JP4728727B2 - Shock detection optical fiber sensor, load transmission plate and manufacturing method thereof - Google Patents

Description

  The present invention relates to an impact detection optical fiber sensor, a load transmission plate, and a method for manufacturing the same, in which the material and shape of a load transmission plate for bending (deforming) a plastic optical fiber are devised.

  The impact detection optical fiber sensor is provided in a vehicle such as an automobile, for example, and detects (recognizes) an impact (collision or load) caused by a measurement object such as another vehicle or an obstacle from a light amount loss due to the bending of the optical fiber. It is also used as a collision recognition sensor or a load recognition sensor.

  This optical fiber sensor is provided with a load transmission plate (stress concentration plate) for bending the optical fiber by a load such as an impact. The load transmission plate transmits and concentrates stress due to a load, such as an impact applied to the optical fiber sensor, to the optical fiber to make it easier to bend the optical fiber.

  A conventional impact detection optical fiber sensor 110 as shown in FIGS. 11 (a) and 11 (b) includes a metal load transmission plate 111 and a resin optical fiber (hereinafter referred to as HPOF (heat resistant plastic)). 112) (referred to as an optical fiber) is a sensor shape embedded in a mold member 113 made of soft rubber.

  In the sensor 110, for example, when a load generated by the collision is applied, the HPOF 112 is bent and deformed at the punched portion (hole) 114 of the load transmission plate 111, so the collision is detected from a light amount loss due to the bending deformation.

  The prior art document information related to the invention of this application includes the following.

JP-T-2002-531812

  However, the elastic modulus of the soft rubber changes with temperature as shown in FIG. 12 (temperature dispersion is large). Therefore, when the HPOF 112 is deformed through the soft rubber by an external load like the sensor 110, the deformation amount of the HPOF 112 varies depending on the deformation amount depending on the temperature of the soft rubber, and the light amount loss changes. Therefore, the sensitivity of the sensor 110 is easily changed depending on the temperature, and the temperature is unstable.

  Further, if a rubber having a temperature dispersion as small as possible is selected instead of the soft rubber, the sensor becomes expensive.

  Therefore, an object of the present invention is to provide an impact detection optical fiber sensor and a load transmission plate having a structure in which a plastic optical fiber is deformed only by deformation of a metal having a small temperature dispersion by using an external load without using rubber having a large temperature dispersion. And a manufacturing method thereof.

The present invention has been devised to achieve the above object, and the invention of claim 1 forms an elongated metal fiber support and a plurality of the metal fiber supports along the longitudinal direction. after forming the hole in which the bent into a tubular shape to form a load transfer plate in the longitudinal direction, seen write sandwiched plastic optical fiber in the load transmission plate, on the cylindrical metallic fiber support And an impact detection optical fiber sensor in which the plurality of holes are formed so that the positions thereof are shifted on one side and the opposite side of the cylindrical metal fiber support .

  The invention of claim 2 forms an elongated metal fiber support, forms a plurality of holes along the longitudinal direction in the metal fiber support, and then arranges the two in parallel, This is an impact detection optical fiber sensor in which a load transmission plate is formed by connecting with a spring member, and a plastic optical fiber is sandwiched between the load transmission plates.

  According to the invention of claim 3, after forming an elongated metal fiber support and forming a plurality of holes in the metal fiber support along the longitudinal direction, this is formed into a U-shape along the longitudinal direction. Alternatively, an impact detection optical fiber sensor in which a load transmission plate is formed by bending in a U-shape and a plastic optical fiber is sandwiched between the load transmission plates.

  A fourth aspect of the present invention is the impact detection optical fiber sensor according to the third aspect, wherein a reinforcing metal rod is inserted into the bent portion of the metal fiber support.

  The invention according to claim 5 is the impact detecting optical fiber sensor according to claim 3 or 4, wherein a deformation amount control projection for limiting a deformation amount of the open portion is provided on an inner surface of the open portion of the metal fiber support. is there.

  The invention of claim 6 is the impact detection optical fiber sensor according to any one of claims 3 to 5, wherein a positioning projection for positioning the plastic optical fiber is provided on the inner surface of the metal fiber support.

