JP5961991B2 - Power generation element and monitoring system - Google Patents

Description

  The present invention relates to a power generation element and a monitoring system.

  In recent years, the construction of a structural health monitoring system that detects damage to buildings due to earthquakes or changes over time has been underway. The structural health monitoring system includes a sensor that detects damage, a battery that drives the sensor, and an analysis device, and the sensor outputs data to the analysis device when vibrations or the like generated in the building are detected. Further, the analysis device issues a warning or the like according to the data analysis result. In addition, the structural health monitoring system can intermittently acquire data with a sensor, and can transmit the data collected every time the data is acquired or every predetermined amount to the analysis device.

  Here, in the case where the sensor intermittently transmits data, power for sensor operation and data transmission is required periodically, and thus the battery needs to be replaced every several months. For this reason, when constructing a structural health monitoring system, it is necessary to consider the man-hours for battery replacement and the cost for replacement.

  Therefore, it is considered that the conventional structural health monitoring system extends the usage time of the sensor by connecting the power generating element to the battery and using it while charging the battery. This is because the power consumption can be greatly reduced if the sensor is put in the sleep state except when data is intermittently transmitted, so that even if the power generation element cannot generate a large amount of power, the sensor usage time can be sufficiently reduced. This is because it can be extended.

  As a power generation element connected to a battery, there is a device that generates power by using energy inherent in the environment, for example, an air flow such as wind, vibration, sunlight, heat, electromagnetic waves, or the like. With such a power generation element, it is possible to generate necessary power without giving a load to the environment.

  For example, power generation using airflow has been put into practical use as wind power generation by a large-scale windmill, but for low-power power generation used in structural health monitoring systems, power is generated by vibrating a piezoelectric sheet with wind. A method has been proposed.

  As a conventional example of a power generating element using a piezoelectric sheet, a configuration in which one end of a strip-shaped piezoelectric sheet is fixed and an end of a sheet-like pendulum (Pendulum) is attached to the other end via a hinge is known. . In this power generation element, the eddy current generated when the wind blows from the fixed end toward the pendulum oscillates the pendulum that looks like a leaf and vibrates the piezoelectric sheet connected to the pendulum to generate power.

VERTICAL-STALK FLAPPING-LEAF GENERATOR FOR WIND ENERGY HARVESTING (Proceedings of the ASME 2009 Conference) SMIT, SMIT PRODUCTS PROJECTS, [on line], [Search December 5, 2011], Internet <URL: http://s-m-i-t.com/#projects_target>

However, in the conventional power generating element, in an environment where the air flow hardly fluctuates, the position of the pendulum is maintained in a specific posture, so that the bending amount and the bending direction of the piezoelectric sheet are also constant. In this state, the amount of power generated by the piezoelectric sheet is reduced. Therefore, it has been desired to develop a power generation device that can efficiently generate power by efficiently vibrating a piezoelectric sheet.
This invention is made | formed in view of such a situation, and it aims at generating efficiently the electric power supplied to a sensor using a wind force.

According to one embodiment of the present invention, a piezoelectric sheet having a deformable piezoelectric material and having a proximal end fixed, a fin connected to the distal end portion of the piezoelectric sheet and receiving wind, and a distal end portion of the piezoelectric sheet And a connecting member that connects the piezoelectric sheet and a portion disposed on the tip end side of the piezoelectric sheet from the center of the fin.

  Since the force that the fin receives from the wind can be made different between the distal end side and the proximal end side, the position of the fin is easily changed. Since the piezoelectric sheet can be reliably vibrated, the necessary power can be stably obtained.

