JP2016031268A - Planar load sensor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a planar load sensor device that can detect a load working on any deformed face of a measurement object, which has a deformable face subject to deformation by a load, without requiring many sensor parts.SOLUTION: A planar load sensor device is provided with an optical fiber 2 in which a hetero core part 3 is arranged in the peripheral part or flank of the measurable area of a deformed face Sf of a measurement object W, and a linear or planar force transmitting member 5 so configured as to transmit a force that varies the degree of bending of the hetero core part 3 to the deformed face Sf according to the deformation of the deformed face Sf in the measurable area.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a planar load sensor device configured using an optical fiber.

  As a sensor device that detects a load acting on a surface area, for example, as disclosed in Patent Documents 1 and 2, a sensor device including a sensing portion in each of a plurality of local portions of a planar member is generally known.

JP 2008-32222 A JP 2009-276127 A

  In conventional sensor devices such as those disclosed in Patent Documents 1 and 2, since a large number of sensing parts are provided in a planar member, the sensor device tends to be complicated and expensive. Moreover, the calculation processing load of the measuring device that performs signal processing from a large number of sensing units tends to be large.

  The present invention has been made in view of such a background, and acts on a measurement object having a deformation surface deformed by a load, without requiring a large number of sensing parts, and acts on the deformation surface of the measurement object. An object of the present invention is to provide a planar load sensor device that can detect a load to be applied.

The planar load sensor device of the present invention is a planar load sensor device that detects a load acting on a deformation surface of a measurement object having a deformation surface that is deformed by a load in order to achieve the above-described object,
An optical transmission part having a core and a cladding, and a hetero core part having a core and a cladding respectively connected to the core and the cladding of the optical transmission part, wherein the core of the hetero core part is formed with a different diameter from the core of the optical transmission part And an optical fiber in which the hetero-core portion is disposed at a peripheral portion or a side of a measurement target region of the deformation surface of the measurement target;
A linear or planar force transmission member configured to transmit a force that changes the degree of bending of the hetero-core portion of the optical fiber to the optical fiber according to the deformation of the deformation surface in the measurement target region; (First invention).

  According to the first aspect of the present invention, when the deformation of the deformation surface in the measurement target region occurs due to the load acting on the measurement target region of the deformation surface of the measurement target, the force corresponding to the deformation is the peripheral portion of the measurement target region. Or it acts on the hetero core part of the said optical fiber arrange | positioned at a side through a linear or planar force transmission member. And the bending degree of a hetero core part changes with the force.

  Accordingly, the degree of bending of the hetero core portion changes according to the deformation caused by the load on the deformation surface in the measurement target region. In this case, the change in the degree of bending of the hetero core portion depends on the degree of load applied to the deformation surface in the measurement target region, the magnitude of the load, and the like.

  Here, in the optical fiber having the hetero core part, when light enters the core of the optical transmission part of the optical fiber, a part of the incident light leaks out at the hetero core part. The amount of light leakage increases as the degree of bending of the heterocore portion increases. For this reason, the greater the degree of bending of the heterocore portion, the greater the light transmission loss in the optical fiber.

  Therefore, by making light incident on the optical fiber and measuring the transmission loss of the light, it is possible to grasp the degree of bending of the hetero-core portion, and consequently the state of the load acting on the deformation surface of the measurement object in the measurement object region. It can be detected.

  Therefore, according to the planar load sensor device of the first invention, a measurement object having a deformation surface that is deformed by a load can be applied to the deformation surface of the measurement object without requiring a large number of sensing parts. The acting load can be detected.

  The first aspect of the present invention can employ the following aspects as a more specific configuration. That is, in the first aspect of the first invention, the force transmission member extends along the deformation surface in the measurement target region and is stretched so as to bend in accordance with the deformation of the deformation surface or The flexible linear member is constituted by a plurality of flexible linear members, and the flexible linear member is deformed by deformation of the flexible linear member accompanying deformation of the deformation surface in the measurement target region. The tension generated in the optical fiber is coupled to the optical fiber so as to be transmitted to the optical fiber as a force that changes the degree of bending of the hetero core portion (second invention).

  According to the second aspect of the present invention, a force corresponding to the deformation of the deformation surface in the measurement target region is transmitted to the optical fiber by the tension of the flexible linear member, and the bending degree of the hetero core portion of the optical fiber is transmitted. Can be changed.

  Therefore, the bending degree of the hetero core portion can be changed according to the state of the load acting on the deformation surface in the measurement target region.

  In the second invention, the force transmission member is constituted by a plurality of flexible linear members, and each of the plurality of flexible linear members has an end portion at an arrangement position of the hetero-core portion of the optical fiber. It is preferably arranged so as to be concentrated, connected to the hetero core portion, and arranged to extend radially from the one end side along the deformation surface in the measurement target region (third). invention).

  According to the third aspect of the invention, since the plurality of flexible linear members connected to the hetero-core portion of the optical fiber extend radially, even if the measurement target area is wide, the load acting on each part is not affected. Thus, the bending degree of the hetero core portion can be changed. Therefore, even if the measurement target region is large, it is possible to detect with high sensitivity loads acting on various parts of the measurement target region.

  The third invention further includes a connecting member fixed to the optical fiber at two portions of a portion near the one end in the axial direction of the heterocore portion and a portion near the other end. It is preferable that one end of each of the flexible linear members is fixed to the connecting member and connected to the hetero-core portion of the optical fiber via the connecting member (fourth invention).

  According to the fourth aspect of the invention, since the connecting member can employ various shapes, it is easy to connect a plurality of flexible linear members to the heterocore portion. In addition, it is possible to prevent the tension of the flexible linear member from acting only on a specific portion of the hetero core portion, thereby preventing the hetero core portion from being damaged.

  In the second to fourth inventions, the flexible linear member is further provided with an elastic sheet that is disposed so as to cover the deformation surface in the measurement target region and elastically deforms following the deformation of the deformation surface. Can adopt a configuration of being mounted on the elastic sheet (fifth invention).

  According to the fifth aspect of the invention, the flexible linear member can be mounted in advance on the elastic sheet, so that the planar load sensor device can be easily installed on the measurement object. .

  The first aspect may employ the following aspects. That is, in the second aspect of the first aspect of the invention, the force transmission member is arranged so as to cover the deformation surface in the measurement target region, and is configured by an elastic sheet that elastically deforms following the deformation of the deformation surface. The elastic sheet transmits the elastic force generated by the elastic deformation of the elastic sheet accompanying the deformation of the deformation surface in the measurement target region to the optical fiber as a force that changes the bending degree of the hetero core portion. For this purpose, a local portion of the peripheral portion of the elastic sheet is connected to the hetero-core portion of the optical fiber, and a portion of the peripheral portion of the elastic sheet that is spaced from the local portion is measured. It is fixed to the measurement object at the periphery of the target region (sixth invention).

