Power generation module, environmental sensor, and current sensor
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Filing Date
- 2026-03-25
- Publication Date
- 2026-06-29
Abstract
Description
Power generation modules, power generation devices, environmental sensors, and current sensors
[0001] The present disclosure relates to a power generation module, a power generation device, an environmental sensor, and a current sensor.
[0002] A device has been proposed that includes an amorphous wire whose internal magnetic field changes in response to changes in the magnetic field generated by the current flowing through the wire, and a detection coil wound around the amorphous wire (see, for example, Patent Document 1). This device converts changes in the current flowing through the wire into voltage through electromagnetic induction.
[0003] JP 2003-315376 A International Publication No. 2023 / 079838
[0004] However, the above-described conventional device has a problem in that the induction efficiency of the magnetic field generated by the current flowing through the electric wire is low.
[0005] The present disclosure aims to provide a power generation module and a power generation device that can improve performance by increasing the induction efficiency of the magnetic field generated by the current flowing through the electric wire, an environmental sensor that receives power from the power generation device, and a current sensor with high detection sensitivity.
[0006] The power generation module of the present disclosure has one or more power generation element units, each of which has a magnetic body and a coil wound around the magnetic body, one end of the magnetic body being a first magnetic collection surface and the other end of the magnetic body being a second magnetic collection surface, and when the magnetic body is in the vicinity of an electric wire through which an alternating current flows, magnetic lines of force generated by the current penetrate the first magnetic collection surface, the magnetic body, and the second magnetic collection surface, generating a voltage in the coil.
[0007] The power generation device of the present disclosure is characterized by having the above-mentioned power generation module, one or more rectifiers that rectify the voltages generated in the coils of the one or more power generation element units, a storage unit that stores the power output from the rectifiers, another rectifier that rectifies the voltages generated in the coils of the power generation module, and a storage unit that stores the power output from the rectifiers.
[0008] The environmental sensor disclosed herein is a sensor that receives power stored in the storage unit of the above-mentioned power generation device, and is characterized by having a sensor unit that senses the environment or condition, a wireless transmitter that transmits information sensed by the sensor unit, and a switching unit that switches between an on state in which the power stored in the storage unit is supplied to the wireless transmitter and an off state in which the power is not supplied to the wireless transmitter.
[0009] The current sensor of the present disclosure includes one or more power generation element units and a processing unit, each of which includes a magnetic body and a coil wound around the magnetic body, one end of the magnetic body being a first magnetic collecting surface and the other end of the magnetic body being a second magnetic collecting surface, and when the magnetic body is near an electric wire through which an alternating current flows, magnetic field lines generated by the current penetrate the first magnetic collecting surface, the magnetic body, and the second magnetic collecting surface, generating a voltage in the coil, and the processing unit calculating and outputting the current flowing in the electric wire based on the voltage generated in the coil of the one or more power generation element units.
[0010] The power generation module or power generation device of the present disclosure can achieve high power generation efficiency. The environmental sensor of the present disclosure can wirelessly transmit information sensed by the sensor unit using power stored in the power storage unit of the power generation device. The current sensor of the present disclosure can achieve high detection sensitivity.
[0011] 1 is a perspective view (including an enlarged view of a power generating element unit) that schematically illustrates the structure of a power generating module according to a first embodiment; FIG. 2 is a view (part 1) showing magnetic field lines penetrating the power generating element unit; FIG. 3 is a view (part 2) showing magnetic field lines penetrating the power generating element unit; FIG. 4 is a perspective view that schematically illustrates the structure of a power generating module (including two power generating element units) according to a first embodiment; FIG. 5 is a block diagram illustrating the configuration of a power generating device and an environmental sensor that includes a power generating module according to a first embodiment; FIG. 6 is a diagram illustrating an induced voltage waveform (dashed line) when an iron core is used as the magnetic body, and an induced voltage waveform (solid line) when a composite magnetic wire that generates the large Barkhausen effect is used as the magnetic body; FIG. 7 is a diagram illustrating voltage waveforms (induced voltage and voltage due to the large Barkhausen effect) that are generated when a composite magnetic wire and a magnetic collector (iron core) are used as the magnetic body; and FIG. 8 is a diagram illustrating the relationship between the magnetic field applied to the power generating element unit and the generated power. (A) and (B) are a perspective view and a side view that schematically illustrate the configuration of a power generating element unit; and (A) and (B) are a perspective view and a side view that schematically illustrate the configuration of another power generating element unit. 10 is a block diagram schematically showing a configuration of a sensor unit of a current sensor according to a second embodiment;FIG. 11 is a block diagram schematically showing a configuration of a modification of the current sensor according to the second embodiment;FIG.
