JP2006258647A - Vehicle collision detecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle collision detecting device saving labor and of low replacement cost, because, even if, for example, any corner section is wiped out, a long collision sensor is not necessary to replace entirely. <P>SOLUTION: The vehicle collision detecting sensor, capable of detecting vehicle collision to operate a safety apparatus, is characterized by including the long collision sensors 1 and 1' arranging pressure-sensitive sections along a longitudinal direction of a long and slender member, the signal processing means 2 and 2' processing the outputs from the long collision sensors 1 and 1' concerned, and the start-up controllers 3 and 3' starting up the aforementioned safety apparatus with signals from the signal processing means 2 and 2'concerned, while the long collision sensors 1 and 1' are arranged separately at a plurality parts of outer circumference of the vehicle. Since the long collision sensors are arranged separately at a plurality parts of outer circumference of the vehicle, only collision sensor losing its function due to wipe-out is needed to replace, resulting in saving labor and low replacement cost. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a safety device for protecting an occupant or a pedestrian from an impact when a vehicle such as an automobile collides, and more particularly, vehicle collision detection for instantaneously operating a safety device such as an air bag at the time of a collision. Relates to the device.

  Up to now, when a vehicle collides with an obstacle, collision detection for activating occupant protection safety devices such as airbags and seat belts installed in the vehicle, or pedestrian protection safety devices such as airbags installed in the hood Equipment has been developed.

  For example, as shown in FIG. 9, the conventional collision detection apparatus propagates through an optical fiber cable 74 stretched around the outer periphery of the vehicle body 72, a light emitting element portion 75 that transmits light to the optical fiber cable 74, and the optical fiber cable 74. The light conversion element unit 76 that receives the received light and converts it into an electric signal, a plurality of pressure sensing units 77 provided in the longitudinal direction of the optical fiber cable 74, and an electric signal from the light conversion element unit 76, such as an airbag. It is comprised from the collision detection circuit 78 which operates the safety device 73 (for example, refer patent document 1). As shown in FIG. 10, the pressure-sensitive portion 77 includes a cylindrical base portion 771 through which the optical fiber cable 74 is inserted, and a pair of projecting portions 772a and 772b protruding toward the direction in which an external pressure such as a collision is applied to the inner surface of the cylindrical base portion 771. One protrusion 774 is formed on the opposite surface of the intermediate part between the protrusions 772a and 772b. Therefore, when an external pressure such as a collision is applied, the cylindrical base is bent, and the protrusions 772a, 772b and the protrusion 774 bend the optical fiber cable 74 to reduce the amount of light transmitted.

  In general, when the automobile is moved, the corner of the vehicle body is frequently rubbed or bumped. As described above, the so-called long length comprising the optical fiber cable 74 and the pressure-sensitive portion 77 disposed along the longitudinal direction thereof. In the conventional collision detection device in which the collision sensor is stretched around the outer periphery of the vehicle body 72, it is necessary to replace the long collision sensor completely every time the corner portion is hit, which is troublesome and expensive. Had.

Further, when correcting the characteristic change due to the temperature of the collision sensor, there is a problem that the correction accuracy is low because the temperature of the outer periphery of the vehicle body is not uniform.
Japanese Patent Laid-Open No. 5-116592

  The present invention has been made in view of the above-described problems of the conventional collision detection device. For example, even if the corner portion is hit, it is not necessary to replace the long collision sensor completely, and the replacement cost is low. It is an object to provide an inexpensive vehicle collision detection device. It is another object of the present invention to provide a vehicle collision detection device that detects a collision with high accuracy by correcting a characteristic change due to a temperature of the collision sensor with high accuracy.

  The invention according to claim 1 to solve the problem is a vehicle collision detection device that activates a safety device by detecting a vehicle collision, and a pressure-sensitive portion is disposed along a longitudinal direction of an elongated member. A long collision sensor, a signal processing means for processing the output from the long collision sensor, and an activation controller that activates the safety device by a signal from the signal processing means. The collision sensor is divided into a plurality of parts on the outer periphery of the vehicle.

  Since the long collision sensor is divided into multiple parts on the outer periphery of the vehicle, it is only necessary to replace the collision sensor whose function has been lost by bumping, and it does not take time to replace it. Become cheap.

  The invention according to claim 2 is the vehicle collision detection device according to claim 1, further comprising temperature sensors disposed in the plurality of parts, wherein the activation controller is configured to output the temperature sensor. Based on this, the output of the collision sensor is corrected.

  Since the characteristic change due to the temperature of the collision sensor arranged in a plurality of parts is corrected by the temperature of the temperature sensor arranged in the same part, the collision can be detected with high correction accuracy and high accuracy. .