  According to the sixth aspect of the invention, due to the elastic force of the elastic sheet, a force corresponding to the deformation of the deformation surface in the measurement target region is transmitted to the optical fiber, and the bending degree of the hetero core portion of the optical fiber is changed. Can be made.

  Therefore, the bending degree of the hetero core portion can be changed according to the load acting on the deformation surface in the measurement target region.

  In the sixth invention, the elastic sheet is formed in a polygonal shape, the local portion of the elastic sheet is one corner of the elastic sheet, and the portion that is spaced from the local portion is: It is preferable that it is each corner other than the one corner of the elastic sheet (seventh invention).

  According to the seventh aspect of the invention, the bending degree of the hetero core portion can be changed with respect to the load acting on each part of the elastic sheet. Accordingly, it is possible to detect with high sensitivity loads acting on various parts of the measurement target region.

  In the sixth invention or the seventh invention, it is preferable that the hetero-core portion of the optical fiber is fixed to a local portion of the elastic sheet in a state having a curvature (eighth invention).

  According to the eighth aspect of the invention, when the elastic deformation of the elastic sheet occurs according to the load acting on the measurement target region, it is possible to start the change in the bending degree of the heterocore portion with high responsiveness.

  In addition, as an application example, the first invention can adopt an aspect in which the measurement object is a mattress of a bedding, and the deformation surface and the measurement object region are surfaces of the mattress (9th invention). .

  According to the ninth aspect of the present invention, for example, how the load acts on the surface of the mattress in the state where the person lies down on the surface of the mattress, for example, when the person sleeps. It is possible to measure using the planar load sensor device.

  In the ninth aspect of the invention, the same aspects as those of the second to eighth aspects of the invention can be adopted. For example, the following aspects can also be adopted.

  That is, a plurality of the optical fibers, and a plurality of flexible linear members that respectively constitute the force transmission members corresponding to the plurality of optical fibers, and the plurality of flexible linear members Are arranged in different positions in the longitudinal direction of the mattress so as to extend in the width direction of the mattress along the surface of the mattress and bend as the surface of the mattress deforms at the position of the mattress. Each of the flexible linear members has a tension generated in the flexible linear member due to the deflection of the flexible linear member accompanying the deformation of the surface of the mattress. Are coupled to the hetero-core portion of the optical fiber so as to be transmitted to the optical fiber as a force that changes the degree of bending of the hetero-core portion of the optical fiber corresponding to (10th invention).

  According to the tenth aspect of the present invention, a force corresponding to the deformation of the deformation surface in the vicinity of the arrangement position of the flexible linear member is applied to the flexible linear member by the tension of each flexible linear member. Can be transmitted to the optical fiber corresponding to the above, and the bending degree of the hetero-core portion of the optical fiber can be changed.

  Therefore, the bending degree of the hetero-core portion of one or more optical fibers can be changed according to the state of the load acting on the surface of the mattress at various positions in the longitudinal direction of the mattress. As a result, the state of the load acting on the surface of the mattress can be detected at various positions in the longitudinal direction of the mattress.

  In the tenth aspect of the invention, the arrangement positions of the plurality of flexible linear members include at least one of a position facing the chest of a person lying on the surface of the mattress and a position facing the abdomen. An aspect can be employ | adopted (11th invention).

  Here, in general, due to the breathing motion of a person lying on the mattress, periodic fluctuations in the load acting on the surface of the mattress on the part facing the person's chest and the part facing the abdomen occur. Therefore, according to the eleventh aspect, it is possible to measure a periodic variation of the load according to a person's breathing motion.

  In the tenth invention or the eleventh invention, the plurality of flexible linear members may be coupled to a heterocore portion of an optical fiber disposed on one side of both side surfaces of the mattress in the width direction. Two flexible linear members, a flexible linear member and a flexible linear member connected to the hetero-core portion of the optical fiber arranged on the other side of the both sides in the width direction of the mattress, Including embodiments can be employed (the twelfth invention).

  Here, the degree of bending of the heterocore portion of each optical fiber tends to be smaller when the person's recumbent position in the width direction of the mattress is farther than when it is close to the heterocore portion.

  For this reason, when the recumbent position of the person on the surface of the mattress is biased to one side or the other side of the both sides in the width direction of the mattress, one of the two flexible linear members The bending degree of the hetero-core portion of the optical fiber corresponding to the flexible linear member is relatively large, and the bending degree of the hetero-core portion of the optical fiber corresponding to the other flexible linear member is relatively small. It will be a thing.

  Therefore, by acquiring measurement data according to the bending degree of each hetero core part with the above two optical fibers, it is possible to grasp a person's recumbent position in the width direction of the mattress based on those measurement data Become.

(A) is a perspective view of the planar load sensor apparatus of 1st Embodiment of this invention, (b) is a figure which expands and shows a part of planar load sensor apparatus of 1st Embodiment. Sectional drawing of the optical fiber which has a hetero core part and an optical transmission part. The figure which shows an example of the measurement system which uses the planar load sensor apparatus of 1st Embodiment. The graph which shows the measurement data using the planar load sensor apparatus of 1st Embodiment. The graph which shows the measurement data using the planar load sensor apparatus of 1st Embodiment. (A) is a perspective view of the planar load sensor apparatus of 2nd Embodiment of this invention, (b) is a figure which expands and shows a part of planar load sensor apparatus of 2nd Embodiment. The figure which shows an example of the measurement system which uses the planar load sensor apparatus of 2nd Embodiment. The graph which shows the measurement data using the planar load sensor apparatus of 2nd Embodiment. The graph which shows the measurement data using the planar load sensor apparatus of 2nd Embodiment. The graph which shows the measurement data using the planar load sensor apparatus of 2nd Embodiment. (A) is a perspective view of the planar load sensor apparatus of 3rd Embodiment of this invention, (b) is a figure which expands and shows a part of planar load sensor apparatus of 3rd Embodiment. The figure which shows an example of the measurement system which uses the planar load sensor apparatus of 3rd Embodiment. (A)-(c) is a graph which shows the measurement data using the planar load sensor apparatus of 3rd Embodiment.

[First Embodiment]
A first embodiment of the present invention will be described below with reference to FIGS.

  Referring to FIG. 1A, a planar load sensor device 1 according to this embodiment includes an optical fiber 2, a plurality of flexible linear members 5 connected to the optical fiber 2, an elastic sheet 7, and the like. Is provided.

  As shown in FIG. 2, the optical fiber 2 is configured by connecting optical fibers having different core diameters. The optical fiber 2 includes a hetero core portion 3 having a predetermined length (for example, 2 mm) and an axial direction of the hetero core portion 3. It includes optical transmission units 4 and 4 connected to both ends.

  Each optical transmission unit 4 is configured by an optical fiber having a core 4a having a constant diameter (for example, 9 μm) and a cladding 4b on the outer periphery thereof. 5 [mu] m) of an optical fiber having a core 3a and a clad 3b on the outer periphery thereof. The optical fiber which comprises these hetero core parts 3 and each optical transmission part 4 is a single mode optical fiber, for example.

