Patent Description:
A system for monitoring devices such as social infrastructure without human intervention to transmit the monitoring result using wireless communication or the like is proposed. In a conventional system, in order to reduce power consumption, power consumption is reduced in a standby state where monitoring is not performed as compared with an operation state where monitoring is performed, thereby saving power (see Patent Literature <NUM>). Document <CIT> teaches a measurement system according to the preamble of claim <NUM>.

In a terminal device in a system in Patent Literature <NUM>, an operation state and a standby state with low power consumption are switched in order to reduce power. However, since switching from the standby state to the operation state is performed based on an input signal acquired from an object to be monitored, power required to receive the input signal is always consumed even in the standby state with low power consumption. Thus, the power consumption in the standby state cannot be sufficiently reduced.

According to a first aspect, a measurement system includes a vibration generation unit that generates sound or vibration in response to a change in environmental state quantity, a vibration-driven energy harvesting unit that generates electric power using the sound or vibration generated by the vibration generation unit, and a transmission unit that is driven with the electric power generated by the vibration-driven energy harvesting unit and transmits predetermined information. The vibration generation unit includes a deformation member whose shape suddenly changes from a first shape to a second shape in response to a change in the environmental state quantity.

According to a second aspect, a diagnosis system includes the measurement system of the first aspect arranged near an object to be diagnosed and a reception system for receiving a signal transmitted from the measurement system and diagnosing a state of the object to be diagnosed based on the signal.

According to the present invention, the power consumption of the measurement system can be significantly reduced.

Hereinafter, a measurement system <NUM> of a first embodiment will be described with reference to <FIG>.

<FIG> is a diagram showing a schematic configuration of the measurement system <NUM> of the first embodiment. The measurement system <NUM> includes a vibration generation unit <NUM> that generates sound or vibration in response to a change in environmental state quantity such as temperature, pressure, and flow rate, a vibration-driven energy harvesting unit <NUM> that generates electric power using the sound or vibration generated by the vibration generation unit <NUM>, and a transmission unit <NUM> that transmits predetermined information. <FIG> shows the vibration-driven energy harvesting unit <NUM> and the transmission unit <NUM>, each surrounded by a broken line.

The vibration-driven energy harvesting unit <NUM> includes a vibration-driven energy harvesting element <NUM> which is an electret energy harvesting element, a piezo energy harvesting element, an electromagnetic induction energy harvesting element, or a magnetostriction energy harvesting element. The vibration-driven energy harvesting element <NUM> generates AC power having a frequency equal to the frequency of sound or vibration. The electric power generated by the vibration-driven energy harvesting element <NUM> is conveyed through connection wirings <NUM>, <NUM> to a full-wave rectifying rectification circuit <NUM> including four rectifier elements as an example, rectified by the rectification circuit <NUM>, and stored in a capacitor <NUM>. Then, the electric power is converted into a predetermined voltage by a voltage converter (DC/DC converter) <NUM> and a power storage unit <NUM> including a capacitor or a storage battery is charged with the electric power.

The rectification circuit <NUM> is not limited to the full-wave rectifying one but may be a half-wave rectifying one.

One example is that one end (lower end in <FIG>) of the power storage unit <NUM> is connected to the ground. Hereinafter, a voltage at the other end (upper end in <FIG>) of the power storage unit <NUM> will be referred to as an output voltage V1.

The output voltage V1 based on the electric power generated by the vibration-driven energy harvesting unit <NUM> is input into a VCC terminal which is a power supply terminal of a communication circuit <NUM> constituting the transmission unit <NUM>. One example is that the communication circuit <NUM> is a communication circuit including an amplification element such as a transistor, a vibrator element, and a frequency selection filter element such as a SAW device. An RF terminal of the communication circuit <NUM> is connected to an antenna <NUM> and a GND terminal is connected to the ground.

The communication circuit <NUM> is activated when a voltage higher than a first voltage which is a reference voltage is input into the VCC terminal and, as an example, outputs a high frequency signal including an identification signal unique to the measurement system <NUM> from the RF terminal to the antenna <NUM>. That is, a signal including a unique identification signal is transmitted from the antenna <NUM> to the outside as a radio wave. The identification signal may be one obtained by making information on numbers into a signal or making information on alphabetical letters into a signal.

Although a configuration of the vibration generation unit <NUM> will be described later in detail, the vibration generation unit <NUM> generates sound or vibration when an environmental state quantity such as temperature, pressure, and flow rate substantially reaches a predetermined value. Using the sound or vibration generated at that time, the vibration-driven energy harvesting unit <NUM> including the vibration-driven energy harvesting element <NUM> generates electric power, and the output voltage V1 of the vibration-driven energy harvesting unit <NUM> rises to a voltage higher than the first voltage described above. As a result, the communication circuit <NUM> is activated and a signal including the identification signal unique to the measurement system <NUM> is transmitted from the antenna <NUM> to the outside as a radio wave.