[0012] A power generation module according to an embodiment, a power generation device including the power generation module, an environmental sensor that receives power from the power generation device, and a current sensor that includes a power generation element of the power generation module will be described below with reference to the drawings. The following embodiments are merely examples, and the embodiments can be combined and modified as appropriate. The figures show coordinate axes of an XY Cartesian coordinate system to facilitate understanding of the relationships between the figures. In addition, in the figures, components having the same or similar functions are designated by the same reference numerals.
[0013] First Embodiment FIG. 1 is a perspective view (including an enlarged view of a power generating element unit) that schematically illustrates the structure of a power generating module 10 according to a first embodiment. As illustrated in FIG. 1 , the power generating module 10 is attached to an electric wire 200 through which AC current flows, such as an electric wire in a switchboard or a motor power line. The power generating module 10 generates power using a leakage magnetic field from the electric wire 200. The power generating module 10 can also detect the current flowing through the electric wire 200 using the leakage magnetic field from the electric wire 200. The power generating element unit 100 of the power generating module 10 is attached to the electric wire 200 using a holding unit 150 (e.g., a dedicated jig, clamp, etc.). There are no limitations on the structure of the holding unit 150, but it is preferable that the holding unit 150 be made of a material that does not affect the magnetic field. Furthermore, if an operator holds the power generating element unit 100 of the power generating module 10 by hand, the holding unit 150 is not necessary.
[0014] The power generation module 10 has one or more power generation element units 100. Each power generation element unit 100 has a magnetic body 110 and a coil 120 wound around the magnetic body 110. One end of the magnetic body 110 is a first magnetic field collecting surface 110a, and the other end of the magnetic body 110 is a second magnetic field collecting surface 110b. When the magnetic body 110 is near an electric wire 200 through which an alternating current flows, magnetic field lines M generated by the current penetrate the first magnetic field collecting surface 110a, the magnetic body 110, and the second magnetic field collecting surface 110b, generating a voltage in the coil 120. The first magnetic field collecting surface 110a and the second magnetic field collecting surface 110b are flat surfaces, but may also be curved surfaces.
[0015] Conventional current sensors, such as current transformer (CT) type sensors, require an annular magnetic core to be positioned so as to completely surround the current line (i.e., surround the entire circumference), making them difficult to attach to the current line. This is because the current line must be passed through the hole in the annular magnetic core beforehand, making it difficult to attach the magnetic core later.
[0016] The current sensor of Patent Document 1 uses a rod-shaped magnetic core instead of a ring-shaped magnetic core, making it easy to attach to a current line, but like the CT method, it detects current by utilizing current generated by electromagnetic induction.
[0017] In the CT-type current sensor and the current sensor of Patent Document 1, the outer diameter of the magnetic core is the same as or smaller than the inner diameter of the coil. In contrast, in the power generation module, power generation device, environmental sensor, and current sensor according to this embodiment, a magnetic collector larger than the inner diameter of the coil 120 (i.e., the radial size of the coil 120 is larger than the inner diameter of the coil 120) is provided on the outside of each end of the coil 120. This allows the magnetic collector surface to have a larger area, which can induce leakage magnetic fields (magnetic lines of force) from the current lines to the magnetic core, thereby increasing the current generated in the coil 120 by electromagnetic induction (or the generated power obtained from the coil 120).