  The invention according to claim 7 is the impact detection optical fiber sensor according to claim 3 or 4, wherein one end of the open portion of the metal fiber support is bent in a U shape so as to contact the inner surface of the opposite end.

  The invention according to claim 8 is the impact detection optical fiber sensor according to claim 7, wherein a bulge portion is formed by bending the opposite side of the metal fiber support into a concavo-convex shape to prevent displacement of the plastic optical fiber.

  The invention according to claim 9 is the impact detection optical fiber sensor according to claim 3, wherein the plurality of holes are formed in a bent portion of the metal fiber support.

  According to a tenth aspect of the present invention, the plurality of holes are formed on the opposite side to the one side of the metallic fiber support so that the positions of the holes are shifted on one side and the opposite side of the metallic fiber support. The impact detection optical fiber sensor according to any one of 3 to 9.

  According to an eleventh aspect of the present invention, the plurality of holes are formed in the two metal fiber supports so that the positions of the one metal fiber support and the other metal fiber support are shifted. Item 3. The impact detection optical fiber sensor according to Item 2.

  A twelfth aspect of the present invention is the impact detection optical fiber sensor according to any one of the first to eleventh aspects, wherein at least a part of the plurality of holes is formed in an elliptical shape.

The invention of claim 13 forms an elongated metal fiber support, and after forming a plurality of holes in the metal fiber support along the longitudinal direction, this is formed into a cylindrical shape along the longitudinal direction. A load transmission plate formed by bending and forming the plurality of holes in the cylindrical metal fiber support so that the positions of the holes are shifted on one side and the opposite side of the cylindrical metal fiber support. is there.

  The invention of claim 14 forms an elongated metal fiber support, and after forming a plurality of holes along the longitudinal direction in the metal fiber support, the two are arranged in parallel, It is a load transmission plate formed by connecting with a spring member.

  The invention according to claim 15 forms an elongated metal fiber support, and after forming a plurality of holes in the metal fiber support along the longitudinal direction, this is formed into a U-shape along the longitudinal direction. Alternatively, it is a load transmission plate formed by bending in a U-shape.

According to the invention of claim 16, a long and narrow metal fiber support is formed by pressing, and a plurality of holes are formed in the metal fiber support along the longitudinal direction, and then the metal fiber support is formed along the longitudinal direction. bent in a tubular shape to form a load transmission plate Te, see write sandwiched plastic optical fiber in the load transmission plate, on the cylindrical metallic fiber support, the tubular made of metal the plurality of holes It is a manufacturing method of the impact detection optical fiber sensor formed so that a position may shift in one side and the opposite side of a fiber support, respectively .

  In the invention of claim 17, a long and thin metal fiber support is formed by press working, and a plurality of holes are formed in the metal fiber support along the longitudinal direction. This is a manufacturing method of an impact detection optical fiber sensor in which a load transmission plate is formed by connecting with a spring member and a plastic optical fiber is sandwiched between the load transmission plates.

  According to the invention of claim 18, an elongated metal fiber support is formed by pressing, and a plurality of holes are formed in the metal fiber support along the longitudinal direction. This is a method of manufacturing an impact detection optical fiber sensor in which a load transmission plate is formed by bending it into a U shape or a U shape, and a plastic optical fiber is sandwiched between the load transmission plates.

  According to the present invention, it is possible to obtain an impact detection optical fiber sensor that is inexpensive and stable in temperature.

  Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1A is a cross-sectional view of an impact detection optical fiber sensor showing a preferred first embodiment of the present invention, FIG. 1B is a cross-sectional view taken along the line 1B-1B, and FIG. It is the 1C-1C line section arrow directional view.

  As shown in FIGS. 1 (a) to 1 (c), an impact detection optical fiber sensor 10 according to the first embodiment forms an elongated metal fiber support 2 by pressing, and the metal A plurality of rectangular holes 3 are punched and formed in the fiber support 2 at predetermined intervals along the longitudinal direction, and then bent into an elliptical cylindrical shape along the longitudinal direction to transmit the load. A plate 1 is formed, and a plastic optical fiber (POF) 4 is sandwiched (wrapped) in the load transmission plate 1.