  The optical fibers constituting the optical transmission units 4 and 4 constitute the hetero-core unit 3 such that the core 3a and the clad 3b of the hetero-core unit 3 are connected to the core 4a and the cladding 4b of each optical transmission unit 4, respectively. Both ends of the optical fiber in the axial direction are joined coaxially by fusion or the like.

  In addition, in this embodiment, although the diameter of the core 3a of the hetero core part 3 is constant, the diameter of this core 3a does not need to be constant. For example, the diameter of the core 3a may be formed so as to gradually change at the portions near both ends of the hetero core portion 3 (the diameter gradually decreases as the distance from the optical transmission portion 4 increases).

  Referring to FIG. 1A, the elastic sheet 7 is a thin sheet formed of an elastic body (for example, silicone rubber), and is formed in a square shape in this embodiment. The thickness of the elastic sheet 7 is 1 mm, for example.

  A rectangular frame-shaped frame 8 made of a member (for example, plastic) having a higher rigidity than the elastic sheet 7 is attached to the peripheral edge of the elastic sheet 7.

  In the present embodiment, the optical transmission units 4 and 4 constituting both side portions of the hetero core portion 3 of the optical fiber 2 in the axial direction are fixed to the frame 8.

  Specifically, as shown in FIG. 1A, the optical fiber 2 has one side (see FIG. 1) of the peripheral portion of the elastic sheet 7 on the back surface (lower surface in FIG. 1A) side of the elastic sheet 7. In the example shown, it is arranged so as to extend along the long side). In this case, the optical fiber 2 is disposed so that the hetero core portion 3 is located near the center of one side of the peripheral edge of the elastic sheet 7. And the optical transmission parts 4 and 4 which comprise the both sides of the axial center direction of the hetero core part 3 of the optical fiber 2 are being fixed to the flame | frame 8 with the adhesive agent etc.

  In this case, since the hetero core portion 3 is not fixed to the frame 8, the hetero core portion 3 can change the degree of bending (curvature).

  Each optical transmission unit 4 does not have to fix the entire portion along the frame 8 to the frame 8. For example, a predetermined length portion near the hetero core portion 3 of each optical transmission portion 4 may not be fixed to the frame 8.

  The flexible linear member 5 corresponds to the linear force transmission member in the present invention, and is composed of a flexible thread-like member that is difficult to expand and contract, for example, a polyester thread. A plurality of flexible linear members 5 are attached to the elastic sheet 7 as described below, and one end portion of each flexible linear member 5 is connected to the optical fiber 2 via the connecting member 9. It is connected to.

  The connecting member 9 is made of a material (for example, brass) that is less likely to bend than the elastic sheet 7 and the optical fiber 2. In the present embodiment, as shown in FIG. ). The connecting member 9 has a diameter of 3 mm, for example.

  And the hetero core part 3 of the optical fiber 2 crosses the inner side of this annular coupling member 9, and the coupling member is connected to a part near one end and a part near the other end of the hetero core part 3 in the axial direction. 9 is fixed by an adhesive or the like.

  By applying a force in a direction intersecting with the axial direction of the hetero core portion 3 to the connecting member 9, the degree of bending of the hetero core portion 3 can be changed.

  As described above, one end of each of the plurality of flexible linear members 5 is tied to the connecting member 9 fixed to the optical fiber 2 (and thus fixed). In this case, since the connecting member 9 has the same size as the length of the hetero core portion 3, one end of each of the plurality of flexible linear members 5 is a local region in the vicinity of the hetero core portion 3. In a state of being arranged so as to concentrate on the hetero core portion 3, the hetero core portion 3 is connected via the connecting member 9.

  The one end of the flexible linear member 5 may be fixed to the connecting member 9 with an adhesive or the like.

  The plurality of flexible linear members 5 are stretched so as to extend radially from the respective one end sides along the back surface of the elastic sheet 7, and are fixed to the elastic sheet 7 with an adhesive or the like. ing. In this case, each flexible linear member 5 extends so as to cross the elastic sheet 7 from a position on one side of the elastic sheet 7 to a side facing or crossing the one side. . Each flexible linear member 5 is fixed to the elastic sheet 7 so that when the elastic sheet 7 is deformed by an external load, the flexible linear member 5 follows the deformation. The

  Further, the elastic sheet 7 is provided with an opening hole 10 facing the connecting member 9 and the hetero core portion 3, and the connecting member 9 interferes with the elastic sheet 7 inside the opening hole 10. It is possible to move by the tension of the flexible linear member 5 (and consequently the degree of bending of the hetero-core portion 3 changes).

  The planar load sensor device 1 of the present embodiment is configured as described above.

  Next, a measurement method using the planar load sensor device 1 configured as described above will be described.

  In the present embodiment, the elastic sheet 7 is arranged on the deformation surface Sf so as to cover the measurement target region of the deformation surface Sf (surface deformed by the load) of the measurement object W, and in this state, the elastic sheet 7 Is attached to the measurement target region of the deformation surface Sf via the frame 8.

  In this case, the frame 8 is fixed to the peripheral portion of the measurement target region via an adhesive, a hook-and-loop fastener, a double-sided tape, and the like.

  In this case, the optical transmission parts 4 and 4 of the optical fiber 2 (parts on both sides in the axial direction of the hetero-core part 3) are fixed to the peripheral part of the measurement target region via the frame 8.

  The measurement target region is a region in which a state of a load acting on the measurement target region (a state such as whether or not a load is applied to the measurement target region) is to be detected. It is a rectangular area of almost the same size.

  And the measurement system 15 as shown in FIG. 3 is comprised, and a measurement is performed using this measurement system 15. FIG.

  The measurement system 15 includes a light source 16 that outputs light incident on the optical fiber 2, a photodetector 17 that receives light emitted from the optical fiber 2, and an output of the photodetector 17 through an AD converter (not shown). And a data processing device 18 to be captured.

  The light source 16 includes a light emitting diode (LED), a laser diode (LD), and the like, and is connected to one end of one of the optical transmission units 4 and 4 of the optical fiber 2.

  The photodetector 17 is constituted by a photodiode (PD) or the like, and is connected to the other end of the other side of the optical transmission units 4 and 4 of the optical fiber 2.

  The data processing device 18 is configured by a computer such as a personal computer.

  As described above, light is incident on the optical fiber 2 from the light source 16 of the measurement system 15 with the peripheral edge of the elastic sheet 7 attached to the deformation surface Sf of the measurement object W via the frame 8, and the optical fiber. The light emitted from 2 is detected by the photodetector 17.

  Then, the data processor 18 measures the intensity of the emitted light indicated by the output of the photodetector 17, and measures the transmission loss of light in the optical fiber 2 based on the intensity of the emitted light.