  The invention according to claim 3 is the vehicle collision detection device according to claim 1 or 2, wherein at least a part of the plurality of parts is two parts divided into two bumpers. .

  The bumper hits the corner frequently, but even if it hits the corner, it is only necessary to replace the collision sensor on the side of the bumper. This eliminates the need for replacement and reduces the replacement cost. Further, by installing the signal processing means in the center of the vehicle, it is possible to process the outputs of the two collision sensors with one signal processing means.

  The invention according to claim 4 is the vehicle collision detection device according to claim 1 or 2, wherein at least a part of the plurality of parts is three parts obtained by dividing the bumper into three parts. .

  Due to the structure of the vehicle, there is a radiator near the vehicle center, so the central part of the bumper is almost equal to the outside air temperature, but there are tire houses on the left and right sides of the bumper, so the outside air does not flow so much and the engine heat is accumulated. The temperature rises. By separately installing the collision sensor and the temperature sensor at the central part and the left and right side parts of the bumper, the temperature can be corrected for each part, and the collision can be detected with high accuracy.

  Since the long collision sensor is divided into multiple parts on the outer periphery of the vehicle, it is only necessary to replace the collision sensor whose function has been lost by bumping, and it does not take time to replace it. Become cheap. In addition, since the characteristic change due to the temperature of the collision sensor arranged in multiple parts is corrected by the temperature of the temperature sensor arranged in the same plural parts, the correction accuracy is high and the collision can be detected with high precision. Can do.

(Embodiment 1)
A vehicle collision detection device according to a first embodiment of the present invention will be described with reference to the drawings. 1 is a schematic configuration diagram of a vehicle collision detection device for detecting a frontal collision of an automobile according to Embodiment 1, FIG. 2 is a longitudinal sectional view of a collision sensor 1 in FIG. 1, and FIG. 3 is a diagram of a signal processing unit 2 in FIG. FIG. 4 is a cut perspective view of a pressure-sensitive cable switch which is another embodiment of the collision sensor 1.

  In FIG. 1, 5a and 5b are left and right front members constituting a vehicle body frame, 6 is a front bumper composed of a bumper force 61 and a bumper absorber 62 fixed to the front members 5a and 5b, 7a and 7b are left and right front wheels, CL is the center line of the vehicle body.

  1 is a collision sensor installed inside a bumper 6, for example, between a bumper force 61 and a bumper absorber 62 as shown in FIG. 1, and includes a collision sensor 1a extending to the right from the vehicle body center and a collision sensor 1b extending to the left. . That is, the long collision sensor 1 is divided into two on the left and right sides of the vehicle body center line CL. Reference numeral 2 denotes signal processing means disposed in the vicinity of the center line CL, and 3 denotes an activation controller for activating the safety device.

  The collision sensors 1a and 1b of this embodiment are sensors using optical fibers as shown in FIG. 2, for example, and the tips of protrusions formed at a predetermined distance from the optical fibers 11a and 11b are optical fibers. Bending members 12a and 12b arranged so as to come into contact with 11a and 11b are molded with molding members 13a and 13b. 112a and 112b are mirrors formed at the other end of the optical fibers 11a and 11b that reflect the light incident from the one end 111a and 111b.

  The optical fibers 11a and 11b have a high refractive index core and a low refractive index cladding, and are made of glass, plastic, silicone rubber, or the like, and an optical fiber made of silicone rubber is preferable. Even if it collides and deforms, the probability that it can be restored and reused increases. The bending members 12a and 12b are made of plastic or metal. The mirrors 112a and 112b may be coated with Al or Au on the end faces of the optical fibers 11a and 11b, or a bulk mirror may be attached. Plastic or rubber is used for the mold members 13a and 13b, but rubber is preferable. Even if it collides and deforms, the probability that it can be restored and reused increases.

  As shown in FIG. 2A, the optical fibers 11a and 11b of the collision sensors 1a and 1b before the collision are not bent, and the light incident from one end 111a or 111b is reflected by the mirrors 112a and 112b without being attenuated halfway. The light of almost the same intensity as the incident light is returned. On the other hand, as shown in FIG. 2B, when a collision is applied and a load is applied from the direction of the arrow, the optical fibers 11a and 11b are bent in contact with the protruding portions of the bending members 12a and 12b, and light propagating therethrough leaks. Since the intensity of the returning light decreases, a collision can be detected from the intensity of the returning light. Therefore, the mold members 13a and 13b correspond to elongated members, and the optical fibers 11a and 11b and the bending members 12a and 12b constitute a pressure-sensitive portion disposed along the longitudinal direction of the elongated members. Note that the collision sensor of this embodiment has an advantage of high collision detection sensitivity because light reciprocates in the optical fiber.