FIG. 1 is a diagram illustrating an example of a schematic configuration of a monitoring system according to an embodiment of the present invention. FIG. 2 is a plan view showing an example of the power generation element according to the embodiment of the present invention. FIG. 3A is a developed view showing an example of a hinge that is a connecting member according to the embodiment of the present invention. FIG. 3B is a perspective view showing an example of a hinge that is a connecting member according to the embodiment of the present invention. FIG. 4 is a schematic diagram for explaining an example of the operation of the power generation element according to the embodiment of the present invention. (Part 1) FIG. 5 is a schematic diagram for explaining an example of the operation of the power generating element according to the embodiment of the present invention. (Part 2) FIG. 6 is a schematic diagram for explaining an example of the operation of the power generating element according to the embodiment of the present invention. (Part 3) FIG. 7 is a schematic diagram for explaining an example of the operation of the power generating element according to the embodiment of the present invention. (Part 4) FIG. 8 is a diagram illustrating an example of a voltage waveform output from the power generation element according to the embodiment of the present invention and a voltage waveform of a comparative example. FIG. 9 is a diagram showing a schematic configuration of a power generating element as a comparative example of FIG. FIG. 10 is a diagram illustrating an example of a time change of charge in the charging circuit of the power generation device according to the embodiment of the present invention. FIG. 11 is a diagram illustrating an application example of the monitoring system according to the embodiment of the present invention. FIG. 12 is a diagram illustrating another application example of the monitoring system according to the embodiment of the present invention. FIG. 13 is a diagram showing still another application example of the monitoring system according to the embodiment of the present invention. FIG. 14 is a developed view of a hinge that is a connecting member according to a modified example of the present invention. (Part 1) FIG. 15 is a development view of a hinge that is a connecting member according to a modified example of the present invention. (Part 2) FIG. 16 is a development view of a hinge that is a connecting member according to a modified example of the present invention. (Part 3)

The objects and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.
The foregoing general description and the following detailed description are exemplary and explanatory only and are not intended to limit the invention.

  FIG. 1 shows a schematic structure of a structural health monitoring system as an example of a monitoring system. The structural health monitoring system 1 includes a sensor 2 that detects the state of a structure such as a building, a battery 3 that supplies power to the sensor 2, and a power generation device 4 that charges the battery 3. Furthermore, in the structural health monitoring system 1, an analysis device (not shown) that receives and processes data output from the sensor 2 is connected to the sensor 2 by wire or wirelessly.

  Here, the power generation device 4 includes a charging circuit 5 and a power generation element 6. As shown in the plan views of FIGS. 1 and 2, the power generating element 6 has a fixed end 10 fixed to a wall of a building or the like. The base end of the piezoelectric sheet 11 is fixed to the fixed end 10. The piezoelectric sheet 11 has a strip shape, and a wind receiving fin 13 is connected to a tip portion thereof via a flexible hinge 12 that is a connecting member. The current output from the piezoelectric sheet 11 is input to the charging circuit 5 electrically connected through the fixed end 10. The charging circuit 5 includes a rectifier circuit 15 configured by a diode bridge, and is connected to a battery via a DC / DC converter 17 after passing through a capacitor 16.

  As the piezoelectric sheet 11, for example, a thin film piezoelectric material laminated with polyester is used. Examples of the thin film piezoelectric element material include PVDF (Polyvinylidene fluoride). By laminating the thin film piezoelectric element material, a repulsive force against the bending of the piezoelectric sheet (force to return to the original) is easily generated.

  As shown in a developed view in FIG. 3A, the flexible hinge 12 is made of a rectangular thin plate-like member. As shown in the perspective views of FIG. 1 and FIG. 3B, the hinge 12 is formed by bending a thin plate-like member at the center, and one end is bonded to the tip of the piezoelectric sheet 11. Further, as shown in FIG. 1, the hinge 12 is disposed from the bonding portion 21 with the piezoelectric sheet 11 toward the tip of the piezoelectric sheet 11 and along the piezoelectric sheet 11, and in front of the tip surface of the piezoelectric sheet 11. After being bent, it is bonded to the wind receiving fin 13 at the other end.