On the other hand, in a case where the environmental state quantity such as temperature, pressure, and flow rate does not reach the predetermined value described above, the vibration generation unit <NUM> does not generate sound or vibration, and the vibration-driven energy harvesting unit <NUM> does not generate electric power. Alternatively, even in a case where the vibration-driven energy harvesting unit <NUM> generates electric power using sound or vibration existing in the environment, the amount of generated power is small. Thus, even the voltage converter <NUM> cannot increase the output voltage V1 to the first voltage described above to activate the communication circuit <NUM>. Therefore, a radio wave including the identification signal unique to the measurement system <NUM> is not transmitted from the antenna <NUM> to the outside.

Accordingly, a reception system <NUM> of the outside shown in <FIG>, which will be described later, can detect that the environmental state quantity such as temperature, pressure, and flow rate measured by the measurement system <NUM> has substantially reached the predetermined value by detecting the signal (radio wave) transmitted from the measurement system <NUM>.

Incidentally, the signal transmitted from the transmission unit <NUM> is not limited to a radio signal transmitted via radio waves but may be an electric signal transmitted via a wire or a signal transmitted via light.

Although <FIG> shows an example in which the vibration generation unit <NUM> and the vibration-driven energy harvesting unit <NUM> are separated, at least a portion of the vibration-driven energy harvesting unit <NUM> may be included in the vibration generation unit <NUM> as described later. On the contrary, at least a portion of the vibration generation unit <NUM> may be included in the vibration-driven energy harvesting unit <NUM>.

A vibration generation unit 20a, which is a first example of the vibration generation unit <NUM>, will be described with reference to <FIG>. In the first example shown in <FIG>, the vibration-driven energy harvesting element <NUM> of the vibration generation unit <NUM> is arranged inside the vibration generation unit 20a.

The vibration generation unit 20a has a housing including a case <NUM>, a cap <NUM>, a guide <NUM>, and the like and, in the housing, has the vibration-driven energy harvesting element <NUM> and a disk-shaped bimetal (bimetal disc) <NUM> as an example of a member whose shape changes due to a temperature change to generate sound or vibration. The bimetal <NUM> is, as an example, made by laminating two types of metal plates with different linear expansion rates, at least one metal plate of which has relatively high rigidity. The bimetal <NUM> is installed in a cavity formed by the cap <NUM> and the guide <NUM>.

<FIG> shows the vibration generation unit 20a in a state where the temperature is relatively low. At this time, the shape of the bimetal <NUM> is an upwardly convex curved shape in <FIG> (a first shape in the first example). An actuation pin <NUM> is arranged so as to penetrate a through hole (not shown) provided in the guide <NUM>. One end of the actuation pin <NUM> is in contact with a substantial center of the bimetal <NUM>, and the other end is in contact with a pressing unit 26a of a spring member <NUM>. The lower end of the spring member <NUM> is fixed to the case <NUM> and the elastic force of the spring member <NUM> causes the pressing unit 26a of the spring member <NUM> to push up the actuation pin <NUM> upward.

<FIG> shows a moment when the bimetal <NUM> is deformed due to an increase in temperature and a warp is suddenly reversed and takes a downwardly convex shape (a second shape in the first example). An impact force accompanying the reversal of the bimetal <NUM> is conveyed to the pressing unit 26a of the spring member <NUM> through the actuation pin <NUM> to elastically deform the spring member <NUM> suddenly. As a result, a hammer <NUM> provided at a substantially tip portion of the spring member <NUM> suddenly moves and hits the vibration-driven energy harvesting element <NUM> from an upper surface. The vibration-driven energy harvesting element <NUM> is supported by the case <NUM> via an elastic body <NUM> including rubber or a spring and vibrates by being hit by the hammer <NUM>.

The vibration-driven energy harvesting element <NUM> generates electric power using the vibration or sound generated at that time. The generated electric power is input into the rectification circuit <NUM> shown in <FIG> through the connection wirings <NUM>, <NUM> connected to the outside of the vibration generation unit 20a via an introduction unit <NUM>. Then, the transmission unit <NUM> of the measurement system <NUM> shown in <FIG> is activated with the electric power generated by the vibration-driven energy harvesting element <NUM>, and the signal including the identification signal unique to the measurement system <NUM> is transmitted from the antenna <NUM> to the outside as a radio wave.

Thus, by using the bimetal <NUM> whose shape suddenly changes (reverses) from the first shape to the second shape at predetermined temperature, the measurement system <NUM> for transmitting a predetermined signal to the outside can be implemented when the temperature of the environment in which the vibration generation unit 20a is installed changes and substantially rises to the predetermined temperature.

<FIG> shows a state after the hammer <NUM> hits the vibration-driven energy harvesting element <NUM>. Due to the elastic force of the spring member <NUM>, the hammer <NUM> provided in the spring member <NUM> separates from the vibration-driven energy harvesting element <NUM>.

Then, when the temperature around the vibration generation unit 20a drops, the shape of the bimetal <NUM> returns to an upwardly convex and warped state as shown in <FIG>. However, in this case, the hammer <NUM> provided in the spring member <NUM> moves upward and does not hit the vibration-driven energy harvesting element <NUM>, and the vibration-driven energy harvesting element <NUM> does not generate electric power.