  The direction in which a load such as an impact is applied to the sensor 10 is the left-right direction in FIG. 1A, the direction perpendicular to the paper surface in FIG. 1B, and the up-down direction in FIG. Also, the right half of FIG. 1A is one side of the metal fiber support 2 and the left half of FIG. 1A is the opposite side of the metal fiber support 2. These also apply to FIGS. 2 to 8 described later.

  More specifically, each of the plurality of holes 3 has a central portion opposite to one side of the metal fiber support 2 so that the positions (phases) thereof are shifted from one side to the opposite side of the metal fiber support 2. It is formed. Further, the POF 4 is sandwiched at the central portion along the longitudinal direction in the load transmitting plate 1. The POF 4 is in contact with each hole 3 formed on both sides of the metal fiber support 2.

  The material of the metal fiber support 2 may be anything as long as it is generally used as a spring material, and examples thereof include copper alloys such as phosphor bronze and beryllium copper, and iron alloys such as stainless steel. As POF4, HPOF may be used.

  What is necessary is just to change suitably the magnitude | size of each hole 3, the punching pitch of each hole 3, the thickness of the metal fiber support body 2, and a material by loads, such as an impact to detect.

  The operation of the first embodiment will be described.

  In the sensor 10, when the load is applied, due to a load such as an impact from the outside, as shown in FIG. 1 (c), for example, the x portion on one side of the metal fiber support 2 (the portion between the adjacent holes 3) is deformed. Then, the POF 4 in contact with the x portion falls into the hole 3 in the y portion on the opposite side of the metal fiber support 2 and deforms. As a result, the light amount loss of the POF 4 changes, and the sensor 10 detects an impact caused by the measurement object. At the time of unloading at which the load such as impact disappears, the deformation of the x part on one side of the metal fiber support 2 is restored and the deformation of the POF 4 is also restored.

  As described above, in the sensor 10, the load transmitting plate 1 has a spring property (elasticity) in a direction in which a load is applied by forming the load transmitting plate 1 by bending the metal fiber support 2 into an elliptic cylinder. That is, the sensor 10 has a structure in which the POF 4 is deformed only by the deformation of the metal fiber support 2 having a small temperature dispersion by a load such as an impact from the outside without using rubber having a large temperature dispersion as in the prior art.

  Therefore, the sensor sensitivity of the sensor 10 is hardly changed depending on the temperature, and is stable to the temperature.

  Further, the sensor 10 is inexpensive because it does not require the mold member 113 of FIG. 11, has a small number of parts, and does not need to select expensive rubber having a small temperature dispersion as the material of the mold member 113.

  Furthermore, since the load concentration plate 1 can be easily and quickly manufactured using press working, the sensor 10 can be assembled in a short time, and the productivity of the sensor 10 is improved.

  In the sensor 10, the plurality of holes 3 are formed so that the positions thereof are shifted on one side and the opposite side of the metal fiber support 2, so that the sensor sensitivity can be improved as compared with the case where the positions are matched. .

  A second embodiment will be described.

  As shown in FIGS. 2A to 2C, the shock detection optical fiber sensor 20 according to the second embodiment forms two elongated metal fiber supports 2a and 2b by press working. In addition, a plurality of rectangular holes 23 are formed at predetermined intervals along the longitudinal direction at the center of each metal fiber support 2a, 2b, and one metal fiber support 2a and the other metal fiber. After punching out the position (phase) with the support 2b and forming each, the two metal fiber supports 2a and 2b are arranged in parallel, and both sides are connected by spring members 24, respectively. The load transmission plate 21 is formed, and the POF 4 is sandwiched between the center portions along the longitudinal direction of the load transmission plate 21. The POF 4 is in contact with each hole 23 formed in each metal fiber support 2a, 2b.

  As the spring member 24, a plate spring made of the same material as the metal fiber supports 2a and 2b may be used.

  In the sensor 20, the metal fiber supports 2a and 2b arranged in parallel with each other are connected by the spring member 24 to form the load transmission plate 21, so that the load transmission plate 21 has a spring property in the direction in which the load is applied. . This sensor 20 also provides the same operational effects as the sensor 10 of FIG.