Only one end of one piece 12 </ b> A formed by bending the hinge 12 is bonded to the tip of the piezoelectric sheet 11. Between the bonded portion 21 and the bent portion 22, it is disposed along the piezoelectric sheet 11, but is not bonded to the piezoelectric sheet 11. The other piece 12 </ b> B formed by bending the hinge 12 is bonded to the wind-receiving fin 13 only by an adhesive portion 23. Between the bonded portion 23 and the bent portion 22, it is disposed along the wind receiving fin 13, but is not bonded to the wind receiving fin 13. Therefore, the hinge 12 is connected to the piezoelectric sheet 11 only in a part, and the adhesive portion 21 and the bent portion 22 are offset in the long side direction of the piezoelectric sheet 11. Further, the hinge 12 is connected to the wind vane fin 13 only in a part, and the adhesive portion 23 and the bent portion 22 are offset in the short side direction of the wind vane fin 13.

  For this reason, as shown in FIG. 3B, the hinge 12 is not only moved in the bending (opening / closing) direction as shown by the arrow A1 with the bending portion 22 as the center, but also shown by an example in the arrow A2 and the arrow A3. It can also be moved in the direction of twisting the thin plate-like member of the hinge 12. Accordingly, as shown in FIGS. 1 and 2, the wind-receiving fin 13 also has a high degree of freedom, not only in the bending direction (A1) of the hinge 12, but also in the directions exemplified by the arrows A2 and A3. It is connected to the piezoelectric sheet 11 so as to be movable.

  Here, the bending direction indicated by arrow A1 refers to the direction of movement in which the two adhesive portions 21 and 23 of the hinge 12 approach or separate from each other with the bending portion 22 as a base point. The direction indicated by the arrow A2 is, for example, a direction in which the wind receiving fin 13 rotates in the plane. The direction indicated by the arrow A3 is, for example, a direction in which the wind-receiving fin 13 is inclined about the axis.

  Such a hinge 12 is manufactured using, for example, a resin such as natural rubber, silicone rubber, or urethane rubber, or a metallic thin plate such as aluminum or stainless steel.

  The wind receiving fins 13 have an elongated rectangular shape, and the long sides of the wind receiving fins 13 are arranged in a direction substantially orthogonal to the long side direction of the piezoelectric sheet 11. The long side of the wind receiving fin 13 is larger than the short side (width) of the piezoelectric sheet 11. Therefore, both side portions of the wind receiving fin 13 extend beyond the side surface of the piezoelectric sheet 11.

  Further, as shown in FIGS. 1 and 2, the bonding portion 23 between the wind vane fin 13 and the hinge 12 is provided at a position offset from the midpoint in the short side direction of the wind vane fin 13 to the tip side. For this reason, the distance D1 from the midpoint of the bonding portion 23 to the tip of the wind fin 13 is shorter than the distance D2 from the midpoint of the bonding portion 23 to the opposite end surface of the wind fin 13. That is, the area S1 of the region R1 on the distal end side from the middle point of the bonding portion 23 is smaller than the area S2 of the region R2 on the proximal side of the middle point of the bonding portion 23. Such wind receiving fins 13 are manufactured using a material having a predetermined rigidity with respect to the wind, for example, a resin sheet or paper, and are laminated with a resin such as plastic as necessary.

Next, the operation of the structural health monitoring system 1 will be described.
First, the power generation mechanism of the power generation element 6 will be described. The power generating element 6 fixes the fixed end 10 to the structure when the structural health monitoring system 1 is installed. At this time, the direction of the power generating element 6 is adjusted so that the wind receiving fins 13 are arranged on the windward side of the assumed air flow. For this reason, the electric power generating element 6 is disposed on the leeward side on the proximal end side and on the windward side on the distal end side.

  Hereinafter, a mechanism in which the piezoelectric sheet 11 of the power generating element 6 vibrates due to an air flow will be described mainly with reference to FIGS. 4 to 7. In each figure, the airflow flows from left to right as indicated by arrow W1. That is, the windward side is the front end side of the piezoelectric sheet 11 and the fixed end 10 is the leeward side. Moreover, the arrow displayed superimposed on the wind receiving fin 13 schematically indicates the force that the wind receiving fin 13 receives from the air flow.