By appropriately setting a distance between the hammer <NUM> and the vibration-driven energy harvesting element <NUM>, the elastic constant of the spring member <NUM>, and the like, the hammer <NUM> may be configured to hit the vibration-driven energy harvesting element <NUM> only once when the bimetal <NUM> is reversed as the temperature rises.

By arranging the bimetal <NUM> upside down as opposed to the above example, the hammer <NUM> may be configured to hit the vibration-driven energy harvesting element <NUM> when the temperature drops so that the vibration-driven energy harvesting element <NUM> may generate electric power.

A vibration generation unit 20b of a second example will be described with reference to <FIG>. The major portion of the vibration generation unit 20b of the second example is identical to the vibration generation unit 20a of the first example described above. Accordingly, descriptions will be given below of differences from the vibration generation unit 20a of the first example in particular, and descriptions of common configurations will be omitted as appropriate.

<FIG> shows the vibration generation unit 20b of the second example in a state where the temperature is relatively low. In contrast to the vibration generation unit 20a of the first example, in the vibration generation unit 20b of the second example, the vibration-driven energy harvesting element <NUM> is supported by the guide <NUM> via the elastic body <NUM>. Further, the bimetal <NUM> is warped in a downwardly convex shape (the first shape in the second example) at low temperature. In this state, the pressing unit 26a of the spring member <NUM> is pushed downward by the bimetal <NUM> from above via the actuation pin <NUM>.

<FIG> shows a moment when the bimetal <NUM> is deformed due to an increase in temperature and a warp is reversed and takes an upwardly convex shape (the second shape in the second example). At this time, since a force for pushing the pressing unit 26a of the spring member <NUM> downward is released, the hammer <NUM> provided in the spring member <NUM> suddenly moves upward due to the elastic force of the spring member <NUM> and hits the vibration-driven energy harvesting element <NUM>. This generates vibration or sound and the vibration-driven energy harvesting element <NUM> generates electric power using the vibration or sound.

Then, the transmission unit <NUM> of the measurement system <NUM> shown in <FIG> is activated using electric power generated by the vibration-driven energy harvesting element <NUM>, and the signal including the identification signal unique to the measurement system <NUM> is transmitted from the antenna <NUM> to the outside as a radio wave.

After that, the hammer <NUM> provided in the spring member <NUM> separates from the vibration-driven energy harvesting element <NUM> due to a restoring force of the spring member <NUM> and rests in a position away from the vibration-driven energy harvesting element <NUM>.

Then, when the temperature around the vibration generation unit 20b drops, the shape of the bimetal <NUM> returns to a downwardly convex and warped state as shown in <FIG>. At this time, the bimetal <NUM> suddenly moves the hammer <NUM> provided in the spring member <NUM> downward through the actuation pin <NUM>. However, the hammer <NUM> moves in a direction away from the vibration-driven energy harvesting element <NUM> and does not hit the vibration-driven energy harvesting element <NUM>, and therefore the vibration-driven energy harvesting element <NUM> does not generate electric power.

In the vibration generation unit 20b of the second example, the hammer <NUM> hits the vibration-driven energy harvesting element <NUM> using the elastic force of the spring member <NUM>, not an impact force itself generated by the bimetal <NUM> which is suddenly deformed due to a temperature change. Thus, a striking force for hitting the vibration-driven energy harvesting element <NUM> can be set to a substantially constant magnitude. Accordingly, it is possible to cause the vibration-driven energy harvesting element <NUM> to generate electric power stably.

Incidentally, also in the vibration generation unit 20b of the second example, by arranging the bimetal <NUM> upside down as opposed to the above example, the hammer <NUM> may be configured to hit the vibration-driven energy harvesting element <NUM> when the temperature drops, so that the vibration-driven energy harvesting element <NUM> may generate electric power.

A vibration generation unit 20c of a third example will be described with reference to <FIG>. The major portion of the vibration generation unit 20c of the third example is identical to the vibration generation unit 20a of the first example described above. Accordingly, descriptions will be given below of differences from the vibration generation unit 20a of the first example in particular, and descriptions of common configurations will be omitted as appropriate.

<FIG> shows the vibration generation unit 20c of the third example in a state where the temperature is relatively low. The bimetal <NUM> in the vibration generation unit 20c of the third example is warped in a downwardly convex shape (the first shape in the third example) at low temperature.

When the temperature around the vibration generation unit 20c rises to predetermined temperature or higher, the bimetal <NUM> is suddenly deformed into an upwardly convex shape (the first shape in the third example). As a result, the actuation pin <NUM> is suddenly moved upward by the bimetal <NUM> and hits the vibration-driven energy harvesting element <NUM>. This generates vibration or sound and the vibration-driven energy harvesting element <NUM> generates electric power using the vibration or sound.

Since the spring member <NUM> can be omitted, the configuration of the vibration generation unit 20c of the third example is simple and it is possible to cut down on the cost as compared with the configurations of the vibration generation unit 20a of the first example and the vibration generation unit 20b of the second example.

On the other hand, the configurations of the vibration generation unit 20a of the first example and the vibration generation unit 20b of the second example have an effect that the directions of the vibration generation units 20a and 20b can be arranged regardless of the direction of gravity.