[0018] Furthermore, in the power generating element of Patent Document 2, ferrite beads are provided on both ends of the magnetic wire, but the magnetic poles of the magnets are positioned at positions offset in a direction perpendicular to the longitudinal direction of the wire. In other words, in the power generating element of Patent Document 2, the magnetic poles of the magnets are not positioned on an imaginary line overlapping the magnetic wire, but are positioned at positions offset in a direction perpendicular to this imaginary line.
[0019] As described above, in both Patent Documents 1 and 2, only a portion of the magnetic field lines generated from the current line or magnet are induced into the magnetic core, which poses the problem of poor efficiency in guiding the magnetic field lines generated from the current line or magnet into the magnetic core.
[0020] The Large Barkhausen effect occurs when a magnetization reversal occurs above a certain threshold value of the magnetic field, and so the Large Barkhausen effect occurs as long as that threshold value is reached. The power generating element of Patent Document 2 does not intend to induce magnetic field lines above the threshold value of the magnetic field that can cause the Large Barkhausen effect.
[0021] In this embodiment, not only is the magnetization reversal operation of the large Barkhausen effect utilized, but the magnetic core is also utilized as an electromagnetic induction core, so that the current generated by the magnetization reversal operation of the large Barkhausen effect and the current of the electromagnetic induction component obtained by inducing as many magnetic lines of force as possible generated from the current line into the magnetic core can be utilized for power generation, thereby increasing the amount of power generation.
[0022] The power generating element unit 100 is held so that a direction parallel to a straight line C connecting the center of the first magnetic field collecting surface 110a and the center of the second magnetic field collecting surface 110b intersects with the direction (Y direction) in which the electric wire 200 extends. It is desirable that the straight line C be perpendicular to the direction (Y) in which the electric wire 200 extends.
[0023] The magnetic body 110 has a magnetic core 111 (also called a "composite magnetic wire" or "Wiegand wire") that generates a large Barkhausen effect in response to a change in magnetic flux, and magnetic collectors 112 that are soft magnetic materials that surround the outer periphery of the magnetic core 111. The magnetic collectors 112 are respectively arranged at the ends of the magnetic core 111 (for example, so as to surround the vicinity of each of both ends). The magnetic body 110 may be integrally formed from a soft magnetic material. However, it is more desirable for the magnetic body 110 to have a structure that includes the magnetic core 111 that generates a large Barkhausen effect in response to a change in magnetic flux, and the magnetic collectors 112 that are soft magnetic materials that surround the outer periphery of the magnetic core 111. The soft magnetic material may be a steel material such as SS400 (a rolled steel material for general structures specified in JIS G3101) or S45C (a carbon steel material for machine structures specified in JIS G4051), a magnetic stainless steel material such as SUS430 or SUS440 (a hot-rolled stainless steel plate specified in JIS G4304), or a high-magnetic-permeability material such as permalloy or permendur.
[0024] 2 and 3 are diagrams (part 1 and part 2) showing magnetic field lines M that are generated by AC current flowing through the electric wire 200 and that penetrate the power generating element unit 100. Fig. 2 shows the magnetic field lines M when current flows from the front of the paper on which Fig. 2 is drawn to the back. Fig. 3 shows the magnetic field lines M when current flows from the back of the paper on which Fig. 3 is drawn to the front. The power generating element unit 100 is desirably arranged so that the first magnetic field collecting surface 110a and the second magnetic field collecting surface 110b are perpendicular to the annular magnetic field lines M that are generated around the electric wire 200. In this case, the magnetic field lines M are efficiently collected in the magnetic core 111 via the magnetic field collecting body (soft magnetic body) 112, resulting in improved power generation efficiency.