  Here, since the optical fiber 2 of the present embodiment has the hetero core part 3, a part of the light transmitted toward the hetero core part 3 through the core 4 a of the light transmission part 4 on the light source 16 side is a part of the hetero core part 3. The clad 3b is entered. As the degree of bending (curvature) of the heterocore portion 3 increases, the amount of light leaking to the outside from the cladding 3b of the heterocore portion 3 increases, so that the light transmission loss in the optical fiber 2 increases.

  Accordingly, the transmission loss of light in the optical fiber 2 depends on the degree of bending of the hetero core portion 3.

  On the other hand, the degree of bending of the heterocore portion 3 changes according to the deformation of the measurement target region of the deformation surface Sf of the measurement target W.

  More specifically, since the elastic sheet 7 of the planar load sensor device 1 is attached to the deformation surface Sf of the measurement object W as described above, the measurement target region of the deformation surface Sf is a load acting on the deformation surface Sf. When the deformation occurs, the elastic sheet 7 is elastically deformed according to the deformation so as to follow the deformation shape of the measurement target region. And any flexible linear member 5 will bend according to this elastic deformation.

  In this case, the tension generated in the flexible linear member 5 changes according to the bending of the flexible linear member 5, and as a result, a force that changes the degree of bending acts on the heterocore portion 3 of the optical fiber 2. To do.

  Further, in this case, the deformation shape of the measurement target region and the elastic sheet 7 changes according to the position where the load is applied to the measurement target region, so that the force acting on the optical fiber 2 via the connecting member 9 is changed. The size changes.

  Therefore, based on the transmission loss of light in the optical fiber 2, it is possible to detect the load state acting on the measurement target region of the deformation surface Sf of the measurement target W.

  Specific measurement examples by the planar load sensor device 1 of the present embodiment are shown in FIGS. FIG. 4 shows a specific load application position (points P1, P2, and P3 in FIG. 3) of the elastic sheet 7 in a state where the elastic sheet 7 is installed on the surface of a measurement object made of urethane resin or the like. ) Is a graph showing a measurement example when a pressing load in the thickness direction of the elastic sheet 7 is applied by a force gauge (not shown). The horizontal axis in FIG. 4 is the applied pressing load, and the vertical axis is the light transmission loss in the optical fiber 2. The transmission loss is a relative value (relative value expressed in decibels) based on the transmission loss when the load is zero (= zero).

  In this case, a graph a1 in FIG. 4 is a graph showing measurement data when the point P1 in FIG. 3 is a load application location, and a graph a2 is a measurement data when the point P2 in FIG. 3 is a load application location. The graph shown, graph a3, is a graph showing measurement data when the point P3 in FIG. In addition, each graph a1, a2, a3 has shown the measurement data in the case of increasing the applied pressure load, and the measurement data in the case of decreasing this pressure load.

  As shown in the graphs a <b> 1 to a <b> 3, the light transmission loss increases because the degree of bending of the heterocore portion 3 increases as the pressing load to be applied increases at any load application point of P <b> 1 to P <b> 3. Was confirmed.

  Further, as can be seen by comparing the graphs a1 and a2, the flexible linear member 5 is applied when a pressing load is applied at a load application point (point P2) on the flexible linear member 5. It can be seen that the sensitivity of the change in the transmission loss of light with respect to the change in the pressing load is higher than that in the case where the pressing load is applied at the load application point (point P1) that is not above.

  Further, as can be seen by comparing the graphs a1 and a3, when the load application point is closer to the heterocore part 3 (point P2) than when the load application point is far from the heterocore part 3 (point P3), It can be seen that the sensitivity of changes in optical transmission loss is increased.

  FIG. 5 shows an elastic body in a state where the elastic body sheet 7 is placed on the surface of a measurement object made of urethane resin or the like, and the frame 8 at the peripheral edge of the elastic body sheet 7 is fixed to the measurement object. A specific load application point (the point P1 in FIG. 3) of the sheet 7 is picked up for a predetermined time (for example, 2 seconds) (in other words, the load application point of the elastic sheet 7 is protruded to the surface side). It is a graph which shows the example of a measurement at the time of repeating giving a load to a load provision location. The horizontal axis of FIG. 4 is the elapsed time, and the vertical axis is the transmission loss of light in the optical fiber 2. Note that the transmission loss is a relative value (relative value expressed in decibels) based on the transmission loss when the load is zero as in the case of FIG. 5 (= zero).

  As can be seen with reference to the graph of FIG. 5, it can be seen that by picking up the elastic sheet 7, the degree of bending of the hetero-core portion 3 increases, thereby increasing the light transmission loss.

  Note that the light transmission loss slightly decreases during the picking period of the elastic sheet 7. This is considered because the elastic sheet 7 is extended.

  As described above, since the transmission loss of light in the optical fiber 2 changes according to the load state acting on the elastic sheet 7, the deformation of the measurement object W on which the elastic sheet 7 is arranged based on the transmission loss. A load state acting on the surface Sf can be detected.

  Here, some modifications related to the first embodiment described above will be described.

  In this embodiment, the frame 8 is provided. However, the frame 8 may be omitted, and the peripheral edge of the elastic sheet 7 may be directly attached to the peripheral edge of the measurement target region.

  Moreover, you may fix directly the both-sides part of the axial center direction of the hetero core part 3 of the optical fiber 2 to the peripheral part of a measurement object area | region.

  Moreover, you may make it arrange | position the hetero core part 3 of the optical fiber 2 to the side of this measurement object area | region in the location a little away from the peripheral part of a measurement object area | region.

  The flexible linear member 5 may be embedded in the elastic sheet 7. Further, the connecting member 9 may be omitted, and one end portion of the flexible linear member 5 may be directly fixed to the heterocore portion 3 with an adhesive or the like.

  When the measurement target region is a relatively narrow region, the number of flexible linear members 5 may be one.

  The flexible linear member 5 may be made of metal.

  The shape of the elastic sheet 7 may be a shape other than a square shape. For example, it may be a polygonal shape other than a quadrangle, such as a triangle or a pentagon, or a circular shape, an elliptical shape, a rhombus shape, or the like.

  Further, the elastic sheet 7 may be omitted, and the flexible linear member 5 may be attached to the measurement target region of the measurement target W.

  Supplementally, in the planar load sensor device 1 of the present embodiment, the elastic body sheet 7 can be regarded as a measurement object. In this case, the flexible linear member 5 is directly attached to the measurement object (here, the elastic sheet 7), and both side portions in the axial direction of the hetero core portion 3 of the optical fiber 2 (light transmission portion). 4 and 4) are attached to the measurement object at the periphery of the measurement object region (here, the front surface or the back surface of the elastic sheet 7).

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIGS.

  With reference to FIG. 6A, the planar load sensor device 21 of this embodiment includes an optical fiber 2 and an elastic sheet 22 connected to the optical fiber 2.