Incidentally, in any of the respective vibration generation units 20a to 20c of the first to third examples, a position where the vibration-driven energy harvesting element <NUM> is installed is not limited to the inside of the vibration generation units 20a to 20c but may be the vicinities of the vibration generation units 20a to 20c.

In the respective vibration generation units 20a to 20c of the first to third examples, it can be said that the bimetal <NUM> is a deformation member whose shape suddenly changes from the first shape to the second shape in response to a change in temperature as an environmental state quantity.

A vibration generation unit 20d of a fourth example will be described with reference to <FIG>. The vibration generation unit 20d of the fourth example has many portions in common with the vibration generation unit 20c of the third example described above. Thus, descriptions will be given below of differences from the vibration generation unit 20c of the third example in particular, and descriptions of common configurations will be omitted as appropriate.

The vibration generation unit 20d of the fourth example generates sound or vibration according to pressure which is an example of the environmental state quantity. As in the case of the vibration generation unit 20c of the third example, the vibration generation unit 20d has a housing including the case <NUM>, the cap <NUM>, a guide <NUM>, and the like and has the vibration-driven energy harvesting element <NUM> and a pressure bulkhead <NUM> in the housing.

The pressure bulkhead <NUM> is provided as a bulkhead between airtight space <NUM> and open space <NUM> formed by the guide <NUM> and the airtight space <NUM> is made airtight with respect to the open space <NUM> by the pressure bulkhead <NUM> and a support unit <NUM>. On the other hand, the open space <NUM> is connected to the outside through a ventilation hole <NUM>, and pressure inside the open space <NUM> is the same as external pressure (atmospheric pressure).

The pressure bulkhead <NUM> is, as an example, a metal plate with relatively high rigidity and has a concave shape with respect to an airtight space <NUM> side due to a pressure difference between gas in the airtight space <NUM> and gas in the open space <NUM>. The actuation pin <NUM> is arranged on the pressure bulkhead <NUM> and is arranged so that the upper end of the actuation pin <NUM> faces the vibration-driven energy harvesting element <NUM> via a through hole provided in the guide <NUM>. A vacuum bellows <NUM> is provided between the actuation pin <NUM> and the guide <NUM> to keep airtightness between the actuation pin <NUM> and the guide <NUM>.

Incidentally, in a case where the airtightness between the actuation pin <NUM> and the guide <NUM> is sufficiently kept, the vacuum bellows <NUM> does not need to be provided.

When the atmospheric pressure rises above a predetermined value, the pressure in the open space <NUM> rises and the pressure bulkhead <NUM> is suddenly deformed so as to be in a convex shape with respect to the airtight space <NUM> side.

This deformation pushes the actuation pin <NUM> upward and causes the actuation pin <NUM> to collide with the vibration-driven energy harvesting element <NUM>, and the vibration-driven energy harvesting element <NUM> vibrates.

On the other hand, when the atmospheric pressure drops, the pressure in the open space <NUM> also drops, and when the difference between the pressure in the open space <NUM> and the pressure in the airtight space <NUM> becomes a predetermined value or more, the pressure bulkhead <NUM> is deformed into the original concave shape with respect to the airtight space <NUM> side.

Incidentally, the vibration generation unit 20d of the fourth example is not necessarily limited to the configuration of generating sound in response to the change in atmospheric pressure described above but can be configured to generate sound according to atmospheric pressure and hydraulic pressure (water pressure) inside an object to be measured. This only requires, for example, introducing gas or liquid inside the object to be measured into the open space <NUM> through the ventilation hole <NUM>.

In the vibration generation unit 20d of the fourth example, the pressure bulkhead <NUM> can be said to be a deformation member whose shape suddenly changes from the first shape to the second shape in response to a change in pressure as an environmental state quantity.

A vibration generation unit 20e of a fifth example will be described with reference to <FIG>. The vibration generation unit 20e of the fifth example has many portions in common with the vibration generation unit 20c of the third example described above. Accordingly, descriptions will be given below of differences from the vibration generation unit 20c of the third example in particular, and descriptions of common configurations will be omitted as appropriate.

The vibration generation unit 20e of the fifth example generates sound or vibration according to flow rate which is an example of an environmental state quantity. As is the case with the vibration generation unit 20c of the third example, the vibration generation unit 20e has a housing including the case <NUM>, a guide <NUM>, and the like and has the vibration-driven energy harvesting element <NUM> and a variation unit <NUM> in the housing. The variation unit <NUM> is, as an example, a metal plate with relatively high rigidity and has a concave curved surface shape with respect to the actuation pin <NUM>. An end of the variation unit <NUM> is fixed to an inner wall of the guide <NUM> by a support unit <NUM>.

A lower end of the guide <NUM> is fixed to a side surface of a pipe <NUM>. A substantially L-shaped paddle <NUM> is rotatably inserted into the pipe <NUM> using a fulcrum <NUM> as a rotary shaft. A first portion 54a of the paddle <NUM> is inside the pipe <NUM>, and a second portion 54b of the paddle <NUM> is outside the pipe <NUM> and is arranged such that a pressing unit <NUM> provided on the second portion 54b faces the variation unit <NUM>.