[0025] FIG. 4 is a perspective view schematically illustrating the structure of the power generation module 10 (including the power generation element units 100, 100a) according to the first embodiment. As shown in FIG. 4, the power generation module 10 includes multiple power generation element units 100, 100a attached to the same electric wire 200. The power generation element units 100, 100a have the same structure. However, the power generation element units 100, 100a may have different structures. The power generation element units 100, 100a may be arranged on opposite sides of the electric wire 200. The power generation element unit 100a of the power generation module 10 is attached to the electric wire 200 using a holding unit 150a (e.g., a dedicated jig, clamp, etc.). There are no limitations on the structure of the holding unit 150a, but it is preferable that the holding unit 150a be made of a material that does not affect magnetic fields. If the operator holds the power generation element unit 100a by hand, the holding unit 150a is not necessary.
[0026] FIG. 5 is a block diagram showing the configuration of a power generation device 50 including a power generation module 10 according to the first embodiment, and an environmental sensor 58. The power generation module 10 includes power generation element units 100, 100a, and generates a voltage in a coil 120 by an AC current flowing through an electric wire 200. The voltage generated in the coil 120 (i.e., a power generation pulse) exhibits a positive and negative pulse shape, and is full-wave rectified by rectifiers 51, 51a including a rectifier circuit. The rectifiers 51, 51a are provided for each of the power generation element units 100, 100a constituting the power generation module 10. Therefore, when the power generation module 10 includes multiple power generation element units 100, 100a, multiple rectifiers 51, 51a are provided corresponding to the multiple power generation element units 100, 100a, respectively. The rectifiers 51, 51a may include a half-wave rectifier circuit rather than a full-wave rectifier circuit.
[0027] The voltage rectified by the one or more rectifiers 51, 51a (i.e., the power of the power generation pulses output from the one or more rectifiers 51, 51a) is stored in the power storage unit 52. The power storage unit 52 is a rechargeable secondary battery, a capacitor, or the like.
[0028] The environmental sensor 58 receives the power stored in the power storage unit 52 of the power generation device 50. The environmental sensor 58 includes, for example, a sensor unit 55 that senses the state of a machine tool, which is an example of a monitored object, or the environment around the machine tool (i.e., the state), a wireless transmitter unit 56 that transmits information sensed by the sensor unit 55 to a control device 57 of the machine tool, and a switching unit 53 that switches between an ON state in which the power stored in the power storage unit 52 of the power generation device 50 is supplied to the wireless transmitter unit 56 and an OFF state in which power is not supplied to the wireless transmitter unit 56. The environmental sensor 58 also includes a voltage monitoring unit 54 that monitors the internal voltage of the power storage unit 52 and switches the switching unit 53 to the ON state when the internal voltage exceeds the minimum drive voltage required for operation of the wireless transmitter unit 56. Note that although the power generation device 50 and the environmental sensor 58 are described as separate devices in FIG. 5 , the power generation device 50 may be part of the environmental sensor 58 (e.g., a system including the environmental sensor 58). The control device 57 can control the operation of the machine tool (such as emergency stop, issuing an alarm, and recording the sensing information) based on the sensing information received from the environmental sensor 58. In addition, the sensor unit 55 can be supplied with power stored in the power storage unit 52.
[0029] When the environmental sensor 58 is installed in a switchboard or a motor in a factory, the environmental sensor 58 senses the temperature, humidity, acceleration, current, magnetic field, CO ２ When the environmental sensor 58 is attached to an outdoor electric wire, the objects of sensing by the environmental sensor 58 include temperature, humidity, wind speed, wind direction, amount of precipitation, magnetic field, CO ２ concentration, pH of water and soil, water level, soil moisture content, slope, acceleration (impact), or solar radiation (on cloudy days).
[0030] If the power generated by the power generation module 10 is directly sent to the sensor unit 55 and wireless transmitter 56 via the power storage unit 52, natural discharge occurs when power is not being generated, causing the internal voltage of the power storage unit 52 to drop rapidly. By providing the voltage monitoring unit 54 and the switching unit 53, the switch is kept in an off state until the voltage required for the operation of the sensor unit 55 and wireless transmitter 56 is accumulated. This type of control allows for efficient charging without losing charge.