  Further, a substantially square cylindrical load transmission plate may be formed by bending a single metal fiber support so as to have the same shape as the load transmission plate 21.

  A third embodiment will be described.

  As shown in FIG. 3A to FIG. 3C, the impact detection optical fiber sensor 30 according to the third embodiment forms an elongated metal fiber support 2 by pressing, and the metal A plurality of rectangular holes 3 are arranged at predetermined intervals along the longitudinal direction at a central portion on the opposite side to one side of the fiber support 2 (phases opposite to one side and the opposite side of the metal fiber support 2). ) Are formed so as to be displaced from each other and then bent into a U-shape along the longitudinal direction to form the load transmission plate 31, and the POF 4 is sandwiched between the central portions along the longitudinal direction of the load transmission plate 31. It was produced by. The POF 4 is in contact with each hole 3 formed on both sides of the metal fiber support 2.

  In the sensor 30, the load transmitting plate 31 has a spring property in a direction in which a load is applied by bending the metal fiber support 2 into a U shape to form the load transmitting plate 31. This sensor 30 also provides the same operational effects as the sensor 10 of FIG.

  Next, modified examples related to the sensor 30 will be described with reference to FIGS.

  As shown in FIGS. 4A to 4C, the impact detection optical fiber sensor 40 is obtained by inserting a reinforcing metal rod 43 into the bent portion 42 of the metal fiber support 2. In the sensor 40, the metal rod 43 can prevent buckling of the bent portion 42, which is a portion that bears the spring property.

  As shown in FIGS. 5A to 5C, the impact detection optical fiber sensor 50 is formed on the inner surface of the open portion 52 of the metal fiber support 2 in addition to the configuration of the sensor 40 of FIG. The load transmission plate 51 is provided with a deformation amount control projection 53 for controlling the deformation amount of the opening 52, and a positioning projection 54 for positioning the POF 4 at the center of the inner surface of the metal fiber support 2. It was. In the sensor 50, the deformation amount of the opening portion 52 is limited by the deformation amount control projection 53, so that excessive deformation of the opening portion 52 can be prevented. Further, the positioning projection 54 facilitates positioning of the POF 4.

  As shown in FIGS. 6A to 6C, the impact detection optical fiber sensor 60 includes one end of the open portion of the metal fiber support 2 (see FIG. 4A) in addition to the configuration of the sensor 40 in FIG. 6, a load transmission plate 61 having a bent portion 65 bent in a U-shape so as to contact the inner surface of the other end (the left end in FIG. 6) is used. In the sensor 60, by using the load transmission plate 61, the open portion of the metal fiber support 2 also has a spring property. The tip of the bent portion 65 and the other end of the open portion of the metal fiber support 2 are preferably in close contact with each other, but may be separated if they are minute.

  As shown in FIGS. 7A to 7C, the impact detection optical fiber sensor 70 has a central portion on the opposite side of the metal fiber support 2 in addition to the configuration of the sensor 60 in FIG. A load transmission plate 71 is used which is formed with a raised portion 72 that is bent into an uneven shape and prevents the POF 4 from shifting. In the sensor 70, the swell portion 72 can prevent the POF 4 from being displaced, and the POF 4 can be easily positioned.

  As shown in FIGS. 8A to 8B, the impact detection optical fiber sensor 80 is a modification of the sensor 70 in FIG. 7A, and instead of the hole 3 on one side of the fiber support 2. A plurality of elliptical holes 82 are formed, and a load transmission plate 81 is used in which a rectangular hole 83 having substantially the same dimensions as the hole 82 is formed in place of the hole 3 on the opposite side of the fiber support 2. . In the sensor 80, the oval holes 82 can reduce damage when the POF 4 is deformed.

  However, also in each sensor of FIGS. 1-7, you may form at least one part of the some holes 3 and 23 in an ellipse. As a modified example of the sensor 30 in FIG. 3A, a modified example of the modified example of FIGS.