As shown in <FIG>, when a fluid <NUM> flows inside the pipe <NUM> in a direction indicated by arrows, a force for rotating the paddle <NUM> counterclockwise using the fulcrum <NUM> as a rotary shaft is applied to the first portion 54a of the paddle <NUM>. This force is conveyed to the second portion 54b of the paddle <NUM>, and the pressing unit <NUM> provided on the second portion 54b pushes the variation unit <NUM> upward.

When the flow rate of the fluid <NUM> flowing inside the pipe <NUM> becomes a predetermined value or higher, a force with which the pressing unit <NUM> pushes the variation unit <NUM> upward becomes larger, and the variation unit <NUM> is suddenly deformed so that the shape of the variation unit <NUM> is a convex shape with respect to the actuation pin <NUM>.

On the other hand, when the flow rate of the fluid <NUM> flowing inside the pipe <NUM> becomes less than a predetermined value, the force with which the pressing unit <NUM> pushes the variation unit <NUM> upward becomes smaller, and the variation unit <NUM> is returned to the original shape which is a concave shape with respect to the actuation pin <NUM> due to the weight of the actuation pin <NUM> or the like.

In the vibration generation unit 20e of the fifth example, it can be said that the paddle <NUM> is a displacement unit in which the position of the second portion 54b changes in response to a change in flow rate. It can also be said that the variation unit <NUM> is a deformation member whose shape suddenly changes from the first shape to the second shape according to the position of the paddle <NUM> (displacement unit).

In the respective vibration generation units 20a to 20e of the first to fifth examples described above, a sudden change in the shapes of the bimetal <NUM>, the pressure bulkhead <NUM>, and the variation unit <NUM> moves the actuation pin <NUM>, and the vibration-driven energy harvesting element <NUM> generates electric power using vibration generated by the collision of the actuation pin <NUM> with the vibration-driven energy harvesting element <NUM>. However, the vibration-driven energy harvesting element <NUM> may generate electric power using sound generated when the bimetal <NUM>, the pressure bulkhead <NUM>, and the variation unit <NUM> are suddenly deformed without providing the actuation pin <NUM>.

A vibration generation unit 20f of a sixth example will be described with reference to <FIG>. The vibration generation unit 20f of the sixth example has many portions in common with the vibration generation unit 20d of the fourth example described above. Accordingly, descriptions will be given below of differences from the vibration generation unit 20d of the fourth example in particular, and descriptions of common configurations will be omitted as appropriate.

As in the case of the vibration generation unit 20d of the fourth example, the vibration generation unit 20f of the sixth example also generates sound or vibration according to pressure which is an example of an environmental state quantity. The vibration generation unit 20f has a housing including the case <NUM>, the guide <NUM>, and the like and has the vibration-driven energy harvesting element <NUM> and a movable plate <NUM> in the housing. An upper surface 41T of the guide <NUM> is inclined with respect to a horizontal plane, and a sphere <NUM> is placed on the upper surface 41T.

The vibration-driven energy harvesting element <NUM> is arranged via the elastic body <NUM> on the floor surface of the case <NUM> in the vicinity of the lower side of the inclined upper surface 41T. As will be described later, the vibration-driven energy harvesting element <NUM> is arranged in a position where the sphere <NUM> rolled down from the upper surface 41T falls.

The movable plate <NUM> is provided as a bulkhead between the airtight space <NUM> and the open space <NUM> formed by the guide <NUM>, and the airtight space <NUM> is made airtight with respect to the open space <NUM> by the movable plate <NUM> and the support unit <NUM> and, as an example, is kept at atmospheric pressure higher than <NUM> atm. On the other hand, the open space <NUM> is connected to the outside through the ventilation hole <NUM> and the pressure inside the open space <NUM> is the same as the external pressure (atmospheric pressure).

The movable plate <NUM> is, as an example, a metal plate which has relatively low rigidity and is deformed according to a pressure difference between the airtight space <NUM> and the open space <NUM>. The actuation pin <NUM> is arranged on the movable plate <NUM>, and an upper end 25T of the actuation pin <NUM> projects onto the upper surface 41T of the guide <NUM> through the through hole provided in the guide <NUM>. The upper end 25T of the actuation pin <NUM> prevents the sphere <NUM> from rolling down the upper surface 41T.

In the vibration generation unit 20f, a vacuum bellows <NUM> is provided between the actuation pin <NUM> and the guide <NUM> so that the pressure in the open space <NUM> is not conveyed to the space in which the vibration-driven energy harvesting element <NUM> is arranged.

When the external pressure (atmospheric pressure) rises, the atmospheric pressure in the open space <NUM> increases, and the movable plate <NUM> is gradually deformed and pushed downward. Thus, the position of the upper end 25T of the actuation pin <NUM> also gradually moves downward. Then, when the external pressure reaches predetermined pressure, the sphere <NUM> rolls down the upper surface 41T without being held by the upper end 25T of the actuation pin <NUM>, becomes a sphere 57f shown by a broken line, and falls on the vibration-driven energy harvesting element <NUM>.