  The signal processing means 2 includes light sources 21a and 21b that allow light to enter the optical fibers 11a and 11b, photoelectric conversion elements 22a and 22b that convert light emitted from the optical fibers 11a and 11b into electrical signals, and photoelectric conversion elements 22a and 22b. An A / D converter 24 for converting an analog signal into a digital signal is provided. As the light sources 21a and 21b, LEDs, LDs, light bulbs, and the like can be used, and as the photoelectric conversion elements 22a and 22b, photodiodes, phototransistors, and the like can be used.

  Although not shown, the activation controller 3 holds a predetermined threshold value by a logical operation means such as an electronic circuit or a CPU, and compares the threshold value with the input collision sensor signal.

  The operation of the collision detection apparatus configured as described above is as follows. Light generated from the light sources 21a and 21b is reflected by the beam splitters 23a and 23b and is incident from one end 111a and 111b of the optical fibers 11a and 11b. The incident light propagates through the optical fibers 11a and 11b, is reflected by the mirrors 112a and 112b at the other end, and is returned to the signal processing means 2. The light returned to the signal processing means 2 passes through the beam splitters 23a and 23b, enters the photoelectric conversion elements 22a and 22b, and is converted into an electric signal. The electrical signals output from the photoelectric conversion elements 22a and 22b are input to the A / D converter 24, converted into digital signals, and input to the activation controller 3. The activation controller 3 compares the input digital signal with a predetermined threshold value. When the activation signal is equal to or less than the threshold value, the activation controller 3 determines that there is a collision and outputs an activation signal to a safety device (not shown).

  The vehicle collision detection device of the present embodiment includes a collision sensor 1a extending to the right from the vehicle body center and a collision sensor 1b extending to the left. Therefore, even if the collision sensor is damaged by hitting the left corner of the bumper, for example, the collision is detected. It is only necessary to replace the sensor 1b. Further, the signal processing of the two collision sensors 1a and 1b can be performed only by the signal processing means 2 disposed near the center line CL.

  As the collision sensors 1a and 1b, pressure-sensitive cable switches as shown in FIG. 4 may be used. The pressure-sensitive cable switch includes, for example, a pair of strip electrodes 41 and 42 on the same surface side of the inner periphery of the tube 44, and embeds conductive wires 45 and 46 in these strip electrodes, respectively, On the opposite surface, a strip electrode 43 is provided that contacts the strip electrodes 41 and 42 when the tube 44 is pressed and deformed, thereby conducting electrical connection therebetween.

  When the pressure-sensitive cable switch as described above is used for the collision sensors 1a and 1b, the signal processing means 2 naturally includes an electric circuit (not shown) that detects ON / OFF of the switch.

(Embodiment 2)
Embodiment 2 of a vehicle collision detection apparatus according to the present invention will be described with reference to the drawings. 5 is a schematic configuration diagram of a vehicle collision detection device that detects a frontal collision of an automobile according to the second embodiment, FIG. 6 is a longitudinal sectional view of a collision sensor 1 ′ in FIG. 5, and FIG. 7 is a signal processing unit 2 in FIG. FIG. 8 is a graph of output characteristics and temperature correction coefficient depending on the temperature of the collision sensor. In addition, the same code | symbol is attached | subjected to the same component as Embodiment 1, and description is abbreviate | omitted.

  In FIG. 5, 1 'is a collision sensor installed between the bumper force 61 and the bumper absorber 62 constituting the bumper 6, and is disposed in front of the radiator between the right front member 5a and the left front member 5b. The collision sensor 1'c, the collision sensor 1'a disposed outside the right front member 5a, and the collision sensor 1'b disposed outside the left front member 5b. That is, the long collision sensor 1 'is divided into three portions, that is, the front side of the radiator and the outer left and right portions of the front members 5a and 5b. Reference numeral 2 'denotes signal processing means disposed in the vicinity of the right front member 5a.

  The collision sensors 1′a, 1′b, 1′c of the present embodiment are basically similar to the collision sensor of the first embodiment, but as shown in FIG. 6, a mirror is provided at the other end. Instead of the arrangement, the output end fibers 112′a, 112′b and 112′c are provided. Light incident from the incident ends 111′a, 111′b, and 111′c propagates through the optical fibers 11′a, 11′b, and 11′c, respectively, and the outgoing end fibers 112′a, 112′b, and 112 ′. Although emitted from c, the intensity of the emitted light decreases because the optical fibers 11′a, 11′b, and 11′c are bent when a load due to collision is applied. Therefore, the collision can be detected from the intensity of the emitted light.