First, as shown in FIG. 4, it is assumed that the wind blows in the assumed direction and the wind receiving fins 13 are inclined. At this time, in the wind receiving fin 13, the region R 1 on the tip (windward) side from the bonding portion 23 is above the bonding portion 23, and the region R 2 on the base end (leeward) side from the bonding portion 23 is below the bonding portion 23. Is arranged. Therefore, in this state, the wind receiving fin 13 receives the air flow at the lower surface 13B, and the air flow acts to push up the wind receiving fin 13. Along with this, the piezoelectric sheet 11 connected to the wind receiving fins 13 is deformed so that the tip portion rises. Since the base end portion of the piezoelectric sheet 11 is fixed to the fixed end 10, a current corresponding to the deformation amount and the deformation direction of the distal end portion is generated in the piezoelectric sheet 11. The current generated at this time is input to the charging circuit 5.

  Here, since the wind receiving fin 13 is connected to the hinge 12 at a position offset from the center to the windward side, the tip (windward) side region R1 and the base end (leeward) side region R2 The magnitude of the force received from the airflow varies depending on the ratio of the areas S1 and S2 of the respective regions. Specifically, since the area S2 of the proximal end region R2 is larger than the area S1 of the distal end region R1, the force received from the air flow is also larger in the proximal end region R2.

  As described above, the power generating element 6 is configured such that the force received by the wind receiving fins 13 from the airflow is mainly unbalanced between the windward side and the leeward side. Can be changed. That is, the proximal end region R2 that receives more force is pushed upward relative to the distal end region R1, but the wind receiving fins 13 are connected to the piezoelectric sheet 11 via the hinges 12. Therefore, the region R2 rotates in a direction that is relatively lifted with respect to the region R1, with the adhesive portion 23 of the hinge 12 as a fulcrum. Along with this, the region R1 on the front end side of the wind receiving fin 13 is lowered. For this reason, the wind-receiving fin 13 approaches a posture substantially parallel to the air flow.

  As shown in FIG. 5, when the wind receiving fin 13 approaches a posture substantially parallel to the air flow, the force received by the wind receiving fin 13 from the wind becomes small. Accordingly, since the force to bend the piezoelectric sheet 11 is weakened, the wind-receiving fin 13 is returned to the original position by the repulsive force of the piezoelectric sheet 11. Then, as the deformation amount of the piezoelectric sheet 11 decreases, the power generation amount of the piezoelectric sheet 11 decreases.

  Further, when the wind receiving fin 13 approaches a posture substantially parallel to the airflow, the wind force received in each of the distal end region R1 and the proximal end region R2 is reduced. Along with this, the difference in wind force received by the two region differences R1, R2 also becomes smaller. However, since the force received from the wind is relatively large on the region R2 side where the area is large, the wind receiving fin 13 continues to be pushed up in the region R2 on the downstream side. That is, the force received by the wind receiving fin 13 from the wind is reduced, and the piezoelectric sheet 11 is hardly deformed. However, the wind receiving fin 13 connected to the piezoelectric sheet 11 via the hinge 12 has a downstream region R2. It is pushed up relatively.

  When the region R2 on the downstream side of the wind receiving fin 13 is pushed upward beyond a position substantially parallel to the wind, the wind receiving fin 13 receives an air flow on the upper surface 13A. As a result, as shown in FIG. 6, the wind receiving fins 13 start to move in the direction of pushing down the tip portion of the piezoelectric sheet 11. When the inclination angle of the wind receiving fin 13 is increased, the force received by the wind receiving fin 13 from the wind is increased, and the wind receiving fin 13 is pushed down as a whole. Along with this, the piezoelectric sheet 11 connected to the wind receiving fin 13 via the hinge 12 is bent downward with the tip portion as the center, and the piezoelectric sheet 11 generates electricity. As the wind receiving fins 13 are pushed downward, the piezoelectric sheet 11 is greatly deformed and the amount of power generation is increased. Since the change direction of the piezoelectric sheet 11 is the opposite direction of FIG. 4, the polarity of the voltage formed by power generation is opposite.