The fall of the sphere 57f generates vibration in the vibration-driven energy harvesting element <NUM>, and sound is also generated accordingly. Thus, even in the vibration generation unit 20f of the sixth example, sound or vibration is generated in response to a change in pressure which is an environmental state quantity. Further, the vibration-driven energy harvesting element <NUM> generates electric power using the sound or vibration generated by the fall of the sphere 57f.

Incidentally, the vibration-driven energy harvesting element <NUM> may be covered with a resonance plate (not shown) made of metal or the like and may be caused to generate electric power using sound generated from the resonance plate when the sphere 57f is dropped on the resonance plate.

It should be noted that as in the case of the vibration generation unit 20d of the fourth example described above, sound may be generated according to the atmospheric pressure and hydraulic pressure (water pressure) inside the object to be measured also in the vibration generation unit 20f of the sixth example.

The vibration generation unit 20f of the sixth example described above uses the movable plate <NUM> that gradually deforms (displaces) in response to a change in pressure.

However, the movable plate <NUM> is not limited to this configuration but, for example, may be made of relatively low-rigidity bimetal whose shape gradually changes with a temperature change. In this case, as an example, the movable plate <NUM> made of bimetal has an upwardly convex shape at low temperature as shown in <FIG> and gradually changes into a downwardly convex shape as the temperature rises, and the position of the upper end 25T of the actuation pin <NUM> is gradually lowered. Then, the sphere <NUM> rolls down the upper surface 41T without being held by the upper end 25T of the actuation pin <NUM> at predetermined temperature, so that the vibration generation unit 20f generates sound or vibration in response to a change in temperature which is an environmental state quantity.

One side of the movable plate <NUM> with relatively low rigidity may be pushed by the second portion 54b of the paddle <NUM> as included in the vibration generation unit 20e of the fifth example described above. This configuration can cause the vibration generation unit 20f to generate sound or vibration in response to a change in flow rate which is an environmental state quantity.

A measurement system 1a of a second embodiment will be described below with reference to <FIG>. The measurement system 1a of the second embodiment includes, in addition to the configuration of the measurement system <NUM> of the first embodiment described above, a detection unit <NUM> that detects an environmental state quantity such as temperature, pressure, and flow rate and a signal processing unit <NUM> that processes a signal relating to the environmental state quantity detected by the detection unit <NUM>. The transmission unit <NUM>, the signal processing unit <NUM>, and the detection unit <NUM> are driven when the voltage of the electric power supplied from the vibration-driven energy harvesting unit <NUM> becomes higher than the first voltage described above.

The detection unit <NUM> has a sensor <NUM> that detects temperature, pressure, flow rate, and the like which are environmental state quantities in the environment where the measurement system 1a is installed, and a detection circuit <NUM>. In a case where the detection unit <NUM> detects temperature, the sensor <NUM> includes a thermistor, a thermocouple, or the like; in a case where the detection unit <NUM> detects pressure, the sensor <NUM> includes a pressure sensor, a pressure transducer, or the like; and in a case where the detection unit <NUM> detects flow rate, the sensor <NUM> includes a vortex flow sensor, an electromagnetic flow meter, and the like.

As an example, the detection circuit <NUM> is a circuit including an amplifier element such as a transistor or a differential amplifier. The detection circuit <NUM> receives from a Sin terminal an analog signal output from the sensor <NUM>, performs processing such as amplification of the received signal, and outputs the processed analog signal as a first signal S1 from a Vout terminal. The electric power output from the power storage unit <NUM> of the vibration-driven energy harvesting unit <NUM> is supplied to the VCC terminal in the detection circuit <NUM>, and the GND terminal in the detection circuit <NUM> is connected to the ground.

As an example, the signal processing unit <NUM> is a semiconductor integrated circuit such as a microcontroller that includes an analog/digital converter and performs predetermined signal processing of a converted digital signal. An input terminal SI in the signal processing unit <NUM> is connected to the Vout terminal in the detection circuit <NUM> and the first signal S1 output from the Vout terminal in the detection circuit <NUM> is input into the input terminal SI in the signal processing unit <NUM>. The electric power output from the power storage unit <NUM> of the vibration-driven energy harvesting unit <NUM> is supplied to the VCC terminal in the signal processing unit <NUM> and the GND terminal in the signal processing unit <NUM> is connected to the ground.

The first signal S1 input into the input terminal SI in the signal processing unit <NUM> is converted (A/D-converted) from an analog signal to a digital signal in the signal processing unit <NUM>. Further, based on the first signal A/D-converted in the signal processing unit <NUM>, signal processing is performed to calculate numerical information on the environmental state quantity such as temperature, pressure, and flow rate detected by the sensor <NUM>. The numerical information extracted from the first signal S1 by signal processing is output as a digital second signal S2 from an output terminal SO in the signal processing unit <NUM>.

The signal processing unit <NUM> performs the signal processing described above according to a program stored in a ROM (not shown) or the like.

Incidentally, the signal processing also includes the processing of A/D-converting of the analog first signal S1 into the digital second signal S2. Thus, the second signal S2 may be a signal obtained by simply A/D-converting the first signal S1.