  As shown in FIGS. 9 (a) and 9 (b), the impact detection optical fiber sensor 90 is different from the sensor 30 of FIG. 3 (a) in that the metal fiber support 2 is bent into a U shape. After punching and forming a plurality of rectangular holes 93 in the bent portion 92 of the metal fiber support 2 by pressing as in the case of the holes 3, the bent holes p and q in FIG. The load transmitting plate 91 is formed by bending it into a U-shape, and the load transmitting plate 91 is produced by sandwiching the POF 4 at the bent portion 92. The POF 4 is in contact with each hole 3 formed on both sides of the metal fiber support 2 and each hole 93 formed in the bent portion 92.

  In the sensor 90, the metal fiber support 2 is bent in a U shape to form the load transmission plate 91, so that the load transmission plate 91 has a spring property in the direction in which the load is applied (vertical direction in FIG. 9A). Have. Further, the sensor 90 has better workability than the sensor 30 because the load transmission plate 91 is U-shaped. Further, in the sensor 90, the deformation of the POF 4 is easier than that of the sensor 30 due to the holes 93 formed in the bent portion 92.

  Further, instead of the load transmission plate 91, as shown in FIG. 10, a plurality of elliptical holes 82 are formed on one side of the fiber support 2 instead of the holes 3, and holes are formed on the opposite side of the fiber support 2. Instead of 3, a load transmission plate formed by forming a rectangular hole 83 having substantially the same size as the hole 82 and then bending the hole 83 in a U-shape along the folding lines r and s may be used. This load transmission plate was formed so that the positions of the holes 82, 83, and 93 were all shifted.

FIG. 1A is a cross-sectional view of an impact detection optical fiber sensor showing a preferred first embodiment of the present invention, FIG. 1B is a cross-sectional view taken along the line 1B-1B, and FIG. It is the 1C-1C line section arrow directional view. 2A is a transverse cross-sectional view of an impact detection optical fiber sensor showing a preferred second embodiment of the present invention, FIG. 2B is a cross-sectional view taken along line 2B-2B, and FIG. It is the 2C-2C line section arrow directional view. 3A is a transverse cross-sectional view of an impact detection optical fiber sensor showing a preferred third embodiment of the present invention, FIG. 3B is a cross-sectional view taken along line 3B-3B, and FIG. It is the 3C-3C sectional view taken on the line. 4A is a transverse sectional view showing a modification of the impact detection optical fiber sensor of FIG. 3A, FIG. 4B is a sectional view taken along the line 4B-4B, and FIG. FIG. 5A is a transverse sectional view showing a modification of the impact detection optical fiber sensor of FIG. 4A, FIG. 5B is a sectional view taken along the line 5B-5B, and FIG. FIG. 6A is a transverse sectional view showing a modification of the impact detection optical fiber sensor of FIG. 4A, FIG. 6B is a sectional view taken along the line 6B-6B, and FIG. It is a -6C line section arrow directional view. 7A is a transverse cross-sectional view showing a modification of the impact detection optical fiber sensor of FIG. 6A, FIG. 7B is a cross-sectional view taken along line 7B-7B, and FIG. 7C is 7C. It is a -7C line section arrow directional view. FIG. 8A is a transverse sectional view showing a modification of the impact detection optical fiber sensor of FIG. 7A, FIG. 8B is a sectional view taken along the line 8B-8B, and FIG. It is a -8C line section arrow directional view. FIG. 9A is a perspective view showing a modification of the impact detection optical fiber sensor of FIG. 3A, and FIG. 9B is a development view of a load transmission plate used therefor. It is an expanded view which shows an example of a load transmission board. 11A is a longitudinal sectional view (cross-sectional view taken along the line 11A-11A in FIG. 11B) of the impact detection optical fiber sensor of the background art, and FIG. 11B is a transverse sectional view thereof. It is a figure which shows the temperature dependence of the elasticity modulus of a soft rubber (silicone) material.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Load transmission board 2 Metal fiber support body 3 Hole 4 Plastic optical fiber 10 Impact detection optical fiber sensor

Claims (18)