  Further, in the wind receiving fin 13, the downstream region R <b> 2 that receives more force is pushed down from the region R <b> 1. Since the wind-receiving fin 13 is connected to the piezoelectric sheet 11 via the hinge 12, the region R1 rotates in a direction in which the region R1 is lifted relative to the region R2 with the adhesive portion 23 of the hinge 12 as a fulcrum. As a result, the wind receiving fins 13 are rotated so as to be in a posture substantially parallel to the air flow.

  As shown in FIG. 7, when the wind receiving fins 13 are rotated and the inclination angle is reduced, the force received by the wind receiving fins 13 from the air flow is reduced, so that the force for deforming the piezoelectric sheet 11 is also reduced. As a result, the piezoelectric sheet 11 is restored by the repulsive force and returned to its original state. Since the deformation amount of the piezoelectric sheet 11 is small, the power generation amount is small.

  In this state, when the region R1 on the upstream side of the wind receiving fin 13 is again pushed up beyond a position substantially parallel to the air flow, the wind receiving fin 13 receives the air flow on the lower surface 13B. Thereafter, the wind receiving fins 13 are pushed up to the posture shown in FIG.

  By repeating the above operation, the piezoelectric sheet 11 vibrates and can continuously generate power. As described with reference to FIGS. 4 to 7, in the power generating element 6, the balance of the wind receiving fins 13 is easily changed by shifting the connecting position of the hinges 12 from the center of the wind receiving fins 13. . Furthermore, since the windshield fin 13 and the piezoelectric sheet 11 are connected with high flexibility, the hinge 12 can be moved not only in the vertical vibration but also in the twist direction. The wind received by the receiving fins 13 can be easily escaped. From these things, the electric power generation element 6 can vibrate the front-end | tip part easily and reliably. Therefore, even if the air flow is almost constant, the wind receiving fins 13 and the piezoelectric sheet 11 can be continuously vibrated, and stable power generation can be expected.

Here, the maximum value of the voltage generated by the power generation element 6 is generated when the deformation amount of the piezoelectric sheet 11 becomes the largest.
FIG. 8 shows an example of a voltage waveform output from the power generation element 6. The horizontal axis shows the passage of time, and the vertical axis shows the output voltage. Line L1 shows the output waveform of the power generation element 6 in the embodiment. As described with reference to FIGS. 4 to 7, when the piezoelectric sheet 11 vibrates, the power generation element 6 outputs a voltage that fluctuates periodically in a range of about ± 2V. In the voltage waveform shown in the line L1, the upper peak value is output when the wind-receiving fin 13 is pushed up most by the air flow, that is, when the deformation amount of the piezoelectric sheet 11 is maximized upward. The lower peak value is output when the wind-receiving fin 13 is pushed down most by the air flow, that is, when the deformation amount of the piezoelectric sheet 11 is maximized downward. Here, the magnitude of the output voltage value is an amount depending on the area of the piezoelectric sheet 11 and the like.

  On the other hand, as a comparative example, as shown in FIG. 9, the power generation characteristics of the power generation element 41 in which the wind receiving fins 13 are fixed to the piezoelectric sheet 11 were examined. Here, in the power generation element 41, the wind receiving fin 13 is fixed to the piezoelectric sheet 11 by two fixing portions 42 and 43. The fixing portion 42 is formed on the downstream side of the wind receiving fin 13, and the fixing portion 43 is formed on the upstream side from the midpoint. Therefore, in the power generating element 41, the wind receiving fins 13 and the piezoelectric sheet 11 vibrate substantially integrally, and a voltage is generated with the vibration of the piezoelectric sheet 11.

