so that the inertial mass body 140 rotates when acceleration exceeding a specified acceleration acts on the sensor housing. Although the case where the spring 143 is used has been described, in the present invention, an elastic member other than the coil spring 143, for example, a leaf spring or the like may be employed. Further, instead of the elastic member such as the coil spring 143, a mechanism that prevents or allows the rotational operation of the inertial mass body 140 according to the acceleration acting on the side collision sensor 130 may be employed.

  In the above embodiment, the case where the inertia mass body 140 itself as a conductor or magnetic body is detected by the detection coil 130a has been described. However, in the present invention, the inertia mass body as a non-conductor or non-magnetic body is described. It is also possible to employ a configuration in which a detected portion of a conductor or a magnetic material is provided and the detected portion is detected by a detection coil.

  In the above embodiment, the configuration of the occupant restraint system to be mounted on the automobile has been described. However, the configuration of the occupant restraint system to be mounted on various vehicles such as an automobile, an aircraft, a ship, a train, a bus, and a truck. In contrast, the present invention can be applied.

DESCRIPTION OF SYMBOLS 10 ... Vehicle door 11 ... Door outer panel 12 ... Door inner panel 13 ... Partition area 14 ... Vehicle front side bracket 15 ... Vehicle rear side bracket 16 ... Door hinge 17 ... Vehicle main body 20 ... Door beam 21 ... Mounting bracket 100 ... Passenger restraint system 110 ... Acceleration sensor 130 ... Side collision sensor 130a ... Detection coil 130b ... ASIC
131 ... Bush 132 ... Base member 132a ... Side wall 132b ... Housing space 132c ... Mounting hole 133 ... Connector 134 ... Shield member 135 ... Sensor cover 136 ... Coil holder 140 ... Inertial mass 140a ... Through hole 140b ... Outer surface 141 ... Shaft Member 141a ... Groove 142 ... Clip 143 ... Coil spring 144 ... First region 145 ... Second region 150 ... ECU
152 ... CPU
170 ... Airbag module 172 ... Gas supply device 174 ... Airbag 200 ... Colliding object A1 ... Rotation plane A2 ... Coil extension plane P1 ... Initial position P2 ... First operation position P3 ... Second operation position

Claims (8)

A vehicle side collision sensor that operates by a side collision of a vehicle,
A sensor housing disposed in a partition area partitioned by a door outer panel and a door inner panel of the vehicle door;
A detection coil housed in the sensor housing so as to extend in the vehicle front-rear direction and supplied with an alternating current;
A rotating shaft housed in the sensor housing and extending in the vehicle longitudinal direction in parallel with the detection coil;
An inertial mass body that is allowed to rotate on a rotation plane that intersects with a coil extension surface of the detection coil around the rotation axis;
A conductive to-be-detected portion that is provided on the inertial mass body so as to face the detection coil, and the distance between the inertial mass body and the detection coil is variable in accordance with the rotation operation of the inertial mass body;
An output unit that outputs information on the rotational operation of the inertial mass body based on a change in impedance of the detection coil caused by a change in the distance between the detection coil and the detected portion during the rotational operation of the inertial mass body; ,
A vehicle side collision sensor characterized by comprising: The vehicle side collision sensor according to claim 1,
The detected portion is configured such that an extending width in the extending direction of the rotation shaft exceeds a coil diameter of the detecting coil, and the detecting coil is disposed within the extending width of the detected portion. A vehicle side collision sensor, characterized in that: The vehicle side collision sensor according to claim 1 or 2,
The vehicle side collision sensor, wherein the detected portion is configured by an outer peripheral surface of the inertia mass body. The vehicle side collision sensor according to any one of claims 1 to 3,
The vehicle is characterized in that the inertial mass body includes an elastic member that elastically biases the inertial mass body so as to rotate when an acceleration exceeding a preset acceleration is applied to the sensor housing. Side collision sensor. The vehicle side collision sensor according to any one of claims 1 to 4,
The sensor housing includes a single sensor module in which the inertia mass body and the detection sensor are integrally assembled and fixed to the sensor housing, and the sensor module is attached to the vehicle door side member via a mounting bracket. A vehicle side collision sensor characterized by having a configuration. A vehicle side collision detection system for detecting information on a side collision of a vehicle,
The vehicle side collision sensor according to any one of claims 1 to 5,
A determination unit for determining a side collision mode of the vehicle door;
With
The determination unit is configured to determine a side collision mode of the vehicle door based on information output from the output unit of the vehicle side collision sensor. The vehicle side collision detection system according to claim 6,
An occupant restraint device for restraining the vehicle occupant in the event of a side collision of the vehicle;
A control device that drives and controls the occupant restraint device based on information determined by the determination unit of the vehicle side collision detection system;
An occupant restraint system characterized by comprising: The occupant restraint system according to claim 7,
And an acceleration sensor for detecting information on acceleration acting on the vehicle.
The control device is configured to drive and control the occupant restraint device based on both information determined by the determination unit of the vehicle side collision detection system and information detected by the acceleration sensor. An occupant restraint system.

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