In addition to forming an elongated metal fiber support, a plurality of holes are formed in the metal fiber support along the longitudinal direction, and then bent into a cylindrical shape along the longitudinal direction to form a load transmission plate and, only write to sandwich the plastic optical fiber in the load transfer plate,
An impact detection optical fiber, wherein the cylindrical metal fiber support is formed such that the plurality of holes are displaced from one side and the other side of the cylindrical metal fiber support. Sensor.   A long and narrow metal fiber support is formed, and a plurality of holes are formed in the metal fiber support along the longitudinal direction. An impact detection optical fiber sensor characterized in that a transmission plate is formed and a plastic optical fiber is sandwiched between the load transmission plates.   A long and narrow metal fiber support is formed, and a plurality of holes are formed in the metal fiber support along the longitudinal direction, and then bent into a U shape or a U shape along the longitudinal direction. An impact detection optical fiber sensor characterized in that a load transmission plate is formed and a plastic optical fiber is sandwiched between the load transmission plates.   4. The impact detection optical fiber sensor according to claim 3, wherein a reinforcing metal rod is inserted into a bent portion of the metal fiber support.   The impact detection optical fiber sensor according to claim 3 or 4, wherein a deformation amount control projection for limiting a deformation amount of the open portion is provided on an inner surface of the open portion of the metal fiber support.   6. The impact detection optical fiber sensor according to claim 3, wherein a positioning projection for positioning the plastic optical fiber is provided on an inner surface of the metal fiber support.   The impact detection optical fiber sensor according to claim 3 or 4, wherein one end of the open portion of the metal fiber support is bent in a U shape so as to contact the inner surface of the opposite end.   8. The impact detection optical fiber sensor according to claim 7, wherein a raised portion for bending the plastic optical fiber is formed by bending the opposite side of the metal fiber support into an uneven shape.   4. The impact detection optical fiber sensor according to claim 3, wherein the plurality of holes are formed in a bent portion of the metal fiber support. On one side and the opposite side of the metallic fiber substrate, the plurality of holes of any one of claims 3-9 which were formed such that the position is shifted in the opposite side to one side of the metal fiber supports Shock detection optical fiber sensor.   3. The impact detection light according to claim 2, wherein the plurality of holes are formed in the two metal fiber supports so that the positions of the holes are shifted between one metal fiber support and the other metal fiber support. Fiber sensor.   The impact detection optical fiber sensor according to claim 1, wherein at least a part of the plurality of holes is formed in an elliptical shape. Along with forming an elongated metal fiber support, after forming a plurality of holes along the longitudinal direction in the metal fiber support, this is formed by bending it into a cylindrical shape along the longitudinal direction ,
A load transmission plate, wherein the cylindrical metal fiber support is formed such that the plurality of holes are displaced from one side and the other side of the cylindrical metal fiber support .   Form an elongated metal fiber support and form a plurality of holes in the metal fiber support along the longitudinal direction, then place them in parallel and connect them with a spring member A load transmission plate characterized by that.   A long and narrow metal fiber support is formed, and a plurality of holes are formed in the metal fiber support along the longitudinal direction, and then bent into a U shape or a U shape along the longitudinal direction. A load transmission plate characterized by being formed. A long and narrow metal fiber support is formed by pressing, and a plurality of holes are formed in the metal fiber support along the longitudinal direction. the transfer plate forms, seen write sandwiched plastic optical fiber in the load transmission plate,
An impact detection optical fiber, wherein the cylindrical metal fiber support is formed such that the plurality of holes are displaced from one side and the other side of the cylindrical metal fiber support. Sensor manufacturing method.   By forming a long and thin metal fiber support by pressing, a plurality of holes are formed in the metal fiber support along the longitudinal direction, and then two of them are arranged in parallel, and a spring member is used. A method of manufacturing an impact detection optical fiber sensor, comprising: connecting and forming a load transmission plate; and sandwiching a plastic optical fiber between the load transmission plates.   A long and narrow metal fiber support is formed by pressing, and a plurality of holes are formed in the metal fiber support along the longitudinal direction. A method for producing an impact detection optical fiber sensor, comprising: forming a load transmission plate by bending the shape into a shape, and sandwiching a plastic optical fiber between the load transmission plates.

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