  As shown by the line L2 in FIG. 8, the output voltage value of the power generation element 41 of the comparative example was about ± 0.5V. This is because the wind receiving fins 13 are fixed to the piezoelectric sheet 11, so that the wind force received by the wind receiving fins 13 cannot be released and the piezoelectric sheet 11 is easily bent in one direction. it is conceivable that. Further, in the power generation element 41 of the comparative example, the vibration width of the piezoelectric sheet 5 due to the air flow is small, and vibration cannot be generated efficiently unless there is a change in wind force, so that only a small output voltage can be obtained. As described above with reference to the comparative example, the power generating element 6 of this embodiment can obtain larger vibration energy even in the case of constant wind power.

Here, the voltage generated in the power generation element 6 as shown by the line L1 in FIG. 8 is input to the charging circuit 5 shown in FIG. In the charging circuit 5, the current generated by the voltage generated by the power generation element 6 is rectified by the rectifier circuit 15, and the electric charge generated at this time is stored in the capacitor 16. An example of a voltage waveform generated by the charging circuit 5 is shown in FIG. The horizontal axis of FIG. 10 shows the passage of time, and the vertical axis shows the voltage. The upper part of FIG. 10 shows the change over time of the amount of charge accumulated in the capacitor 16. Further, the lower part shows the charge charged in the battery 3. As shown in the upper part of FIG. 10, charges are accumulated in the capacitor 16 over time. When the accumulated charge amount reaches a certain amount, a predetermined voltage is output by the DC / DC converter 17 as shown in the lower part of FIG.

  The deformation of the piezoelectric sheet 11 mainly occurs when the position of the wind receiving fins 13 is changed by the air flow. Since the wind-receiving fin 13 can move not only in the opening / closing direction of the hinge 12 but also in other directions, the vibration of the wind-receiving fin 13 and the piezoelectric sheet 11 may not be periodic. Even in this case, the piezoelectric sheet 11 continuously vibrates, so that power generation is continuously performed.

  In the inspection of the structure using the structural health monitoring system 1 according to this embodiment, the sensor 2 uses the power of the battery 3 to acquire the data that detects the state of the structure. The acquired data is transmitted to an analysis device (not shown) and analyzed. For example, when the sensor 2 is an acceleration sensor, data is transmitted to the analysis device when the sensor 2 detects acceleration. The analysis device determines a building abnormality based on the acquired data. In the type in which the sensor 2 operates intermittently, the sensor 2 is driven by receiving power supply from the battery 3, and the acquired data is transmitted to the analysis device. In any case, the charge amount of the battery 3 decreases with the operation of the sensor 2, but is charged at any time by the power generation device 4.

  For example, as shown in FIG. 11, when the power generating element 6 is attached to a beam 44 of a structure such as a bridge over a river or a harbor, the wind receiving fins 13 vibrate due to the wind blowing toward the beam 44. . Along with this, the piezoelectric seed 11 generates power. For example, when an acceleration sensor (not shown) is attached to the beam 44 as the sensor 2, vibration of the beam 44 or a bridge including the beam 44 can be detected. Since electric power is stored in the battery 3 by the power generation element 6, vibration of the beam 44 and the bridge can be monitored while greatly suppressing the replacement frequency of the battery 3. Further, when an ultrasonic sensor (not shown) is attached to the beam 44, such a change can be detected when the beam 44 is cracked. Even when the generated power of the power generation element 6 is small, sufficient power can be supplied when the sensor is operated intermittently.

  As described above, in this embodiment, the wind receiving fins 13 of the power generating element 6 are arranged on the upstream side of the air flow, and the piezoelectric sheet 11 is offset from the center of the wind receiving fins 13 to the upstream side. Connected. As a result, it is possible to vary the force received by the wind receiving fins 13 from the air flow between the upstream side and the downstream side with respect to the connecting position with the hinge 12, so that the balance of the wind receiving fins 13 is changed. It becomes easy to let. For this reason, even when the air flow is almost constant, the position of the wind receiving fins 13 can be easily changed. Since the vibration of the piezoelectric sheet 11 is caused by the change in the position of the wind receiving fins 13, the piezoelectric sheet 11 is easily vibrated, and the piezoelectric sheet 11 can continuously generate power. Furthermore, since the vibration of the piezoelectric sheet 11 can be increased, the power generation amount can be increased.