An input terminal SS in the communication circuit 31a is connected to the output terminal SO in the signal processing unit <NUM>, and the second signal S2 output from the output terminal SO in the signal processing unit <NUM> is input into the input terminal SS. The communication circuit 31a is basically the same as the communication circuit <NUM> in the first embodiment described above. However, the communication circuit 31a further has the function of modulating the second signal S2 input from the input terminal SS as a modulation signal suitable for wireless transmission from the antenna <NUM> to perform amplification and output the amplified modulation signal from the RF terminal to the antenna <NUM>. The modulation signal modulated based on the second signal is transmitted from the antenna <NUM> to the outside.

Incidentally, in a case where the numerical information on the environmental state quantity extracted from the first signal S1 by the signal processing is within a predetermined normal range, the signal processing unit <NUM> may transmit to the communication circuit 31a a signal for conveying unnecessariness of transmission instead of the second signal S2. The communication circuit 31a that has received the signal for conveying the unnecessariness of transmission does not perform transmission to the outside.

Also in the measurement system 1a of the second embodiment, in addition to the signal based on the information detected by the detection unit <NUM>, an identification signal unique to the measurement system 1a may be transmitted from the antenna <NUM> to the outside as in the measurement system <NUM> of the first embodiment described above.

Incidentally, the detection unit <NUM> is not limited to one that detects an environmental state quantity such as temperature, pressure, and flow rate but may be, for example, one that captures surrounding conditions of the measurement system 1a as an image or may be one that detects ambient sound. Accordingly, the signal processing unit <NUM> and the transmission unit <NUM> each may also process and transmit an image signal or an audio signal.

(<NUM>) The measurement system 1a of the second embodiment further includes, in addition to the measurement system <NUM> of the first embodiment described above, the detection unit <NUM> that is driven with the electric power generated by the vibration-driven energy harvesting unit <NUM> and performs predetermined detection, the transmission unit <NUM> transmitting information based on information obtained by performing, by the detection unit <NUM>, the predetermined detection. This configuration produces an effect that the detection unit <NUM> enables detecting and transmitting more accurate information in addition to the effect in the measurement system <NUM> of the first embodiment described above.

<FIG> is a diagram showing a schematic configuration of a diagnosis system <NUM> of one embodiment. As an example, the diagnosis system <NUM> is a system for diagnosing the operation state of a chemical plant <NUM> as an object to be diagnosed. In the diagnosis system <NUM>, in order to measure the environmental state quantity of each portion in the chemical plant <NUM>, the measurement system <NUM> of the first embodiment or the measurement system 1a of the second embodiment described above is arranged in the vicinity of each portion in the chemical plant <NUM>.

In the chemical plant <NUM>, a crude oil tank <NUM>, pipes (<NUM>, <NUM>, and the like), and the like are arranged in a complicated and dense manner, and a highly flammable raw material such as petroleum or high-pressure gas is used. Thus, it is difficult to arrange a measurement system that always uses electric power in the chemical plant <NUM>. However, the measurement systems <NUM> and 1a of the first embodiment and the second embodiment described above do not require wiring for supplying electric power or maintenance of a power supply such as a battery and thus are suitable for measuring complicated equipment such as the chemical plant <NUM>.

A measurement system 1b is installed in a location indicated by an arrow in <FIG> in a distillation column <NUM> of the chemical plant <NUM>. The measurement system 1b is the measurement system <NUM> described above and includes any one of the vibration generation units 20a to 20c that generates sound or vibration in response to a change in temperature as an environmental state quantity. The vibration generation units 20a to 20c in the measurement system 1b are arranged in contact with the side surface of the distillation column <NUM> or arranged such that at least a portion of the vibration generation units 20a to 20c is embedded within the distillation column <NUM>.

When the temperature of the side surface or inside of the distillation column <NUM> becomes predetermined temperature or higher, the vibration generation units 20a to 20c included in the measurement system 1b generate sound or vibration. Then, the vibration-driven energy harvesting unit <NUM> included in the measurement system 1b generates electric power using this sound or vibration, and a signal including the identification signal of the measurement system 1b is wirelessly transmitted from the transmission unit <NUM>.

A measurement system 1c is installed in a location indicated by an arrow in <FIG> in the pipe <NUM> of the chemical plant <NUM>. The measurement system 1c is the measurement system <NUM> described above and includes the vibration generation unit 20e that generates sound or vibration in response to a change in flow rate as an environmental state quantity. When the flow rate of liquid or gas flowing inside the pipe <NUM> becomes predetermined flow rate or higher, the vibration generation unit 20e included in the measurement system 1c generates sound or vibration. Then, the vibration-driven energy harvesting unit <NUM> included in the measurement system 1c generates electric power using this sound or vibration, and a signal including the identification signal of the measurement system 1c is wirelessly transmitted from the transmission unit <NUM>.

A measurement system 1d is installed in a location indicated by an arrow in <FIG> in the pipe <NUM> of the chemical plant <NUM>. The measurement system 1d is the measurement system <NUM> described above and includes the vibration generation unit 20d that generates sound or vibration in response to a change in pressure as an environmental state quantity. The vibration generation unit 20d is arranged such that at least a portion of the vibration generation unit 20d of the measurement system 1d is embedded in the pipe <NUM>.