[0031] 6 shows the waveform of the induced voltage when only an iron core is used as the magnetic body 110 of the power generating element unit 100 (dashed line), and the waveform of the induced voltage when only a composite magnetic wire that generates the Large Barkhausen effect is used as the magnetic body (solid line). The waveform of the induced voltage (dashed line) generated in a coil wound around a magnetic body consisting only of an iron core without the Large Barkhausen effect has a wide pulse width and a large amount of generated charge, but a low peak voltage of about 5 V. On the other hand, the waveform of the induced voltage (solid line) generated in a coil wound around a magnetic body consisting only of a composite magnetic wire that generates the Large Barkhausen effect has a narrow pulse width of 80 μs or less and a small amount of generated charge, but a high peak voltage of 15 V to 20 V.
[0032] FIG. 7 shows the waveform of an induced voltage when the magnetic body 110 includes a composite magnetic wire as the magnetic core 111 and a soft magnetic body as the magnetic collector (iron core). FIG. 7 shows the waveform of the voltage generated in the coil 120 by the voltage due to electromagnetic induction (dashed line in FIG. 6 ) and the voltage due to the large Barkhausen effect (solid line in FIG. 6 ) in the power generation module 10 according to the first embodiment. In the first embodiment, a high voltage of approximately 20 V to 25 V can be obtained by superimposing a voltage waveform due to the large Barkhausen effect, which has a significant peak voltage, on a voltage waveform with a large amount of charge due to electromagnetic induction. Efficient charging of a capacitor requires both a large potential difference and a large amount of charge. The power generation module according to the first embodiment, which can generate an induced voltage with the waveform shown in FIG. 7 , is particularly suitable for charging a capacitor.
[0033] Fig. 8 is a diagram showing the relationship between the magnetic field strength H applied to the power generating element unit 100, 100a and the generated power P. As shown by the dashed line in Fig. 8, if the magnetic body 110 is formed only from an iron core, the amount of power generated varies in proportion to the strength of the applied magnetic field, and when the strength of the magnetic field H is B or less, the amount of power generated is almost zero. However, as shown by the solid line in Fig. 8, if the magnetic body 110 has a magnetic core 111 made of a composite magnetic wire, a certain amount of power generation is always obtained as long as there is a magnetic field equal to or greater than the power generation threshold of the composite magnetic wire (magnetic field strength A lower than strength B). This makes it possible to improve power generation efficiency.
[0034] FIG. 9B is a side view schematically illustrating the configuration (bobbin shape) of the power generating element unit 100. The magnetic body 110 includes a composite magnetic wire that is a magnetic core 111 that generates a large Barkhausen effect in response to a change in magnetic flux. The magnetic body 110 preferably includes a magnetic collector (soft magnetic material) 112 that surrounds the outer periphery of the magnetic core 111. In the example of FIG. 9, the magnetic body 110 has a bobbin shape. In other words, the magnetic body 110 has a bobbin shape in which the first magnetic collector surface 110a and the second magnetic collector surface 110b each have a larger diameter than the central portion of the magnetic body 110 between the first magnetic collector surface 110a and the second magnetic collector surface 110b (i.e., a larger diameter than the inner diameter of the coil 120). The magnetic body 110 is also referred to as a magnetic bobbin. In this case, the magnetic flux is collected by the large-diameter first magnetic flux collecting surface 110a and second magnetic flux collecting surface 110b and guided to the magnetic core 111, thereby improving power generation efficiency. Note that the magnetic body 110 of the power generation element section 100 can also be made of iron, i.e., a magnetic collecting body (soft magnetic body), but the provision of the magnetic core 111 that generates the large Barkhausen effect improves power generation efficiency.