  The structure of the optical fiber 2 is the same as that of the optical fiber according to the first embodiment described with reference to FIG. Therefore, the description in this embodiment is omitted.

  The elastic sheet 22 corresponds to a planar force transmission member in the present invention. The elastic sheet 22 is a thin sheet formed of an elastic body (for example, silicone rubber), and is formed in a square shape in the present embodiment. The thickness of the elastic sheet 22 is, for example, 0.5 mm.

  A rectangular frame-shaped frame 23 made of a member (for example, plastic) having a rigidity higher than that of the elastic sheet 22 is disposed at the peripheral portion of the elastic sheet 22, and the peripheral portion of the elastic sheet 22 is disposed on the frame 23. Are fixed by an adhesive 24a.

  In the present embodiment, three corners of the peripheral edge of the elastic sheet 22 are fixed to the frame 23 by the adhesive 24a.

  And in this embodiment, the hetero core part 3 of the optical fiber 2 is being fixed to the peripheral part of the elastic-body sheet | seat 22. As shown in FIG. Furthermore, optical transmission parts 4 and 4 constituting both side parts in the axial direction of the hetero core part 3 of the optical fiber 2 are fixed to the frame 23.

  Specifically, as shown in FIG. 6 (b), the hetero-core portion 3 of the optical fiber 2 is the remaining one corner portion (local portion) that is not fixed to the frame 23 among the peripheral portion of the elastic sheet 22. ) With an adhesive 24b. In this case, in the present embodiment, the heterocore portion 3 is fixed to the one corner portion of the elastic sheet 22 in a slightly bent state (a state having a slight curvature).

  Then, the portions near the hetero core portion 3 of the optical transmission portions 4 and 4 constituting both side portions in the axial direction of the hetero core portion 3 of the optical fiber 2 are fixed to the frame 23. The optical transmission parts 4 and 4 are fixed to the frame 23 by, for example, an adhesive 24c.

  In this case, since the hetero core portion 3 and the corner portion of the elastic sheet 22 to which the hetero core portion 3 is fixed are not fixed to the frame 23, the bending of the hetero core portion 3 is caused by the elastic force generated by the elastic deformation of the elastic sheet 22. It is possible to change the degree (curvature).

  The planar load sensor device 21 of the present embodiment is configured as described above.

  Next, a measurement method using the planar load sensor device 21 configured as described above will be described.

  In the present embodiment, the elastic sheet 22 is disposed on the deformation surface Sf so as to cover the measurement target region of the deformation surface Sf (surface deformed by the load) of the measurement object W, and the frame 23 is deformed in this state. It is attached to the measurement target area of the surface Sf.

  In this case, the frame 23 is fixed to the peripheral portion of the measurement target region via an adhesive, a hook-and-loop fastener, a double-sided tape, and the like.

  In this case, the portion of the elastic sheet 22 fixed to the frame 23 (three corners other than the corner to which the hetero core portion 3 is fixed) is fixed to the peripheral portion of the measurement target region via the frame 23. Will be. In addition, the optical transmission parts 4 and 4 of the optical fiber 2 (parts on both sides in the axial direction of the hetero-core part 3) are fixed to the measurement target region via the frame 23.

  The measurement target region is a region where a load state acting on the measurement target region (a state such as whether or not a load is applied to the measurement target region) is to be detected. In the present embodiment, the measurement target region is substantially the same as the elastic sheet 22. It is a square area of the same size.

  Then, a measurement system 25 as shown in FIG. 7 is configured, and measurement is performed using this measurement system 25.

  This measurement system 25 includes a light source 26 that outputs light incident on the optical fiber 2, a photodetector 27 that receives light emitted from the optical fiber 2, and an output of the photodetector 27 via an AD converter (not shown). And a data processing device 28 to be captured.

  The light source 26 includes a light emitting diode (LED), a laser diode (LD), and the like, and is connected to one end of one of the optical transmission units 4 and 4 of the optical fiber 2.

  The photodetector 27 is configured by a photodiode (PD) or the like, and is connected to the other end on the other side of the optical transmission units 4 and 4 of the optical fiber 2.

  The data processing device 28 is configured by a computer such as a personal computer.

  As described above, light is incident on the optical fiber 2 from the light source 26 of the measurement system 25 with the peripheral edge of the elastic sheet 22 attached to the deformation surface Sf of the measurement object W via the frame 23, and the optical fiber. The light emitted from 2 is detected by the photodetector 27.

  Then, the data processor 28 measures the intensity of the emitted light indicated by the output of the photodetector 27, and measures the transmission loss of light in the optical fiber 2 based on the intensity of the emitted light.

  Here, the transmission loss of light in the optical fiber 2 of the present embodiment corresponds to the degree of bending of the hetero-core portion 3 of the optical fiber 2 as described in the first embodiment.

  On the other hand, in the present embodiment, the degree of bending of the heterocore portion 3 changes according to the deformation of the measurement target region of the deformation surface Sf of the measurement target W.

  More specifically, since the elastic sheet 22 of the planar load sensor device 21 is attached to the deformation surface Sf of the measurement target W as described above, the deformation of the measurement target region of the deformation surface Sf (the measurement target region) The elastic sheet 22 is elastically deformed so as to follow the deformed shape of the measurement target region in accordance with the deformation according to the load acting on the material.

  In this case, the degree of bending of the hetero core portion 3 of the optical fiber 2 is determined by the elastic force generated by the elastic sheet 22 in accordance with the deformation of the measurement target region of the measurement target W (and hence the elastic deformation of the elastic sheet 22). The force that changes is applied.

  Further, in this case, the deformation shape of the measurement target region and the elastic sheet 22 changes according to the position where the load is applied to the measurement target region, so that the magnitude of the force acting on the heterocore portion 3 of the optical fiber 2 or the like Changes.

  Therefore, based on the transmission loss of light in the optical fiber 2, it is possible to detect the load state acting on the measurement target region of the deformation surface Sf of the measurement target W.

  Moreover, in this embodiment, the hetero core part 3 of the optical fiber 2 is bonded to the corners of the elastic sheet 22 in a slightly bent state.

  For this reason, the bending degree of the hetero core part 3 can be changed with a quick response to the elastic deformation of the elastic sheet 22, and thus the transmission loss of light in the optical fiber 2 can be changed with a quick response.

  Specific measurement examples by the planar load sensor device 21 of the present embodiment are shown in FIGS. FIGS. 8 to 10 show specific load-applying portions (points P11 to P19 in FIG. 7) of the elastic sheet 22 in a state where the elastic sheet 22 is installed on the surface of the measurement object made of urethane resin or the like. It is a graph which shows the example of a measurement when the pressing load of the normal line direction of this elastic body sheet 22 is provided to the location) with the force gauge which is not illustrated. The horizontal axis in FIGS. 8 to 10 is the applied pressure load, and the vertical axis is the transmission loss of light in the optical fiber 2. The transmission loss is a relative value (relative value expressed in decibels) based on the transmission loss when the load is zero (= zero).