  Reference numerals 4a, 4b, and 4c denote temperature sensors arranged in the vicinity of the collision sensors 1'a, 1'b, and 1'c, respectively. As the temperature sensors 4a, 4b, 4c, a thermistor, a resistance temperature detector, or the like can be used as appropriate.

  The signal processing means 2 ′ includes light sources 21 ′ a, 21 ′ b, 21 ′ c that cause light to enter the incident ends 111 ′ a, 111 ′ b, 111 ′ c, and emission end fibers 112 ′ a, 112 ′ b, 112 photoelectric conversion elements 22'a, 22'b, 22'c for converting light from 'c into electrical signals, photoelectric conversion elements 22'a, 22'b, 22'c and temperature sensors 4a, 4b, 4c An A / D converter 24 ′ for converting an analog signal into a digital signal is provided.

  If the temperature changes even if the load applied by the collision is constant, the way the optical fibers 11'a, 11'b, and 11'c are bent changes. That is, when the temperature is high, the bend is large, and when the temperature is low, the bend is small. Therefore, when the temperature is high, the attenuation of light is large, and the intensity of the emitted light is low. The intensity of light increases. The temperature of the collision sensors 1'a and 1'b in front of the tire house increases due to the accumulated heat, and the output decreases even with the same collision load. On the other hand, the collision sensor 1'c in front of the radiator is substantially equal to the outside air temperature, and the output is increased. Therefore, in order to set a threshold value for output and output a start signal to the safety device, it is necessary to perform correction so that the same output is obtained with the same collision load regardless of the temperature.

When the relationship between the output VT of the collision sensor and the temperature T is examined, for example, output characteristics as indicated by a solid line in FIG. 8 are obtained. That is, when V80 = 0.84 at 80 ° C., V20 = 1.0 at 20 ° C., and V-40 = 1.25 at −40 ° C., the output is constant V′T regardless of the temperature. The temperature correction coefficient αT for
V'T = αT × VT (1)
From the relationship of FIG.

  The start controller 3 ′ holds data of the temperature correction coefficient αT, performs the calculation of the equation (1) based on the temperature detected by the temperature sensors 4a, 4b, 4c, and corrects the collision sensor output V ′ corrected. Find T. Then, V'T is compared with a predetermined threshold value, and if it is equal to or less than the threshold value, it is determined as a collision and an activation signal is output to a safety device (not shown).

  As described above, the vehicle collision detection device according to the present embodiment includes the collision sensors 1′a, 1′b, and 1 ′ that are divided and disposed at the three locations of the front side of the radiator and the outer left and right portions of the front members 5a and 5b. Since the output of c is corrected by the temperature of the temperature sensors 4a, 4b, and 4c arranged at the same site, the collision can be detected with high accuracy without being affected by the temperature.

It is a schematic block diagram of the vehicle collision detection apparatus which concerns on Embodiment 1 of this invention. It is sectional drawing of the collision sensor 1 in FIG. It is a block diagram of the signal processing means 2 in FIG. FIG. 6 is a cut perspective view of a pressure-sensitive cable switch which is another embodiment of the collision sensor 1 of FIG. 1. It is a schematic block diagram of the vehicle collision detection apparatus which concerns on Embodiment 2 of this invention. It is sectional drawing of the collision sensor 1 'in FIG. It is a block diagram of the signal processing means 2 'in FIG. It is a graph of the output characteristic by the temperature of a collision sensor, and a temperature correction coefficient. It is a schematic block diagram of the conventional vehicle collision detection apparatus. It is sectional drawing of a collision sensor.

Explanation of symbols

1, 1 ″ ······ Long collision sensor 2, 2 '···· Signal processing means 3, 3' ···· Starting controllers 4a, 4b, 4c ... Temperature sensor

Claims (4)

A vehicle collision detection device that activates a safety device by detecting a vehicle collision,
A long collision sensor having a pressure-sensitive portion disposed along the longitudinal direction of the elongated member;
Signal processing means for processing the output from the long collision sensor;
An activation controller that activates the safety device according to a signal from the signal processing means;
And the long collision sensor is divided into a plurality of parts on the outer periphery of the vehicle.   2. The vehicle collision detection according to claim 1, further comprising temperature sensors disposed at the plurality of parts, wherein the activation controller corrects an output of the collision sensor based on an output of the temperature sensor. apparatus.   The vehicle collision detection device according to claim 1, wherein at least a part of the plurality of parts is two parts obtained by dividing the bumper into two parts.   The vehicle collision detection device according to claim 1, wherein at least a part of the plurality of parts is three parts obtained by dividing a bumper into three parts.

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