[0035] FIG. 9(A) is a perspective view schematically illustrating a certain configuration of the power generating element unit 100, and FIG. 9(B) is a side view thereof. The magnetic body 110 has a composite magnetic wire that is a magnetic core 111 that generates a large Barkhausen effect in response to a change in magnetic flux. The magnetic body 110 preferably has a magnetic collector (soft magnetic material) 112 surrounding the outer periphery of the magnetic core 111. In the examples of FIGS. 9(A) and 9(B), the magnetic body 110 has a bobbin shape. In other words, the magnetic body 110 has a bobbin shape in which the first magnetic collector surface 110a and the second magnetic collector surface 110b each have a larger diameter than the central portion of the magnetic body 110 between the first magnetic collector surface 110a and the second magnetic collector surface 110b (i.e., a larger diameter than the inner diameter of the coil 120). The magnetic body 110 is also referred to as a magnetic bobbin. In a direction perpendicular to the direction in which the magnetic core 111 extends (Y direction), the size of the magnetic collector 112 is larger than the size of the magnetic core 111. In this case, the magnetic flux is collected by the large-diameter first magnetic collector surface 110a and second magnetic collector surface 110b and guided to the magnetic core 111, improving power generation efficiency. Note that the magnetic body 110 of the power generation element section 100 can also be made of iron, i.e., a magnetic collector (soft magnetic material); however, providing the magnetic core 111 that generates the large Barkhausen effect improves power generation efficiency.
[0036] FIG. 10(A) is a perspective view schematically illustrating a configuration of the power generating element unit 100 different from the configurations illustrated in FIGS. 9(A) and 9(B), and FIG. 10(B) is a side view thereof. In the examples illustrated in FIGS. 10(A) and 10(B), the magnetic body 110 has a bobbin shape. In this case, the magnetic body 110 is also referred to as a magnetic bobbin. The coil 120 is wound around a narrowed portion of the magnetic bobbin. When viewed in a plane perpendicular to the Y axis, the outer shape of the end portion of the magnetic core 111 is larger than the outer shape of the central portion of the magnetic core 111. The magnetic body 110 has a bobbin shape in which the first magnetic field collecting surface 110a and the second magnetic field collecting surface 110b each have a larger diameter than the central portion of the magnetic body between the first magnetic field collecting surface 110a and the second magnetic field collecting surface 110b.
[0037] The magnetic material 110 of the power generating element section 100 can be made only of a soft magnetic material such as iron as shown in FIGS. 10(A) and (B). However, by providing a magnetic material core 111 that generates a large Barkhausen effect as shown in FIGS. 9(A) and (B), power generation efficiency can be improved.
[0038] As described above, in the power generation module 10 according to embodiment 1, the diameter is larger than the central part of the magnetic material 110 of the power generation element section 1 (i.e., larger than the inner diameter of the coil 120), and many magnetic lines of force are collected and guided to the magnetic material core 111, thereby improving power generation efficiency.
[0039] Furthermore, when a composite magnetic wire that generates a large Barkhausen effect is used as the magnetic core 111, the amount of charge is small, but it is suitable for charging a capacitor.
[0040] Furthermore, when a composite magnetic wire that generates the large Barkhausen effect is used as the magnetic core 111 and a soft magnetic material that surrounds the magnetic core 111 is provided as the magnetic collector 112, the magnetic lines of force can be collected from the first magnetic collector surface 110a via the magnetic collector 112 to the magnetic core 111 that generates the large Barkhausen effect, thereby achieving the effects of enabling power generation with high power generation efficiency and being suitable for charging a capacitor.
[0041] Furthermore, when the magnetic core is made of a soft magnetic material such as an iron core, the magnetic collector and the magnetic core can be integrated using the same material.
[0042] Furthermore, when a bobbin-shaped magnetic body 110 as shown in FIG. 9 is used, the process of winding the coil 120 can be automated, enabling cost reduction in terms of both materials and labor.