When the pressure of liquid or gas inside the pipe <NUM> becomes predetermined pressure or higher, the vibration generation unit 20d included in the measurement system 1d generates sound or vibration. Then, the vibration-driven energy harvesting unit <NUM> included in the measurement system 1d generates electric power using this sound or vibration, and a signal including the identification signal of the measurement system 1d is wirelessly transmitted from the transmission unit <NUM>.

The signals transmitted wirelessly by the measurement systems 1b to 1d are received by a reception system <NUM>. The reception system <NUM> is supplied with electric power, for example, from a commercial power supply or the like, and is always kept in a state where the signals from the measurement systems 1b to 1d can be received. The reception system <NUM> can recognize from which of the measurement systems 1b to Id a signal is transmitted by recognizing the above-described identification signal included in the signal transmitted wirelessly by the measurement systems 1b to 1d. Consequently, the reception system <NUM> can diagnose which of the measurement systems 1b to 1d measures an environmental state quantity that has reached a level at which an alarm is issued.

Incidentally, as the measurement systems 1b to 1d, the measurement system <NUM> of the first embodiment including the above-described vibration generation unit 20f of the sixth example shown in <FIG> may be used. In this case, the vibration generation unit 20f may generate sound or vibration in response to a change in any one of temperature, pressure, and flow rate as described above.

Further, the measurement systems 1b to 1d are not limited to the measurement system <NUM> of the first embodiment described above, and the measurement system 1a of the second embodiment described above may also be used. In this case, the reception system <NUM> may also receive a signal transmitted from the measurement system 1a and based on the information detected by the detection unit <NUM> of the measurement system 1a.

In the one embodiment described above, the object to be diagnosed by the diagnosis system <NUM> is equipment constituting the chemical plant <NUM>, but the object to be diagnosed is not limited to this. The diagnosis system <NUM> may diagnose any object as long as the object is one for which an environmental state quantity such as temperature, pressure, and flow rate needs to be diagnosed. For example, air conditioner equipment in a large building, exhaust equipment in a factory, combustion equipment such as a boiler, and the like may be the objects to be diagnosed.

Incidentally, in the case of diagnosing equipment in which a highly flammable raw material is used, such as the chemical plant <NUM>, at least a portion of the vibration generation units <NUM>, 20a to 20f included in the measurement systems <NUM>, 1a may be manufactured of a material (metal such as copper, brass, and aluminum or ceramic or the like) which does not throw sparks due to impact at the time of generating sound or vibration. Alternatively, it may be manufactured of a metal material other than the above, and portions in contact with each other may be covered with a protective film such as resin. That is, the measurement systems 1b to 1d may satisfy the explosion-proof standard.

Incidentally, in the diagnosis system <NUM>, transmission from the measurement systems 1b to 1d to the reception system <NUM> may be performed via a line such as a telephone line or an internet line. That is, the signals transmitted from the measurement systems 1b to 1d may be received by a relay station first and then transmitted from the relay station to the reception system <NUM> via the line.

(<NUM>) The diagnosis system <NUM> of one embodiment includes the measurement systems 1b to 1d of the first embodiment or the second embodiment arranged in the vicinities of objects to be diagnosed (<NUM>, <NUM>, <NUM>) and a reception system that receives a signal transmitted from the measurement systems 1b to 1d and diagnoses the states of the objects to be diagnosed (<NUM>, <NUM>, <NUM>) based on the signal. Therefore, using the measurement systems 1b to 1d in which power consumption is significantly reduced eliminates the need for maintenance on the measurement systems 1b to 1d relating to wiring of a power line and a power supply such as battery replacement and can implement the diagnosis system <NUM> with low installation and maintenance costs.

Although various embodiments and modifications have been described above, the present invention is not limited to these contents. Additionally, each embodiment and modification may be applied individually or may be used in combination. The other aspects conceivable within the scope of the technical idea of the present invention are also included within the scope of the present invention.

The disclosure contents of the following priority basic application are incorporated herein as citations.

Claim 1:
A measurement system (<NUM>, 1a to 1d) comprising:
a vibration generation unit (<NUM>, 20a to 20f) that is configured to generate sound or vibration in response to a change in environmental state quantity;
a vibration-driven energy harvesting unit (<NUM>) that is configured to generate electric power using the sound or vibration generated by the vibration generation unit (<NUM>, 20a to 20f); and
a transmission unit (<NUM>) that is driven with the electric power generated by the vibration-driven energy harvesting unit (<NUM>) and configured to transmit predetermined information,
the measurement system being characterized in that the environmental state quantity is flow rate; the vibration generation unit (20e) further includes a displacement unit (<NUM>), a position of at least a portion of the displacement unit (<NUM>) changing in response to a change in flow rate; and
the vibration generation unit (<NUM>, 20a to 20f) includes a deformation member (<NUM>, <NUM>, <NUM>) whose shape suddenly changes from a first shape to a second shape in response to a change in flow rate according to a position of the displacement unit (<NUM>).