  In this case, graphs a11 to a13 in FIG. 8 are graphs showing measurement data when the points P11, P12, and P13 in FIG. 7 are applied load points, and graphs a14 to a16 in FIG. A graph showing measurement data when the points P14, P15, and P16 are applied load points, and graphs a17 to a19 in FIG. 10 are measurement data when the points P17, P18, and P19 of FIG. It is a graph to show. In addition, each graph a11-a19 has shown the measurement data in the case of increasing the applied pressure load, and the measurement data in the case of decreasing this pressure load.

  As shown in graphs a <b> 11 to a <b> 19, at any load application location of P <b> 11 to P <b> 19, the greater the pressing load to be applied, the greater the degree of bending of the heterocore portion 3, thereby increasing the light transmission loss. Was confirmed.

  Further, as can be seen by comparing the graphs a11, a15, and a19 with other graphs, when viewed from the heterocore portion 3, at the load application points (points P11, P15, and P19) in the diagonal direction of the elastic sheet 22, It can be seen that the sensitivity of the change in light transmission loss to the change in load is high.

  Further, as can be seen by comparing the graphs a13, a16, a17, and a18 with the graphs a12 and a14, the elasticity connected to the corners of the elastic body sheet 22 where the heterocore portion 3 is disposed as viewed from the heterocore portion 3. The load application locations (points P13, P16, P17, P18) at positions along the two sides of the body sheet 22 are more than the load application locations (points P12, P14) that are not positions along the two sides. It can be seen that the sensitivity of the change in the transmission loss of light with respect to the change in load increases.

  Here, some modifications related to the first embodiment described above will be described.

  In the present embodiment, the frame 23 is provided, but the frame 23 is omitted, and the peripheral portion of the elastic sheet 22 (the portion having a gap from the corner to which the heterocore portion 3 is fixed) is directly connected to the periphery of the measurement target region. You may make it attach to a part.

  Further, both side portions of the optical fiber 2 in the axial direction of the heterocore portion 3 may be directly fixed to the peripheral portion of the measurement target region, or may be fixed to a member separate from the measurement target W.

  Further, the shape of the elastic body sheet 22 may be a shape other than a square shape. For example, it may be a polygonal shape other than a quadrangle, such as a triangle or a pentagon, or a circular shape, an elliptical shape, a rhombus shape, or the like.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIGS.

  The planar load sensor device 31 of the present embodiment is configured to detect a load state acting on the surface (upper surface) of the mattress Mt using the mattress Mt of the bedding as a measurement object. In this case, the surface (upper surface) of the mattress Mt corresponds to the deformation surface and the measurement target region.

  Specifically, the planar load sensor device 31 includes a plurality of optical fibers 2 and a plurality of flexible linear members 32 respectively connected to the respective optical fibers 2. In the present embodiment, the planar load sensor device 31 includes three pairs of the optical fiber 2 and the flexible linear member 32.

  The structure of each optical fiber 2 is the same as the optical fiber of the first embodiment described with reference to FIG. Therefore, the description in this embodiment is omitted.

  Each flexible linear member 32 corresponds to the linear force transmission member in the present invention, and is made of a flexible thread-like member that is difficult to expand and contract, for example, a polyester thread.

  The three flexible linear members 32, 32, 32 are arranged at predetermined positions so as to extend in parallel to each other in the width direction of the mattress Mt with a space in the longitudinal direction of the mattress Mt. Yes.

  These flexible linear members 32, 32, 32 are arranged at positions facing the human chest, facing the pigeon tail, and facing the abdomen when a person lies on the mattress Mt. is there. In the following description, the flexible linear member 32 at a position facing the human chest, the flexible linear member 32 at a position facing the pigeon tail, and the flexible linear member 32 at a position facing the abdomen are distinguished. In each case, they are represented by reference numerals 32a, 32b, 33c. The optical fibers 2 corresponding to the flexible linear members 32a, 32b, and 32c are respectively denoted by reference numerals 2a, 2b, and 2c.

  In the present embodiment, each flexible linear member 32 is disposed inside the mattress Mt so as to extend along the surface near the surface of the mattress Mt. One end of each flexible linear member 32 is fixed to one side surface Mt1 or the other side surface Mt2 of both side surfaces Mt1 and Mt2 in the width direction of the mattress Mt by an adhesive or the like.

  More specifically, in the present embodiment, the flexible linear members 32a and 32c at positions facing two of the three flexible linear members 32, 32, and 32, for example, a person's chest and abdomen, respectively. One end of the side surface Mt1 of the mattress Mt is fixed to the side surface Mt1, and the remaining one flexible linear member 32b (the flexible linear member 32b at a position facing a human pigtail) One end of the side surface Mt2 opposite to Mt1 is fixed to the side surface Mt2.

  In addition, notches ma and mc are formed on the upper side of the side surface Mt2 of the mattress Mt so that the other ends of the flexible linear members 32a and 32c protrude from the upper side of the side surface Mt1 of the mattress Mt. A notch mb is formed by projecting the other end of the flexible linear member 32b.

  In each of the notches ma, mb, and mc, the hetero-core portion 3 of the optical fiber 2 corresponding to each of the flexible linear members 32a, 32b, and 32c is connected to each of the flexible linear members 32a, 32b, and 32c. It is fixed to each other end.

  More specifically, the optical fiber 2a corresponding to the flexible linear member 32a is arranged on the side surface Mt2 side of the mattress Mt, and extends in the longitudinal direction of the mattress Mt so that the hetero core portion 3 faces the notch ma. ing. And the optical transmission parts 4 and 4 are being fixed to the side surface Mt2 of the mattress Mt with the adhesive etc. in the both sides of the axial direction of the hetero core part 3 of the optical fiber 2a. Further, the other end portion of the stretched flexible linear member 32a is fixed to the center portion of the hetero-core portion 3 of the optical fiber 2a with an adhesive or the like at the notch portion ma.

  Similarly, the optical fiber 2c corresponding to the flexible linear member 32c is disposed on the side surface Mt2 side of the mattress Mt, and extends in the longitudinal direction of the mattress Mt so that the hetero core portion 3 faces the notch mc. Yes. And the optical transmission parts 4 and 4 are being fixed to the side surface Mt2 of the mattress Mt with the adhesive agent etc. in the both sides of the axial direction of the hetero core part 3 of the optical fiber 2c. Further, the other end portion of the stretched flexible linear member 32c is fixed to the center portion of the hetero-core portion 3 of the optical fiber 2c with an adhesive or the like at the notch portion mc.

  The optical fiber 2b corresponding to the flexible linear member 32b is disposed on the side surface Mt1 side of the mattress Mt, and extends in the hand direction of the mattress Mt so that the hetero core portion 3 faces the notch mb. . And the optical transmission parts 4 and 4 are being fixed to the side surface Mt2 of the mattress Mt with the adhesive agent etc. in the both sides of the axial direction of the hetero core part 3 of the optical fiber 2b. Further, the other end portion of the stretched flexible linear member 32b is fixed to the center portion of the hetero-core portion 3 of the optical fiber 2c by an adhesive or the like at the notch portion mc.