[0043] 11 is a block diagram schematically illustrating the configuration of a sensor unit 62 of a current sensor 60 according to embodiment 2. The sensor unit 62 of the current sensor 60 has one or more power generation element units 100a, a rectifier 51a, and a processing unit 61. As with the power generation element units 100 described in embodiment 1, each power generation element unit 100a has a magnetic body 110 and a coil 120 wound around the magnetic body 110, with one end of the magnetic body 110 being a first magnetic flux collecting surface 110a and the other end of the magnetic body 110 being a second magnetic flux collecting surface 110b. When the magnetic body 110 is near the electric wire 200 through which an alternating current flows, magnetic field lines M generated by the current penetrate the first magnetic field collecting surface 110a, the magnetic body 110, and the second magnetic field collecting surface 110b, generating a voltage in the coil 120. The processing unit 61 calculates and outputs the current flowing through the electric wire 200 based on the voltage generated in the coil of the power generating element unit 100a. The processing unit 61 is, for example, a processing circuit. The processing unit 61 may also be, for example, a processor that executes a software program.
[0044] Fig. 12 is a block diagram schematically illustrating the configuration of a modified example of the current sensor 60 according to the second embodiment. The configuration of Fig. 12 differs from the configuration of Fig. 5 in that the power generation device 50 supplies power to the current sensor 60, rather than to the environment sensor 58. The current sensor 60 of Fig. 12 includes a wireless transmitter 56 that receives power stored in the power storage unit 52 of the power generation device 50 and transmits information about the current sensed by the power generation element unit 100a (i.e., also a current detection element unit) of the current sensor 60, and a switching unit 53 that switches between an ON state in which the power stored in the power storage unit 52 is supplied to the wireless transmitter 56 and an OFF state in which power is not supplied to the wireless transmitter 56.
[0045] The current sensor 60 receives the power stored in the power storage unit 52 of the power generation device 50. The current sensor 60 includes, for example, a sensor unit 62 that senses the current in an electric wire of a machine tool, which is an example of a monitored object; a wireless transmitter unit 56 that transmits information sensed by the sensor unit 62 to a control device 57 of the machine tool; and a switching unit 53 that switches between an ON state in which the power stored in the power storage unit 52 of the power generation device 50 is supplied to the wireless transmitter unit 56 and an OFF state in which power is not supplied to the wireless transmitter unit 56. The current sensor 60 also includes a voltage monitoring unit 54 that monitors the internal voltage of the power storage unit 52 and switches the switching unit 53 to the ON state when the internal voltage exceeds the minimum drive voltage required for operation of the wireless transmitter unit 56. Note that while FIG. 12 illustrates the power generation device 50 and the current sensor 60 as separate devices, the power generation device 50 may be part of the current sensor 60 (e.g., a system including the current sensor 60). The control device 57 can control the operation of the machine tool (such as emergency stop, issuing an alarm, and recording the sensing information) based on the sensing information received from the current sensor 60. In addition, the sensor unit 55 can be supplied with power stored in the power storage unit 52.
[0046] If the power generated by the power generation module 10 is directly sent to the sensor unit 62 and wireless transmitter 56 via the power storage unit 52, natural discharge occurs when power is not being generated, causing the internal voltage of the power storage unit 52 to drop rapidly. By providing the voltage monitoring unit 54 and the switching unit 53, the switch is kept in an off state until the voltage required for the operation of the sensor unit 55 and wireless transmitter 56 is accumulated. This type of control allows for efficient charging without losing charge.
[0047] Except for the above, the second embodiment is the same as the first embodiment.
[0048] 10 Power generation module, 50 Power generation device, 51, 51a Rectifier, 52 Storage unit, 53 Switching unit, 54 Voltage monitoring unit, 55 Sensor unit, 56 Wireless transmission unit, 57 Control device, 58 Environmental sensor, 60 Current sensor, 61 Processing unit, 62 Sensor unit, 100, 100a Power generation element unit, 110 Magnetic material, 110a First magnetic field collecting surface, 110b Second magnetic field collecting surface, 111 Magnetic core, 112 Magnetic field collecting material, 120 Coil, 150, 150a Holding unit, 200 Electric wire, M Magnetic field line.