Further, in this embodiment, the piezoelectric sheet 11 and the wind-receiving fin 13 are connected to the flexible hinge 12. Since the flexible hinge 12 has a high degree of freedom to allow movement in the twist direction in addition to the bending direction, the piezoelectric sheet 11 and the wind vane fin 13 can be connected. It is easy to change in response to. This makes it possible to generate power more reliably and stably. Further, since the positions of the bonding portions 21 and 23 of the hinge 12 and the bent portion 22 are offset in the air flow direction, the in-plane rotation and inclination of the wind receiving fin 12 are facilitated. This is also a factor that makes the piezoelectric sheet 11 easy to vibrate. For these reasons, the piezoelectric element 6 of this embodiment can realize stable power generation and efficient power generation.

  Further, since the monitoring system of this embodiment can be operated while charging the battery 3 as appropriate, the environment and the structure can be monitored for a long time. Since the replacement frequency of the battery 3 can be reduced, the environment and structures can be managed efficiently.

  Here, another application example of the monitoring system will be described. The monitoring system 45 shown in FIG. 12 is constructed as an indoor industrial device, for example, a sensor system for the cooling fan 46. The sensor 2 is, for example, a power monitor for the cooling fan 46. The power generating element 6 is provided in the vicinity of the outlet of the cooling fan 46, the fixed end 10 is disposed on the leeward side, and the wind receiving fins 13 are disposed on the windward side.

  In the monitoring system 45, the operation of the industrial device can be monitored while charging the battery 3 by power generation using the wind generated by the industrial device. Since the piezoelectric sheet 11 continuously vibrates while the cooling fan 46 is in operation, the power generation element 6 can stably generate power. Industrial equipment is not limited to the cooling fine 46. The sensor 2 may monitor devices other than the cooling fan 46.

Moreover, the monitoring system 47 shown in FIG. 13 is constructed so as to generate power using wind from the indoor air conditioning fan 48. The sensor 2 may be a sensor that monitors the operation of the air conditioning fan 48 or may be a sensor that detects the state of the building in which the air conditioning fan 48 is installed. Moreover, the sensor used for the other apparatus installed in the building may be used. The power generating element 6 is provided in the vicinity of the air outlet of the air conditioning fan 48, and the fixed end 10 is disposed on the leeward side and the wind receiving fins 13 are disposed on the windward side.
The environment monitoring system 47 can monitor the operation of a building or the like while charging the battery 3 by power generation using wind output from the air conditioning fan 48. Since the piezoelectric sheet 11 continuously vibrates while the air conditioning fan 48 is in operation, the power generating element 6 can generate power stably.

Further, the connecting member of the power generation element 6 is not limited to the hinge 12. Moreover, the modification in the case of using a hinge for a connection member is demonstrated below.
In the hinge 51 shown in a developed view in FIG. 14, the width of the central portion of the thin plate member is reduced by the notch 52. The notches 52 are triangular on both sides. By reducing the width of the bent central portion, the degree of freedom of connection of the wind-receiving fins 13 to the piezoelectric sheet 11 can be further increased. As a result, the piezoelectric sheet 11 becomes easier to vibrate, and the power generation amount increases. The curved shape of the notch 52 may be used.

  Further, in the hinge 61 shown in a developed view in FIG. 15, the width of the central portion of the thin plate-like member is reduced by a rectangular notch 62. The notches 62 are formed on both sides, respectively, and the degree of freedom of connection of the wind-receiving fins 13 to the piezoelectric sheet 11 can be further increased by reducing the width of the central portion. As a result, the piezoelectric sheet 11 becomes easier to vibrate, and the power generation amount increases.