  As described above, each flexible linear member 32 c arranged on the mattress Mt is connected to the hetero core portion 3 of the optical fiber 2, so that the surface (upper surface) of the mattress Mt corresponds to each flexible linear member 32. When the flexible linear member 32 is bent when elastically deformed at the arrangement location, the tension of the flexible linear member 32 causes the hetero core portion 3 of the optical fiber 2 corresponding to the flexible linear member 32 to bend. The degree of bending will change.

  The planar load sensor device 31 of the present embodiment is configured as described above.

  Next, a measurement method using the planar load sensor device 31 configured as described above will be described.

  In the present embodiment, a measurement system 35 as shown in FIG. 12 is configured. Then, as shown in the figure, the measurement is performed with a person lying on the mattress Mt.

  The measurement system 35 includes a light source 36 that outputs light incident on each optical fiber 2, a photodetector 37 that receives light emitted from each optical fiber 2, and an output (for each optical fiber 2). And a data processing device 38 that takes in an output (not shown) through an AD converter (not shown).

  The light source 36 includes a light emitting diode (LED), a laser diode (LD), and the like, and is connected to one end of one of the optical transmission units 4 and 4 of each optical fiber 2.

  The photodetector 37 is configured by a photodiode (PD) or the like, and is connected to the other end of the other of the optical transmission units 4 and 4 of each optical fiber 2.

  The data processing device 38 is configured by a computer such as a personal computer.

  A person lies on the surface of the mattress Mt as shown in FIG. In this case, the person lies on the surface of the mattress Mt so that the chest, pigeon tail, and abdomen are positioned directly above the flexible linear members 32a, 32b, and 32c, respectively.

  In this state, light is incident on each optical fiber 2 from the light source 36 of the measurement system 35, and light emitted from each optical fiber 2 is detected by the photodetector 37.

  Then, the data processor 38 measures the intensity of the emitted light for each optical fiber 2 indicated by the output of the light detector 37, and based on the intensity of the emitted light, the transmission loss of light in each optical fiber 2 and the like. It is measured.

  Here, as described in the first embodiment, each optical fiber 2 of the present embodiment has a light transmission loss in the optical fiber 2 in accordance with the bending degree of the hetero-core portion 3.

  On the other hand, in the present embodiment, the bending degree of the hetero core portion 3 of each optical fiber 2 is determined by the deformation of the surface (deformation surface) of the mattress Mt in the vicinity of the position where the flexible linear member 32 corresponding to the optical fiber 2 is disposed. It changes according to.

  More specifically, a load acts on the surface (upper surface) of the mattress Mt due to the weight of a person lying on the mattress Mt or a breathing motion, and the surface of the mattress Mt is elastically deformed according to the load. Then, each flexible linear member 32 bends according to the elastic deformation, and the bending degree of the hetero-core portion 3 of the optical fiber 2 corresponding to the flexible linear member 32 due to the tension generated according to the bending. Changes.

  Therefore, based on the transmission loss of light in each optical fiber 2, it is possible to detect a load state acting on the surface (upper surface) of the mattress Mt due to the weight of the person lying on the surface of the mattress Mt or the breathing motion. it can.

  In this case, in particular, in the surface of the mattress Mt, the location facing the human breast (location of the flexible linear member 32a) and the location facing the stomach (location of the flexible linear member 32c). Due to a person's breathing motion, periodic fluctuations in the load acting on these locations occur. Eventually, periodic fluctuations in the bending degree of the respective heterocore portions 3 and 3 of the optical fibers 2a and 2c corresponding to the flexible linear members 32a and 32c occur.

  For this reason, in particular, by observing the time change of the transmission loss of light in the optical fibers 2a and 2c, it is possible to grasp the breathing state of a person lying on the mattress Mt.

  In the present embodiment, each of the heterocore portions 3 of the optical fibers 2a and 2c and the heterocore portion 3 of the optical fiber 2b are disposed on the opposite sides in the width direction of the mattress Mt. Based on the light transmission loss in the optical fiber 2b and the light transmission loss in the optical fiber 2b, it is possible to roughly grasp the position of the person lying in the width direction of the mattress Mt.

  That is, the degree of bending of the heterocore portion 3 of each optical fiber 2 tends to be smaller when the person's recumbent position in the width direction of the mattress Mt is farther than when it is close to the heterocore portion 3.

  For this reason, when the recumbent position of the person on the mattress Mt is a position near the side surface Mt1 of the both side surfaces Mt1 and Mt2 in the width direction of the mattress Mt, the hetero core portions 3 of the optical fibers 2a and 2c On the other hand, the degree of bending becomes relatively small (as a result, the transmission loss of light in the optical fibers 2a and 2c becomes relatively small), while the degree of bending of the hetero-core portion 3 of the optical fiber 2b becomes relatively large ( As a result, the transmission loss of light in the optical fiber 2b becomes relatively large).

  On the other hand, when the position of the person lying on the mattress Mt is a position closer to the side face Mt2 of the both side faces Mt1 and Mt2 in the width direction of the mattress Mt, each of the hetero core portions 3 of the optical fibers 2a and 2c On the other hand, the degree of bending becomes relatively large (as a result, the transmission loss of light in the optical fibers 2a and 2c becomes relatively large), while the degree of bending of the hetero-core portion 3 of the optical fiber 2b becomes relatively small ( As a result, the transmission loss of light in the optical fiber 2b is relatively small).

  Therefore, based on the transmission loss of light in the optical fiber 2a or 2c and the transmission loss of light in the optical fiber 2b, it is possible to roughly grasp the position of a person lying in the width direction of the mattress Mt.

  Specific measurement examples by the planar load sensor device 31 of the present embodiment are shown in FIGS. FIGS. 13A to 13C are graphs showing measurement examples in a state where a person lies on the mattress Mt at a substantially central position in the width direction of the mattress Mt. In this case, the lying state of the person on the mattress Mt is a state in which the chest, pigeon tail, and abdomen are lying on the prone side, with the flexible linear members 32a, 32b, and 32c facing each other.

  FIGS. 13A to 13C are measurement examples of light transmission loss in the optical fibers 2a, 2b, and 2c, respectively. 13A to 13C, the horizontal axis represents elapsed time, and the vertical axis represents light transmission loss in each optical fiber 2. The transmission loss is a relative value (relative value expressed in decibels) based on the transmission loss when the load is zero (= zero).

  As shown in the graphs of FIGS. 13A and 13C, the light transmission loss in the optical fiber 2a corresponding to the flexible linear member 32a facing the human chest and the possibility of facing the human belly. The transmission loss of light in the optical fiber 2c corresponding to the flexible linear member 32c causes periodic fluctuations due to human breathing motion.