Claims
1. Having one or more power generation elements, Each of the one or more power generation elements comprises a magnetic material and a coil wound around the magnetic material. The magnetic material is A magnetic core that generates a large Barkhausen effect in response to changes in magnetic flux, A magnetic material collecting body, which is a soft magnetic material, surrounds the outer circumference near the end of the aforementioned magnetic core, It has, In a direction perpendicular to the direction in which the magnetic core extends, the size of the magnetic collector is larger than the size of the magnetic core. One end of the magnetic material is a first magnetic field collecting surface, and the other end of the magnetic material is a second magnetic field collecting surface. When the magnetic material is near a wire carrying alternating current, the magnetic field lines generated by the current penetrate the first magnetic collecting surface, the magnetic material, and the second magnetic collecting surface, generating a voltage in the coil. A power generation module characterized by the following features.
2. An environmental sensor that receives power stored in the energy storage unit of a power generation device, A sensor unit that senses the environment or state, A wireless transmission unit that transmits information sensed by the aforementioned sensor unit, A switching unit that switches between an ON state, which supplies the power stored in the power storage unit to the wireless transmitter, and an OFF state, which does not supply the power to the wireless transmitter; It has, The aforementioned power generation device is A power generation module having one or more power generation elements, One or more rectifiers that rectify the voltage generated in the coils of one or more of the aforementioned power generation elements, The energy storage unit stores the power output from one or more rectifiers, It has, Each of the one or more power generation elements comprises a magnetic material and a coil wound around the magnetic material. One end of the magnetic material is a first magnetic field collecting surface, and the other end of the magnetic material is a second magnetic field collecting surface. When the magnetic material is near a wire through which an alternating current flows, the magnetic field lines generated by the current penetrate the first magnetic collecting surface, the magnetic material, and the second magnetic collecting surface, and the voltage is generated in the coil. An environmental sensor characterized by the following features.
3. The system further includes a voltage monitoring unit that monitors the internal voltage of the energy storage unit and, when the internal voltage becomes equal to or greater than the minimum drive voltage required for the operation of the wireless transmitter, turns the switching unit into the ON state. The environmental sensor according to feature 2.
4. One or more power generation elements, Processing unit and It has, Each of the one or more power generation elements comprises a magnetic material and a coil wound around the magnetic material. The magnetic material is A magnetic core that generates a large Barkhausen effect in response to changes in magnetic flux, A magnetic material collecting body, which is a soft magnetic material, surrounds the outer circumference near the end of the aforementioned magnetic core, It has, In a direction perpendicular to the direction in which the magnetic core extends, the size of the magnetic collector is larger than the size of the magnetic core. One end of the magnetic material is a first magnetic field collecting surface, and the other end of the magnetic material is a second magnetic field collecting surface. When the magnetic material is in the vicinity of a wire through which an alternating current flows, the magnetic field lines generated by the current penetrate the first magnetic collecting surface, the magnetic material, and the second magnetic collecting surface, and a voltage is generated in the coil. The processing unit calculates and outputs the current flowing through the electric wire based on the voltage generated in the coil of one or more power generation elements. A current sensor characterized by the following features.
5. A current sensor that receives power stored in the energy storage unit of a power generation device and senses the current, A wireless transmitter that transmits the sensed current information, A switching unit that switches between an ON state, which supplies the power stored in the power storage unit to the wireless transmitter, and an OFF state, which does not supply the power to the wireless transmitter; It has, The aforementioned power generation device is A power generation module having one or more power generation elements, One or more rectifiers that rectify the voltage generated in the coils of one or more of the aforementioned power generation elements, The energy storage unit stores the power output from one or more rectifiers, It has, Each of the one or more power generation elements comprises a magnetic material and a coil wound around the magnetic material. One end of the magnetic material is a first magnetic field collecting surface, and the other end of the magnetic material is a second magnetic field collecting surface. When the magnetic material is near a wire through which an alternating current flows, the magnetic field lines generated by the current penetrate the first magnetic collecting surface, the magnetic material, and the second magnetic collecting surface, and the voltage is generated in the coil. A current sensor characterized by the following features.