  The hinge 71 shown in a developed view in FIG. 16 has a rectangular opening 72 formed at the center of the thin plate member, thereby reducing the width of the bent portion 22. Thereby, the freedom degree of the connection of the wind-receiving fin 13 with respect to the piezoelectric sheet 11 can further be increased. As a result, the piezoelectric sheet 11 becomes easier to vibrate, and the power generation amount increases.

All examples and conditional expressions given here are intended to help the reader understand the inventions and concepts that have contributed to the promotion of technology, and such examples and It is to be construed without being limited to the conditions, and the organization of such examples in the specification is not related to showing the superiority or inferiority of the present invention. While embodiments of the present invention have been described in detail, various changes, substitutions and variations can be made thereto without departing from the spirit and scope of the present invention.

The features of the above embodiment will be added below.
(Appendix 1)
A piezoelectric sheet having a deformable piezoelectric material, the base end of which is fixed, a fin connected to the tip portion of the piezoelectric sheet and receiving wind, and the fin being offset from the center to the tip side, A power generation element comprising: a fin and a connecting member for connecting the piezoelectric sheet.
(Additional remark 2) The electric power generation element of Additional remark 1 characterized by the front-end | tip part of the said piezoelectric sheet being arrange | positioned toward the windward.
(Supplementary Note 3) The power generating element according to Supplementary Note 1 or Supplementary Note 2, wherein the fin has a larger area on the distal end side than the coupling position and on a proximal side relative to the coupling position.
(Supplementary Note 4) The fin is connected to the piezoelectric sheet via the connecting member formed by bending a plate-like member, and the connecting member has one end fixed to the piezoelectric sheet and the other end is connected to the piezoelectric sheet. It is fixed to the fin, and is bent and formed so as to protrude toward the tip side from one end to the other end. Power generation element.
(Additional remark 5) The power generation element of Additional remark 4 characterized by the width | variety of the said connection member being reduced compared with the others.
(Additional remark 6) It contains the said electric power generation element as described in any one of additional remark 1 thru | or additional notes 4, the battery which accumulate | stores the electric power output from the said electric power generation element, and the sensor which receives the electric power supply from the said battery. Monitoring system.

1 Structural health monitoring system (monitoring system)
2 Sensor 3 Battery 6 Power generation element 11 Piezoelectric sheet 12, 51, 61, 71 Hinge (connection member)
13 Wind receiving fins 45, 47 Monitoring system R1 Upwind area R2 Downwind area S1 Upwind area S2 Downwind area

Claims (6)

A piezoelectric sheet having a deformable piezoelectric material and having a proximal end fixed;
A fin connected to the tip of the piezoelectric sheet and receiving wind;
A connecting member that is attached to the tip portion of the piezoelectric sheet and connects the piezoelectric sheet and a portion disposed on the tip portion side of the piezoelectric sheet from the center of the fin;
A power generating element comprising:   The power generation element according to claim 1, wherein a tip end portion of the piezoelectric sheet is disposed toward the windward side. The area of the portion of the fin disposed on the proximal end side of the piezoelectric sheet from the coupling position with the piezoelectric sheet via the coupling member is the portion of the fin disposed on the distal end side of the piezoelectric sheet from the coupling position. The power generation element according to claim 1, wherein the power generation element is larger than an area . The connecting member is
One end bonded to the tip of the piezoelectric sheet;
The other end bonded to the fin;
A bent portion that is provided between the one end portion and the other end portion, and is disposed on the front end side of the adhesive portion between the piezoelectric sheet and the one end portion;
The power generation element according to any one of claims 1 to 3, wherein the power generation element is provided. The piezoelectric sheet has a strip shape, and is connected to the connecting member at the tip of the strip-shaped piezoelectric sheet,
5. The fin according to claim 1, wherein the fin has an elongated rectangular shape, and the long side of the fin is arranged in a direction substantially orthogonal to the long side direction of the piezoelectric sheet. The power generating element according to one item. The power generating element according to any one of claims 1 to 5,
A battery for storing electric power output from the power generation element;
A sensor that receives power from the battery;
A monitoring system characterized by including:

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