  In this case, the increase and decrease of the load acting on the upper surface of the mattress Mt at the position facing the person's chest and the position facing the abdomen due to the person's breathing motion is in an opposite phase relationship at both the positions. Since it occurs (the load decreases at the other part when the load increases at one part), the optical fibers 2a and 2c undergo periodic fluctuations in the optical transmission loss in an opposite phase relationship.

  Here, some modifications related to the first embodiment described above will be described.

  In the present embodiment, the mattress Mt includes the three flexible linear members 32. However, the mattress Mt may include two or four or more flexible linear members 32. For example, any one of the flexible linear members 32a, 32b, and 32c may be omitted, or more flexible linear members may be added.

  In the present embodiment, the hetero core portions 3 of the optical fibers 2a and 2c and the hetero core portion 3 of the optical fiber 2b are arranged on the opposite sides in the width direction of the mattress Mt. You may arrange | position on the same side surface side in the width direction of the mattress Mt.

  Moreover, the flexible linear member 32 may be arrange | positioned in the state exposed to the surface of the mattress Mt.

  In each of the embodiments described above, the optical fiber 2 emits light incident from one end from the other end. For example, one end of the hetero core portion 3 of light (one end opposite to the light incident side). Alternatively, a mirror may be provided in the middle of the optical transmission unit 4 connected to the one end, and the light that has entered the heterocore unit 3 may be reflected by the mirror and then returned to the entrance side.

  In addition, the core 3 a of the heterocore unit 3 may be formed with a diameter larger than the diameter of the core 4 a of the optical transmission unit 4.

  DESCRIPTION OF SYMBOLS 1, 21, 31 ... Planar load sensor apparatus, 2 ... Optical fiber, 3 ... Hetero core part, 4 ... Optical transmission part 4, 3a, 4a ... Core, 3b, 4b ... Cladding, 5, 32 ... Flexible linear form Member (force transmission member), 7 ... elastic sheet, 9 ... connecting member, 22 ... elastic sheet (force transmission member), W ... measurement object, Mt ... mattress.

Claims (12)

A planar load sensor device for detecting a load acting on a deformation surface of a measurement object having a deformation surface deformed by a load,
An optical transmission part having a core and a cladding, and a hetero core part having a core and a cladding respectively connected to the core and the cladding of the optical transmission part, wherein the core of the hetero core part is formed with a different diameter from the core of the optical transmission part And an optical fiber in which the hetero-core portion is disposed at a peripheral portion or a side of a measurement target region of the deformation surface of the measurement target;
A linear or planar force transmission member configured to transmit a force that changes the degree of bending of the hetero-core portion of the optical fiber to the optical fiber according to the deformation of the deformation surface in the measurement target region; A planar load sensor device comprising: The planar load sensor device according to claim 1,
The force transmission member is configured by one or a plurality of flexible linear members that extend along the deformation surface in the measurement target region and are stretched so as to bend along with the deformation of the deformation surface.
The flexible linear member is configured to apply a tension generated in the flexible linear member due to bending of the flexible linear member accompanying deformation of the deformation surface in the measurement target region to a degree of bending of the hetero core portion. A planar load sensor device coupled to the optical fiber so as to transmit the force to the optical fiber as a force for changing the power. In the planar load sensor device according to claim 2,
The force transmission member is composed of a plurality of flexible linear members, and the plurality of flexible linear members are arranged so that each one end portion is concentrated at the arrangement position of the hetero-core portion of the optical fiber. The planar load sensor device is connected to the hetero core portion and is arranged so as to extend radially from the one end side along the deformation surface in the measurement target region. In the planar load sensor device according to claim 3,
And further comprising a connecting member fixed to the optical fiber at two portions, ie, a portion near one end in the axial direction of the hetero-core portion and a portion near the other end. One end of each member is fixed to the connecting member, and the member is connected to the hetero-core portion of the optical fiber via the connecting member. In the planar load sensor device according to any one of claims 2 to 4,
The elastic sheet further includes an elastic sheet that is disposed so as to cover the deformation surface in the measurement target region and elastically deforms following the deformation of the deformation surface, and the flexible linear member is attached to the elastic sheet. A planar load sensor device. The planar load sensor device according to claim 1,
The force transmission member is arranged to cover the deformation surface in the measurement target region, and is configured by an elastic sheet that elastically deforms following the deformation of the deformation surface,
The elastic sheet transmits the elastic force generated by the elastic deformation of the elastic sheet accompanying the deformation of the deformation surface in the measurement target region to the optical fiber as a force that changes the bending degree of the hetero core portion. In addition, a local part of the peripheral part of the elastic sheet is connected to the hetero-core part of the optical fiber, and a part of the peripheral part of the elastic sheet that is spaced from the local part is the measurement target region. A planar load sensor device that is fixed to the object to be measured at a peripheral edge thereof. The planar load sensor device according to claim 6,
The elastic sheet is formed in a polygonal shape, and the local portion of the elastic sheet is one corner of the elastic sheet, and one or more portions that are spaced from the local portion are elastic A planar load sensor device, which is each corner other than the one corner of the body sheet. The planar load sensor device according to claim 6 or 7,
The planar load sensor device, wherein the hetero-core portion of the optical fiber is fixed to a local portion of the elastic sheet in a state having a curvature. The planar load sensor device according to claim 1,
The planar load sensor device, wherein the measurement object is a mattress of a bedding, and the deformation surface and the measurement object region are surfaces of the mattress. The planar load sensor device according to claim 9, wherein
A plurality of the optical fibers, and a plurality of flexible linear members respectively constituting the force transmission member corresponding to each of the plurality of optical fibers,
Each of the plurality of flexible linear members extends in the width direction of the mattress along the surface of the mattress at different arrangement positions in the longitudinal direction of the mattress, and the surface of the mattress at the arrangement position It is arranged to bend with the deformation of
Each flexible linear member corresponds to the flexible linear member with the tension generated in the flexible linear member due to the deflection of the flexible linear member accompanying the deformation of the surface of the mattress. A planar load sensor device, wherein the planar load sensor device is connected to the hetero-core portion of the optical fiber so as to transmit the force to the optical fiber as a force that changes the degree of bending of the hetero-core portion of the optical fiber. The planar load sensor device according to claim 10,
The arrangement positions of the plurality of flexible linear members include at least one of a position facing a breast of a person lying on the surface of the mattress and a position facing the abdomen. Load sensor device. The planar load sensor device according to claim 10 or 11,
The plurality of flexible linear members include a flexible linear member connected to a heterocore portion of an optical fiber disposed on one side of both side surfaces in the width direction of the mattress, and a width direction of the mattress. A planar load sensor device comprising: a flexible linear member connected to a hetero-core portion of an optical fiber disposed on the other side of the two side surfaces of the optical fiber and two flexible linear members.